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Carnazzo MC, Scholin C, Shweta FNU, Calvin AD. Lyme disease presenting as complete heart block in a young man: Case report and review of pathogenesis. IDCases 2023; 32:e01799. [PMID: 37234726 PMCID: PMC10205533 DOI: 10.1016/j.idcr.2023.e01799] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2023] [Revised: 05/11/2023] [Accepted: 05/11/2023] [Indexed: 05/28/2023] Open
Abstract
Lyme carditis is a serious complication of Lyme disease, the most common vector-borne infection in both the United States and Northern Europe. It is a rare manifestation of Lyme disease that primarily affects young adults with a marked 3:1 male-to-female predominance. The presentation of Lyme carditis is heterogenous and often non-specific, although the most common clinical manifestation is AV block, which can be acute in onset and can rapidly progress to complete heart block. We discuss the case of a young adult male with complete heart block as a complication of Lyme infection, presenting with two episodes of syncope without prodromal symptoms months after tick bites. There are several pathogen, host and environmental factors that can play an important role in the epidemiology and pathogenesis of this serious condition that is reversible if treated in a timely manner. It is important for clinicians to be familiar with the presentation and treatment of this infection that is now being observed in a wider geographic distribution so as to avoid serious long-term complications and unnecessary permanent pacemaking implantation.
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Affiliation(s)
- Maria Chiara Carnazzo
- Post-graduate School of Emergency Medicine, Faculty of Medicine and Surgery, University of Modena and Reggio Emilia, Modena, MO 41125, Italy
| | - Celine Scholin
- Medical College of Wisconsin - Central Wisconsin, Wausau, WI 54401, United States
| | - FNU Shweta
- Department of Infectious Disease, Mayo Clinic Health System, Eau Claire, WI 54703, United States
| | - Andrew D. Calvin
- Department of Cardiovascular Medicine, Mayo Clinic Health System, Eau Claire, WI 54703, United States
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Yang N, Han X, Zhang J, Zhang S, Sun J. What can we find in QRS in patients with ST-segment-elevation myocardial infarction? J Electrocardiol 2022. [DOI: 10.1016/j.jelectrocard.2022.09.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
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3
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Embryology and Etiology. CONGENIT HEART DIS 2022. [DOI: 10.1016/b978-1-56053-368-9.00002-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Han X, Chen Z, Wang Y, Zhang J, Zhang Y, Su Q, Pan Z, Sun J, Wang Y. Prognostic significance of QRS distortion and frontal QRS-T angle in patients with ST-elevation myocardial infarction. Int J Cardiol 2021; 345:1-6. [PMID: 34715207 DOI: 10.1016/j.ijcard.2021.10.139] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Revised: 09/27/2021] [Accepted: 10/22/2021] [Indexed: 01/17/2023]
Abstract
BACKGROUND QRS distortion (G3I) and frontal QRS-T angle (fQRS-T angle) are both electrocardiographic (ECG) signs of ongoing ischemia and depolarization-repolarization heterogeneity, which always occur in patients with ST-segment elevation acute myocardial infarction (STEMI). METHODS We retrospectively collected 592 STEMI patients who underwent coronary angiography and follow-up for 42 months. 1. We divided the patients into two groups according to whether they had G3I on admission, compared the differences in examination data and endpoint events between these two groups. 2. Group patients according to whether the endpoint events happened in hospital, at 12 and 42 months, compare whether there is a difference in fQRS-T angle at the same time point, and find out the predictive cutoff value of all-cause death. 3. Combined G3I and fQRS-T angle together to enhance the predictive value. RESULTS G3I and fQRS-T angle are both independent risk factors for all-cause death in STEMI patients within 12 months (G3I P = 0.014, fQRS-T angle P < 0.001) and within 42 months (P < 0.001). The cutoff values of fQRS-T angle for predicting all-cause death are 66.5° at 12 months and 90.5° at 42 months. When G3I and fQRS-T angle are combined used to predict the mortality, the specificity is significantly improved, but the sensitivity decreased. CONCLUSIONS G3I and fQRS-T angles are valuable in the prognostic assessment of STEMI patients, especially when combined. These findings help clinicians to identify high-risk patients early for more aggressive treatment.
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Affiliation(s)
- Xiaorong Han
- Department of Cardiovascular Center, Jilin University First Hospital, China.
| | - Zhongbo Chen
- Department of Cardiovascular Center, Jilin University First Hospital, China.
| | - Yinghui Wang
- Department of Cardiovascular Center, Jilin University First Hospital, China.
| | - Jin Zhang
- Department of Cardiovascular Center, Jilin University First Hospital, China.
| | - Ying Zhang
- Department of Cardiovascular Center, Jilin University First Hospital, China.
| | - Qiang Su
- Department of Cardiovascular Center, Jilin University First Hospital, China.
| | - Zhenghu Pan
- Department of Cardiovascular Center, Jilin University First Hospital, China.
| | - Jian Sun
- Department of Cardiovascular Center, Jilin University First Hospital, China.
| | - Yonggang Wang
- Department of Cardiovascular Center, Jilin University First Hospital, China.
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5
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Disease Modeling and Disease Gene Discovery in Cardiomyopathies: A Molecular Study of Induced Pluripotent Stem Cell Generated Cardiomyocytes. Int J Mol Sci 2021; 22:ijms22073311. [PMID: 33805011 PMCID: PMC8037452 DOI: 10.3390/ijms22073311] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2021] [Revised: 03/19/2021] [Accepted: 03/22/2021] [Indexed: 01/04/2023] Open
Abstract
The in vitro modeling of cardiac development and cardiomyopathies in human induced pluripotent stem cell (iPSC)-derived cardiomyocytes (CMs) provides opportunities to aid the discovery of genetic, molecular, and developmental changes that are causal to, or influence, cardiomyopathies and related diseases. To better understand the functional and disease modeling potential of iPSC-differentiated CMs and to provide a proof of principle for large, epidemiological-scale disease gene discovery approaches into cardiomyopathies, well-characterized CMs, generated from validated iPSCs of 12 individuals who belong to four sibships, and one of whom reported a major adverse cardiac event (MACE), were analyzed by genome-wide mRNA sequencing. The generated CMs expressed CM-specific genes and were highly concordant in their total expressed transcriptome across the 12 samples (correlation coefficient at 95% CI =0.92 ± 0.02). The functional annotation and enrichment analysis of the 2116 genes that were significantly upregulated in CMs suggest that generated CMs have a transcriptomic and functional profile of immature atrial-like CMs; however, the CMs-upregulated transcriptome also showed high overlap and significant enrichment in primary cardiomyocyte (p-value = 4.36 × 10−9), primary heart tissue (p-value = 1.37 × 10−41) and cardiomyopathy (p-value = 1.13 × 10−21) associated gene sets. Modeling the effect of MACE in the generated CMs-upregulated transcriptome identified gene expression phenotypes consistent with the predisposition of the MACE-affected sibship to arrhythmia, prothrombotic, and atherosclerosis risk.
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Mohan RA, Bosada FM, van Weerd JH, van Duijvenboden K, Wang J, Mommersteeg MTM, Hooijkaas IB, Wakker V, de Gier-de Vries C, Coronel R, Boink GJJ, Bakkers J, Barnett P, Boukens BJ, Christoffels VM. T-box transcription factor 3 governs a transcriptional program for the function of the mouse atrioventricular conduction system. Proc Natl Acad Sci U S A 2020; 117:18617-18626. [PMID: 32675240 PMCID: PMC7414162 DOI: 10.1073/pnas.1919379117] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
Genome-wide association studies have identified noncoding variants near TBX3 that are associated with PR interval and QRS duration, suggesting that subtle changes in TBX3 expression affect atrioventricular conduction system function. To explore whether and to what extent the atrioventricular conduction system is affected by Tbx3 dose reduction, we first characterized electrophysiological properties and morphology of heterozygous Tbx3 mutant (Tbx3+/-) mouse hearts. We found PR interval shortening and prolonged QRS duration, as well as atrioventricular bundle hypoplasia after birth in heterozygous mice. The atrioventricular node size was unaffected. Transcriptomic analysis of atrioventricular nodes isolated by laser capture microdissection revealed hundreds of deregulated genes in Tbx3+/- mutants. Notably, Tbx3+/- atrioventricular nodes showed increased expression of working myocardial gene programs (mitochondrial and metabolic processes, muscle contractility) and reduced expression of pacemaker gene programs (neuronal, Wnt signaling, calcium/ion channel activity). By integrating chromatin accessibility profiles (ATAC sequencing) of atrioventricular tissue and other epigenetic data, we identified Tbx3-dependent atrioventricular regulatory DNA elements (REs) on a genome-wide scale. We used transgenic reporter assays to determine the functionality of candidate REs near Ryr2, an up-regulated chamber-enriched gene, and in Cacna1g, a down-regulated conduction system-specific gene. Using genome editing to delete candidate REs, we showed that a strong intronic bipartite RE selectively governs Cacna1g expression in the conduction system in vivo. Our data provide insights into the multifactorial Tbx3-dependent transcriptional network that regulates the structure and function of the cardiac conduction system, which may underlie the differences in PR duration and QRS interval between individuals carrying variants in the TBX3 locus.
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Affiliation(s)
- Rajiv A Mohan
- Department of Medical Biology, Amsterdam University Medical Centers, University of Amsterdam, 1105 AZ Amsterdam, The Netherlands
- Department of Clinical and Experimental Cardiology, Amsterdam University Medical Centers, University of Amsterdam, 1105 AZ Amsterdam, The Netherlands
| | - Fernanda M Bosada
- Department of Medical Biology, Amsterdam University Medical Centers, University of Amsterdam, 1105 AZ Amsterdam, The Netherlands
| | - Jan H van Weerd
- Department of Medical Biology, Amsterdam University Medical Centers, University of Amsterdam, 1105 AZ Amsterdam, The Netherlands
| | - Karel van Duijvenboden
- Department of Medical Biology, Amsterdam University Medical Centers, University of Amsterdam, 1105 AZ Amsterdam, The Netherlands
| | - Jianan Wang
- Department of Clinical and Experimental Cardiology, Amsterdam University Medical Centers, University of Amsterdam, 1105 AZ Amsterdam, The Netherlands
| | - Mathilda T M Mommersteeg
- Burdon Sanderson Cardiac Science Centre, Department of Physiology, Anatomy & Genetics, University of Oxford, Oxford OX1 3PT, United Kingdom
| | - Ingeborg B Hooijkaas
- Department of Medical Biology, Amsterdam University Medical Centers, University of Amsterdam, 1105 AZ Amsterdam, The Netherlands
| | - Vincent Wakker
- Department of Medical Biology, Amsterdam University Medical Centers, University of Amsterdam, 1105 AZ Amsterdam, The Netherlands
| | - Corrie de Gier-de Vries
- Department of Medical Biology, Amsterdam University Medical Centers, University of Amsterdam, 1105 AZ Amsterdam, The Netherlands
| | - Ruben Coronel
- Department of Clinical and Experimental Cardiology, Amsterdam University Medical Centers, University of Amsterdam, 1105 AZ Amsterdam, The Netherlands
| | - Gerard J J Boink
- Department of Medical Biology, Amsterdam University Medical Centers, University of Amsterdam, 1105 AZ Amsterdam, The Netherlands
- Department of Clinical and Experimental Cardiology, Amsterdam University Medical Centers, University of Amsterdam, 1105 AZ Amsterdam, The Netherlands
| | - Jeroen Bakkers
- Hubrecht Institute and University Medical Center Utrecht, 3584 CT Utrecht, the Netherlands
| | - Phil Barnett
- Department of Medical Biology, Amsterdam University Medical Centers, University of Amsterdam, 1105 AZ Amsterdam, The Netherlands
| | - Bas J Boukens
- Department of Medical Biology, Amsterdam University Medical Centers, University of Amsterdam, 1105 AZ Amsterdam, The Netherlands
- Department of Clinical and Experimental Cardiology, Amsterdam University Medical Centers, University of Amsterdam, 1105 AZ Amsterdam, The Netherlands
| | - Vincent M Christoffels
- Department of Medical Biology, Amsterdam University Medical Centers, University of Amsterdam, 1105 AZ Amsterdam, The Netherlands;
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Prasitlumkum N, Sirinvaravong N, Limpruttidham N, Rattanawong P, Tom E, Kanitsoraphan C, Chongsathidkiet P, Boondarikpornpant T. Terminal QRS Distortion in ST Elevation Myocardial Infarction as a Prediction of Mortality: Systematic Review and Meta-Analysis. ACTA CARDIOLOGICA SINICA 2019; 35:445-458. [PMID: 31571793 DOI: 10.6515/acs.201909_35(5).20180909a] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Background Terminal QRS distortion reflects advanced stage and large myocardial infarction predisposing the heart to adverse outcomes. Recent studies suggest that terminal QRS distortion is associated with morbidity and mortality in ST elevation myocardial infarction (STEMI). However, a systematic review and meta-analysis of the literature have not been done. Objective We assessed the association between terminal QRS distortion in patients with STEMI and mortality by a systematic review of the literature and a meta-analysis. Methods We comprehensively searched the databases of MEDLINE and EMBASE from inception to September 2017. Included studies were published prospective or retrospective cohort studies that compared all-cause mortality in subjects with STEMI with QRS distortion versus those without QRS distortion. Data from each study were combined using the random-effects, generic inverse variance method of DerSimonian and Laird to calculate risk ratios and 95% confidence intervals. Results Fifteen studies from January 1993 to May 2015 were included in this meta-analysis involving 7,479 subjects with STEMI (2,906 QRS distortion and 4,573 non-QRS distortion). QRS distortion was associated with increased mortality (pooled risk ratio = 1.81, 95% confidence interval: 1.37-2.40, p < 0.000, I2 = 41.6%). Considering the introduction of clopidogrel in 2004, we performed subgroup analyses before and after 2004, and the associated with higher mortality was still present (before 2004, RR 1.75, 95% CI 1.08-2.82, p = 0.022, I2 = 66.1%; after 2004, RR 1.96, 95% CI 1.44-2.65, p < 0.001, I2 = 0%). Conclusions Terminal QRS distortion increased all-cause mortality by 81%. Our study suggests that terminal QRS distortion is an important tool to assess the risk in patients with STEMI.
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Affiliation(s)
| | | | | | - Pattara Rattanawong
- University of Hawaii Internal Medicine Residency Program, Honolulu, HI.,Faculty of Medicine Ramathibodi Hospital, Mahidol University, Bangkok, Thailand
| | - Elysse Tom
- University of Hawaii Internal Medicine Residency Program, Honolulu, HI
| | | | - Pakawat Chongsathidkiet
- Faculty of Medicine Ramathibodi Hospital, Mahidol University, Bangkok, Thailand.,Department of Pathology, Duke University Medical Center, Durham, North Carolina, USA
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Abstract
The rate and rhythm of heart muscle contractions are coordinated by the cardiac conduction system (CCS), a generic term for a collection of different specialized muscular tissues within the heart. The CCS components initiate the electrical impulse at the sinoatrial node, propagate it from atria to ventricles via the atrioventricular node and bundle branches, and distribute it to the ventricular muscle mass via the Purkinje fibre network. The CCS thereby controls the rate and rhythm of alternating contractions of the atria and ventricles. CCS function is well conserved across vertebrates from fish to mammals, although particular specialized aspects of CCS function are found only in endotherms (mammals and birds). The development and homeostasis of the CCS involves transcriptional and regulatory networks that act in an embryonic-stage-dependent, tissue-dependent, and dose-dependent manner. This Review describes emerging data from animal studies, stem cell models, and genome-wide association studies that have provided novel insights into the transcriptional networks underlying CCS formation and function. How these insights can be applied to develop disease models and therapies is also discussed.
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9
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Sharma AK, Almaddah N, Chaudhry K, Ganatra S, Chaudhry GM, Silver J. Without Further Delay: Lyme Carditis. Am J Med 2018; 131:384-386. [PMID: 29157649 DOI: 10.1016/j.amjmed.2017.11.004] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/08/2017] [Revised: 11/03/2017] [Accepted: 11/03/2017] [Indexed: 11/16/2022]
Affiliation(s)
- Ajay K Sharma
- Department of Cardiovascular Medicine, Lahey Hospital Medical Center, Burlington, Mass.
| | - Nureddin Almaddah
- Department of Cardiovascular Medicine, Lahey Hospital Medical Center, Burlington, Mass
| | - Kashif Chaudhry
- Department of Cardiovascular Medicine, Lahey Hospital Medical Center, Burlington, Mass
| | - Sarju Ganatra
- Department of Cardiovascular Medicine, Lahey Hospital Medical Center, Burlington, Mass
| | - Ghulam M Chaudhry
- Department of Cardiovascular Medicine, Lahey Hospital Medical Center, Burlington, Mass
| | - Jonathan Silver
- Department of Cardiovascular Medicine, Lahey Hospital Medical Center, Burlington, Mass
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10
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Weber M, Scherf N, Meyer AM, Panáková D, Kohl P, Huisken J. Cell-accurate optical mapping across the entire developing heart. eLife 2017; 6. [PMID: 29286002 PMCID: PMC5747520 DOI: 10.7554/elife.28307] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2017] [Accepted: 12/02/2017] [Indexed: 11/14/2022] Open
Abstract
Organogenesis depends on orchestrated interactions between individual cells and morphogenetically relevant cues at the tissue level. This is true for the heart, whose function critically relies on well-ordered communication between neighboring cells, which is established and fine-tuned during embryonic development. For an integrated understanding of the development of structure and function, we need to move from isolated snap-shot observations of either microscopic or macroscopic parameters to simultaneous and, ideally continuous, cell-to-organ scale imaging. We introduce cell-accurate three-dimensional Ca2+-mapping of all cells in the entire electro-mechanically uncoupled heart during the looping stage of live embryonic zebrafish, using high-speed light sheet microscopy and tailored image processing and analysis. We show how myocardial region-specific heterogeneity in cell function emerges during early development and how structural patterning goes hand-in-hand with functional maturation of the entire heart. Our method opens the way to systematic, scale-bridging, in vivo studies of vertebrate organogenesis by cell-accurate structure-function mapping across entire organs. The heart has a built-in pacemaker that sets the rhythm of the heartbeat. Pacemaker cells produce electrical signals that spread across the heart in a coordinated wave. As each cell receives its signal, ion channels open in its membrane. Calcium ions rush in from the spaces around the cells, triggering the release of more calcium ions from internal stores. The rise in calcium ion levels causes the heart muscle to contract. Standard techniques for studying how the activation process spreads across the heart typically involve removing the organ from the animal. One reason for this is that no microscopy technique had been able to provide the detail needed to observe the activity of individual cells across the whole heart during its activation cycle. Zebrafish embryos have a simple heart with two chambers that can be visually explored because the embryos are transparent. Their hearts are activated in a pattern that has been maintained throughout evolution with principal similarities in many different species. These properties make fish embryos well suited for the non-invasive examination of the heart. Weber, Scherf et al. have studied genetically engineered zebrafish embryos whose heart muscle cells contained a calcium-sensitive fluorophore, using a technique called light sheet microscopy. This method illuminates the heart with a thin sheet of laser light, which causes the fluorescent dye to glow in a way that indicates changes in the concentration of calcium ions in the cells. A fast and sensitive camera detects these signals and stacks of movies are recorded and synchronized, allowing cardiac activation to be mapped in three dimensions as it spreads across the heart. Applying this new technique revealed that different parts of the heart conduct activation signals at different speeds. These speeds finely match the anatomical features of the heart, yielding planar progression of the activation signal over the increasingly complex shape of the developing heart. Weber, Scherf et al. also showed that the heart only requires a handful of pacemaker cells to reliably set the heart’s rhythm. Future modifications to the technique of Weber, Scherf et al. could help us investigate how the heart works in even finer detail. For example, it might reveal how electrical activity, calcium handling, and contraction influence one another, and how they individually and collectively respond to drug treatments. This will help us understand how the normal heart rhythm develops, how it can be modified, and how the heart adapts to changes in its environment, including damage during cardiac disease.
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Affiliation(s)
- Michael Weber
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany.,Harvard Medical School, Boston, United States
| | - Nico Scherf
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany.,Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany
| | - Alexander M Meyer
- Max-Delbrück-Center for Molecular Medicine in the Helmholtz Association, Berlin, Germany
| | - Daniela Panáková
- Max-Delbrück-Center for Molecular Medicine in the Helmholtz Association, Berlin, Germany.,DZHK (German Centre for Cardiovascular Research), partner site Berlin, Germany
| | - Peter Kohl
- Institute for Experimental Cardiovascular Medicine, University Heart Centre Freiburg - Bad Krozingen, Faculty of Medicine, Albert-Ludwigs University, Freiburg, Germany
| | - Jan Huisken
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany.,Morgridge Institute for Research, Madison, United States
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11
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Greulich F, Trowe MO, Leffler A, Stoetzer C, Farin HF, Kispert A. Misexpression of Tbx18 in cardiac chambers of fetal mice interferes with chamber-specific developmental programs but does not induce a pacemaker-like gene signature. J Mol Cell Cardiol 2016; 97:140-9. [PMID: 27180262 DOI: 10.1016/j.yjmcc.2016.05.004] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/09/2016] [Revised: 04/13/2016] [Accepted: 05/09/2016] [Indexed: 11/20/2022]
Abstract
Initiation of cardiac excitation depends on a specialized group of cardiomyocytes at the venous pole of the heart, the sinoatrial node (SAN). The T-box transcription factor gene Tbx18 is expressed in the SAN myocardium and is required for formation of a large portion of the pacemaker. Previous studies suggested that Tbx18 is also sufficient to reprogram ventricular cardiomyocytes into SAN cells in rat, guinea-pig and pig hearts. To evaluate the consequences of misexpression of Tbx18 for imposing a nodal phenotype onto chamber myocardial cells in fetal mice, we used two independent conditional approaches with chamber-specific cre driver lines and an Hprt(Tbx18) misexpression allele. Myh6-Cre/+;Hprt(Tbx18/y) mice developed dilated atria with thickened walls, reduced right ventricles and septal defects that resulted in reduced embryonic and post-natal survival. Tagln-Cre/+;Hprt(Tbx18/y) mice exhibited slightly smaller hearts with rounded trabeculae that supported normal embryonic survival. Molecular analyses showed that the SAN gap junction and ion channel profile was not ectopically induced in chamber myocardium but the working myocardial gene program was partially inhibited in atria and ventricles of both misexpression models. Left atrial expression of Pitx2 was strongly repressed in Myh6-Cre/+;Hprt(Tbx18/y) embryos. We conclude that exclusion of Tbx18 expression from the developing atria and (right) ventricle is important to achieve normal cardiac left-right patterning and myocardial differentiation, and that Tbx18 is not sufficient to induce full SAN differentiation of chamber cardiomyocytes in fetal mice.
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Affiliation(s)
- Franziska Greulich
- Institut für Molekularbiologie, OE5250, Medizinische Hochschule Hannover, Carl-Neuberg-Str.1, D-30625 Hannover, Germany
| | - Mark-Oliver Trowe
- Institut für Molekularbiologie, OE5250, Medizinische Hochschule Hannover, Carl-Neuberg-Str.1, D-30625 Hannover, Germany
| | - Andreas Leffler
- Klinik für Anästhesiologie und Intensivmedizin, OE8050, Medizinische Hochschule Hannover, Carl-Neuberg-Str.1, D-30625 Hannover, Germany
| | - Carsten Stoetzer
- Klinik für Anästhesiologie und Intensivmedizin, OE8050, Medizinische Hochschule Hannover, Carl-Neuberg-Str.1, D-30625 Hannover, Germany
| | - Henner F Farin
- Institut für Molekularbiologie, OE5250, Medizinische Hochschule Hannover, Carl-Neuberg-Str.1, D-30625 Hannover, Germany
| | - Andreas Kispert
- Institut für Molekularbiologie, OE5250, Medizinische Hochschule Hannover, Carl-Neuberg-Str.1, D-30625 Hannover, Germany.
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12
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The "Dead-End Tract" and Its Role in Arrhythmogenesis. J Cardiovasc Dev Dis 2016; 3:jcdd3020011. [PMID: 29367562 PMCID: PMC5715688 DOI: 10.3390/jcdd3020011] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2015] [Revised: 02/02/2016] [Accepted: 03/17/2016] [Indexed: 11/17/2022] Open
Abstract
Idiopathic outflow tract ventricular arrhythmias (VAs) represent a significant proportion of all VAs. The mechanism is thought to be catecholamine-mediated delayed after depolarizations and triggered activity, although other etiologies should be considered. In the adult cardiac conduction system it has been demonstrated that sometimes an embryonic branch, the so-called "dead-end tract", persists beyond the bifurcation of the right and left bundle branch (LBB). Several findings suggest an involvement of this tract in idiopathic VAs (IVAs). The aim of this review is to summarize our current knowledge and the possible clinical significance of this tract.
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13
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Niu T, Fu P, Jia C, Dong Y, Liang C, Cao Q, Yang Z, Fu R, Zhang X, Sun Z. The delayed activation wave in non-ST-elevation myocardial infarction. Int J Cardiol 2013; 162:107-11. [PMID: 21663984 DOI: 10.1016/j.ijcard.2011.05.063] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/13/2010] [Revised: 03/01/2011] [Accepted: 05/13/2011] [Indexed: 11/17/2022]
Abstract
BACKGROUND Little is known about the relationship between the electrocardiographic characteristics and the infarct related artery (IRA) in non-ST-elevation myocardial infarction (NSTEMI). We found a curious phenomenon in electrocardiograms of patients with acute occlusion of left circumflex artery in NSTEM: A notch or deflection was often present in the terminal QRS complex in leads II,III and aVF or I,aVL . The objective of this study was to determine whether the previously unreported ECG phenomenon that we have found in NSTEMI could identify the culprit artery in non-ST-elevation myocardial infarction. METHODS AND RESULTS Our study included 218 NSTEMI patients who presented to our institution and underwent coronary angiography within 24 hours of admission. For convenience, 'N' wave was defined as a notch or deflection in the terminal QRS complex of the surface ECG. The duration of QRS with N wave before PCI was more prolonged than the duration of QRS without N wave (121 ± 12 ms vs 106 ± 11 ms, P<0.01). In the LCX group, 66(77%) patients had N wave in leads II, III and aVF, whereas only 5(6%) patients in the LAD group and 9(18%) patients in the RCA group had such ECG feature (P<0.001). A greater proportion of patients in the LCX group also had N waves in leads I and aVL (P<0.001). N wave in leads II, III and aVF was associated with 77% sensitivity and 89% specificity, respectively. N wave in leads I and aVL was associated with 64% sensitivity and 96% specificity, respectively. CONCLUSION The abnormal waveform in terminal QRS complex in NSTEMI ,which is described above, is the delayed activation wave of left ventricular basal region which the left circumflex artery supplies. It is associated with a higher specificity and higher sensitivity for culprit LCX in non-ST-elevation myocardial infarction. The delayed activation wave is a new pattern of ischemia in ECG.
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Affiliation(s)
- Tiesheng Niu
- Department of Cardiology, Shengjing Hospital of China Medical University, Shenyang 110004, China.
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14
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Bakker ML, Boink GJ, Boukens BJ, Verkerk AO, van den Boogaard M, den Haan AD, Hoogaars WM, Buermans HP, de Bakker JM, Seppen J, Tan HL, Moorman AF, 't Hoen PA, Christoffels VM. T-box transcription factor TBX3 reprogrammes mature cardiac myocytes into pacemaker-like cells. Cardiovasc Res 2012; 94:439-49. [DOI: 10.1093/cvr/cvs120] [Citation(s) in RCA: 114] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
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Nimura A, Sakamoto N, Nakagawa N, Ota H, Tanabe Y, Takeuchi T, Natori S, Sato N, Hasebe N, Kawamura Y. Site of Transmural Late Gadolinium Enhancement on the Cardiac MRI Coincides With the ECG Leads Exhibiting Terminal QRS Distortion in Patients With ST-Elevation Myocardial Infarctions. Int Heart J 2012; 53:270-5. [DOI: 10.1536/ihj.53.270] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Affiliation(s)
- Asami Nimura
- Division of Cardiology, Nephrology, Pulmonology and Neurology, Department of Internal Medicine, Asahikawa Medical University
| | - Naka Sakamoto
- Division of Cardiology, Nephrology, Pulmonology and Neurology, Department of Internal Medicine, Asahikawa Medical University
| | - Naoki Nakagawa
- Division of Cardiology, Nephrology, Pulmonology and Neurology, Department of Internal Medicine, Asahikawa Medical University
| | - Hisanobu Ota
- Division of Cardiology, Nephrology, Pulmonology and Neurology, Department of Internal Medicine, Asahikawa Medical University
| | - Yasuko Tanabe
- Division of Cardiology, Nephrology, Pulmonology and Neurology, Department of Internal Medicine, Asahikawa Medical University
| | - Toshiharu Takeuchi
- Division of Cardiology, Nephrology, Pulmonology and Neurology, Department of Internal Medicine, Asahikawa Medical University
| | | | - Nobuyuki Sato
- Division of Cardiology, Nephrology, Pulmonology and Neurology, Department of Internal Medicine, Asahikawa Medical University
| | - Naoyuki Hasebe
- Division of Cardiology, Nephrology, Pulmonology and Neurology, Department of Internal Medicine, Asahikawa Medical University
| | - Yuichiro Kawamura
- Division of Cardiology, Nephrology, Pulmonology and Neurology, Department of Internal Medicine, Asahikawa Medical University
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Bakker ML, Moorman AF, Christoffels VM. The Atrioventricular Node: Origin, Development, and Genetic Program. Trends Cardiovasc Med 2010; 20:164-71. [DOI: 10.1016/j.tcm.2011.02.001] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/02/2010] [Accepted: 10/07/2010] [Indexed: 12/15/2022]
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The Cardiac Pacemaker and Conduction System Develops From Embryonic Myocardium that Retains Its Primitive Phenotype. J Cardiovasc Pharmacol 2010; 56:6-15. [DOI: 10.1097/fjc.0b013e3181e775d3] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
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Lieberman M, Paes de Carvalho A. The Electrophysiological Organization of the Embryonic Chick Heart. ACTA ACUST UNITED AC 2010; 49:351-63. [PMID: 19873567 PMCID: PMC2195476 DOI: 10.1085/jgp.49.2.351] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Both intracellular and surface electrodes were employed to record electrical activity from embryonic chick hearts between the ages of 3 and 20 days. Cells from the sinus venosus, sinoatrial (SA) valves, atrium, atrioventricular (AV) ring, and ventricle were localized and characterized on the basis of shape, amplitude, rise time, and duration of transmembrane potentials. The differences in transmembrane potentials from these various regions provided the basis for a hypothesis concerned with the distribution of pacemaker potentiality and one related to the origin of the His-Purkinje system. Action potentials recorded along the entire embryonic AV ring were comparable to those of the adult rabbit AV nodal cells in both configuration and sequence of activation and were thus categorized into three functional regions (AN, N, NH). Histological sections of 7 and 14 day hearts demonstrated muscular continuity between the right atrium and ventricle across the muscular AV valve.
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Affiliation(s)
- M Lieberman
- Department of Physiology, State University of New York, Downstate Medical Center, Brooklyn, New York, and Instituto de Biofisica, Universidade do Brasil, Rio de Janeiro, Brasil
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Nakamura N, Gohda M, Satani O, Tomobuchi Y, Ueno Y, Tanimoto T, Kitabata H, Takarada S, Kubo T, Mizukoshi M, Hirata K, Tanaka A, Imanishi T, Akasaka T. Myocardial salvage for ST-elevation myocardial infarction with terminal QRS distortion and restoration of brisk epicardial coronary flow. Heart Vessels 2009; 24:96-102. [PMID: 19337792 DOI: 10.1007/s00380-008-1092-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/22/2008] [Accepted: 07/10/2008] [Indexed: 11/30/2022]
Abstract
Recently, it has been reported that large infarcts associated with terminal QRS distortion (QRSDIS) on the admission electrocardiograms of patients with ST-elevation myocardial infarctions (STEMIs) may be caused by a failure to achieve thrombolysis in myocardial infarction (TIMI) grade 3 flow after primary percutaneous coronary intervention (PCI). However, the relationship between QRSDIS and final infarct size when TIMI grade 3 flow could be achieved by primary PCI is still unclear. Sixty-two consecutive patients with first anterior STEMI and who achieved TIMI grade 3 flow by primary PCI were classified into two groups according to the presence (Group A, n = 18) or absence (Group B, n = 44) of QRSDIS. Two weeks after the onset of acute myocardial infarction, Group A had a larger left ventricular (LV) end-systolic volume index (LVESVI) and a lower LV ejection fraction (LVEF) than Group B (LVESVI: 38 +/- 13 vs 31 +/- 12 ml/m(2), P = 0.025: LVEF: 42% +/- 10% vs 51% +/- 10%, P = 0.004). Through multivariate analysis, independent predictors of poor LV systolic function (LVEF < 40%) were determined to be the presence of QRSDIS (odds ratio 21.04, P = 0.021) and proximal left anterior descending artery occlusion (odds ratio 16.15, P = 0.033). Myocardial damage could not be reduced in patients experiencing STEMI with QRSDIS, even when TIMI grade 3 flow could be achieved by primary PCI, as much as in patients experiencing STEMI without QRSDIS.
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Affiliation(s)
- Nobuo Nakamura
- Department of Cardiovascular Medicine, Wakayama Medical University, Kimiidera, Wakayama, Japan
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Celik T, Yuksel UC, Iyisoy A, Kilic S, Kardesoglu E, Bugan B, Isik E. The impact of preinfarction angina on electrocardiographic ischemia grades in patients with acute myocardial infarction treated with primary percutaneous coronary intervention. Ann Noninvasive Electrocardiol 2008; 13:278-86. [PMID: 18713329 DOI: 10.1111/j.1542-474x.2008.00232.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
OBJECTIVE Grade 3 ischemia (G3I) is defined as ST elevation with distortion of the terminal portion of the QRS (emergence of the J point > 50% of the R wave in leads with qR configuration, or disappearance of the S wave in leads with an Rs configuration). Patients with G3I on the presenting electrocardiogram (ECG) had worse prognosis than the patients with lesser (grade 2-G2I) ischemia. The aim of this study is to examine the effects of preinfarct angina (PIA) on electrocardiographic ischemia grades. METHODS One hundred forty-eight consecutive patients with ST-segment myocardial infarction (STEMI) were included in this study. All patients underwent primary percutaneous coronary intervention. The admission ECGs was analyzed retrospectively for electrocardiographic ischemia grades and compared with the presence of PIA. RESULTS Study population consisted of 110 patients with G2I (88 men, mean age = 63 +/- 6 years) and 38 patients with G3I (32 men, mean age = 61 +/- 8 years). Baseline characteristics of the groups were the same except for patients with G3I had significantly longer pain to balloon time and higher admission creatine kinase MB isoenzyme (CK-MB) levels. Tissue myocardial perfusion grade (TMPG) was better in patients with G2I. While 18 patients (47%) with G3I had PIA, 81 patients (70%) with G2I had PIA (P = 0.005). Although pain to balloon time and admission CK-MB were independent predictor of worse electrocardiographic ischemia grade (OR 1.69, 95% CI 1.09-2.62; P = 0.01; OR 1.01, 1.00-1.02, P = 0.04), PIA and left ventricular ejection time (LVEF) were independent predictors of better electrocardiographic ischemia grade (OR 0.4, 95% CI 0.17-0.90; P = 0.02, OR 0.92, 95% CI 0.85-0.99; P = 0.03, respectively) in multivariate logistic regression analysis. CONCLUSION PIA is one of the most important clinical predictors of better ischemia grades especially when combined with the pain to balloon time, LVEF, and admission CK-MB levels in patients with STEMI. This study provided another evidence for the protective effects of PIA.
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Affiliation(s)
- Turgay Celik
- Gulhane Military Medical Academy, School of Medicine, Department of Cardiology, Etlik, Ankara, Turkey.
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Abstract
The ECG is an essential part of the initial evaluation of patients who have chest pain, especially in the immediate decision-making process in patients who have ST-elevation myocardial infarction. This article reviews and summarizes the current information that can be obtained from the admission ECG in patients who have ST-elevation acute myocardial infarction, with an emphasis on: (1) prediction of final infarct size, (2) estimation of prognosis, and (3) the correlations between various ECG patterns and the localization of the infarct and the underlying coronary anatomy.
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Affiliation(s)
- Shaul Atar
- Division of Cardiology, University of Texas Medical Branch, 5.106 John Sealy Annex, 301 University Boulevard, Galveston, TX 77555, USA
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Billgren T, Maynard C, Christian TF, Rahman MA, Saeed M, Hammill SC, Wagner GS, Birnbaum Y. Grade 3 ischemia on the admission electrocardiogram predicts rapid progression of necrosis over time and less myocardial salvage by primary angioplasty. J Electrocardiol 2005; 38:187-94. [PMID: 16003698 DOI: 10.1016/j.jelectrocard.2005.03.010] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
BACKGROUND Among patients with ST-elevation acute myocardial infarction, those with terminal QRS distortion (grade 3 ischemia) have higher mortality and larger infarct size (IS) than patients without QRS distortion (grade 2 ischemia). METHODS We assessed the relation of baseline electrocardiographic ischemia grades to area at risk (AR) and myocardial salvage [100 (AR-IS)/AR] in 79 patients who underwent primary angioplasty for first ST-elevation acute myocardial infarction and had technetium Tc 99m sestamibi single-photon emission computed tomography before angioplasty (AR) and at predischarge (IS). Patients were classified as having grade 2 ischemia (ST elevation without terminal QRS distortion in any of the leads, n = 48), grade 2.5 ischemia (ST elevation with terminal QRS distortion in 1 lead, n = 16), or grade 3 ischemia (ST elevation with terminal QRS distortion in >2 adjacent leads, n = 15). RESULTS Time to treatment was comparable among groups. AR was comparable among groups (38% +/- 20%, 33% +/- 23%, and 34% +/- 23%, respectively; P = .70). There were no differences among groups in residual myocardial perfusion (severity index 0.28 +/- 0.12, 0.29 +/- 0.16, and 0.30 +/- 0.15 in grades 2, 2.5, and 3 ischemia, respectively; P = .97). In contrast, there was a trend toward lower myocardial salvage (45% +/- 32%) in the grade 3 group than in the grade 2 (65% +/- 33%) and grade 2.5 (65% +/- 40%) groups ( P = .16). Salvage was dependent on time only in the grade 3 group. Spearman rank correlation coefficients between time to treatment and percentage salvage were 0.003 ( P = .99), -0.24 ( P = .38), and -0.63 ( P = .022) for grades 2, 2.5, and 3, respectively. CONCLUSIONS Patients with grade 3 ischemia have rapid progression of necrosis over time and less myocardial salvage. This admission pattern is a predictor of myocardial salvage by primary angioplasty.
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Affiliation(s)
- Therese Billgren
- Division of Cardiology, The University of Texas Medical Branch, Galveston, TX 77555, USA
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23
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Yang HS, Lee CW, Hong MK, Moon DH, Kim YH, Lee SG, Han KH, Kim JJ, Park SW, Park SJ. Terminal QRS complex distortion on the admission electrocardiogram in anterior acute myocardial infarction and association with residual flow and infarct size after primary angioplasty. Korean J Intern Med 2005; 20:21-5. [PMID: 15906949 PMCID: PMC3891408 DOI: 10.3904/kjim.2005.20.1.21] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
BACKGROUND Terminal QRS complex distortion on admission is a simple and reliable predictor of infarct size in patients with acute myocardial infarction (AMI). It is uncertain, however, whether this reflects reduced myocardial perfusion of the infarct area and a larger area of the myocardium at risk. This study was conducted to investigate whether terminal QRS distortion complex on admission is a reliable predictor of reduced residual flow and a larger area of the myocardium at risk compared to patients who are admitted without a terminal QRS distortion. METHODS We evaluated the relationship between terminal QRS complex distortion and residual flow to the infarct zone and risk area in 46 anterior AMI patients undergoing primary angioplasty. (99m)Tc-sestamibi imaging was performed at baseline and 5-9 days after angioplasty. The study population was divided into those with (Group I, n=16) and without (Group II, n=30) terminal QRS complex distortion. RESULTS Baseline characteristics were similar between the two groups. The area of the myocardium at risk was higher in Group I (59.9 +/- 15.3%) than in Group 11 (48.6 +/- 13.7%, p < 0.05; mean+SD) while the nadir measurement of the residual flow was lower in Group I (0.10 +/- 0.07) than in Group 11 (0.16 +/- 0.09, p < 0.05). Although the final infarct size was significantly higher in Group I (40.8 +/- 17.2%) than in Group 11 (27.1 +/- 18.1%, p < 0.05), the myocardial salvage index did not differ significantly between the two groups. CONCLUSION Terminal QRS complex distortion seems to be associated with less residual flow to the infarct zone, a larger risk area and greater infarct size in patients with anterior AMI.
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Affiliation(s)
- Hyun Suk Yang
- Department of Internal Medicine, University of Ulsan College of Medicine, Asan Medical Center, Seoul, Korea
| | - Cheol Whan Lee
- Department of Internal Medicine, University of Ulsan College of Medicine, Asan Medical Center, Seoul, Korea
| | - Myeong-Ki Hong
- Department of Internal Medicine, University of Ulsan College of Medicine, Asan Medical Center, Seoul, Korea
| | - Dae-Hyuk Moon
- Department of Nuclear Medicine, University of Ulsan College of Medicine, Asan Medical Center, Seoul, Korea
| | - Young-Hak Kim
- Department of Internal Medicine, University of Ulsan College of Medicine, Asan Medical Center, Seoul, Korea
| | - Sang-Gon Lee
- Department of Internal Medicine, University of Ulsan College of Medicine, Asan Medical Center, Seoul, Korea
| | - Ki-Hoon Han
- Department of Internal Medicine, University of Ulsan College of Medicine, Asan Medical Center, Seoul, Korea
| | - Jae-Joong Kim
- Department of Internal Medicine, University of Ulsan College of Medicine, Asan Medical Center, Seoul, Korea
| | - Seong-Wook Park
- Department of Internal Medicine, University of Ulsan College of Medicine, Asan Medical Center, Seoul, Korea
| | - Seung-Jung Park
- Department of Internal Medicine, University of Ulsan College of Medicine, Asan Medical Center, Seoul, Korea
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24
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Sucu MM, Karadede A, Aydinalp O, Ozturk O, Toprak N. The Relationship Between Terminal QRS Complex Distortion and Early Low Dose Dobutamine Stress Echocardiography in Acute Anterior Myocardial Infarction. ACTA ACUST UNITED AC 2004; 45:373-86. [PMID: 15240958 DOI: 10.1536/jhj.45.373] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Although the damage in myocardial infarction has been demonstrated to be related with the magnitude and number of ST elevation, its relation with terminal distortion of QRS is unclear. The relationship between terminal QRS distortion in ECGs on admission and the results of early low dose dobutamine stress echocardiography (LDSE) performed 6 +/- 2 days later was investigated. Patients admitted to our clinic within the first six hours of their chest pain and without a prior infarction diagnosis were divided into two groups based on the admission electrocardiogram as the absence (QRS-, n = 33) or presence (QRS+, n = 29) of distortion of the terminal portion of the QRS in > or = 2 leads (QRS+; J point at > 50% of the R wave amplitude in lateral leads or presence of ST elevation without S wave in leads V1-V3). There were no significant differences between the groups with respect to thrombolytic therapy or reperfusion criteria. During LDSE, the infarct zone wall motion score index (WMSI) in the QRS- group was significantly decreased relative to baseline (from 2.93 +/- 0.65 to 2.37 +/- 0.84, P = 0.02), and it was significantly different compared with WMSI in the QRS+ group (P = 0.005). Improvement of akinetic regions to hypokinetic regions in the infarct zone (IZ) was found to be 33.5% (44/131) in the QRS- group and 17.8% (27/151 P = 0.004) in the QRS+ group. Furthermore, 55.1% (10/29) of the patients in the QRS+ group and only 18.1% (6/33) of those in the QRS- group did not respond to LDSE (P < 0.05). In multiple logistic regression analysis, while there was no relationship between good left ventricular functions (WMSI < 2) and terminal QRS distortion under basal conditions (P = 0.07), an independent relation was observed to exist between them after LDSE (P = 0.03, OR 4.48, 95% CI, 1.13-17.7). Moreover, plasma CK levels were higher in the QRS+ group (P = 0.03), whereas the ejection fraction was worse (P = 0.01). In both groups, there was no correlation between the Selvester score and left ventricle WMSI at baseline, but this correlation was significantly improved with LDSE (QRS-; r = 0.39 P = 0.02 and QRS+; r = 0.44 P = 0.01) The viability in the IZ is relatively less in those patients with terminal QRS distortion observed in their ECG on admission. This simple classification would be useful in predicting left ventricular function at the time of discharge.
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Affiliation(s)
- Mehmet Murat Sucu
- Department of Cardiology, Faculty of Medicine, Dicle University, Diyarbakir, Turkey
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25
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Chuck ET, Meyers K, France D, Creazzo TL, Morley GE. Transitions in ventricular activation revealed by two-dimensional optical mapping. ACTA ACUST UNITED AC 2004; 280:990-1000. [PMID: 15372433 DOI: 10.1002/ar.a.20083] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
While cardiac function in the mature heart is dependent on a properly functioning His-Purkinje system, the early embryonic tubular heart efficiently pumps blood without a distinct specialized conduction system. Although His-Purkinje system precursors have been identified using immunohistological techniques in the looped heart, little is known whether these precursors function electrically. To address this question, we used high-resolution optical mapping and fluorescent dyes with two CCD cameras to describe the motion-corrected activation patterns of 76 embryonic chick hearts from tubular stages (stage 10) to mature septated hearts (stage 35). Ventricular activation in the tubular looped heart (stages 10-17) using both calcium-sensitive fluo-4 and voltage-sensitive di-4-ANEPPS shows sequentially uniform propagation. In late looped hearts (stages 18-22), domains of the dorsal and lateral ventricle are preferentially activated before spreading to the remaining myocardium and show alternating regions of fast and slow propagation. During stages 22-26, action potentials arise from the dorsal ventricle. By stages 27-29, action potential breakthrough is also observed at the right ventricle apex. By stage 31, activation of the heart proceeds from foci at the apex and dorsal surface of the heart. The breakthrough foci correspond to regions where putative conduction system precursors have been identified immunohistologically. To date, our study represents the most detailed electrophysiological characterization of the embryonic heart between the looped and preseptated stages and suggests that ventricular activation undergoes a gradual transformation from sequential to a mature pattern with right and left epicardial breakthroughs. Our investigation suggests that cardiac conduction system precursors may be electrophysiologically distinct and mature gradually throughout cardiac morphogenesis in the chick.
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Affiliation(s)
- Emil Thomas Chuck
- Neonatal-Perinatal Research Institute, Division of Neonatology, Department of Pediatrics and Department of Cell Biology, Duke University Medical Center, Durham, North Carolina, USA
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26
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Birnbaum Y, Drew BJ. The electrocardiogram in ST elevation acute myocardial infarction: correlation with coronary anatomy and prognosis. Postgrad Med J 2003; 79:490-504. [PMID: 13679544 PMCID: PMC1742828 DOI: 10.1136/pmj.79.935.490] [Citation(s) in RCA: 58] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
The electrocardiogram is considered an essential part of the diagnosis and initial evaluation of patients with chest pain. This review summarises the information that can be obtained from the admission electrocardiogram in patients with ST elevation acute myocardial infarction, with emphasis on: (1) prediction of infarct size, (2) estimation of prognosis, and (3) the correlations between various electrocardiographic patterns and the localisation of the infarct and the underlying coronary anatomy.
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Affiliation(s)
- Y Birnbaum
- University of Texas Medical Branch, Galveston, Texas 77555-0553, USA.
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27
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Lee CW, Hong MK, Yang HS, Choi SW, Kim JJ, Park SW, Park SJ. Determinants and prognostic implications of terminal QRS complex distortion in patients treated with primary angioplasty for acute myocardial infarction. Am J Cardiol 2001; 88:210-3. [PMID: 11472695 DOI: 10.1016/s0002-9149(01)01627-7] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Terminal QRS complex distortion on admission has an impact on a patient's prognosis after primary angioplasty for acute myocardial infarction (AMI). We evaluated the determinants and prognostic significance of terminal QRS complex distortion in 153 consecutive patients with AMI after primary angioplasty. The study population was divided into 2 groups according to the presence (group I, n = 41) or absence (group II, n = 112) of terminal QRS complex distortion. The primary end points were the occurrence, within 6 weeks after AMI, of death, nonfatal reinfarction, or congestive heart failure. Baseline characteristics were similar between the 2 groups. However, patients in group I had higher peak levels of serum creatine kinase than those in group II (5,100 +/- 3,100 vs 3,000 +/- 1,800 U/L, respectively, p <0.01). The rate of angiographic no-reflow (Thrombolysis In Myocardial Infarction flow grade < or =2) was 31.7% in group I and 10.7% in group II (p <0.01). The predischarge left ventricular ejection fraction was 45.0 +/- 12.0% in group I and 54.0 +/- 8.0% in group II (p <0.01). Multivariate analysis identified the pressure-derived fractional collateral flow index and the culprit lesion in the left anterior descending coronary artery as independent determinants of the terminal QRS complex distortion. No patients died during 6 weeks of follow-up. The 2 groups were similar for life-threatening arrhythmia or reinfarction. However, there were more patients in group I than in group II with congestive heart failure (26.8% vs 5.4%, respectively, p <0.01) or who reached the primary end points (29.3% vs 5.4%, respectively, p <0.01). In conclusion, terminal QRS complex distortion on admission is associated with poor clinical outcome after primary angioplasty for AMI, and collateral flow may have a major influence on terminal QRS complex distortion during AMI.
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Affiliation(s)
- C W Lee
- Department of Medicine, Asan Medical Center, University of Ulsan, Seoul, South Korea
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28
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Inoue K, Ito H, Kitakaze M, Kuzuya T, Hori M, Iwakura K, Nishikawa N, Higashino Y, Fujii K, Minamino T. Antecedent angina pectoris as a predictor of better functional and clinical outcomes in patients with an inferior wall acute myocardial infarction. Am J Cardiol 1999; 83:159-63. [PMID: 10073814 DOI: 10.1016/s0002-9149(98)00817-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
We examined whether angina pectoris (AP) occurring shortly before the onset of acute myocardial infarction (AMI) can render the right ventricle and the conducting tissue resistant to ischemia in 75 patients with an inferior wall AMI. Each patient had total occlusion in the proximal right coronary artery and underwent successful coronary angioplasty < or =24 hours from the onset. We divided patients into 2 groups based on presence or absence of antecedent AP < or =24 hours before the system onset: group 1 (absent) = 57 patients; group 2 (present) = 18 patients. Collateral circulation was more frequently observed in group 2 than in group 1 (group 1 vs 2, 28% vs 61%, p <0.01). Elevation in ST segment > or =1 mm in lead V4R, hemodynamic right ventricular dysfunction, and frequency of high-degree heart block were more frequent in group 1 than in group 2 (75% vs 44%, 79% vs 39%, 53% vs 11%, p <0.05, respectively). Multivariate analysis demonstrated that antecedent AP is the only factor related to these complications. Thus, episodes of AP occurring shortly before onset may restrain development of ischemic damage of the right ventricle and conducting tissue, and are associated with better clinical and functional outcomes among patients with an inferior wall AMI.
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Affiliation(s)
- K Inoue
- Sakurabashi Watanabe Hospital, The First Department of Medicine, Osaka University School of Medicine, Japan
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29
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Birnbaum Y, Herz I, Sclarovsky S, Zlotikamien B, Chetrit A, Olmer L, Barbash GI. Admission clinical and electrocardiographic characteristics predicting an increased risk for early reinfarction after thrombolytic therapy. Am Heart J 1998; 135:805-12. [PMID: 9588409 DOI: 10.1016/s0002-8703(98)70038-9] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
BACKGROUND This study assessed the ability of clinical and electrocardiographic variables routinely obtained on admission to identify patients with acute myocardial infarction treated with thrombolytic therapy at risk of early reinfarction. METHODS AND RESULTS The study included 2602 patients who received thrombolytic therapy for acute myocardial infarction. Baseline demographic variables and admission clinical and electrocardiographic variables were compared between patients with and without reinfarction. Multivariable logistic regression technique was used and included recurrent infarction as the dependent variable, and baseline demographic, clinical, and electrocardiographic variables as independent variables. History of hypertension (odds ratio [OR] 1.52, 95% confidence interval [CI] 1.00 to 2.31) and diabetes mellitus (OR 1.59, 95% CI 1.00 to 2.53) were associated with a higher risk, and current smoking was associated with a lower risk (OR [no versus yes] 1.64, 95% CI 1.05 to 2.58) of early hospital reinfarction. Distortion of the terminal portion of the QRS complex (OR 1.86, 95% CI 1.20 to 2.87) and absence of abnormal Q waves on admission (OR 1.54, 95% CI 0.98 to 2.43) were associated with increased risk of early reinfarction. CONCLUSIONS A simple electrocardiographic sign is a reliable predictor of early reinfarction among patients who receive thrombolytic therapy for acute myocardial infarction.
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Affiliation(s)
- Y Birnbaum
- Beilinson Medical Center, Sackler Faculty of Medicine, Tel Aviv University, Petah-Tiqua, Israel
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30
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Birnbaum Y, Hale SL, Kloner RA. Changes in R wave amplitude: ECG differentiation between episodes of reocclusion and reperfusion associated with ST-segment elevation. J Electrocardiol 1997; 30:211-6. [PMID: 9261729 DOI: 10.1016/s0022-0736(97)80006-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
This study assesses the electrocardiographic (ECG) differences between episodes of increased ST-segment amplitude induced by coronary artery occlusion and by reperfusion in the open-chest rabbit model. Nine anesthetized open-chest male New Zealand White rabbits were subjected to four episodes of 5 minutes of coronary artery occlusion followed by 5 minutes of reperfusion. The ST-segment and R wave amplitudes were measured from an ECG lead attached to the pericardium overlying the ischemic myocardium. In 10 out of 35 (29%) of the episodes, reperfusion resulted in a transient increase in ST-segment amplitude. While episodes of coronary artery occlusion were associated with increase in R wave amplitude (69% and 97% of the episodes after 1 and 5 minutes, respectively), all reperfusion episodes were associated with prompt decrease in R wave amplitude. There was no difference between the repeated episodes in the occurrence of ST-segment elevation during reperfusion. However, ST-segment elevation during reperfusion could be distinguished from the ischemic episodes by the prompt decline in the R wave amplitude in the former compared with no change or increase in the latter.
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Affiliation(s)
- Y Birnbaum
- Heart Institute, Good Samaritan Hospital, Los Angeles, California 90017, USA
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31
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Birnbaum Y, Kloner RA, Sclarovsky S, Cannon CP, McCabe CH, Davis VG, Zaret BL, Wackers FJ, Braunwald E. Distortion of the terminal portion of the QRS on the admission electrocardiogram in acute myocardial infarction and correlation with infarct size and long-term prognosis (Thrombolysis in Myocardial Infarction 4 Trial). Am J Cardiol 1996; 78:396-403. [PMID: 8752182 DOI: 10.1016/s0002-9149(96)00326-8] [Citation(s) in RCA: 71] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Previous studies have shown an association between distortion of the terminal portion of the QRS (QRS[+] pattern: emergence of the J point > or = 50%. of the R wave in leads with qR configuration or disappearance of the S wave in leads with an Rs configuration) on admission and in-hospital mortality in acute myocardial infarction (AMI). However, the mechanism for this association is not known. We assessed the relation between QRS(+) pattern and coronary angiographic findings, infarct size, and long-term prognosis in the Thrombolysis In Myocardial Infarction 4 trial. Patients were allocated into 2 groups based on the presence (QRS[+], n = 85) or absence (QRS[-], n = 293) of QRS distortion. The QRS(+) patients were older (mean +/- SD: 61.1 +/- 10.6 vs 57.5 +/- 10.6 years, p = 0.004), had more anterior AMI (49% vs 37%, p = 0.04), and less previous angina (42% vs 54%, p = 0.05). QRS(+) patients had larger infarct size as assessed by creatine kinase release over 24 hours (209 +/- 147 vs 155 +/- 129, p = 0.003), and predischarge sestamibi (MIBI) defect (17.9 +/- 15.9% vs 11.2 +/- 13.4%, p <0.001). When adjusting for difference in baseline characteristics, p values for the differences in 24-hour creatine kinase release were 0.03 and 0.64 for anterior and nonanterior AMI, respectively, and for MIBI defect size 0.03 and 0.02, respectively. One-year mortality (18% vs 6%, p = 0.03) was higher and the weighted end point of death, reinfarction, heart failure, or left ventricular ejection fraction <40% (0.33 +/- 0.37 vs 0.24 +/- 0.32, p = 0. 13), tended to be higher in the anterior AMI patients with QRS(+). No difference in clinical outcome was found in patients with non-anterior AMI. These findings suggest that this simple electrocardiographic definition of presence of QRS(+) pattern on admission may provide an early estimation of infarct size and long-term prognosis, especially in anterior AMI.
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Affiliation(s)
- Y Birnbaum
- The Heart Institute, Good Samaritan Hospital, Los Angeles, California, USA
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Birnbaum Y, Herz I, Sclarovsky S, Zlotikamien B, Chetrit A, Olmer L, Barbash GI. Prognostic significance of the admission electrocardiogram in acute myocardial infarction. J Am Coll Cardiol 1996; 27:1128-32. [PMID: 8609331 DOI: 10.1016/0735-1097(96)00003-4] [Citation(s) in RCA: 105] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
OBJECTIONS We sought to access the ST segment and the terminal portion of the QRS complex in the initial electrocardiogram (ECG) as tools to predict outcome in patients with acute myocardial infarction given thrombolytic therapy. BACKGROUND Previous studies assessing early risk stratification of patients with acute myocardial infarction by ECG criteria have focused on the number of leads with ST segment elevation or the absolute magnitude of ST deviation. A new classification independent of the absolute values of ST deviation was pursued. METHODS Patients with ST elevation and positive T waves in at least two adjacent leads who received thrombolytic therapy were classified into two groups based on the absence (1,232 patients) or presence (1,371 patients) of distortion of the terminal portion of the QRS complex on the admission ECG. RESULTS There were no differences between groups in the prevalence of previous angina, hypertension, current smoking, anterior infarction, time from onset of symptoms to therapy of type of thrombolytic regimen. Patients with QRS distortion were less likely to have had a previous infarction (12.0% vs. 18.4%, p = 0.02) or diabetes mellitus (16.9% vs. 21.4%, p = 0.003). They had higher peak creatine kinase levels (1,617 +/- 1,670 vs. 1,080 +/- 1,343 IU, p = 0.00001). Hospital mortality for those with and without QRS distortion was 6.8% and 3.8%, respectively (p = 0.0008). Multivariable logistic regression analysis confirmed that hospital mortality was independently associated with distortion of terminal portion of the QRS complex (odds ratio 1.78, 95% confidence interval 1.19 to 2.68, p = 0.004). CONCLUSIONS Distortion of the terminal portion of the QRS complex on the admission ECG is independently associated with a higher hospital mortality rate in patients with acute myocardial infarction given thrombolytic therapy.
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Affiliation(s)
- Y Birnbaum
- Beilinson Medical Center, Petah-Tiqva, Israel
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33
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Birnbaum Y, Sclarovsky S, Hasdai D, Burstein I, Kusniec J, Strasberg B. ST segment reelevation after acute myocardial infarction: marked differences in the electrocardiographic pattern between early and late episodes. Int J Cardiol 1995; 48:49-57. [PMID: 7744538 DOI: 10.1016/0167-5273(94)02216-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
This study assesses the electrocardiographic (ECG) morphologic differences between early (< 24 h) and late (> 24 h) episodes of ST segment reelevation after acute myocardial infarction. We studied the records of 101 consecutive patients with acute myocardial infarction whose admission ECG demonstrated ST segment elevation with positive T waves, without pathological Q waves in the relevant leads, and without signs of bundle branch block or left ventricular hypertrophy. Thirty-five patients had 44 episodes of early ST segment reelevation, while 22 patients experienced 26 late episodes of ST segment reelevation. Seven patients experienced both early and late episodes. Early episodes of ST segment reelevation was seen more often after thrombolytic therapy: 43% (32 of 74 patients) versus 11% (3 of 27 patients) (P < 0.006). No differences were found in the incidence of late episodes between those who underwent (23%) or did not undergo (19%) thrombolytic therapy. Two patterns of ST segment elevation were distinguished. Pattern A with positive T waves, ST segment elevation (> or = 0.1 mV), but without distortion of the terminal portion of the QRS complex. Pattern B characterized by positive T waves, ST segment elevation (> or = 0.1 mV) with distortion of the terminal portion of the QRS complex. Each ECG was categorized according to these two patterns. The admission ECG pattern was A in 75 patients, and B in 26. No significant differences were found between patients with early, late, or no episodes of ST segment reelevation in the appearance of pattern A or B on admission.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- Y Birnbaum
- Department of Cardiology, Beilinson Medical Center, Petah-Tiqva, Israel
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35
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Birnbaum Y, Sclarovsky S, Strasberg B, Kusniec J. Polymorphous ventricular tachycardia in the early stages of an evolving myocardial infarction. J Basic Clin Physiol Pharmacol 1993; 4:347-56. [PMID: 8664251 DOI: 10.1515/jbcpp.1993.4.4.347] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Affiliation(s)
- Y Birnbaum
- Department of Cardiology, Beilinson Medical Center, Petah Tiqva, Israel
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36
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Birnbaum Y, Sclarovsky S, Blum A, Mager A, Gabbay U. Prognostic significance of the initial electrocardiographic pattern in a first acute anterior wall myocardial infarction. Chest 1993; 103:1681-7. [PMID: 8141879 DOI: 10.1378/chest.103.6.1681] [Citation(s) in RCA: 77] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
The availability of potent, but potentially dangerous, types of reperfusion therapy for acute myocardial infarction (AMI) has forced us to refine our tools for early and accurate diagnosis and for early risk stratification of patients with evolving AMI. The estimation of risk has to be made shortly after admission, when only the history, physical examination, and the ECG are available. This study was undertaken to compare in-hospital mortality with different patterns of the ECG obtained at admission in 147 consecutive patients with an evolving first AMI of the anterior wall. By using a new classification of the admission ECG, it was possible to divide the patients into 3 groups: (1) group A contained 12 patients with tall peaked T waves in the involved leads, without ST segment elevation; (2) group B comprised 77 patients with abnormal T waves and ST elevation, but without major changes in the terminal portion of the QRS complex; and (3) group C comprised 58 patients with abnormal T waves, ST elevation, and distortion of the terminal portion of the QRS. The mortality was 0, 3 percent, and 29 percent in groups A, B, and C, respectively (chi 2 = 22.91; p = 0). By using a logistic regression model, it was found that the initial ECG pattern alone is a strong predictor of in-hospital mortality in patients with an evolving anterior wall AMI. The predicted probabilities of death in groups A, B, and C are 0.0016, 0.025, and 0.29, respectively. This simple classification of the initial ECG pattern in patients with a first AMI of the anterior wall may enable the differentiation of patients with low in-hospital mortality (groups A and B) and of those with an in-hospital mortality of almost 30 percent (group C).
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Affiliation(s)
- Y Birnbaum
- Israel and Ione Massada Center for Heart Diseases, Beilinson Medical Center, Petah Tikva, Israel
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37
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Watanabe M, Timm M, Fallah-Najmabadi H. Cardiac expression of polysialylated NCAM in the chicken embryo: correlation with the ventricular conduction system. Dev Dyn 1992; 194:128-41. [PMID: 1421523 DOI: 10.1002/aja.1001940206] [Citation(s) in RCA: 29] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
The neural cell adhesion molecule (NCAM) and its polysialic acid moeity (PSA) affect cellular interactions during the development of the nervous system and skeletal muscle. NCAM has also been identified in the embryonic heart of various species including humans. However, knowledge regarding the role of NCAM and its function-modulating PSA in cardiogenesis is limited. The distribution of NCAM and its PSA in the ventricular myocardium of chicken embryos was determined by indirect immunofluorescence staining. The NCAM polypeptide was found throughout the cardiac myocardium. In contrast PSA was located in discrete regions in stage 20 to 44 embryos (during and after septation). Myocardium at the subendocardial regions of the atrioventricular canal and ventricular trabeculae were PSA positive by stage 20. At later stages, transverse sections of the postseptation heart just below the level of the atrioventricular interface revealed a PSA-positive bundle of myocardium in the septum. This bundle was continuous with two branches at a more apical level which in turn were continuous with the PSA-positive subendocardial myocardium lining the left and right ventricles. This pattern of PSA in the myocardium was similar to that of the ventricular conduction system configuration defined in the adult heart. Electron micrographs of the subendocardium of the ventricular septum revealed PSA positivity on myofibril-containing cells with the ultrastructural location of Purkinje fibers. At later stages (35-44) a subset of cells within PSA-positive regions was stained by an antibody against an isoform of the myosin heavy chain found in adult Purkinje fibers. These cells and surrounding tissue lacked PSA in the adult heart. Thus polysialylated NCAM may be modulating cell-cell interactions during the development of the ventricular conduction system.
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Affiliation(s)
- M Watanabe
- Department of Pediatrics, Rainbow Babies and Childrens Hospital, Case Western Reserve University, School of Medicine, Cleveland, Ohio 44106-4901
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38
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Doménech-Mateu JM, Arnó-Palau A, Martínez-Pozo A. Study of the development of the atrioventricular conduction system as a consequence of observing an extra atrioventricular node in the normal heart of a human fetus. Anat Rec (Hoboken) 1991; 230:73-85. [PMID: 2064030 DOI: 10.1002/ar.1092300108] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
We have observed an extra atrioventricular node in the normal heart of a human fetus. It is located in the septal wall of the right atrium, subendocardially, and just where Todaro's tendon leaves this wall to go toward the inferior vena cava valve. In its trajectory, this tendon gives way to a remarkable prominence in the cavity of the right atrium: the sinus band. In order to explain the embryogenesis of this extra atrioventricular node, we have studied the normal development of the atrioventricular specific system and have concluded that the atrioventricular node is formed from a growth and displacement toward the atrium of the primitive atrioventricular specific material, which originates from the myocardium of the posterior wall of the atrioventricular canal. Likewise, during its development, the atrioventricular node keeps in close proximity with the Todaro's tendon. In our view, this accounts for the embryogenesis of the extra atrioventricular node, since a fragment of the atrioventricular node can remain cranial to Todaro's tendon and be displaced by it in a craniodorsal direction. This fragment would then lead to the formation of an extra atrioventricular node like the one present in the heart of the fetus we have examined.
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Affiliation(s)
- J M Doménech-Mateu
- Faculty of Medicine, Department of Anatomy, Autonomous University of Barcelona, Bellaterra, Spain
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39
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Sneddon JF, Ward DE, Simpson IA, Linker NJ, Wainwright RJ, Camm AJ. Alcohol ablation of atrioventricular conduction. Heart 1991; 65:143-7. [PMID: 2015122 PMCID: PMC1024536 DOI: 10.1136/hrt.65.3.143] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Transcoronary ablation of atrioventricular conduction by dehydrated alcohol was attempted in 14 patients with refractory atrial arrhythmias. Alcohol (0.5 or 1.0 ml) was delivered after selective catheterisation of the atrioventricular nodal artery in the 10 patients in whom the artery could be identified by cineangiography. The other four patients underwent electrical ablation when the nodal artery could not be catheterised. Temporary atrioventricular block induced by dilute contrast and cold saline (0.9%) confirmed that the catheter was in the correct position before the alcohol was delivered. In all 10 patients complete atrioventricular block developed after alcohol ablation. The block persisted in all four patients given 1.0 ml alcohol but not in four of the six given 0.5 ml. The mean (SD) creatine kinase (MB fraction) at four to six hours after ablation was 76.5 (49.5) IU after 1.0 ml and 75.5 (43.1) IU after 0.5 ml alcohol (normal less than 20 IU). The overall success rate of alcohol ablation in the whole group on an "intention to treat" basis was 43%. The procedure was a technical success in six of the 10 patients in whom the nodal artery was identified. Transcoronary alcohol ablation of atrioventricular conduction should be considered in patients in whom electrical techniques have been unsuccessful.
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Affiliation(s)
- J F Sneddon
- Department of Cardiological Sciences, St George's Hospital Medical School, London
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40
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Lamers WH, Geerts WJ, Moorman AF. Distribution pattern of acetylcholinesterase in early embryonic chicken hearts. Anat Rec (Hoboken) 1990; 228:297-305. [PMID: 2260785 DOI: 10.1002/ar.1092280309] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
To study the developmental appearance of acetylcholinesterase in early embryonic hearts, an enzyme-histochemical study was carried out in chicken embryos ranging from cardiogenic plate to late tubular stages. Initially acetylcholinesterase is present in all cells of the (future) myocardium. When 13-14 pairs of somites have developed, i.e., shortly before blood propulsion starts, acetylcholinesterase selectively disappears from the ventral and lateral wall of the developing ventricle. Slightly later, when 18-19 pairs of somites have developed, acetylcholinesterase also disappears from the dorsal and anterior wall of the atrium. High concentrations of acetylcholinesterase remain present in the outflow tract and lower concentrations in a continuous tract along the lesser curvature of the heart, the atrial side of the atrioventricular canal, and the left wall of the atrium. In late tubular stages of heart development, acetylcholinesterase is reexpressed in the inner myocardial layer of the ventricle, i.e., in the developing trabeculae and the ventricular side of the atrioventricular canal, where it is continuous with the acetylcholinesterase-expressing cells of the atrial side of the atrioventricular canal. The expression pattern of acetylcholinesterase in early embryonic chick hearts coincides with that of areas that control the conduction of the impulse and may reveal a cholinergic signal transduction system that is responsible for a coordinated contraction pattern of the myocardium prior to the development of the definitive conductive system.
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Affiliation(s)
- W H Lamers
- Department of Anatomy and Embryology, University of Amsterdam, The Netherlands
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41
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Affiliation(s)
- P B Berger
- Evans Memorial Department of Clinical Research, University Hospital, Boston, Massachusetts
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42
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Transient alterations of the QRS complex and ST segment during percutaneous transluminal balloon angioplasty of the left anterior descending coronary artery. Am J Cardiol 1988; 62:1038-42. [PMID: 2973217 DOI: 10.1016/0002-9149(88)90544-9] [Citation(s) in RCA: 103] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Using continuous 3-lead electrocardiographic (ECG) recordings in 19 patients undergoing elective percutaneous transluminal coronary artery angioplasty (PTCA) of the left anterior descending (LAD) artery, this study described the dynamic changes of the ST segment and the R- and S-wave amplitudes that occur during transient myocardial ischemia. The waveforms from lead V2 were quantified at 10-second intervals during the length of the balloon inflation that produced the greatest extent of ST-segment deviation. The simultaneous changes that occurred in leads aVF and V5 were also observed, but not quantified. Measurements of R- and S-wave amplitudes were performed during maximal ischemia from both the PR- and the J-ST-segment baselines to determine which of these most nearly maintained its control position during ischemia. The results indicate that the R-wave amplitude is best determined from the PR-segment baseline (p = 0.0007), while the S wave is best determined from the J-ST-segment baseline (p = 0.03). However, only a portion of the QRS changes observed during PTCA could be accounted for by the baseline shift. There were additional QRS changes during ischemia in 11 of the patients (58%) suggestive of conduction disturbances in 3 endocardial sites: left septal, right septal and left anterosuperior. It is hypothesized that these changes may represent ischemia-induced delay in conduction ("periischemic block") previously thought to occur only with myocardial infarction.
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43
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de Jong F, Geerts WJ, Lamers WH, Los JA, Moorman AF. Isomyosin expression patterns in tubular stages of chicken heart development: a 3-D immunohistochemical analysis. ANATOMY AND EMBRYOLOGY 1987; 177:81-90. [PMID: 3439639 DOI: 10.1007/bf00325291] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
The 3-D distribution of atrial and ventricular isomyosins is analysed in tubular chicken hearts (stage 12+ to 17 (H/H)) using antibodies specific for adult chicken atrial and ventricular myosin heavy chains, respectively. At stage 12+ (H/H) all myocytes express the atrial isomyosin; furthermore, all myocytes except those originally situated in the dorsolateral wall of the sinu-atrium coexpress the ventricular isomyosin as well. Moreover, it appears that recently incorporated myocardial cells at both ends of the heart tube start with a coexpression of both isomyosins. From stage 14 (H/H) onwards a regional loss of expression of one of either isomyosins is observed in the atrial and ventricular compartment. In this way the single isomyosin expression types that are characteristic for the adult working myocardium of the atria and ventricles arise. So, the isomyosin expression patterns are, unexpectedly, hardly useful to discriminate the different heart parts of the tubular heart. The ventricle, defined by its adult type of isomyosin expression, is even not detectable before stage 14 (H/H). Interestingly, interconnected coexpression areas, which may be precursor conductive tissues, are still present at stage 17 (H/H) in the outflow tract, the ventricular trabeculae, the atrio-ventricular transitional zone and in the sinu-atrium. The pattern of isomyosin coexpression was found to correlate with a peristaltoid contraction and a slow conduction velocity, whereas single expression areas correlate with a synchronous contraction and a relatively fast conduction velocity. The possible implications of the changing isomyosin pattern for the differentiation of the tubular myocardium, in particular in relation to the development of the conductive tissues, will be discussed.
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Affiliation(s)
- F de Jong
- Department of Anatomy and Embryology, University of Amsterdam, The Netherlands
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44
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Ellis D, Noireaud J. Intracellular pH in sheep Purkinje fibres and ferret papillary muscles during hypoxia and recovery. J Physiol 1987; 383:125-41. [PMID: 3656122 PMCID: PMC1183061 DOI: 10.1113/jphysiol.1987.sp016400] [Citation(s) in RCA: 47] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
1. The changes of intracellular pH (pHi) of papillary muscles from ferret and Purkinje fibres from sheep heart during hypoxia and recovery from hypoxia were recorded with pH-sensitive micro-electrodes filled with neutral H+ carrier. 2. Hypoxia was produced by replacement of O2 with N2 in the superfusing solutions. When oxidative phosphorylation was prevented, developed tension fell within 20 min to about 16 and 21% of its control value for papillary muscle and Purkinje fibres respectively. On restoration of O2, recovery of developed tension in ferret papillary muscle is preceded by a transient additional decrease. 3. In ferret papillary muscle, the pHi first increased by a mean value of 0.11 pH units after 3 min hypoxia, then decreased by about 0.24 pH units after 20 min. In sheep Purkinje fibres, the initial alkalosis was small or absent, and after 5-9 min, the pHi started to fall reaching 0.17 pH units after 20 min of hypoxia. On return to oxygenated solution, a transient additional intracellular acidification occurred. This acidification reached its peak of 0.31 pH units in papillary muscle and of 0.13 pH units in Purkinje fibres. In both preparations hypoxia was accompanied by a depolarization of a few millivolts. 4. The presence of cyanide (1-2 mM) or fluorodinitrobenzene (20-40 microM) prevented the additional intracellular acidification occurring on return to oxygenated solution. Removal of cyanide itself produced a transient but smaller and slower acidification. 5. On both preparations, exposure to a Tyrode solution containing 10 mM-L-lactate produced a transient intracellular acidification. After recovery from this acidification the acidification produced by hypoxia was increased without affecting the extra acidification on reintroduction of O2. 6. After reduction of the rate of glycolysis by removal of glucose and application of 2-deoxyglucose, the transient intracellular acidification, occurring on return to oxygenated solution after hypoxia, was inhibited in both preparations. In ferret papillary muscle, insulin (100 mU/ml) potentiated the changes of pHi occurring during hypoxia. 7. Using Na+-sensitive glass micro-electrodes it was found that the intracellular Na+ activity rose slightly during the later stages of hypoxia and rose transiently on readdition of O2. These results are consistent with a Na+-H+ exchange being stimulated by acidosis. 8. The origins of the pH changes during and after hypoxia are discussed as are the differences between the responses of sheep Purkinje fibres and ferret papillary muscle.
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Affiliation(s)
- D Ellis
- Department of Physiology, University Medical School, Edinburgh
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45
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González-Sánchez A, Bader D. Characterization of a myosin heavy chain in the conductive system of the adult and developing chicken heart. J Cell Biol 1985; 100:270-5. [PMID: 3880754 PMCID: PMC2113473 DOI: 10.1083/jcb.100.1.270] [Citation(s) in RCA: 62] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
A monoclonal antibody (anterior latissimus dorsi 58 [ALD58]; antimyosin heavy chain, MHC) directed against myosin from slow tonic muscle was found to react specifically with the striated muscle cells of the conductive system in the adult chicken heart. This monoclonal antibody was used to study the expression of myosin in the conductive system of the adult and developing heart. Using immunofluorescence microscopy with ALD58, muscle cells of the conductive system were demonstrated in both the atria and ventricles of the adult heart as previously shown by Sartore et al. (Sartore, S., S. Pierobon-Bormioli, and S. Schiafinno, 1978, Nature (Lond.), 274: 82-83). Radioactive myosin from adult atria and ventricles was precipitated with ALD58 and subjected to limited proteolysis and subsequent peptide mapping. Peptide maps of ALD58 reactive myosin from atria and ventricles were very similar, if not identical, but differed from peptide maps of ordinary atrial and ventricular myosin. The same antibody was used to study cardiac myogenesis in the chick embryo. When ALD58 was reacted with myosin isolated from atria and ventricles at selected stages of development in radioimmunoassays, reactivity was not observed until the last week of embryonic life (greater than 15 d of egg incubation). Thereafter concomitant and progressively increased reactivity was observed in atrial and ventricular preparations. Also, no ALD58 positive cells were observed in immunofluorescence studies of embryonic hearts until 17 d of egg incubation. Primary cell cultures of embryonic hearts also proved to be negative for this antibody. This study demonstrates that an epitope recognized by ALD58 associated with an antimyosin heavy chain of striated muscle cells of the adult heart conductive system is absent or present in only small amounts in the early embryonic heart.
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Forsgren S, Strehler E, Thornell LE. Differentiation of Purkinje fibres and ordinary ventricular and atrial myocytes in the bovine heart: an immuno- and enzyme histochemical study. THE HISTOCHEMICAL JOURNAL 1982; 14:929-42. [PMID: 6816763 DOI: 10.1007/bf01005234] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
The differentiation of Purkinje fibres and ordinary ventricular and atrial myocytes in bovine hearts was studied with specific antibodies against M-line proteins (MM-creatine kinase and myomesin) and with enzyme histochemistry (succinate dehydrogenase and mitochondrial glycerol-3-phosphate dehydrogenase). MM-creatine kinase was detected at an earlier stage in Purkinje fibres and atrial myocytes than in ordinary ventricular myocytes. The findings are in agreement with previous ultrastructural observations that an earlier appearance of a dense M-band occurs in Purkinje fibres than in ordinary ventricular myocytes. Myomesin was detected in all three cell types even at early foetal stages, in accordance with suggestions that it is an integral component of the myofibrillar structure. The activity of succinate dehydrogenase gradually increased in both ordinary ventricular and atrial myocytes, while the activity of mitochondrial glycerol-3-phosphate dehydrogenase was high at different stages of early foetal development in the two tissues, finally becoming low in the adult stage. The activity of succinate dehydrogenase and mitochondrial glycerol-3-phosphate dehydrogenase seemed to remain unchanged in the Purkinje fibres from early to late foetal stages. The present study shows that the Purkinje fibres are already different from ordinary ventricular myocytes at early foetal stages and that the two cell types differentiate in different ways. It is concluded that there are also developmental differences between ordinary ventricular and atrial myocytes.
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47
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Hoerter J. Changes in the sensitivity to hypoxia and glucose deprivation in the isolated perfused rabbit heart during perinatal development. Pflugers Arch 1976; 363:1-6. [PMID: 946903 DOI: 10.1007/bf00587394] [Citation(s) in RCA: 47] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
The isometric contraction of the isolated rabbit myocardium was measured from 24 days post coitum (dpc) to young adulthood. Tension per gram of heart as developed by the isolated perfused hearts remained constant during late foetal life but increased during the first postnatal week. Sensitivity to hypoxia rapidly increased during foetal life from 26 to 28 days post coitum. In young foetal hearts (up to 28 days post coitum), contraction continued for several hours in the absence of glucose. In contrast, from 28 days post coitum onwards foetal hearts became increasingly dependent on external glucose to maintain their contractility. This change was concomitant with a decrease in myocardial glycogen content. Intracellular electrical activity recorded in the absence of glucose showed that during hypoxia in the foetus at term were reduced, whereas normal activity continued in the same hypoxic glucose-free medium in hearts from foetuses 26 days post coitum. The relative role of glycolysis and oxidative metabolism is discussed and the importance of glycogenolytic metabolism in young isolated foetal hearts is pointed out.
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Czarnecki CM. A histologic study of the developing conduction system in the turkey heart. Poult Sci 1973; 52:1428-39. [PMID: 4589751 DOI: 10.3382/ps.0521428] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
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