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La Rovere MT, Porta A, Schwartz PJ. Autonomic Control of the Heart and Its Clinical Impact. A Personal Perspective. Front Physiol 2020; 11:582. [PMID: 32670079 PMCID: PMC7328903 DOI: 10.3389/fphys.2020.00582] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2019] [Accepted: 05/11/2020] [Indexed: 12/21/2022] Open
Abstract
This essay covers several aspects of the autonomic control of the heart, all relevant to cardiovascular pathophysiology with a direct impact on clinical outcomes. Ischemic heart disease, heart failure, channelopathies, and life-threatening arrhythmias are in the picture. Beginning with an overview on some of the events that marked the oscillations in the medical interest for the autonomic nervous system, our text explores specific areas, including experimental and clinical work focused on understanding the different roles of tonic and reflex sympathetic and vagal activity. The role of the baroreceptors, not just for the direct control of circulation but also because of the clinical value of interpreting alterations (spontaneous or induced) in their function, is discussed. The importance of the autonomic nervous system for gaining insights on risk stratification and for providing specific antiarrhythmic protection is also considered. Examples are the interventions to decrease sympathetic activity and/or to increase vagal activity. The non-invasive analysis of the RR and QT intervals provides additional information. The three of us have collaborated in several studies and each of us contributes with very specific and independent areas of expertise. Here, we have focused on those areas to which we have directly contributed and hence speak with personal experience. This is not an attempt to provide a neutral and general overview on the autonomic nervous system; rather, it represents our effort to share and provide the readers with our own personal views matured after many years of research in this field.
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Affiliation(s)
- Maria Teresa La Rovere
- Department of Cardiology, IRCCS Istituti Clinici Scientifici Maugeri, Montescano (Pavia), Italy
| | - Alberto Porta
- Department of Biomedical Sciences for Health, University of Milan, Milan, Italy.,Department of Cardiothoracic, Vascular Anesthesia and Intensive Care, IRCCS Policlinico San Donato, Milan, Italy
| | - Peter J Schwartz
- Center for Cardiac Arrhythmias of Genetic Origin and Laboratory of Cardiovascular Genetics, Istituto Auxologico Italiano, IRCCS, Milan, Italy
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Baumert M, Porta A, Vos MA, Malik M, Couderc JP, Laguna P, Piccirillo G, Smith GL, Tereshchenko LG, Volders PGA. QT interval variability in body surface ECG: measurement, physiological basis, and clinical value: position statement and consensus guidance endorsed by the European Heart Rhythm Association jointly with the ESC Working Group on Cardiac Cellular Electrophysiology. Europace 2016; 18:925-44. [PMID: 26823389 PMCID: PMC4905605 DOI: 10.1093/europace/euv405] [Citation(s) in RCA: 140] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2015] [Accepted: 11/05/2015] [Indexed: 12/20/2022] Open
Abstract
This consensus guideline discusses the electrocardiographic phenomenon of beat-to-beat QT interval variability (QTV) on surface electrocardiograms. The text covers measurement principles, physiological basis, and clinical value of QTV. Technical considerations include QT interval measurement and the relation between QTV and heart rate variability. Research frontiers of QTV include understanding of QTV physiology, systematic evaluation of the link between QTV and direct measures of neural activity, modelling of the QTV dependence on the variability of other physiological variables, distinction between QTV and general T wave shape variability, and assessing of the QTV utility for guiding therapy. Increased QTV appears to be a risk marker of arrhythmic and cardiovascular death. It remains to be established whether it can guide therapy alone or in combination with other risk factors. QT interval variability has a possible role in non-invasive assessment of tonic sympathetic activity.
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Affiliation(s)
- Mathias Baumert
- School of Electrical and Electronic Engineering, The University of Adelaide, Adelaide, SA, Australia
| | - Alberto Porta
- Department of Biomedical Sciences for Health, University of Milan, Milan, Italy Department of Cardiothoracic, Vascular Anesthesia and Intensive Care, IRCCS Policlinico San Donato, Milan, Italy
| | - Marc A Vos
- Department of Medical Physiology, Division of Heart and Lungs, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Marek Malik
- St Paul's Cardiac Electrophysiology, University of London, and National Heart and Lung Institute, Imperial College, Dovehouse Street, London SW3 6LY, UK
| | - Jean-Philippe Couderc
- Heart Research Follow-Up Program, University of Rochester Medical Center, Rochester, NY, USA
| | - Pablo Laguna
- Zaragoza University and CIBER-BBN, Zaragoza, Spain
| | - Gianfranco Piccirillo
- Dipartimento di Scienze Cardiovascolari, Respiratorie, Nefrologiche, Anestesiologiche e Geriatriche, Università 'La Sapienza' Rome, Rome, Italy
| | - Godfrey L Smith
- Institute of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow, UK
| | - Larisa G Tereshchenko
- Oregon Health and Science University, Knight Cardiovascular Institute, Portland, OR, USA
| | - Paul G A Volders
- Department of Cardiology, Cardiovascular Research Institute Maastricht, Maastricht University Medical Centre, Maastricht, The Netherlands
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Disturbances of cardiac wavelength and repolarization precede Torsade de Pointes and ventricular fibrillation in Langendorff perfused rabbit hearts. PROGRESS IN BIOPHYSICS AND MOLECULAR BIOLOGY 2016; 121:3-10. [DOI: 10.1016/j.pbiomolbio.2016.03.004] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/23/2016] [Revised: 03/04/2016] [Accepted: 03/10/2016] [Indexed: 11/20/2022]
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Seethala S, Singh P, Shusterman V, Ribe M, Haugaa KH, Němec J. QT Adaptation and Intrinsic QT Variability in Congenital Long QT Syndrome. J Am Heart Assoc 2015; 4:e002395. [PMID: 26675252 PMCID: PMC4845278 DOI: 10.1161/jaha.115.002395] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/01/2015] [Accepted: 11/03/2015] [Indexed: 01/08/2023]
Abstract
BACKGROUND Increased variability of QT interval (QTV) has been linked to arrhythmias in animal experiments and multiple clinical situations. Congenital long QT syndrome (LQTS), a pure repolarization disease, may provide important information on the relationship between delayed repolarization and QTV. METHODS AND RESULTS Twenty-four-hour Holter monitor tracings from 78 genotyped congenital LQTS patients (52 females; 51 LQT1, 23 LQT2, 2 LQT5, 2 JLN, 27 symptomatic; age, 35.2±12.3 years) were evaluated with computer-assisted annotation of RR and QT intervals. Several models of RR-QT relationship were tested in all patients. A model assuming exponential decrease of past RR interval contributions to QT duration with 60-second time constant provided the best data fit. This model was used to calculate QTc and residual "intrinsic" QTV, which cannot be explained by heart rate change. The intrinsic QTV was higher in patients with long QTc (r=0.68; P<10(-4)), and in LQT2 than in LQT1/5 patients (5.65±1.28 vs 4.46±0.82; P<0.0002). Both QTc and intrinsic QTV were similar in symptomatic and asymptomatic patients (467±52 vs 459±53 ms and 5.10±1.19 vs 4.74±1.09, respectively). CONCLUSIONS In LQTS patients, QT interval adaptation to heart rate changes occurs with time constant ≈60 seconds, similar to results reported in control subjects. Intrinsic QTV correlates with the degree of repolarization delay and might reflect action potential instability observed in animal models of LQTS.
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Affiliation(s)
- Srikanth Seethala
- Scripps ClinicSan DiegoCA
- Present address: University of TennesseeCollege of MedicineChattanoogaTN
| | | | | | - Margareth Ribe
- Department of CardiologyCenter for Cardiological Innovation and Institute for Surgical ResearchOslo University Hospital, RikshospitaletOsloNorway
| | - Kristina H. Haugaa
- Department of CardiologyCenter for Cardiological Innovation and Institute for Surgical ResearchOslo University Hospital, RikshospitaletOsloNorway
- University of OsloNorway
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Rahimi Darabad B, Vatandust J, Pourmousavi Khoshknab MM, Seyed Mohammad Zad MH. Survey of the effect of streptokinase on ventricular repolarization by examining the QT dispersion in patients with acute myocardial infraction in Seyed-Al-Shohada hospital, Urmia. Glob J Health Sci 2014; 6:74-82. [PMID: 25363182 PMCID: PMC4796378 DOI: 10.5539/gjhs.v6n7p74] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2014] [Revised: 08/11/2014] [Accepted: 07/28/2014] [Indexed: 11/25/2022] Open
Abstract
Cardiovascular events are the most common cause of morbidity and mortality throughout the world and myocardial infarction is the most common cause of these accidents. Myocardial infarction impairs the mechanical and electrical activity of the heart that these disorders predispose the patient to cardiac arrhythmias including ventricular tachycardia. QT dispersion is an important parameter to evaluate the heterogeneity of ventricular repolarization that minimal and the maximum interval is QTc in 12-lead EKG. In this study, 200 patients with the diagnosis of acute myocardial infraction with ST-segment elevation were hospitalized and treated with streptokinase. Patient records were extracted from the medical records department. EKG was studied before receiving streptokinase, an hour after receiving streptokinase and 4 days later for calculating and comparing QTd. It was concluded that QTd mean in EKG one hour after receiving streptokinase is decreased compared to pre-operation but this decline is not statistically significant. QTd mean in EKG day 4 after MI is slightly increased compared to the baseline, which is not statistically significant.
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Lux RL, Sower CT, Allen N, Etheridge SP, Tristani-Firouzi M, Saarel EV. The application of root mean square electrocardiography (RMS ECG) for the detection of acquired and congenital long QT syndrome. PLoS One 2014; 9:e85689. [PMID: 24454918 PMCID: PMC3893255 DOI: 10.1371/journal.pone.0085689] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2013] [Accepted: 12/05/2013] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Precise measurement of the QT interval is often hampered by difficulty determining the end of the low amplitude T wave. Root mean square electrocardiography (RMS ECG) provides a novel alternative measure of ventricular repolarization. Experimental data have shown that the interval between the RMS ECG QRS and T wave peaks (RTPK) closely reflects the mean ventricular action potential duration while the RMS T wave width (TW) tracks the dispersion of repolarization timing. Here, we tested the precision of RMS ECG to assess ventricular repolarization in humans in the setting of drug-induced and congenital Long QT Syndrome (LQTS). METHODS RMS ECG signals were derived from high-resolution 24 hour Holter monitor recordings from 68 subjects after receiving placebo and moxifloxacin and from standard 12 lead ECGs obtained in 97 subjects with LQTS and 97 age- and sex-matched controls. RTPK, QTRMS and RMS TW intervals were automatically measured using custom software and compared to traditional QT measures using lead II. RESULTS All measures of repolarization were prolonged during moxifloxacin administration and in LQTS subjects, but the variance of RMS intervals was significantly smaller than traditional lead II measurements. TW was prolonged during moxifloxacin and in subjects with LQT-2, but not LQT-1 or LQT-3. CONCLUSION These data validate the application of RMS ECG for the detection of drug-induced and congenital LQTS. RMS ECG measurements are more precise than the current standard of care lead II measurements.
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Affiliation(s)
- Robert L. Lux
- Nora Eccles Harrison Cardiovascular Research and Training Institute, University of Utah, Salt Lake City, Utah, United States of America
| | - Christopher Todd Sower
- Nora Eccles Harrison Cardiovascular Research and Training Institute, University of Utah, Salt Lake City, Utah, United States of America
| | - Nancy Allen
- Nora Eccles Harrison Cardiovascular Research and Training Institute, University of Utah, Salt Lake City, Utah, United States of America
| | - Susan P. Etheridge
- The Division of Pediatric Cardiology, University of Utah, Salt Lake City, Utah, United States of America
| | - Martin Tristani-Firouzi
- Nora Eccles Harrison Cardiovascular Research and Training Institute, University of Utah, Salt Lake City, Utah, United States of America
- The Division of Pediatric Cardiology, University of Utah, Salt Lake City, Utah, United States of America
- * E-mail:
| | - Elizabeth V. Saarel
- The Division of Pediatric Cardiology, University of Utah, Salt Lake City, Utah, United States of America
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Akoum NW, Wasmund SL, Lux RL, Hamdan MH. Reverse electrical remodeling of the ventricles following successful restoration of sinus rhythm in patients with persistent atrial fibrillation. PACING AND CLINICAL ELECTROPHYSIOLOGY: PACE 2011; 33:1198-202. [PMID: 20487353 DOI: 10.1111/j.1540-8159.2010.02788.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
BACKGROUND Atrial fibrillation (AF) has been shown to be associated with reduced survival and increased ventricular arrhythmogenesis. The purpose of this study was to assess the effects of AF with adequate rate control on the electrophysiologic properties of the ventricles. We hypothesized that AF results in increased ventricular arrhythmogenic risk and that reverse remodeling occurs post-successful cardioversion. METHODS In nine patients with persistent AF, we recorded 12-lead electrocardiograms (ECGs) and 1-hour high-resolution Holter ECGs (H12+, Mortara Instrument, Inc. Milwaukee, WI, USA; recorders [1000 sps] immediately following cardioversion (Day 1) and after 30 days of maintaining sinus rhythm (Day 30). We measured QTc, QT dispersion, and calculated estimates of mean ventricular action potential duration (RT), diastolic interval (DI), T-wave width (TW), T-wave peak-to-end, and their respective scatter on Day 1 and Day 30. Maintenance of normal sinus rhythm was confirmed with a weekly trans-telephonic ECG transmission. RESULTS The average QTc interval decreased from 449 ± 28 ms on Day 1 to 422 ± 36 ms on Day 30 (P = 0.04). There was no significant difference in the average QT dispersion. A significant decrease was also noted in DI and TW scatter at Day 30 when compared with Day 1 (P = 0.03 and 0.04, respectively). A decrease in RT scatter was also noted albeit not statistically significant (P = 0.07). CONCLUSION Our results suggest a greater propensity to ventricular arrhythmogenesis in the immediate period following restoration of sinus rhythm and reverse electrical remodeling of the ventricles during the first month after successful maintenance of sinus rhythm. (PACE 2010; 33:1198-1202).
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Affiliation(s)
- Nazem W Akoum
- Division of Cardiology, University of Utah and Nora Eccles Harrison Cardiovascular Research and Training Institute, Salt Lake City, UT 84132, USA
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Tereshchenko LG, Han L, Cheng A, Marine JE, Spragg DD, Sinha S, Dalal D, Calkins H, Tomaselli GF, Berger RD. Beat-to-beat three-dimensional ECG variability predicts ventricular arrhythmia in ICD recipients. Heart Rhythm 2010; 7:1606-13. [PMID: 20816873 DOI: 10.1016/j.hrthm.2010.08.022] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/25/2010] [Accepted: 08/29/2010] [Indexed: 10/19/2022]
Abstract
BACKGROUND Methodological difficulties associated with QT measurements prompt the search for new electrocardiographic markers of repolarization heterogeneity. OBJECTIVE We hypothesized that beat-to-beat 3-dimensional vectorcardiogram variability predicts ventricular arrhythmia (VA) in patients with structural heart disease, left ventricular systolic dysfunction, and implanted implantable cardioverter-defibrillators (ICDs). METHODS Baseline orthogonal electrocardiograms were recorded in 414 patients with structural heart disease (mean age 59.4 ± 12.0; 280 white [68%] and 134 black [32%]) at rest before implantation of ICD for primary prevention of sudden cardiac death. R and T peaks of 30 consecutive sinus beats were plotted in 3 dimensions to form an R peaks cloud and a T peaks cloud. The volume of the peaks cloud was calculated as the volume within the convex hull. Patients were followed up for at least 6 months; sustained VA with appropriate ICD therapies served as an end point. RESULTS During a mean follow-up time of 18.4 ± 12.5 months, 61 of the 414 patients (14.73% or 9.6% per person-year of follow-up) experienced sustained VA with appropriate ICD therapies: 41 of them were white and 20 were black. In the multivariate Cox model that included inducibility of VA and use of beta-blockers, the highest tertile of T/R peaks cloud volume ratio significantly predicted VA (hazard ratio 1.68, 95% confidence interval 1.01 to 2.80; P = .046) in all patients. T peaks cloud volume and T/R peaks cloud volume ratio were significantly smaller in black subjects (median 0.09 [interquartile range 0.04 to 0.15] vs. median 0.11 [interquartile range 0.06 to 0.22], P = .002). CONCLUSION A relatively large T peaks cloud volume is associated with increased risk of VA in patients with structural heart disease and systolic dysfunction.
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Affiliation(s)
- Larisa G Tereshchenko
- Division of Cardiology, Department of Medicine, Johns Hopkins Hospital, Baltimore, Maryland, USA.
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Porta A, Tobaldini E, Gnecchi-Ruscone T, Montano N. RT variability unrelated to heart period and respiration progressively increases during graded head-up tilt. Am J Physiol Heart Circ Physiol 2010; 298:H1406-14. [PMID: 20154259 DOI: 10.1152/ajpheart.01206.2009] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Open-loop linear parametric models were exploited to describe ventricular repolarization duration (VRD) variability during graded head-up tilt. Surface ECG and thoracic movements were recorded in 15 healthy humans (age: 24-54 yr, median: 28 yr; 6 women and 9 men). Tilt table inclinations ranged from 15 to 90 degrees and were varied in steps of 15 degrees . All subjects underwent recordings at every step in random order. Heart period was assessed as the time difference between two consecutive R-wave peaks (RR) and the respiratory signal (R) as the sampling of the thoracic movement signal at the R-wave peaks. VRD was measured automatically as the temporal difference between the R-wave peak and T-wave apex (RT(a)) or T-wave end (RT(e)). The best model decomposed RT variability as due to RR changes (RR-related RT variability) to direct respiratory-related inputs (R-related RT variability) and to unknown rhythmical sources unrelated to RR changes and R (RR-R-unrelated RT variability). Using this model, RT(e) variability was found to be less predictable than RT(a) variability and composed of a smaller fraction of RR-related RT variability and a larger fraction of RR-R-unrelated RT variability. Predictability progressively decreased with tilt table angles, suggesting increased complexity of RT regulation. RT variance progressively increased with tilt table inclination. This increase was characterized by a gradual rise of the amount of RR-R-unrelated RT variability, whereas the amount of RR-related RT variability remained unchanged. These results suggest that the amount of RT variability, complexity of RT dynamics, and amount of RR-R-unrelated RT variability increase with the magnitude of the sympathetic drive directly related to tilt table inclination. We propose the utilization of the amount of RR-R-unrelated RT variability instead of overall RT variability as an indirect measure of autonomic regulation directed to ventricles.
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Affiliation(s)
- Alberto Porta
- Università degli Studi di Milano, Dipartimento di Tecnologie per la Salute, Istituto Ortopedico Galeazzi, Laboratorio di Modellistica di Sistemi Complessi, Via R. Galeazzi 4, Milan, Italy.
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Nemec J, Buncová M, Shusterman V, Winter B, Shen WK, Ackerman MJ. QT interval variability and adaptation to heart rate changes in patients with long QT syndrome. PACING AND CLINICAL ELECTROPHYSIOLOGY: PACE 2009; 32:72-81. [PMID: 19140916 DOI: 10.1111/j.1540-8159.2009.02179.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
BACKGROUND Increased QT variability (QTV) has been reported in conditions associated with ventricular arrhythmias. Data on QTV in patients with congenital long QT syndrome (LQTS) are limited. METHODS Ambulatory electrocardiogram recordings were analyzed in 23 genotyped LQTS patients and in 16 healthy subjects (C). Short-term QTV was compared between C and LQTS. The dependence of QT duration on heart rate was evaluated with three different linear models, based either on the RR interval preceding the QT interval (RR(0)), the RR interval preceding RR(0) (RR(-1)), or the average RR interval in the 60-second period before QT interval (mRR). RESULTS Short-term QTV was significantly higher in LQTS than in C subjects (14.94 +/- 9.33 vs 7.31 +/- 1.29 ms; P < 0.001). It was also higher in the non-LQT1 than in LQT1 patients (23.00 +/- 9.05 vs 8.74 +/- 1.56 ms; P < 0.001) and correlated positively with QTc in LQTS (r = 0.623, P < 0.002). In the C subjects, the linear model based on mRR predicted QT duration significantly better than models based on RR(0) and RR(-1). It also provided better fit than any nonlinear model based on RR(0). This was also true for LQT1 patients. For non-LQT1 patients, all models provided poor prediction of QT interval. CONCLUSIONS QTV is elevated in LQTS patients and is correlated with QTc in LQTS. Significant differences with respect to QTV exist among different genotypes. QT interval duration is strongly affected by noninstantaneous heart rate in both C and LQT1 subjects. These findings could improve formulas for QT interval correction and provide insight on cellular mechanisms of QT adaptation.
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Affiliation(s)
- Jan Nemec
- Cardiovascular Institute, University of Pittsburgh, Pittsburgh, Pennsylvania 15213, USA.
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Korhonen P, Husa T, Konttila T, Tierala I, Mäkijärvi M, Väänänen H, Toivonen L. Complex T-wave morphology in body surface potential mapping in prediction of arrhythmic events in patients with acute myocardial infarction and cardiac dysfunction. Europace 2009; 11:514-20. [PMID: 19279023 DOI: 10.1093/europace/eup051] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
AIMS Heterogeneous ventricular repolarization is associated with sudden cardiac death after myocardial infarction (MI). This prospective study investigated repolarization disparity with parameters based on T-wave morphology in body surface potential mapping (BSPM) in the assessment of arrhythmia risk in patients with a recent MI and cardiac dysfunction. METHODS AND RESULTS Patients (n = 158) had 120-lead BSPM and 12-lead electrocardiogram (ECG) registered soon after acute MI. Principal component analysis (PCA) of the T-wave and T-wave vector loop descriptors were applied to compute parameters describing T-wave morphology and its variation. The study endpoints were arrhythmic events and all-cause mortality. During a mean follow-up of 50 months, 30 patients (19%) died and 16 (10%) had an arrhythmic event. Most of the parameters differed significantly between patients with and without arrhythmic events. In univariate analysis, T-wave vector loop length (TLL) and PCA parameter PCA(3) in BSPM and TLL in ECG were significant predictors of arrhythmic events. In multivariate analysis including several clinical variables, these parameters also showed an independent prediction, with parameters in BSPM performing somewhat better. None of the parameters predicted all-cause mortality. CONCLUSION Complex T-wave morphology in BSPM is a marker of arrhythmia propensity in patients with a recent MI and cardiac dysfunction.
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Affiliation(s)
- Petri Korhonen
- Division of Cardiology, Helsinki University Hospital, PL 340, 00029 HUS Helsinki, Finland.
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