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Gilchrist RJ. Cardiac memory: a phenomenon with important clinical implications. Nat Rev Cardiol 2024; 21:282. [PMID: 38454168 DOI: 10.1038/s41569-024-01008-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 03/09/2024]
Affiliation(s)
- Rebecca J Gilchrist
- School of Cardiovascular and Metabolic Health, University of Glasgow, Glasgow, UK.
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2
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Elizari MV, Aguinaga L. Argentina's most important contributions in the field of electrophysiology. Heart Rhythm O2 2024; 5:3-7. [PMID: 38312206 PMCID: PMC10837184 DOI: 10.1016/j.hroo.2023.10.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2024] Open
Abstract
Latin American electrocardiology emerged internationally thanks to the Argentine School of Electrocardiology. All started when the idea of a different anatomy of the conduction system was not only necessary to change the paradigm of a bifascicular system, but also to question diagnostic electrocardiographic criteria adopted by the scientific community without dispute. Almost every scientific contribution coming from the Argentine School of Electrocardiology represented a significant step forward in the understanding of the electrophysiology of the heart and its electrocardiographic counterpart. There is another reason that increases their value: the noticeable simplicity of the technical facilities with which these studies were done from the modest laboratory in Argentina, whose production was purely and genuinely Latin American. In the following lines we summarize what we consider to be the greatest contributions of the Argentine school to world electrophysiology.
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Affiliation(s)
| | - Luis Aguinaga
- Centro Integral de Arritmias Tucumán, Tucumán, Argentina
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3
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Dural M, Ghossein MA, Gerrits W, Daniels F, Meine M, Maass AH, Rienstra M, Prinzen FW, Vernooy K, van Stipdonk AMW. Association of vectorcardiographic T-wave area with clinical and echocardiographic outcomes in cardiac resynchronization therapy. Europace 2023; 26:euad370. [PMID: 38146837 PMCID: PMC10766142 DOI: 10.1093/europace/euad370] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2023] [Accepted: 12/19/2023] [Indexed: 12/27/2023] Open
Abstract
AIMS Data on repolarization parameters in cardiac resynchronization therapy (CRT) are scarce. We investigated the association of baseline T-wave area, with both clinical and echocardiographic outcomes of CRT in a large, multi-centre cohort of CRT recipients. Also, we evaluated the association between the baseline T-wave area and QRS area. METHODS AND RESULTS In this retrospective study, 1355 consecutive CRT recipients were evaluated. Pre-implantation T-wave and QRS area were calculated from vectorcardiograms. Echocardiographic response was defined as a reduction of ≥15% in left ventricular end-systolic volume between 3 and 12 months after implantation. The clinical outcome was a combination of all-cause mortality, heart transplantation, and left ventricular assist device implantation. Left ventricular end-systolic volume reduction was largest in patients with QRS area ≥ 109 μVs and T-wave area ≥ 66 μVs compared with QRS area ≥ 109 μVs and T-wave area < 66 μVs (P = 0.004), QRS area < 109 μVs and T-wave area ≥ 66 μVs (P < 0.001) and QRS area < 109 μVs and T-wave area < 66 μVs (P < 0.001). Event-free survival rate was higher in the subgroup of patients with QRS area ≥ 109 μVs and T-wave area ≥ 66 μVs (n = 616, P < 0.001) and QRS area ≥ 109 μVs and T-wave area < 66 μVs (n = 100, P < 0.001) than the other subgroups. In the multivariate analysis, T-wave area remained associated with echocardiographic response (P = 0.008), but not with the clinical outcome (P = 0.143), when QRS area was included in the model. CONCLUSION Baseline T-wave area has a significant association with both clinical and echocardiographic outcomes after CRT. The association of T-wave area with echocardiographic response is independent from QRS area; the association with clinical outcome, however, is not.
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Affiliation(s)
- Muhammet Dural
- Department of Cardiology, Eskişehir Osmangazi University Faculty of Medicine, Odunpazarı, Eskişehir 26040, Turkey
- Department of Cardiology, Cardiovascular Research Institute Maastricht (CARIM), Maastricht University Medical Centre+, Maastricht 6202, The Netherlands
| | - Mohammed A Ghossein
- Department of Physiology, Cardiovascular Research Institute Maastricht (CARIM), Maastricht University, Maastricht, The Netherlands
| | - Willem Gerrits
- Department of Cardiology, University Medical Centre Utrecht, Utrecht, The Netherlands
| | - Fenna Daniels
- Department of Cardiology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Mathias Meine
- Department of Cardiology, University Medical Centre Utrecht, Utrecht, The Netherlands
| | - Alexander H Maass
- Department of Cardiology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Michiel Rienstra
- Department of Cardiology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Frits W Prinzen
- Department of Physiology, Cardiovascular Research Institute Maastricht (CARIM), Maastricht University, Maastricht, The Netherlands
| | - Kevin Vernooy
- Department of Cardiology, Cardiovascular Research Institute Maastricht (CARIM), Maastricht University Medical Centre+, Maastricht 6202, The Netherlands
| | - Antonius M W van Stipdonk
- Department of Cardiology, Cardiovascular Research Institute Maastricht (CARIM), Maastricht University Medical Centre+, Maastricht 6202, The Netherlands
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4
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Malik M, Farooqi MS, Karim R, Khan S, Rind IA. Memory T-Waves: An Uncharted Territory in T-Wave Inversions. Cureus 2023; 15:e47620. [PMID: 38022234 PMCID: PMC10667626 DOI: 10.7759/cureus.47620] [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] [Accepted: 10/25/2023] [Indexed: 12/01/2023] Open
Abstract
T-wave inversions on electrocardiograms (ECGs) can present a diagnostic challenge due to their association with various underlying causes. One less-explored cause is memory T-waves, a phenomenon characterized by T-wave inversions, often seen in chest and inferior leads, following a period of abnormal ventricular conduction. In this case report, we discuss the intriguing case of an 80-year-old woman who recently underwent percutaneous coronary intervention (PCI) for a myocardial infarction and subsequently developed memory T-waves. We are also discussing how important it can be to understand and recognize memory T-waves, as it will avoid further unnecessary tests and longer hospital stays.
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Affiliation(s)
- Munzir Malik
- Acute Medicine, Wrexham Maelor Hospital, Wrexham, GBR
| | | | | | - Saleem Khan
- Medicine, Betsi Cadwaladr University Health Board, Wrexham, GBR
| | - Irfan Ali Rind
- Cardiology, Betsi Cadwaladr University Health Board, Wrexham, GBR
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5
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Naik R, Thyagaturu H, Awad M, Bischof E. The Heart Remembers: A Case of Cardiac Memory. Cureus 2023; 15:e42106. [PMID: 37602025 PMCID: PMC10436023 DOI: 10.7759/cureus.42106] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/18/2023] [Indexed: 08/22/2023] Open
Abstract
An 80-year-old male with a history of atrial fibrillation and a single-chamber ventricular pacemaker presented to the hospital for an elective colonoscopy. He experienced a transient episode of unresponsiveness with seizure-like activity before the procedure. This prompted him to get an EKG showing deep T-wave inversions (TWIs) in the precordial leads on a background of paced beats. Such findings were concerning for an acute and potentially life-threatening process such as myocardial infarction (MI) or intracranial insult. After ruling out any severe conditions, the EKG findings were attributed to cardiac memory, an underdiagnosed cause of deep TWIs in patients with a pacemaker.
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Affiliation(s)
- Riddhima Naik
- Internal Medicine, Bassett Healthcare Network, Cooperstown, USA
| | | | - Maan Awad
- Internal Medicine, West Virginia University School of Medicine, Morgantown, USA
| | - Edward Bischof
- Internal Medicine, Bassett Healthcare Network, Cooperstown, USA
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6
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Abstract
Cardiac memory is the term used to describe an interesting electrocardiographic phenomenon. Whenever a QRS complex is wide and abnormal, such as during ventricular pacing, the T waves will also be abnormal and will point to the opposite direction of the wide QRS. If the QRS then normalizes, such as after cessation of ventricular pacing, the T waves will normalize as well, but at a later stage. The period of cardiac memory is the phase between the sudden normalization of the QRS and the eventual and gradual return of the T waves to their baseline morphology. Cardiac memory is assumed to be an innocent electrocardiographic curiosity. However, during cardiac memory, reduction of repolarizing potassium currents increases left ventricular repolarization gradients. Therefore, when cardiac memory occurs in patients who already have a prolonged QT interval (for whatever reason), it can lead to a frank long QT syndrome with QT-related ventricular arrhythmias (torsades de pointes). These arrhythmogenic effects of cardiac memory are not generally appreciated and are reviewed here for the first time.
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Affiliation(s)
- Sami Viskin
- Department of Cardiology, Tel Aviv Sourasky Medical Center and Sackler School of Medicine, Tel Aviv University, Israel (S.V., E.C., A.L.S., R.R.)
| | - Ehud Chorin
- Department of Cardiology, Tel Aviv Sourasky Medical Center and Sackler School of Medicine, Tel Aviv University, Israel (S.V., E.C., A.L.S., R.R.)
| | - Arie Lorin Schwartz
- Department of Cardiology, Tel Aviv Sourasky Medical Center and Sackler School of Medicine, Tel Aviv University, Israel (S.V., E.C., A.L.S., R.R.)
| | - Piotr Kukla
- Department of Internal Medicine and Cardiology, Specialistic Hospital, Gorlice, Poland (P.K.)
| | - Raphael Rosso
- Department of Cardiology, Tel Aviv Sourasky Medical Center and Sackler School of Medicine, Tel Aviv University, Israel (S.V., E.C., A.L.S., R.R.)
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7
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Verzaal NJ, van Deursen CJM, Pezzuto S, Wecke L, van Everdingen WM, Vernooy K, Delhaas T, Auricchio A, Prinzen FW. Synchronization of repolarization after cardiac resynchronization therapy: a combined clinical and modeling study. J Cardiovasc Electrophysiol 2022; 33:1837-1846. [PMID: 35662306 PMCID: PMC9539692 DOI: 10.1111/jce.15581] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/08/2022] [Revised: 05/27/2022] [Accepted: 05/30/2022] [Indexed: 11/29/2022]
Abstract
Introduction The changes in ventricular repolarization after cardiac resynchronization therapy (CRT) are poorly understood. This knowledge gap is addressed using a multimodality approach including electrocardiographic and echocardiographic measurements in patients and using patient‐specific computational modeling. Methods In 33 patients electrocardiographic and echocardiographic measurements were performed before and at various intervals after CRT, both during CRT‐ON and temporary CRT‐OFF. T‐wave area was calculated from vectorcardiograms, and reconstructed from the 12‐lead electrocardiography (ECG). Computer simulations were performed using a patient‐specific eikonal model of cardiac activation with spatially varying action potential duration (APD) and repolarization rate, fit to a patient's ECG. Results During CRT‐ON T‐wave area diminished within a day and remained stable thereafter, whereas QT‐interval did not change significantly. During CRT‐OFF T‐wave area doubled within 5 days of CRT, while QT‐interval and peak‐to‐end T‐wave interval hardly changed. Left ventricular (LV) ejection fraction only increased significantly increased after 1 month of CRT. Computer simulations indicated that the increase in T‐wave area during CRT‐OFF can be explained by changes in APD following chronic CRT that are opposite to the change in CRT‐induced activation time. These APD changes were associated with a reduction in LV dispersion in repolarization during chronic CRT. Conclusion T‐wave area during CRT‐OFF is a sensitive marker for adaptations in ventricular repolarization during chronic CRT that may include a reduction in LV dispersion of repolarization.
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Affiliation(s)
- Nienke J Verzaal
- Department of Physiology, Cardiovascular Research Institute Maastricht, Maastricht University, P.O. Box 616, 6200 MD, Maastricht, the Netherlands
| | - Caroline J M van Deursen
- Department of Cardiology, Maastricht University Medical Center, P.O. Box 5800, 6202 AZ, Maastricht, The Netherlands
| | - Simone Pezzuto
- Center for Computational Medicine in Cardiology, Euler Institute, Università della Svizzera Italiana, via via Buffi 13, 6900, Lugano, Switzerland
| | - Liliane Wecke
- Heart Clinic, Capio St. Göran's Hospital, Sankt Göransplan 1, 11281, Stockholm, Sweden
| | | | - Kevin Vernooy
- Department of Cardiology, Maastricht University Medical Center, P.O. Box 5800, 6202 AZ, Maastricht, The Netherlands
| | - Tammo Delhaas
- Department of Biomedical Engineering, Maastricht University, P.O. Box 616, 6200 MD, Maastricht, the Netherlands
| | - Angelo Auricchio
- Center for Computational Medicine in Cardiology, Euler Institute, Università della Svizzera Italiana, via via Buffi 13, 6900, Lugano, Switzerland.,Department of Cardiology, Istituto Cardiocentro Ticino, Lugano, Switzerland
| | - Frits W Prinzen
- Department of Physiology, Cardiovascular Research Institute Maastricht, Maastricht University, P.O. Box 616, 6200 MD, Maastricht, the Netherlands
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8
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Austin KM, Alexander ME, Triedman JK. Pediatric T-wave memory after accessory pathway ablation in Wolff-Parkinson-White syndrome. Heart Rhythm 2022; 19:459-465. [PMID: 34767987 PMCID: PMC9026902 DOI: 10.1016/j.hrthm.2021.11.007] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/16/2021] [Revised: 10/20/2021] [Accepted: 11/03/2021] [Indexed: 11/19/2022]
Abstract
BACKGROUND Altered ventricular depolarization due to manifest accessory pathway conduction (ie, Wolff-Parkinson-White syndrome) leads to repolarization abnormalities that persist after pathway ablation. The term T-wave memory (TWM) has been applied to these changes, as the postablation T-wave vector "remembers" the pre-excited QRS vector. In adults, these abnormalities can be misinterpreted as ischemia leading to unnecessary interventions. To date, no comprehensive studies have evaluated this phenomenon in the pediatric population. OBJECTIVE The purpose of this study was to define TWM in the pediatric population, identify preablation risk factors, and delineate the timeline of recovery. METHODS Pre- and postablation electrocardiograms (ECGs) in patients ≤25 years were analyzed over a 5-year period. Frontal plane QTc interval, T-wave axis, QRST angle, and T-wave inversions were used to identify patients with TWM. Univariate analysis was performed to determine the association of preablation ECG features with the outcome of TWM. RESULTS TWM was present in 42% of pediatric patients, with resolution occurring within 3 months of ablation. Preablation QRS axis <0° was a strong predictor of TWM (odds ratio [OR] 15.2; 95% confidence interval [CI] 5.7-40), followed by posteroseptal pathway location (right posteroseptal-OR 8.9; 95% CI 4.2-18.8; left posteroseptal-OR 6.1; 95% CI 1.7-22.3). The degree of pre-excitation had a modest association with the development of TWM. No adverse events were observed. CONCLUSION TWM is less common in children compared to adults, and normalization occurred within 3 months postablation. The most predictive features for the development of TWM include a leftward pre-excited QRS axis and posteroseptal pathway location.
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Affiliation(s)
- Karyn M Austin
- Arrhythmia Service, Department of Cardiology, Boston Children's Hospital, Boston, Massachusetts; Department of Pediatrics, Harvard Medical School, Boston, Massachusetts.
| | - Mark E Alexander
- Arrhythmia Service, Department of Cardiology, Boston Children's Hospital, Boston, Massachusetts; Department of Pediatrics, Harvard Medical School, Boston, Massachusetts
| | - John K Triedman
- Arrhythmia Service, Department of Cardiology, Boston Children's Hospital, Boston, Massachusetts; Department of Pediatrics, Harvard Medical School, Boston, Massachusetts
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9
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Fang S. Pseudo-Wellens’ syndrome secondary to postexercise syncope. World J Emerg Med 2022; 13:334-336. [DOI: 10.5847/wjem.j.1920-8642.2022.064] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Accepted: 02/07/2022] [Indexed: 11/19/2022] Open
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10
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Zheng R, Wu S, Wang S, Su L, Ellenbogen KA, Huang W. Case Report: Interventricular Septal Hematoma Complicating Left Bundle Branch Pacing Lead Implantation. Front Cardiovasc Med 2021; 8:744079. [PMID: 34651029 PMCID: PMC8505742 DOI: 10.3389/fcvm.2021.744079] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2021] [Accepted: 09/07/2021] [Indexed: 11/17/2022] Open
Abstract
Background: Left bundle branch pacing (LBBP) is a novel physiological pacing and previous studies have confirmed the feasibility and safety of it. The incidence of complications in LBBP is relatively low as reported. Here we present a case of interventricular septal hematoma complicating LBBP lead implantation. Case summary: LBBP was achieved for treatment of high-grade atrioventricular block in a 67-year-old female. Chest pain began 1 h after implantation when the electrocardiogram showed ST-T changes. Then bedside echocardiography confirmed the formation of interventricular septal hematoma. Urgent coronary angiography showed the contrast agent retention and overflow in the interventricular septum. The symptom was relieved half an hour later. Echocardiogram performed 2 h later revealed the size of the hematoma was the same as before. The electrocardiography, coronary angiography and CTA confirmed the resolution of the hematoma at 1-month follow-up. Pacing parameters and cardiac function remained stable during 6-month follow-up. Conclusion: This is the first reported case describing the clinic features and management of interventricular septum hematoma complicating LBBP. The importance of routine echocardiograms after implantation for identifying the hematoma should be highlighted.
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Affiliation(s)
- Rujie Zheng
- Department of Cardiology, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, China.,The Key Lab of Cardiovascular Disease, Science and Technology of Wenzhou, Wenzhou, China
| | - Shengjie Wu
- Department of Cardiology, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, China.,The Key Lab of Cardiovascular Disease, Science and Technology of Wenzhou, Wenzhou, China
| | - Songjie Wang
- Department of Cardiology, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, China.,The Key Lab of Cardiovascular Disease, Science and Technology of Wenzhou, Wenzhou, China
| | - Lan Su
- Department of Cardiology, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, China.,The Key Lab of Cardiovascular Disease, Science and Technology of Wenzhou, Wenzhou, China
| | | | - Weijian Huang
- Department of Cardiology, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, China.,The Key Lab of Cardiovascular Disease, Science and Technology of Wenzhou, Wenzhou, China
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11
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Tóth N, Szlovák J, Kohajda Z, Bitay G, Veress R, Horváth B, Papp JG, Varró A, Nagy N. The development of L-type Ca 2+ current mediated alternans does not depend on the restitution slope in canine ventricular myocardium. Sci Rep 2021; 11:16652. [PMID: 34404848 PMCID: PMC8371021 DOI: 10.1038/s41598-021-95299-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2021] [Accepted: 07/23/2021] [Indexed: 11/25/2022] Open
Abstract
Cardiac alternans have crucial importance in the onset of ventricular fibrillation. The early explanation for alternans development was the voltage-driven mechanism, where the action potential (AP) restitution steepness was considered as crucial determining factor. Recent results suggest that restitution slope is an inadequate predictor for alternans development, but several studies still claim the role of membrane potential as underlying mechanism of alternans. These controversial data indicate that the relationship of restitution and alternans development is not completely understood. APs were measured by conventional microelectrode technique from canine right ventricular papillary muscles. Ionic currents combined with fluorescent measurements were recorded by patch-clamp technique. APs combined with fluorescent measurements were monitored by sharp microelectrodes. Rapid pacing evoked restitution-independent AP duration (APD) alternans. When non-alternating AP voltage command was used, Ca2+i-transient (CaT) alternans were not observed. When alternating rectangular voltage pulses were applied, CaT alternans were proportional to ICaL amplitude alternans. Selective ICaL inhibition did not influence the fast phase of APD restitution. In this study we found that ICaL has minor contribution in shaping the fast phase of restitution curve suggesting that ICaL—if it plays important role in the alternans mechanism—could be an additional factor that attenuates the reliability of APD restitution slope to predict alternans.
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Affiliation(s)
- Noémi Tóth
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Dóm tér 12, P.O. Box 427, 6720, Szeged, Hungary
| | - Jozefina Szlovák
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Dóm tér 12, P.O. Box 427, 6720, Szeged, Hungary
| | - Zsófia Kohajda
- ELKH-SZTE Research Group of Cardiovascular Pharmacology, Szeged, Hungary
| | - Gergő Bitay
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Dóm tér 12, P.O. Box 427, 6720, Szeged, Hungary
| | - Roland Veress
- Department of Physiology, Faculty of Medicine, University of Debrecen, Debrecen, Hungary
| | - Balázs Horváth
- Department of Physiology, Faculty of Medicine, University of Debrecen, Debrecen, Hungary.,Faculty of Pharmacy, University of Debrecen, Debrecen, Hungary
| | - Julius Gy Papp
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Dóm tér 12, P.O. Box 427, 6720, Szeged, Hungary.,ELKH-SZTE Research Group of Cardiovascular Pharmacology, Szeged, Hungary
| | - András Varró
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Dóm tér 12, P.O. Box 427, 6720, Szeged, Hungary.,ELKH-SZTE Research Group of Cardiovascular Pharmacology, Szeged, Hungary.,Department of Pharmacology and Pharmacotherapy, Interdisciplinary Excellence Centre, University of Szeged, Szeged, Hungary
| | - Norbert Nagy
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Dóm tér 12, P.O. Box 427, 6720, Szeged, Hungary. .,ELKH-SZTE Research Group of Cardiovascular Pharmacology, Szeged, Hungary.
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12
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Ballet A, Mulleman R, Vandermotte M. The heart remembers what the mind forgets. Acta Clin Belg 2021; 76:310-313. [PMID: 31996105 DOI: 10.1080/17843286.2020.1724449] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Background: Cardiac memory, also known as the Chatterjee phenomenon, is a poorly understood, under-recognized but important and benign cause of T-wave inversions. After a period of abnormal ventricular activation, such as ventricular pacing, intermittent left bundle branch block or pre-excitation, the heart 'remembers' and mirrors its repolarization in the direction of the previous QRS. It usually manifests as T-wave inversions that can linger up to weeks after the provocative event.Case summary: An 87-year-old man with extensive cardiovascular history and risk factors presented to the emergency department with shortness of breath and chest pain. An ECG taken on admission revealed deep widespread T wave inversions. Serial high sensitive cardiac troponin (hs-cTn) however remained negative (<10 ng/ml) with a negative D-dimer. Upon reviewing previous ECGs and the medical history, the patient was diagnosed with cardiac memory, which required no further treatment.Conclusion: Cardiac memory should be considered in any patient with a ventricular pacemaker that presents with narrow QRS rhythm and T-wave changes suggestive of ischemia. Although it remains a diagnosis of exclusion, recognizing this important clinical entity can prevent unnecessary admissions, expensive diagnostic tests and invasive procedures.
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Affiliation(s)
- Arne Ballet
- Faculty of Medicine and Health Sciences, University of Antwerp, Antwerp, Belgium
| | - Ritchie Mulleman
- Faculty of Medicine and Health Sciences, University of Antwerp, Antwerp, Belgium
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13
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Gunaseelan R, Sasikumar M, Aswin K, Nithya B, Balamurugan N, Vivekanandan M. Memory T-Waves, a Rare Cause of T-Wave Inversion in the Emergency Department. J Emerg Trauma Shock 2021; 13:312-316. [PMID: 33897151 PMCID: PMC8047955 DOI: 10.4103/jets.jets_70_20] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2020] [Accepted: 08/22/2020] [Indexed: 12/02/2022] Open
Abstract
One of the rare causes of diffuse T-wave inversion (TWI) in electrocardiogram (ECG) is memory T-waves. This should be considered among the differentials of diffuse TWI in ECG of patients presenting to the emergency department (ED), especially when they have previous episodes of ventricular tachycardia (VT) or pacemaker implantation or Wolff-Parkinson-White syndrome. These TWIs are benign and do not require any treatment. However, it is of paramount importance for the emergency physician to differentiate it from ischemia-related T-wave changes. In the following case series, we report three cases of memory T-waves. Two of the cases had TWI in leads II, III, aVF, and V3 to V6 following reversion of VT. The other patient, with a VVI (Left ventricle paced, Left ventricle sensed, Inhibition to sensing) pacemaker, had memory T-waves in the ECG taken during normal sinus rhythm. In all the three patients, we considered memory T-waves to be the possible cause of TWI. The electrocardiographic diagnostic criteria for memory T-waves are positive T in lead aVL and positive/isoelectric T in the lead I; and precordial TWI >inferior TWI. These criteria are 92% sensitive and 100% specific. In the following case series, we also provide an algorithmic approach for patients with suspected memory T-waves in their 12-lead ECG when they present to the ED.
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Affiliation(s)
- R Gunaseelan
- Department of Emergency Medicine, Jawarharlal Institute of Postgraduate Medical Education and Research, Puducherry, India
| | - M Sasikumar
- Department of Emergency Medicine, Jawarharlal Institute of Postgraduate Medical Education and Research, Puducherry, India
| | - K Aswin
- Department of Emergency Medicine, Jawarharlal Institute of Postgraduate Medical Education and Research, Puducherry, India
| | - B Nithya
- Department of Emergency Medicine, Jawarharlal Institute of Postgraduate Medical Education and Research, Puducherry, India
| | - N Balamurugan
- Department of Emergency Medicine, Jawarharlal Institute of Postgraduate Medical Education and Research, Puducherry, India
| | - M Vivekanandan
- Department of Emergency Medicine, Jawarharlal Institute of Postgraduate Medical Education and Research, Puducherry, India
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14
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Haq KT, Javadekar N, Tereshchenko LG. Detection and removal of pacing artifacts prior to automated analysis of 12-lead ECG. Comput Biol Med 2021; 133:104396. [PMID: 33872969 DOI: 10.1016/j.compbiomed.2021.104396] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2021] [Revised: 04/05/2021] [Accepted: 04/09/2021] [Indexed: 10/21/2022]
Abstract
BACKGROUND Pacing artifacts must be excluded from the analysis of paced ECG waveform. This study aimed to develop and validate an algorithm to identify and remove the pacing artifacts on ECG and vectorcardiogram (VCG). METHODS We developed a semi-automatic algorithm that identifies the onset and offset of a pacing artifact based on the VCG signal slope steepness and designed a graphical user interface that permits quality control and fine-tuning the constraining threshold values. We used 1054 ECGs from the retrospective, multicenter cohort study "Global Electrical Heterogeneity and Clinical Outcomes," including 3825 atrial and 10,031 ventricular pacing artifacts for the algorithm development and 22 ECGs including 108 atrial and 241 ventricular pacing artifacts for validation. Validation was performed per digital sample. We used the kappa-statistic of interrater agreement between manually labeled sample (ground-truth) and automated detection. RESULTS The constraining parameter values were for onset threshold 13.06 ± 6.21 μV/ms, offset threshold 34.77 ± 17.80 μV/ms, and maximum window size 27.23 ± 3.53 ms. The automated algorithm detected a digital sample belonging to pacing artifact with a sensitivity of 74.5% and specificity of 99.6% and classified correctly 98.8% of digital samples (ROC AUC 0.871; 95%CI 0.853-0.878). The kappa-statistic was 0.785, indicating substantial agreement. The agreement was on 98.81% digital samples, significantly (P < 0.00001) larger than the random agreement on 94.43% of digital samples. CONCLUSIONS The semi-automated algorithm can detect and remove ECG pacing artifacts with high accuracy and provide a user-friendly interface for quality control.
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Affiliation(s)
- Kazi T Haq
- Oregon Health & Science University, Knight Cardiovascular Institute, Portland, OR, USA
| | - Neeraj Javadekar
- Oregon Health & Science University, Knight Cardiovascular Institute, Portland, OR, USA
| | - Larisa G Tereshchenko
- Oregon Health & Science University, Knight Cardiovascular Institute, Portland, OR, USA.
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15
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You T, Luo C, Zhang K, Zhang H. Electrophysiological Mechanisms Underlying T-Wave Alternans and Their Role in Arrhythmogenesis. Front Physiol 2021; 12:614946. [PMID: 33746768 PMCID: PMC7969788 DOI: 10.3389/fphys.2021.614946] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2020] [Accepted: 02/10/2021] [Indexed: 12/18/2022] Open
Abstract
T-wave alternans (TWA) reflects every-other-beat alterations in the morphology of the electrocardiogram ST segment or T wave in the setting of a constant heart rate, hence, in the absence of heart rate variability. It is believed to be associated with the dispersion of repolarization and has been used as a non-invasive marker for predicting the risk of malignant cardiac arrhythmias and sudden cardiac death as numerous studies have shown. This review aims to provide up-to-date review on both experimental and simulation studies in elucidating possible mechanisms underlying the genesis of TWA at the cellular level, as well as the genesis of spatially concordant/discordant alternans at the tissue level, and their transition to cardiac arrhythmia. Recent progress and future perspectives in antiarrhythmic therapies associated with TWA are also discussed.
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Affiliation(s)
- Tingting You
- Key Lab of Medical Electrophysiology, Ministry of Education, Institute of Cardiovascular Research, Southwest Medical University, Luzhou, China
| | - Cunjin Luo
- School of Computer Science and Electronic Engineering, University of Essex, Colchester, United Kingdom
| | - Kevin Zhang
- School of Medicine, Imperial College of London, London, United Kingdom
| | - Henggui Zhang
- Key Lab of Medical Electrophysiology, Ministry of Education, Institute of Cardiovascular Research, Southwest Medical University, Luzhou, China.,Department of Physics and Astronomy, University of Manchester, Manchester, United Kingdom
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16
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Haq KT, Cao J, Tereshchenko LG. Characteristics of Cardiac Memory in Patients with Implanted Cardioverter-defibrillators: The Cardiac Memory with Implantable Cardioverter-defibrillator (CAMI) Study. J Innov Card Rhythm Manag 2021; 12:4395-4408. [PMID: 33654571 PMCID: PMC7909362 DOI: 10.19102/icrm.2021.120204] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2020] [Accepted: 10/12/2020] [Indexed: 01/12/2023] Open
Abstract
This study sought to determine factors associated with cardiac memory (CM) in patients with implantable cardioverter-defibrillators (ICDs). Patients with structural heart disease [n = 20; mean age: 72.6 ± 11.6 years; 80% male; mean left ventricular ejection fraction (LVEF): 31.7 ± 7.6%; history of myocardial infarction in 75% and nonsustained ventricular tachycardia (NSVT) in 85%] and preserved atrioventricular conduction received dual-chamber ICDs for primary (80%) or secondary (20%) prevention. Standard 12-lead electrocardiograms were recorded in AAI and DDD modes before and after seven days of right ventricular (RV) pacing in DDD mode with a short atrioventricular delay. The direction (azimuth and elevation) and magnitude of spatial QRS, T, and spatial ventricular gradient vectors were measured before and after seven days of RV pacing. CM was quantified as the degree of alignment between QRSDDD-7 and TAAI-7 vectors (QRSDDD-7 –TAAI-7 angle). Circular statistics and mixed models with a random slope and intercept were adjusted for changes in cardiac activation, LVEF, known risk factors, and the use of medications known to affect CM occurring on days 1 through 7. The QRSDDD-7–TAAI-7 angle strongly correlated (circular r = −0.972; p < 0.0001) with a TAAI-7–TDDD-7 angle. In the mixed models, CM-T azimuth changes [+132° (95% confidence interval (CI): 80°–184°); p < 0.0001] were counteracted by the history of MI [−180° (95% CI: −320° to −40°); p = 0.011] and female sex [−162° (95% CI: −268° to −55°); p = 0.003]. A CM-T area increase [+15 (95% CI: 6–24) mV*ms; p < 0.0001] was amplified by NSVT history [+27 (95% CI: 4–46) mV*ms; p = 0.007]. These findings suggest that preexistent electrical remodeling affects CM in response to RV pacing, that CM exhibits saturation behavior, and that women reach CM saturation more easily than men.
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Affiliation(s)
- Kazi T Haq
- Knight Cardiovascular Institute, Oregon Health and Science University, Portland, OR, USA
| | - Jian Cao
- Medtronic, Inc., Minneapolis, MN, USA
| | - Larisa G Tereshchenko
- Knight Cardiovascular Institute, Oregon Health and Science University, Portland, OR, USA
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17
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Pierce JB, Rosenthal J, Stone NJ. Worth Remembering: Cardiac Memory Presenting as Deep Anterior T-Wave Inversions Explained by Intermittent Left Bundle Branch Block. Am J Cardiol 2020; 135:174-176. [PMID: 32866450 DOI: 10.1016/j.amjcard.2020.08.032] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/10/2020] [Revised: 08/17/2020] [Accepted: 08/21/2020] [Indexed: 10/23/2022]
Abstract
Cardiac memory is a common cause of deep T-wave inversions (TWI) in the anterior precordial leads and can be difficult to distinguish from alternative causes of TWI such as myocardial ischemia. Cardiac memory is generally a benign condition except in the setting of prolonged QT when it can contribute to the precipitation of torsades de pointes. Herein, we describe the presentation and clinical course of a case of cardiac memory due to intermittent left bundle branch block (LBBB) that presented asymptomatically to our outpatient cardiology clinic with deep anterior TWI. We discuss common causes of and mechanisms underlying cardiac memory and how to distinguish it from alternative causes of TWI based on 12-lead electrocardiogram. In conclusion, intermittent LBBB is an under-recognized cause of cardiac memory that can present as deep anterior TWI mimicking cardiac ischemia, and awareness of this clinical entity may help prevent unnecessary invasive and expensive testing on otherwise healthy patients.
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Affiliation(s)
- Jacob B Pierce
- Feinberg School of Medicine, Northwestern University, Chicago, Illinois
| | - James Rosenthal
- Division of Cardiology, Department of Medicine, Feinberg School of Medicine, Northwestern University, Chicago, Illinois; Bluhm Cardiovascular Institute, Northwestern Memorial Hospital, Chicago, Illinois
| | - Neil J Stone
- Division of Cardiology, Department of Medicine, Feinberg School of Medicine, Northwestern University, Chicago, Illinois; Bluhm Cardiovascular Institute, Northwestern Memorial Hospital, Chicago, Illinois.
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18
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Axelsson KJ, Gransberg L, Lundahl G, Vahedi F, Bergfeldt L. Adaptation of ventricular repolarization time following abrupt changes in heart rate: comparisons and reproducibility of repeated atrial and ventricular pacing. Am J Physiol Heart Circ Physiol 2020; 320:H381-H392. [PMID: 33164576 DOI: 10.1152/ajpheart.00542.2020] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Adequate adaptation of ventricular repolarization (VR) duration to changes in heart rate (HR) is important for cardiac electromechanical function and electrical stability. We studied the QT and QTpeak adaptation in response to abrupt start and stop of atrial and ventricular pacing on two occasions with an interval of at least 1 mo in 25 study subjects with permanent pacemakers. Frank vectorcardiography was used for data collection. Atrial or ventricular pacing was performed for 8 min aiming at a cycle length (CL) of 500 ms. We measured the immediate response (IR), the time constant (τ) of the exponential phase, and T90 End, the time to reach 90% change of QT and QTpeak from baseline to steady state during and after pacing. During atrial pacing, the CL decreased on average 45% from mean (SD) 944 (120) to 518 (46) ms and QT decreased on average 18% from 388 (20) to 318 (17) ms. For QT, T90 End was 103 (24) s and 126 (15) s after start versus stop of atrial pacing; a difference of 24 (27) s (P = 0.006). The response pattern was similar for τ but IR did not differ significantly between pacing start and stop. The response pattern was similar for QTpeak and also for QT and QTpeak following ventricular pacing start and stop. The coefficients of variation for repeated measures were 7%-21% for T90 End and τ. In conclusion, the adaptation of VR duration was significantly more rapid following increasing than decreasing HR and intraindividually a relatively reproducible process.NEW & NOTEWORTHY We studied the duration of ventricular repolarization (VR) adaptation and its hysteresis, following increasing and decreasing heart rate by abrupt start and stop of 8-min atrial or ventricular pacing in study subjects with permanent pacemakers and repeated the protocol with ≥1 mo interval, a novel approach. VR adaptation was significantly longer following decreasing than increasing heart rate corroborating previous observations. Furthermore, VR adaptation was intraindividually a reproducible and, hence, robust phenomenon, a novel finding.
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Affiliation(s)
- Karl-Jonas Axelsson
- Department of Molecular and Clinical Medicine, Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.,Department of Cardiology, Region Västra Götaland, Sahlgrenska University Hospital, Gothenburg Sweden
| | - Lennart Gransberg
- Department of Molecular and Clinical Medicine, Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Gunilla Lundahl
- Department of Molecular and Clinical Medicine, Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Farzad Vahedi
- Department of Molecular and Clinical Medicine, Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.,Department of Cardiology, Region Västra Götaland, Sahlgrenska University Hospital, Gothenburg Sweden
| | - Lennart Bergfeldt
- Department of Molecular and Clinical Medicine, Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.,Department of Cardiology, Region Västra Götaland, Sahlgrenska University Hospital, Gothenburg Sweden
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19
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Kichloo A, Haji AQ, Kanjwal K. Cardiac memory presenting as ST elevations following premature ventricular complex ablation. HeartRhythm Case Rep 2020; 7:52-55. [PMID: 33505856 PMCID: PMC7813796 DOI: 10.1016/j.hrcr.2020.10.011] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Affiliation(s)
- Asim Kichloo
- Department of Internal Medicine, Samaritan Medical Center, Watertown, New York
- Department of Internal Medicine, Central Michigan University, Saginaw, Michigan
| | - Abdul Qadir Haji
- Department of Cardiology, Martinsburg VA Medical Center, Martinsburg, West Virginia
| | - Khalil Kanjwal
- Department of Electrophysiology, McLaren Greater Lansing Hospital, Lansing, Michigan
- Address reprint requests and correspondence: Dr Khalil Kanjwal, Clinical Associate Professor of Medicine, Michigan State University, McLaren Greater Lansing Hospital, Lansing, MI 48901.
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20
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Abstract
Cardiac memory (CM) is a commonly unrecognized entity in which electrocardiograph (EKG) changes demonstrate T wave inversions (TWI) that appear consistent with ischemia. Inability to recognize and distinguish CM from actual ischemia can be a burden for both patients and hospitals, leading to unnecessary hospital admission, cardiac testing, and cardiac catheterization. Simple EKG analysis and meticulous interpretation of T-wave axis and morphology can help differentiate between the two. We present a case with such a dilemma, and an overview literature and physiology behind this entity.
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Affiliation(s)
- Rastko Rakočević
- Internal Medicine, University Hospital - Rutgers New Jersey Medical School, Newark, USA.,Pulmonary and Critical Care Medicine, University of Southern California, Los Angeles, USA
| | - Renjit Thomas
- Cardiology, University Hospital - Rutgers New Jersey Medical School, Newark, USA
| | - Ralph G Oriscello
- Cardiology/Critical Care, Veterans Affairs (VA) East Orange/Rutgers New Jersey Medical School, East Orange, USA
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21
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Zhong C, Jiang Z, Zhou X, Shan Q. Reversion of cardiac memory during left bundle branch pacing. J Electrocardiol 2020; 59:81-83. [PMID: 32023497 DOI: 10.1016/j.jelectrocard.2020.01.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2019] [Revised: 12/31/2019] [Accepted: 01/03/2020] [Indexed: 10/25/2022]
Abstract
Cardiac memory (CM) is identified as an altered T wave when normal ventricular activation resumes after an abnormal myocardial activation period. We present a case who initially underwent temporary right ventricular apex (RVA) pacing for one week which induced typical pseudo-primary T wave changes. The T wave inversion was observed after the end of RVA pacing when left bundle branch pacing (LBBP) was initiated, and the abnormal T waves gradually return to almost normal repolarization during LBBP 40 days later.
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Affiliation(s)
- Chenghao Zhong
- Department of Cardiology, The First Affiliated Hospital of Nanjing Medical University, Nanjing 210029, China; Department of Cardiology, The Third Affiliated Hospital of Soochow University, Changzhou 213003, China
| | - Zhixin Jiang
- Department of Cardiology, The First Affiliated Hospital of Nanjing Medical University, Nanjing 210029, China
| | - Xiujuan Zhou
- Department of Cardiology, The First Affiliated Hospital of Nanjing Medical University, Nanjing 210029, China
| | - Qijun Shan
- Department of Cardiology, The First Affiliated Hospital of Nanjing Medical University, Nanjing 210029, China.
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22
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Suran MCB, Margulescu AD, Bruja R, Siliste C, Vinereanu D. Surface ECG criteria can discriminate post-septal pacing cardiac memory from ischemic T wave inversions. J Electrocardiol 2020; 58:10-17. [PMID: 31678715 DOI: 10.1016/j.jelectrocard.2019.10.004] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2019] [Revised: 09/23/2019] [Accepted: 10/11/2019] [Indexed: 10/25/2022]
Abstract
Cardiac memory (CM) refers to transient T wave changes that appear after cessation of a period of abnormal ventricular activation, such as right ventricular (RV) pacing. ECG criteria for differentiating post-pacing CM from ischemia-induced T wave changes were previously published only for apical, but not for septal RV pacing. AIM To find ECG criteria for discriminating post-septal pacing CM from ischemic T wave inversions. METHODS ECGs were analyzed in 2 groups: CM (n = 23) and ischemia (n = 26). CM was induced by 2 weeks of DDD pacing with a short AV delay. Ischemic patients were grouped by culprit vessel: left anterior descending (LAD), circumflex (Cx), right coronary artery (RCA). RESULTS CM was visible on the ECG after 1 week of ventricular pacing, started to disappear in <1 week after pacing cessation and was completely reversible within 4 weeks of pacing cessation. T wave axis differed between CM (75.8 ± 18.5°) and Cx (-25.2 ± 25.5°, p < 0.01) and RCA (-18.3 ± 18.9°, p < 0.01) groups, but not compared to LAD group (96.4 ± 65.0°, p = 0.17). The combination of (1) positive T wave in aVF; and (2) (i) T wave amplitude in aVF ≥ the absolute value of the most negative precordial T wave, or (ii) positive T wave in V5 and positive or isoelectric T wave in lead I identified CM from all ischemia with a sensitivity of 91% and a specificity of 92%. CONCLUSION ECG criteria can discriminate post-septal RV pacing CM from ischemic changes with high sensitivity and specificity.
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Affiliation(s)
- Maria-Claudia-Berenice Suran
- University of Medicine and Pharmacy "Carol Davila" Bucharest, Bucharest, Romania; Department of Cardiology, University and Emergency Hospital of Bucharest, Bucharest, Romania
| | - Andrei-Dumitru Margulescu
- University of Medicine and Pharmacy "Carol Davila" Bucharest, Bucharest, Romania; Department of Cardiology, University and Emergency Hospital of Bucharest, Bucharest, Romania; Department of Cardiology, Morriston Hospital NHS Trust, Swansea, United Kingdom
| | - Ramona Bruja
- Department of Cardiology, University and Emergency Hospital of Bucharest, Bucharest, Romania
| | - Calin Siliste
- University of Medicine and Pharmacy "Carol Davila" Bucharest, Bucharest, Romania; Department of Cardiology, University and Emergency Hospital of Bucharest, Bucharest, Romania.
| | - Dragos Vinereanu
- University of Medicine and Pharmacy "Carol Davila" Bucharest, Bucharest, Romania; Department of Cardiology, University and Emergency Hospital of Bucharest, Bucharest, Romania
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23
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Ali H, Lupo P, Foresti S, De Ambroggi G, Mantovani R, De Lucia C, Passarelli I, De Ambroggi L, Cappato R. Nearly fatal ventricular arrhythmia following pacemaker implantation in a young female with complete heart block. J Arrhythm 2019; 35:766-769. [PMID: 31624519 PMCID: PMC6787159 DOI: 10.1002/joa3.12220] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2019] [Revised: 05/31/2019] [Accepted: 06/17/2019] [Indexed: 11/11/2022] Open
Abstract
This case concerns a 24-year-old female who developed malignant ventricular tachyarrhythmia a few weeks after pacemaker implantation for complete heart block. Apparently, right ventricular pacing caused significant repolarization abnormalities in both native and paced rhythms with marked QT prolongation and substantial electrical instability. This case highlights other intriguing phenomena in the puzzle of cardiac repolarization and how pacing therapy may alter this complex process providing arrhythmic substrate in vulnerable subjects. Though such arrhythmic events are clinically rare, vulnerable patients or with suspected myocardial disease that may cause QT prolongation should be carefully followed in the course of pacing therapy.
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Affiliation(s)
- Hussam Ali
- Arrhythmia & EP Research CenterIRCCS Humanitas Research & University HospitalRozzano (Milan)Italy
| | - Pierpaolo Lupo
- Arrhythmia & EP Research CenterIRCCS Humanitas Research & University HospitalRozzano (Milan)Italy
| | - Sara Foresti
- Arrhythmia & EP Research CenterIRCCS Humanitas Research & University HospitalRozzano (Milan)Italy
| | - Guido De Ambroggi
- Arrhythmia & EP Research CenterIRCCS Humanitas Research & University HospitalRozzano (Milan)Italy
| | - Riccardo Mantovani
- Arrhythmia & EP Research CenterIRCCS Humanitas Research & University HospitalRozzano (Milan)Italy
| | - Carmine De Lucia
- Arrhythmia & EP Research CenterIRCCS Humanitas Research & University HospitalRozzano (Milan)Italy
| | - Ilaria Passarelli
- Arrhythmia & EP Research CenterIRCCS Humanitas Research & University HospitalRozzano (Milan)Italy
| | | | - Riccardo Cappato
- Arrhythmia & EP Research CenterIRCCS Humanitas Research & University HospitalRozzano (Milan)Italy
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24
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Iríbar Diéguez IK, Guitera Rubio I. Efecto de memoria cardiaca. Aten Primaria 2019; 51:516-517. [PMID: 30718026 PMCID: PMC6836915 DOI: 10.1016/j.aprim.2018.09.018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2018] [Accepted: 09/24/2018] [Indexed: 12/04/2022] Open
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25
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Siontis KC, Wen S, Asirvatham SJ. Cardiac memory for the clinical electrophysiologist. J Cardiovasc Electrophysiol 2019; 30:2140-2143. [DOI: 10.1111/jce.14134] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/08/2019] [Accepted: 08/08/2019] [Indexed: 11/30/2022]
Affiliation(s)
| | - Songnan Wen
- Department of Cardiovascular DiseasesMayo ClinicRochester Minnesota
| | - Samuel J. Asirvatham
- Department of Cardiovascular DiseasesMayo ClinicRochester Minnesota
- Department of Pediatrics and Adolescent MedicineMayo ClinicRochester Minnesota
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26
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Grimm W, Luck K, Greene B, Parahuleva M. [Cardiac memory following pacemaker implantation]. Herzschrittmacherther Elektrophysiol 2019; 30:404-408. [PMID: 31562545 DOI: 10.1007/s00399-019-00646-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2019] [Accepted: 09/05/2019] [Indexed: 11/30/2022]
Abstract
BACKGROUND Although T wave inversions due to cardiac memory were described already 50 years ago, little is known about the prevalence and about clinical predictors of this phenomenon. METHODS After exclusion of 238 patients due to bundle branch block or pacemaker dependency, a total of 325 consecutive patients were enrolled in this study during routine outpatient control of their pacemaker. A 12-lead standard ECG was obtained in all patients during transient inhibition of pacing therapy. RESULTS Cardiac memory could be documented in 115 of 325 patients (35%) and showed a strong association with the amount of ventricular stimulation. The prevalence of cardiac memory was 9% in patients with ≤25% ventricular stimulation and 86% in patients with ≥75% ventricular stimulation. DISCUSSION Cardiac memory was observed in one third of patients following pacemaker implantation. The prevalence of cardiac memory in the ECG with intrinsic rhythm is above 80% in patients with frequent ventricular stimulation. Cardiac memory due to ventricular stimulation is benign and should not be confused with similar T wave inversions due to acute coronary syndrome, severe left ventricular hypertrophy, or myocarditis.
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Affiliation(s)
- Wolfram Grimm
- Universitätsklinik Marburg, Klinik für Innere Medizin - Kardiologie, Angiologie und Intensivmedizin, UKGM Gießen und Marburg, Standort Marburg, Baldingerstraße, 35033, Marburg, Deutschland.
| | - Kathrin Luck
- Universitätsklinik Marburg, Klinik für Innere Medizin - Kardiologie, Angiologie und Intensivmedizin, UKGM Gießen und Marburg, Standort Marburg, Baldingerstraße, 35033, Marburg, Deutschland
| | - Brandon Greene
- Institut für Medizinische Bioinformatik und Biostatistik, Philipps Universität Marburg., Marburg, Deutschland
| | - Mariana Parahuleva
- Universitätsklinik Marburg, Klinik für Innere Medizin - Kardiologie, Angiologie und Intensivmedizin, UKGM Gießen und Marburg, Standort Marburg, Baldingerstraße, 35033, Marburg, Deutschland
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27
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Nakashima T, Takasugi N, Sahashi Y, Hatasa M, Kanamori H, Okura H. Cardiac memory-related QT prolongation during right bundle-branch block in a patient with pre-existing left bundle-branch block. J Cardiovasc Electrophysiol 2019; 30:2137-2139. [PMID: 31478279 DOI: 10.1111/jce.14133] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/13/2019] [Revised: 07/02/2019] [Accepted: 07/09/2019] [Indexed: 11/29/2022]
Affiliation(s)
- Takashi Nakashima
- Department of Cardiology, Graduate School of Medicine, Gifu University, Gifu, Japan
| | - Nobuhiro Takasugi
- Department of Cardiology, Graduate School of Medicine, Gifu University, Gifu, Japan
| | - Yuki Sahashi
- Department of Cardiology, Graduate School of Medicine, Gifu University, Gifu, Japan
| | - Masanori Hatasa
- Department of Cardiology, Gujo Municipal Hospital, Gujo, Japan
| | - Hiromitsu Kanamori
- Department of Cardiology, Graduate School of Medicine, Gifu University, Gifu, Japan
| | - Hiroyuki Okura
- Department of Cardiology, Graduate School of Medicine, Gifu University, Gifu, Japan
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28
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Parreira L, Carmo P, Adragão P, Pinho J, Budanova M, Zubarev S, Cavaco D, Marinheiro R, Carmo J, Costa F, Marques H, Goncalves P. Non-invasive electrocardiographic imaging in patients with idiopathic premature ventricular contractions from the right ventricular outflow tract: New insights into arrhythmia substrate. J Electrocardiol 2019; 57:69-76. [PMID: 31514015 DOI: 10.1016/j.jelectrocard.2019.08.046] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2019] [Revised: 08/19/2019] [Accepted: 08/30/2019] [Indexed: 11/17/2022]
Abstract
AIMS The aim of this study was to use non-invasive electrocardiographic imaging (ECGI) to study the electrophysiological properties of right ventricular outflow tract (RVOT) in patients with frequent premature ventricular contractions (PVCs) from the RVOT and in controls. METHODS ECGI is a combined application of body surface electrocardiograms and computed tomography or magnetic resonance imaging data. Unipolar electrograms are reconstructed on the epicardial and endocardial surfaces. Activation time (AT) was defined as the time of maximal negative slope of the electrogram (EGM) during QRS, recovery time (RT) as the time of maximal positive slope of the EGM during T wave, Activation recovery interval (ARI) was defined as the difference between RT and AT. ARI dispersion (Δ ARI) and RT dispersion (Δ RT) were calculated as the difference between maximal and minimal ARI and RT respectively. We evaluated those parameters in patients with frequent PVCs from the RVOT, defined as >10.000 per 24 h, and in a control group. RESULTS We studied 7 patients with frequent RVOT PVCs and 17 controls. Patients with PVCs from the RVOT had shorter median RT than controls, in the endocardium and in the epicardium, respectively 380 (239-397) vs 414 (372-448) ms, p = 0.047 and 275 (236-301) vs 330 (263-418) ms, p = 0.047. The dispersion of ARI and of RT in the epicardium was higher than in controls, Δ ARI of 145 (68-216) vs 17 (3-48) ms, p = 0.001 and Δ RT of 201 (160-235) vs 115 (65-177), p = 0.019. CONCLUSION In this group of patients we found a shorter median RT in the endocardium and in the epicardium of the RVOT and a higher dispersion of the ARI and RT across the epicardium in patients with PVCs from the RVOT when comparing to controls.
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Affiliation(s)
| | - Pedro Carmo
- Hospital Luz Lisboa, Av Lusiada 1500-650, Lisboa, Portugal
| | - Pedro Adragão
- Hospital Luz Lisboa, Av Lusiada 1500-650, Lisboa, Portugal
| | - Joana Pinho
- Hospital Luz Lisboa, Av Lusiada 1500-650, Lisboa, Portugal
| | | | - Stepan Zubarev
- Hospital Luz Lisboa, Av Lusiada 1500-650, Lisboa, Portugal
| | - Diogo Cavaco
- Hospital Luz Lisboa, Av Lusiada 1500-650, Lisboa, Portugal
| | | | - João Carmo
- Hospital Luz Lisboa, Av Lusiada 1500-650, Lisboa, Portugal
| | | | - Hugo Marques
- Hospital Luz Lisboa, Av Lusiada 1500-650, Lisboa, Portugal
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Wellens HJ. QRS complex change during carotid sinus massage in ventricular pre-excitation. Heart Rhythm 2019; 16:1296-1298. [PMID: 31358267 DOI: 10.1016/j.hrthm.2019.03.020] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/18/2019] [Indexed: 11/28/2022]
Affiliation(s)
- Hein J Wellens
- Cardiovascular Research Institute, Maastricht, The Netherlands.
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Vohra J. Editorial: Cardiac or T wave memory after radiofrequency ablation of right ventricular outflow tract ectopics. J Cardiovasc Electrophysiol 2019; 30:1557-1559. [PMID: 31165545 DOI: 10.1111/jce.14007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/21/2019] [Accepted: 05/27/2019] [Indexed: 11/30/2022]
Affiliation(s)
- Jitendra Vohra
- Cardiology Department, The Royal Melbourne Hospital, University of Melbourne, Melbourne, Victoria, Australia
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Sakamoto Y, Inden Y, Okamoto H, Mamiya K, Tomomatsu T, Fujii A, Yanagisawa S, Shibata R, Hirai M, Murohara T. T-wave changes of cardiac memory caused by frequent premature ventricular contractions originating from the right ventricular outflow tract. J Cardiovasc Electrophysiol 2019; 30:1549-1556. [PMID: 31157487 DOI: 10.1111/jce.14008] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/23/2019] [Revised: 04/16/2019] [Accepted: 04/30/2019] [Indexed: 11/28/2022]
Abstract
INTRODUCTION Cardiac memory is recognized as altered T-waves when the sinus rhythm resumes after an abnormal myocardial activation period that recovers slowly over several weeks. The T-wave changes after ablation of frequent premature ventricular contractions (PVCs) as cardiac memory was not known. OBJECTIVE This study identified whether cardiac memory exists after successful ablation of PVCs from the right ventricular outflow tract (RVOT). METHODS We investigated 45 patients who underwent successful ablation of PVCs from RVOT and 10 patients who underwent unsuccessful ablation. We analyzed the amplitude of the T-wave, QT intervals, and QRST time-integral values of a 12-lead electrocardiogram before ablation and 1 day, 3 days, and 1 month after ablation. RESULTS In the successful ablation group, the amplitude of the T-wave and QRST time-integral values of lead II, III, aVR, aVL, and aVF significantly changed after ablation and gradually normalized within 1 month. In addition, if the number of pre-ablation PVCs was small, then the corresponding impact was also small. However, the greater the number of pre-ablation PVCs, the more prominent the changes. Significant changes were not observed in the unsuccessful ablation group. CONCLUSION When ablation of PVCs from RVOT was successful, primary T-wave changes because of cardiac memory and the gradual normalization of the amplitude of the T-wave were observed. No significant T-wave changes were detected after unsuccessful ablation.
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Affiliation(s)
- Yusuke Sakamoto
- Department of Cardiology, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Yasuya Inden
- Department of Cardiology, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Hiroya Okamoto
- Department of Cardiology, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Keita Mamiya
- Department of Cardiology, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Toshiro Tomomatsu
- Department of Cardiology, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Aya Fujii
- Department of Cardiology, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Satoshi Yanagisawa
- Department of Cardiology, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Rei Shibata
- Department of Cardiology, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Makoto Hirai
- Department of Cardiology, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Toyoaki Murohara
- Department of Cardiology, Nagoya University Graduate School of Medicine, Nagoya, Japan
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New T Wave Inversions Post Synchronized Cardioversion in a Patient With a Ventricular Pacemaker. Ann Emerg Med 2019; 73:627-630. [DOI: 10.1016/j.annemergmed.2018.12.022] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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Tafoya C, Singh A. Cardiac Memory: A Case Report and Review of the Literature. J Emerg Med 2019; 57:85-93. [PMID: 31047746 DOI: 10.1016/j.jemermed.2019.02.018] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2018] [Revised: 02/16/2019] [Accepted: 02/18/2019] [Indexed: 11/24/2022]
Abstract
BACKGROUND A variety of clinical syndromes can cause T-wave inversion (TWI), ranging from life-threatening events to benign conditions. One benign cause of TWI is cardiac memory, which is characterized by the transient inversion of T-waves following abnormal activation of the ventricles, commonly due to intermittent left bundle branch block (LBBB), tachydysrhythmias, electrical pacing, or ventricular pre-excitation. CASE REPORT A 72-year-old man presented to the emergency department with chest pain, nausea, vomiting, and headache. Upon arrival, his electrocardiogram (ECG) showed new-onset LBBB with appropriate secondary ST-T wave changes. A subsequent ECG showed disappearance of LBBB and newly inverted T-waves in precordial leads V1-V5, followed by a repeat ECG that again showed LBBB. Serial troponin testing was unremarkable. During hospitalization, echocardiogram and nuclear perfusion stress test were normal. The transient TWIs in this patient were believed to be due to cardiac memory. We performed a literature review and identified 39 published cases of cardiac memory. The most common etiology for cardiac memory was after cardiac pacemaker placement, followed by intermittent LBBB (as was seen in our patient), and post-tachydysrhythmia. Patient ages ranged from 21 to 88 years, with an equal number of cases reported in men and women. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: Cardiac memory is a poorly understood, rarely observed phenomenon that can occur in the setting of intermittent LBBB. Testing for acute cardiac ischemia and underlying coronary artery disease is still recommended, as the diagnosis of cardiac memory can only be made after negative workup.
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Affiliation(s)
- Chelsea Tafoya
- Department of Emergency Medicine, Alameda Health System, Highland Hospital, Oakland, California
| | - Amandeep Singh
- Department of Emergency Medicine, Alameda Health System, Highland Hospital, Oakland, California
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Brüggemann B, Eitel C, Graf T, Grimm K, Grimm W, Heeger C, Israel CW, Krauspe J, Kalantaryan V, Langer H, Luck K, Mischke K, Parahuleva M, Tilz RR, Touati S, Tribunyan S, Vogler J. [ECG signs of acute coronary syndrome]. Herzschrittmacherther Elektrophysiol 2019; 30:89-101. [PMID: 30825042 DOI: 10.1007/s00399-019-0613-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2018] [Accepted: 01/29/2019] [Indexed: 11/30/2022]
Affiliation(s)
- Ben Brüggemann
- Medizinische Klinik II/Kardiologie, Angiologie und Intensivmedizin, Universitätsklinikum Schleswig-Holstein, Campus Lübeck, Lübeck, Deutschland
| | - Charlotte Eitel
- Medizinische Klinik II/Kardiologie, Angiologie und Intensivmedizin, Universitätsklinikum Schleswig-Holstein, Campus Lübeck, Lübeck, Deutschland
| | - Tobias Graf
- Medizinische Klinik II/Kardiologie, Angiologie und Intensivmedizin, Universitätsklinikum Schleswig-Holstein, Campus Lübeck, Lübeck, Deutschland
| | - Kathrin Grimm
- Universitätsklinik Marburg, Klinik für Innere Medizin - Kardiologie, Angiologie und Intensivmedizin, UKGM Gießen und Marburg, Standort Marburg, 35033, Marburg, Deutschland
| | - Wolfram Grimm
- Universitätsklinik Marburg, Klinik für Innere Medizin - Kardiologie, Angiologie und Intensivmedizin, UKGM Gießen und Marburg, Standort Marburg, 35033, Marburg, Deutschland.
| | - Christian Heeger
- Medizinische Klinik II/Kardiologie, Angiologie und Intensivmedizin, Universitätsklinikum Schleswig-Holstein, Campus Lübeck, Lübeck, Deutschland
| | - Carsten W Israel
- Klinik für Innere Medizin - Kardiologie, Diabetologie & Nephrologie, Evangelisches Klinikum Bethel, Bielefeld, Deutschland
| | - Jan Krauspe
- Klinik für Kardiologie, Nephrologie, Pneumologie, Angiologie und internistische Intensivmedizin, Leopoldina-Krankenhaus der Stadt Schweinfurt, Gustav-Adolf-Str. 8, 97422, Schweinfurt, Deutschland
| | - Vazgen Kalantaryan
- Dept. of Medicine - Division of Cardiology, Medical Center Shengavit, Manandyan 9, 0006, Yerevan, Armenien.
| | - Harald Langer
- Medizinische Klinik II/Kardiologie, Angiologie und Intensivmedizin, Universitätsklinikum Schleswig-Holstein, Campus Lübeck, Lübeck, Deutschland
| | - Kathrin Luck
- Universitätsklinik Marburg, Klinik für Innere Medizin - Kardiologie, Angiologie und Intensivmedizin, UKGM Gießen und Marburg, Standort Marburg, 35033, Marburg, Deutschland
| | - Karl Mischke
- Klinik für Kardiologie, Nephrologie, Pneumologie, Angiologie und internistische Intensivmedizin, Leopoldina-Krankenhaus der Stadt Schweinfurt, Gustav-Adolf-Str. 8, 97422, Schweinfurt, Deutschland.
| | - Marianna Parahuleva
- Universitätsklinik Marburg, Klinik für Innere Medizin - Kardiologie, Angiologie und Intensivmedizin, UKGM Gießen und Marburg, Standort Marburg, 35033, Marburg, Deutschland
| | - Roland Richard Tilz
- Medizinische Klinik II/Kardiologie, Angiologie und Intensivmedizin, Universitätsklinikum Schleswig-Holstein, Campus Lübeck, Lübeck, Deutschland. .,Universitäres Herzzentrum Lübeck, Medizinische Klinik II - Kardiologie, Angiologie, Intensivmedizin, Universitätsklinikum Schleswig-Holstein, Ratzeburger Allee 160, Haus 40, 23538, Lübeck, Deutschland.
| | - Soumia Touati
- Medizinische Klinik II/Kardiologie, Angiologie und Intensivmedizin, Universitätsklinikum Schleswig-Holstein, Campus Lübeck, Lübeck, Deutschland
| | - Sona Tribunyan
- Klinik für Innere Medizin - Kardiologie, Diabetologie & Nephrologie, Evangelisches Klinikum Bethel, Bielefeld, Deutschland
| | - Julia Vogler
- Medizinische Klinik II/Kardiologie, Angiologie und Intensivmedizin, Universitätsklinikum Schleswig-Holstein, Campus Lübeck, Lübeck, Deutschland
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Kesmia M, Boughaba S, Jacquir S. Nonlinear dynamics of two-dimensional cardiac action potential duration mapping model with memory. J Math Biol 2019; 78:1529-1552. [DOI: 10.1007/s00285-018-1318-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2018] [Revised: 12/02/2018] [Indexed: 12/27/2022]
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Jensen JR, Kragholm K, Bødker KW, Mortensen R, Graff C, Pietersen A, Nielsen JB, Polcwiartek C, Tayal B, Torp-Pedersen C, Søgaard P, Hansen SM. Association between T-wave discordance and the development of heart failure in left bundle branch block patients: Results from the Copenhagen ECG study. J Electrocardiol 2018; 52:39-45. [PMID: 30476637 DOI: 10.1016/j.jelectrocard.2018.11.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2018] [Revised: 10/26/2018] [Accepted: 11/01/2018] [Indexed: 01/02/2023]
Abstract
BACKGROUND In left bundle branch block (LBBB), discrepancies between depolarization and repolarization of the heart can be assessed by similar direction (concordant) or opposite direction (discordant) of the lateral T-waves compared to the direction of the QRS complex and by the QRS-T angle. We examined the association between discordant T-waves and high QRS-T angles for heart failure development in primary care LBBB patients. METHODS Between 2001 and 2011, we identified 2540 patients from primary care with LBBB without overt heart failure. We examined the development of heart failure in relation to two ECG measures: (1) LBBB as either discordant (two or three monophasic T-waves in the opposite direction of the QRS complex in leads I, V5 or V6) or concordant, and (2) the frontal plane QRS-T angle in quartile groups. RESULTS In total, 244 of 913 patients (26.7%) with discordant LBBB developed heart failure compared to 302 of 1627 patients (16.7%) with concordant LBBB. Multivariable Cox regression comparing discordant with concordant LBBB showed a hazard ratio (HR) of 2.58 (95% Confidence interval [CI] 1.71-3.89) for heart failure development within 30 days of follow-up and a HR of 1.45 (95%CI 1.19-1.77) after 30 days. For QRS-T angle, comparing the highest quartile (160°-180°) with the lowest quartile (0°-110°) we found a HR of 2.25 (95%CI 1.26-4.02) within 30 days and a HR of 1.67 (95%CI 1.25-2.23) after 30 days. CONCLUSION T-wave discordance in lateral ECG leads and a high QRS-T angle are associated with heart failure development in primary care LBBB patients.
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Affiliation(s)
- Johannes Riis Jensen
- Unit of Epidemiology and Biostatistics, Aalborg University Hospital, Aalborg, Denmark.
| | - Kristian Kragholm
- Unit of Epidemiology and Biostatistics, Aalborg University Hospital, Aalborg, Denmark; Department of Cardiology, Aalborg University Hospital, Aalborg, Denmark
| | | | - Rikke Mortensen
- Unit of Epidemiology and Biostatistics, Aalborg University Hospital, Aalborg, Denmark
| | - Claus Graff
- Department of Health Science and Technology, Aalborg University, Aalborg, Denmark
| | - Adrian Pietersen
- Division of Cardiovascular Medicine, Department of Internal Medicine, University of Michigan, Ann Arbor, USA
| | | | - Christoffer Polcwiartek
- Unit of Epidemiology and Biostatistics, Aalborg University Hospital, Aalborg, Denmark; Department of Cardiology, Aalborg University Hospital, Aalborg, Denmark
| | - Bhupendar Tayal
- Department of Cardiology, Nephrology and Endocrinology, Nordsjaellands Hospital, Hilleroed, Denmark
| | | | - Peter Søgaard
- Department of Cardiology, Aalborg University Hospital, Aalborg, Denmark
| | - Steen Møller Hansen
- Unit of Epidemiology and Biostatistics, Aalborg University Hospital, Aalborg, Denmark
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Ibarrola M. Multiple myocardial bridges associated with left-ventricular dysfunction, intermittent left bundle branch block, and cardiac memory: A case report. Ann Noninvasive Electrocardiol 2018; 24:e12594. [PMID: 30117721 DOI: 10.1111/anec.12594] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/24/2018] [Accepted: 07/25/2018] [Indexed: 11/28/2022] Open
Abstract
Myocardial bridges are a congenital anomaly in which a segment of the coronary artery takes a "tunneled" intramuscular course. Few reports have associated myocardial bridges with left-ventricular dysfunction in patients with ischemia. Intermittent left bundle branch block is a conduction disturbance that has been described to be associated with myocardial bridges and cardiac memory. This study reports unusual associations of multiple myocardial bridges, angina, left-ventricular dysfunction, intermittent left bundle branch block, and cardiac memory.
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Peck D, Al-Kaisey A. Cardiac memory: an under-recognised cause of deep T wave inversion in a patient presenting with chest pain. BMJ Case Rep 2018; 2018:bcr-2018-225476. [PMID: 30061136 DOI: 10.1136/bcr-2018-225476] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
T wave inversion (TWI) has many differential diagnoses with acute myocardial ischaemia being the highest on the list of potential causes. Cardiac T wave memory is a benign, under-recognised and clinically important phenomenon seen after periods of altered ventricular conduction. After normal ventricular conduction is restored, the T wave 'remembers' and mirrors the direction of the wide QRS complex. Therefore, negative T waves are seen in leads that had negative wide QRS complexes. We describe the case of a 60-year-old truck driver with chest pain, deep TWI and traditional cardiovascular risk factors. After ruling out significant myocardial ischaemia, it was crucial to determine the cause of his T wave changes to provide reassurance and provide commercial license medical clearance. While it is currently a diagnosis of exclusion, it remains an important clinical entity for clinicians to recognise to provide an explanation for certain T wave changes to avoid future unnecessary cardiac testing.
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Affiliation(s)
- Daniel Peck
- Department of Cardiology, Austin Heath, Heidelberg, Australia
| | - Ahmed Al-Kaisey
- Department of Cardiology, Austin Heath, Heidelberg, Australia
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39
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Seibolt L, Maestas C, Lazkani M, Fatima U, Loli A, Chesser M. Rate-related left bundle branch block and cardiac memory in a patient with bradycardia: Case report and literature review. Clin Cardiol 2018; 41:1097-1102. [PMID: 29920728 DOI: 10.1002/clc.22997] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/31/2018] [Revised: 06/08/2018] [Accepted: 06/12/2018] [Indexed: 11/08/2022] Open
Abstract
Rate-related left bundle branch block (LBBB) is a well-studied phenomenon. Cardiac memory is another physiologic phenomenon in which T-wave abnormalities occur in the absence of ischemia. The association between these 2 phenomena has been described in several case reports. A literature review was performed through Ovid and PubMed, where at total of 93 cases of rate-related LBBB were identified. Cases were reviewed, and data were collected on rates of appearance and disappearance as well as the presence or absence of cardiac memory. There is some overlap in the rate at which LBBB appears. Cardiac memory is associated with rate-related LBBB in several cases, but its true prevalence is unknown. Cardiac memory is a phenomenon that is well described in the literature but is often underrecognized in clinical practice. As a consequence of overlooking this phenomenon and not including cardiac memory in the differential when T-wave abnormalities are observed, patients may be subjected to unnecessary invasive diagnostic testing.
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Affiliation(s)
- Luke Seibolt
- Department of Cardiology, Banner University, Medical Center, Phoenix, Arizona
| | - Camila Maestas
- Department of Internal Medicine, Banner University Medical Center, Phoenix, Arizona
| | - Mohamad Lazkani
- Department of Cardiology, Banner University, Medical Center, Phoenix, Arizona
| | - Umaima Fatima
- Department of Cardiology, Phoenix Veterans Affairs Medical Center, Phoenix, Arizona
| | - Akil Loli
- Department of Cardiology, Banner University, Medical Center, Phoenix, Arizona
| | - Michael Chesser
- Department of Internal Medicine, Phoenix Veterans Affairs Medical Center, Phoenix, Arizona
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40
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Mauricio B. Rosenbaum and the Argentinian School of Electrocardiography. J Electrocardiol 2018; 51:346-353. [DOI: 10.1016/j.jelectrocard.2017.10.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2017] [Indexed: 11/17/2022]
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41
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Yin D, Chen M, Yang N, Wu AZ, Xu D, Tsai WC, Yuan Y, Tian Z, Chan YH, Shen C, Chen Z, Lin SF, Weiss JN, Chen PS, Everett TH. Role of apamin-sensitive small conductance calcium-activated potassium currents in long-term cardiac memory in rabbits. Heart Rhythm 2018; 15:761-769. [PMID: 29325977 DOI: 10.1016/j.hrthm.2018.01.016] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/05/2017] [Indexed: 12/13/2022]
Abstract
BACKGROUND Apamin-sensitive small conductance calcium-activated K current (IKAS) is up-regulated during ventricular pacing and masks short-term cardiac memory (CM). OBJECTIVE The purpose of this study was to determine the role of IKAS in long-term CM. METHODS CM was created with 3-5 weeks of ventricular pacing and defined by a flat or inverted T wave off pacing. Epicardial optical mapping was performed in both paced and normal ventricles. Action potential duration (APD80) was determined during right atrial pacing. Ventricular stability was tested before and after IKAS blockade. Four paced hearts and 4 normal hearts were used for western blotting and histology. RESULTS There were no significant differences in either echocardiographic parameters or fibrosis levels between groups. Apamin induced more APD80 prolongation in CM than in normal ventricles (mean [95% confidence interval]: 9.6% [8.8%-10.5%] vs 3.1% [1.9%-4.3%]; P <.001). Apamin significantly lengthened APD80 in the CM model at late activation sites, indicating significant IKAS up-regulation at those sites. The CM model also had altered Ca2+ handling, with the 50% Ca2+ transient duration and amplitude increased at distal sites compared to a proximal site (near the pacing site). After apamin, the CM model had increased ventricular fibrillation (VF) inducibility (paced vs control: 33/40 (82.5%) vs 7/20 (35%); P <.001) and longer VF durations (124 vs 26 seconds; P <.001). CONCLUSION Chronic ventricular pacing increases Ca2+ transients at late activation sites, which activates IKAS to maintain repolarization reserve. IKAS blockade increases VF vulnerability in chronically paced rabbit ventricles.
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Affiliation(s)
- Dechun Yin
- Krannert Institute of Cardiology and Division of Cardiology, Department of Medicine, Indiana University School of Medicine, Indianapolis, Indiana; Department of Cardiology, First Affiliated Hospital of Harbin Medical University, Harbin, China
| | - Mu Chen
- Department of Cardiology, Xinhua Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - Na Yang
- Krannert Institute of Cardiology and Division of Cardiology, Department of Medicine, Indiana University School of Medicine, Indianapolis, Indiana; Department of Gynecological and Obstetric Ultrasound, First Affiliated Hospital of Harbin Medical University, Harbin, China
| | - Adonis Z Wu
- Krannert Institute of Cardiology and Division of Cardiology, Department of Medicine, Indiana University School of Medicine, Indianapolis, Indiana; Institute of Biomedical Engineering, National Chiao-Tung University, Hsin-Chu, Taiwan
| | - Dongzhu Xu
- Krannert Institute of Cardiology and Division of Cardiology, Department of Medicine, Indiana University School of Medicine, Indianapolis, Indiana; Department of Cardiology, Faculty of Medicine, University of Tsukuba, Tsukuba, Japan
| | - Wei-Chung Tsai
- Division of Cardiology, Department of Internal Medicine, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung, Taiwan
| | - Yuan Yuan
- Department of Cardiothoracic Surgery, Xinhua Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - Zhipeng Tian
- Krannert Institute of Cardiology and Division of Cardiology, Department of Medicine, Indiana University School of Medicine, Indianapolis, Indiana; Department of Cardiology, Central Hospital Affiliated to Shenyang Medical College, Shenyang, Liaoning, China
| | - Yi-Hsin Chan
- Krannert Institute of Cardiology and Division of Cardiology, Department of Medicine, Indiana University School of Medicine, Indianapolis, Indiana; Division of Cardiology, Department of Internal Medicine, Chang Gung Memorial Hospital, Chang Gung University College of Medicine, Linkou, Taoyuan, Taiwan
| | - Changyu Shen
- Richard and Susan Smith Center for Outcomes Research in Cardiology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts
| | - Zhenhui Chen
- Krannert Institute of Cardiology and Division of Cardiology, Department of Medicine, Indiana University School of Medicine, Indianapolis, Indiana
| | - Shien-Fong Lin
- Institute of Biomedical Engineering, National Chiao-Tung University, Hsin-Chu, Taiwan
| | - James N Weiss
- Departments of Medicine and Physiology, University of California, Los Angeles, California
| | - Peng-Sheng Chen
- Krannert Institute of Cardiology and Division of Cardiology, Department of Medicine, Indiana University School of Medicine, Indianapolis, Indiana
| | - Thomas H Everett
- Krannert Institute of Cardiology and Division of Cardiology, Department of Medicine, Indiana University School of Medicine, Indianapolis, Indiana.
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Affiliation(s)
- O Gautschi
- Department of Internal Medicine, University Hospital, Bern
| | - B Naegeli
- Division of Cardiology, Department of Internal Medicine, Triemli Hospital, Zürich, Switzerland
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Danon A, Shurrab M. Alternating trifascicular block and cardiac memory. J Electrocardiol 2017; 50:966-968. [PMID: 28802655 DOI: 10.1016/j.jelectrocard.2017.07.006] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2017] [Indexed: 10/19/2022]
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Michowitz Y, Tovia-Brodie O, Heusler I, Sabbag A, Rahkovich M, Shmueli H, Glick A, Belhassen B. Differentiating the QRS Morphology of Posterior Fascicular Ventricular Tachycardia From Right Bundle Branch Block and Left Anterior Hemiblock Aberrancy. Circ Arrhythm Electrophysiol 2017; 10:CIRCEP.117.005074. [DOI: 10.1161/circep.117.005074] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/23/2017] [Accepted: 04/28/2017] [Indexed: 11/16/2022]
Affiliation(s)
- Yoav Michowitz
- From the Department of Cardiology, Tel Aviv Sourasky Medical Center, Israel (Y.M., O.T.-B., I.H., M.R., H.S., A.G., B.B.); Department of Cardiology, Sheba Medical Center, Israel (A.S.); and Department of Cardiology, Sackler Faculty of Medicine, Tel Aviv University, Israel (Y.M., O.T.-B., I.H., A.S., M.R., H.S., A.G., B.B.)
| | - Oholi Tovia-Brodie
- From the Department of Cardiology, Tel Aviv Sourasky Medical Center, Israel (Y.M., O.T.-B., I.H., M.R., H.S., A.G., B.B.); Department of Cardiology, Sheba Medical Center, Israel (A.S.); and Department of Cardiology, Sackler Faculty of Medicine, Tel Aviv University, Israel (Y.M., O.T.-B., I.H., A.S., M.R., H.S., A.G., B.B.)
| | - Ishai Heusler
- From the Department of Cardiology, Tel Aviv Sourasky Medical Center, Israel (Y.M., O.T.-B., I.H., M.R., H.S., A.G., B.B.); Department of Cardiology, Sheba Medical Center, Israel (A.S.); and Department of Cardiology, Sackler Faculty of Medicine, Tel Aviv University, Israel (Y.M., O.T.-B., I.H., A.S., M.R., H.S., A.G., B.B.)
| | - Avi Sabbag
- From the Department of Cardiology, Tel Aviv Sourasky Medical Center, Israel (Y.M., O.T.-B., I.H., M.R., H.S., A.G., B.B.); Department of Cardiology, Sheba Medical Center, Israel (A.S.); and Department of Cardiology, Sackler Faculty of Medicine, Tel Aviv University, Israel (Y.M., O.T.-B., I.H., A.S., M.R., H.S., A.G., B.B.)
| | - Michael Rahkovich
- From the Department of Cardiology, Tel Aviv Sourasky Medical Center, Israel (Y.M., O.T.-B., I.H., M.R., H.S., A.G., B.B.); Department of Cardiology, Sheba Medical Center, Israel (A.S.); and Department of Cardiology, Sackler Faculty of Medicine, Tel Aviv University, Israel (Y.M., O.T.-B., I.H., A.S., M.R., H.S., A.G., B.B.)
| | - Hezzy Shmueli
- From the Department of Cardiology, Tel Aviv Sourasky Medical Center, Israel (Y.M., O.T.-B., I.H., M.R., H.S., A.G., B.B.); Department of Cardiology, Sheba Medical Center, Israel (A.S.); and Department of Cardiology, Sackler Faculty of Medicine, Tel Aviv University, Israel (Y.M., O.T.-B., I.H., A.S., M.R., H.S., A.G., B.B.)
| | - Aharon Glick
- From the Department of Cardiology, Tel Aviv Sourasky Medical Center, Israel (Y.M., O.T.-B., I.H., M.R., H.S., A.G., B.B.); Department of Cardiology, Sheba Medical Center, Israel (A.S.); and Department of Cardiology, Sackler Faculty of Medicine, Tel Aviv University, Israel (Y.M., O.T.-B., I.H., A.S., M.R., H.S., A.G., B.B.)
| | - Bernard Belhassen
- From the Department of Cardiology, Tel Aviv Sourasky Medical Center, Israel (Y.M., O.T.-B., I.H., M.R., H.S., A.G., B.B.); Department of Cardiology, Sheba Medical Center, Israel (A.S.); and Department of Cardiology, Sackler Faculty of Medicine, Tel Aviv University, Israel (Y.M., O.T.-B., I.H., A.S., M.R., H.S., A.G., B.B.)
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Garzón A, Grigoriev RO. Memory effects, transient growth, and wave breakup in a model of paced atrium. CHAOS (WOODBURY, N.Y.) 2017; 27:093917. [PMID: 28964113 DOI: 10.1063/1.4999601] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
The mechanisms underlying cardiac fibrillation have been investigated for over a century, but we are still finding surprising results that change our view of this phenomenon. The present study focuses on the transition from normal rhythm to spiral wave chaos associated with a gradual increase in the pacing rate. While some of our findings are consistent with existing experimental, numerical, and theoretical studies of this problem, one result appears to contradict the accepted picture. Specifically we show that, in a two-dimensional model of paced homogeneous atrial tissue, transition from discordant alternans to conduction block, wave breakup, reentry, and spiral wave chaos is associated with the transient growth of finite amplitude disturbances rather than a conventional instability. It is mathematically very similar to subcritical, or bypass, transition from laminar fluid flow to turbulence, which allows many of the tools developed in the context of fluid turbulence to be used for improving our understanding of cardiac arrhythmias.
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Affiliation(s)
- Alejandro Garzón
- Department of Mathematics, Universidad Sergio Arboleda, Bogotá 110221, Colombia
| | - Roman O Grigoriev
- School of Physics, Georgia Institute of Technology, Atlanta, Georgia 30332-0430, USA
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Maffessanti F, Wanten J, Potse M, Regoli F, Caputo ML, Conte G, Sürder D, Illner A, Krause R, Moccetti T, Auricchio A, Prinzen FW. The relation between local repolarization and T-wave morphology in heart failure patients. Int J Cardiol 2017; 241:270-276. [DOI: 10.1016/j.ijcard.2017.02.056] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/06/2016] [Accepted: 02/15/2017] [Indexed: 11/16/2022]
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di Matteo I, Crea P. Negative concordant T waves during paced ventricular rhythm: An honest enemy is better than a false friend. J Electrocardiol 2017; 50:507-509. [PMID: 28343654 DOI: 10.1016/j.jelectrocard.2017.03.006] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2017] [Indexed: 01/20/2023]
Affiliation(s)
- Irene di Matteo
- Interventional Cardiology Unit, De Gasperis CardioCenter -ASST Grande Ospedale Metropolitano Niguarda, Milan
| | - Pasquale Crea
- Cardiology Unit, Department of Clinical and Experimental Medicine, University of Messina.
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48
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Mathews J, Levin M. Gap junctional signaling in pattern regulation: Physiological network connectivity instructs growth and form. Dev Neurobiol 2017; 77:643-673. [PMID: 27265625 PMCID: PMC10478170 DOI: 10.1002/dneu.22405] [Citation(s) in RCA: 58] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2016] [Revised: 05/27/2016] [Accepted: 05/31/2016] [Indexed: 12/19/2022]
Abstract
Gap junctions (GJs) are aqueous channels that allow cells to communicate via physiological signals directly. The role of gap junctional connectivity in determining single-cell functions has long been recognized. However, GJs have another important role: the regulation of large-scale anatomical pattern. GJs are not only versatile computational elements that allow cells to control which small molecule signals they receive and emit, but also establish connectivity patterns within large groups of cells. By dynamically regulating the topology of bioelectric networks in vivo, GJs underlie the ability of many tissues to implement complex morphogenesis. Here, a review of recent data on patterning roles of GJs in growth of the zebrafish fin, the establishment of left-right patterning, the developmental dysregulation known as cancer, and the control of large-scale head-tail polarity, and head shape in planarian regeneration has been reported. A perspective in which GJs are not only molecular features functioning in single cells, but also enable global neural-like dynamics in non-neural somatic tissues has been proposed. This view suggests a rich program of future work which capitalizes on the rapid advances in the biophysics of GJs to exploit GJ-mediated global dynamics for applications in birth defects, regenerative medicine, and morphogenetic bioengineering. © 2016 Wiley Periodicals, Inc. Develop Neurobiol 77: 643-673, 2017.
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Affiliation(s)
- Juanita Mathews
- Department of Biology, Tufts Center for Regenerative and Developmental Biology, Tufts University, Medford, MA
| | - Michael Levin
- Department of Biology, Tufts Center for Regenerative and Developmental Biology, Tufts University, Medford, MA
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Affiliation(s)
- Nishant Verma
- From Division of Cardiology, Department of Medicine, Northwestern University, Feinberg School of Medicine, Chicago, IL.
| | - Bradley P Knight
- From Division of Cardiology, Department of Medicine, Northwestern University, Feinberg School of Medicine, Chicago, IL
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50
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Effect of Loss of Heart Rate Variability on T-Wave Heterogeneity and QT Variability in Heart Failure Patients: Implications in Ventricular Arrhythmogenesis. Cardiovasc Eng Technol 2017; 8:219-228. [DOI: 10.1007/s13239-017-0299-9] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/28/2016] [Accepted: 02/25/2017] [Indexed: 11/25/2022]
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