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Carrick RT, Ahamed H, Sung E, Maron MS, Madias C, Avula V, Studley R, Bao C, Bokhari N, Quintana E, Rajesh-Kannan R, Maron BJ, Wu KC, Rowin EJ. Identification of high-risk imaging features in hypertrophic cardiomyopathy using electrocardiography: A deep-learning approach. Heart Rhythm 2024:S1547-5271(24)00085-7. [PMID: 38280624 PMCID: PMC11272903 DOI: 10.1016/j.hrthm.2024.01.031] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/17/2023] [Revised: 01/05/2024] [Accepted: 01/21/2024] [Indexed: 01/29/2024]
Abstract
BACKGROUND Patients with hypertrophic cardiomyopathy (HCM) are at risk of sudden death, and individuals with ≥1 major risk markers are considered for primary prevention implantable cardioverter-defibrillators. Guidelines recommend cardiac magnetic resonance (CMR) imaging to identify high-risk imaging features. However, CMR imaging is resource intensive and is not widely accessible worldwide. OBJECTIVE The purpose of this study was to develop electrocardiogram (ECG) deep-learning (DL) models for the identification of patients with HCM and high-risk imaging features. METHODS Patients with HCM evaluated at Tufts Medical Center (N = 1930; Boston, MA) were used to develop ECG-DL models for the prediction of high-risk imaging features: systolic dysfunction, massive hypertrophy (≥30 mm), apical aneurysm, and extensive late gadolinium enhancement. ECG-DL models were externally validated in a cohort of patients with HCM from the Amrita Hospital HCM Center (N = 233; Kochi, India). RESULTS ECG-DL models reliably identified high-risk features (systolic dysfunction, massive hypertrophy, apical aneurysm, and extensive late gadolinium enhancement) during holdout testing (c-statistic 0.72, 0.83, 0.93, and 0.76) and external validation (c-statistic 0.71, 0.76, 0.91, and 0.68). A hypothetical screening strategy using echocardiography combined with ECG-DL-guided selective CMR use demonstrated a sensitivity of 97% for identifying patients with high-risk features while reducing the number of recommended CMRs by 61%. The negative predictive value with this screening strategy for the absence of high-risk features in patients without ECG-DL recommendation for CMR was 99.5%. CONCLUSION In HCM, novel ECG-DL models reliably identified patients with high-risk imaging features while offering the potential to reduce CMR testing requirements in underresourced areas.
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Affiliation(s)
- Richard T Carrick
- Johns Hopkins University School of Medicine, Heart and Vascular Institute, Baltimore, Maryland.
| | - Hisham Ahamed
- Amrita Institute of Medical Sciences and Research Centre, Amrita Hypertrophic Cardiomyopathy Center, Kochi, Kerala, India
| | - Eric Sung
- Johns Hopkins University School of Medicine, Heart and Vascular Institute, Baltimore, Maryland
| | - Martin S Maron
- Lahey Hospital and Medical Center, Hypertrophic Cardiomyopathy Center, Burlington, Massachusetts
| | | | - Vennela Avula
- Johns Hopkins University School of Medicine, Heart and Vascular Institute, Baltimore, Maryland
| | - Rachael Studley
- Tufts Medical Center, Cardiac Arrhythmia Center, Boston, Massachusetts
| | - Chen Bao
- Tufts Medical Center, Cardiac Arrhythmia Center, Boston, Massachusetts
| | - Nadia Bokhari
- Tufts Medical Center, Cardiac Arrhythmia Center, Boston, Massachusetts
| | - Erick Quintana
- Tufts Medical Center, Cardiac Arrhythmia Center, Boston, Massachusetts
| | - Ramiah Rajesh-Kannan
- Amrita Institute of Medical Sciences and Research Centre, Amrita Hypertrophic Cardiomyopathy Center, Kochi, Kerala, India
| | - Barry J Maron
- Lahey Hospital and Medical Center, Hypertrophic Cardiomyopathy Center, Burlington, Massachusetts
| | - Katherine C Wu
- Johns Hopkins University School of Medicine, Heart and Vascular Institute, Baltimore, Maryland
| | - Ethan J Rowin
- Lahey Hospital and Medical Center, Hypertrophic Cardiomyopathy Center, Burlington, Massachusetts
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Dores H, Toste A, Cardim N. Hypertrophic cardiomyopathy in patients with a normal electrocardiogram: A view from the east side of the Atlantic Ocean. Int J Cardiol 2023; 390:131260. [PMID: 37579849 DOI: 10.1016/j.ijcard.2023.131260] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/20/2023] [Revised: 07/30/2023] [Accepted: 08/10/2023] [Indexed: 08/16/2023]
Abstract
BACKGROUND Although the 12‑lead electrocardiogram (ECG) is abnormal in most patients with hypertrophic cardiomyopathy (HCM), some present normal ECG. This study aimed to analyse the baseline characteristics, clinical presentation and outcomes of HCM patients with normal ECG and to compare them with those with abnormal ECG. METHODS AND RESULTS Baseline characteristics, clinical presentation, data from complementary exams and clinical outcomes of 1070 consecutive patients included in the Portuguese Registry of HCM (Pro-HCM registry) were compared between two groups of patients: normal Vs. abnormal ECG. Among this population, 98 (9.2%) patients had normal ECG at presentation; they were significantly younger and had lower frequency of hypertension, symptoms at presentation, heart failure, angina, cardiac and non-cardiac diseases. ESC and AHA risk scores for Sudden Cardiac Death (SCD) were not significantly different between the two groups. Patients with normal ECG had higher prevalence of family history of SCD and lower degree of left ventricular (LV) hypertrophy, LV systolic dysfunction, LV outflow tract obstruction and myocardial fibrosis. The combined endpoint of cardiac death, SCD, cardiac arrest, appropriate ICD shocks or evolution to systolic dysfunction, during a mean follow-up of 5 years was significantly less frequent in patients with normal ECG (2.1% Vs. 6.5%; p = 0.043). CONCLUSIONS A normal ECG is not a marker of an overall benign profile in HCM patients. Though a normal ECG at presentation is associated with a less severe phenotype and a lower probability of evolution to heart failure at 5-years, this finding did not show a protective effect in other clinical outcomes.
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Affiliation(s)
- Hélder Dores
- Hospital da Luz, Lisbon, Portugal; CHRC, NOVA Medical School, Lisbon, Portugal; NOVA Medical School, Lisbon, Portugal.
| | - Alexandra Toste
- Hospital da Luz, Lisbon, Portugal; NOVA Medical School, Lisbon, Portugal
| | - Nuno Cardim
- NOVA Medical School, Lisbon, Portugal; Hospital CUF Descobertas, Lisbon, Portugal
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Zhang N, Cheng S, Niu H, Gu M, Peng H, Sun Z, Liu X, Deng Y, Chen X, Hua W. Association of QTc Interval and V4-S Wave With Appropriate ICD Therapy in Hypertrophic Cardiomyopathy. Front Cardiovasc Med 2022; 9:882662. [PMID: 35647065 PMCID: PMC9133535 DOI: 10.3389/fcvm.2022.882662] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2022] [Accepted: 04/14/2022] [Indexed: 11/23/2022] Open
Abstract
Background Ventricular arrhythmias in patients with hypertrophic cardiomyopathy (HCM) may lead to sudden cardiac death (SCD). We aimed to investigate the relationship between electrocardiogram (ECG) indicators and the risk of appropriate implantable cardioverter-defibrillator (ICD) therapy in HCM. Methods The HCM patients receiving ICD implantation were enrolled consecutively. QT interval correction (QTc) was calculated using Bazett's formula. Long or deep S wave in V4 lead was defined as duration time >50 ms and/or voltage amplitude >0.6 mV. The endpoint in our study was at least one ICD appropriate therapy triggered by ventricular tachyarrhythmia (VT) or ventricular fibrillation (VF), including anti-tachyarrhythmia pacing (ATP) and electrical shock. Results A total of 149 patients with HCM (mean age 53 ± 14 years, male 69.8%) were studied. Appropriate ICD therapies occurred in 47 patients (31.5%) during a median follow-up of 2.9 years. Cox regression analysis showed that long or deep S wave in V4 lead [hazard ratio (HR) 1.955, 95% confidence interval (CI) 1.017–3.759, P = 0.045] and QTc interval (HR 1.014, 95% CI 1.008–1.021, P < 0.001) were independent risk factors for appropriate ICD therapy. The ROC showed that the optimal cut-off point value for the QTc interval to predict the appropriate ICD therapy was 464 ms, and the AUC was 0.658 (95% CI 0.544–0.762, P = 0.002). The AUC for S wave anomalies in V4 lead was 0.608 (95% CI 0.511–0.706, P = 0.034). We developed a new model that combined the QTc interval and S wave anomalies in V4 lead based on four patient groups. Patients with QTc ≥464 ms and long or deep V4-S wave had the highest risk of developing appropriate ICD therapy (log-rank P < 0.0001). After adding QTc interval and V4-S wave anomalies into the HCM-risk-SCD model, the prediction effect of the new model was significantly improved, and the NRI was 0.302. Conclusions In this HCM cohort, QTc and S wave anomalies in V4 lead were found to be significant and strong predictors of the risk of appropriate ICD therapy. Patients with QTc ≥464 ms and long or deep S wave had the highest risk. After QTc interval and V4-S wave anomalies adding to the HCM-risk-SCD model, the prediction effect is significantly improved.
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Affiliation(s)
- Nixiao Zhang
- Department of Cardiology, Cardiovascular Center, Beijing Friendship Hospital, Capital Medical University, Beijing, China
- Cardiac Arrhythmia Center, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Sijing Cheng
- Cardiac Arrhythmia Center, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Hongxia Niu
- Cardiac Arrhythmia Center, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Min Gu
- Cardiac Arrhythmia Center, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Hui Peng
- Department of Cardiology, Cardiovascular Center, Beijing Friendship Hospital, Capital Medical University, Beijing, China
- Hui Peng
| | - Zhijun Sun
- Department of Cardiology, Cardiovascular Center, Beijing Friendship Hospital, Capital Medical University, Beijing, China
| | - Xi Liu
- Cardiac Arrhythmia Center, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Yu Deng
- Cardiac Arrhythmia Center, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Xuhua Chen
- Cardiac Arrhythmia Center, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Wei Hua
- Cardiac Arrhythmia Center, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
- *Correspondence: Wei Hua
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Sherrid MV, Massera D. Risk Stratification and Hypertrophic Cardiomyopathy Subtypes. J Am Coll Cardiol 2020; 74:2346-2349. [PMID: 31699274 DOI: 10.1016/j.jacc.2019.09.020] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/29/2019] [Accepted: 09/03/2019] [Indexed: 11/16/2022]
Affiliation(s)
- Mark V Sherrid
- Hypertrophic Cardiomyopathy Program, Leon Charney Division of Cardiology, Department of Medicine, New York University School of Medicine, New York, New York.
| | - Daniele Massera
- Hypertrophic Cardiomyopathy Program, Leon Charney Division of Cardiology, Department of Medicine, New York University School of Medicine, New York, New York
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Lyon A, Mincholé A, Bueno-Orovio A, Rodriguez B. Improving the clinical understanding of hypertrophic cardiomyopathy by combining patient data, machine learning and computer simulations: A case study. Morphologie 2019; 103:169-179. [PMID: 31570308 PMCID: PMC6913520 DOI: 10.1016/j.morpho.2019.09.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2019] [Accepted: 09/10/2019] [Indexed: 01/02/2023]
Abstract
In this paper, we present how, by combining electrocardiogram and imaging data, machine learning and high performance computing simulations, we identified four phenotypes in hypertrophic cardiomyopathy (HCM), with differences in arrhythmic risk, and provided two distinct possible mechanisms that may explain the heterogeneity of HCM manifestation. This led to a better HCM patient stratification and understanding of the underlying disease mechanisms, providing a step further towards tailored HCM patient management and treatment.
Most patients with hypertrophic cardiomyopathy (HCM), the most common genetic cardiac disease, remain asymptomatic, but others may suffer from sudden cardiac death. A better identification of those patients at risk, together with a better understanding of the mechanisms leading to arrhythmia, are crucial to target high-risk patients and provide them with appropriate treatment. However, this currently remains a challenge. In this paper, we present a successful example of implementing computational techniques for clinically-relevant applications. By combining electrocardiogram and imaging data, machine learning and high performance computing simulations, we identified four phenotypes in HCM, with differences in arrhythmic risk, and provided two distinct possible mechanisms that may explain the heterogeneity of HCM manifestation. This led to a better HCM patient stratification and understanding of the underlying disease mechanisms, providing a step further towards tailored HCM patient management and treatment.
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Affiliation(s)
- A Lyon
- Department of Computer Science, University of Oxford, Oxford, United Kingdom; Cardiovascular Research Institute Maastricht (CARIM), Maastricht University, Maastricht, Netherlands
| | - A Mincholé
- Department of Computer Science, University of Oxford, Oxford, United Kingdom
| | - A Bueno-Orovio
- Department of Computer Science, University of Oxford, Oxford, United Kingdom
| | - B Rodriguez
- Department of Computer Science, University of Oxford, Oxford, United Kingdom.
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Finocchiaro G, Sheikh N, Biagini E, Papadakis M, Maurizi N, Sinagra G, Pelliccia A, Rapezzi C, Sharma S, Olivotto I. The electrocardiogram in the diagnosis and management of patients with hypertrophic cardiomyopathy. Heart Rhythm 2019; 17:142-151. [PMID: 31349064 DOI: 10.1016/j.hrthm.2019.07.019] [Citation(s) in RCA: 60] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/29/2019] [Indexed: 12/20/2022]
Abstract
In an era of rapid technological development and evolving diagnostic possibilities, the electrocardiogram (ECG) is living an authentic "renaissance" in myocardial diseases. To date, the ECG remains an irreplaceable first step when evaluating patients with hypertrophic cardiomyopathy (HCM) and an abnormal ECG may be the only manifestation of disease at an early stage. In some instances, specific electrical anomalies may differentiate HCM from phenocopies such as cardiac amyloidosis and glycogen storage diseases. The exponential growth in knowledge of the complexity of HCM has led to new challenges in terms of early identification of the disease, differential diagnosis, risk stratification, and development of targeted therapies. In this scenario, the apparently "old fashioned" ECG and the array of ECG-based techniques, ranging from Holter monitoring and loop recorders to exercise testing, are as contemporary as ever. In the present review, we discuss the current role of the ECG in the diagnosis and management of HCM, focusing on various clinical settings where its appropriate use and interpretation can make a difference.
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Affiliation(s)
| | - Nabeel Sheikh
- Cardiothoracic Centre, Guy's and St Thomas' Hospital, London, United Kingdom
| | - Elena Biagini
- Cardiology, Department of Experimental, Diagnostic and Specialty Medicine, Alma Mater Studiorum, University of Bologna, Bologna, Italy
| | - Michael Papadakis
- Cardiology Clinical and Academic Group, St George's, University of London, and St George's University Hospitals NHS Foundation Trust, London, United Kingdom
| | - Nicolo' Maurizi
- Cardiomyopathy Unit, Careggi University Hospital, Florence, Italy
| | | | | | - Claudio Rapezzi
- Cardiology, Department of Experimental, Diagnostic and Specialty Medicine, Alma Mater Studiorum, University of Bologna, Bologna, Italy
| | - Sanjay Sharma
- Cardiology Clinical and Academic Group, St George's, University of London, and St George's University Hospitals NHS Foundation Trust, London, United Kingdom
| | - Iacopo Olivotto
- Cardiomyopathy Unit, Careggi University Hospital, Florence, Italy
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7
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Lyon A, Bueno-Orovio A, Zacur E, Ariga R, Grau V, Neubauer S, Watkins H, Rodriguez B, Mincholé A. Electrocardiogram phenotypes in hypertrophic cardiomyopathy caused by distinct mechanisms: apico-basal repolarization gradients vs. Purkinje-myocardial coupling abnormalities. Europace 2018; 20:iii102-iii112. [PMID: 30476051 PMCID: PMC6251182 DOI: 10.1093/europace/euy226] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2018] [Accepted: 09/27/2018] [Indexed: 12/13/2022] Open
Abstract
AIMS To identify key structural and electrophysiological features explaining distinct electrocardiogram (ECG) phenotypes in hypertrophic cardiomyopathy (HCM). METHODS AND RESULTS Human heart-torso anatomical models were constructed from cardiac magnetic resonance (CMR) images of HCM patients, representative of ECG phenotypes identified previously. High performance computing simulations using bidomain models were conducted to dissect key features explaining the ECG phenotypes with increased HCM Risk-SCD scores, namely Group 1A, characterized by normal QRS but inverted T waves laterally and coexistence of apical and septal hypertrophy; and Group 3 with marked QRS abnormalities (deep and wide S waves laterally) and septal hypertrophy. Hypertrophic cardiomyopathy abnormalities characterized from CMR, such as hypertrophy, tissue microstructure alterations, abnormal conduction system, and ionic remodelling, were selectively included to assess their influence on ECG morphology. Electrocardiogram abnormalities could not be explained by increased wall thickness nor by local conduction abnormalities associated with fibre disarray or fibrosis. Inverted T wave with normal QRS (Group 1A) was obtained with increased apico-basal repolarization gradient caused by ionic remodelling in septum and apex. Lateral QRS abnormalities (Group 3) were only recovered with abnormal Purkinje-myocardium coupling. CONCLUSION Two ECG-based HCM phenotypes are explained by distinct mechanisms: ionic remodelling and action potential prolongation in hypertrophied apical and septal areas lead to T wave inversion with normal QRS complexes, whereas abnormal Purkinje-myocardial coupling causes abnormal QRS morphology in V4-V6. These findings have potential implications for patients' management as they point towards different arrhythmia mechanisms in different phenotypes.
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Affiliation(s)
- Aurore Lyon
- Department of Computer Science, University of Oxford, Wolfson Building, Parks Rd, Oxford, UK
| | - Alfonso Bueno-Orovio
- Department of Computer Science, University of Oxford, Wolfson Building, Parks Rd, Oxford, UK
| | - Ernesto Zacur
- Institute of Biomedical Engineering (IBME), Department of Engineering Science, University of Oxford, Oxford, UK
| | - Rina Ariga
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, UK
| | - Vicente Grau
- Institute of Biomedical Engineering (IBME), Department of Engineering Science, University of Oxford, Oxford, UK
| | - Stefan Neubauer
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, UK
| | - Hugh Watkins
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, UK
| | - Blanca Rodriguez
- Department of Computer Science, University of Oxford, Wolfson Building, Parks Rd, Oxford, UK
- Corresponding author. Tel: +44 1865 610806; fax: 00441865273839. E-mail address:
| | - Ana Mincholé
- Department of Computer Science, University of Oxford, Wolfson Building, Parks Rd, Oxford, UK
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Adhyapak SM, Parachuri VR. Electrical storms in patients with hypertrophic cardiomyopathy: Do we have a solution? J Thorac Cardiovasc Surg 2018; 156:709-710. [PMID: 30011760 DOI: 10.1016/j.jtcvs.2017.12.040] [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: 11/24/2017] [Accepted: 12/07/2017] [Indexed: 10/28/2022]
Affiliation(s)
| | - V Rao Parachuri
- Department of Cardiothoracic Surgery, Narayana Hrudayalaya Institute of Medical Sciences, Bangalore, India
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Lyon A, Ariga R, Mincholé A, Mahmod M, Ormondroyd E, Laguna P, de Freitas N, Neubauer S, Watkins H, Rodriguez B. Distinct ECG Phenotypes Identified in Hypertrophic Cardiomyopathy Using Machine Learning Associate With Arrhythmic Risk Markers. Front Physiol 2018; 9:213. [PMID: 29593570 PMCID: PMC5859357 DOI: 10.3389/fphys.2018.00213] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2017] [Accepted: 02/26/2018] [Indexed: 12/24/2022] Open
Abstract
Aims: Ventricular arrhythmia triggers sudden cardiac death (SCD) in hypertrophic cardiomyopathy (HCM), yet electrophysiological biomarkers are not used for risk stratification. Our aim was to identify distinct HCM phenotypes based on ECG computational analysis, and characterize differences in clinical risk factors and anatomical differences using cardiac magnetic resonance (CMR) imaging. Methods: High-fidelity 12-lead Holter ECGs from 85 HCM patients and 38 healthy volunteers were analyzed using mathematical modeling and computational clustering to identify phenotypic subgroups. Clinical features and the extent and distribution of hypertrophy assessed by CMR were evaluated in the subgroups. Results: QRS morphology alone was crucial to identify three HCM phenotypes with very distinct QRS patterns. Group 1 (n = 44) showed normal QRS morphology, Group 2 (n = 19) showed short R and deep S waves in V4, and Group 3 (n = 22) exhibited short R and long S waves in V4-6, and left QRS axis deviation. However, no differences in arrhythmic risk or distribution of hypertrophy were observed between these groups. Including T wave biomarkers in the clustering, four HCM phenotypes were identified: Group 1A (n = 20), with primary repolarization abnormalities showing normal QRS yet inverted T waves, Group 1B (n = 24), with normal QRS morphology and upright T waves, and Group 2 and Group 3 remaining as before, with upright T waves. Group 1A patients, with normal QRS and inverted T wave, showed increased HCM Risk-SCD scores (1A: 4.0%, 1B: 1.8%, 2: 2.1%, 3: 2.5%, p = 0.0001), and a predominance of coexisting septal and apical hypertrophy (p < 0.0001). HCM patients in Groups 2 and 3 exhibited predominantly septal hypertrophy (85 and 90%, respectively). Conclusion: HCM patients were classified in four subgroups with distinct ECG features. Patients with primary T wave inversion not secondary to QRS abnormalities had increased HCM Risk-SCD scores and coexisting septal and apical hypertrophy, suggesting that primary T wave inversion may increase SCD risk in HCM, rather than T wave inversion secondary to depolarization abnormalities. Computational ECG phenotyping provides insight into the underlying processes captured by the ECG and has the potential to be a novel and independent factor for risk stratification.
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Affiliation(s)
- Aurore Lyon
- Department of Computer Science, University of Oxford, Oxford, United Kingdom
| | - Rina Ariga
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Ana Mincholé
- Department of Computer Science, University of Oxford, Oxford, United Kingdom
| | - Masliza Mahmod
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Elizabeth Ormondroyd
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Pablo Laguna
- Biomedical Signal Interpretation & Computational Simulation Group, CIBER-BBN, University of Zaragoza, Zaragoza, Spain
| | - Nando de Freitas
- Department of Computer Science, University of Oxford, Oxford, United Kingdom
| | - Stefan Neubauer
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Hugh Watkins
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Blanca Rodriguez
- Department of Computer Science, University of Oxford, Oxford, United Kingdom
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Magrì D, Santolamazza C, Limite L, Mastromarino V, Casenghi M, Orlando P, Pagannone E, Musumeci MB, Maruotti A, Ricotta A, Oliviero G, Piccirillo G, Volpe M, Autore C. QT spatial dispersion and sudden cardiac death in hypertrophic cardiomyopathy: Time for reappraisal. J Cardiol 2017; 70:310-315. [PMID: 28341542 DOI: 10.1016/j.jjcc.2017.01.006] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/13/2016] [Revised: 01/17/2017] [Accepted: 01/27/2017] [Indexed: 01/18/2023]
Abstract
BACKGROUND The 12-lead surface electrocardiographic (ECG) analysis is able to provide independent predictors of prognosis in several cardiovascular settings, including hypertrophic cardiomyopathy (HCM). The present single-center study investigated the possible ability of several ECG-derived variables in stratifying sudden cardiac death (SCD) risk and, possibly, in improving the accuracy of the 2014 European Society of Cardiology guidelines. METHODS A total of 221 consecutive HCM outpatients were recruited and prospectively followed. All of them underwent a full clinical and instrumental examination, including a 12-lead surface ECG to calculate the dispersion for the following intervals: QRS, Q-Tend (QT), Q-Tpeak (QTp), Tpeak-Tend (TpTe), J-Tpeak (JTp), and J-Tend (JT). The study composite end-point was SCD, aborted SCD, and appropriate implantable cardioverter defibrillator (ICD) interventions. RESULTS During a median follow-up of 4.4 years (25th-75th interquartile range: 2.4-9.4 years), 23 patients reached the end-point at 5-years (3 SCD, 3 aborted SCD, 17 appropriate ICD interventions). At multivariate analysis, the spatial QT dispersion corrected according to Bazett's formula (QTcd) remains independently associated to the study endpoint over the HCM Risk-SCD score (C-index 0.737). A QTcd cut-off value of 93ms showed the best accuracy in predicting the SCD endpoint within the entire HCM study cohort (sensitivity 56%, specificity 75%, positive predictive value 22%, negative predictive value 97%). CONCLUSION Our data suggest that the QTcd might be helpful in SCD risk stratification, particularly in those HCM categories classified at low-intermediate SCD risk according to the contemporary guidelines.
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Affiliation(s)
- Damiano Magrì
- Department of Clinical and Molecular Medicine, "Sapienza" University, Rome, Italy.
| | | | - Luca Limite
- Department of Clinical and Molecular Medicine, "Sapienza" University, Rome, Italy
| | | | - Matteo Casenghi
- Department of Clinical and Molecular Medicine, "Sapienza" University, Rome, Italy
| | - Paola Orlando
- Department of Clinical and Molecular Medicine, "Sapienza" University, Rome, Italy
| | - Erika Pagannone
- Department of Clinical and Molecular Medicine, "Sapienza" University, Rome, Italy
| | | | - Antonello Maruotti
- Department of Scienze Economiche, Politiche e delle Lingue Moderne, Libera Università SS Maria Assunta, Rome, Italy; Centre for Innovation and Leadership in Health Sciences, University of Southampton, Southampton, UK
| | - Agnese Ricotta
- Department of Clinical and Molecular Medicine, "Sapienza" University, Rome, Italy
| | - Giada Oliviero
- Department of Cardiovascular Sciences, University of Insubria, Varese, Italy
| | - Gianfranco Piccirillo
- Department of Cardiovascular, Respiratory, Anesthesiological, Nephrologic and Geriatrics Sciences, "Sapienza" University, Rome, Italy
| | - Massimo Volpe
- Department of Clinical and Molecular Medicine, "Sapienza" University, Rome, Italy; IRCCS, Neuromed, Pozzilli (IS), Italy
| | - Camillo Autore
- Department of Clinical and Molecular Medicine, "Sapienza" University, Rome, Italy
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FRANCIA PIETRO, ADDUCI CARMEN, PALANO FRANCESCA, SEMPRINI LORENZO, SERDOZ ANDREA, MONTESANTI DALMA, SANTINI DARIA, MUSUMECI BEATRICE, SALVATI ADRIANO, VOLPE MASSIMO, AUTORE CAMILLO. Eligibility for the Subcutaneous Implantable Cardioverter-Defibrillator in Patients With Hypertrophic Cardiomyopathy. J Cardiovasc Electrophysiol 2015; 26:893-899. [DOI: 10.1111/jce.12714] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/23/2015] [Revised: 04/21/2015] [Accepted: 04/24/2015] [Indexed: 12/22/2022]
Affiliation(s)
- PIETRO FRANCIA
- Division of Cardiology; Department of Clinical and Molecular Medicine; St. Andrea Hospital; Sapienza University; Rome Italy
| | - CARMEN ADDUCI
- Division of Cardiology; Department of Clinical and Molecular Medicine; St. Andrea Hospital; Sapienza University; Rome Italy
| | - FRANCESCA PALANO
- Division of Cardiology; Department of Clinical and Molecular Medicine; St. Andrea Hospital; Sapienza University; Rome Italy
| | - LORENZO SEMPRINI
- Division of Cardiology; Department of Clinical and Molecular Medicine; St. Andrea Hospital; Sapienza University; Rome Italy
| | - ANDREA SERDOZ
- Division of Cardiology; Department of Clinical and Molecular Medicine; St. Andrea Hospital; Sapienza University; Rome Italy
| | - DALMA MONTESANTI
- Division of Cardiology; Department of Clinical and Molecular Medicine; St. Andrea Hospital; Sapienza University; Rome Italy
| | - DARIA SANTINI
- Division of Cardiology; Department of Clinical and Molecular Medicine; St. Andrea Hospital; Sapienza University; Rome Italy
| | - BEATRICE MUSUMECI
- Division of Cardiology; Department of Clinical and Molecular Medicine; St. Andrea Hospital; Sapienza University; Rome Italy
| | - ADRIANO SALVATI
- Division of Cardiology; Department of Clinical and Molecular Medicine; St. Andrea Hospital; Sapienza University; Rome Italy
| | - MASSIMO VOLPE
- Division of Cardiology; Department of Clinical and Molecular Medicine; St. Andrea Hospital; Sapienza University; Rome Italy
- IRCCS Neuromed; Pozzilli Isernia Italy
| | - CAMILLO AUTORE
- Division of Cardiology; Department of Clinical and Molecular Medicine; St. Andrea Hospital; Sapienza University; Rome Italy
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12
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Magrì D, Piccirillo G, Ricotta A, De Cecco CN, Mastromarino V, Serdoz A, Muscogiuri G, Gregori M, Casenghi M, Cauti FM, Oliviero G, Musumeci MB, Maruotti A, Autore C. Spatial QT Dispersion Predicts Nonsustained Ventricular Tachycardia and Correlates with Confined Systodiastolic Dysfunction in Hypertrophic Cardiomyopathy. Cardiology 2015; 131:122-9. [DOI: 10.1159/000377622] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/06/2014] [Accepted: 01/28/2015] [Indexed: 11/19/2022]
Abstract
Objectives: An increased dispersion of myocardial repolarization represents one of the mechanisms underlying the arrhythmic risk in hypertrophic cardiomyopathy (HCM). We investigated spatial myocardial repolarization dispersion indices in HCM patients with nonsustained ventricular tachycardia (NSVT) and, contextually, their main clinical determinants. Methods: Fifty-two well-matched HCM outpatients were categorized into two groups according to the presence or the absence of NSVT at 24-hour Holter electrocardiogram (ECG) monitoring. Each patient underwent a clinical examination, including Doppler echocardiogram integrated with tissue Doppler imaging, cardiac magnetic resonance, and 12-lead surface ECG to calculate the dispersion for the following intervals: QRS, Q-Tend (QTe), Q-Tpeak, Tpeak-Tend (TpTe), J-Tpeak, and J-Tend. Results: The NSVT group showed only QTe dispersion and TpTe dispersion values to be significantly higher than their counterparts. NSVT occurrence was independently predicted by late gadolinium enhancement presence (p = 0.021) and QTe Bazett dispersion (p = 0.030), the latter strongly associated with the myocardial performance index (MPI) obtained at the basal segment of the interventricular septum (p = 0.0004). Conclusion: Our data support QTe dispersion as an easy and noninvasive tool for identifying HCM patients with NSVT propensity. The strong relationship between QTe dispersion and MPI allows us to hypothesize an intriguing link between electrical instability and confined myocardial areas of systodiastolic dysfunction.
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13
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Debonnaire P, Katsanos S, Joyce E, VAN DEN Brink OVW, Atsma DE, Schalij MJ, Bax JJ, Delgado V, Marsan NA. QRS Fragmentation and QTc Duration Relate to Malignant Ventricular Tachyarrhythmias and Sudden Cardiac Death in Patients with Hypertrophic Cardiomyopathy. J Cardiovasc Electrophysiol 2015; 26:547-55. [PMID: 25648421 DOI: 10.1111/jce.12629] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/27/2014] [Revised: 01/19/2015] [Accepted: 01/27/2015] [Indexed: 10/24/2022]
Abstract
BACKGROUND QRS fragmentation (fQRS) and prolonged QTc interval on surface ECG are prognostic in various cardiomyopathies other than hypertrophic cardiomyopathy (HCM). The association between fQRS and prolonged QTc duration with occurrence of ventricular tachyarrhythmias or sudden cardiac death (VTA/SCD) in patients with HCM was explored. METHODS AND RESULTS One hundred and ninety-five clinical HCM patients were studied. QTc duration was derived applying Bazett's formula; fQRS was defined as presence of various RSR' patterns, R or S notching and/or >1 additional R wave in any non-aVR lead in patients without pacing or (in)complete bundle branch block. The endpoints comprised SCD, ECG documented sustained VTA (tachycardia or fibrillation) or appropriate implantable cardioverter defibrillator (ICD) therapies (antitachycardia pacing [ATP] or shock) for VTA in ICD recipients (n = 58 [30%]). QT prolonging drugs recipients were excluded. After a median follow-up of 5.7 years (IQR 2.7-9.1), 26 (13%) patients experienced VTA or SCD. Patients with fQRS in ≥3 territories (inferior, lateral, septal, and/or anterior) (p = 0.004) or QTc ≥460 ms (p = 0.009) had worse cumulative survival free of VTA/SCD than patients with fQRS in <3 territories or QTc <460 ms. fQRS in ≥3 territories (ß 4.5, p = 0.020, 95%CI 1.41-14.1) and QTc ≥460 ms (ß 2.7, p = 0.037, 95%CI 1.12-6.33) were independently associated with VTA/SCD. Likelihood ratio test indicated assessment of fQRS and QTc on top of conventional SCD risk factors provides incremental predictive value for VTA/SCD (p = 0.035). CONCLUSIONS Both fQRS in ≥3 territories and QTc duration are associated with VTA/SCD in HCM patients, independently of and incremental to conventional SCD risk factors.
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Affiliation(s)
- Philippe Debonnaire
- Leiden University Medical Centre, Department of Cardiology, Leiden, the Netherlands.,Sint-Jan Hospital Bruges, Department of Cardiology, Bruges, Belgium
| | - Spyridon Katsanos
- Leiden University Medical Centre, Department of Cardiology, Leiden, the Netherlands
| | - Emer Joyce
- Leiden University Medical Centre, Department of Cardiology, Leiden, the Netherlands
| | | | - Douwe E Atsma
- Leiden University Medical Centre, Department of Cardiology, Leiden, the Netherlands
| | - Martin J Schalij
- Leiden University Medical Centre, Department of Cardiology, Leiden, the Netherlands
| | - Jeroen J Bax
- Leiden University Medical Centre, Department of Cardiology, Leiden, the Netherlands
| | - Victoria Delgado
- Leiden University Medical Centre, Department of Cardiology, Leiden, the Netherlands
| | - Nina Ajmone Marsan
- Leiden University Medical Centre, Department of Cardiology, Leiden, the Netherlands
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14
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Zhang L, Mmagu O, Liu L, Li D, Fan Y, Baranchuk A, Kowey PR. Hypertrophic cardiomyopathy: Can the noninvasive diagnostic testing identify high risk patients? World J Cardiol 2014; 6:764-770. [PMID: 25228955 PMCID: PMC4163705 DOI: 10.4330/wjc.v6.i8.764] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/12/2014] [Revised: 03/25/2014] [Accepted: 05/29/2014] [Indexed: 02/06/2023] Open
Abstract
Hypertrophic cardiomyopathy (HCM) is the most common cause of sudden cardiac death (SCD) in the young, particularly among athletes. Identifying high risk individuals is very important for SCD prevention. The purpose of this review is to stress that noninvasive diagnostic testing is important for risk assessment. Extreme left ventricular hypertrophy and documented ventricular tachycardia and fibrillation increase the risk of SCD. Fragmented QRS and T wave inversion in multiple leads are more common in high risk patients. Cardiac magnetic resonance imaging provides complete visualization of the left ventricular chamber, allowing precise localization of the distribution of hypertrophy and measurement of wall thickness and cardiac mass. Moreover, with late gadolinium enhancement, patchy myocardial fibrosis within the area of hypertrophy can be detected, which is also helpful in risk stratification. Genetic testing is encouraged in all cases, especially in those with a family history of HCM and SCD.
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15
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Greater insulin resistance indicates decreased diurnal variation in the QT interval in patients with type 2 diabetes. Heart Vessels 2013; 29:256-62. [PMID: 23681273 DOI: 10.1007/s00380-013-0356-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/07/2012] [Accepted: 04/12/2013] [Indexed: 10/26/2022]
Abstract
Circadian variations in the QT interval (QT) and QT dispersion are decreased in patients with type 2 diabetes because of cardioneuropathy. Insulin resistance has been recently identified as an independent determinant of QT prolongation in normoglycemic women. However, the relationship between QT prolongation and the degree of insulin resistance as well as circadian variation remains unclear in diabetic patients. This study was designed to assess the relationship between insulin resistance and the circadian variation in QT measurements in patients with type 2 diabetes. In 14 patients with diabetes, QT, corrected QT (QTc), QT dispersion, QTc dispersion, and RR interval (RR) were analyzed using 12-lead Holter monitoring and commercial software. The degree of diurnal variation in each measurement was defined as the amplitude between the maximum and mean values on curves fitted using the mean cosinor method (A_QT, A_QTc, A_QT dispersion, A_QTc dispersion, and A_RR). The cosine curve was fitted to all measured values in each QT measurement and RR for 24 h. Insulin resistance (glucose infusion rate (GIR)) was measured using the euglycemic hyperinsulinemic glucose clamp method. The maximum QT, QTc, QT dispersion, and QTc dispersion were >450 ms. GIR was significantly correlated with A_QT only (r = 0.59, P < 0.05). GIR was not correlated with other variables, and was dependent only on the circadian variation in QT.
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16
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Femenía F, Arce M, Arrieta M, Baranchuk A. Surface fragmented QRS in a patient with hypertrophic cardiomyopathy and malignant arrhythmias: Is there an association? J Cardiovasc Dis Res 2012; 3:32-5. [PMID: 22346143 PMCID: PMC3271679 DOI: 10.4103/0975-3583.91602] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
An 18- year old woman with hypertrophic cardiomyopathy, aborted sudden cardiac death and implanted with an implantable cardioverter defibrillator (ICD), developed progressive fragmentation of her surface 12-lead electrocardiogram (ECG). During the follow-up, she presented with multiple appropriate ICD discharges. Here, we discuss the possible association between surface fragmented ECG and the risk of ventricular arrhythmias in patients with hypertrophic cardiomyopathy.
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Affiliation(s)
- Francisco Femenía
- Unidad de Arritmias. Departamento de Cardiología. Hospital Español de Mendoza. Argentina
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17
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Hutchings DC, Sankaranarayanan R, Venetucci L. Ventricular arrhythmias complicating hypertrophic cardiomyopathy. Br J Hosp Med (Lond) 2012; 73:502-8. [DOI: 10.12968/hmed.2012.73.9.502] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Hypertrophic cardiomyopathy is the most common genetic cardiovascular disorder and the leading cause of sudden cardiac death in the young. This article reviews the ventricular arrhythmias associated with hypertrophic cardiomyopathy, the difficulties in risk stratification, and current and future therapeutic strategies.
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Affiliation(s)
- David C Hutchings
- Department of Cardiac Physiology, University of Manchester, Manchester M13 9NT
| | - Rajiv Sankaranarayanan
- Electrophysiology and British Heart Foundation Clinical Research Fellow, University of Manchester, Manchester
| | - Luigi Venetucci
- British Heart Foundation Intermediate Clinical Fellow, University of Manchester, Manchester
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18
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Schinkel AF, Vriesendorp PA, Sijbrands EJ, Jordaens LJ, ten Cate FJ, Michels M. Outcome and Complications After Implantable Cardioverter Defibrillator Therapy in Hypertrophic Cardiomyopathy. Circ Heart Fail 2012; 5:552-9. [DOI: 10.1161/circheartfailure.112.969626] [Citation(s) in RCA: 132] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- Arend F.L. Schinkel
- From the Department of Cardiology, Thoraxcenter (A.F.L.S., P.A.V., L.J.L.M.J., F.J.T.C., M.M.) and Department of Internal Medicine, Section of Pharmacology, Vascular and Metabolic Diseases (A.F.L.S., E.J.G.S.), Erasmus MC, Rotterdam, The Netherlands
| | - Pieter A. Vriesendorp
- From the Department of Cardiology, Thoraxcenter (A.F.L.S., P.A.V., L.J.L.M.J., F.J.T.C., M.M.) and Department of Internal Medicine, Section of Pharmacology, Vascular and Metabolic Diseases (A.F.L.S., E.J.G.S.), Erasmus MC, Rotterdam, The Netherlands
| | - Eric J.G. Sijbrands
- From the Department of Cardiology, Thoraxcenter (A.F.L.S., P.A.V., L.J.L.M.J., F.J.T.C., M.M.) and Department of Internal Medicine, Section of Pharmacology, Vascular and Metabolic Diseases (A.F.L.S., E.J.G.S.), Erasmus MC, Rotterdam, The Netherlands
| | - Luc J.L.M. Jordaens
- From the Department of Cardiology, Thoraxcenter (A.F.L.S., P.A.V., L.J.L.M.J., F.J.T.C., M.M.) and Department of Internal Medicine, Section of Pharmacology, Vascular and Metabolic Diseases (A.F.L.S., E.J.G.S.), Erasmus MC, Rotterdam, The Netherlands
| | - Folkert J. ten Cate
- From the Department of Cardiology, Thoraxcenter (A.F.L.S., P.A.V., L.J.L.M.J., F.J.T.C., M.M.) and Department of Internal Medicine, Section of Pharmacology, Vascular and Metabolic Diseases (A.F.L.S., E.J.G.S.), Erasmus MC, Rotterdam, The Netherlands
| | - Michelle Michels
- From the Department of Cardiology, Thoraxcenter (A.F.L.S., P.A.V., L.J.L.M.J., F.J.T.C., M.M.) and Department of Internal Medicine, Section of Pharmacology, Vascular and Metabolic Diseases (A.F.L.S., E.J.G.S.), Erasmus MC, Rotterdam, The Netherlands
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Badran HM, Elnoamany MF, Soltan G, Ezat M, Elsedi M, Abdelfatah RA, Yacoub M. Relationship of mechanical dyssynchrony to QT interval prolongation in hypertrophic cardiomyopathy. Eur Heart J Cardiovasc Imaging 2011; 13:423-32. [DOI: 10.1093/ejechocard/jer290] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
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20
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GERSTENFELD EDWARDP. Hypertrophic Cardiomyopathy with Midcavitary Obstruction: Another Substrate for Ventricular Tachycardia? J Cardiovasc Electrophysiol 2010; 21:1000-1. [DOI: 10.1111/j.1540-8167.2010.01800.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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