1
|
Pukropski J, Baumann J, Jordan A, Bausch M, von Wrede R, Surges R. Short-term effects of transcutaneous auricular vagus nerve stimulation on T-wave alternans in people with focal epilepsy - An exploratory pilot study. Epilepsy Behav Rep 2024; 26:100657. [PMID: 38495402 PMCID: PMC10940126 DOI: 10.1016/j.ebr.2024.100657] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2023] [Revised: 03/04/2024] [Accepted: 03/04/2024] [Indexed: 03/19/2024] Open
Abstract
High levels of T-wave alternans (TWA) are linked to an increased risk of sudden cardiac death. People with epilepsy display elevated TWA levels that are decreased by chronic vagus nerve stimulation via implanted devices after 2-4 weeks or later. Our objective was to explore short-term effects of transcutaneous auricular vagus nerve stimulation (tVNS) on TWA. Five patients (3 female) with focal epilepsy undergoing video-EEG monitoring were included. TWA levels were determined using a one-channel modified lead I ECG via an open-source TWA-algorithm on two consecutive days, 1 h before, during and after tVNS via the left auricle. Data are given as mean ± SE. Mean TWA at baseline was 3.8 ± 0.4 µV and 3.0 ± 0.6 µV during stimulation on day 2. Stimulations on the second day were associated with TWA reductions by 22 ± 13 % that exceeded stimulation effects on the first day relative to baseline (p < 0.05). Linear mixed-models revealed effects of both stimulation (p < 0.05) and stimulation number (p < 0.005). Normalized TWA showed reproducible peak reductions at both days within 35 min after the initiation of tVNS (p < 0.05). Our observations suggest that tVNS has short-term effects on TWA, supporting the notion that vagus nerve stimulation has a beneficial impact on electrical cardiac properties.
Collapse
Affiliation(s)
| | - Jan Baumann
- Department of Epileptology, University Hospital Bonn, Germany
| | - Arthur Jordan
- Department of Epileptology, University Hospital Bonn, Germany
| | | | | | | |
Collapse
|
2
|
Duca ȘT, Badescu MC, Costache AD, Chetran A, Miftode RȘ, Tudorancea I, Mitu O, Afrăsânie I, Ciorap RG, Șerban IL, Pavăl DR, Dmour B, Cepoi MR, Costache-Enache II. Harmony in Chaos: Deciphering the Influence of Ischemic Cardiomyopathy and Non-Cardiac Comorbidities on Holter ECG Parameters in Chronic Heart Failure Patients: A Pilot Study. MEDICINA (KAUNAS, LITHUANIA) 2024; 60:342. [PMID: 38399629 PMCID: PMC10889994 DOI: 10.3390/medicina60020342] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/12/2024] [Revised: 02/06/2024] [Accepted: 02/17/2024] [Indexed: 02/25/2024]
Abstract
Background and Objective: In the landscape of heart failure, non-cardiac comorbidities represent a formidable challenge, imparting adverse prognostic implications. Holter ECG monitoring assumes a supplementary role in delineating myocardial susceptibility and autonomic nervous system dynamics. This study aims to explore the potential correlation between Holter ECG parameters and comorbidities in individuals with ischemic cardiomyopathy experiencing heart failure (HF), with a particular focus on the primary utility of these parameters as prognostic indicators. Materials and Methods: In this prospective inquiry, a cohort of 60 individuals diagnosed with heart failure underwent stratification into subgroups based on the presence of comorbidities, including diabetes, chronic kidney disease, obesity, or hyperuricemia. Upon admission, a thorough evaluation of all participants encompassed echocardiography, laboratory panel analysis, and 24 h Holter monitoring. Results: Significant associations were uncovered between diabetes and unconventional physiological indicators, specifically the Triangular index (p = 0.035) and deceleration capacity (p = 0.002). Pertaining to creatinine clearance, notable correlations surfaced with RMSSD (p = 0.026), PNN50 (p = 0.013), and high-frequency power (p = 0.026). An examination of uric acid levels and distinctive Holter ECG patterns unveiled statistical significance, particularly regarding the deceleration capacity (p = 0.045). Nevertheless, in the evaluation of the Body Mass Index, no statistically significant findings emerged concerning Holter ECG parameters. Conclusions: The identified statistical correlations between non-cardiac comorbidities and patterns elucidated in Holter ECG recordings underscore the heightened diagnostic utility of this investigative modality in the comprehensive evaluation of individuals grappling with HF. Furthermore, we underscore the critical importance of the thorough analysis of Holter ECG recordings, particularly with regard to subtle and emerging parameters that may be overlooked or insufficiently acknowledged.
Collapse
Affiliation(s)
- Ștefania-Teodora Duca
- Department of Internal Medicine I, Faculty of Medicine, University of Medicine and Pharmacy “Grigore T. Popa”, 700115 Iasi, Romania; (Ș.-T.D.); (A.C.); (R.Ș.M.); (O.M.); (I.A.); (B.D.); (M.-R.C.); (I.-I.C.-E.)
- Department of Cardiology, “St. Spiridon” Emergency County Hospital, 700111 Iasi, Romania;
| | - Minerva Codruta Badescu
- Department of Internal Medicine I, Faculty of Medicine, University of Medicine and Pharmacy “Grigore T. Popa”, 700115 Iasi, Romania; (Ș.-T.D.); (A.C.); (R.Ș.M.); (O.M.); (I.A.); (B.D.); (M.-R.C.); (I.-I.C.-E.)
- Department of III Internal Medicine Clinic, “St. Spiridon” Emergency County Hospital, 700111 Iasi, Romania
| | - Alexandru-Dan Costache
- Department of Internal Medicine I, Faculty of Medicine, University of Medicine and Pharmacy “Grigore T. Popa”, 700115 Iasi, Romania; (Ș.-T.D.); (A.C.); (R.Ș.M.); (O.M.); (I.A.); (B.D.); (M.-R.C.); (I.-I.C.-E.)
- Department of Cardiovascular Rehabilitation, Clinical Rehabilitation Hospital, 700661 Iasi, Romania
| | - Adriana Chetran
- Department of Internal Medicine I, Faculty of Medicine, University of Medicine and Pharmacy “Grigore T. Popa”, 700115 Iasi, Romania; (Ș.-T.D.); (A.C.); (R.Ș.M.); (O.M.); (I.A.); (B.D.); (M.-R.C.); (I.-I.C.-E.)
- Department of Cardiology, “St. Spiridon” Emergency County Hospital, 700111 Iasi, Romania;
| | - Radu Ștefan Miftode
- Department of Internal Medicine I, Faculty of Medicine, University of Medicine and Pharmacy “Grigore T. Popa”, 700115 Iasi, Romania; (Ș.-T.D.); (A.C.); (R.Ș.M.); (O.M.); (I.A.); (B.D.); (M.-R.C.); (I.-I.C.-E.)
- Department of Cardiology, “St. Spiridon” Emergency County Hospital, 700111 Iasi, Romania;
| | - Ionuț Tudorancea
- Department of Cardiology, “St. Spiridon” Emergency County Hospital, 700111 Iasi, Romania;
- Department of Morpho-Functional Science II-Physiology, University of Medicine and Pharmacy “Grigore T. Popa”, 700115 Iasi, Romania;
| | - Ovidiu Mitu
- Department of Internal Medicine I, Faculty of Medicine, University of Medicine and Pharmacy “Grigore T. Popa”, 700115 Iasi, Romania; (Ș.-T.D.); (A.C.); (R.Ș.M.); (O.M.); (I.A.); (B.D.); (M.-R.C.); (I.-I.C.-E.)
- Department of Cardiology, “St. Spiridon” Emergency County Hospital, 700111 Iasi, Romania;
| | - Irina Afrăsânie
- Department of Internal Medicine I, Faculty of Medicine, University of Medicine and Pharmacy “Grigore T. Popa”, 700115 Iasi, Romania; (Ș.-T.D.); (A.C.); (R.Ș.M.); (O.M.); (I.A.); (B.D.); (M.-R.C.); (I.-I.C.-E.)
- Department of Cardiology, “St. Spiridon” Emergency County Hospital, 700111 Iasi, Romania;
| | - Radu-George Ciorap
- Department of Biomedical Science, Faculty of Medical Bioengineering, University of Medicine and Pharmacy “Grigore T. Popa”, 700145 Iasi, Romania;
| | - Ionela-Lăcrămioara Șerban
- Department of Morpho-Functional Science II-Physiology, University of Medicine and Pharmacy “Grigore T. Popa”, 700115 Iasi, Romania;
| | - D. Robert Pavăl
- Faculty of Health Sciences and Sport, University of Stirling, Stirling FK9 4LA, UK;
| | - Bianca Dmour
- Department of Internal Medicine I, Faculty of Medicine, University of Medicine and Pharmacy “Grigore T. Popa”, 700115 Iasi, Romania; (Ș.-T.D.); (A.C.); (R.Ș.M.); (O.M.); (I.A.); (B.D.); (M.-R.C.); (I.-I.C.-E.)
| | - Maria-Ruxandra Cepoi
- Department of Internal Medicine I, Faculty of Medicine, University of Medicine and Pharmacy “Grigore T. Popa”, 700115 Iasi, Romania; (Ș.-T.D.); (A.C.); (R.Ș.M.); (O.M.); (I.A.); (B.D.); (M.-R.C.); (I.-I.C.-E.)
| | - Irina-Iuliana Costache-Enache
- Department of Internal Medicine I, Faculty of Medicine, University of Medicine and Pharmacy “Grigore T. Popa”, 700115 Iasi, Romania; (Ș.-T.D.); (A.C.); (R.Ș.M.); (O.M.); (I.A.); (B.D.); (M.-R.C.); (I.-I.C.-E.)
- Department of Cardiology, “St. Spiridon” Emergency County Hospital, 700111 Iasi, Romania;
| |
Collapse
|
3
|
Martin-Yebra A, Sornmo L, Laguna P. QT interval Adaptation to Heart Rate Changes in Atrial Fibrillation as a Predictor of Sudden Cardiac Death. IEEE Trans Biomed Eng 2022; 69:3109-3118. [PMID: 35320083 DOI: 10.1109/tbme.2022.3161725] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
OBJECTIVE The clinical significance of QT interval adaptation to heart rate changes has been poorly investigated in atrial fibrillation (AF), since QT delineation in the presence of f-waves is challenging. Therefore, the objective of the present study is to investigate new techniques for QT adaptation estimation in permanent AF. METHODS A multilead strategy based on generalized periodic component analysis is proposed for QT delineation, involving a spatial, linear transformation which emphasizes Twave periodicity and attenuates f-waves. QT adaptation is modeled by a linear, time-invariant filter, whose impulse response describes the dependence between the current QT interval and the preceding RR intervals, followed by a memoryless, possibly nonlinear, function. The QT adaptation time lag is determined from the estimated impulse response. RESULTS Using simulated ECGs in permanent AF, the transformed lead was found to offer more accurate QT delineation and time lag estimation than did the original ECG leads for a wide range of f-wave amplitudes (the time lag estimation error was found to be -0.2+/-0.6 s for SNR = 12 dB). In a population with chronic heart failure and permanent AF, the time lag estimated from the transformed lead was found to have the strongest, statistically significant association with sudden cardiac death (SCD) (hazard ratio = 3.49), whereas none of the original, orthogonal leads had any such association. CONCLUSIONS Periodic component analysis provides more accurate QT delineation and improves time lag estimation in AF. A prolonged adaptation time of the QT interval to heart rate changes is associated with a high risk for SCD. SIGNIFICANCE This study demonstrates that SCD risk markers, originally developed for sinus rhythm, can also be used in AF, provided that Twave periodicity is emphasized. The time lag is a potentially useful marker for identifying patients at high risk for SCD, guiding clinicians in adopting effective therapeutic decisions.
Collapse
|
4
|
Palacios S, Cygankiewicz I, Bayés de Luna A, Pueyo E, Martínez JP. Periodic repolarization dynamics as predictor of risk for sudden cardiac death in chronic heart failure patients. Sci Rep 2021; 11:20546. [PMID: 34654872 PMCID: PMC8519935 DOI: 10.1038/s41598-021-99861-1] [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: 03/22/2021] [Accepted: 09/29/2021] [Indexed: 12/30/2022] Open
Abstract
The two most common modes of death among chronic heart failure (CHF) patients are sudden cardiac death (SCD) and pump failure death (PFD). Periodic repolarization dynamics (PRD) quantifies low-frequency oscillations in the T wave vector of the electrocardiogram (ECG) and has been postulated to reflect sympathetic modulation of ventricular repolarization. This study aims to evaluate the prognostic value of PRD to predict SCD and PFD in a population of CHF patients. 20-min high-resolution (1000 Hz) ECG recordings from 569 CHF patients were analyzed. Patients were divided into two groups, \documentclass[12pt]{minimal}
\usepackage{amsmath}
\usepackage{wasysym}
\usepackage{amsfonts}
\usepackage{amssymb}
\usepackage{amsbsy}
\usepackage{mathrsfs}
\usepackage{upgreek}
\setlength{\oddsidemargin}{-69pt}
\begin{document}$$\hbox {PRD}^+$$\end{document}PRD+ and \documentclass[12pt]{minimal}
\usepackage{amsmath}
\usepackage{wasysym}
\usepackage{amsfonts}
\usepackage{amssymb}
\usepackage{amsbsy}
\usepackage{mathrsfs}
\usepackage{upgreek}
\setlength{\oddsidemargin}{-69pt}
\begin{document}$$\hbox {PRD}^-$$\end{document}PRD-, corresponding to PRD values above and below the optimum cutoff point of PRD in the study population. Univariate Cox regression analysis showed that SCD risk in the \documentclass[12pt]{minimal}
\usepackage{amsmath}
\usepackage{wasysym}
\usepackage{amsfonts}
\usepackage{amssymb}
\usepackage{amsbsy}
\usepackage{mathrsfs}
\usepackage{upgreek}
\setlength{\oddsidemargin}{-69pt}
\begin{document}$$\hbox {PRD}^+$$\end{document}PRD+ group was double the risk in the \documentclass[12pt]{minimal}
\usepackage{amsmath}
\usepackage{wasysym}
\usepackage{amsfonts}
\usepackage{amssymb}
\usepackage{amsbsy}
\usepackage{mathrsfs}
\usepackage{upgreek}
\setlength{\oddsidemargin}{-69pt}
\begin{document}$$\hbox {PRD}^-$$\end{document}PRD- group [hazard ratio (95% CI) 2.001 (1.127–3.554), \documentclass[12pt]{minimal}
\usepackage{amsmath}
\usepackage{wasysym}
\usepackage{amsfonts}
\usepackage{amssymb}
\usepackage{amsbsy}
\usepackage{mathrsfs}
\usepackage{upgreek}
\setlength{\oddsidemargin}{-69pt}
\begin{document}$$\hbox {p}<0.05$$\end{document}p<0.05]. The combination of PRD with other Holter-based ECG indices, such as turbulence slope (TS) and index of average alternans (IAA), improved SCD prediction by identifying groups of patients at high SCD risk. PFD could be predicted by PRD only when combined with TS [hazard ratio 2.758 (1.572–4.838), \documentclass[12pt]{minimal}
\usepackage{amsmath}
\usepackage{wasysym}
\usepackage{amsfonts}
\usepackage{amssymb}
\usepackage{amsbsy}
\usepackage{mathrsfs}
\usepackage{upgreek}
\setlength{\oddsidemargin}{-69pt}
\begin{document}$$\hbox {p}<0.001$$\end{document}p<0.001]. In conclusion, the combination of PRD with IAA and TS can be used to stratify the risk for SCD and PFD, respectively, in CHF patients.
Collapse
Affiliation(s)
- Saúl Palacios
- BSICoS Group, Aragón Institute of Engineering Research, IIS Aragón, Universidad de Zaragoza, Zaragoza, Spain.
| | - Iwona Cygankiewicz
- Department of Electrocardiology, Medical University of Lodz, Lodz, Poland
| | - Antoni Bayés de Luna
- Cardiovascular Research Foundation, Cardiovascular ICCC-Program, Research Institute Hospital de la Santa Creu i Sant Pau, IIB-Sant Pau, Barcelona, Spain
| | - Esther Pueyo
- BSICoS Group, Aragón Institute of Engineering Research, IIS Aragón, Universidad de Zaragoza, Zaragoza, Spain.,CIBER en Bioingeniería, Biomateriales y Nanomedicina (CIBER-BBN), Zaragoza, Spain
| | - Juan Pablo Martínez
- BSICoS Group, Aragón Institute of Engineering Research, IIS Aragón, Universidad de Zaragoza, Zaragoza, Spain.,CIBER en Bioingeniería, Biomateriales y Nanomedicina (CIBER-BBN), Zaragoza, Spain
| |
Collapse
|
5
|
The risk and prevention of sudden death in patients with heart failure with reduced ejection fraction. Curr Opin Cardiol 2020; 35:138-144. [PMID: 31895241 DOI: 10.1097/hco.0000000000000710] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
PURPOSE OF REVIEW Patients with heart failure are at increased risk of sudden cardiac death. The methods to predict patients at high risk of sudden cardiac death in heart failure are neither sensitive nor specific; both overestimating risk in those with ejection fractions less than 35% and not identifying those at risk with ejection fractions greater than 35%. RECENT FINDINGS The absolute risk of sudden cardiac death in patients with heart failure have decreased over the past 20 years. New novel tools are being developed and tested to identify those at higher risk of sudden cardiac death. Reduction in the risk of sudden cardiac death has been achieved with the use of beta-blockers, spironolactone, sacubitril-valsartan, cardiac resynchronization and implantable cardioverter defibrillators. SUMMARY The use of contemporary treatments for patients with heart failure can reduce the risk of sudden cardiac death, but research is required to identify those at highest risk.
Collapse
|
6
|
Martín-Yebra A, Monasterio V, Landreani F, Laguna P, Pablo Martínez J, Caiani EG. Assessment of ventricular repolarization instability in terms of T-wave alternans induced by head-down bed-rest immobilization. Physiol Meas 2019; 40:104001. [DOI: 10.1088/1361-6579/ab4c18] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
|
7
|
Hernando D, Laguna P, Brophy C, Bailon R, Nardelli M, Hocking K, Lazaro J, Alvis B, Gil E, Scilingo EP, Brophy DR, Valenza G. Effect of yoga on pulse rate variability measured from a venous pressure waveform. ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL INTERNATIONAL CONFERENCE 2019; 2019:372-375. [PMID: 31945918 DOI: 10.1109/embc.2019.8856657] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
The benefits of yoga have been studied in different fields, from chronic health conditions to mental disorders, showing that it can help to improve the overall health. In particular, it has been proven that yoga also improves the autonomic function. Heart rate variability (HRV) at rest is commonly used as a non-invasive measure of autonomic regulation of heart rate. Alternatively, pulse rate variability (PRV) has been proposed as a surrogate of HRV. VoluMetrix has developed a novel technology that captures venous waveforms via sensors on the volar aspect of the wrist, called NIVAband. This study aims to assess the effect of yoga in the autonomic nervous system by analyzing the PRV obtained from the NIVA signal. Temporal (statistics of the normal-to-normal intervals), spectral (power in low and high frequency bands) and nonlinear (lagged Poincaré Plot analysis) parameters are analyzed before and after a yoga session in 20 healthy volunteers. The PRV analysis shows an increase in parameters related to parasympathetic activity and overall variability, and a decrease in parameters related to sympathetic activity and mean heart rate. These results support the beneficial effect of yoga in autonomic nervous system, increasing the parasympathetic activity.
Collapse
|
8
|
van Duijvenboden S, Hanson B, Child N, Lambiase PD, Rinaldi CA, Jaswinder G, Taggart P, Orini M. Pulse Arrival Time and Pulse Interval as Accurate Markers to Detect Mechanical Alternans. Ann Biomed Eng 2019; 47:1291-1299. [PMID: 30756263 PMCID: PMC6453876 DOI: 10.1007/s10439-019-02221-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2018] [Accepted: 01/28/2019] [Indexed: 11/10/2022]
Abstract
Mechanical alternans (MA) is a powerful predictor of adverse prognosis in patients with heart failure and cardiomyopathy, but its use remains limited due to the need of invasive continuous arterial pressure recordings. This study aims to assess novel cardiovascular correlates of MA in the intact human heart to facilitate affordable and non-invasive detection of MA and advance our understanding of the underlying pathophysiology. Arterial pressure, respiration, and ECG were recorded in 12 subjects with healthy ventricles during voluntarily controlled breathing at different respiratory rate, before and after administration of beta-blockers. MA was induced by ventricular pacing. A total of 67 recordings lasting approximately 90 s each were analyzed. Mechanical alternans (MA) was measured in the systolic blood pressure. We studied cardiovascular correlates of MA, including maximum pressure rise during systole (dPdtmax), pulse arrival time (PAT), pulse wave interval (PI), RR interval (RRI), ECG QRS complexes and T-waves. MA was detected in 30% of the analyzed recordings. Beta-blockade significantly reduced MA prevalence (from 50 to 11%, p < 0.05). Binary classification showed that MA was detected by alternans in dPdtmax (100% sens, 96% spec), PAT (100% sens, 81% spec) and PI (80% sens, 81% spec). Alternans in PAT and in PI also showed high degree of temporal synchronization with MA (80 ± 33 and 73 ± 40%, respectively). These data suggest that cardiac contractility is a primary factor in the establishment of MA. Our findings show that MA was highly correlated with invasive measurements of PAT and PI. Since PAT and PI can be estimated using non-invasive technologies, these markers could potentially enable affordable MA detection for risk-prediction.
Collapse
Affiliation(s)
- Stefan van Duijvenboden
- Institute of Cardiovascular Science, University College London, London, UK.
- Clinical Pharmacology, William Harvey Research Institute, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, London, UK.
| | - Ben Hanson
- Department of Mechanical Engineering, University College London, London, UK
| | - Nick Child
- Department of Cardiology, Guy's and St. Thomas's Hospital, London, UK
| | - Pier D Lambiase
- Institute of Cardiovascular Science, University College London, London, UK
- Barts Heart Centre, St Bartholomews Hospital, London, UK
| | | | - Gill Jaswinder
- Department of Cardiology, Guy's and St. Thomas's Hospital, London, UK
| | - Peter Taggart
- Institute of Cardiovascular Science, University College London, London, UK
| | - Michele Orini
- Department of Mechanical Engineering, University College London, London, UK
- Barts Heart Centre, St Bartholomews Hospital, London, UK
| |
Collapse
|
9
|
Zormpas C, Mueller-Leisse J, Koenig T, Schmitto JD, Veltmann C, Duncker D. Electrocardiographic changes after implantation of a left ventricular assist device - Potential implications for subcutaneous defibrillator therapy. J Electrocardiol 2018; 52:29-34. [PMID: 30476635 DOI: 10.1016/j.jelectrocard.2018.11.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2018] [Accepted: 11/01/2018] [Indexed: 10/27/2022]
Abstract
BACKGROUND Implantation of a left ventricular assist device (LVAD) leads to a diverse spectrum of changes on the twelve-lead surface electrocardiogram (ECG). We aimed to elucidate the changes of the surface ECG in patients after LVAD implantation potentially impacting ECG based screening tests of subcutaneous implantable cardioverter-defibrillators (S-ICD). METHODS Patients from 2005 until 2017 with a documented twelve-lead ECG before and after LVAD implantation were included. Baseline parameters were obtained through hospital records. The twelve-lead ECGs registered before and after LVAD implantation were analyzed. RESULTS From 415 patients undergoing an LVAD implantation, complete datasets were available for 253 patients. 216 patients (85%) were male. Mean age at time of LVAD implantation was 54.7 ± 12.4 years. The underlying etiology was ischemic cardiomyopathy in 119 (47%), dilated cardiomyopathy in 112 (44%), myocarditis in 8 (3%) and other in 14 (6%). We observed a reduction in the amplitude of the R wave in lead I (p < 0.0001), lead II (p < 0.0001), lead III (p < 0.004), lead aVL (p < 0.001) and lead aVF (p < 0.0001) as well as of the S wave in lead III (p < 0.001) and lead aVR (p < 0.0001) after LVAD implantation. We also noticed a reduction of the R:T ratio in lead I (p < 0.0001) as well as in lead II (p = 0.100) and lead aVF (p = 0.292) although statistically non-significant. CONCLUSION LVAD implantation leads to significant alterations of the surface ECG, especially the R:T ratio in leads I, II and aVF. These leads correlate with the vectors of the ECG based S-ICD screening test. Thus, these ECG changes may impact the continuous eligibility for subcutaneous ICD therapy in patients after LVAD implantation.
Collapse
Affiliation(s)
- Christos Zormpas
- Rhythmology and Electrophysiology, Department of Cardiology and Angiology, Hannover Medical School, Hannover, Germany
| | - Johanna Mueller-Leisse
- Rhythmology and Electrophysiology, Department of Cardiology and Angiology, Hannover Medical School, Hannover, Germany
| | - Thorben Koenig
- Rhythmology and Electrophysiology, Department of Cardiology and Angiology, Hannover Medical School, Hannover, Germany
| | - Jan D Schmitto
- Department of Cardiac, Thoracic, Transplant and Vascular Surgery, Hannover Medical School, Hannover, Germany
| | - Christian Veltmann
- Rhythmology and Electrophysiology, Department of Cardiology and Angiology, Hannover Medical School, Hannover, Germany
| | - David Duncker
- Rhythmology and Electrophysiology, Department of Cardiology and Angiology, Hannover Medical School, Hannover, Germany.
| |
Collapse
|
10
|
Martin-Yebra A, Monasterio V, Cygankiewicz I, Bayes-de-Luna A, Caiani EG, Laguna P, Martinez JP. Post-Ventricular Premature Contraction Phase Correction Improves the Predictive Value of Average T-Wave Alternans in Ambulatory ECG Recordings. IEEE Trans Biomed Eng 2018; 65:635-644. [PMID: 29461965 DOI: 10.1109/tbme.2017.2711645] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
OBJECTIVE We proposed and evaluated a method for correcting possible phase shifts provoked by the presence of ventricular premature contractions (VPCs) for a better assessment of T-wave alternans (TWA). Methods: First, we synthesized ECG signals with artificial TWA in the presence of different noise sources. Then, we assessed the prognostic value for sudden cardiac death (SCD) of the long-term average of TWA amplitude (the index of average alternans, ) in ambulatory ECG signals from congestive heart failure (CHF) and evaluated whether it is sensitive to the presence of VPCs. RESULTS The inclusion of the phase correction after VPC in the processing always improved estimation accuracy of the under different noisy conditions and regardless of the number of the VPCs included in the sequence. It also presented a positive impact on the prognostic value of with increased hazard ratios (from 17% to 29%, depending of the scenario) in comparison to the noninclusion of this step. CONCLUSION The proposed methodology for estimation, which corrects for the possible phase reversal on TWA after the presence of VPCs, represents a robust TWA estimation approach with a significant impact on the prognostic value of for SCD stratification in CHF patients. SIGNIFICANCE An accurate TWA estimation has a potential direct clinical impact on noninvasive SCD stratification, allowing better identification of patients at higher risk and helping clinicians in adopting the most appropriate therapeutic strategy.
Collapse
|
11
|
Ayesta A, Martínez-Sellés H, Bayés de Luna A, Martínez-Sellés M. Prediction of sudden death in elderly patients with heart failure. J Geriatr Cardiol 2018; 15:185-192. [PMID: 29662512 PMCID: PMC5895958 DOI: 10.11909/j.issn.1671-5411.2018.02.008] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2018] [Revised: 02/25/2018] [Accepted: 02/27/2018] [Indexed: 02/06/2023] Open
Abstract
Most heart failure (HF) related mortality is due to sudden cardiac death (SCD) and worsening HF, particularly in the case of reduced ejection fraction. Predicting and preventing SCD is an important goal but most works include no or few patients with advanced age, and the prevention of SCD in elderly patients with HF is still controversial. A recent reduction in the annual rate of SCD has been recently described but it is not clear if this is also true in advanced age patients. Age is associated with SCD, although physicians frequently have the perception that elderly patients with HF die mainly of pump failure, underestimating the importance of SCD. Other clinical variables that have been associated to SCD are symptoms, New York Heart Association functional class, ischemic cause, and comorbidities (chronic obstructive pulmonary disease, renal dysfunction and diabetes). Some test results that should also be considered are left ventricular ejection fraction and diameters, natriuretic peptides, non-sustained ventricular tachycardias and autonomic abnormalities. The combination of all these markers is probably the best option to predict SCD. Different risk scores have been described and, although there are no specific ones for elderly populations, most include age as a risk predictor and some were developed in populations with mean age > 65 years. Finally, it is important to stress that these scores should be able to predict any type of SCD as, although most are due to tachyarrhythmias, bradyarrhythmias also play a role, particularly in the case of the elderly.
Collapse
Affiliation(s)
- Ana Ayesta
- Cardiology Department, Hospital Universitario del Sureste, Arganda del Rey, Madrid, Spain
| | | | | | - Manuel Martínez-Sellés
- Universidad Complutense, Madrid, Spain
- Cardiology Department, Hospital General Universitario Gregorio Marañón, CIVERCV, Universidad Europea, Madrid, Spain
| |
Collapse
|
12
|
Ramírez J, Orini M, Mincholé A, Monasterio V, Cygankiewicz I, Bayés de Luna A, Martínez JP, Laguna P, Pueyo E. Sudden cardiac death and pump failure death prediction in chronic heart failure by combining ECG and clinical markers in an integrated risk model. PLoS One 2017; 12:e0186152. [PMID: 29020031 PMCID: PMC5636125 DOI: 10.1371/journal.pone.0186152] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2017] [Accepted: 09/26/2017] [Indexed: 11/20/2022] Open
Abstract
Background Sudden cardiac death (SCD) and pump failure death (PFD) are common endpoints in chronic heart failure (CHF) patients, but prevention strategies are different. Currently used tools to specifically predict these endpoints are limited. We developed risk models to specifically assess SCD and PFD risk in CHF by combining ECG markers and clinical variables. Methods The relation of clinical and ECG markers with SCD and PFD risk was assessed in 597 patients enrolled in the MUSIC (MUerte Súbita en Insuficiencia Cardiaca) study. ECG indices included: turbulence slope (TS), reflecting autonomic dysfunction; T-wave alternans (TWA), reflecting ventricular repolarization instability; and T-peak-to-end restitution (ΔαTpe) and T-wave morphology restitution (TMR), both reflecting changes in dispersion of repolarization due to heart rate changes. Standard clinical indices were also included. Results The indices with the greatest SCD prognostic impact were gender, New York Heart Association (NYHA) class, left ventricular ejection fraction, TWA, ΔαTpe and TMR. For PFD, the indices were diabetes, NYHA class, ΔαTpe and TS. Using a model with only clinical variables, the hazard ratios (HRs) for SCD and PFD for patients in the high-risk group (fifth quintile of risk score) with respect to patients in the low-risk group (first and second quintiles of risk score) were both greater than 4. HRs for SCD and PFD increased to 9 and 11 when using a model including only ECG markers, and to 14 and 13, when combining clinical and ECG markers. Conclusion The inclusion of ECG markers capturing complementary pro-arrhythmic and pump failure mechanisms into risk models based only on standard clinical variables substantially improves prediction of SCD and PFD in CHF patients.
Collapse
Affiliation(s)
- Julia Ramírez
- Clinical Pharmacology Department, William Harvey Research Institute, John Vane Science Centre, Queen Mary University of London, Charterhouse Square, London, United Kingdom
- * E-mail:
| | - Michele Orini
- Institute of Cardiovascular Science, University College London, London, United Kingdom
- Barts Heart Centre, St Bartholomeus Hospital, London, United Kingdom
| | - Ana Mincholé
- Department of Computer Science, University of Oxford, Oxford, United Kingdom
| | - Violeta Monasterio
- Universidad San Jorge, Campus Universitario, Villanueva de Gállego, Spain
| | - Iwona Cygankiewicz
- Department of Electrocardiology, Medical University of Lodz, Sterling Regional Center for Heart Diseases, Lodz, Poland
| | - Antonio Bayés de Luna
- Catalan Institute of Cardiovascular Sciences, Santa Creu I Sant Pau Hospital, Barcelona, Spain
| | - Juan Pablo Martínez
- Biomedical Signal Interpretation and Computational Simulation (BSICoS) group, Aragón Institute of Engineering Research, IIS Aragón, University of Zaragoza, Zaragoza, Spain
- Biomedical Research Networking Center in Bioengineering, Biomaterials and Nanomedicine (CIBER-BBN), Zaragoza, Spain
| | - Pablo Laguna
- Biomedical Signal Interpretation and Computational Simulation (BSICoS) group, Aragón Institute of Engineering Research, IIS Aragón, University of Zaragoza, Zaragoza, Spain
- Biomedical Research Networking Center in Bioengineering, Biomaterials and Nanomedicine (CIBER-BBN), Zaragoza, Spain
| | - Esther Pueyo
- Biomedical Signal Interpretation and Computational Simulation (BSICoS) group, Aragón Institute of Engineering Research, IIS Aragón, University of Zaragoza, Zaragoza, Spain
- Biomedical Research Networking Center in Bioengineering, Biomaterials and Nanomedicine (CIBER-BBN), Zaragoza, Spain
| |
Collapse
|
13
|
Ramírez J, Orini M, Mincholé A, Monasterio V, Cygankiewicz I, Bayés de Luna A, Martínez JP, Pueyo E, Laguna P. T-Wave Morphology Restitution Predicts Sudden Cardiac Death in Patients With Chronic Heart Failure. J Am Heart Assoc 2017; 6:JAHA.116.005310. [PMID: 28526702 PMCID: PMC5524085 DOI: 10.1161/jaha.116.005310] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
BACKGROUND Patients with chronic heart failure are at high risk of sudden cardiac death (SCD). Increased dispersion of repolarization restitution has been associated with SCD, and we hypothesize that this should be reflected in the morphology of the T-wave and its variations with heart rate. The aim of this study is to propose an electrocardiogram (ECG)-based index characterizing T-wave morphology restitution (TMR), and to assess its association with SCD risk in a population of chronic heart failure patients. METHODS AND RESULTS Holter ECGs from 651 ambulatory patients with chronic heart failure from the MUSIC (MUerte Súbita en Insuficiencia Cardiaca) study were available for the analysis. TMR was quantified by measuring the morphological variation of the T-wave per RR increment using time-warping metrics, and its predictive power was compared to that of clinical variables such as the left ventricular ejection fraction and other ECG-derived indices, such as T-wave alternans and heart rate variability. TMR was significantly higher in SCD victims than in the rest of patients (median 0.046 versus 0.039, P<0.001). When TMR was dichotomized at TMR=0.040, the SCD rate was significantly higher in the TMR≥0.040 group (P<0.001). Cox analysis revealed that TMR≥0.040 was strongly associated with SCD, with a hazard ratio of 3.27 (P<0.001), independently of clinical and ECG-derived variables. No association was found between TMR and pump failure death. CONCLUSIONS This study shows that TMR is specifically associated with SCD in a population of chronic heart failure patients, and it is a better predictor than clinical and ECG-derived variables.
Collapse
Affiliation(s)
- Julia Ramírez
- Biomedical Signal Interpretation and Computational Simulation (BSICoS) Group, Aragón Institute of Engineering Research, IIS Aragón University of Zaragoza, Spain .,Biomedical Research Networking Center in Bioengineering, Biomaterials and Nanomedicine (CIBER-BBN), Madrid, Spain
| | - Michele Orini
- Institute of Cardiovascular Science, University College London, London, United Kingdom.,Barts Heart Centre, London, United Kingdom
| | - Ana Mincholé
- Department of Computer Science, University of Oxford, Oxford, United Kingdom
| | | | - Iwona Cygankiewicz
- Department of Electrocardiology, Medical University of Lodz, Lodz, Poland
| | - Antonio Bayés de Luna
- Catalan Institute of Cardiovascular Sciences, Santa Creu I Sant Pau Hospital, Barcelona, Spain
| | - Juan Pablo Martínez
- Biomedical Signal Interpretation and Computational Simulation (BSICoS) Group, Aragón Institute of Engineering Research, IIS Aragón University of Zaragoza, Spain.,Biomedical Research Networking Center in Bioengineering, Biomaterials and Nanomedicine (CIBER-BBN), Madrid, Spain
| | - Esther Pueyo
- Biomedical Signal Interpretation and Computational Simulation (BSICoS) Group, Aragón Institute of Engineering Research, IIS Aragón University of Zaragoza, Spain.,Biomedical Research Networking Center in Bioengineering, Biomaterials and Nanomedicine (CIBER-BBN), Madrid, Spain
| | - Pablo Laguna
- Biomedical Signal Interpretation and Computational Simulation (BSICoS) Group, Aragón Institute of Engineering Research, IIS Aragón University of Zaragoza, Spain.,Biomedical Research Networking Center in Bioengineering, Biomaterials and Nanomedicine (CIBER-BBN), Madrid, Spain
| |
Collapse
|
14
|
Lewek J, Ptaszynski P, Klingenheben T, Cygankiewicz I. The clinical value of T-wave alternans derived from Holter monitoring. Europace 2016; 19:529-534. [DOI: 10.1093/europace/euw292] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2016] [Accepted: 08/19/2016] [Indexed: 11/12/2022] Open
|
15
|
Disertori M, Gulizia MM, Casolo G, Delise P, Di Lenarda A, Di Tano G, Lunati M, Mestroni L, Salerno-Uriarte J, Tavazzi L. Improving the appropriateness of sudden arrhythmic death primary prevention by implantable cardioverter-defibrillator therapy in patients with low left ventricular ejection fraction. Point of view. J Cardiovasc Med (Hagerstown) 2016; 17:245-55. [PMID: 26895401 PMCID: PMC4768631 DOI: 10.2459/jcm.0000000000000368] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2015] [Revised: 01/10/2016] [Accepted: 01/22/2016] [Indexed: 12/12/2022]
Abstract
It is generally accepted that the current guidelines for the primary prevention of sudden arrhythmic death, which are based on ejection fraction, do not allow the optimal selection of patients with low left ventricular ejection fraction of ischemic and nonischemic etiology for implantation of a cardioverter-defibrillator. Ejection fraction alone is limited in both sensitivity and specificity. An analysis of the risk of sudden arrhythmic death with a combination of multiple tests (ejection fraction associated with one or more arrhythmic risk markers) could partially compensate for these limitations. We propose a polyparametric approach for defining the risk of sudden arrhythmic death using ejection fraction in combination with other clinical and arrhythmic risk markers (i.e. late gadolinium enhancement cardiac magnetic resonance, T-wave alternans, programmed ventricular stimulation, autonomic tone, and genetic testing) that have been validated in nonrandomized trials. In this article, we examine these approaches to identify three subsets of patients who cannot be comprehensively assessed by the current guidelines: patients with ejection fraction of 35% or less and a relatively low risk of sudden arrhythmic death despite the ejection fraction value; patients with ejection fraction of 35% or less and high competitive risk of death due to evolution of heart failure or noncardiac causes; and patients with ejection fraction between 35 and 45% with relatively high risk of sudden arrhythmic death despite the ejection fraction value.
Collapse
MESH Headings
- Arrhythmias, Cardiac/etiology
- Arrhythmias, Cardiac/mortality
- Arrhythmias, Cardiac/physiopathology
- Arrhythmias, Cardiac/prevention & control
- Death, Sudden, Cardiac/etiology
- Death, Sudden, Cardiac/prevention & control
- Defibrillators, Implantable
- Humans
- Primary Prevention/methods
- Stroke Volume/physiology
- Ventricular Dysfunction, Left/complications
- Ventricular Dysfunction, Left/physiopathology
- Ventricular Dysfunction, Left/therapy
Collapse
Affiliation(s)
- Marcello Disertori
- Cardiology Department, S. Chiara Hospital – Healthcare Research and Innovation Program, PAT-FBK, Trento
| | | | | | - Pietro Delise
- Division of Cardiology, Pederzoli Hospital, Peschiera del Garda (VR)
| | - Andrea Di Lenarda
- Cardiovascular Center, Azienda Servizi Sanitari N.1 – University of Trieste, Trieste
| | | | - Maurizio Lunati
- Cardiology Department, Niguarda Ca’ Granda Hospital, Milano, Italy
| | - Luisa Mestroni
- Cardiovascular Institute, University of Colorado Denver AMC, Aurora, Colorado, USA
| | - Jorge Salerno-Uriarte
- Department of Heart Science, Ospedale di Circolo e Fondazione Macchi, University of Insubria, Varese
| | - Luigi Tavazzi
- GVM, Maria Cecilia Hospital, Care and Research – ES Health Science Foundation, Cotignola (RA), Italy
| |
Collapse
|
16
|
Corino VDA, Monacizzo S, Sassi R, Mainardi LT, Martinez JP. Analysis of T-wave Alternans in ambulatory recordings using the ADTWA index. ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL INTERNATIONAL CONFERENCE 2016; 2015:402-5. [PMID: 26736284 DOI: 10.1109/embc.2015.7318384] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Implantable cardioverter defibrillators (ICD) are the most effective way of preventing sudden cardiac death (SCD). However, the implantation of an ICD is an invasive procedure with associated risks and a high cost. Therefore, it is necessary to determine non-invasive risk markers that identify patients at a higher risk of suffering malignant arrhytmias. One of the most promising non-invasive indices is T-wave alternans (TWA). This work assesses T-wave alternans using the Amplitude of Dominant T-Wave Alternans (ADTWA), that is derived from the dominant T wave associated to a number of consecutive beats. Data from 650 patients with heart failure enrolled in the MUSIC study were analyzed. ADTWA have higher values increasing heart rate. ADTWA was also significantly higher in SCD patients than in survivors (survivors vs. SCD: 6.60±1.98 vs. 7.55±2.53, p=0.01). ADTWA seems a promising index to identify patients with heart failure at higher risk of SCD.
Collapse
|
17
|
Martín-Yebra A, Caiani EG, Monasterio V, Pellegrini A, Laguna P, Martínez JP. Evaluation of T-wave alternans activity under stress conditions after 5 d and 21 d of sedentary head-down bed rest. Physiol Meas 2015; 36:2041-55. [DOI: 10.1088/0967-3334/36/10/2041] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
|
18
|
Automatic SVM classification of sudden cardiac death and pump failure death from autonomic and repolarization ECG markers. J Electrocardiol 2015; 48:551-7. [PMID: 25912974 DOI: 10.1016/j.jelectrocard.2015.04.002] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2014] [Indexed: 11/24/2022]
Abstract
BACKGROUND Considering the rates of sudden cardiac death (SCD) and pump failure death (PFD) in chronic heart failure (CHF) patients and the cost-effectiveness of their preventing treatments, identification of CHF patients at risk is an important challenge. In this work, we studied the prognostic performance of the combination of an index potentially related to dispersion of repolarization restitution (Δα), an index quantifying T-wave alternans (IAA) and the slope of heart rate turbulence (TS) for classification of SCD and PFD. METHODS Holter ECG recordings of 597 CHF patients with sinus rhythm enrolled in the MUSIC study were analyzed and Δα, IAA and TS were obtained. A strategy was implemented using support vector machines (SVM) to classify patients in three groups: SCD victims, PFD victims and other patients (the latter including survivors and victims of non-cardiac causes). Cross-validation was used to evaluate the performance of the implemented classifier. RESULTS Δα and IAA, dichotomized at 0.035 (dimensionless) and 3.73 μV, respectively, were the ECG markers most strongly associated with SCD, while TS, dichotomized at 2.5 ms/RR, was the index most strongly related to PFD. When separating SCD victims from the rest of patients, the individual marker with best performance was Δα≥0.035, which, for a fixed specificity (Sp) of 90%, showed a sensitivity (Se) value of 10%, while the combination of Δα and IAA increased Se to 18%. For separation of PFD victims from the rest of patients, the best individual marker was TS ≤ 2.5 ms/RR, which, for Sp=90%, showed a Se of 26%, this value being lower than Se=34%, produced by the combination of Δα and TS. Furthermore, when performing SVM classification into the three reported groups, the optimal combination of risk markers led to a maximum Sp of 79% (Se=18%) for SCD and Sp of 81% (Se=14%) for PFD. CONCLUSIONS The results shown in this work suggest that it is possible to efficiently discriminate SCD and PFD in a population of CHF patients using ECG-derived risk markers like Δα, TS and IAA.
Collapse
|
19
|
Quan XQ, Zhou HL, Ruan L, Lv JG, Yao JH, Yao F, Huang K, Zhang CT. Ability of ambulatory ECG-based T-wave alternans to modify risk assessment of cardiac events: a systematic review. BMC Cardiovasc Disord 2014; 14:198. [PMID: 25528490 PMCID: PMC4289555 DOI: 10.1186/1471-2261-14-198] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2014] [Accepted: 12/09/2014] [Indexed: 11/16/2022] Open
Abstract
Background Exercise-based spectral T-wave alternans (TWA) has been proposed as a noninvasive tool-identifying patients at risk of sudden cardiac death (SCD) and cardiac mortality. Prior studies have indicated that ambulatory electrocardiogram (AECG)-based TWA is an important alternative platform to exercise for risk stratification of cardiac events. This study sought to review data regarding 24-hour AECG-based TWA and to discuss its potential role in risk stratification of fatal cardiac events across a series of patient risk profiles. Methods Prospective clinical studies of the predictive value of AECG-based TWA obtained with daily activity published between January 1990 and November 2014 were retrieved. Major endpoints included composite endpoint of SCD, cardiac mortality, and severe arrhythmic events. Results Data were accumulated from 5 studies involving a total of 1,588 patients, including 317 positive and 1,271 negative TWA results. Compared with the negative group, positive group showed increased rates of SCD (hazard ratio [HR]: 7.49, 95% confidence interval [CI]: 2.65 to 21.15), cardiac mortality (HR: 4.75, 95% CI: 0.42 to 53.55), and composite endpoint (SCD, cardiac mortality, and severe arrhythmic events, HR: 5.94, 95% CI: 1.80 to 19.63). For the 4 studies evaluating TWA measured using the modified moving average method, the HR associated with a positive versus negative TWA result was 9.51 (95% CI: 4.99 to 18.11) for the composite endpoint. Conclusions The positive group of AECG-based TWA has a nearly six-fold risk of severe outcomes compared with the negative group. Therefore, AECG-based TWA provides an accurate means of predicting fatal cardiac events. Electronic supplementary material The online version of this article (doi:10.1186/1471-2261-14-198) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
| | | | | | | | | | | | | | - Cun-Tai Zhang
- Department of Geriatrics, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China.
| |
Collapse
|
20
|
Orini M, Hanson B, Monasterio V, Martínez JP, Hayward M, Taggart P, Lambiase P. Comparative evaluation of methodologies for T-wave alternans mapping in electrograms. IEEE Trans Biomed Eng 2014; 61:308-16. [PMID: 24235296 DOI: 10.1109/tbme.2013.2289304] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Electrograms (EGM) recorded from the surface of the myocardium are becoming more and more accessible. T-wave alternans (TWA) is associated with increased vulnerability to ventricular tachycardia/fibrillation and it occurs before the onset of ventricular arrhythmias. Thus, accurate methodologies for time-varying alternans estimation/detection in EGM are needed. In this paper, we perform a simulation study based on epicardial EGM recorded in vivo in humans to compare the accuracy of four methodologies: the spectral method (SM), modified moving average method, laplacian likelihood ratio method (LLR), and a novel method based on time-frequency distributions. A variety of effects are considered, which include the presence of wide band noise, respiration, and impulse artifacts. We found that 1) EGM-TWA can be detected accurately when the standard deviation of wide-band noise is equal or smaller than ten times the magnitude of EGM-TWA. 2) Respiration can be critical for EGM-TWA analysis, even at typical respiratory rates. 3) Impulse noise strongly reduces the accuracy of all methods, except LLR. 4) If depolarization time is used as a fiducial point, the localization of the T-wave is not critical for the accuracy of EGM-TWA detection. 5) According to this study, all methodologies provided accurate EGM-TWA detection/quantification in ideal conditions, while LLR was the most robust, providing better detection-rates in noisy conditions. Application on epicardial mapping of the in vivo human heart shows that EGM-TWA has heterogeneous spatio-temporal distribution.
Collapse
|
21
|
Ramírez J, Laguna P, Bayés de Luna A, Malik M, Pueyo E. QT/RR and T-peak-to-end/RR curvatures and slopes in chronic heart failure: relation to sudden cardiac death. J Electrocardiol 2014; 47:842-8. [PMID: 25200899 DOI: 10.1016/j.jelectrocard.2014.08.013] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2014] [Indexed: 11/26/2022]
Abstract
BACKGROUND Previous studies investigated the QT/RR relationship by linear regressions of QT and RR intervals. However, the pattern of the QT/RR relationship is not necessarily linear. This study investigated the QT/RR and T-peak-to-end (Tpe)/RR curvatures and corresponding slopes in chronic heart failure (CHF) patients, and studied their differences between sudden cardiac death (SCD) victims and others. METHODS Holter ECG recordings of 650 CHF patients were analyzed. RR, QT and Tpe series were obtained and for each patient, the data of each subject were fitted with a non-linear regression function of the form: QT=χ+ϕ(1-RR(γ)), where γ is the QT/RR curvature. The same regression formula was applied to the Tpe interval series. The slopes (dimensionless units) were calculated at the averaged RR intervals and at RR of 1 second. RESULTS The median (difference between 75th and 25th percentile) of the curvature parameter was 0.226 (2.39) for QT/RR and -0.002 (3.64) for Tpe/RR in the overall sample. For the QT/RR slope, these values were 0.170 (0.12) and 0.190 (0.10) when evaluated at RR=1 and at the averaged RR, respectively, while for the Tpe/RR slope the values were 0.016 (0.04) and 0.020 (0.04), respectively. The Tpe/RR slope showed high statistical significance for separation of SCD victims and others, particularly when evaluated at the averaged RR (median values of 0.040 vs 0.020, p=0.002), but also when evaluated at RR=1 second (0.026 vs 0.015, p=0.023). Patients with values of Tpe/RR slope above 0.042 had double incidence of SCD, for the case of the slope being evaluated at RR=1 second, and triple incidence for the case of the slope being evaluated at the averaged RR. The QT/RR slope and curvature, as well as the Tpe/RR curvature, were not different in SCD victims and in others. CONCLUSIONS Non-linear regression models based on curvature and slope characteristics, individually obtained for each patient, were used to characterize the QT/RR and Tpe/RR relationships. Steeper Tpe/RR slopes, obtained after adjusting for the curvature parameter, were associated with higher incidence of SCD. The curvature parameter itself did not show SCD predictive value.
Collapse
Affiliation(s)
- Julia Ramírez
- Centro de Investigación Biomédica en Red (CIBER), Spain; Aragón Institute of Engineering Research, IIS Aragón, Universidad de Zaragoza, Zaragoza, Spain.
| | - Pablo Laguna
- Centro de Investigación Biomédica en Red (CIBER), Spain; Aragón Institute of Engineering Research, IIS Aragón, Universidad de Zaragoza, Zaragoza, Spain
| | - Antonio Bayés de Luna
- Institut Catalad'Ciencies Cardiovasculars, Hospital Santa Creu I Sant Pau, Barcelona, Spain
| | - Marek Malik
- St. Paul's Cardiac Electrophysiology, University of London, and Imperial College, London, UK
| | - Esther Pueyo
- Centro de Investigación Biomédica en Red (CIBER), Spain; Aragón Institute of Engineering Research, IIS Aragón, Universidad de Zaragoza, Zaragoza, Spain
| |
Collapse
|
22
|
Song T, Qu XF, Zhang YT, Cao W, Han BH, Li Y, Piao JY, Yin LL, Da Cheng H. Usefulness of the heart-rate variability complex for predicting cardiac mortality after acute myocardial infarction. BMC Cardiovasc Disord 2014; 14:59. [PMID: 24886422 PMCID: PMC4023175 DOI: 10.1186/1471-2261-14-59] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2014] [Accepted: 04/28/2014] [Indexed: 11/10/2022] Open
Abstract
Background Previous studies indicate that decreased heart-rate variability (HRV) is related to the risk of death in patients after acute myocardial infarction (AMI). However, the conventional indices of HRV have poor predictive value for mortality. Our aim was to develop novel predictive models based on support vector machine (SVM) to study the integrated features of HRV for improving risk stratification after AMI. Methods A series of heart-rate dynamic parameters from 208 patients were analyzed after a mean follow-up time of 28 months. Patient electrocardiographic data were classified as either survivals or cardiac deaths. SVM models were established based on different combinations of heart-rate dynamic variables and compared to left ventricular ejection fraction (LVEF), standard deviation of normal-to-normal intervals (SDNN) and deceleration capacity (DC) of heart rate. We tested the accuracy of predictors by assessing the area under the receiver-operator characteristics curve (AUC). Results We evaluated a SVM algorithm that integrated various electrocardiographic features based on three models: (A) HRV complex; (B) 6 dimension vector; and (C) 8 dimension vector. Mean AUC of HRV complex was 0.8902, 0.8880 for 6 dimension vector and 0.8579 for 8 dimension vector, compared with 0.7424 for LVEF, 0.7932 for SDNN and 0.7399 for DC. Conclusions HRV complex yielded the largest AUC and is the best classifier for predicting cardiac death after AMI.
Collapse
Affiliation(s)
| | - Xiu Fen Qu
- Department of Cardiology, the First Affiliated Hospital of Harbin Medical University, No,23 Youzheng Street, Nangang District, Harbin City 150001, Heilongjiang Province, China.
| | | | | | | | | | | | | | | |
Collapse
|
23
|
Ragupathi L, Pavri BB. Tools for risk stratification of sudden cardiac death: a review of the literature in different patient populations. Indian Heart J 2014; 66 Suppl 1:S71-81. [PMID: 24568833 DOI: 10.1016/j.ihj.2013.12.035] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2013] [Revised: 12/09/2013] [Accepted: 12/10/2013] [Indexed: 12/14/2022] Open
Abstract
While various modalities to determine risk of sudden cardiac death (SCD) have been reported in clinical studies, currently reduced left ventricular ejection fraction remains the cornerstone of SCD risk stratification. However, the absolute burden of SCD is greatest amongst populations without known cardiac disease. In this review, we summarize the evidence behind current guidelines for implantable cardioverter defibrillator (ICD) use for the prevention of SCD in patients with ischemic heart disease (IHD). We also evaluate the evidence for risk stratification tools beyond clinical guidelines in the general population, patients with IHD, and patients with other known or suspected medical conditions.
Collapse
Affiliation(s)
| | - Behzad B Pavri
- Thomas Jefferson University Hospital, Philadelphia, PA, USA.
| |
Collapse
|
24
|
Prognostic value of average T-wave alternans and QT variability for cardiac events in MADIT-II patients. J Electrocardiol 2013; 46:480-6. [DOI: 10.1016/j.jelectrocard.2013.08.004] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2013] [Indexed: 11/19/2022]
|
25
|
Affiliation(s)
- Shlomo Stern
- Hebrew University of Jerusalem, Emeritus Professor of Medicine, Jerusalem 94631, Israel.
| |
Collapse
|
26
|
Current World Literature. Curr Opin Cardiol 2013; 28:369-79. [DOI: 10.1097/hco.0b013e328360f5be] [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: 11/26/2022]
|
27
|
Current world literature. Curr Opin Cardiol 2013; 28:259-68. [PMID: 23381096 DOI: 10.1097/hco.0b013e32835ec472] [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: 11/25/2022]
|
28
|
Tereshchenko LG, Cygankiewicz I, McNitt S, Vazquez R, Bayes-Genis A, Han L, Sur S, Couderc JP, Berger RD, de Luna AB, Zareba W. Predictive value of beat-to-beat QT variability index across the continuum of left ventricular dysfunction: competing risks of noncardiac or cardiovascular death and sudden or nonsudden cardiac death. Circ Arrhythm Electrophysiol 2012; 5:719-27. [PMID: 22730411 DOI: 10.1161/circep.112.970541] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
BACKGROUND The goal of the present study was to determine the predictive value of beat-to-beat QT variability in heart failure patients across the continuum of left ventricular dysfunction. METHODS AND RESULTS Beat-to-beat QT variability index (QTVI), log-transformed heart rate variance, normalized QT variance, and coherence between heart rate variability and QT variability have been measured at rest during sinus rhythm in 533 participants of the Muerte Subita en Insuficiencia Cardiaca heart failure study (mean age, 63.1±11.7; men, 70.6%; left ventricular ejection fraction >35% in 254 [48%]) and in 181 healthy participants from the Intercity Digital Electrocardiogram Alliance database. During a median of 3.7 years of follow-up, 116 patients died, 52 from sudden cardiac death (SCD). In multivariate competing risk analyses, the highest QTVI quartile was associated with cardiovascular death (subhazard ratio, 1.67 [95% CI, 1.14-2.47]; P=0.009) and, in particular, with non-SCD (subhazard ratio, 2.91 [1.69-5.01]; P<0.001). Elevated QTVI separated 97.5% of healthy individuals from subjects at risk for cardiovascular (subhazard ratio, 1.57 [1.04-2.35]; P=0.031) and non-SCD in multivariate competing risk model (subhazard ratio, 2.58 [1.13-3.78]; P=0.001). No interaction between QTVI and left ventricular ejection fraction was found. QTVI predicted neither noncardiac death (P=0.546) nor SCD (P=0.945). Decreased heart rate variability rather than increased QT variability was the reason for increased QTVI in the present study. CONCLUSIONS Increased QTVI because of depressed heart rate variability predicts cardiovascular mortality and non-SCD but neither SCD nor extracardiac mortality in heart failure across the continuum of left ventricular dysfunction. Abnormally augmented QTVI separates 97.5% of healthy individuals from heart failure patients at risk.
Collapse
Affiliation(s)
- Larisa G Tereshchenko
- Division of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA.
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|