Predictors of sustained ventricular arrhythmias in cardiac resynchronization therapy (original) (raw)
JACC: Clinical Electrophysiology, 2019
OBJECTIVES This study assessed the arrhythmic risk of cardiac resynchronization therapy (CRT) patients who improved beyond Heart Rhythm Society/European Society of Cardiology guidelines for an implantable cardioverter-defibrillator (ICD) (ischemic cardiomyopathy: left ventricular ejection fraction [LVEF] >35% or New York Heart Association [NYHA] functional class I and if LVEF was 31% to 35%; nonischemic cardiomyopathy: LVEF >35% or NYHA functional class I and if LVEF was #35%). BACKGROUND It is currently unknown whether protection with a defibrillator is still warranted in patients who respond to CRT. METHODS This study compared the risk of ICD therapy for any ventricular tachyarrhythmia (VTA) and for fast VTA ($ 200 beats/min) among patients implanted with a CRT with a defibrillator (CRT-D) in the MADIT-CRT (Multicenter Automatic Defibrillator Implantation Trial with Cardiac Resynchronization Therapy) study (N ¼ 734) who improved at 1 year beyond guideline recommendations for primary ICD therapy (group A) with those who remained within guideline recommendations for an ICD at 1 year (group B). RESULTS Most patients implanted with a CRT-D device improved at 1 year beyond guideline indications for an ICD (90%). Multivariate analysis showed lower risks for any VTA and fast VTA among group A patients versus group B patients (57% risk reduction; p ¼ 0.0006 and 46% risk reduction; p ¼ 0.068, respectively). However, the 2-year rates of any VTA and fast VTA among CRT patients who improved beyond guidelines indications for an ICD was still substantial (VTA: 13% and 29%, and fast VTA: 7% and 16%, respectively). CONCLUSIONS Most patients with mild heart failure implanted with a CRT device experience an improvement in left ventricular function and/or NYHA functional class beyond guideline recommendations for primary ICD therapy. However, despite this pronounced CRT response, there remains a substantial VTA risk, and protection with a defibrillator may still be warranted in this population.
Europace, 2008
In patients with advanced heart failure (HF) and prolonged QRS interval, cardiac resynchronization therapy (CRT) reduces symptoms and risk of death. The added benefit of an implantable cardioverter defibrillator (ICD) remains questionable in some patients. Methods and results In 332 HF patients treated with CRT-D (CRT with ICD) [65 + 10 years, 86% men, 23% New York Heart Association (NYHA) class II, 65% class III, and 11% class IV, 70% primary prevention, 55% ischaemic cardiomyopathy, left ventricular ejection fraction 25 + 7.5%, and QRS width 167 + 32 ms], we evaluated the relationship between functional status change, death at 6-month follow-up (FU), and the occurrence of ventricular tachyarrhythmia/ventricular fibrillation (VT/VF). A total of 68 patients (20.5%) experienced 1266 spontaneous episodes of VT/VF during FU. There was no difference in baseline characteristics between patients with or without VT/VF, except for ICD indication (primary or secondary prevention). Improvement in NYHA class was significantly associated with a decreased occurrence of VT/VF (P ¼ 0.004). Sixteen patients who died had significantly more often VT/VF than the survivors (50 vs. 19%, P ¼ 0.007). Conclusion Within the initial 6-month post-CRT therapy, 20% of patients received an appropriate ICD therapy. Patients improving on NYHA class (responders to CRT) have less VT/VF episodes than non-responders. Discriminant criteria for CRT response are awaited to optimize the choice of the device (CRT alone, defibrillator alone, or CRT-D).
Circulation: Arrhythmia and Electrophysiology, 2013
Background— Although cardiac resynchronization therapy (CRT) can improve left ventricular ejection fraction (LVEF), it is not known whether a specific level of improvement will predict future implantable cardioverter defibrillator (ICD) therapy. Methods and Results— CRT-defibrillator (CRT-D) was implanted in 423 patients at 1 institution between October 2, 2001 and January 19, 2007. A retrospective analysis was performed to evaluate the relationship between post–CRT-D LVEF and ICD therapy for ventricular tachyarrhythmias. A landmark population of 270 patients, with post–CRT-D LVEF measured and no ICD therapy within 1 year of device implantation, was followed for subsequent outcomes. Of these, 22 patients (8.2%) had subsequent appropriate ICD therapy over a median follow-up of 1.5 years. The estimated 2-year risk of appropriate ICD therapy is 3.0% (95% confidence interval [95% CI], 0%–6.3%), 2.1% (95% CI, 0%–5.0%), and 1.5% (95% CI, 0%–3.9%) for post–CRT-D LVEF of 45%, 50%, and 55%, ...
Frontiers in physiology, 2014
Aim and Hypothesis: Despite the proven symptomatic and mortality benefit of cardiac resynchronization therapy (CRT), there is anecdotal evidence it may be pro-arrhythmic in some patients. We aimed to identify if there were significant differences in the incidence of ventricular arrhythmias (VAs) in patients undergoing CRT-D and implantable cardioverter-defibrillators (ICD) implantation for primary prevention indication. We hypothesized that CRT is unlikely to be pro-arrhythmic based on the positive mortality and morbidity data from large randomized trials. A retrospective analysis of device therapies for VA in a primary prevention device cohort was performed. Patients with ischemic (IHD) and non-ischemic (DCM) cardiomyopathy and ICD or CRT+ICD devices (CRT-D) implanted between 2005 and 2007 without prior history of sustained VA were included for analysis. VA episodes were identified from stored electrograms and defined as sustained (VT/VF) if therapy [anti-tachycardia pacing (ATP) o...
Journal of Cardiovascular Electrophysiology, 2018
Introduction: Adverse electrical remodeling (AER), represented here as the sum absolute QRST integral (SAI QRST), has previously been shown to be directly associated with the risk for ventricular arrhythmia (VA). Cardiac resynchronization therapy (CRT) is known to reduce the risk for VA through various mechanisms, including reverse remodeling, and we aimed to evaluate the association between baseline AER and the risk for VA in CRT recipients. Methods and results: The study population comprised 961 CRT-D implanted patients from the MADIT CRT study. The relationship between SAI QRST, VA risk, and VA risk/death was evaluated as a continuous and as a categorical variable-tertiles (T1 ≤ 0.527, T2 0.528-0.766, T3 > 0.766). In a multivariable model, AER was inversely associated with the risk of VA. Each unit increase in SAI QRST was associated with 64% (P = 0.007) and 54% (P = 0.003) decrease in the risk of VA and VA/death, respectively. Patients with high SAI QRST (T3) and medium SAI QRST (T2) had 52% (P < 0.001) and 32% (P = 0.027) reduced risk for VA and 44% (P = 0.002) and 26% (P = 0.055) reduced risk for VA/death as compared with patients with low SAI QRST (T1), respectively. Conclusion: In CRT implanted patients with mild heart failure, baseline AER was inversely associated with the risk for VA and VA/death; this is a finding that contradicts the relationship previously reported in non-CRT implanted patients. We theorize that CRT may abate the process of AER; however, characterization of this mechanism requires further study.
Pacing and Clinical Electrophysiology, 2020
Background: Permanent right ventricular pacing (RVP) results in cardiac dyssynchrony that may lead to heart failure and may be an indication for the use of cardiac resynchronization therapy (CRT). The study aimed to evaluate predictors of outcomes in patients with pacinginduced cardiomyopathy (PICM) if upgraded to CRT. Methods: 115 patients, 75.0 years old (IQR 67.0-80.0), were upgraded to CRT due to the decline in left ventricle ejection fraction (LVEF) caused by the long-term RVP. A retrospective analysis was performed using data from hospital and outpatient clinic records and survival data from the national health system. Results: The prior percentage of RVP was 100.0% (IQR 97.0-100.0), with a QRS duration of 180.0ms (IQR 160.0-200.0). LVEF at the time of the upgrade procedure was 27.0% (IQR 21.0-32.75). The mean follow-up was 980±522 days. The primary endpoint, death from any cause, was met by 26 (22%) patients. Age >82 years (HR 5.96; 95%CI 2.24-15.89; p=0.0004) and pre-CRT implantation LVEF <20% (HR 5.63; 95%CI 2.19-14.47; p=0.0003), but neither the cardioverter-defibrillator (ICD) implantation (HR 1.00; 95%CI 0.45-2.22; p=1.00), nor the presence of atrial fibrillation (HR 1.22; 95%CI 0.56-2.64; p=0.62), were independently associated with all-cause mortality.
Revista Portuguesa de Cardiologia (English Edition), 2019
The aim of this study was to document clinical practice in Portugal regarding the use of electronic cardiac devices in patients with heart failure (HF) and reduced left ventricular ejection fraction (LVEF). Methods: The Síncrone study was an observational prospective multicenter registry conducted in 16 centers in Portugal between 2006 and 2014. It included adult patients with a diagnosis of HF, LVEF <35% and indication for implantable cardioverter-defibrillator (ICD) and/or cardiac resynchronization therapy (CRT) devices, according to the recommendations of the European Society of Cardiology at the beginning of the study. Patients were followed for one year according to the practice of each center. Results: A total of 486 patients were included in the registry, half of whom received an ICD and the other half a CRT pacemaker (CRT-P) or CRT defibrillator (CRT-D). Mean age was 65±12 years and the most frequent causes of HF were ischemic (47%) and idiopathic dilated cardiomyopathy (28%). Overall mortality at one year was 3.6% and the hospitalization rate was 11%, significantly higher in patients with CRT-P/CRT-D than with ICD (17% vs. 5.6%, p<0.001). Patients who received CRT-P/CRT-D experienced significant reductions in QRS duration (160±21 vs. 141±24 ms, p<0.001) as well as improvement in New York Heart Association functional class.