Prognostic Significance of Nonsustained Ventricular Tachycardia Episodes Occurring Early After Implantable Cardioverter-Defibrillator Implantation Among Patients With Left Ventricular Dysfunction

Long-term prognosis and prognostic factors after primary prophylactic implantable cardioverter-defibrillator therapy

BACKGROUND

Little is known regarding which patients with ischemic cardiomyopathy (ICM) should be considered for prophylactic therapies, such as an implantable cardioverter-defibrillator (ICD), in the primary percutaneous intervention era. The aim of this study was to investigate the influence of non-sustained ventricular tachycardia (NSVT) on major adverse cardiac events (MACE) in heart failure with reduced ejection fraction (HFrEF) patients.

METHODS

We retrospectively analyzed patients of ICM and non-ICM who underwent ICD implantation at our institute from October 2006 to August 2020. MACE were defined as composite outcome of cardiovascular death, heart failure hospitalization, and appropriate ICD therapies.

RESULTS

A total of 167 patients were enrolled [male, 138 (83 %); age, 62.1 ± 11.7 years; left ventricular ejection fraction, 23.5 ± 6.1 %; left ventricular diastolic diameter, 67.4 ± 9.0 mm; atrial fibrillation, 47 (28 %); NSVT, 124 (74 %); use of class III antiarrhythmic drugs, 55 (33 %); ischemic cardiomyopathy, 56 (34 %); cardiac resynchronization therapy, 73 (44 %)]. The median follow-up duration was 61 months. MACE occurred with 71 patients (43 %). When comparing baseline characteristics of the patients, left ventricular ejection fraction (p = 0.02) and atrial fibrillation (p = 0.04) were significantly associated with MACE. The multivariable Cox analysis for the target variable MACE identified atrial fibrillation (hazard ratio 2.00; 95 % confidence index 1.18-3.37; p = 0.01) as an independent predictor for MACE.

CONCLUSIONS

Prior NSVT before ICD implantation was not an independent predictor of future MACE in patients with HFrEF with primary prophylactic ICD. In contrast, atrial fibrillation was associated with worse prognosis. To predict the prognosis of patients with primary prophylactic ICD, these factors should be assessed as comprehensive risk stratification factors for MACE.

Ventricular tachycardia risk prediction with an abbreviated duration mobile cardiac telemetry

Background

Ventricular tachycardia (VT) occurs intermittently, unpredictably, and has potentially lethal consequences.

Objective

Our aim was to derive a risk prediction model for VT episodes ≥10 beats detected on 30-day mobile cardiac telemetry based on the first 24 hours of the recording.

Methods

We included patients who were monitored for 2 to 30 days in the United States using full-disclosure mobile cardiac telemetry, without any VT episode ≥10 beats on the first full recording day. An elastic net prediction model was derived for the outcome of VT ≥10 beats on monitoring days 2 to 30. Potential predictors included age, sex, and electrocardiographic data from the first 24 hours: heart rate; premature atrial and ventricular complexes occurring as singlets, couplets, triplets, and runs; and the fastest rate for each event. The population was randomly split into training (70%) and testing (30%) samples.

Results

In a population of 19,781 patients (mean age 65.3 ± 17.1 years, 43.5% men), with a median recording time of 18.6 ± 9.6 days, 1510 patients had at least 1 VT ≥10 beats. The prediction model had good discrimination in the testing sample (area under the receiver-operating characteristic curve 0.7584, 95% confidence interval 0.7340-0.7829). A model excluding age and sex had an equally good discrimination (area under the receiver-operating characteristic curve 0.7579, 95% confidence interval 0.7332-0.7825). In the top quintile of the score, more than 1 in 5 patients had a VT ≥10 beats, while the bottom quintile had a 98.2% negative predictive value.

Conclusion

Our model can predict risk of VT ≥10 beats in the near term using variables derived from 24-hour electrocardiography, and could be used to triage patients to extended monitoring.

Device-detected non-sustained ventricular tachycardia in adult congenital heart disease without tetralogy of fallot

OBJECTIVES

To evaluate any association between non-sustained ventricular tachycardia (NSVT) detected by intra-cardiac device and clinical outcomes in repaired adult congenital heart disease (ACHD) without tetralogy of Fallot (TOF).

BACKGROUND

NSVT portends a higher risk of serious ventricular tachyarrhythmia in TOF. However its clinical significance when incidentally detected by implantable cardiac device is not well elucidated in non-TOF ACHD cohort.

METHODS

We performed a single center, retrospective, longitudinal follow-up study in repaired ACHD (≥ 18 years) patients without TOF who hosted a pacemaker or automatic implantable cardiac defibrillator (AICD). The cohort was divided based on presence/absence of device detected NSVT. The primary end-point was a composite of sustained ventricular tachycardia (VT), ventricular fibrillation (VF), or sudden cardiac death (SCD).

RESULTS

158 patients [male 56.3%, median (IQR) age of 35 (28-43) years at last follow-up] with longitudinal post-implant follow-up duration of 8 (5-12) years were included. NSVT was detected in 52 (33%) patients. The primary composite end-point was more frequent in NSVT group [11.5% vs. 2.8%; p = 0.04]. Patients with NSVT were i) older at the time of initial implant (age 25 vs. 18 years, p = 0.011) and more frequently demonstrated ii) systemic ventricular dysfunction (44% vs. 26%; p = 0.015), as well as iii) history of ventriculotomy (38% vs. 21%;p = 0.017).

CONCLUSIONS

In our repaired ACHD cohort, we noted a significant association between device-detected-NSVT and the primary composite end-point of sustained VT/VF or SCD. Systemic ventricular dysfunction and history of ventriculotomy were more frequent in the NSVT group and likely constituted the clinical milieu. This article is protected by copyright. All rights reserved.

Prevalence and prognostic association of ventricular arrhythmia in non-ischaemic heart failure patients: results from the DANISH trial

AIMS

Improved risk stratification to identify non-ischaemic heart failure patients who will benefit from primary prophylactic implantable cardioverter-defibrillator (ICD) is needed. We examined the potential of ventricular arrhythmia to identify patients who could benefit from an ICD.

METHODS AND RESULTS

A total of 850 non-ischaemic systolic heart failure patients with left ventricle ≤35% and elevated N-terminal pro-brain natriuretic peptides had a 24-h Holter monitor recording performed. We examined present non-sustained ventricular tachycardia (NSVT), defined as ≥3 consecutive premature ventricular contractions (PVCs) with a rate of ≥100/min, and number of PVCs per hour stratified into low (<30) and high burden (≥30) groups. Outcome measures were overall mortality, sudden cardiac death (SCD), and cardiovascular death (CVD). In total, 193 patients died, 49 from SCD and 125 from CVD. Non-sustained ventricular tachycardia (365 patients) was significantly associated with increased all-cause mortality [hazard ratio (HR) 1.47; 95% confidence interval (CI) 1.07-2.03; P = 0.02] and to CVD (HR 1.89; CI 1.25-2.87; P = 0.003). High burden PVC (352 patients) was associated with increased all-cause mortality (HR1.38; CI 1.00-1.90; P = 0.046) and with CVD (HR 1.78; CI 1.19-2.66; P = 0.005). There was no statistically significant association with SCD for neither NSVT nor PVC. In interaction analyses, neither NSVT (P = 0.56) nor high burden of PVC (P = 0.97) was associated with survival benefit from ICD implantation.

CONCLUSION

Ventricular arrhythmia in non-ischaemic heart failure patients was associated with a worse prognosis but could not be used to stratify patients to ICD implantation.

Prognosis After Finding Incidental Ventricular Tachycardia on Ambulatory Electrocardiogram-recording

The prognostic significance of incidental non-sustained ventricular tachycardia (NSVT) in subjects without apparent heart disease is unknown. We aimed to evaluate short- and long-term prognosis of NSVT in the Copenhagen Holter Study cohort. From the study, 678 middle-aged and elderly subjects had minimum 48 hours of Holter-recording, laboratory testing and physician-based examination and questionnaire performed. Median follow-up time was 14.7 years. NSVT was defined as runs of minimum three premature ventricular complexes. The primary end-point was a combination of cardiovascular mortality, acute myocardial infarction, coronary revascularization or stroke. Secondary endpoints were all-cause mortality and components of the primary end-point. We found that 72 (10.6%) had minimum one NSVT event on 48-hour Holter-recording. The primary end-point occurred more frequently in patients with NSVT than those without: 38.3 versus 17.7 events per 1,000 patient-years, hazard ratio 2.1, 95% CI 1.37 to 3.20 after adjustment for risk factors. Secondary end-points also occurred more frequently in the NSVT-group. A shorter-term follow-up revealed similar event rates for the primary outcome; 47.5 versus 21.2 events per 1,000 patient-years, hazard ratio 1.9, 95% CI 0.69 to 5.24. Besides stroke other secondary end-points occurred more frequently in the short-term follow-up. The prognosis in subjects with NSVT was not dependent of the length of the VT. In conclusion, incidental asymptomatic NSVT on Holter-recording in subjects without apparent or manifest structural heart disease is associated with increased risk of mortality and cardiovascular events, however the increased risk is not imminent but with a slow and steady pace over time.

Cycle length of nonsustanied ventricular tachycardias among ICD patients: implications on subsequent appropriate therapies

Background

ICD patients with episodes of nonsustained ventricular tachycardias (NSVT) are at risk of appropriate therapies. However, the relationship between the cycle length (CL) of such NSVTs and the subsequent incidence of appropriate interventions is unknown.

Methods

416 ICD patients with LVEF < 45% were studied. ICD programming was standardized. NSVT was defined as any VT of 5 or more beats at ≥ 150 bpm occurred in the first 6 months after implantation that terminated spontaneously and was not preceded by any appropriate therapy. The mean follow-up was 41 ± 27 months.

Results

We analyzed 2201 NSVTs (mean CL = 323 ms) that occurred in 250 patients; 111 of such episodes were fast (CL ≤ 300 ms). Secondary prevention (HR = 1.7; p < 0.001), number of NSVT episodes (HR = 1.05; 95% CI 1.04–1.07; p < 0.001) and beta-blocker treatment (HR = 0.7; p = 0.04) were independent predictors of appropriate interventions; however, the mean CL of NSVTs was not (p = 0.6). There was a correlation between the mean CL of NSVTs and the CL of the first monomorphic VT: r = 0.88; p < 0.001. This correlation was especially robust in individuals with > 5 NSVTs (r = 0.97; p < 0.001), with an agreement between both values greater than 95%. Patients with any fast NSVT experienced a higher incidence of VF episodes (26%) compared to those without NVSTs (3%) or with only slow NSVTs (7%); p < 0.001.

Conclusions

Unlike the burden, the CL of NSVTs is not a predictor of subsequent appropriate interventions. However, there is a close relationship between the CL of NSVTs and that of arrhythmias that will later lead to appropriate therapies.

Risk factors for ventricular tachyarrhythmic events in patients without left bundle branch block who receive cardiac resynchronization therapy

INTRODUCTION

Cardiac resynchronization therapy (CRT) may be pro-arrhythmic in patients with non-left bundle branch block (non-LBBB). We hypothesized that combined assessment of risk factors (RF) for ventricular tachyarrhythmias (VTAs) can be used to stratify non-LBBB patients for CRT implantation.

METHODS

The study comprised 412 non-LBBB patients from MADIT-CRT randomized to CRT-D (n = 215) versus ICD only (n = 197). Best-subset regression analysis was performed to identify RF associated with increased VTA risk in CRT-D patients without LBBB. The primary end point was first occurrence of sustained VTA during follow-up. Secondary end points included VTA/death and appropriate shock.

RESULTS

Four RFs were associated with increased VTA risk: blood urea nitrogen >25mg/dl, ejection fraction <20%, prior nonsustained VT, and female gender. Among CRT-D patients, 114 (53%) had no RF, while 101 (47%) had ≥1 RF. The 4-year cumulative probability of VTA was higher among those with ≥1 RF compared with those without RF (40% vs. 14%, p < .001). Multivariate analysis showed that in patients without RF, treatment with CRT-D was associated with a 61% reduction in VTA compared with ICD-only therapy (p = .002), whereas among patients with ≥1 RF, treatment with CRT-D was associated with a corresponding 73% (p = .025) risk increase. Consistent results were observed when the secondary end points of VTA/death and appropriate ICD shocks were assessed.

CONCLUSION

Combined assessment of factors associated with increased risk for VTA can be used for improved selection of non-LBBB patients for CRT-D.

Effect of angiotensin/neprilysin inhibition on ventricular repolarization and clinical arrhythmogenesis

Background: The most common reason for sudden cardiac death in heart failure is malign ventricular arrhythmias. LCZ 696 improves hospitalization and sudden cardiac death outcomes in heart failure, however mechanisms in preventing sudden cardiac death are still unknown. There is little information available assessing effect of LCZ 696 on Tp-e interval and related calculations. In this study, we aimed to investigate the impact of Sacubitril/valsartan therapy on Tp-e interval, Tp-e/QT ratio and Tp-e/QTc ratio in heart failure patients and its reflections on clinical arrhythmogenesis. Methods: The study was designed as a prospective observational fashion. 265 patients with implantable cardioverter-defibrillator (ICD), who were on regular follow up at Samsun Training and Research Hospital Outpatient Heart Failure Clinic, were validated for the study. Clinical, echocardiographic, electrocardiogram and device data before initiation and six months after dose optimizing were obtained. Results: Stroke volume, cardiac output and ejection fraction significantly improved after LCZ 696 treatment. T wave related parameters, QT and QTC intervals significantly diminished. Furthermore, there was a negative correlation between baseline Tp-e interval duration and the absolute percentile increase of stroke volume(r:-0.234, p: 0.042) and cardiac output (r: -0.240, p: 0.037). Conclusion: In our study, switching Renin-Angiotensin-Aldosterone-System inhibitor with Angiotensin receptor/neprilysin inhibitor was associated with increase in left ventricle performance and decrease of sustained ventricular arrhythmias that required ICD shocks. These positive findings were accompanied by improvements in surface electrocaridogram changes such as Tp-e and related indices.

Clinical significance of precedent asymptomatic non-sustained ventricular tachycardias on subsequent ICD interventions and heart failure hospitalization in primary prevention ICD patients

Background

The prognostic implications of non-sustained ventricular tachycardia (NSVT) and their significance as therapeutic targets in patients without prior sustained ventricular arrhythmias remain undetermined. The aim of this study was to investigate the prognostic significance of asymptomatic NSVT in patients who had primary prevention implantable cardioverter-defibrillator (ICD) implantation due to ischemic or non-ischemic cardiomyopathy (ICM, NICM).

Methods

We enrolled 157 consecutive primary prevention ICD patients without previous appropriate ICD therapy (AIT). Patients were allocated to two groups depending on the presence or absence of NSVT in a 6-month period prior to enrollment. The incidence of AIT and unplanned hospitalization due to decompensated heart failure (HF) were assessed during follow-up.

Results

In 51 patients (32%), precedent NSVT was documented. During a median follow-up of 1011 days, AIT occurred in 36 patients (23%) and unplanned HF hospitalization was observed in 32 patients (20%). In precedent NSVT patients, the incidence of AIT and unplanned HF hospitalization was significantly higher as compared to patients without precedent NSVT (AIT: 29/51 [57%] vs. 7/106 [7%], P < 0.001, log-rank; HF hospitalization: 16/51 [31%] vs. 16/106 [15%], P = 0.043, log-rank). Cox-regression demonstrated that precedent NSVT independently predicted AIT (P < 0.0001). In subgroup analyses, precedent NSVT predicted AIT in both ICM and NICM (P < 0.0001, P = 0.020), but predicted HF hospitalization only in patients with ICM (P = 0.0030).

Conclusions

Precedent non-sustained VT in patients with primary prevention ICDs is associated with subsequent appropriate ICD therapies, and is an independent predictor of unplanned heart failure hospitalizations in patients with ischemic cardiomyopathy.

Predictive value of rapid-rate non-sustained ventricular tachycardia in the occurrence of appropriate implantable cardioverter-defibrillator therapy

PURPOSE

Rapid-rate non-sustained ventricular tachycardia (RR-NSVT) that meets detection criteria but terminates itself before the delivery of implantable cardioverter-defibrillator (ICD) therapy is not rare in routine ICD interrogation. Whether sustained ventricular tachycardia/fibrillation will occur in a short time after RR-NSVT has not been fully elucidated.

METHODS

Clinical features and follow-up data of 828 ICD patients with home monitoring were retrospectively collected. RR-NSVT characteristics and time interval between the first episode of RR-NSVT and subsequent appropriate ICD therapy were analyzed.

RESULTS

During a mean follow-up of 44.75 ± 20.87 months, 335 episodes of RR-NSVT were documented in 145 patients. A total of 119 patients had both RR-NSVT and appropriate ICD therapy. In multivariate COX regression models, RR-NSVT was an independent predictor of appropriate ICD therapy (HR 7.599, 95%CI 5.926-9.745, P < 0.001), appropriate shock (HR 6.222, 95%CI 4.667-8.294, P < 0.001), and all-cause mortality (HR 2.156, 95%CI 1.499-3.099, P < 0.001). Appropriate ICD therapy was administered after the first RR-NSVT episode in 101 patients, with a median interval of 21 days. Compared to RR-NSVT with appropriate ICD therapy occurring beyond 21 days, RR-NSVT within 21 days prior to appropriate ICD therapy had a longer median duration time (14 s vs. 12 s, P = 0.013), but without significant difference in mean RR interval at initial detection and mean RR interval after episode termination.

CONCLUSIONS

Rapid-rate non-sustained VT was an independent predictor of appropriate ICD therapy and all-cause mortality. The presence of RR-NSVT should be considered a possible herald of more serious cardiac events in ICD patients.

Prognostic role of non-sustained ventricular tachycardia detected with remote interrogation in a pacemaker population

Background

Non-sustained ventricular tachycardia (NSVT) can occur asymptomatically and can be incidentally detected in the internal records of pacemakers (PM). The clinical value of NSVT in the population of PM patients is still uncertain.

Our aim was to assess the prevalence of NSVT detected by remote PM control, to describe the clinical and demographic characteristics of patients with NSVT, and to assess the prognostic significance of NSVT in terms of both overall and cardiovascular mortality.

Methods

Consecutive patients followed with PM remote interrogations from September 2010 to December 2015 were included. The transmissions pertaining to the first 12 months of remote control were analysed and the patients were divided by those presenting NSVT and those without NSVT. The two groups were compared in terms of total mortality and cardiovascular mortality based on the administrative data provided by the regional administration of the Italian National Health System.

Results

The prevalence of NSVT in 408 patients (62% males, mean age 75.6; SD 10.6 years old) was 21% in a year. During a mean follow-up duration of 44 months, NSVT did not emerge as independently associated with overall mortality, but was associated with cardiovascular mortality in a competing risk regression model with older age, male gender, diabetes, chronic renal insufficiency, ischemic cardiomyopathy and chronic obstructive pulmonary disease.

Conclusions

We show that NSVT episodes recorded by remote control in a PM population are independently associated with cardiovascular mortality with possible implications for risk stratification and therapeutic options.

Clinical and Echocardiographic Predictors of Arrhythmias Detected With 24-Hour Holter Electrocardiography Among Hypertensive Heart Failure Patients in Nigeria

Background

Hypertensive heart failure (HHF) is the commonest form of heart failure in Nigeria. There is paucity of data in Nigeria on 24-hour Holter electrocardiography (24-HHECG) and important predictors of arrhythmias among HHF patients.

Objectives

To determine the 24-HHECG characteristics among HHF patients. To determine the clinical and echocardiographic predictors of arrhythmias detected using 24-HHECG among HHF patients.

Methods

A total of 100 HHF patients as well as 50 age-matched and sex-matched apparently healthy controls were prospectively recruited over a period of 1 year. They all had baseline laboratory tests, echocardiography, and 24-HHECG.

Results

Hypertensive heart failure patients had significantly higher counts of premature ventricular contractions (PVCs) than the controls (P ≤ .001). Ventricular tachycardia (VT) was recorded in 29% of HHF patients as compared with controls who had no VT on 24-HHECG. The standard deviation of all normal to normal sinus RR intervals over 24 hours (SDNN) was abnormally reduced among HHF patients when compared with controls (P = .046). There was positive correlation between atrial fibrillation (AF) and the following parameters: PVCs (r = .229, P = .015), New York Heart Association (NYHA) (r = .196, P = .033), and VT (r = .223, P = .018). Following multiple linear regression, left ventricular ejection fraction (LVEF) (P ≤ .001) and serum urea (P = .037) were predictors of PVCs among HHF patients. Serum creatinine (P ≤ .001), elevated systolic blood pressure (SBP) (P = .005), and PVCs (P ≤ .001) were important predictors of VT among HHF patients.

Conclusions

Renal dysfunction and reduced LVEF were important predictors of ventricular arrhythmias. High counts of PVCs and elevated SBP were predictive of the occurrence of VT among HHF patients. The NYHA class and ventricular arrhythmias have a significant positive correlation with AF. The SDNN is reduced in HHF patients.