Prognostic significance of nonsustained ventricular tachycardia in patients receiving cardiac resynchronization therapy for primary prevention: Analysis of the Japan cardiac device treatment registry database

A novel prediction model for survival in individual patients with cardiac resynchronization therapy with a defibrillator: Analysis of the new Japan cardiac device treatment registry database

Background

Accurate prediction for survival in individualized patients with cardiac resynchronization therapy with a defibrillator (CRT-D) is difficult.

Methods

We analyzed the New Japan cardiac device treatment registry (JCDTR) database to develop a survival prediction model for CRT-D recipients.

Results

Four hundred and eighty-two CRT-D recipients, at the implantation year 2018-2021, with a QRS width ≥120 ms and left ventricular ejection fraction (LVEF) ≤35% at baseline, were analyzed. During an average follow-up of 21 ± 10 months, death occurred in 66 of 482 CRT-D patients (14%). A prediction model estimating annual survival probability was developed using Cox regression with internal validation. With seven explanation predictors (age >75 years, serum creatinine >1.4 mg/dL, blood hemoglobin <12 g/dL, heart rate ≥90/min, LVEF, prior NSVT, and QRS width <150 ms), the model distinguished patients with and without all-cause death, with an optimism-corrected C-statistics of 0.766, 0.764, and 0.768, and calibration slope of 1.01, 1.00, and 1.00 at 1 year, 2 years, and 3 years. Additionally, we have devised the calculator of survival probability for individual CRT-D recipients.

Conclusions

Using routine available variables, we have developed a survival prediction model for individual CRT-D recipients.

Cardiac resynchronization therapy with a defibrillator in non-ischemic and ischemic patients for primary and secondary prevention of sudden cardiac death: Analysis of the Japan cardiac device treatment registry database

Background

Panoramic studies in patients with cardiac resynchronization therapy with a defibrillator (CRT-D) focusing on the etiology and indication are scarce. Besides, a controversy exists regarding requirement of a defibrillator in non-ischemic patients for primary prevention with CRT.

Methods

Annual trends of de novo CRT-D implantations from 2011 to 2020 and outcomes of those between January 2011 and August 2015 were analyzed from the Japan cardiac device treatment registry (JCDTR) and New JCDTR database.

Results

From 2011 to 2020, 8062 CRT-D recipients were registered, whose dominant indication was primary prevention of sudden cardiac death with a steady rate of about 70%. There was no significant temporal change of the proportion of non-ischemic patients being about 70% and 65% for primary and secondary prevention, respectively. Non-ischemic patients for primary prevention were associated with increased odds of appropriate ICD therapy [adjusted hazard ratio (aHR): 1.66; 95% confidence interval (CI): 1.01-2.75; p = .047] and reduced odds of any death (aHR: 0.66; 95% CI: 0.44-0.99; p = .046) as compared to ischemic patients.

Conclusions

Proportion of non-ischemic etiology was much higher than that of ischemic one in the CRT-D cohort. Based on the higher odds of appropriate ICD therapy, non-ischemic patients for primary prevention appear to be prudently selected in Japan.

Ventricular arrhythmia events in heart failure patients with cardiac resynchronization therapy with or without a defibrillator for primary prevention

Background

It is uncertain whether cardiac resynchronization therapy with a defibrillator (CRT-D) provides better survival benefits than a CRT-pacemaker (CRT-P) in heart failure patients with a reduced ejection fraction (≦35%, HFrEF) treated with contemporary HF therapy.

Methods

We retrospectively analyzed the ventricular arrhythmia (VAs; sustained ventricular tachycardia/fibrillation) events in HFrEF patients who underwent CRT without a prior history of VAs or aborted sudden cardiac death before the CRT implantation. Between January/2010 and December/2020, a CRT device was implanted in 79 HFrEF patients (mean age: 69 ± 12 years, male: 57, ischemic cardiomyopathy: 16). CRT-D and CRT-P devices were implanted in 50 and 29 patients, respectively, at each physician's discretion. CRT-Ds were indicated in younger patients than were CRT-Ps (66 ± 12 vs. 73 ± 12 years, p = 0.03), but the gender distribution did not differ (female, 24% [12 of 50] vs. 35% [10 of 29], p = 0.44). The VA events during a median follow-up of 3.5-years (interquartile range [IQR]:1.6-5.5) and their predictors were analyzed.

Results

VA events occurred in 9 patients with CRT-Ds (18%) and one with a CRT-P (3%, p = 0.08). The VA event rate was significantly lower in patients without a prior non-sustained ventricular tachycardia (NSVT: ≥3 beats; rate, ≥120 bpm; lasting <30 s, HR 0.05; 95% CI 0.01-0.30; p < 0.01) and females (HR 0.11; 95% CI 0.01-0.93; p = 0.04). Of note, no female patients without a prior history of NSVT experienced VA events.

Conclusion

HFrEF CRT candidates without a prior history of NSVT and females may obtain less benefit from a primary preventive defibrillator indication.

Nonsustained Ventricular Tachycardia Is Independently Associated With Sustained Ventricular Arrhythmias in Nonischemic Dilated Cardiomyopathy

BACKGROUND

Spontaneous nonsustained ventricular tachycardia (NSVT) on Holter, VT inducibility during electrophysiology study, and late gadolinium enhancement (LGE) on cardiac magnetic resonance (CMR) have been associated with sustained ventricular arrhythmias (SVAs) in nonischemic dilated cardiomyopathy (DCM). This study aimed to analyze whether these parameters carry independent prognostic value for spontaneous SVA in DCM.

METHODS

Between 2011 and 2018, patients with the DCM clinical spectrum and documented SVA, suspected SVA, or considered to be at intermediate or high risk for SVA were enrolled in the prospective Leiden Nonischemic Cardiomyopathy Study. Patients underwent a comprehensive evaluation including 24-hour Holter, LGE-CMR, and electrophysiology study. Holters were assessed for the presence of NSVT (≥3 beats; rate, ≥120 bpm; lasting <30 s) and NSVT characteristics (coupling interval, duration, cycle length, morphology, regularity). Patients were followed at 6 to 12 monthly intervals.

RESULTS

Of all 115 patients (age, 59±12 years; 77% men; left ventricular ejection fraction, 33±13%; history of SVA, 36%; LGE in 63%; median LGE mass, 13 g; interquartile range, 8-23 g), 62 (54%) had NSVT on Holter, and sustained monomorphic VT was inducible in 34 of 114 patients (30%). NSVT was not associated with LGE on CMR or VT inducibility during electrophysiology study nor were its features (all P>0.05). During 4.0±1.8 years of follow-up, SVA occurred in 39 patients (34%). NSVT (HR, 4.47 [95% CI, 1.87-10.72]; P=0.001) and VT inducibility (HR, 3.08 [95% CI, 1.08-8.81]; P=0.036) were independently associated with SVA during follow-up. A bivariable model including only noninvasively acquired parameters also allowed identification of a high-risk subgroup (ie, those with both NSVT and LGE on CMR). The findings remained similar when only patients without prior SVA were included.

CONCLUSIONS

In patients with DCM, NSVT on Holter and VT inducibility during electrophysiology study predict SVA during follow-up independent of LGE on CMR. NSVTs may serve as an initiator, and sustained VT inducibility indicates the presence of the substrate for SVA in DCM. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT01940081.

CMR-Based Risk Stratification of Sudden Cardiac Death and Use of Implantable Cardioverter-Defibrillator in Non-Ischemic Cardiomyopathy

Non-ischemic cardiomyopathy (NICM) is one of the most important entities for arrhythmias and sudden cardiac death (SCD). Previous studies suggest a lower benefit of implantable cardioverter–defibrillator (ICD) therapy in patients with NICM as compared to ischemic cardiomyopathy (ICM). Nevertheless, current guidelines do not differentiate between the two subgroups in recommending ICD implantation. Hence, risk stratification is required to determine the subgroup of patients with NICM who will likely benefit from ICD therapy. Various predictors have been proposed, among others genetic mutations, left-ventricular ejection fraction (LVEF), left-ventricular end-diastolic volume (LVEDD), and T-wave alternans (TWA). In addition to these parameters, cardiovascular magnetic resonance imaging (CMR) has the potential to further improve risk stratification. CMR allows the comprehensive analysis of cardiac function and myocardial tissue composition. A range of CMR parameters have been associated with SCD. Applicable examples include late gadolinium enhancement (LGE), T1 relaxation times, and myocardial strain. This review evaluates the epidemiological aspects of SCD in NICM, the role of CMR for risk stratification, and resulting indications for ICD implantation.

Current status and role of programmed ventricular stimulation in patients without sustained ventricular arrhythmias and reduced ejection fraction: Analysis of the Japan cardiac device treatment registry database

BACKGROUND

The aim of this study was to clarify the current status and role of programmed ventricular stimulation in patients without sustained ventricular arrhythmias and reduced left ventricular ejection fraction (LVEF).

METHODS

The follow-up data of the Japan cardiac device treatment registry (JCDTR) was analyzed in 746 patients with LVEF ≦35% and no prior history of sustained ventricular arrhythmias who underwent de novo implantable cardioverter-defibrillator (ICD) or cardiac resynchronization therapy with a defibrillator (CRT-D) implantation between January 2011 and August 2015.

RESULTS

Electrophysiological study (EPS) with programmed ventricular stimulation had been performed before the device implant in 118 patients (15.8%, EPS group). During the mean follow-up of 21 ± 12 months, the rate of freedom from any death and appropriate defibrillator therapy was not significantly different between EPS group (n = 118) and No EPS group (n = 628). NYHA class II-IV, and QRS duration were negatively associated with performing EPS. Among patients in the EPS group, the rate of ventricular tachycardia (VT)/ventricular fibrillation (VF) induction was 48%. The inducibility was not a predictor of appropriate defibrillator therapy, whereas BNP ≧535 pg/mL and no use of amiodarone were significantly associated with a risk of the appropriate therapy.

CONCLUSION

EPS for induction of VT/VF had been performed in about 16% of patients with reduced LVEF before primary prevention ICD/CRT-D implantation. Elevated BNP levels and no use of amiodarone, but not inducibility of VT/VF, appeared to be associated with appropriate defibrillator therapy in these populations.

Rapid-rate nonsustained ventricular tachycardias in high-risk dilated cardiomyopathy patients

AIMS

Nonsustained ventricular tachycardia (NSVT) occurs frequently in patients with dilated cardiomyopathy (DCM), especially in high-risk patients. The role of rapid-rate NSVT (RR-NSVT) documented by an implantable cardioverter-defibrillator (ICD) in DCM patients has not been fully explored. This study aimed to determine the relationship between RR-NSVT and the occurrence of ventricular tachyarrhythmias (VTAs) in DCM patients with ICD.

METHODS

From December 2000 to December 2017, 136 DCM patients received ICD or cardiac resynchronization therapy defibrillator (CRT-D) implantation for primary or secondary prevention of VTAs. Based on the occurrence of documented RR-NSVT, patients were classified into RR-NSVT (-) or RR-NSVT (+) groups.

RESULT

During the median follow-up of 4.5 years, 50.0% (68/136) patients experienced ≥1 episode, and 25.0% (34/136) patients experienced ≥3 episodes of RR-NSVT. Event-free survival for VTAs was significantly higher in the RR-NSVT (-) group, whereas those for heart failure admission and cardiovascular mortality were comparable between groups. In the multivariate Cox regression analysis, any RR-NSVT showed a positive association with the occurrence of VTAs (hazard ratio: 5.087; 95% confidence interval: 2.374-10.900; P < .001). In RR-NSVT (+) patients, a cluster (≥3 times/6 months) and frequent pattern (≥3 runs/day) of RR-NSVT were observed in 42.6% (29/68) and 30.9% (21/68) patients, respectively, who showed further increased incidence of VTAs.

CONCLUSION

In DCM patients with ICD/CRT-D, 50.0% patients experienced at least one episode of RR-NSVT. RR-NSVT documentation showed a positive association with subsequent occurrence of VTAs, suggesting the importance of constructive arrhythmia management for patients with RR-NSVT.

Trends in the use of implantable cardioverter-defibrillator and cardiac resynchronization therapy device in advancing age: Analysis of the Japan cardiac device treatment registry database

BACKGROUND

Trends of de novo implantation of cardiac implantable electronic devices (CIEDs) including implantable cardioverter-defibrillator (ICD) and cardiac resynchronization therapy with a defibrillator (CRT-D) or pacemaker (CRT-P) in advancing age are unknown.

METHODS

Analysis of data from the Japan cardiac device treatment registry (JCDTR) with an implantation date between January 2006 and December 2016 was performed focusing on advancing age of ≧75 years.

RESULTS

The cohort included 17 564 ICD, 9470 CRT-D and 1087 CRT-P recipients for de novo implantation. The rate of patients ≧75 years of age increased from 17.1% to 20.5% in ICD implantation (P = .052), from 19.7% to 30.0% in CRT-D implantation (P < .0001), and from 40.0% to 64.0% in CRT-P implantation (P = .17). There was an apparent increase in the percentage of nonischemic patients aged ≧75 years receiving ICD (10.9% in 2006 to 16.4% in 2016, P = .0008) and CRT-D (17.1% in 2006 to 27.8% in 2016, P = .0001). The implantation for primary prevention ICD (P = .059) and CRT-D (P = .012) was also associated with a temporal increase in the percentage of patients aged ≧75 years.

CONCLUSIONS

Proportion of patients ≧75 years of age for de novo CIED implantation gradually increased from 2006 to 2016, presumably because of the growing number of nonischemic cardiomyopathy and heart failure patients requiring primary prevention of sudden cardiac death.

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.

Hyperglycemia and risk of ventricular tachycardia among patients hospitalized with acute myocardial infarction

Background

Little is known about the association of hyperglycemia with the development of ventricular tachycardia (VT) in patients hospitalized with acute myocardial infarction (AMI) which we examined in the present study. The objectives of this community-wide observational study were to examine the relation between elevated serum glucose levels at the time of hospital admission for AMI and occurrence of VT, and time of occurrence of VT, during the patient’s acute hospitalization.

Methods

We used data from a population-based study of patients hospitalized with AMI at all central Massachusetts medical centers between 2001 and 2011. Hyperglycemia was defined as a serum glucose level ≥ 140 mg/dl at the time of hospital admission. The development of VT was identified from physicians notes and electrocardiographic findings by our trained team of data abstractors.

Results

The average age of the study population was 70 years, 58.0% were men, and 92.7% were non-Hispanic whites. The mean and median serum glucose levels at the time of hospital admission were 171.4 mg/dl and 143.0, respectively. Hyperglycemia was present in 51.9% of patients at the time of hospital admission; VT occurred in 652 patients (15.8%), and two-thirds of these episodes occurred during the first 48 h after hospital admission (early VT). After multivariable adjustment, patients with hyperglycemia were at increased risk for developing VT (adjusted OR = 1.48, 95% CI = 1.23–1.78). The presence of hyperglycemia was significantly associated with early (multivariable adjusted OR = 1.39, 95% CI = 1.11–1.73) but not with late VT. Similar associations were observed in patients with and without diabetes and in patients with and without ST-segment elevation AMI.

Conclusions

Efforts should be made to closely monitor and treat patients who develop hyperglycemia, especially early after hospital admission, to reduce their risk of VT.