Comparing outcome of patients with coronary artery disease and dilated cardiomyopathy in ICD and CRT recipients: data from the German DEVICE-registry

Comparison of Mortality and Readmission in Non-Ischemic Versus Ischemic Cardiomyopathy After Implantable Cardioverter-Defibrillator Implantation

Data is lacking on the contemporary risk of death and readmission following implantable cardioverter-defibrillator (ICD) implantation in patients with non-ischemic cardiomyopathies (NICM) compared with ischemic cardiomyopathies (ICM) in a large nationally representative cohort. We performed a retrospective cohort study using the National Cardiovascular Data Registry ICD Registry linked with Medicare claims from April 1, 2010 to December 31, 2013. We established a cohort of NICM and ICM patients with a left ventricular ejection fraction ≤35% who received a de novo, primary prevention ICD. We compared mortality and readmission using Kaplan-Meier curves and Cox proportional hazard regressions models. We also evaluated temporal trends in mortality. In 31,044 NICM and 68,458 ICM patients with a median follow up of 2.4 years, 1-year mortality was significantly higher in ICM patients (12.3%) compared with NICM (7.9%, p < 0.001). The higher mortality in ICM patients remained significant after adjustment for covariates (hazard ratio [HR] 1.40; 95% confidence interval [CI] 1.36 to 1.45), and was consistent in subgroup analyses. These findings were consistent across the duration of the study. ICM patients were also significantly more likely to be readmitted for all causes (adjusted HR 1.15, CI 1.12 to 1.18) and for heart failure (adjusted HR 1.25, CI 1.21 to 1.31). In conclusion, the risks of mortality and hospital readmission after primary prevention ICD implantation were significantly higher in patients with ICM compared with NICM which was consistent across all patient subgroups tested and over the duration of the study.

Differential effect of cardiac resynchronization therapy in patients with diabetes mellitus: a long-term retrospective cohort study

AIMS

Cardiac resynchronization therapy (CRT) has become an important therapy in patients with heart failure with reduced left ventricular ejection fraction (LVEF). The effect of diabetes on long-term outcome in these patients is controversial. We assessed the effect of diabetes on long-term outcome in CRT patients and investigated the role of diabetes in ischaemic and non-ischaemic cardiomyopathy.

METHODS AND RESULTS

All patients undergoing CRT implantation at our institution between November 2000 and January 2015 were enrolled. The study endpoints were (i) a composite of ventricular assist device (VAD) implantation, heart transplantation, or all-cause mortality; and (ii) reverse remodelling (improvement of LVEF ≥ 10% or reduction of left ventricular end-systolic volume ≥ 15%). Median follow-up of the 418 patients (age 64.6 ± 11.6 years, 22.5% female, 25.1% diabetes) was 4.8 years [inter-quartile range: 2.8;7.4]. Diabetic patients had an increased risk to reach the composite endpoint [adjusted hazard ratio (aHR) 1.48 [95% CI 1.12-2.16], P = 0.041]. Other factors associated with an increased risk to reach the composite endpoint were a lower body mass index or baseline LVEF (aHR 0.95 [0.91; 0.98] and 0.97 [0.95; 0.99], P < 0.01 each), and a higher New York Heart Association functional class or creatinine level (aHR 2.14 [1.38; 3.30] and 1.04 [1.01; 1.05], P < 0.05 each). Early response to CRT, defined as LVEF improvement ≥ 10%, was associated with a lower risk to reach the composite endpoint (aHR 0.60 [0.40; 0.89], P = 0.011). Reverse remodelling did not differ between diabetic and non-diabetic patients with respect to LVEF improvement ≥ 10% (aHR 0.60 [0.32; 1.14], P = 0.118). However, diabetes was associated with decreased reverse remodelling with respect to a reduction of left ventricular end-systolic volume ≥ 15% (aHR 0.45 [0.21; 0.97], P = 0.043). In patients with ischaemic cardiomyopathy, survival rates were not significantly different between diabetic and non-diabetic patients (HR 1.28 [0.83-1.97], P = 0.101), whereas in patients with non-ischaemic cardiomyopathy, diabetic patients had a higher risk of reaching the composite endpoint (HR 1.65 [1.06-2.58], P = 0.027). The latter effect was dependent on other risk factors (aHR 1.47 [0.83-2.61], P = 0.451). The risk of insulin-dependent patients was not significantly higher than in patients under oral antidiabetic drugs (HR 1.55 [95% CI 0.92-2.61], P = 0.102).

CONCLUSIONS

Long-term follow-up revealed diabetes mellitus as independent risk factor for all-cause mortality, heart transplantation, or VAD in heart failure patients undergoing CRT. The detrimental effect of diabetes appeared to weigh heavier in patients with non-ischaemic compared with ischaemic cardiomyopathy.

Increased mortality and ICD therapies in ischemic versus non-ischemic dilated cardiomyopathy patients with cardiac resynchronization having survived until first device replacement

INTRODUCTION

Cardiac resynchronization therapy combined with an implantable cardioverter defibrillator (CRT-D) is widely applied in heart failure patients. Sufficient data on arrhythmia and defibrillator therapies during long-term follow-up of more than 4 years are lacking and data on mortality are conflicting. We aimed to characterize the occurrence of ventricular arrhythmia, respective defibrillator therapies and mortality for several years following CRT-D implantation or upgrade.

MATERIAL AND METHODS

Eighty-eight patients with ischemic (ICM) or non-ischemic dilated cardiomyopathy (DCM) and at least one CRT-D replacement were included in this study and analyzed for incidence of non-sustained ventricular tachycardia (NSVT), defibrillator shocks, anti-tachycardia pacing (ATP) and mortality.

RESULTS

ICM was the underlying disease in 59%, DCM in 41% of patients. During a mean follow-up of 76.4 ±24.8 months the incidence of appropriate defibrillator therapies (shock or ATP) was 46.6% and was elevated in ICM compared to DCM patients (57.7% vs. 30.6%, respectively; p = 0.017). Kaplan-Meier analysis revealed significantly higher ICD therapy-free survival rates in DCM patients (p = 0.031). Left ventricular ejection fraction, NSVT per year and ICM (vs. DCM) were independent predictors of device intervention. The ICM patients showed increased mortality compared to DCM patients, with cumulative all-cause mortality at 9 years of follow-up of 45.4% and 10.6%, respectively. Chronic renal failure, peripheral artery disease and chronic obstructive pulmonary disease were independent predictors of mortality.

CONCLUSIONS

The clinical course of patients with ICM and DCM treated with CRT-D differs significantly during long-term follow-up, with increased mortality and incidence of ICD therapies in ICM patients.

Prevalence of non-acute ischaemic cardiomyopathy in a Pakistani cohort

Heart failure with reduced left ventricular ejection fraction (HFrEF) is a frequently encountered clinical scenario. Coronary angiography (CAG) is usually performed to assess obstructive epicardial coronary artery disease (CAD) and the resultant ischaemia as causes of HFrEF.

OBJECTIVES

To determine the frequency of obstructive CAD (OCAD) in patients with HFrEF and its independent predictors and outcomes.

METHODS

Retrospective observational study in Tabba Heart Institute on patients who underwent CAG during the past 4 years. Patients with prior known CAD or revascularisation were excluded. OCAD was defined as per the criteria from Felker et al. Regression modelling was performed to evaluate the predictors of OCAD. Survival was compared between the groups using the log rank test.

RESULTS

Out of 2235 patients who underwent CAG, 260 had HFrEF as a primary indication for CAG and, of these, 119 (45.8%) had OCAD. Major predictors of OCAD were age >50 years at presentation (OR 2.0, 95% CI 1.1 to 3.7), presence of chest pain (OR 4.3, 95% CI 2.3 to 8.1), family history of premature CAD (OR 2.8, 95% CI 1.3 to 5.9) and utilisation of non-invasive (NIV) stress testing before CAG (OR 3.6, 95% CI 1.8 to 7.1). Survival was significantly lower (log rank p<0.001) in patients with OCAD with no revascularisation compared with OCAD with revascularisation or those who had non-obstructive CAD, and the latter two groups had comparable survival.

CONCLUSIONS

OCAD is detected in nearly half of the patients with reduced left ventricular systolic function undergoing CAG. Clinical judgement based on thorough history and use of NIV stress testing can help in appropriate patient selection for this test.

A larger vectorcardiographic QRS area is associated with left bundle branch block and good prognosis in patients with cardiac resynchronization therapy

BACKGROUND

The association between the vectorcardiographic QRS area, bundle branch pattern and clinical long-term prognosis in patients who have undergone cardiac resynchronization therapy (CRT) has been unclear.

METHODS

We enrolled 50 consecutive patients who underwent CRT. Vectorcardiograms were constructed from preprocedural digital 12-lead electrocardiograms using the inverse Dower method. The vectorcardiographic QRS area was defined as the root of the sum of the square in the integral between the ventricular deflection curve and the baseline from QRS beginning to end in leads X, Y, and Z. The primary endpoints were total mortality and admission due to heart failure.

RESULTS

The vectorcardiographic QRS area in left bundle branch block (N = 13), right bundle branch block (N = 13), interventricular conduction delay (N = 11) and pacemaker rhythm (N = 13) were 218 ± 99, 97 ± 44, 90 ± 40, and 131 ± 58 μVs, respectively (ANOVA p < 0.001). During the mean follow-up period of 28 (2-86) months, 13 primary endpoints occurred. We divided patients into two groups: a large QRS area group (QRS area ≥114 μVs, N = 25) and a small QRS area group (QRS area <114 μVs, N = 25) by the median. The large QRS area group had a significantly lower rate of the primary endpoint compared with that of the small QRS area group (log rank 4.35, p = 0.037). The Cox regression analysis revealed that a QRS area <114 μVs was a significant predictor of the primary endpoint (HR 3.98, 95% CI 1.01-15.63, p = 0.048).

CONCLUSIONS

A larger preprocedural vectorcardiographic QRS area was associated with left bundle branch block and good prognosis in patients who underwent CRT.

Long-term outcomes after event-free cardioverter defibrillator implantation: comparison between patients discharged within 24 h and routinely hospitalized patients in the German DEVICE registry

Aims

To analyse the long-term safety of implantable cardioverter defibrillators (ICDs) in patients discharged within 24 h or after 2- 5-day hospitalization, respectively, after complication-free implantation, in circumstances of actual care.

Methods and results

Patients in the multicentre, nationwide German DEVICE registry were contacted 12-15 months after their first ICD implantation or device replacement. Data were collected on complications, potential arrhythmic events, syncope, resuscitation, ablation procedures, cardiac events, hospitalizations, heart failure status, change of medication, and quality of life. Of 2356 patients from 43 centres, 527 patients were discharged within 24 h and 1829 were hospitalized routinely for >24 h after complication-free implantations. The disease profiles and rates of co-morbidities were similar at baseline for both cohorts. During between 384 and 543 days of follow-up, there were no significant differences between the groups in terms of complications, hospitalizations, or quality of life. One-year rates of death were 4.5% in patients discharged early compared with 7.2% in hospitalized patients (hazard ratio 0.65; 95% confidence interval 0.42-1.02; P = 0.052). Rates of major adverse cardiovascular events or defibrillator events were not higher in patients discharged after 24 h. In both groups, a high rate of patients declared that they would opt for the procedure again in the same situation.

Conclusion

Data from a large-scale registry reflecting current day-to-day practice in Germany suggest that most patients can be discharged safely within 24 h of successful ICD implantation if there are no procedure-related events. Follow-up data up to 1.5 years after implantation did not raise long-term safety concerns.

Cardiac implant registries 2006-2016: a systematic review and summary of global experiences

OBJECTIVES

The importance of Cardiac Implant Registry (CIR) for ensuring a long-term follow-up in postmarket surveillance has been recognised and approved, but there is lack of consensus standards on how to establish a CIR. The aim of this study is to investigate the structure and key elements of CIRs in the past decade (2006-2016) and to provide recommendations on 'best practice' approaches.

SETTINGS AND PARTICIPANTS

A systematic search on CIR was employed in line with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. The following databases were searched: the PubMed (Medline), ScienceDirect and the Scopus database, EMBASE. After identifying the existing CIRs, an aggregative approach will be used to explore key elements emerging in the identified registries.

RESULTS

The following 82 registries were identified: 18 implantable cardioverterdefibrillator (ICD) registries, 7 cardiac resynchronisation therapy (CRT) registries, 5 pacemaker registries and 6 cardiovascular implantable electronic device registries which combined ICD, pacemaker and CRT implantation data; as well as 22 coronary stent registries and 24 transcatheteraortic heart valve implantation registries. While 71 national or local registries are from a single country, 44 are from European countries and 9 are located in USA. The following criteria have been summarised from the identified registries, including: registry working group, ethic issues, transparency, research objective, inclusion criteria, compulsory participation, endpoint, sample size, data collection basement, data collection methods, data entry, data validation and statistical analysis.

CONCLUSIONS

Registries provide a 'real-world' picture for patients, physicians, manufacturers, payers, decision-makers and other stakeholders. CIRs are important for regulatory decisions concerning the safety and therefore approval issues of the medical device; for payers CIRs provide evidence on the medical device benefit and drive the decision whether the product should be reimbursed or not; for hospitals CIRs' data are important for sound procurement decisions, and CIRs also help patients and their physicians to joint decision-making which of the products is the most appropriate.

Cardiac Resynchronization Therapy in Non-Ischemic Cardiomyopathy

Cardiac resynchronization therapy (CRT) is an established therapy for heart failure patients who remain symptomatic despite optimal medical therapy, have reduced left ventricular ejection fraction (<35%) and wide QRS duration (>120 ms), preferably with left bundle branch block morphology. The response to CRT depends on the cardiac substrate: presence of correctable left ventricular mechanical dyssynchrony, presence of myocardial fibrosis (scar) and position of the left ventricular pacing lead. Patients with non-ischemic cardiomyopathy have shown higher response rates to CRT compared with patients with ischemic cardiomyopathy. Differences in myocardial substrate may partly explain this disparity. Multimodality imaging plays an important role to assess the cardiac substrate and the pathophysiological determinants of response to CRT.

[In Germany too many ICD implantations are performed: pro]

Implantable cardioverter defibrillators (ICD) have undoubtedly developed into one of the most successful therapies in the field of cardiology over the last decades; however, a significant number of ICD operations are carried out in patients who do not benefit from ICD therapy despite significant left ventricular dysfunction. These patients can easily be identified. An ICD therapy does not prolong life in the setting of significant chronic kidney disease. In elderly patients the benefit of prophylactic ICD therapy is very small. Simple risk scores can identify other patients who do not benefit from this treatment. The number of ICD operations can also be significantly reduced by the use of devices with an extended longevity.

Comparison of the Effects of Epicardial and Endocardial Cardiac Resynchronization Therapy on Transmural Dispersion of Repolarization

BACKGROUND

Despite significant improvements in cardiac output and functional capacity with cardiac resynchronization therapy (CRT), incidence of sudden cardiac death still remains high. Reversal of physiological myocardial activation sequence during epicardial pacing increases the transmural dispersion of repolarization (TDR). The aim of this study was to compare the effects of endocardial and epicardial biventricular pacing on repolarization parameters in the same patient group.

METHODS

Seven patients who had transseptal endocardial left ventricle (LV) lead placement, in whom epicardial CRT had failed due to coronary sinus (CS) lead dislodgement after successful implantation, were admitted to the study. LV endocardial leads were implanted through the interatrial septum in a lateral position. Electrocardiograms (ECGs) were scanned before and after successful epicardial and endocardial biventricular pacing and analyzed using digital calipers. ECG markers of TDR (TpTe and TpTe/QT ratio) were measured and compared.

RESULTS

Baseline QRS durations (161.7 ± 15.9 ms vs 162.2 ± 17.8 ms, P = 0.95), TpTe values (107.1 ± 20.5 ms vs 108.5 ± 17.6 ms, P = 0.89), and TpTe/QT ratios (0.24 ± 0.05 vs 0.24 ± 0.03, P = 0.88) were similar before epicardial and endocardial CRT. QRS interval reduction was similar (-28.3 ± 11.6 ms vs -29.1 ± 11.4 ms, P = 0.89) in both groups. Compared to transseptal endocardial CRT, epicardial CRT was associated with a significant increase in TpTe (17.1 ± 19.5 ms vs -12.6 ± 18.9 ms, P = 0.01) and TpTe/QT ratio (0.03 ± 0.04 vs -0.02 ± 0.03, P = 0.04).

CONCLUSION

Transseptal LV endocardial pacing is associated with significant reduction in TDR characteristics compared to epicardial pacing in CRT. Further studies are warranted to determine whether these effects may contribute to reduction of arrhythmias in patients with CRT.

Reduction of inappropriate ICD therapies in patients with primary prevention of sudden cardiac death: DECREASE study

BACKGROUND

A significant number of patients with an implantable cardioverter/defibrillator (ICD) for primary prevention receive inappropriate shocks. Previous studies have reported a reduction of inappropriate therapies with simple modifications of ICD detection settings, however, inclusion criteria and settings varied markedly between studies. Our aim was to investigate the effect of raising the ICD detection zone in the entire primary prevention ICD population.

METHODS AND RESULTS

543 patients receiving an ICD for primary prevention were randomized to either conventional or progressive ICD programming. The detection rate was programmed at 171 bpm for ventricular tachycardia (VT) and 214 bpm for ventricular fibrillation (VF) in the Conventional group and 187 bpm for VT and 240 bpm for VF in the Progressive group. 43 % of patients received single-chamber and 57 % dual-chamber detection devices (DDD-ICD 19 %; CRT-D 38 %). The primary endpoint consisted of inappropriate therapies and untreated VT/VF. The primary endpoint was reached in 35 patients (13 %) in the Conventional group and 17 patients (6 %) in the Progressive group (p = 0.004). Progressive ICD programming led to significantly fewer amount of patients with ICD therapies (26 vs. 14 %; p < 0.001) and shocks (11 vs. 5 %; p = 0.023) compared to conventional ICD programming. Sub-analyses showed the greatest reduction of inappropriate therapies and shocks in dual-chamber detection devices with progressive compared to single-chamber detection devices with conventional ICD programming (p < 0.001).

CONCLUSIONS

Progressive ICD programming reduces the number of inappropriate therapies and shocks in a broad primary prevention ICD population particularly in combination with dual-chamber detection algorithms.

CLINICAL TRIAL REGISTRATION

http://clinicaltrials.gov ; ClinicalTrials.gov identifier NCT01217528.

Outcome of prolonged QRS interval in dilated cardiomyopathy: role of implantable cardioverter-defibrillators on mortality

AIM

The main objectives of this study were to investigate the relationship between prolonged QRS interval and its prognosis in patients with dilated cardiomyopathy (DCM), and to determine the effects of cardiac pacing with an implantable cardioverter-defibrillator (ICD) on mortality in patients with a QRS width > 150 ms.

METHODS

We retrospectively queried the healthcare enterprise data warehouse and the patient medical records from January 2007 to December 2012 for 1453 cases of DCM at a university- affiliated hospital. Of the 1453 cases, 989 patients were included in the final analyses. Primary outcome variable was all-cause mortality.

RESULTS

Of the 989 patients, 20% (n = 198) of the patients had a QRS width > 150 ms. Compared with patients who had a QRS < 120 ms, patients with a QRS > 150 ms had significantly higher rates of death (p < 0.001). Among the subgroup of 198 patients who had a QRS width > 150 ms, survival (84.3%, n = 75) was significantly higher (p < 0.001) in patients with a pacemaker inserted compared with those (45.0%, n = 49) who had not been paced.

CONCLUSIONS

Prolonged QRS interval is significantly associated with a higher rate of mortality. However, we believe that cardiac pacing with an ICD in such patients can significantly improve outcomes.

Effects of cardiac resynchronization therapy on left ventricular remodeling and dyssynchrony in patients with left ventricular noncompaction and heart failure

Left ventricular noncompaction (LVNC) is a rare cardiomyopathy with high incidence of heart failure (HF). It is unclear whether LVNC patients with desynchronized HF would benefit from cardiac resynchronization therapy (CRT). In order to evaluate the effect of CRT on LVNC, this study explored left ventricular (LV) remodeling and mechanical synchronicity before and after CRT in LVNC patients, and compare with that in idiopathic dilated cardiomyopathy (DCM) patients. We collected 15 LVNC and 30 matched DCM patients. All the patients underwent clinical evaluation,electrocardiogram and echocardiography before CRT and ≥6 months later. LV response was defined as ≥15 % decrease in LV end-systolic volume (LVESV). Longitudinal synchronicity was quantified by YU-index using tissue Doppler imaging. The time delay of peak radial strain from anteroseptal to posterior wall, which derived from speckle tracking imaging, was used to quantify radial synchronicity. In LVNC group, LV ejection fraction increased from 27.6 ± 5.5 to 39.1 ± 7.0 % (P < 0.01) during follow-up, but LV volumes did not change significantly (both P > 0.05). Five LVNC patients (33.3 %) responded to CRT, and all of them were super-responders (reduction in LVESV > 30 %). In addition, the number of noncompacted segments and the thickness ratio of noncompacted to compacted myocardium decreased (both P < 0.05). Inter-ventricular, longitudinal and radial intra-ventricular dyssynchrony also reduced significantly (all P < 0.05). Compared with DCM group, there was no significant difference in LV response rate (33.3 vs. 60.0 %, P = 0.092), improvement of LV function and dyssynchrony index (all P < 0.05). In conclusion, CRT improved heart function, morphology and mechanical dyssynchrony in LVNC patients.

Hotline update of clinical trials and registries presented at the American College of Cardiology Congress 2014

This article provides information and commentaries on trials which were presented at the Hotline and Clinical Trial Update Sessions during the Late Breaking Clinical Trial Sessions at the 63rd annual meeting of the American College of Cardiology in Washington, USA, from 29th to 31st March 2014. This article gives an overview on a number of novel clinical trials in the field of cardiovascular medicine, which were presented. Comprehensive summaries have been generated from the oral presentation and the webcasts of the American College of Cardiology, similar to as previously reported and should provide the readers with the most comprehensive information of relevant publications. The discussed studies are US CoreValve, Choice, Symplcity-HTN-3, GRS, ZEUS, GIPS-III, HEAT-PPCI, COPR-2, MSC-HF, POISE-2, SIRS. The data were presented by leading experts in the field.