Early procedure-related adverse events by gender in MADIT-CRT

Predicting long-term survival after de novo cardioverter-defibrillator implantation for primary prevention: A population based study

Background

Implantable cardioverter-defibrillators (ICDs) reduce the risk of sudden cardiac death in patients with left ventricular dysfunction. While short-term mortality benefit of ICD insertion has been established in landmark randomized controlled trials, little is known about the long-term outcomes of patients with ICDs in clinical practice. In this paper, we describe the long-term survival of patients following de novo ICD implantation for primary prevention in clinical practice and determine the factors which help predict survival after ICD implant.

Methods

Retrospective population-based study of all patients receiving a de novo ICD for primary prevention in Ontario, Canada from 2007 to 2011 using the Ontario ICD Database housed within ICES. Simple random selection was used to split the population into a derivation and internal validation cohort in a ratio of 2:1. Cox proportional hazards regression was used to determine predictors of interest and predict 10-year survival, model performance was assessed using calibration and validation.

Results

In the derivation cohort (n = 3399), mean age was 65.3 years (standard deviation [SD] = 11.0), 664 patients were female (19.5 %) and 2344 patients (69.0 %) had ischemic cardiomyopathy. Ten year survival was 45.7 % (95 % confidence interval [CI] 44.0 %-47.4 %). The final prediction model included age, sex, disease factors (ischemic vs nonischemic cardiomyopathy, left ventricular ejection fraction) and patient factors (symptoms, comorbidities), and biomarkers at the time of ICD assessment. This model had good discrimination and calibration in derivation (0.79, 95 % CI 0.77, 0.81) and validation samples (0.78, 95 % CI 0.76, 0.79).

Conclusions

A combination of demographic and clinical factors determined at baseline can be used to predict 10-year survival in patients with implantable cardioverter-defibrillators with good accuracy. Our findings help to identify individuals at risk of long-term mortality and may be useful in targeting future prevention strategies to enhance longevity in this high-risk population.

Gender and race-related disparities in the management of ventricular arrhythmias

Modern studies have revealed gender and race-related disparities in the management and outcomes of cardiac arrhythmias, but few studies have focused on outcomes for ventricular arrhythmias (VAs) such as ventricular tachycardia (VT) or ventricular fibrillation (VF). The aim of this article is to review relevant studies and identify outcome differences in the management of VA among Black and female patients. We found that female patients typically present younger for VA, are more likely to have recurrent VA after catheter ablation, are less likely to be prescribed antiarrhythmic medication, and are less likely to receive primary prevention ICD placement as compared to male patients. Additionally, female patients appear to derive similar overall mortality benefit from primary prevention ICD placement as compared to male patients, but they may have an increased risk of acute post-procedural complications. We also found that Black patients presenting with VA are less likely to undergo catheter ablation, receive appropriate primary prevention ICD placement, and have significantly higher risk-adjusted 1-year mortality rates after hospital discharge as compared to White patients. Black female patients appear to have the worst outcomes out of any demographic subgroup.

Hospital utilisation and the costs associated with complications of ICD implantation in a contemporary primary prevention cohort

Introduction

Implantation of an implantable cardioverter defibrillator (ICD) is standard care for primary prevention of sudden cardiac death. However, ICD-related complications are increasing as the population of ICD recipients grows.

Methods

ICD-related complications in a national DO-IT Registry cohort of 1442 primary prevention ICD patients were assessed in terms of additional use of hospital care resources and costs.

Results

During a median follow-up of 28.7 months (IQR 25.2–33.7) one or more complications occurred in 13.5% of patients. A complication resulted in a surgical intervention in 53% of cases and required on average 3.65 additional hospital days. The additional hospital costs were €6,876 per complication or €8,110 per patient, to which clinical re-interventions and additional hospital days contributed most. Per category of complications, infections required most hospital utilisation and were most expensive at an average of €22,892. The mean costs were €5,800 for lead-related complications, €2,291 for pocket-related complications and €5,619 for complications due to other causes. We estimate that the total yearly incidence-based costs in the Netherlands for hospital management of ICD-related complications following ICD implantation for primary prevention are €2.7 million.

Conclusion

Complications following ICD implantation are related to a substantial additional need for hospital resources. When performing cost-effectiveness analyses of ICD implantation, including the costs associated with complications, one should be aware that real-world complication rates may deviate from trial data. Considering the economic implications, strategies to reduce the incidence of complications are encouraged.

Sex Differences in Implantation and Outcomes of Cardiac Resynchronization Therapy in Real-World Settings: A Systematic Review of Cohort Studies

Background

Evidence from randomized trials is conflicting on the effects of cardiac resynchronization therapy (CRT) by sex, and differences in access are unknown. We examined sex differences in the implantation rates and outcomes in patients treated with CRT using cohort studies.

Methods

We followed a pre-specified protocol (International Prospective Register of Systematic Reviews [PROSPERO]: CRD42020204804). MEDLINE, Embase, and Web of Science were searched for cohort studies from January 2000 to June 2020 that evaluated the response to CRT in patients ≥ 18 years old and reported sex-specific information in any language.

Results

We included 97 studies (1,172,654 men and 486,553 women). Men received CRT more frequently than women (median ratio, 3.16; 25th to 75th interquartile range, 2.48-3.62). In the unadjusted analysis, men had a greater long-term all-cause mortality rate after CRT, compared with women (hazard ratio [HR], 1.50; 95% confidence interval [CI], 1.38-1.63; P < 0.001). Adjustment for confounders did not affect the strength or direction of association (HR, 1.45; 95% CI, 1.32-1.59; P < 0.001). Women achieved a greater rate of improvement in left ejection fraction compared with men (HR, 4.66; 95% CI, 4.23-5.13; P < 0.001). Men had a lower risk of a pneumothorax (relative risk, 0.21; 95% CI, 0.13-0.34; P < 0.001]); otherwise, there were no differences in complications.

Conclusions

We found in this large meta-analysis that men were more often implanted with CRT than women, yet men had a higher long-term all-cause mortality following CRT, compared with women, and smaller improvement in left ventricular ejection fraction. Reasons for this difference in implantation rates of CRT in real-world practice need to be investigated.

Response to cardiac resynchronisation therapy in men and women: a secondary analysis of the SMART-AV randomised controlled trial

OBJECTIVES

There is a controversy about whether both sexes' response to cardiac resynchronisation therapy (CRT) is similar. We aimed to assess a causal effect of sex on CRT response.

DESIGN

Secondary analysis of a randomised controlled trial (RCT) data. Doubly robust augmented-inverse-probability-weighted (AIPW) estimation of sex effect on CRT response.

SETTING

The SmartDelay Determined Atrioventricular (AV) Optimisation (SMART-AV) RCT.

PARTICIPANTS

The SMART-AV RCT enrolled New York Heart Association class III-IV patients with heart failure (HF) with left ventricular ejection fraction (LVEF) ≤35% despite optimal medical therapy and QRS duration ≥120 ms, in sinus rhythm. After exclusion of those with missing outcome or covariates, 741 participants (age 66±11 years; 33% female; 78% white; LVEF 28%±9%; 58% ischaemic cardiomyopathy; 75% left bundle branch block; left ventricular end-systolic volume index (LVESVI) 65±30 mL/m²) were included.

INTERVENTIONS

Implanted CRT defibrillator with randomly assigned AV delay as either (1) fixed at 120 ms, or (2) echocardiography-determined, or (3) SmartDelay algorithm-programmed.

OUTCOME

A composite of freedom from death and HF hospitalisation and a >15% reduction in LVESVI at 6 month post-CRT was the endpoint.

RESULTS

The primary endpoint was met by 337 patients (45.5%); 134 were women (55.6% response) and 203 were men (40.6% response); p<0.0001. After conditioning for 33 covariates that included baseline demographic, clinical, ECG, echocardiographic and biomarker characteristics, known predictors of CRT response, logistic regression showed a higher probability for composite CRT response for women versus men (OR 1.79; 95% CI 1.08 to 2.98; p<0.0001), whereas AIPW estimation showed no difference in CRT response (average treatment effect 0.88; 95% CI 0.41 to 1.89; p=0.739). After removing colliders from the model, both logistic regression (OR 1.00; 95% CI 0.69 to 1.44) and AIPW (ATE 1.06; 95% CI 0.96 to 1.16) reported similar results.

CONCLUSIONS

Both sexes' response to CRT is similar. Sex differences in HF substrate, treatment and comorbidities explain sex disparities in CRT outcomes.

TRIAL REGISTRATION NUMBER

ClinicalTrials.gov Identifier; NCT00677014.

Sex differences in CRT device implantation rates, efficacy, and complications following implantation: protocol for a systematic review and meta-analysis of cohort studies

INTRODUCTION

There is abundant evidence for sex differences in the diagnosis, implantation, and outcomes for cardiac resynchronization therapy (CRT) devices. Controversial data suggesting women are less likely to receive the device regardless of the greater benefit. The aim of this review is to assess sex differences in the implantation rate, clinical effectiveness, and safety of patients receiving CRT devices.

METHODS

We will conduct a systematic literature search of MEDLINE, Embase, and Web of Science to identify cohort studies that meet our eligibility criteria. Title and full text screening will be conducted in duplicate independently. Eligible studies report clinical effectiveness or safety of patients receiving CRT device while providing sex-disaggregated data. Implantation rate will be extracted from the baseline characteristics tables of the studies. The effectiveness outcomes include the following: all-cause death, hospitalization, peak oxygen consumption (pVO₂), quality of life (QoL), 6-min walk test, NYHA class reduction, LVEF, and heart failure hospitalization. The complication outcomes include the following: contrast-induced nephropathy, pneumothorax, pocket-related hematoma, pericardial tamponade, phrenic nerve stimulation, device infection, death, pulmonary edema, electrical storm, cardiogenic shock, and hypotension requiring resuscitation. Description of included studies will be reported in detail and outcomes will be meta-analyzed and presented using forest plots when feasible. Risk of bias will be assessed using the Newcastle-Ottawa Scale (NOS) by two review authors independently. GRADE approach will be used to assess the certainty of evidence.

DISCUSSION

The aim of this review is to determine the presence of differences in CRT implantation between women and men as well as differences in clinical effectiveness and safety of CRT after device implantation. Results from this systematic review will provide important insights into sex differences in CRT devices that could contribute to the development of sex-specific recommendations and inform policy.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42020204804.

Dutch Outcome in Implantable Cardioverter-Defibrillator Therapy: Implantable Cardioverter-Defibrillator-Related Complications in a Contemporary Primary Prevention Cohort

Background

One third of primary prevention implantable cardioverter‐defibrillator patients receive appropriate therapy, but all remain at risk of defibrillator complications. Information on these complications in contemporary cohorts is limited. This study assessed complications and their risk factors after defibrillator implantation in a Dutch nationwide prospective registry cohort and forecasts the potential reduction in complications under distinct scenarios of updated indication criteria.

Methods and Results

Complications in a prospective multicenter registry cohort of 1442 primary implantable cardioverter‐defibrillator implant patients were classified as major or minor. The potential for reducing complications was derived from a newly developed prediction model of appropriate therapy to identify patients with a low probability of benefitting from the implantable cardioverter‐defibrillator. During a follow‐up of 2.2 years (interquartile range, 2.0–2.6 years), 228 complications occurred in 195 patients (13.6%), with 113 patients (7.8%) experiencing at least one major complication. Most common ones were lead related (n=93) and infection (n=18). Minor complications occurred in 6.8% of patients, with lead‐related (n=47) and pocket‐related (n=40) complications as the most prevailing ones. A surgical reintervention or additional hospitalization was required in 53% or 61% of complications, respectively. Complications were strongly associated with device type. Application of stricter implant indication results in a comparable proportional reduction of (major) complications.

Conclusions

One in 13 patients experiences at least one major implantable cardioverter‐defibrillator–related complication, and many patients undergo a surgical reintervention. Complications are related to defibrillator implantations, and these should be discussed with the patient. Stricter implant indication criteria and careful selection of device type implanted may have significant clinical and financial benefits.

Novel two-lead cardiac resynchronization therapy system provides equivalent CRT responses with less complications than a conventional three-lead system: Results from the QP ExCELs lead registry

Introduction

The novel two‐lead cardiac resynchronization therapy (CRT)‐DX system utilizes a floating atrial dipole on the implantable cardioverter‐defibrillator lead, and when implanted with a left ventricular (LV) lead, offers a two‐lead CRT system with AV synchrony. This study compared complication rates and CRT response among subjects implanted with a two‐lead CRT‐DX system to those subjects implanted with a standard three‐lead CRT‐D system.

Methods and Results

A total of 240 subjects from the Sentus QP—Extended CRT Evaluation with Quadripolar Left Ventricular Leads postapproval study were selected to identify 120 matched pairs based on similar demographic characteristics using a Greedy algorithm. The complication‐free rate was evaluated as the primary endpoint. All‐cause mortality, heart failure hospitalizations, device diagnostic data, New York Heart Association (NYHA) class improvement, and defibrillator therapy were evaluated from clinical data, in‐office interrogations, and remote monitoring throughout the follow‐up period. Complication‐free survival favored the CRT‐DX group with 92.5% without a major complication compared to 85.0% in the CRT‐D cohort (P = .0495; 95% confidence interval: 0.1%‐14.9%) over a mean follow‐up of 1.3 and 1.4 years, respectively. Incidence of all‐cause mortality, heart failure hospitalizations, NYHA changes at 6 months postimplant, and percent of LV pacing during CRT therapy were similar in both device cohorts. Inappropriate shocks were more frequent in the CRT‐D cohort with 5.8% of subjects receiving an inappropriate shock vs 0.8% in the CRT‐DX cohort.

Conclusion

The results of this subanalysis demonstrate that the CRT‐DX system can provide similar CRT responses and significantly fewer complications when compared to a similar cohort with a conventional three‐lead CRT‐D system.

Utility of the Modified Frailty Index to Predict Cardiac Resynchronization Therapy Outcomes and Response

The aim of the present study was to investigate the utility of the modified frailty index (mFI) to predict outcomes in patients who underwent cardiac resynchronization therapy (CRT) device implantation. A retrospective cohort study of patients undergoing CRT implantation or upgrade over a 5-year period was performed. The relation between the preprocedural 11-component mFI and clinical outcomes including 1-year mortality, periprocedural and 30-day adverse events, 30-day readmission, length of hospitalization after procedure, and response to CRT defined by changes in left ventricular ejection fraction and end-diastolic volume were studied. Of 283 patients studied, 134 (47.3%) were classified as frail (mFI ≥3). Frailty was associated with an increased risk of 1-year mortality (hazard ratio 5.87, p = 0.033 in multivariate analysis), and increased frequency of adverse events (p = 0.013), 30-day readmission (p = 0.0077), and postprocedural length of stay ≥3 days (p = 0.0005). Frail patients had significantly less echocardiographic response to CRT compared with nonfrail patients with change in left ventricular ejection fraction 6% versus 12% (p = 0.004) and change in left ventricular end-diastolic volume -19.9 versus -43.3 ml (p = 0.006). In conclusion, frailty as assessed by the mFI is associated with an increase in 1-year mortality, adverse events, 30-day readmission, length of stay, and poorer response to CRT after implantation.

Sex Differences in Advanced Heart Failure Therapies

This in-depth review of sex differences in advanced heart failure therapy summarizes the existing literature on implantable cardioverter defibrillators, biventricular pacemakers, mechanical circulatory support, and transplantation with a focus on utilization, efficacy/clinical effectiveness, adverse events, and controversies. One will learn about the controversies regarding efficacy/clinical effectiveness of implantable cardioverter defibrillators and understand why these devices should be implanted in women even if there are sex differences in appropriate shocks. Individuals will learn about the sex differences with biventricular pacemakers with respect to ventricular remodeling and reduction in heart failure hospitalizations/mortality, as well as, possible mechanisms. We will demonstrate sex differences in heart transplantation and waitlist survival. Despite similar survival for women and men with left ventricular assist devices, there are sex differences in adverse events. These devices do successfully bridge women and men to transplant, yet women are less likely than men to have a left ventricular assist at time of listing and time of transplantation. Finally, one will learn about the concerns regarding poor outcome for men who receive female donor hearts and discover this may not be due to sex, but rather size. More research is needed to better understand sex differences and further improve advanced heart failure therapy for both women and men.

Occurrence, mortality and predictors of complicated cardiac perforation in patients with CRT-D: Based on the National Inpatient Sample registry

BACKGROUND

Cardiac Resynchronization Therapy Defibrillator (CRT-D) has been one of the most important therapies for patients with cardiomyopathy over the last decades. Cardiac perforation occurs infrequently but can be fatal. The occurrence of cardiac perforation after CRT-D implantation has not been studied well. The aim of study is to investigate the occurrence, mortality and predictors of cardiac perforation in patients receiving CRT-D during the index hospitalization.

METHODS

Data were obtained from the National Inpatient Sample, the largest all-player inpatient dataset in the United States. Patients who received CRT-D from 2002 to 2012 were identified using ICD-9 codes. Multivariate analyses were used to identify predictors of cardiac perforation. Complications including in-hospital death and cardiac perforation were identified using ICD-9 codes.

RESULTS

A total of 77,827 patients with CRT-D implantation were included into our analysis. After the CRT-D implantation, the in-hospital and rate of cardiac perforation was between 0.24 and 0.48% and had increased significantly (p = 0.02). Although occurrence of cardiac perforation is rare (0.32%), the mortality was 10.6% among those patients with cardiac perforation. In Multivariate analysis identified female as independent risk factors for cardiac perforation (OR: 2.628, 95% CI 1.926-3.585, p < 0.0001).

CONCLUSION

Despite rapid progress of the tools and skills for CRT-D implantation, the occurrence of cardiac perforation has not improved. While cardiac perforation is rare, it carries the highest rate of mortality, especially in female patients. Implanting physicians should be familiar with the comorbidities and patient demographics that put them at a higher risk for complications.

Sex-Related Procedural Aspects and Complications in CRT Survey II: A Multicenter European Experience in 11,088 Patients

OBJECTIVES

This study sought to compare sex difference for procedural aspects and complications in the European Society of Cardiology CRT Survey II, exploring whether adverse events were related to the type of CRT device implanted.

BACKGROUND

Sex-related differences in procedural aspects and complications in patients undergoing cardiac resynchronization therapy (CRT) implantation has not been explored in a real-life population.

METHODS

A post-hoc analysis of procedural data and complications in different sexes and factors associated with events was performed from data collected in the European Society of Cardiology CRT Survey II.

RESULTS

Of all patients (n = 11,088) included, 24.3% were women. The mean age (70 years of age) of male and female recipients was similar. Female patients more frequently had an idiopathic cardiomyopathy (67.4% vs. 44.1%) and fewer comorbidities, including atrial fibrillation (34.8% vs. 42.8%), diabetes (29.1% vs. 32.1%), chronic obstructive lung disease (10.3% vs. 12.6%), and renal failure (28.7% vs. 31.9%), compared with men. More women compared with men had a pacemaker (56.6% vs. 46.3%) and much less often an implantable cardioverter-defibrillator (CRT-D) (19.0% vs. 34.7%) implant. Periprocedural event rate was the highest in women with CRT with defibrillator (7.1% vs. 4.8% in men), followed by women with a CRT with pacing (5.5% vs. 4.4% in men). The higher periprocedural event rate in CRT-D women was attributable primarily to the occurrence of pneumothorax (1.4%), coronary sinus dissection (2.1%), and pericardial tamponade (0.3%). The rate of in-hospital major adverse events (6.0%) and complications necessitating reoperation (4.0%) was not different among sex and device type.

CONCLUSIONS

Women are more likely to experience adverse procedure-related events during CRT implantation. Thus, preventive strategies should be employed to minimize complication rate.

Utilization and in-hospital complications of cardiac resynchronization therapy: trends in the United States from 2003 to 2013

Aims

Cardiac resynchronization therapy (CRT) device implantation has been shown to reduce morbidity and mortality in selected patients with heart failure. We sought to investigate the utilization and in-hospital complications of cardiac resynchronization therapy defibrillator (CRT-D) and pacemaker (CRT-P) implantations in the United States from 2003 to 2013.

Methods and results

Patients receiving CRT-D or CRT-P were identified in the National Inpatient Sample database (NIS), using the International Classification of Diseases-Ninth Revision-Clinical Modification procedure codes. Annual implantation rates, patient demographics, co-morbidities, in-hospital complications, and length of stay were analysed. From 2003 to 2013, an estimated total of 439 010 (95% CI: 406 723-471 296) inpatient CRT implantations were performed in the U.S. The median age of patients was 72 and 71% were male. Overall, 6.1% had at least one complication. During the study period, comorbidity index and overall complication rate increased (P = 0.002 and P = 0.01, respectively). Mortality and length of stay showed no significant trend. Predictors of complications included: age 65 and older, female sex (OR: 1.19; 95% CI: 1.12-1.27), Deyo-Charlson Comorbidity Index, and elective admission (OR: 0.61; 95% CI: 0.57-0.66).

Conclusion

From 2003 to 2013, the severity of comorbid conditions increased and a rising trend was observed in the rate of periprocedural complications among patients undergoing CRT in the United States. In-hospital mortality and length of stay showed no uniform trend.

Effects of Cardiac Resynchronization Therapy on Ventricular Electrical Remodeling in Patients With Heart Failure

Cardiac resynchronization therapy (CRT) reverses structural remodeling of the left ventricle. We investigated whether CRT reverses left-ventricular electrical remodeling.Eighty patients were enrolled and implanted with CRT-devices. Echocardiography and electrocardiography data were obtained from each patient prior to implantation and two years after implantation. At two years after implantation, the patients were classified into a responder group and a non-responder group based on echocardiography.Over the next 2 years, 75 patients completed follow-up, and 5 patients had died. Echocardiography results showed that 23 patients could be classified as non-responders and 52 as responders. Larger numbers of non-responders were diagnosed with either ischemic cardiomyopathy (ICM) or nonspecific intraventricular conduction delay (NICD). The intrinsic QRS duration was not changed in responders, patients with dilated cardiomyopathy, or in the patient categories of male and female. However, the intrinsic QRS duration was significantly prolonged in non-responders and patients with ischemic cardiomyopathy (P = 0.041). The mean left ventricular end-diastolic diameter in the responder group was significantly decreased by CRT (P < 0.05), while there was no significant change in intrinsic QRS duration.While CRT does not reduce the intrinsic QRS duration, it can delay negative ventricular electrical remodeling. Continuous CRT is necessary.

ICD and CRT use in ischemic heart disease in women

Although the role of implantable cardioverter defibrillator (ICD) and cardiac resynchronization therapy (CRT) in improving outcomes in ischemic cardiomyopathy (ICM) has been described, the data regarding gender-based survival outcomes are limited. There is a higher preponderance of non-ischemic cardiomyopathy (NICM) in women, and most of the ICM literature is derived from sub-study analysis. This review summarizes the current body of literature on prognosis, pathophysiology, and the present clinical practice for device implantation in women with ICM.