New York Heart Association class and the survival benefit from primary prevention implantable cardioverter defibrillators: A pooled analysis of 4 randomized controlled trials

New York Heart Association functional class and implantable cardioverter-defibrillator in non-ischaemic heart failure with reduced ejection fraction: Extended follow-up of the DANISH trial

AIMS

Current guidelines recommend implantable cardioverter-defibrillator (ICD) therapy in patients with heart failure, a left ventricular ejection fraction of ≤35%, and New York Heart Association (NYHA) class II-III. However, the evidence regarding the benefit of primary prevention ICD is less consistent in patients with NYHA class III. We investigated the long-term effects of primary prevention ICD implantation according to NYHA class in an extended follow-up study of the DANISH trial.

METHODS AND RESULTS

The DANISH trial randomized 1116 patients with non-ischaemic heart failure with reduced ejection fraction (HFrEF) to ICD implantation or usual care. Outcomes were analysed according to NYHA class at baseline (NYHA class II and III/IV). The primary outcome was all-cause mortality. Of the 1116 patients randomized in the DANISH trial, 597 (53.5%) were in NYHA class II at baseline, 505 (45.3%) in NYHA class III, and 14 (1.3%) in NYHA class IV. During a median follow-up of 9.5 years, NYHA class III/IV, compared with NYHA class II, were associated with a greater long-term rate of all-cause mortality (hazard ratio [HR] 1.52, 95% confidence interval [CI] 1.20-1.93) and cardiovascular death (HR 1.95 [1.47-2.60]). ICD implantation, compared with usual care, did not reduce the long-term rate of all-cause mortality (all participants: HR 0.89 [95% CI 0.74-1.08]; NYHA class II: HR 0.85 [0.64-1.13]; NYHA class III/IV: HR 0.89 [0.69-1.14]; pinteraction = 0.78) or cardiovascular death (all participants: HR 0.87 [95% CI 0.70-1.09]; NYHA class II: HR 0.78 [0.54-1.12]; NYHA class III/IV: HR 0.89 [0.67-1.19]; pinteraction = 0.58), irrespective of NYHA class. Similarly, NYHA class did not modify the beneficial effects of ICD implantation on sudden cardiovascular death (all participants: HR 0.60 [95% CI 0.40-0.92]; NYHA class II: HR 0.73 [0.40-1.36]; NYHA class III/IV: HR 0.52 [0.29-0.94]; pinteraction = 0.39).

CONCLUSIONS

In patients with non-ischaemic HFrEF, ICD implantation, compared with usual care, did not reduce the overall mortality rate, but it did reduce sudden cardiovascular death, regardless of baseline NYHA class.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov NCT00542945.

Frailty Status Modifies the Efficacy of ICD Therapy for Primary Prevention Among Patients With HF

BACKGROUND

Implantable cardioverter-defibrillator (ICD) therapy is recommended to reduce mortality risk in patients with heart failure with reduced ejection fraction (HFrEF). Frailty is common among patients with HFrEF and is associated with increased mortality risk. Whether the therapeutic efficacy of ICD is consistent among frail and nonfrail patients with HFrEF remains unclear.

OBJECTIVES

The aim of this study was to evaluate the effect modification of baseline frailty burden on ICD efficacy for primary prevention among participants of the SCD-HeFT (Sudden Cardiac Death in Heart Failure Trial).

METHODS

Participants in SCD-HeFT with HFrEF randomized to ICD vs placebo were included. Baseline frailty was estimated using the Rockwood Frailty Index (FI), and participants were stratified into high (FI > median) vs low (FI ≤ median) frailty burden groups. Multivariable Cox models with multiplicative interaction terms (frailty × treatment arm) were constructed to evaluate whether baseline frailty status modified the treatment effect of ICD for all-cause mortality.

RESULTS

The study included 1,676 participants (mean age: 59 ± 12 years, 23% women) with a median FI of 0.30 (IQR: 0.23-0.37) in the low frailty group and 0.54 (IQR: 0.47-0.60) in the high frailty group. In adjusted Cox models, baseline frailty status significantly modified the treatment effect of ICD therapy (Pinteraction = 0.047). In separate stratified analysis by frailty status, ICD therapy was associated with a lower risk of all-cause mortality among participants with low frailty burden (HR: 0.56; 95% CI: 0.40-0.78) but not among those with high frailty burden (HR: 0.86; 95% CI: 0.68-1.09).

CONCLUSIONS

Baseline frailty modified the efficacy of ICD therapy with a significant mortality benefit observed among participants with HFrEF and a low frailty burden but not among those with a high frailty burden.

Clinical practice guidelines for diagnostic and treatment of the chronic heart failure

Chronic heart failure continues to be one of the main causes of impairment in the functioning and quality of life of people who suffer from it, as well as one of the main causes of mortality in our country and around the world. Mexico has a high prevalence of risk factors for developing heart failure, such as high blood pressure, diabetes, and obesity, which makes it essential to have an evidence-based document that provides recommendations to health professionals involved in the diagnosis and treatment of these patients. This document establishes the clinical practice guide (CPG) prepared at the initiative of the Mexican Society of Cardiology (SMC) in collaboration with the Iberic American Agency for the Development and Evaluation of Health Technologies, with the purpose of establishing recommendations based on the best available evidence and agreed upon by an interdisciplinary group of experts. This document complies with international quality standards, such as those described by the US Institute of Medicine (IOM), the National Institute of Clinical Excellence (NICE), the Intercollegiate Network for Scottish Guideline Development (SIGN) and the Guidelines International Network (G-I-N). The Guideline Development Group was integrated in a multi-collaborative and interdisciplinary manner with the support of methodologists with experience in systematic literature reviews and the development of CPG. A modified Delphi panel methodology was developed and conducted to achieve an adequate level of consensus in each of the recommendations contained in this CPG. We hope that this document contributes to better clinical decision making and becomes a reference point for clinicians who manage patients with chronic heart failure in all their clinical stages and in this way, we improve the quality of clinical care, improve their quality of life and reducing its complications.

Incidence, risk assessment and prevention of sudden cardiac death in cardiomyopathies

Cardiomyopathies are a significant contributor to cardiovascular morbidity and mortality, mainly due to the development of heart failure and increased risk of sudden cardiac death (SCD). Despite improvement in survival with contemporary treatment, SCD remains an important cause of mortality in cardiomyopathies. It occurs at a rate ranging between 0.15% and 0.7% per year (depending on the cardiomyopathy), which significantly surpasses SCD incidence in the age- and sex-matched general population. The risk of SCD is affected by multiple factors including the aetiology, genetic basis, age, sex, physical exertion, the extent of myocardial disease severity, conduction system abnormalities, and electrical instability, as measured by various metrics. Over the past decades, the knowledge on the mechanisms and risk factors for SCD has substantially improved, allowing for a better-informed risk stratification. However, unresolved issues still challenge the guidance of SCD prevention in patients with cardiomyopathies. In this review, we aim to provide an in-depth discussion of the contemporary concepts pertinent to understanding the burden, risk assessment and prevention of SCD in cardiomyopathies (dilated, non-dilated left ventricular, hypertrophic, arrhythmogenic right ventricular, and restrictive). The review first focuses on SCD incidence in cardiomyopathies and then summarizes established and emerging risk factors for life-threatening arrhythmias/SCD. Finally, it discusses validated approaches to the risk assessment and evidence-based measures for SCD prevention in cardiomyopathies, pointing to the gaps in evidence and areas of uncertainties that merit future clarification.

Implantable Cardioverter-Defibrillator for Primary Prevention in Asia

In a contemporary setting, where the risk of sudden cardiac death (SCD) is low, heart failure management is improved, and technology is advanced, identifying the patients who would benefit the most from an implantable cardioverter-defibrillator (ICD) treatment for primary prevention remains a challenge. The prevalence of SCD is lower in Asia when compared with the United States/Europe (35-45 per 100,000 person-years vs 55-100 per 100,000 person-years, respectively). Nevertheless, this should not explain the enormous gap in ICD's utilization among eligible candidates (∼12% in Asia vs ∼45% in the United States/Europe). The disparity between Asia and Western countries, together with significant variation among the Asian population and the previously mentioned challenges, requires an individualized approach and specific regional recommendation, especially in countries with limited resources where ICDs are being extremely underutilized This review focuses on the current knowledge of ICD therapy for SCD prevention and how to improve patient and device selection.

Predictors of proarrhythmic effect in heart failure patients after 9-week hybrid comprehensive telerehabilitation and their influence on cardiovascular mortality in long-term follow-up: Subanalysis of the TELEREH-HF randomized clinical trial

BACKGROUND

Regular exercise training is beneficial in heart failure (HF) patients. However, its potential proarrhythmic effect is possible but has not been sufficiently investigated.

OBJECTIVE

To identify patients at risk for proarrhythmic effect after the 9-week of hybrid comprehensive telerehabilitation (HCTR) program vs the 9-week of usual care (UC) and to investigate its predictors and impact on cardiovascular mortality based on data from the TELEREH-HF RCT.

METHODS

Proarrhythmic effect, strictly defined on the basis of available standards was evaluated by comparing 24-h Holter ECG before and after 9-week of HCTR or UC of 773 HF patients (The New York Heart Association class I-III, left ventricular ejection fraction ≤40%).

RESULTS

The proarrhytmic effect was found in 78 (20.4%) and in 61 (15.6%) patients in the HCTR and UC group respectively, and the difference between groups was not statistically significant (p = 0.081). However, univariate analysis identified several statistically significant predictors of proarrhythmia in HCTR only vs the UC group. After a multivariate analysis ischaemic aetiology of HF (OR = 2.27, p = 0.008), peak oxygen consumption at baseline <14 ml/kg/min (OR = 2.03, p = 0.012) and level of N-terminal-pro B-type natriuretic peptide (NT-proBNP) in the first and the second tercile (OR = 1.85, p = 0.043) were identified to be independent predictors of proarrhytmic effect of exercise training among the HF patients in HCTR group only.

CONSLUSIONS

Patients who underwent a 9-week HCTR were not at a higher risk of proarrhythmic effect after its completion compared to UC. However, predictors of proarrhythmia such as ischemic aetiology of HF, poor physical capacity, lower NT-proBNP level were discovered in the HCTR group only, yet it does not cause a significant risk of cardiovascular mortality including sudden cardiac death in long-term follow-up.

A Magic Bullet: Bullet Embolism From the Heart to the Femoral Artery

A case study a patient who was emergently evaluated with an intraoperative transesophageal echocardiography after suffering a gunshot wound to the back is provided. This diagnostic examination revealed a left atrium to aorta fistula, due to the path of the bullet through the body. Immediate postoperative imaging with computed tomography revealed that the bullet had embolized to the left femoral artery from which it was later surgically removed. This rare clinical phenomenon of bullet embolization, involving the heart and associated vasculature, is reviewed.

Frailty in elderly inpatients with cardiovascular disease: an exploration of associated factors

AIMS

Older patients with cardiovascular diseases (CVDs) are more likely to develop frailty. Few studies have investigated frailty status, and its multiple associated factors, in this population. The aim of the present study was to explore frailty status, and its multidimensional associated factors, in elderly inpatients with CVDs.

METHODS AND RESULTS

In this cross-sectional study, 1021 inpatients with CVDs aged ≥60 years old were recruited through convenience sampling from multiple hospitals in Suzhou, China. The FRAIL scale was used to assess frailty. A self-designed questionnaire gathered sociodemographic, clinical, and health-related information related to the physiological, psychological, and social dimensions of frailty. Among the 629 elderly inpatients with CVDs (73.64 ± 7.93 years old) who met inclusion criteria and completed the assessments, 176 (28.0%) were classified as frail. Univariate analyses demonstrated that the proportion of frailty was significantly associated with multiple factors. Logistic regression analysis indicated that, compared to their counterparts, the risk of frailty was higher in participants with cardiac function classes II, III, and IV [odds ratio (OR) = 1.866, 3.393, and 6.351, respectively]; average and bad mastication function (OR = 2.534 and 2.945, respectively); and often or always using walking aids (OR = 2.713). Conversely, the risk of frailty was lower in participants with good nutritional status (OR = 0.879) and regular exercise habits (OR = 0.573), as compared with their counterparts.

CONCLUSION

Frailty in elderly inpatients with CVDs is common and associated with multiple physiological factors including cardiac function, mastication function, nutritional status, use of walking aids, and regular exercise habits.

Cost-effectiveness of implantable cardioverter-defibrillators for primary prevention of sudden cardiac death

INTRODUCTION AND OBJECTIVES

Implantable cardioverter-defibrillators (ICD) are a cost-effective alternative for secondary prevention of sudden cardiac death, but their efficiency in primary prevention, especially among patients with nonischemic heart disease, is still uncertain.

METHODS

We performed a cost-effectiveness analysis of ICD plus conventional medical treatment (CMT) vs CMT for primary prevention of cardiac arrhythmias from the perspective of the national health service. We simulated the course of the disease by using Markov models in patients with ischemic and nonischemic heart disease. The parameters of the model were based on the results obtained from a meta-analysis of clinical trials published between 1996 and 2018 comparing ICD plus CMT vs CMT, the safety results of the DANISH trial, and analysis of real-world clinical practice in a tertiary hospital.

RESULTS

We estimated that ICD reduced the likelihood of all-cause death in patients with ischemic heart disease (HR, 0.70; 95%CI, 0.58-0.85) and in those with nonischemic heart disease (HR, 0.79; 95%CI, 0.66-0.96). The incremental cost-effectiveness ratio (ICER) estimated with probabilistic analysis was €19 171/quality adjusted life year (QALY) in patients with ischemic heart disease and €31 084/QALY in those with nonischemic dilated myocardiopathy overall and €23 230/QALY in patients younger than 68 years.

CONCLUSIONS

The efficiency of single-lead ICD systems has improved in the last decade, and these devices are cost-effective in patients with ischemic and nonischemic left ventricular dysfunction younger than 68 years, assuming willingness to pay as €25 000/QALY. For older nonischemic patients, the ICER was around €30 000/QALY.

What causes sudden death in patients with chronic heart failure and a reduced ejection fraction?

Sudden death characterizes the mode of demise in 30–50% of patients with chronic heart failure and a reduced ejection fraction. Occasionally, these events have an identifiable pathophysiological trigger, e.g. myocardial infarction, catecholamine surges, or electrolyte imbalances, but in most circumstances, there is no acute precipitating mechanism. Instead, adverse left ventricular remodelling and fibrosis creates an exceptionally fragile and highly vulnerable substrate, which can be characterized using the model developed in theoretical physics of ‘self-organizing criticality’. This framework has been applied to describe the genesis of avalanches, nodes of traffic congestion unrelated to an accident, the abrupt system-wide failure of electrical grids, and the initiation of cancer and neurodegenerative diseases. Self-organizing criticality within the ventricular myocardium relies on complex adaptations to progressive stress and stretch, which evolve inevitably to an abrupt end (termed ‘cascading failure’), even though the rate of deterioration of the underlying disease process has not changed. The result is acute circulatory collapse (i.e. sudden death) in the absence of an identifiable triggering event. Cascading failure in a severely remodelled or fibrotic heart can become manifest electrically as a first-time ventricular tachyarrhythmia that is responsive to the shock delivered by an implantable cardioverter-defibrillator (ICD). Alternatively, it may present as an acute mechanical failure, which is manifest as (i) asystole, bradyarrhythmia, or electromechanical dissociation; or (ii) incessant ventricular fibrillation that persists despite repetitive ICD discharges; in both instances, the sudden deaths cannot be prevented by an ICD. This conceptual framework explains why anti-remodelling and antifibrotic interventions (i.e. neurohormonal antagonists and cardiac resynchronization) reduce the risk of sudden death in patients with heart failure in the absence of an ICD and provide incremental benefits in those with an ICD. The adoption of anti-remodelling and antifibrotic treatments may explain why the incidence of sudden death in clinical trials of heart failure has declined dramatically over the past 10–15 years, independent of the use of ICDs.

Clinical effectiveness of primary prevention implantable cardioverter-defibrillators: results of the EU-CERT-ICD controlled multicentre cohort study

Aims

The EUropean Comparative Effectiveness Research to Assess the Use of Primary ProphylacTic Implantable Cardioverter-Defibrillators (EU-CERT-ICD), a prospective investigator-initiated, controlled cohort study, was conducted in 44 centres and 15 European countries. It aimed to assess current clinical effectiveness of primary prevention ICD therapy.

Methods and results

We recruited 2327 patients with ischaemic cardiomyopathy (ICM) or dilated cardiomyopathy (DCM) and guideline indications for prophylactic ICD implantation. Primary endpoint was all-cause mortality. Clinical characteristics, medications, resting, and 12-lead Holter electrocardiograms (ECGs) were documented at enrolment baseline. Baseline and follow-up (FU) data from 2247 patients were analysable, 1516 patients before first ICD implantation (ICD group) and 731 patients without ICD serving as controls. Multivariable models and propensity scoring for adjustment were used to compare the two groups for mortality. During mean FU of 2.4 ± 1.1 years, 342 deaths occurred (6.3%/years annualized mortality, 5.6%/years in the ICD group vs. 9.2%/years in controls), favouring ICD treatment [unadjusted hazard ratio (HR) 0.682, 95% confidence interval (CI) 0.537–0.865, P = 0.0016]. Multivariable mortality predictors included age, left ventricular ejection fraction (LVEF), New York Heart Association class <III, and chronic obstructive pulmonary disease. Adjusted mortality associated with ICD vs. control was 27% lower (HR 0.731, 95% CI 0.569–0.938, P = 0.0140). Subgroup analyses indicated no ICD benefit in diabetics (adjusted HR = 0.945, P = 0.7797, P for interaction = 0.0887) or those aged ≥75 years (adjusted HR 1.063, P = 0.8206, P for interaction = 0.0902).

Conclusion

In contemporary ICM/DCM patients (LVEF ≤35%, narrow QRS), primary prophylactic ICD treatment was associated with a 27% lower mortality after adjustment. There appear to be patients with less survival advantage, such as older patients or diabetics.

Dynamic changes in cardiovascular and systemic parameters prior to sudden cardiac death in heart failure with reduced ejection fraction: a PARADIGM-HF analysis

AIMS

Prognostic models of sudden cardiac death (SCD) typically incorporate data at only a single time-point. We investigated independent predictors of SCD addressing the impact of integrating time-varying covariates to improve prediction assessment.

METHODS AND RESULTS

We studied 8399 patients enrolled in the PARADIGM-HF trial and identified independent predictors of SCD (n = 561, 36% of total deaths) using time-updated multivariable-adjusted Cox models, classification and regression tree (CART), and logistic regression analysis. Compared with patients who were alive or died from non-sudden cardiovascular deaths, patients who suffered a SCD displayed a distinct temporal profile of New York Heart Association (NYHA) class, heart rate and levels of three biomarkers (albumin, uric acid and total bilirubin), with significant differences observed more than 1 year prior to the event (P_interaction  < 0.001). In multivariable models adjusted for baseline covariates, seven time-updated variables independently contributed to SCD risk (incremental likelihood chi-square = 46.2). CART analysis identified that baseline variables (implantable cardioverter-defibrillator use and N-terminal prohormone of B-type natriuretic peptide levels) and time-updated covariates (NYHA class, total bilirubin, and total cholesterol) improved risk stratification. CART-defined subgroup of highest risk had nearly an eightfold increment in SCD hazard (hazard ratio 7.7, 95% confidence interval 3.6-16.5; P < 0.001). Finally, changes over time in heart rate, NYHA class, blood urea nitrogen and albumin levels were associated with differential risk of sudden vs. non-sudden cardiovascular deaths (P < 0.05).

CONCLUSIONS

Beyond single time-point assessments, distinct changes in multiple cardiac-specific and systemic variables improved SCD risk prediction and were helpful in differentiating mode of death in chronic heart failure.

Association of advance care planning with place of death and utilisation of life-sustaining treatments in deceased patients at Taipei City Hospital in Taiwan

OBJECTIVE

Evidence is mixed regarding the impact of advance care planning (ACP) on place of death. This cohort study investigated the effect of ACP programmes on place of death and utilisation of life-sustaining treatments for patients during end-of-life (EOL) care.

METHODS

This prospective cohort study identified deceased patients between 2015 and 2016 at Taipei City Hospital. ACP was determined by patients' medical records and defined as a process to discuss patients' preferences with respect to EOL treatments and place of death. Place of death included hospital or home death. Stepwise logistic regression determined the association of ACP with place of death and utilisation of life-sustaining treatments during EOL care.

RESULTS

Of the 3196 deceased patients, the overall mean age was 78.6 years, and 46.5% of the subjects had an ACP communication with healthcare providers before death. During the study follow-up period, 166 individuals died at home, including 98 (6.59%) patients with ACP and 68 (3.98%) patients without ACP. After adjusting for sociodemographic factors and comorbidities, patients with ACP were more likely to die at home during EOL care (adjusted OR (AOR)=1.71, 95% CI 1.24 to 2.35). Moreover, patients with ACP were less likely to receive cardiopulmonary resuscitation (AOR 0.36, 95% CI 0.25 to 0.51) as well as intubation and mechanical ventilation support (AOR 0.54, 95% CI 0.44 to 0.67) during the last 3 months of life.

CONCLUSION

Patients with ACP were more likely to die at home and less likely to receive life-sustaining treatments during EOL care.

Early palliative care: the surprise question and the palliative care screening tool-better together

OBJECTIVE

The 'surprise question' (SQ) and the palliative care screening tool (PCST) are the common assessment tools in the early identification of patients requiring palliative care. However, the comparison of their prognostic accuracies has not been extensively studied. This study aimed to compare the prognostic accuracy of SQ and PCST in terms of recognising patients nearing end of life (EOL) and those appropriate for palliative care.

METHODS

This prospective study used both the SQ and PCST to predict patients' 12-month mortality and identified those appropriate for palliative care. All adult patients admitted to Taipei City Hospital in 2015 were included in this cohort study. The c-statistic value was calculated to indicate the predictive accuracies of the SQ and PCST.

RESULTS

Out of 21 109 patients, with a mean age of 62.8 years, 12.4% and 11.1% had a SQ response of 'no' and a PCST score of ≥4, respectively. After controlling for other covariates, an SQ response of 'no' and a PCST score of ≥4 were the independent predictors of 12-month mortality. The c-statistic values of the SQ and PCST at recognising patients in their last year of life were 0.680 and 0.689, respectively. When using a combination of both SQ and PCST in predicting patients' 12-month mortality risk, the predictive value of the c-statistic increased to 0.739 and was significantly higher than either one in isolation (p<0.001).

CONCLUSION

A combination of the SQ with PCST has better prognostic accuracy than either one in isolation.

An Interventional Study for the Early Identification of Patients With Palliative Care Needs and the Promotion of Advance Care Planning and Advance Directives

CONTEXT

Programs identifying patients needing palliative care and promoting advance care planning (ACP) are rare in Asia.

OBJECTIVES

This interventional cohort study aimed to identify hospitalized patients with palliative care needs using a validated palliative care screening tool (PCST), examine the ability of the PCST to predict mortality, and explore effects of a pragmatic ACP program targeted by PCST on the utilization of life-sustaining treatment during the last three months of life.

METHODS

In this prospective study, we used PCST to evaluate patients' palliative care needs between 2015 and 2016 and followed patients for three months. ACP with advance directives (ADs) was systematically offered to all patients with PCST score ≥4.

RESULTS

Of 47,153 hospitalized patients, 10.4% had PCST score ≥4. During follow-up, 2121 individuals died within three months of palliative care screening: 1225 (25.0%) with PCST score ≥4 and 896 (2.1%) with PCST score <4. After controlling for covariates, PCST score ≥4 was significantly associated with a higher mortality within three months of screening (adjusted odds ratio [AOR] 6.86; 95% CI 6.16-7.63). Moreover, ACP consultation (AOR 0.78; 95% CI 0.66-0.92) and AD completion (AOR 0.49; 95% CI 0.36-0.65) were associated with a lower likelihood of receiving life-sustaining treatments during the last three months of life.

CONCLUSION

We demonstrated the feasibility of implementing a comprehensive palliative care program to identify patients with palliative care needs and promote ACP and AD in Eastern Asia. ACP consultation and AD completion were associated with reduced utilization of life-sustaining treatments during the last three months of life.

Prognostic role of NYHA class in heart failure patients undergoing primary prevention ICD therapy

Aims

Concerns about the prognostic value of NYHA functional class (FC) in heart failure (HF) patients carrying a prophylactic implantable cardioverter defibrillator (ICD) are still present. We aimed to compare whether mortality and arrhythmic risk were different, in a cohort of HF patients undergoing ICD‐only implant, according to their FC.

Methods and results

HF patients with left ventricle ejection fraction (LVEF) ≤35%, undergoing first prophylactic ICD‐only implant were collected from a multicentre nationwide registry (2006–2015). Six hundred and twenty‐one patients were identified (101 patients in NYHA I; 411 in NYHA II; 109 in NYHA III). After a mean follow‐up of 4.4 years (±2.1), 126 patients died (20.3%). All‐cause mortality risk was higher in symptomatic patients: 13.9% in NYHA I patients, 18.3% in NYHA II patients (HR: 1.8, 95% CI 1.1–3.2), and 32.9% in NYHA III patients (HR: 3.9, 95% CI 2.1–7.3). Seventy‐eight out of all deaths were due to cardiovascular causes (12.6%). Cardiovascular mortality risk was also higher in symptomatic patients: 6.9% in NYHA I patients, 11% in NYHA II patients (HR: 2.2, 95% CI 1.1–4.9), and 23.9% in NYHA III (HR: 5.5, 95% CI 2.4–12.7). One hundred and seventeen patients received a first appropriate ICD therapy (19.4%). Arrhythmia free survival did not differ among study groups [20.8% in NYHA I patients, 18.7% in NYHA II (HR: 1.1, 95% CI 0.6–1.7) and 20.8% in NYHA III patients (HR: 1.3, 95% CI 0.7–2.5)]. NYHA class independently predicted cardiovascular mortality (NYHA III vs. NYHA I: HR, 4.7; 95% CI, 1.7–12.8, P = 0.002; NYHA II vs. NYHA I: HR, 2.1, 95% CI, 1.0–5.6, P = 0.05) but not all‐cause death (NYHA III vs. NYHA I: HR: 1.8, 95% CI 0.8–3.9, P = 0.11; NYHA II vs. NYHA I: HR, 1.1, 95% CI 0.6–2.2, P = 0.71;). Atrial fibrillation, chronic kidney disease, and diabetes emerged as predictors of both all‐cause death [(HR: 1.8, 95% CI 1.2–2.8, P = 0.005), (HR: 2.2, 95% CI 1.4–3.4, P < 0.001), (HR: 2.0, 95% CI 1.3–3.1, P = 0.001), respectively] and cardiovascular mortality [(HR: 1.8, 95% CI 1.1–3.1, P = 0.02), (HR: 3.1, 95% CI 1.8–5.4, P < 0.001), (HR: 1.7, 95% CI 1.1–3, P = 0.032), respectively].

Conclusions

Mortality in HF patients undergoing prophylactic ICD implantation was higher in symptomatic patients. NYHA functional class along with other comorbidities might be helpful to identify a subgroup of ICD carriers with poorer prognosis and higher risk of cardiovascular death.

The Benefit of Prophylactic Implantable Cardioverter Defibrillator Implantation in Asymptomatic Heart Failure Patients With a Reduced Ejection Fraction

Recommendations for prophylactic implantable cardioverter defibrillator (ICD) implantation in asymptomatic heart failure patients with a reduced left ventricular ejection fraction (LVEF) differ between guidelines. Evidence on the risk of appropriate device therapy (ADT) and death in New York Heart Association (NYHA) class I patients is scarce. Aim of this study is to evaluate ADT and mortality in NYHA-I primary prevention ICD patients with a LVEF ≤35%. A retrospective cohort was studied, including 572 patients with LVEF ≤35% who received a prophylactic ICD with or without resynchronization therapy (CRT-D). To evaluate the incidence of ADT and mortality, NYHA-I was compared with NYHA-II-III using Cox regression analysis. During a follow-up of 4.1 ± 2.4 years, 33% of the NYHA-I patients received ADT compared with 20% of the NYHA-II-III patients (hazard ratio 1.5, 95% confidence interval 1.04 to 2.31, p = 0.03). No differences in mortality were observed (hazard ratio 0.70, 95% confidence interval 0.49 to 1.07, p = 0.10). Additional analyses showed no difference in time to ADT excluding CRT patients (ICD-NYHA-I patients vs ICD-NYHA-II-III patients, p = 0.17) and comparing ischemic and nonischemic cardiomyopathy NYHA-I patients (p = 0.13). Multivariable Cox regression analyses showed that NYHA class was the strongest independent predictor of ADT. In conclusion, primary prevention NYHA-I ICD patients showed a higher incidence of ADT compared with NYHA-II-III ICD patients. These results strongly suggest that primary prevention NYHA-I patients with a LVEF ≤35% are likely to benefit from ICD therapy and should not be excluded from a potentially life-saving therapy.

Association of cardiovascular magnetic resonance-derived circumferential strain parameters with the risk of ventricular arrhythmia and all-cause mortality in patients with prior myocardial infarction and primary prevention implantable cardioverter defibrillator

BACKGROUND

Impaired left ventricular (LV) contraction and relaxation may further promote adverse remodeling and may increase the risk of ventricular arrhythmia (VA) in ischemic cardiomyopathy. We aimed to examine the association of cardiovascular magnetic resonance (CMR)-derived circumferential strain parameters for LV regional systolic function, LV diastolic function and mechanical dispersion with the risk of VA in patients with prior myocardial infarction and primary prevention implantable cardioverter defibrillator (ICD).

METHODS

Patients with an ischemic cardiomyopathy who underwent CMR prior to primary prevention ICD implantation, were retrospectively identified. LV segmental circumferential strain curves were extracted from short-axis cine CMR. For LV regional strain analysis, the extent of moderately and severely impaired strain (percentage of LV segments with strain between - 10% and - 5% and > - 5%, respectively) were calculated. LV diastolic function was quantified by the early and late diastolic strain rate. Mechanical dispersion was defined as the standard deviation in delay time between each strain curve and the patient-specific reference curve. Cox proportional hazard ratios (HR) (95%CI) were calculated to assess the association between LV strain parameters and appropriate ICD therapy.

RESULTS

A total of 121 patients (63 ± 11 years, 84% men, LV ejection fraction (LVEF) 27 ± 9%) were included. During a median (interquartile range) follow-up of 47 (27;69) months, 30 (25%) patients received appropriate ICD therapy. The late diastolic strain rate (HR 1.1 (1.0;1.2) per - 0.25 1/s, P = 0.043) and the extent of moderately impaired strain (HR 1.5 (1.0;2.2) per + 10%, P = 0.048) but not the extent of severely impaired strain (HR 0.9 (0.6;1.4) per + 10%, P = 0.685) were associated with appropriate ICD therapy, independent of LVEF, late gadolinium enhancement (LGE) scar border size and acute revascularization. Mechanical dispersion was not related to appropriate ICD therapy (HR 1.1 (0.8;1.6) per + 25 ms, P = 0.464).

CONCLUSIONS

In an ischemic cardiomyopathy population referred for primary prevention ICD implantation, the extent of moderately impaired strain and late diastolic strain rate were associated with the risk of appropriate ICD therapy, independent of LVEF, scar border size and acute revascularization. These findings suggest that disturbed LV contraction and relaxation may contribute to an increased risk of VA after myocardial infarction.

Who Benefits From a Defibrillator-Balancing the Risk of Sudden Versus Non-sudden Death

PURPOSE OF REVIEW

Treatment with a defibrillator can reduce the risk of sudden death by terminating ventricular arrhythmias. The identification of patient groups in whom this function reduces overall mortality is challenging. In this review, we summarise the evidence for who benefits from a defibrillator.

RECENT FINDINGS

Recent evidence suggests that contemporary pharmacologic and non-defibrillator device therapies are altering the potential risks and benefits of a defibrillator. Who benefits from a defibrillator is determined by both the risk of sudden death and the competing risk of other, non-sudden causes of death. The balance of these risks is changing, which calls into question whether historic evidence for the use of defibrillators remains robust in the modern era.

Meta-Analysis of Risk of Ventricular Arrhythmias and All-Cause Mortality in Patients With Chronic Total Occlusion of a Coronary Artery and/or Implantable Cardioverter-Defibrillator

Implantable cardioverter-defibrillator (ICD) has been increasingly used to prevent sudden death in patients with high risk of ventricular arrhythmias (VAs). Chronic total occlusion (CTO) is a severe condition of coronary artery disease. However, the prognostic impact of CTO in ICD recipients remains controversial. We systematically searched the PubMed, EMBASE, and Cochrane databases for documents published before October 1, 2017 to identify studies that investigated the prognostic impact of CTO on VAs and all-cause mortality (ACM) in ICD recipients. The effect size was expressed by hazard ratio (HR) and 95% confidence interval (CI). Overall, 6 studies with 1,423 patients were included. We found that CTO independently predicted the occurrence of VAs in the global population (HR 1.77, 95% CI 1.14 to 2.76, p = 0.01). Subgroup analysis revealed that CTO only predicted VAs in patients receiving ICD as secondary prevention (HR 1.96, 95% CI 1.55 to 2.48, p <0.01). However, CTO was not associated with ACM in the global population (HR 1.51, 95% CI 0.99 to 2.32, p = 0.06). Further subgroup analysis still showed no association between CTO and ACM in patients receiving ICD as primary prevention (HR 1.49, 95% CI 0.43 to 5.21, p = 0.53) or secondary prevention (HR 1.56, 95% CI 0.87 to 2.78, p = 0.13). In conclusion, CTO is an independent predictor of VAs in patients with secondary-prevention ICD, but not for ACM. Our study provided additional evidence for improving the risk stratification and management of VAs in ICD recipients.

The subcutaneous implantable cardioverter defibrillator--review of the recent data

The subcutaneous implantable cardioverter defibrillators (SICD) is an alternative to the transvenous ICD for the prevention of sudden cardiac death (SCD). Multiple studies have shown that the SICD is safe and effective in treating ventricular arrhythmias. While earlier studies mainly enrolled younger patients with channelopathies, more recent reports included patients with “typical” indications for ICD therapy for the prevention of SCD. In this review we summarize the data available to date on the SICD while highlighting its pros and cons.