Comparison of Multivariate Risk Estimation Models to Predict Prognosis in Patients With Implantable Cardioverter Defibrillators With or Without Cardiac Resynchronization Therapy

Prophylactic ICD Survival Benefit Prediction: Review and Comparison between Main Scores

Current guidelines advocate for the use of prophylactic implantable cardioverter defibrillators (ICDs) for all patients with symptomatic heart failure (HF) with low ejection fraction (EF). As many patients will never use their device and some are prone to device-related complications, scoring systems for delineating subgroups with differential ICD survival benefits are crucial to maximize ICD benefit and mitigate complications. This review summarizes the main scores, including MADIT trial-based Risk Stratification Score (MRSS) and Seattle Heart Failure Model (SHFM), which are based on randomized trials with a control group (HF medication only) and validated on large cohorts of 'real-world' HF patients. Recent studies using cardiac MRI (CMR) to predict ventricular arrhythmia (VA) are mentioned as well. The review shows that most scores could not delineate sustained VA incidence, but rather mortality without prior appropriate ICD therapies. Multiple scores could identify high-risk subgroups with extremely high probability of early mortality after ICD implant. On the other hand, low-risk subgroups were defined, in whom a high ratio of appropriate ICD therapy versus death without prior appropriate ICD therapy was found, suggesting significant ICD survival benefit. Moreover, MRSS and SHFM proved actual ICD survival benefit in low- and medium-risk subgroups when compared with control patients, and no benefit in high-risk subgroups, consisting of 16-20% of all ICD candidates. CMR reliably identified areas of myocardial scar and 'channels', significantly associated with VA. We conclude that as for today, multiple scoring models could delineate patient subgroups that would benefit differently from prophylactic ICD. Due to their modest-moderate predictability, these scores are still not ready to be implemented into clinical guidelines, but could aid decision regarding prophylactic ICD in borderline cases, as elderly patients and those with multiple co-morbidities. CMR is a promising technique which might help delineate patients with a low- versus high-risk for future VA, beyond EF alone. Lastly, genetic analysis could identify specific mutations in a non-negligible percent of patients, and a few of these mutations were found to predict an increased arrhythmic risk.

Comparison of mortality prediction scores in elderly patients with ICD for heart failure with reduced ejection fraction

BACKGROUND

This investigation aimed to examine and compare the predictive value of MADIT-II, FADES, PACE and SHOCKED scores in predicting one-year and long-term all-cause mortality in implantable cardioverter-defibrillator (ICD) implanted patients, 75 years old and older, since there has been an area of uncertainty about the utility and usefulness of these available risk scores in such cases.

METHODS

In this observational, retrospective study, 189 ICD implanted geriatric patients were divided into two groups according to the presence of long-term mortality in follow-up. The baseline characteristics and laboratory variables were compared between the groups. MADIT-II, FADES, PACE and SHOCKED scores were calculated at the time of ICD implantation. One-year and long-term predictive values of these scores were compared by a receiver-operating curve (ROC) analysis.

RESULTS

A ROC analysis showed that the best cutoff value of the MADIT-II score to predict one-year mortality was ≥ 3 with 87% sensitivity and 74% specificity (AUC 0.83; 95% CI 0.73-0.94; p < 0.001) and that for long-term mortality was ≥ 2 with 83% sensitivity and 43% specificity (AUC 0.68; 95% CI 0.60-0.76; p < 0.001). The predictive value of MADIT-II was superior to FADES, PACE and SHOCKED scores in ICD implanted patients who are 75 years and older.

CONCLUSION

MADIT-II score has a significant prognostic value as compared to FADES, PACE and SHOCKED scores for the prediction of one-year and long-term follow-up in geriatric patients with implanted ICDs for heart failure with reduced ejection fraction.

Predicting Early Mortality Among Implantable Defibrillator Patients Treated With Cardiac Resynchronization Therapy

BACKGROUND

The beneficial effects of a cardiac resynchronization defibrillator (CRT-D) in patients with heart failure, low left ventricular ejection fraction (LVEF), and wide QRS have clearly been established. Nevertheless, mortality remains high in some patients. The aim of this study was to develop and validate a risk score to identify patients at high risk for early mortality who are implanted with a CRT-D.

METHODS AND RESULTS

For predictive modelling, 1282 consecutive patients from 5 centers (74% male; median age 66 years; median LVEF 25%; New York Heart Association class III-IV 60%; median QRS-width 160 ms) were randomly divided into a derivation and validation cohort. The primary endpoint is mortality at 3 years. Model development was performed using multivariate logistic regression by checking log likelihood, Akaike information criterion, and Bayesian information criterion. Model performance was validated using C statistics and calibration plots. The risk score included 7 independent mortality predictors, including myocardial infarction, LVEF, QRS duration, chronic obstructive pulmonary disease, chronic kidney disease, hyponatremia, and anemia. Calibration-in-the-large was suboptimal, reflected by a lower observed mortality (44%) than predicted (50%). The validated C statistic was 0.71 indicating modest performance.

CONCLUSION

A risk score based on routine, readily available clinical variables can assist in identifying patients at high risk for early mortality within 3 years after CRT-D implantation.

Implantable cardiac defibrillators for people with non-ischaemic cardiomyopathy

BACKGROUND

There is evidence that implantable cardioverter-defibrillator (ICD) for primary prevention in people with an ischaemic cardiomyopathy improves survival rate. The evidence supporting this intervention in people with non-ischaemic cardiomyopathy is not as definitive, with the recently published DANISH trial finding no improvement in survival rate. A systematic review of all eligible studies was needed to evaluate the benefits and harms of using ICDs for primary prevention in people with non-ischaemic cardiomyopathy.

OBJECTIVES

To evaluate the benefits and harms of using compared to not using ICD for primary prevention in people with non-ischaemic cardiomyopathy receiving optimal medical therapy.

SEARCH METHODS

We searched CENTRAL, MEDLINE, Embase, and the Web of Science Core Collection on 10 October 2018. For ongoing or unpublished clinical trials, we searched the US National Institutes of Health Ongoing Trials Register ClinicalTrials.gov, the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP), and the ISRCTN registry. To identify economic evaluation studies, we conducted a separate search to 31 March 2015 of the NHS Economic Evaluation Database, and from March 2015 to October 2018 on MEDLINE and Embase.

SELECTION CRITERIA

We included randomised controlled trials involving adults with chronic non-ischaemic cardiomyopathy due to a left ventricular systolic dysfunction with an ejection fraction of 35% or less (New York Heart Association (NYHA) type I-IV). Participants in the intervention arm should have received ICD in addition to optimal medical therapy, while those in the control arm received optimal medical therapy alone. We included studies with cardiac resynchronisation therapy when it was appropriately balanced in the experimental and control groups.

DATA COLLECTION AND ANALYSIS

The primary outcomes were all-cause mortality, cardiovascular mortality, sudden cardiac death, and adverse events associated with the intervention. The secondary outcomes were non-cardiovascular death, health-related quality of life, hospitalisation for heart failure, first ICD-related hospitalisation, and cost. We abstracted the log (hazard ratio) and its variance from trial reports for time-to-event survival data. We extracted the raw data necessary to calculate the risk ratio. We summarised data on quality of life and cost-effectiveness narratively. We assessed the certainty of evidence for all outcomes using GRADE.

MAIN RESULTS

We identified six eligible randomised trials with a total of 3128 participants. The use of ICD plus optimal medical therapy versus optimal medical therapy alone decreases the risk of all-cause mortality (hazard ratio (HR) 0.78, 95% confidence interval (CI) 0.66 to 0.92; participants = 3128; studies = 6; high-certainty evidence). An average of 24 patients need to be treated with ICD to prevent one additional death from any cause (number needed to treat for an additional beneficial outcome (NNTB) = 24). Individuals younger than 65 derive more benefit than individuals older than 65 (HR 0.51, 95% CI 0.29 to 0.91; participants = 348; studies = 1) (NNTB = 10). When added to medical therapy, ICDs probably decrease cardiovascular mortality compared to not adding them (risk ratio (RR) 0.75, 95% CI 0.46 to 1.21; participants = 1781; studies = 4; moderate-certainty evidence) (possibility of both plausible benefit and no effect). Implantable cardioverter-defibrillator was also found to decrease sudden cardiac deaths (HR 0.45, 95% CI 0.29 to 0.70; participants = 1677; studies = 3; high-certainty evidence). An average of 25 patients need to be treated with an ICD to prevent one additional sudden cardiac death (NNTB = 25). We found that ICDs probably increase adverse events (possibility of both plausible harm and benefit), but likely have little or no effect on non-cardiovascular mortality (RR 1.17, 95% CI 0.81 to 1.68; participants = 1781; studies = 4; moderate-certainty evidence) (possibility of both plausible benefit and no effect). Finally, using ICD therapy probably has little or no effect on quality of life, however shocks from the device cause a deterioration in quality of life. No study reported the outcome of first ICD-related hospitalisations.

AUTHORS' CONCLUSIONS

The use of ICD in addition to medical therapy in people with non-ischaemic cardiomyopathy decreases all-cause mortality and sudden cardiac deaths and probably decreases mortality from cardiovascular causes compared to medical therapy alone. Their use probably increases the risk for adverse events. However, these devices come at a high cost, and shocks from ICDs cause a deterioration in quality of life.

Cardiac Palliative Medicine

PURPOSE OF REVIEW

Heart failure is an illness with high morbidity and mortality that affects 5.7 million Americans. As advanced heart therapies become more prevalent care for patients and families is becoming more complex. The American Heart Association has released a policy statement recommending continuous, high-quality access to palliative care for all patients with heart failure, and the Center for Medicare Services requires palliative care involvement in mechanical circulatory support teams.

RECENT FINDINGS

The National Quality Forum developed eight domains of palliative care that are required for high-quality delivery of comprehensive palliative care. This article assesses each domain and how it pertains to evolving care of patients with advanced heart failure. Leadership from heart failure teams should review the domains of palliative care to ensure they are improving primary palliative care skills as well as identifying areas needed to improve funding so that patients have access to comprehensive specialty level palliative care.

Impact of an Age-Adjusted Co-morbidity Index on Survival of Patients With Heart Failure Implanted With Cardiac Resynchronization Therapy Devices

Age is an adverse prognostic factor in patients with heart failure. We aimed to assess the impact of age and noncardiac co-morbidities in the outcome of patients undergoing cardiac resynchronization therapy (CRT), and determine which of these two factors is the most important predictor of survival. The study involved a single-center retrospective assessment of 697 consecutive CRT implants during a 12-year period. Patient co-morbidity profile was assessed using the Charlson Co-morbidity Index (CCI) and the Charlson Age-Co-morbidity Index (CACI). Predictors of survival free from heart transplantation were assessed. CRT-related complications and cause of death analysis were assessed within tertiles of the CACI. During a mean follow-up of 1,813 ± 1,177 days, 347 patients (49.9%) died and 37 (5.3%) underwent heart transplantation. On multivariate Cox regression, female gender (HR = 0.78, 95% confidence interval [CI] 0.62 to 0.99, p = 0.041), estimated glomerular filtration rate (HR per ml/min = 0.99, 95% CI 0.98 to 0.99, p < 0.001), left ventricular ejection fraction (HR per % = 0.99, 95% CI 0.98 to 1.00, p = 0.022), New York Heart Association class (HR = 1.83, 95% CI 1.53 to 2.20, p < 0.001), presence of left bundle branch block (HR = 0.70, 95% CI 0.56 to 0.87, p = 0.001), and CACI tertile (HR = 1.37, 95% CI 1.18 to 1.59, p < 0.001) were independent predictors of all-cause mortality or heart transplantation. Compared with age and the CCI, the CACI was the best discriminator of all-cause mortality. Inappropriate therapies occurred less frequently in higher co-morbidity tertiles. In conclusion, patient co-morbidity profile adjusted to age impacts on mortality after CRT implantation. Use of the CACI may help refine guideline criteria to identify patients more likely to benefit from CRT.