Seattle Proportional Risk Model Research Articles

Sudden Cardiac Death in Heart Failure: A 20-Year Perspective From a Mediterranean Cohort

BackgroundThe prediction of sudden cardiac death (SCD) in heart failure (HF) remains an unmet need. The aim of our study was to assess the prevalence of SCD over 20 years in outpatients with HF managed in a Mediterranean multidisciplinary HF Clinic, and to compare the proportion of SCD (SCD/all-cause death) to the expected proportional occurrence based on the validated Seattle Proportional Risk Model (SPRM) score. Methods and ResultsThis prospective observational registry study included 2772 outpatients with HF admitted between August 2001 and May 2021. Patients were included when the cause of death was known and SPRM score was available. Over the 20-year study period, 1351 patients (48.7%) died during a median follow-up period of 3.8 years (interquartile range 1.6–7.6). Among these patients, the proportion of SCD out of the total of deaths was 13.6%, whereas the predicted by SPRM was 39.6%. This lower proportion of SCD was observed independently of left ventricular ejection fraction, ischemic etiology, and the presence of an implantable cardiac defibrillator. ConclusionsIn a Mediterranean cohort of outpatients with HF, the proportion of SCD was lower than expected based on the SPRM score. Future studies should investigate to what extend epidemiological and guideline-directed medical therapy patterns influence SCD.

Abstract 11960: Right Ventricular Diameter in Risk Stratification of Sudden Cardiac Death

Introduction: Right ventricular (RV) abnormalities have been linked with the risk of sudden cardiac death (SCD) in general population. This study was designed to evaluate the additional value of right ventricular diameter (RVD) in predicting life-threatening ventricular tachycardia (VT)/ventricular fibrillation (VF) in patients with implantable cardioverter-defibrillators (ICD). Hypothesis: We hypothesized that higher value of RVD would be an easily accessible predictor in decision-making of ICD implantation. Methods and Results: We enrolled 954 chronic heart failure patients, with quantitative measurements of echocardiograms obtained before ICD implantation, and then divided them according to the median level of RVD. Fine-Gray subdistribution and Cox proportional hazard regression analyses were performed to estimate the predictive value of RVD in sustained VT/VF vs. non-arrhythmic mortality (defined as death without prior sustained VT/VF), respectively. Patients with higher median level of RVD had a significantly higher incidence of VT/VF (32.9% versus 26.7%; P=0.041) over the median follow-up of 2.83 years (interquartile range: 1.33-5.27 years). After adjustment for multiple clinically relevant variables, high RVD levels were significantly associated with an increased risk of VT/VF (per 1 SD increase, hazard ratio=1.16; 95% CI, 1.05-1.27; P=0.003), but not non-arrhythmic mortality (per 1 SD increase, hazard ratio=0.97; 95% CI, 0.82-1.14; P=0.680). When adding RVD to the Seattle Proportional Risk Model (SPRM) and the MADIT-ICD VT/VF risk score, the combined models yielded significant improvement in discrimination for VT/VF. Elevated RVD also contributed to residual risk beyond left ventricular parameters including left ventricular end-diastolic diameter (LVEDD) and left ventricular ejection fraction (LVEF). The restricted mean survival time measure indicated that life gained with ICD implantation in RVD higher group were 11.0, 28.4 and 29.1 days more than their lower counterparts in one, two, and three years’ time. Conclusions: RVD is associated with a significantly increased risk of sustained VT/VF in chronic heart failure patients, and provides greater prognostic power when combined with current risk assessment tools.

Sudden cardiac death in heart failure. A 20 years perspective from a Mediterranean cohort

Abstract Background Although sudden cardiac death (SCD) has progressively decreased in the last decade, it remains an important cause of death in patients with heart failure (HF). Differences based on clinical management and regional characteristics might be important. Purpose To assess the prevalence of SCD along 20 years of study in HF outpatients of different aetiologies managed in a multidisciplinary HF Clinic, and compare this prevalence with the expected proportional occurrence according to the acknowledged Seattle Proportional Risk Model (SPRM) score. Methods In a prospective observational registry of real-life HF outpatients, modes of death were classified as SCD (any unexpected death, witnessed or not, of a previously stable patient with no evidence of worsening HF or any other known cause of death) and non-SCD (progression of HF, acute myocardial infarction, stroke, procedural, other cardiovascular causes and non-cardiovascular). Results From August 2001 to May 2021, 2772 outpatients with known cause of death and with SPRM score available were included. Out of them, 1351 (48.7%) died during a median follow-up of 3.8 years [IQR 1.6–7.8], up to 20 years. Observed prevalence of SCD in the 1351 dead patients was 13.6% while predicted SPRM prevalence was 39.6%. Annual SPRM predicted SCD mortality rate was 3.0% while observed SCD annual mortality rate was 1.3%. Figure 1 depicts cumulative incidence of causes of death through the study period. A lower prevalence of SCD was observed in every quintile of SPRM risk (Figure 2). This lower prevalence of SCD was observed independently of left ventricular ejection fraction group, ischemic or non-ischaemic aetiology and implantable cardiac defibrillator (ICD). Although the baseline SPRM predicted risk of SCD showed a significant decreasing trend (p=0.005) along the periods of admission at the Unit, the lower observed prevalence of SCD was seen in all periods of admission. Conclusions The prevalence of SCD through a perspective of 20 years in a Mediterranean HF outpatient cohort managed in a multidisciplinary HF Clinic was significantly lower than that expected according to the SPRM independently of degree of predicted risk, ischaemic aetiology, period of admission and implanted ICD. Regional lifestyle and dietary habits may have an impact on the lower rate of SCD in this Mediterranean cohort, and deserve further in-depth analyses. Funding Acknowledgement Type of funding sources: None.

Abstract 11665: Does the Benefit of Secondary Prevention Implantable Cardioverter-Defibrillators Vary Based on the Estimated Proportional Risk of Sudden Death?

Introduction: The Seattle Proportional Risk Model (SPRM) is a validated model developed in systolic heart failure patients without implantable cardioverter-defibrillators (ICDs) to estimate the proportion of all-cause mortality (ACM) due to sudden death. This study aims to ascertain if SPRM has utility in risk stratification for secondary prevention ICD. Methods: The AVID (Antiarrhythmics Versus Implantable Defibrillators) trial was a multicenter, randomized clinical trial in which 1,016 patients presenting with ventricular fibrillation or sustained, symptomatic ventricular tachycardia were randomized to ICD or antiarrhythmic (AA) drug therapy. Using routine clinical variables, we applied the SPRM to patient-level data (n=995 with complete data) and assessed if the ICD benefit for ACM varied with SPRM-predicted probability of sudden death. Results: SPRM was predictive of sudden death vs. non-sudden death in patients without an ICD (logistic regression p=0.005). The ICD hazard ratio for ACM was 0.59. ICD survival benefit varied with SPRM for ACM (p=0.013) with benefit (ICD HR≤0.80) seen in patients with SPRM>40%. ICD benefit trended higher in patients with a history of heart failure (HF) vs no HF (HR=0.52 vs. 0.81, interaction p=0.13) (Figure 1). In comparison to the AA group, patients with either HF or SPRM>51% (median) had a meaningful ICD benefit (HR=0.60, p=0.017), and patients with both HF and SPRM>51% had the greatest ICD benefit (HR=0.38, p<0.001). There was no ICD benefit if no HF and SPRM<51% (HR=1.17). Conclusions: In a population of patients with VF or sustained VT, secondary prevention ICDs decreased ACM by 41%. ICD survival benefit varied with SPRM-predicted proportion of sudden death, and trended higher in patients with HF. SPRM may therefore provide a useful tool for risk stratifying patients for secondary prevention ICD. Figure 1: Survival benefit for ICD therapy varies with SPRM-estimated proportion of sudden death, and HF versus no HF.

Sudden cardiac death after acute decompensation in heart failure patients: implications of discharge haemoglobin levels.

AimsHeart failure (HF) patients have a high risk of mortality due to sudden cardiac death (SCD) and non‐SCD, including pump failure death (PFD). Anaemia predicts more severe symptomatic burden and higher morbidity, as noted by markedly increased hospitalizations and readmission rates, and mortality, underscoring its importance in HF management. Herein, we aimed to determine whether haemoglobin (Hb) level at discharge affects the mode of death and influences SCD risk prediction.MethodsWe evaluated the data of 3020 consecutive acute HF patients from a Japanese prospective multicentre registry. Patients were divided into four groups based on discharge Hb levels. SCD was defined as an unexpected and otherwise unexplained death in a previously stable patient or death due to documented or presumed cardiac arrhythmia without a clear non‐cardiovascular cause. The mode of death (SCD, PFD or other cause) was adjudicated by a central committee. Finally, we investigated whether adding Hb level to the Seattle Proportional Risk Model (SPRM; established risk score utilized to estimate ‘proportion’ of SCD among death events) would affect its performance.ResultsThe mean age of studied patients was 74.3 ± 12.9 years, and 59.8% were male. The mean Hb level was 12.0 ± 2.1 g/dL (61.3% of patients had anaemia defined by World Health Organization criteria). During the 2‐year follow‐up, 474 deaths (15.7%) occurred, including 93 SCDs (3.1%), 171 PFDs (5.7%) and 210 other deaths (7.0%; predominantly non‐cardiac death). Absolute risk of PFD (P < 0.001) or other death (P < 0.001) increased along with the severity of anaemia, whereas the incidence of SCD was low but remained consistent across all four groups (P = 0.440). As a proportion of total deaths in each Hb level group, the contributions from non‐SCD increased and from SCD decreased along with anaemia severity (P = 0.007). Adding Hb level to the SPRM improved the overall discrimination (c‐index: 0.62 [95% confidence interval (CI) 0.56–0.69] to 0.65 [95% CI 0.59–0.71]), regardless of the baseline ejection fraction (EF) (c‐index: 0.64 [95% CI 0.55–0.73] to 0.67 [95% CI 0.58–0.75] for reduced EF and 0.55 [95% CI 0.45–0.66] to 0.61 [95% CI 0.52–0.70] for preserved EF).ConclusionsThe discharge Hb level provides information about both absolute and proportional risks for each mode of death in acute HF patients, and the addition of Hb level improves the performance of SPRM by identifying more non‐SCD cases. Future ‘proportional’ SCD risk models should incorporate Hb level as a covariate to meet this high performance.

AnaLysIs of Both sex and device specific factoRs on outcomes in pAtients with non-ischemic cardiomyopathy (BIO-LIBRA): Design and clinical protocol.

BackgroundOutcomes of patients with nonischemic cardiomyopathy and low ejection fraction implanted with an implantable cardioverter-defibrillator (ICD) or cardiac resynchronization therapy with a defibrillator (CRT-D), especially in contemporary, real-life cohorts, are not fully understood.ObjectiveWe aimed to better characterize outcomes of death and ventricular tachyarrhythmias in patients with nonischemic cardiomyopathy, implanted with an ICD or CRT-D, and specifically assess differences by sex.MethodsThe AnaLysIs of Both Sex and Device Specific FactoRs on Outcomes in PAtients with Non-Ischemic Cardiomyopathy (BIO-LIBRA) study was designed to prospectively assess outcomes of device-treated ventricular tachyarrhythmias and all-cause mortality events in nonischemic cardiomyopathy patients, indicated for an ICD or CRT-D implantation for the primary prevention of sudden cardiac death (SCD), with a specific focus on sex differences. We will enroll a total of 1000 subjects across 50 U.S. sites and follow patients for up to 3 years.ResultsThe primary objective of BIO-LIBRA is to evaluate the combined risk of all-cause mortality and treated ventricular tachycardia (VT) or ventricular fibrillation (VF) events by subject sex and by implanted device type. We will also assess all-cause mortality, VT or VF alone, cardiac death, and SCD in the total cohort, as well as by subject sex and by the implanted device type. In addition, the previously validated Seattle Proportional Risk Model (SPRM) will be used to compare the SPRM predicted incidence of SCD to the observed incidence.ConclusionsThe BIO-LIBRA study will provide novel and contemporary information regarding outcomes in patients with a NICM who receive a defibrillator.

Prediction of sudden cardiac death in Japanese heart failure patients: international validation of the Seattle Proportional Risk Model.

Heart failure (HF) is associated with an increased risk of sudden cardiac death (SCD). This study sought to demonstrate the incidence of SCD within a multicentre Japanese registry of HF patients hospitalized for acute decompensation, and externally validate the Seattle Proportional Risk Model (SPRM). We consecutively registered 2240 acute HF patients from academic institutions in Tokyo, Japan. The discrimination and calibration of the SPRM were assessed by the c-statistic, Hosmer-Lemeshow statistic, and visual plotting among non-survivors. Patient-level SPRM predictions and implantable cardioverter-defibrillator (ICD) benefit [ICD estimated hazard ratio (HR), derived from the Cox proportional hazards model in the Sudden Cardiac Death in Heart Failure Trial (SCD-HeFT)] was calculated. During the 2-year follow-up, 356 deaths (15.9%) occurred, which included 76 adjudicated SCDs (3.4%) and 280 non-SCDs (12.5%). The SPRM showed acceptable discrimination [c-index = 0.63; 95% confidence interval (CI) 0.56-0.70], similar to that of original SPRM-derivation cohort. The calibration plot showed reasonable conformance. Among HF patients with reduced ejection fraction (EF; < 40%), SPRM showed improved discrimination compared with the ICD eligibility criteria (e.g. New York Heart Association functional Class II-III with EF ≤ 35%): c-index = 0.53 (95% CI 0.42-0.63) vs. 0.65 (95% CI 0.55-0.75) for SPRM. Finally, in the subgroup of 246 patients with both EF ≤ 35% and SPRM-predicted risk of ≥ 42.0% (SCD-HeFT defined ICD benefit threshold), mean ICD estimated HR was 0.70 (30% reduction of all-cause mortality by ICD). The cumulative incidence of SCD was 3.4% in Japanese HF registry. The SPRM performed reasonably well in Japanese patients and may aid in improving SCD prediction.

Modeling defibrillation benefit for survival among cardiac resynchronization therapy defibrillator recipients

Patients with heart failure having a low expected probability of arrhythmic death may not benefit from implantable cardioverter defibrillators (ICDs). The objective was to validate models to identify cardiac resynchronization therapy (CRT) candidates who may not require CRT devices with ICD functionality. Heart failure (HF) patients with CRT-Ds and non-CRT ICDs from the National Cardiovascular Data Registry and others with no device from 3 separate registries and 3 heart failure trials were analyzed using multivariable Cox proportional hazards regression for survival with the Seattle Heart Failure Model (SHFM; estimates overall mortality) and the Seattle Proportional Risk Model (SPRM; estimates proportional risk of arrhythmic death). Among 60,185 patients (age 68.6 ± 11.3 years, 31.9% female) meeting CRT-D criteria, 38,348 had CRT-Ds, 11,389 had non-CRT ICDs, and 10,448 had no device. CRT-D patients had a prominent adjusted survival benefit (HR 0.52, 95% CI 0.50-0.55, P < .0001 versus no device). CRT-D patients with SHFM-predicted 4-year survival ≥81% (median) and a low SPRM-predicted probability of an arrhythmic mode of death ≤42% (median) had an absolute adjusted risk reduction attributable to ICD functionality of just 0.95%/year with the majority of survival benefit (70%) attributable to CRT pacing. In contrast, CRT-D patients with SHFM-predicted survival <median or SPRM >median had substantially more ICD-attributable benefit (absolute risk reduction of 2.6%/year combined; P < .0001). The SPRM and SHFM identified a quarter of real-world, primary prevention CRT-D patients with minimal benefit from ICD functionality. Further studies to evaluate CRT pacemakers in these low-risk CRT candidates are indicated.

Risk Models for Prediction of Implantable Cardioverter-Defibrillator Benefit: Insights From the DANISH Trial

ObjectivesThis study aims to identify patients with nonischemic heart failure who are more likely to benefit from implantable cardioverter-defibrillator (ICD) implantation by use of established risk prediction models. BackgroundIt has been debated whether an ICD for primary prevention reduces mortality in patients with nonischemic heart failure. MethodsThe Seattle Heart Failure Model (SHFM) predicts all-cause mortality whereas the Seattle Proportional Risk Model (SPRM) predicts the proportion of sudden cardiac death (SCD) versus nonsudden death, with a higher score indicating a greater proportion of SCD. We report the effect of ICD implantation on all-cause mortality and SCD, according to median SPRM and SHFM scores in all 1,116 patients enrolled in the DANISH (Danish study to Assess the Efficacy of ICDs in Patients with Non-ischemic Systolic Heart Failure on mortality) trial. ResultsAmong patients with an SPRM score above the median (n = 558), ICD implantation reduced all-cause mortality (hazard ratio [HR]: 0.63; 95% confidence interval [CI]: 0.43 to 0.94), whereas patients with lower SPRM scores (n = 558) had no effect (HR: 1.08; 95% CI: 0.78 to 1.49, p for interaction = 0.04). The corresponding numbers for SHFM score above and below the median were HR: 0.84; 95% CI: 0.62 to 1.13 and HR: 0.82; 95% CI: 0.53 to 1.28, respectively (p for interaction = 0.980). In 177 patients with upper SPRM/upper SHFM, ICD implantation reduced all-cause mortality (HR: 0.45; 95% CI: 0.25 to 0.80) when compared to 381 patients with lower SPRM/upper SHFM (HR: 1.09; 95% CI: 0.76 to 1.55) (p for interaction <0.001). ConclusionsNonischemic heart failure patients with high predicted relative likelihood of SCD, as estimated by higher SPRM score, seemed to benefit from ICD implantation. (DANISH [Danish ICD Study in Patients With Ditaled Cardiomyopathy]; NCT00542945)

P5667Predicting sudden cardiac death in Japanese heart failure patients: International validation of the Seattle Proportional Risk Model

P5667Predicting sudden cardiac death in Japanese heart failure patients: International validation of the Seattle Proportional Risk Model

Improving the Use of Primary Prevention Implantable Cardioverter-Defibrillators Therapy With Validated Patient-Centric Risk Estimates.

The authors previously developed the Seattle Proportional Risk Model (SPRM) in systolic heart failure patients without implantable cardioverter-defibrillators (ICDs)to predict the proportion of deaths that were sudden. They subsequently validated the SPRM in 2 observational ICD data sets. The objectives in the present study were to determine whether this validated model could improve identification of clinically important variations in the expected magnitude of ICD survival benefit by using a pivotal randomized trial of primary prevention ICD therapy. Recent data show that<50% of nominally eligible subjects receive guideline- recommended primary prevention ICDs. In the SCD-HeFT (Sudden Cardiac Death in Heart Failure Trial), a placebo-controlled ICD trial in 2,521 patients with an ejection fraction≤35% and symptomatic heart failure, we tested the use of patient-level SPRM-predicted probability of sudden death (relative to that of non-sudden death) as a summary measurement of the potential for ICD benefit. A Cox proportional hazards model was used to estimate variations in the relationship between patient-level SPRM predictions and ICD benefit. Relative to use of mortality predictions with the Seattle Heart Failure Model, the SPRM was much better at partitioning treatment benefit from ICD therapy (effect size was 2- to 3.6-fold larger for the ICD×SPRM interaction). ICD benefit varied significantly across SPRM-predicted risk quartiles: for all-cause mortality, a+10% increase with ICD therapy in the first quartile (highest risk of death, lowest proportion of sudden death) to a decrease of 66% in the fourth quartile (lowest risk of death, highest proportion of sudden death; p= 0.0013); for sudden death mortality, a 19% reduction in SPRM quartile 1 to 95% reduction in SPRM quartile 4 (p< 0.0001). In symptomatic systolic heart failure patients with a Class I recommendation for primary prevention ICD therapy, the SPRM offers a useful patient-centric tool for guiding shared decision making.

Seattle Heart Failure and Proportional Risk Models Predict Benefit From Implantable Cardioverter-Defibrillators

BackgroundRecent clinical trials highlight the need for better models to identify patients at higher risk of sudden death. ObjectivesThe authors hypothesized that the Seattle Heart Failure Model (SHFM) for overall survival and the Seattle Proportional Risk Model (SPRM) for proportional risk of sudden death, including death from ventricular arrhythmias, would predict the survival benefit with an implantable cardioverter-defibrillator (ICD). MethodsPatients with primary prevention ICDs from the National Cardiovascular Data Registry (NCDR) were compared with control patients with heart failure (HF) without ICDs with respect to 5-year survival using multivariable Cox proportional hazards regression. ResultsAmong 98,846 patients with HF (87,914 with ICDs and 10,932 without ICDs), the SHFM was strongly associated with all-cause mortality (p < 0.0001). The ICD−SPRM interaction was significant (p < 0.0001), such that SPRM quintile 5 patients had approximately twice the reduction in mortality with the ICD versus SPRM quintile 1 patients (adjusted hazard ratios [HR]: 0.602; 95% confidence interval [CI]: 0.537 to 0.675 vs. 0.793; 95% CI: 0.736 to 0.855, respectively). Among patients with SHFM-predicted annual mortality ≤5.7%, those with a SPRM-predicted risk of sudden death below the median had no reduction in mortality with the ICD (adjusted ICD HR: 0.921; 95% CI: 0.787 to 1.08; p = 0.31), whereas those with SPRM above the median derived the greatest benefit (adjusted HR: 0.599; 95% CI: 0.530 to 0.677; p < 0.0001). ConclusionsThe SHFM predicted all-cause mortality in a large cohort with and without ICDs, and the SPRM discriminated and calibrated the potential ICD benefit. Together, the models identified patients less likely to derive a survival benefit from primary prevention ICDs.

Abstract 12090: Seattle Heart Failure Model and Seattle Proportional Risk Model Together Identify Patients Most Likely to Benefit From Primary Prevention ICDs - An NCDR Analysis

Introduction: Risk models are greatly needed to target appropriate patients for implantable cardioverter defibrillators (ICDs) in clinical practice for primary prevention of sudden death. Hypothesis: We hypothesized that the Seattle Heart Failure Model (SHFM) for overall survival and the Seattle Proportional Risk Model (SPRM) for proportional risk of arrhythmic death (AD) would identify National Cardiovascular Data Registry (NCDR) ICD Registry patients most likely to have improved survival with versus without an ICD. Methods: SHFM and SPRM scores were determined for patients with and without ICDs (ICD Registry versus a control group derived from the University of Washington Registry, Italian Heart Failure Registry, Swedish Heart Failure Registry, COMET, Val-HeFT, and PRAISE trials). Multivariable Cox proportional hazards regression was used to evaluate adjusted associations of SPRM and SHFM with survival over 5 years from the Social Security Death Index. Results: Among 98,846 patients (87,914 with ICDs and 10,932 without ICDs), increasing SFHM risk was strongly associated with decreased survival (P&lt;0.0001). Compared with patients having a lower SPRM-predicted proportional risk of AD, patients with a higher predicted proportional AD risk had approximately twice the ICD survival benefit (HR 0.602 [95% CI 0.537-0.675] for SPRM quintile 5 versus HR 0.793 [0.736-0.855] for SPRM quintile 1). The ICD-SPRM interaction was highly significant (Figure). The ICD did not improve adjusted survival versus controls in the 25% of patients with higher predicted survival (SHFM &lt; mean) but a lower proportional AD risk (SPRM &lt; mean) (HR 0.921, 95% CI 0.787-1.08, P=0.31); however, survival in patients with opposite findings (SHFM &gt; mean, SPRM &gt; mean) was greatly improved versus controls (HR 0.599, 95% CI 0.530-0.677, P&lt;0.0001). Conclusions: The SHFM and SPRM scores together identify real-world patients most likely to benefit from primary prevention ICD implantation.

A novel method to predict the proportional risk of sudden cardiac death in heart failure: Derivation of the Seattle Proportional Risk Model

Patients with heart failure are at increased risk of both sudden death and pump failure death. Strategies to better identify those who have greatest net benefit from implantable cardioverter-defibrillator (ICD) implantation could reduce morbidity and maximize cost-effectiveness of ICDs. We aimed to identify baseline variables in patients with cardiomyopathy that are independently associated with a disproportionate fraction of mortality risk attributable to sudden death vs nonsudden death. We used data from 9885 patients with heart failure without ICDs, of whom 2552 died during an average follow-up of 2.3 years. Using commonly available baseline clinical and demographic variables, we developed a multivariate regression model to identify variables associated with a disproportionate risk of sudden death. We confirmed that lower ejection fraction and better functional class were associated with a greater proportion of mortality due to sudden death. Younger age, male sex, and higher body mass index were independently associated with a greater proportional risk of sudden death, while diabetes mellitus, hyper/hypotension, higher creatinine level, and hyponatremia were associated with a disproportionately lower risk of sudden death. The use of several heart failure medications, left ventricular end-diastolic dimension, or NT-pro brain natriuretic peptide concentrations were not associated with a disproportionate risk of sudden death. Several easily obtained baseline demographic and clinical variables, beyond ejection fraction and New York Heart Association functional class, are independently associated with a disproportionately increased risk of sudden death. Further investigation is needed to assess whether this novel predictive method can be used to target the use of lifesaving therapies to populations who will derive greatest mortality benefit .

Can the Seattle Proportional Risk Model Identify Patients With a Greater ICD Benefit in HF-ACTION?

Meta-analysis of primary prevention ICD trials suggests that ICDs decrease sudden death by 60%. Prediction of which heart failure patients are most likely to die of sudden death vs. non sudden death is important to determine who will benefit from an ICD. We developed the Seattle Proportional Risk Model (SPRM) to estimate the percent of deaths that are sudden (AHA 2011). We applied this model to HF-ACTION, a trial designed to evaluate exercise training in ambulatory heart failure (NYHA II-IV, EF35%) patients.