Ryoma Fukuoka1, Takashi Kohno1,2, Shun Kohsaka1, Yasuyuki Shiraishi1, Mitsuaki Sawano1, Takayuki Abe3,4, Yuji Nagatomo5,6, Ayumi Goda2, Atsushi Mizuno7, Keiichi Fukuda1, Ramin Shadman8, Todd F Dardas9, Wayne C Levy9, Tsutomu Yoshikawa5. 1. Department of Cardiology, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo, Japan. 2. Department of Cardiovascular Medicine, Kyorin University School of Medicine, Tokyo, Japan. 3. Biostatistics Unit, Clinical and Translational Research Center, Keio University Hospital, Tokyo, Japan. 4. Yokohama City University School of Data Science, Kanagawa, Japan. 5. Department of Cardiology, Sakakibara Heart Institute, Tokyo, Japan. 6. Department of Cardiology, National Defense Medical College, Saitama, Japan. 7. Department of Cardiology, St. Lukes International Hospital, Tokyo, Japan. 8. Division of Cardiology, Southern California Permanente Medical Group, Los Angeles, CA, USA. 9. Division of Cardiology, University of Washington, Seattle, WA, USA.
Abstract
AIMS: 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). METHODS AND RESULTS: 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). CONCLUSION: 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. Published on behalf of the European Society of Cardiology. All rights reserved.
AIMS: 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 HFpatients hospitalized for acute decompensation, and externally validate the Seattle Proportional Risk Model (SPRM). METHODS AND RESULTS: We consecutively registered 2240 acute HFpatients 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 HFpatients 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). CONCLUSION: 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. Published on behalf of the European Society of Cardiology. All rights reserved.