ABSTRACT Rationale , aims, and objectives: Patients covered by the Taiwan National Health Insurance (NHI) program are eligible to receive an implantable cardioverter/defibrillator (ICD) if they had heart failure (HF) or were determined to be at high risk of sudden cardiac death (SCD). The aim of the study was designed to evaluate ICD recipient prognoses with respect to contributory risks. Methods: From the NHI research database, 2194 patients in Taiwan who received an ICD during the 11 year period 2004-2014 was identified and then assigned to either the no heart failure group (NHF, N=978) or the heart failure group (HF, N=1160). Sub-groups of the NHF subjects analyzed further based on the absence (NHFA, n=383) or presence (NHFP, n=595) of observed cardiac arrhythmias. The mortality rates were reported and survival trends were compared between groups. Results: The mean age of these patients was 61.8+/-15.2 years (men 69.2%). The HF group was older, (65 vs 58) and had significantly more comorbidities. Pharmaceutical and medical resource utilization was also uniformly higher within the HF group. The 30 day (1.8%) and one year (16.6%) mortality rates among the HF patients were 3-4 times higher than in the NHF group. A coexistent major diseases score was constructed and these analyses indicated the disease score was consistently associated with a progressive mortality risk in ICD recipients overall. Conclusions: Of those receiving ICDs, the prognosis for HF patients is poorer than for those in the NHF group which most likely reflects the fact that the HF patients were generally older with more complicated medical conditions.