Incidence and Predictors of Sudden Cardiac Death in Patients with Diastolic Heart Failure

Introduction: Although it is known that patients with diastolic heart failure are at an increased risk of death, their mode of death has not been clearly defined. We conducted this study to examine the incidence and predictors of sudden cardiac death (SCD) in patients with isolated diastolic heart failure. Methods and Results: Using the Duke Databank for Cardiovascular Disease, we identified patients with a history of congestive heart failure (CHF) and an ejection fraction of greater than 50% who were enrolled in the database from 1995 through 2004. Mode of death was adjudicated by two independent reviewers. Of the 1,941 patients who met our inclusion criteria, 548 (28%) died (40 were SCD). Using a Cox proportional hazards model, five variables were found to be independently associated with a significant increase in the risk of SCD. These variables include diabetes mellitus (P < 0.01), the presence of mild mitral regurgitation (P < 0.01), severity of CHF (P < 0.01), the occurrence of a myocardial infarction within 3 days prior to the date of the index cardiac catheterization (P = 0.01), and severity of coronary artery disease (P = 0.02). Conclusions: SCD is not uncommon in patients with isolated diastolic heart failure. We identified some clinical variables that are associated with a significant increase in the risk of SCD and that may be used in the risk stratification of patients for SCD. Studies are needed to validate our findings.