Cause of death analysis in the NHLBI PTCA Registry: results and considerations for evaluating long-term survival after coronary interventions.

OBJECTIVES: We examined cause of death in relation to age, length of follow-up and other baseline characteristics in patients in the 1985-1986 National Heart, Lung, and Blood Institute Percutaneous Transluminal Coronary Angioplasty (NHLBI PTCA) Registry. BACKGROUND: The manner in which cardiac versus noncardiac mortality of patients with coronary revascularization varies in relation to patient and study characteristics has not been well documented. METHODS: Cause of death determined from a review of 5 years of annual follow-up forms and death certificates was analyzed in 2,127 patients who had coronary angioplasty (mean age 57.6 years) without acute myocardial infarction. RESULTS: Within 5 years of the initial procedure, there were 205 deaths (9.6%), with 52.7% attributed to cardiac causes. Patients with a low baseline ejection fraction, history of hypertension, previous bypass surgery, previous myocardial infarction, inoperable or high surgical risk or multivessel disease had significantly higher 5-year cardiac mortality. Patients with a history of diabetes, congestive heart failure or severe concomitant noncardiac disease had higher rates of both cardiac and noncardiac mortality. As length of follow-up increased, older patients died of noncardiac causes more often than cardiac causes. Age > or = 65 years was a strong independent predictor of 5-year noncardiac mortality (p < 0.001), but not cardiac mortality (p = 0.08). CONCLUSIONS: All-cause mortality rates may be high in elderly revascularized patients, yet cardiac mortality may be less than that expected because of a high risk of noncardiac death. Although all-cause mortality is a more reliable end point than cause-specific mortality, both cardiac and all-cause mortality should be considered in coronary intervention studies involving older patients and long-term follow-up.