Prediction of outcome in late-stage cardiomyopathy

In coronary artery disease the coronary arteries do not provide adequate blood flow to the heart muscle, often because of fatty plaques lining the vessels. Idiopathic dilated cardiomyopathy is characterized by enlargement of the heart, poor function of the heart muscle, and congestive heart failure (inadequate heart contractions, leading to lung congestion). Eighty patients with coronary artery disease and 53 with idiopathic dilated cardiomyopathy were followed for an average of 29 months to determine which disease characteristics are associated with outcomes. These patients had been referred because of failure to respond adequately to treatments, and were representative of patients who might be candidates for heart transplant. Among these patients, the fraction of blood successfully ejected during a contraction of the heart, the so-called left-ventricular ejection fraction, did not correlate with poor prognosis. This is in sharp contrast to other studies, which have reported that this factor had significant prognostic value. The primary factors which contributed to mortality were a resting systolic blood pressure (during heart contraction) less than 120 millimeters of mercury (mm Hg), X-ray evidence of heart congestion, age over 64, and evidence of coronary artery disease. The patients were given a questionnaire that asked about common symptoms and the performance of everyday chores. It is worthy of note that for patients with dilated cardiomyopathy, this questionnaire proved to be a more effective predictor of survival than any of the more objective factors analyzed. For patients with ischemic heart problems resulting from coronary artery disease, the questionnaire had no such predictive power. Although blood pressure monitoring is recommended because of its high prognostic value, it is uncertain to what degree health improvements might be achieved through management of hypertension. The subjective self-appraisal of patients with idiopathic dilated cardiomyopathy should be considered quite seriously, as this seems to be a better predictor of outcome than more objective measures. (Consumer Summary produced by Reliance Medical Information, Inc.)