2007

Mayo Clinic Briefings

Mayo Study Suggests Diagnostic Dysfunction Testing Indicated When Heart Patients Fail to Respond to Standard Treatment

Diastolic dysfunction appears to be nearly as important a factor as low ejection fraction in placing heart patients at risk of heart failure. These are the results of a Mayo Clinic prospective community-based study published in the Journal of the American Medical Association in November 2006 (2006;296:2209-16).

The investigation is the first community study of people known to have heart disease, but who are not necessarily in health crisis or in a medical setting. The study's findings support wider use of Doppler echocardiography to detect diastolic dysfunction in select cases, such as patients with heart failure who do not respond to traditional treatment. This scenario should prompt clinical suspicion that diastolic dysfunction — not just low ejection fraction — is the problem.

For the study, Mayo recruited 556 heart patients in Olmsted County, Minnesota, between 2003 and 2005. They tested both diastolic function and ejection fraction with Doppler echocardiography. More than half the patients with heart failure had preserved ejection fraction of 50% or greater, and isolated diastolic dysfunction was present in more than 40% of cases. Ejection fraction and diastolic dysfunction were independently related to higher levels of B-type natriuretic peptide. At 6 months, mortality was 16% for both preserved and reduced ejection fraction. Heart failure with preserved ejection fraction was associated with a high mortality rate, comparable to that of patients with reduced ejection fraction.