Measures Stratify Mortality Risk for Heart Attack Patients
Autonomic tone, cardiac electrical substrate measures identify patients at high risk
TUESDAY, Dec. 4 (HealthDay News) -- Measures of autonomic tone and cardiac electrical substrate can identify patients at high risk of death after myocardial infarction, according to two studies published in the Dec. 11 issue of the Journal of the American College of Cardiology.
In the first study, Derek V. Exner, M.D., from the University of Calgary in Alberta, Canada, and colleagues examined which factors could stratify risk of serious events after myocardial infarction using data from 322 patients. After a median of 47 months, the investigators found that patients with impaired heart rate turbulence, abnormal T-wave alternans and an ejection fraction less than 0.50 beyond eight weeks were at 5.2-fold higher risk.
In the second study, Gaetano M. De Ferrari, M.D., from the Fondazione IRCCS Policlinico San Matteo in Pavia, Italy, and colleagues examined which factors could stratify risk of serious events after myocardial infarction using data from 244 patients with well-preserved left ventricular function. After a mean follow-up of five years, during which 5.7 percent patients died from cardiovascular causes, they found that depressed baroreflex sensitivity predicted cardiovascular death (relative risk 11.4).
"These new measures have a sound pathophysiological basis," Peter Sleight, M.D., from the University of Oxford in the United Kingdom, writes in an accompanying editorial.