RESUMO
We performed autonomic function testing in 68 patients, 34 with diabetes mellitus (group A) and 34 without (group B), at 72 h after a first acute myocardial infarction (MI) to determine the prevalence of autonomic dysfunction in these patients. Heart rate (HR) variation during 6 breaths/min obtained from mean of longest RR interval during expiration(E)/mean of shortest RR interval during inspiration (I) (E:I ratio), immediate HR response to standing = RR at 30th beat/RR at 15th beat (30:15 ratio) and postural fall of blood pressure were evaluated. In group A, 25 (78 percent) of 32 patients had an abnormal expiration-inspiration ratio compared with 28 (85 percent) of 33 in group B. Twenty-six (76 percent) patients in group A and 16 (47 percent) in group B had an abnormal 30:15 ratio. Abnormal postural fall of blood pressure was seen in 16 (47 percent) patients in group A compared with ten (29 percent) in group B. During follow-up, four women in group A with an initial autonomic dysfunction died, and in group B, three patients with a normal autonomic function died. Thus, autonomic dysfunction does not seem to contribute to the high mortality among diabetics after an acute MI.
