Does Pre-MI Angina Protect against Cardiovascular Complications in Hospitalized Patients?

A case report published in the September issue of Clinical Cardiology notes that several studies have linked preinfarction angina with a lower incidence of complications in hospitalized patients, particularly in older patients and in patients with diabetes. Some studies have suggested that “patients with preinfarction angina have smaller infarcts and a better prognosis than those without angina.”

To learn more about long-term prognosis in this patient population, and also about the mechanism underlying these benefits, the authors studied 290 patients with a diagnosis of a first acute myocardial infarction (MI). Nearly half of the cohort (143) were older than 64 years of age, and nearly one-fourth (68) were diabetic. All patients had no history of angina for more than one week before their first MI, and no evidence of prior structural cardiopathy.

Study participants were assessed for follow-up complications that included “incidence of readmission to the hospital for heart failure, unstable angina, recurrent MI (residual ischemia), or cardiac death including sudden death.” Fifty patients in the elderly group (35%) and 57 patients in the adult group (38.7%) had preinfarction angina in the week before MI; preinfarction angina was present in 27 patients (39.7%) with diabetes and 80 patients without diabetes (36%).

The authors reported that “There were no significant differences in either the adult or the elderly… for the presence or absence of previous angina in association with cardiovascular death, heart failure leading to hospitalization, residual ischemia, or follow-up complications.” Although the researchers noted that there were no significant differences in terms of the presence or absence of previous angina between the diabetic and nondiabetic groups, they reported that “more diabetics presented residual ischemia (unstable angina or recurrent MI) leading to hospitalization than nondiabetics.”

Based on these findings, and keeping mind the limitations of their study (which they noted were those that are common to all retrospective analyses), the authors concluded that “angina within 1 week of a first MI is not associated with a lower incidence of adverse outcomes after initial hospitalization in adult or elderly patients nor in diabetic or nondiabetic patients.”