A.J.Conrad Smith

Geriatric patients with acute myocardial infarction: Cardiac risk factor profiles, presentation, thrombolysis, coronary interventions, and prognosis

Elderly patients have a higher mortality after acute myocardial infarction (MI) yet are treated less aggressively than younger patients. To determine (l) the risk-factor profiles, (2) presentation, (3) management, and (4) hospital outcomes for the elderly (> or = 75 years) compared with middle aged (66 to 74 years) and younger (< or = 65 years) patients in the 1990s, we studied 561 consecutive patients with acute MI. Compared with younger patients, the elderly more frequently had congestive heart failure (40 percent vs 14 percent; p < 0.00001) and non-Q wave infarctions (76 percent vs 56 percent; p < 0.005), received thrombolysis (9 percent vs 34 percent; p < 0.0001), and underwent catheterization (35 percent vs 73 percent; p < 0.00001), percutaneous transluminal coronary angioplasty (9 percent vs 31 percent; p < 0.0002), and coronary artery bypass grafting (5 percent vs 15 percent; p < 0.03) less frequently. Those who did not receive thrombolysis all had contraindications. Mortality was higher in the elderly (19 percent vs 5 percent; p < 0.004), especially among those who did not receive thrombolysis (20 percent vs 7 percent; p < 0.03). Multivariate predictors of mortality included age, and congestive heart failure. In addition, when clinical course and management variables were considered, use of the intraaortic balloon pump was a predictor of mortality, whereas undergoing coronary angiography was a negative predictor (relative risk, 0.3; 95 percent confidence intervals, 0.1 to 0.6).

Do gender-based differences in presentation and management influence predictors of hospitalization costs and length of stay after an acute myocardial infarction?

Previous studies have reported conflicting results on gender differences in the management of acute myocardial infarction (AMI) and have not evaluated hospital length of stay or costs. To determine gender-based differences in presentation, management, length of stay, costs, and prognosis after AMI, we studied 561 patients with AMI. Women were older, had systemic hypertension, diabetes mellitus, and a non-Q-wave AMI more frequently, whereas more men smoked cigarettes. Predictors of coronary angiography were: male gender (RR 1.9; 95% CI 1.2 to 3.1), chest pain at presentation (RR 1.8; 95% CI 1.0 to 3.3), recurrent angina (RR 4.1; 95% CI 2.5 to 6.8), admission via the emergency room (RR 0.2; 95% CI 0.1 to 0.3), and younger age. Gender did not predict mortality. Among presenting features, the predictors of length of stay were diabetes, prior coronary bypass and prior coronary angioplasty in men, and age alone in women. Pulmonary edema and need for coronary bypass during the hospital course were predictors of length of stay in men only. Among presenting features, predictors of cost were diabetes in men and congestive heart failure in women. Predictors of cost during hospitalization for men were pulmonary edema, coronary angiography, intraaortic balloon pump use, and coronary bypass; for women, they were peak levels of creatine kinase and coronary bypass. Thus, predictors of length of stay and hospitalization costs differ based on gender. Efforts at cost containment may need to be gender-specific.

Transient thrombotic state after abrupt discontinuation of heparin in percutaneous coronary angioplasty

Clinical and biochemical evidence of a rebound phenomenon after discontinuing thrombin inhibitors has been reported in patients with unstable angina. To investigate if a similar phenomenon occurs in patients undergoing coronary angioplasty, 14 patients were prospectively studied during and after discontinuation of heparin infusion. A transient thrombotic state identified by a significant increase in a polypeptide fragment and fibrinopeptide A was observed 3 hours after abruptly discontinuing heparin infusion. This observation may be clinically important in managing patients after coronary angioplasty.