PRIMARY ANGIOPLASTY IS PREFERRED THERAPY FOR WOMEN AND ELDERLY

PRIMARY ANGIOPLASTY IS PREFERRED THERAPY FOR WOMEN AND ELDERLY with acute myocardial infarction, Gregg Stone, MD, FACC, et al., William Beaumont Hospital, Royal Oak, Michigan and El Camino Hospital, Mountain View, California, conclude in a study presented March 17 at the annual American College of Cardiology scientific session in Anaheim, California. "Compared to tPA, the survival advantage of primary angioplasty was greatest in women...and in patients greater than or equal to 65 years of age," Stone said. The primary angioplasty in myocardial infarction (PAMI) trial compared percutaneous transluminal coronary angioplasty with intravenous thrombolytic therapy using Genentech's Activase tissue plasminogen activator (tPA) for the removal of residual blockages of vessels in myocardial infarction patients. The multicenter, randomized, prospective study included 288 men (145 receiving PTCA, 143 tPA) and 107 women (50 receiving PTCA, 57 tPA). Overall results of the PAMI study data were published in the March 11 New England Journal of Medicine ("The Gray Sheet" March 15, p. 7); that analysis did not specifically look at age and sex. The analysis by Stone et al. show that women and the elderly experienced the greatest survival benefit when treated with PTCA as opposed to tPA. According to Stone, the PAMI data also support previous findings that show that elderly patients and women are at increased risk for in-hospital mortality following myocardial infarction. The study showed patients less than 65 had a low (.8%) in- hospital mortality rate compared to patients 65 and older (10.7%). The hospital mortality rate for women was 9.3% compared to 2.8% for men; the increased mortality for women was partly due to the fact that women were more likely to be older by an average of eight years, have hypertension, diabetes, prior congestive heart failure and to present for treatment later than men. In the angioplasty treatment arm, there was no significant difference in hospital mortality between men treated with PTCA and those treated with tPA (2.1% and 3.5% respectively). However, in women, only 4% of patients treated with PTCA died in the hospital compared to 14% of women who received tPA treatment (p = .075). Percentages of women experiencing reinfarction were not significantly different between the two treatment groups. Women in the tPA treatment arm, however, experienced either in-hospital death or reinfarction in 17.5% of cases compared to 6% in the angioplasty arm (p = .07). Recurrent ischemia was seen in 28.1% of female tPA patients compared to 16% of PTCA patients (p = .14). Men experienced a significantly higher reinfarction rate with tPA than with PTCA (7.7% and 2.8% respectively), a less significant death or reinfarction rate difference between treatment arms than women had (4.8% with PTCA and 9.8% with tPA, p = .11) and a pronounced reduction in recurrent ischemia with PTCA as opposed to tPA (8.2% for PTCA and 28% for tPA). The .8% mortality rate in patients less than 65 years old was the same for both PTCA and tPA treatment groups. However, in patients 65 and older, in-hospital mortality was 5.7% in patients treated with PTCA and 15% in patients treated with tPA (p = .066). For patients 65 or older, reinfarction occurred in 2.9% of PTCA patients and 7.5% of tPA patients (p = .21). In this age range, the combined endpoint of death or reinfarction occurred in 8.6% of PTCA patients as opposed to 20% of patients in the tPA group (p = .048). Recurrent ischemic events in the elderly took place in 8.6% of PTCA patients and 27.5% of tPA patients (p = .003). For patients less than 65 years of age, reinfarction occurred in 2.4% of PTCA patients compared to 5.8% of tPA patients (p = .17); 3.2% of PTCA patients experienced either death or reinfarction compared to 6.7% of tPA patients (p = .21) and 11.2% of PTCA patients experienced recurrent ischemia compared to 28.3% of tPA patients (p = .0007). No patient receiving PTCA treatment had an in-hospital stroke although 2.8% of male tPA patients had a stroke and 5.3% of female tPA patients had a stroke. Young tPA patients had very few strokes (1.7%), and 6.3% of tPA patients 65 or over had strokes. Three of a total of four intracranial bleeds were in women and all four were in patients 65 or older. Stone concluded that compared to treatment with intravenous tPA, PTCA resulted in a reduction in the incidence of in-hospital death and reinfarction, a reduced rate of recurrent ischemia, stroke and intracranial bleeding. The survival advantages were most pronounced in the high-risk population of women and the elderly. Another presentation by Stone based on PAMI data and presented the same day looked at the effect of the location of myocardial infarction on patient outcomes. The results indicated that patients with anterior myocardial infarction treated with PTCA, compared to those treated with tPA, had reduced in-hospital mortality, reinfarction and stroke. On the other hand, patients with non-anterior myocardial infarction showed non-significant differences in in-hospital death and reinfarction rate between the two therapies and the incidence of ventricular fibrillation increased after PTCA compared to tPA.