Impact of invasive management versus noninvasive management on functional status and quality of life following non-Q-wave myocardial infarction: A randomized clinical trial

Background: Multiple studies have examined whether clinical outcomes are improved by invasive management following non-Q-wave myocardial infarction (NQWMI). However, it remains unclear whether functional status and quality of life are affected by an invasive strategy. Methods: Following NQWMI, we randomized 88 patients to invasive management vs noninvasive management. The primary end point was functional status assessed at 12 months using maximal endurance exercise treadmill testing measured in metabolic equivalents. Secondary end points included changes in scores between baseline and 12 months on the Duke Activity Status Index, the Seattle Angina Questionnaire, and the Medical Outcomes Study 36-Item Short-Form Survey. Results: Of the 42 patients in the invasive arm, 83% underwent initial angiography. Of the 46 patients in the noninvasive arm, 91% underwent initial stress testing. Inhospital and 12-month revascularization rates were similar in the 2 arms (24% vs 22%, P ≥ .99;31% vs 30%, P ≥ .99). Maximal endurance exercise treadmill testing was also similar at 12 months (7.8 vs 6.7 metabolic equivalents, P = .24). Patients in the invasive arm showed improved functional status by mean difference in their Duke Activity Status Index scores (4.3 vs -3.5, P = .04). Improvements in angina-specific quality of life for patients in the invasive arm were demonstrated by the Seattle Angina Questionnaire measures of anginal stability (21.6 vs -5.3, P = .02), anginal frequency (22.9 vs 2.3, P = .02), treatment satisfaction (11.2 vs -10.3, P = .02), and disease perception (24.7% vs 10.9%, P = .07). Conclusions: Compared with patients undergoing noninvasive management of NQWMI, patients undergoing invasive management have some measures indicative of improved functional status. © 2005, Mosby, Inc. All rights reserved.