Outcome of acute myocardial infarction: low-tech value in a high-tech era.

The more than 60% reduction in age-adjusted coronary artery disease mortality rates in the past 4 decades represents one of the greatest triumphs of modern medicine. The explanations for this progress are multiple, with various analyses estimating that most of the reduction is attributable to the recognition of coronary risk factors and their appropriate reduction in tens of millions of Americans (1–3). For example, between 1980 and 1990 relatively modest changes in the average serum cholesterol levels of all Americans are estimated to have explained about 33% of the decline in coronary mortality, while reductions in smoking rates and in hypertension have probably contributed another 20% (3). These interventions to reduce risk factors, based mostly on lifestyle changes and, more recently, on medications as well, may appear relatively unexciting in each individual but have huge aggregate implications. At a time when high technology tends to dominate the national consciousness, it is striking that coronary artery bypass graft surgery, percutaneous coronary revascularization, and other acute coronary treatments have been estimated to have a smaller national impact than these “low tech” preventive measures. For example, we estimated that improvements in the care of patients with acute myocardial infarction probably accounted for only about 15% of the overall decline in coronary mortality between 1980 and 1990 (3). Although relatively small changes in risk factors in hundreds of millions of Americans may be the best way to maximize public health impact, the approach to the symptomatic patient will usually incorporate high technology interventions, especially if these interventions are known to be efficacious and worthy of their cost. In this context, the report by Heidenreich and McClellan (4) in this issue of the American Journal of Medicine is especially pertinent, because it provides useful estimates of the recent impact of a variety of interventions (especially aspirin, beta-blockers, angiotensin-converting enzyme inhibitors, thrombolysis, and primary percutaneous transluminal coronary angioplasty) that have been shown to be both efficacious and cost effective in randomized trials of patients with acute myocardial infarction. To put their analyses into perspective, they are estimating the relative contributions of specific therapies for acute myocardial infarction to the 15% or so aggregate contribution that all such therapies have made toward the overall decline in coronary mortality. Their analyses are also useful because they provide hints as to the untapped potential of these interventions to have additional impact if their use could be extended to the full spectrum of patients who should benefit from them. This extrapolation is important because a variety of studies have demonstrated that efficacious and cost-effective cardiac interventions are oftentimes underutilized (5,6) and that extending their use to the appropriate patients who are not receiving them could generate huge benefits for the American public (7). In their analysis, Heidenreich and McClellan estimate that low technology interventions—specifically aspirin, beta-blockers, and angiotensin-converting enzyme inhibitors— explained about 44% of the decline in 30-day mortality after an acute myocardial infarction. By comparison, higher technology interventions, including thrombolysis, primary angioplasty, and secondary angioplasty for patients with indications for the procedure, probably explained about another 32% of the decline. Among the high technology interventions, I have included thrombolysis, not because the intravenous administration of a medication is truly high technology but rather because the most-commonly used agents are the result of recombinant technology. The incremental effectiveness of these agents compared with streptokinase, a medication that has been available for at least two generations of physicians, is relatively small on an absolute basis but nevertheless is probably statistically and clinically significant as well as worth the cost in many patients (8,9). At this point in time, the use of thrombolysis is becoming low technology, as most hospitals have realized that the expeditious administration of this therapy to all eligible patients is the key to improving outcomes. Although further improvements in thrombolytic regimens remain a focus of active investigation and must be encouraged, the incremental benefit of these improvements is likely to be relatively small compared with the benefits Am J Med. 2001;110:221–223. From the Department of Medicine, University of California, San Francisco, School of Medicine, San Francisco, California. Requests for reprints should be addressed to Lee Goldman, MD, Department of Medicine, University of California, San Francisco, 505 Parnassus Avenue, San Francisco, California 94143-0120.