The potential use of ECG-based prognostic instruments in clinical trials and cost-effectiveness analyses of new therapies in acute cardiac ischemia

The dramatic improvements in outcomes in acute cardiac ischemia because of therapeutic advances has led to "diminishing returns" with increasingly int ensive therapies. This article explores the potential of electrocardiograph (ECG)-based prognostic instruments to identify patients likely to benefit from intense regimens, even in the absence of overall average benefit in th e population, with 2 clinical examples: 1) Reperfusion therapy in acute myo cardial infarction (AMI); and 2) anticoagulation/antiplatelet therapy in un stable angina. Based on previously developed, EGG-based prognostic instrume nts we explored the distribution of potential benefits in individual patien ts from increasingly intense therapy in both AMI and unstable angina. Predi ctions were obtained on community-based patient samples with both AMI and u nstable angina to examine the distribution of effectiveness and cost-effect iveness. For both AMI and unstable angina, much of the benefit of intensify ing therapy can be obtained by targeting a subgroup of patients that can be identified in multivariable dimensions hy clinical and ECG characteristics . Treatment of these patients with more potent agents (such as hirudin or t he glycoprotein inhibitors in unstable angina) is likely to be both effecti ve and cost-effective. However, treatment of "low benefit" patients is unli kely to be effective or cost-effective, and some candidates for therapy are more likely to be harmed, than to benefit, by the more intensive regimens. Multivariable stratification can improve clinical and economic outcomes in acute cardiac ischemia, particularly when such models help identify "high benefit" patients early in their clinical course. Additionally, using valid ated models in the planning and execution of clinical trials of new therapi es can improve the power of the trial and help target the therapies to pati ents mc,st likely to benefit.