["Persistent" angina: rationale for a metabolic approach]

Despite increasing pharmacological and mechanical treatment options, ischemic heart disease continues to be associated with considerable patient mortality and morbidity. The estimates of the direct and indirect costs associated with chronic stable angina amount to billions of dollars. Given the epidemiological and economic magnitude of the problem, the need for more effective therapies is self-evident. Based on current guidelines, the management of ischemic heart disease has progressively broadened to include risk factor modification, patient education, and pharmacological therapy. The latter includes i) classic antianginal agents such as beta-blockers, calcium antagonists, and nitrates, and ii) drugs for secondary prevention, such as aspirin, clopidogrel, statins, and angiotensin-converting enzyme inhibitors. Tailoring therapy to individual needs has become even more challenging because of the marked changes in the clinical profile of patients with chronic ischemic heart disease. Compared with the past, today's patients tend to be older, to have undergone revascularization procedures, and to frequently have associated illnesses, including heart failure and diabetes. Significant progress has been made in recent years in understanding the role of cardiac energy metabolism in the pathogenesis of myocardial ischemia. A better understanding of metabolic derangements associated with ischemia and reperfusion is translating into innovative therapeutic approaches. Optimization of cardiac energy metabolism is based on promoting cardiac glucose oxidation. This has been proved to enhance cardiac function and protect myocardial tissue against ischemia-reperfusion injury. A new class of metabolic agents, known as the 3-ketoacyl coenzyme A thiolase inhibitors (trimetazidine), is able to elicit an increase in glucose and lactate combustion secondary to partial inhibition of fatty acid oxidation, producing clinical benefits in patients with ischemic heart disease.