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Acute coronary syndromes (ACS) constitute a spectrum of clinical presentations ranging from unstable angina and non-ST-segment elevation myocardial infarction to ST-segment myocardial infarction. Myocardial ischemia in this context occurs as a result of an abrupt decrease in coronary blood flow and resultant imbalance in the myocardial oxygen supply-demand relationship. Coronary blood flow is further compromised by other mechanisms that increase coronary vascular resistance or reduce coronary driving pressure. The goals of treatment are to decrease myocardial oxygen demand, increase coronary blood flow and oxygen supply, and limit myocardial injury. Treatments are generally divided into “disease-modifying” agents or interventions that improve hard clinical outcomes and other strategies that can reduce ischemia. In addition to traditional drugs such as beta-blockers and inhibitors of the reninangiotensin-aldosterone system, newer agents have expanded the number of molecular pathways targeted for treatment of ACS. Ranolazine, trimetazidine, nicorandil, and ivabradine are medications that have been shown to reduce myocardial ischemia through diverse mechanisms and have been tested in limited fashion in patients with ACS. Attenuating the no-reflow phenomenon and reducing the injury compounded by acute reperfusion after a period of coronary occlusion are active areas of research. Additionally, interventions aimed at ischemic pre- and post-conditioning may be useful means by which to limit myocardial infarct size. Trials are also underway to examine altered metabolic and oxygen-related pathways in ACS. This review will discuss traditional and newer anti-ischemic therapies for patients with ACS, exclusive of revascularization, anti-thrombotic agents, and the use of high-intensity statins.

Heart failure (HF) is a common, disabling, and costly disease. Despite major advances in medical therapy, morbidity and mortality remain high, in part because current pharmacological regimens may not fully address some unique requirements of the heart for energy. The heart requires a continuous supply of energy-providing substrates and amino acids in order to maintain its function. In HF, defects in substrate metabolism and cardiac energy and substrate utilization may contribute to contractile dysfunction. HF is often accompanied by a deficiency in key micronutrients required for unimpeded energy transfer. Correcting these deficits has been proposed as a method to limit or even reverse the progressive myocyte dysfunction and/or necrosis in HF. This review summarizes the existing HF literature with respect to supplementation trials of key micronutrients involved in cardiac metabolism: coenzyme Q10, l-carnitine, thiamine, and amino acids, including taurine. Studies using a broader approach to supplementation are also considered. Although some of the results are promising, none are conclusive. There is a need for a prospective trial to examine the effects of micronutrient supplementation on morbidity and mortality in patients with HF.