Cellular mechanisms in congestive heart failure.

There is substantial, although not yet conclusive, evidence that the failing heart is in an energy-depleted state. Such an imbalance between energy production and energy utilization would have important implications for the management of patients with congestive heart failure (CHF), most important of which is that therapeutic measures that increase myocardial energy demand could have long-term detrimental effects on the heart. By increasing energy expenditure, vasoconstrictors and positive inotropic agents could worsen cell damage, exacerbate relaxation abnormalities and promote arrhythmias. Conversely, therapy that improved the balance between energy delivery and energy expenditure might be expected to improve prognosis in CHF. For this reason, vasodilators and reduced inotropic drive to the failing heart could prolong survival in these patients. Further understanding of the energetics of the failing heart will be of considerable importance in the formulation of hypotheses regarding long-term therapy that could be evaluated in controlled clinical trials.