allopurinol and Heart-Failure--Systolic

Systolic and diastolic myocardial dysfunction has been demonstrated to be associated with an activation of the circulating and local renin-angiotensin-aldosterone system (RAAS), and with a subsequent inappropriately increased production of reactive oxygen species (ROS). While, at low concentrations, ROS modulate important physiological functions through changes in cellular signalling and gene expression, overproduction of ROS may adversely alter cardiac mechanics, leading to further worsening of systolic and diastolic function. In addition, vascular endothelial dysfunction due to uncoupling of the nitric oxide synthase, activation of vascular and phagocytic membrane oxidases or mitochondrial oxidative stress may lead to increased vascular stiffness, further compromising cardiac performance in afterload-dependent hearts. In the present review, we address the potential role of ROS in the pathophysiology of myocardial and vascular dysfunction in heart failure (HF) and their therapeutic targeting. We discuss possible mechanisms underlying the failure of antioxidant vitamins in improving patients' prognosis, the impact of angiotensin-converting enzyme inhibitors or AT1 receptor blockers on oxidative stress, and the mechanism of the benefit of combination of hydralazine/isosorbide dinitrate. Further, we provide evidence supporting the existence of differences in the pathophysiology of HF with preserved vs. reduced ejection fraction and whether targeting mitochondrial ROS might be a particularly interesting therapeutic option for patients with preserved ejection fraction.

Topics: Angiotensin-Converting Enzyme Inhibitors; Antioxidants; Cardiovascular System; Drug Therapy, Combination; Exercise Therapy; Heart Failure, Diastolic; Heart Failure, Systolic; Humans; Hydralazine; Mitochondria; NADPH Oxidases; Nitrates; Nitric Oxide; Nitric Oxide Synthase; Oxidative Stress; Phosphodiesterase Inhibitors; Reactive Oxygen Species; Stroke Volume; Vitamins; Xanthine Oxidase

Previous studies have not extensively examined the association of hyperuricemia and adverse outcomes in systolic heart failure (HF) in relation to xanthine oxidase inhibitor therapy.. The Prospective Randomized Amlodipine Survival Evaluation study included New York Heart Association class IIIB or IV patients with left ventricular ejection fraction <30%. For analysis, the population was divided into uric acid quartiles among nonallopurinol users (2.2-7.1, >7.1-8.6, >8.6-10.4, >10.4 mg/dL) and those using allopurinol. Multivariate Cox regression modeling was performed to identify predictors of mortality. Uric acid quartile and allopurinol groups were referenced to the lowest uric acid quartile.. A total of 1,152 patients were included. In general, patients in the allopurinol group and in the highest uric acid quartile had indicators of more severe HF, including worse renal function and greater proportion of New York Heart Association class IV patients, and greater diuretic use. The allopurinol group and highest uric acid quartile had the highest total mortality (41.7 and 42.4 per 100 person-years, respectively) and combined morbidity/mortality (45.6 and 51.0 per 100 person-years, respectively). Allopurinol use and highest uric acid quartile were independently associated with mortality (hazard ratio [HR] 1.65, 95% CI 1.22-2.23, P = .001 and HR 1.35, 95% CI 1.07-1.72, P = .01, respectively) and combined morbidity/mortality (uric acid quartile 4 vs 1: HR 1.32, 95% CI 1.06-1.66, P = .02; allopurinol use: HR 1.48, 95% CI 1.11-1.99, P = .008).. Elevated uric acid level was independently associated with mortality in patients with severe systolic HF, even when accounting for allopurinol use.

Topics: Aged; Allopurinol; Biomarkers; Enzyme Inhibitors; Female; Follow-Up Studies; Heart Failure, Systolic; Humans; Hyperuricemia; Male; Middle Aged; Morbidity; Prognosis; Proportional Hazards Models; Prospective Studies; Risk Assessment; Risk Factors; Severity of Illness Index; Survival Rate; United States; Uric Acid