Olprinone hydrochloride is primarily used in the treatment of acute heart failure. It functions as a phosphodiesterase III inhibitor, which helps to increase cardiac output by enhancing myocardial contractility and promoting vasodilation. This leads to reduced cardiac workload and improved blood flow, making it effective in managing symptoms of heart failure such as shortness of breath and fatigue. It is often administered intravenously in clinical settings for rapid action, particularly in patients who do not respond adequately to other heart failure medications. Its application is carefully monitored due to potential side effects like arrhythmias or hypotension.