Congestive heart failure is a chronic and debilitating disease responsible for high cardiac morbidity and mortality in the world and is associated with more than 290 000 deaths in the United States each year. Recent advances in heart failure therapy target many of the mechanical and structural aspects of heart failure that are not addressed by drug-based therapies; these include abnormalities in electrical conduction, coronary artery or valvular architecture, and in ventricular size and shape. To target these abnormalities, newer therapies have largely been mechanical and device-based in nature and can be collectively described as interventional therapy. Interventional therapy includes the use of interventional medical therapy, electrical-based devices to augment ventricular function, catheterization-based devices for the treatment of underlying coronary artery disease and valvular disease, machines for the removal of excess fluid, mechanical pumps to assist the ventricles, surgical techniques aimed at reshaping the ventricles, the use of tissue therapies such as stem cell transplantation or complete heart transplant, palliative care, and self-care. This article is the first in a 2-part series that will review interventional heart failure therapy and present the most recent data supporting its use.