Congenital heart disease in adults: management of advanced heart failure

Abstract

The number of adults living with congenital heart disease grows annually. The sequelae of congenital heart disease surgery may involve the electrical conduction system, cardiac valves, prosthetic materials, the myocardium, vascular beds, and the nervous system. These sequelae may lead to heart failure. Adults with congenital heart disease develop heart failure as a consequence of: (1) chronic cyanosis, volume overload, and other hemodynamic abnormalities, (2) low cardiac output with outflow obstruction, or (3) acquired cardiac disease superimposed on pre-existing congenital heart disease. Heart failure is characterized by myocardial remodeling in response to injury. It is associated with maladaptive neurohormonal activation, cytokine release, and vasoconstriction leading to sodium and fluid retention and arrhythmias. Angiotensin converting enzyme inhibitors, β-blockers, and spironolactone address these neurohumoral derangements. Digoxin and diuretics may reduce the frequency of hospitalization. Angiotensin-II receptor blockers, warfarin and amiodarone may benefit selected patients, although a survival benefit has not been established. Implantable cardiac defibrillators and atrio-biventricular pacemakers may prolong life in specific groups of patients. Infusions of nesiritide, dobutamine, or milrinone will improve cardiac output and facilitate diuresis. Dobutamine and milrinone may increase mortality due to neurohumoral activation. Pharmaceutical agents under investigation include tumor necrosis factor receptor antagonists and endothelin receptor blockers. Reversible factors that may precipitate heart failure include: unrecognized fluid retention, tachyarrhythmias, systemic viral infection, endocrine abnormalities, alcohol or substance abuse, negative inotropic drugs, and prostaglandin inhibitors. Intensive patient and family education regarding compliance is critical. This provides patients with a greater sense of control and may reduce the frequency of emergency department visits and hospital admissions. Cardiac transplantation improves survival and quality of life for end-stage heart failure patients. A donor shortage and strict inclusion criteria limit this option. This has led to increased use of mechanical cardiac assist devices as bridges to transplant. Once FDA approved, these devices may become an alternative to transplant for select patients. Cardiologists who treat adults with congenital heart disease must consider the underlying cardiac condition leading to heart failure and tailor therapy. Most of the clinical trials, which guide heart failure therapy do not include a significant number of individuals with congenital heart disease.