transplantation include terminal valvular lesions and congenital anomalies that are not amenable to other surgical or medical therapy. Symptoms include severely limited physical activity and shortness of breath with limited activity or at rest. Recipients are usually < 60 years old, should be healthy otherwise or have organ dysfunctions that are reversible after heart transplantation, and should be compliant with medical instructions.

Cardiovascular System

Patients with end-stage cardiac disease have low cardiac outputs and high filling pressures despite optimal medical management. The initial response to left ventricular dysfunction is an increase in left ventricular end-diastolic volume; this may temporarily restore stroke volume at the cost of an increase in left atrial pressure. Eventually right atrial pressure will increase also, leading to the classic signs and symptoms of congestive heart failure. In addition, the systemic vascular resistance may increase in an attempt to maintain blood pressure. Atrial arrhythmias are common, and some patients with ventricular arrhythmias may have received an automatic implantable cardiac defibrillator (AICD).

Preoperative evaluation should include right and left heart catheterization to evaluate the pulmonary circulation and accurately determine intracardiac pressures. A pulmonary vascular resistance > 6 Wood units is a contraindication for heart transplantation because it frequently leads to failing of the right ventricle of the newly transplanted heart; these patients may be candidates for combined heart-lung transplantation. Moderate increases in pulmonary vascular resistance are usually tolerated if the transplanted heart functions well.

The dilated cardiomyopathy can lead to mural thrombi, which may be treated with chronic anticoagulation. Coronary angiography may determine the presence of treatable coronary lesions. Patients may receive pharmacologic support, frequently consisting of a combination of vasodilators and inotropic agents. Alternatively, a circulatory assist device may be in place (intraaortic balloon counterpulsation, ventricular assist device, artificial heart). Importantly, the prolonged low cardiac output and venous congestion will affect the function of other organs, and therefore all organ systems have to be evaluated preoperatively.

Pulmonary System

Prolonged left ventricular dysfunction results in increased left atrial and pulmonary venous pressure, which leads to an increase in pulmonary vascular resistance caused by hypertrophy of the musculature of the pulmonary arteries. The increase in left atrial pressure also results in an increase in lung water, causing ventilation/perfusion mismatch, increased airway resistance, decreased lung compliance, and increased work of breathing. Pleural effusions will reduce functional residual capacity and possibly further impair oxygenation.

Hepatic System

Chronic passive congestion of the liver may result in a reduced production of coagulation factors and other proteins. In addition, drug metabolism may be altered.

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