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724 ACtIff. CARE. HANDBOOK FOR PHYSICAL THFRAIlISTS

With myocardial depression, the transplanted heart may be affected

temporarily by bradycardia, decreased diastOlic compliance, diminished systOlic function, and impaired contractility.s.u Other potential complications after heart transplant include mediastinal bleeding, cyclosporine-induced hypertension, post-transplant diabetes, thrombosis or leakage of anastOmosis, right heart failure, biventricular heart failure, pulmonary hypertension, pericardial effusion, and renal dysfunction.5.IO.14.22 Bivenrricular failure is a potential complication that is seen in the first 24-48 hours after transplantation.

Most patients have some degree of pulmonary hypertension becallse of

native left ventricular failure. Right heart failure is the most common

calise of cardiac dysfunction postoperatively." It may be caused by a

pre-existing elevated I'VR, donor size mismatch in which the donor

heart is too small for the recipient, long ischemic time of more than 4

hours, and acute rejection.22 Clinical evidence of right ventricular heart

failure includes hypotension, low cardiac output, an elevated central

venous pressure, and low urinary output. tJ Right atrial pressures, pulmonary artery pressure, PVR, cardiac output, and signs of right-sided heart failure are monitOred c1osely.s Medications, such as isoproterenol

hydrochloride or miirinone, are used to reduce pulmonary pressures

and make it easier for the right heart to pumpIl

Many cardiac transplant recipients have pre-existing renal insufficiency due to their low cardiac output, congestive heart failure, and long-term diuretic use.s.n After transplantation, cardiopulmonary

bypass and the use of cyclosporine, which is a nephrotoxic agent, can

cause renal failure in rhe transplant recipienr.s Dopamine is administered ro improve renal blood flow, and diuretics are used to maintain adequate urine output.s In addition, intravenous cyclosporine may be

held postoperatively, and, instead, less-nephrotoxic agents may be

administered.22

Heart transplant recipients have an increased risk of excessive

postoperative bleeding and cardiac tamponade.1J Owing ro chronic

congestive heart failure, patients usually have passive liver congestion,

which increases the risk of bleeding." Many patients also receive

anticoagulation therapy preoperatively to prevent thrombus formation. However, inadequate heparin reversal may occur and, depending on the severity of anticoagulation, treatment includes transfusion of

platelets or ftesh-frozen plasma."

Objective characteristics of acute rejection specific to cardiac

transplant recipients include new cardiac arrhythmias, hypotension,

pericardia I friction rub, ventricular S3 gallop, decreased cardiac Out-