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effect as the other types of rejection, with a worse 5-year survival of 49%.71 Treatment of rejection depends on many factors, including the type, grade, time after transplantation, clinical and hemodynamic effect, and baseline immunosuppression There is general agreement that mild rejection does not require specific intervention Moderate rejection usually requires some degree of intensification of immunosuppression, which generally includes an oral or intravenous bolus of corticosteroid, and an increase in regular therapies Any rejection with hemodynamic compromise requires hemodynamic support commensurate with the clinical presentation and aggressive intensification of immunosuppression Cardiac Allograft Vasculopathy CAV is a diffuse, chronic vascular injury to the graft Ultimately ischemia results from circumferential thickening of the vascular intima with stenosis or occlusion (Fig 67.22) Classical clinical signs associated with coronary artery disease are rare in recipients of transplanted hearts Since the transplanted heart is denervated, recipients may not experience characteristic chest pain even in the face of significant myocardial ischemia Consequently the first clinical manifestations may be symptoms of advanced disease, including congestive heart failure, syncope, ventricular arrhythmias, and death CAV is a leading cause of death beyond 3 years after transplantation (see Table 67.3) FIG 67.22 Cardiac allograft vasculopathy (A) Coronary angiography (single plane) demonstrating a smooth-caliber regular lumen (arrows) (B and C) Intravascular ultrasound of the same vessel at the sites indicated by the arrows Despite the normal appearing angiogram, note the difference in intimal thickening reflecting the presence of moderate graft vasculopathy as seen by ultrasound Risk factors for vasculopathy in children are older donor age, older recipient age, donor cigarette use, recipient black race, transplant era, retransplantation and repeated episodes of cellular rejection.72,73 Fig 67.23 illustrates freedom from this complication for the first 17 years after transplantation, with the same data stratified by age shown in Fig 67.24 This is highly dependent on the aggressiveness of screening Coronary angiography remains the gold standard, but it tends to underestimate CAV compared with pathologic examination or intravascular ultrasound (see Fig 67.22) In addition, angiography provides minimal information on the impact of CAV on cardiac function The revised ISHLT grading system for CAV endeavors to take into account functional parameters from invasive measurements or surrogate markers of hemodynamics from echocardiography.74 Once allograft vasculopathy is evident angiographically, short-term mortality is high (Fig 67.25) Kindel et al have described an increased risk of graft loss in the setting of CAV with left ventricular ejection fraction below 45%, right atrial pressure above 12 mm Hg, and/or pulmonary capillary wedge pressure greater than 15 mm Hg.11 FIG 67.23 Freedom from cardiac allograft vasculopathy (CAV) in children after heart transplantation (From the registry of the International Society of Heart and Lung Transplantation J Heart Lung Transplant 2016;35(10):1185–1195.)