Stress echocardiography for assessment of cardiac allograft vasculopathy

Invasive methods as coronary angiography and intravascular ultrasound (IVUS) are still the routine tools for diagnosis of cardiac allograft vasculopathy (CAV). Nevertheless, invasive tests are expensive and not free of risk. Dobutamine stress echocardiography (DSE) emerged as a useful noninvasive tool for assessment of cardiac allograft vasculopathy (CAV). In our study, echocardiographic wall motion abnormalities (WMA) at rest had a sensitivity of 57% (specificity 88%) to detect CAV defined by IVUS and angiography, which was significantly (p < 0.0001) improved to 72% (specificity 88%) by stress testing. Additional M-mode analysis of systolic wall thickening improved the sensitivity of the resting echocardiogram to 72% (specificity 85%), the combined M-mode and 2D-analysis during stress had a sensitivity of 85% (p < 0.0001; specificity 82%). DSE was also useful to predict prognosis: 1.9% of patients with normal, but 27.3% of patients with abnormal 2D-DSE developed cardiac events (heart failure, infarction, death, re-HTX, PTCA) between annual studies (p < 0.0002). No change in serial DSE studies was associated with a low event rate (4%), compared to serial DSE deterioration (29%, p < 0.0014). Based on our experience, we postpone invasive studies for 12-24 months, if DSE is normal or remains unchanged in serial studies. Angiography is used in patients with abnormal or deteriorating DSE. In conclusion, noninvasive DSE provides useful diagnostic and prognostic information. It appears safe to use DSE as a first step of CAV monitoring.