Noninvasive detection of coronary allograft vasculopathy by myocardial contrast echocardiography

Background Noninvasive detection of coronary allograft vasculopathy is still challenging. To determine the accuracy of myocardial contrast echocardiography (MCE) in detecting coronary allograft vasculopathy after heart transplantation, we studied 35 asymptomatic patients (30 men, aged 46 +/- 12.7 years) with normal left ventricular function. Methods: Patients underwent MCE with continuous contrast (perfluorocarbon-exposed sonicated dextrose albumin) administration. Images were obtained at baseline and during peak dobutamine (up to 40 mg/kg/min) with intermittent harmonic imaging. Areas failing to increase contrast enhancement during peak stress were regarded as abnormal. Coronary artery obstructions greater than 50% at angiography were considered significant. Results. Seven out of 10 patients with coronary artery disease had a positive MCE and one patient with a positive MCE had no angiographically detected disease (sensitivity = 70%, specificity = 96%, accuracy = 88.6%). Agreement between the vascular territory and perfusion defects was good for the left anterior descending coronary artery (kappa = 0.56), but not for other arteries. Although 5 patients had multivessel disease, multiple perfusion defects were detected in only one patient. Conclusion: MCE showed good accuracy in detecting the presence of coronary allograft vasculopathy after heart transplantation; however, it failed to identify the extent of the disease.