Coronary stenosis detection by 16-slice computed tomography in heart transplant patients: comparison with conventional angiography and impact on clinical management.

OBJECTIVES

We sought to find a non-invasive alternative to conventional coronary angiography (CCA) for serial detection and follow-up of coronary stenosis due to cardiac allograft vasculopathy in heart transplant patients.

BACKGROUND

Cardiac allograft vasculopathy is the main factor limiting long-term success of heart transplantation. It is usually detected by CCA. Multislice computed tomography (MSCT) coronary angiography has recently proven effective for the diagnosis of coronary stenosis in non-transplant patients.

METHODS

Fifty-three consecutive heart transplant patients underwent MSCT within 24 h before or after their annual routine CCA. Only angiographic segments >1.5 mm were considered for analysis; the coronary arterial tree was divided into nine segments. Three patients were excluded because of technical failure.

RESULTS

Of the 450 angiographic coronary segments, 432 (96%) were evaluable by MSCT. Of the nine coronary stents in seven patients, only three, including one intrastent restenosis, were correctly evaluated by MSCT, and two intrastent restenoses were missed. Complete analysis of the coronary tree was possible for 44 (88%) of the 50 patients. For detection of coronary stenosis >50%, sensitivity was 83%, specificity 95%, positive predictive value 71%, negative predictive value 95%, and accuracy 93%. In the 22 patients with strictly normal MSCT, no stenosis was found by CCA.

CONCLUSIONS

Our study suggests the following guidelines already applied in our institution: 16-slice MSCT can replace CCA in de novo heart transplant patients and patients with strictly normal MSCT at follow-up. Significant wall or lumen changes observed on annual MSCT or stents require further investigation by CCA.