Detection of significant coronary artery stenosis with cardiac dual-source computed tomography angiography in heart transplant recipients.

Present study evaluates clinical feasibility of cardiac dual-source computed tomography angiography (DSCTA) to detect significant coronary stenosis because of chronic allograft vasculopathy (CAV) after heart transplantation (HTX). An overall of 51 consecutive heart transplant recipients (43 men, 8 women, mean age: 52.3 ± 13.6 years) underwent DSCTA 1 ± 2 days before annual routine invasive coronary angiography (ICA). Three patients were excluded from further analysis. Total 714/717 (99.6%) segments in remaining 48 patients were depicted in diagnostic image quality by DSCTA with three vessel segments in two patients being additionally excluded because of motion artefacts. On a segment-based analysis, sensitivity, specificity, and diagnostic accuracy (DA) for detection of significant stenosis were calculated as 100%, 98.9% and 98.9% respectively. On a patient-based evaluation, sensitivity, specificity and DA were 100%, 86.0% and 93.0% respectively for remaining 46 patients. Negative predictive value (NPV) was 100%. DSCTA enables diagnosis and especially the exclusion of significant coronary artery stenosis in patients after HTX with a high NPV. The low rate of excluded vessel segments compared with former studies indicates improvement in image acquisition and robustness of latest scanner technology and thus may make subsequent annual invasive coronary angiography unnecessary.

Determination of pericardial adipose tissue increases the prognostic accuracy of coronary artery calcification for future cardiovascular events.

OBJECTIVES: Pericardial adipose tissue (PAT) is associated with coronary artery plaque accumulation and the incidence of coronary heart disease. We evaluated the possible incremental prognostic value of PAT for future cardiovascular events. METHODS: 145 patients (94 males, age 60 ± 10 years) with stable coronary artery disease underwent coronary artery calcification (CAC) scanning in a multislice CT scanner, and the volume of pericardial fat was measured. Mean observation time was 5.4 years. RESULTS: 34 patients experienced a severe cardiac event. They had a significantly higher CAC score (1,708 ± 2,269 vs. 538 ± 1,150, p < 0.01), and the CAC score was highly correlated with the relative risk of a future cardiac event: 2.4 (1.8-3.7; p = 0.01) for scores >400, 3.5 (1.9-5.4; p = 0.007) for scores >800 and 5.9 (3.7-7.8; p = 0.005) for scores >1,600. When additionally a PAT volume >200 cm(3) was determined, there was a significant increase in the event rate and relative risk. We calculated a relative risk of 2.9 (1.9-4.2; p = 0.01) for scores >400, 4.0 (2.1-5.0; p = 0.006) for scores >800 and 7.1 (4.1-10.2; p = 0.005) for scores >1,600. CONCLUSIONS: The additional determination of PAT increases the predictive power of CAC for future cardiovascular events. PAT might therefore be used as a further parameter for risk stratification.

Coronary calcifications detected by computed tomography are not markers of cardiac allograft vasculopathy.

BACKGROUND: Cardiac allograft vasculopathy (CAV) still limits survival after heart transplantation. Currently available noninvasive tests are of inferior value to detect CAV, and thus invasive coronary angiography (ICA) is frequently performed. Cardiac dual-source computed tomography calcium scoring (DSCTCS) offers the possibility to detect coronary calcifications, which might serve as a noninvasive marker of CAV. This study sought to evaluate its clinical feasibility. METHODS: One hundred sixty-one patients (130 men; 31 women; mean age: 50.5±12.1 years) underwent DSCTCS 1±2 days before annual routine ICA. Mean posttransplant time was 73.7±49.6 months. The results of DSCTCS were compared with ICA. RESULTS: In 100 patients (85 men; 15 women; mean age: 51.5±12.3 years), coronary calcifications were detected, and in 61 patients (45 men; 16 women; mean age: 49.0±11.7 years), coronary calcifications were excluded. ICA excluded CAV in 82 patients (63 men; 19 women; mean age: 48.6±11.9 years). In 79 patients (67 men; 12 women; mean age: 52.5±12.2 years), CAV was detected of whom 11 patients needed stent implantation. No statistically significant difference of DSCTCS in patients without (17.2±29.5; range: 0-190) and with CAV (33.4±66.8; range: 0-385) was observed (P=0.133). Moreover, 4 of 11 (36.4%) severely diseased patients had a calcium score of zero. Sensitivity, specificity, negative predictive value, and positive predictive value for CAV detection (calcium score threshold >0) was calculated as 72.2%, 47.6%, 47.7%, and 57.0%, respectively. Diagnostic accuracy was 59.6%. CONCLUSION: DSCTCS is not a valuable noninvasive modality for CAV detection and thus not recommended in clinical practice. Moreover, we hypothesize that it represents preexisting or de novo traditional coronary atherosclerosis than CAV.