ABSTRACT
Myocardial bridging (MB) is a congenital anomaly characterized by the intramyocardial coronary course that can cause coronary compression during systole leading to myocardial ischemia, often with the concomitant presence of endothelial dysfunction.Improvements in computed tomography (CT) technology have increased the burden of MB detection during coronary-CT (cCT) but their anatomical and functional assessment is often challenging. A stress-rest myocardial perfusion imaging (MPI) by single-photon emission CT (SPECT) is usually required to decide the correct patient management. However, SPECT has long acquisition protocols, poor spatial resolution, and significant radiation doses for the patient. The recent advances in CT scan technology have allowed the evaluation of stress-rest MPI, representing a promising alternative to SPECT.In this paper, we report six cases of MBs assessed with cCT examination and further evaluated with a stress-rest dynamic-CT MPI and SPECT. A reversible perfusion defect in the left anterior descending (LAD) territory segments potentially due to MB was detected in two of six patients, and they were referred for heart team evaluation.In conclusion, cCT and stress-rest dynamic-CT MPI allowed to detect MBs, evaluate their functional significance, and decide the patients' management in a "one-stop shop" examination. Learning objective: Improvements in computed tomography (CT) technology have increased the burden of myocardial bridging (MB) detection during coronary-CT but their anatomical and functional assessment is often challenging.A stress-rest myocardial perfusion imaging (MPI) by single-photon emission CT (SPECT) is then usually required to decide the correct patient management.Recent advances in CT scan technology have allowed the evaluation of stress-rest MPI, that represent a promising alternative to SPECT.
ABSTRACT
PURPOSE: To evaluate the feasibility, image quality (IQ) and diagnostic performance of third generation 192â¯×â¯2 dual source computer tomography (DSCT) with ultra-high pitch acquisition for trans-catheter aortic valve implantation (TAVI) planning and coronary tree assessment. METHOD: In this prospective study, 223 patients underwent to DSCT for TAVI. Coronary calcium scoring (CCS) was calculated. Attenuation values were measured at aortic levels, femoral and coronary arteries. IQ was evaluate with a 4-point scale. The CT performance, in the assessment of coronary stenosis ≥50 % and ≥70 %, was compared with invasive coronary angiography (ICA), served as reference standard. Aortic annulus (AoA) CT derived area and implanted prosthesis size were correlate with Spearman's test. RESULTS: Attenuation values >400HU were obtain in all segments. IQ median value was ≥ 3. In the assessment of stenosis ≥50 %, on a segment-based analysis, CT sensitivity, specificity, positive and negative predictive values and diagnostic accuracy were 97.6 %, 87.6 %, 64.2 %, 99.0 % and 89.6 %, on patient-based analysis were 97.8 %, 88.8 %, 68.8 %, 99.4 % and 90.6 %, respectively. In the assessment of stenosis ≥70 %, on segment-based analysis, were 88.5 %, 83.8 %, 54.7 %, 96.8 % and 84.8 %, and on patient-based analysis were 92.5 %, 85.8 %, 58.7 %, 98.1 % and 87.0 %, respectively. The CT performed better in the group with lower CCS. A direct correlation was found between AoA CT derived area and prosthesis size. CONCLUSION: DSCT, using a single prospective ECG-triggered ultra-high pitch acquisition, is feasible for TAVI planning and in the assessment of coronary stenosis. CT performed worse in patients with severe coronary calcifications.
