Abstract 2236: Usefulness of 64-Slice Computed Tomography in Patients Undergoing Percutaneous Coronary Intervention of Chronic Total Occlusion
Background. Despite constant technical advances, percutaneous coronary intervention (PCI) of chronic total occlusion (CTO) remains a challenge with procedural success ranging from 65 to 85% in high volume center. MSCT provides information which cannot be obtained with conventional coronary angiography such as: plaque constitution, calcifications and distribution, route and distal run off. A better knowledge of these parameters may influence the approach to such complex PCI, optimize procedural strategy and success. The aim of our study was to evaluate the usefulness of cardiac CT before PCI of CTO.
Methods. All patients with CTO underwent 64-slice CT before the scheduled PCI. We used a scan protocol with 64±0.625mm slice collimation (pitch 0.2), 350 ms (General Electric Lihgtspeed VCT) and 420 ms (Philips Brillance) rotation time and simultaneous (ECG) gating. Patients with heart rates above 65 bpm received intravenous beta-blockade. All CT examinations were performed with retrospective electrocardiogram gating. Exclusion criteria were atrial fibrillation and creatinemia >140 μmol/l.
Results. Sixty patients were included in the study. Mean age was 63.58.5 yrs, 90% were male. On MSCT, the occlusion length was 25.5mm16.5 (33.119.8 on angiography). Calcifications were evaluated as minimal in 42% (26% angio), moderate in 42% (54%) and severe in 1% (12%) of the cases. No calcification was found in 15% (8%). A possible coronary route was identified in 68% (18% on angio), the lumen was relatively visible in 77%, acceptable in 23% and eccentric in 98%. One side branch was observed in 62 %, two in 8% and none in 30% of the CTO. Procedural difficulty was assessed by angio using a scale of 1 (very easy) to 5 (extremely difficult) with a mean rate of 3.540.92 falling to 2.620.81 after reading the MSCT data. MSCT was deemed as extremely useful in 80%, useful in 18% and non useful in 2%. Overall procedural success was achieved in 79% of the CTOs.
Conclusion. MSCT appears to be a new tool for optimising procedural strategy and increasing success rate in CTO angioplasty.