642 VALUE OF CORONARY CTA TO RULE OUT OBSTRUCTIVE CORONARY ARTERY DISEASE IN HIGH-RISK PATIENTS CANDIDATES FOR TAVI

Abstract

Abstract Background Coronary computer tomography angiography (CTA) is currently considered a reliable method to rule out obstructive coronary artery disease (O-CAD) before valvular heart surgery in patients with low-intermediate pretest probability. However, its role in excluding O-CAD before transcatheter aortic valve implantation (TAVI) is less well established. Purpose To assess the value of coronary CTA in safely ruling out O-CAD in high-risk patients undergoing TAVI in a tertiary center. Methods and Results We conducted a single-center retrospective study where patients with severe symptomatic aortic stenosis underwent coronary CTA and then invasive coronary angiography (ICA) if indicated, as part of the TAVI planning. All patients were examined with a retrospectively ECG gated CT scan of the heart, followed by a high-pitch-scan of the vasculature access route utilizing a single intravenous bolus of 70 mL iodinated contrast agent, with an average interval of 31.65 (± 42.50) days to ICA. In both coronary CTA and ICA, O-CAD was defined as a ≥ 50% stenosis in an epicardial vessel ≥ 2 mm diameter. Based on coronary CTA, in case of minimal/non O-CAD, invasive ICA was omitted, whereas it was performed in case of obstructive CAD or inconclusive test. Our registry included 163 patients, out-off 28 did not receive coronary CTA for clinical reasons. Thus, 135 patients (87 female – 64%) presenting a mean age of 87.27 (± 1.23) years underwent coronary CTA. Twenty-one (15%) CTA test were judged positive for O-CAD and 25 (18.5%) were inconclusive (and considered as positive). All of these patients underwent ICA and 17/21 (80.95%) and 16/25 (64%) resulted positive for O-CAD, respectively. About the positive O-CAD and inconclusive CTA group, 11/21 (52.38%) and 11/25 (44%) patients were treated with PCI of ostial or proximal/middle segment lesions, respectively. On a per-patient analysis, coronary CTA showed: a specificity of 78.76% (95% CI 70.07% - 85.89%); a positive predictive value of 82.48% (95% CI 76.75% - 87.04%); and the accuracy was 89.38% (95% CI 82.92% - 94.02%). In patients with minimal/non O-CAD, coronary CTA led us to safely avoid invasive ICA in 65.92% (n=89) patients, with no need for additional contrast agent and without occurrence of related adverse events during the procedure and during the follow-up (up to 12 months). Conclusion Pre-procedural coronary CTA may help us to safely rule out O-CAD in an eligible significant proportion of high risk patients undergoing TAVI. Quite the opposite, the added value in the management of O-CAD by CTA is scarce and it remains to be clarified.