Combined Coronary CT-Angiography and TAVI-Planning: A Contrast-Neutral Routine Approach for Ruling-Out Significant Coronary Artery Disease

Abstract

Background: Significant coronary artery disease (CAD) is a common finding in patients undergoing transcatheter aortic valve implantation (TAVI). Assessment of CAD prior to TAVI is recommended by current guidelines and is mainly performed via invasive coronary angiography (ICA). In this study we analyzed the ability of coronary CT-angiography (cCTA) to rule out significant CAD (stenosis ≥ 50%) during routine pre-TAVI evaluation in patients with high pre-test probability for CAD. Methods: In total, 460 consecutive patients undergoing pre-TAVI CT (mean age 79.6 ± 7.4 years) were included. All patients were examined with a retrospectively ECG-gated CT-scan of the heart, followed by a high-pitch-scan of the vascular access route utilizing a single intravenous bolus of 70 mL iodinated contrast medium. Images were evaluated for image quality, calcifications, and significant CAD; CT-examinations in which CAD could not be ruled out were defined as positive (CAD+). Routinely, patients received ICA (388/460; 84.3%; Group A), which was omitted if renal function was impaired and CAD was ruled out on cCTA (Group B). Following TAVI, clinical events were documented during the hospital stay. Results: cCTA was negative for CAD in 40.2% (188/460). Sensitivity, specificity, PPV, and NPV in Group A were 97.8%, 45.2%, 49.6%, and 97.4%, respectively. Median coronary artery calcium score (CAC) was higher in CAD+-patients but did not have predictive value for correct classification of patients with cCTA. There were no significant differences in clinical events between Group A and B. Conclusion: cCTA can be incorporated into pre-TAVI CT-evaluation with no need for additional contrast medium. cCTA may exclude significant CAD in a relatively high percentage of these high-risk patients. Thereby, cCTA may have the potential to reduce the need for ICA and total amount of contrast medium applied, possibly making pre-procedural evaluation for TAVI safer and faster.

Bicuspid Aortic Valve Is Associated with Less Coronary Calcium and Coronary Artery Disease Burden

“…Prior studies have shown that CTA allows an exclusion of obstructive CAD in only about 40% of patients with severe AS scheduled for TAVR. These results are in line with our control group and with prior studies [ 9 ] having enrolled almost exclusively patients with tricuspid valves.…”

“…Second, we did not compare the performance of CTA with invasive coronary angiography. CTA is prone to overestimate stenosis severity and >50% obstructive disease in the presence of severe coronary calcification [ 9 ], especially in patients with a CACS above > 400 Agatston Units.…”

“…CTA is routinely performed in patients with severe aortic stenosis before transcatheter aortic valve replacement (TAVR) for procedure planning [ 7 ] for both TAV and BAV [ 8 ]. However, in more than 50% of patients with TAV stenosis, coronary CTA fails to exclude obstructive CAD due to high CACS [ 9 ].…”

Diagnostic Performance of Quantitative Coronary Artery Disease Assessment Using Computed Tomography in Patients with Aortic Stenosis Undergoing Transcatheter Aortic-Valve Implantation

“…We are con rming that all experiments were performed in accordance with relevant guidelines and regulations. For the purpose of the present study, the sample size (n = 100) was aligned to previous studies with comparable hypothesis and baseline characteristics (8- 15,17,18). Consecutive patients with symptomatic, severe aortic stenosis undergoing CT angiography as part of the routine, pre-procedural TAVI work-up starting from 06/2018 were enrolled.…”

“…Whether CTA may serve in this clinical setting in the future, as a rule-out test for CAD is unclear. The diagnostic accuracy of pre-procedural CTA in TAVI patients as compared to ICA with regard to CAD has previously been investigated, with con icting ndings (8)(9)(10)(11)(12)(13)(14)(15).…”