Coronary CTA and CT-FFR reliably detect relevant coronary artery disease pre TAVI in patients without PCI

D. Felbel (Ulm)¹, C. Buck (Ulm)², N. Riedel (Ulm)³, M. Paukovitsch (Ulm)¹, T. Stephan (Ulm)², M. Krohn-Grimberghe (Ulm)¹, J. Mörike (Ulm)¹, B. Gonska (Bad Nauheim)⁴, C. Panknin (Erlangen)⁵, C. Kloth (Ulm)³, M. Beer (Ulm)³, W. Rottbauer (Ulm)¹, D. Buckert (Ulm)^1
1Universitätsklinikum Ulm Klinik für Innere Medizin II Ulm, Deutschland; ²Universitäres Herzzentrum Ulm Ulm, Deutschland; ³Universitätsklinikum Ulm Klinik für Diagnostische und Interventionelle Radiologie Ulm, Deutschland; ⁴Kerckhoff Klinik GmbH Abteilung für Kardiologie Bad Nauheim, Deutschland; ⁵Scientific Collaborations Siemens Healthcare GmbH Erlangen Erlangen, Deutschland

Background:
Diagnostic performance of computed coronary tomography angiography (cCTA) prior to heart valve interventions improved by new-generation CT-scanners and CT-derived fractional flow reserve (FFR). This study assessed whether relevant proximal coronary disease requiring coronary revascularization can be safely detected by combined cCTA and transcatheter aortic valve implantation (TAVI) planning CT including CT-FFR calculation in patients with severe aortic stenosis.

Methods:
101 consecutive patients with successful cCTA combined with TAVI planning CT using a 128-slice dual-source scanner were analyzed. The detection by cCTA including CT-FFR of relevant left main stem stenosis >50% or proximal coronary artery stenosis >70% was compared to invasive coronary angiography (ICA).

Results:
The study comprised 101 consecutive TAVI patients with a median age of 83 [77 - 86] years, a median Society of Thoracic Surgeons (STS) Score of 3.7 [2.4 – 6.1], 48% were male and 54% had known coronary artery disease. Of 15 patients with relevant coronary stenoses, 14 (93%) were detected by cCTA, while false positive results were found in 25 patients. Only in patients with previous stent implantation (PCI), false positive rates (11/29) were increased, and previous stent implantation revealed as the strongest predictor for misclassification (Odds ratio 4.94, 95%-Confidence interval 1.79 – 13.66, p=0.002). In the subgroup without previous PCI, improved classification performance of 88% being mainly due to 11% false positive classifications lead to a negative predictive value of 99%.

Conclusions:
Combined cCTA and CT-FFR with TAVI planning CT by state-of-the-art scanners and protocols can replace routine ICA in TAVI patients due to its safe detection of relevant coronary artery stenosis, however, diagnostic performance of cCTA is only reduced in patients with coronary stents.