Search

Background: The angiography-derived non-hyperemic pressure ratio (angioNHPR) is a novel index of NHPR based on artificial intelligence (AI) that does not require pressure wires. We investigated the diagnostic accuracy of angioNHPR for detecting hemodynamically relevant coronary artery disease., Methods and Results: In this retrospective single-center study, angioNHPR was assessed using the invasive NHPR as the reference standard. An angioNHPR ≤0.89 was defined as indicative of physiologically significant stenosis. Two angiographic projections ≥30° difference in angulation were selected. The lumen and centerline were automatically segmented by the prototype software, allowing for the calculation of the angioNHPR. We assessed 222 vessels from 178 patients. The accuracy of angioNHPR was 76.6% (95% confidence interval [CI] 70.4-82.0), with sensitivity 66.2% (95% CI 54.0-77.0), specificity 81.5% (95% CI 74.3-87.3), positive predictive value 62.7% (95% CI 53.6-70.9), and negative predictive value 83.7% (95% CI 78.6-87.7). The angioNHPR showed good correlation with invasive NHPR (r=0.72; 95% CI 0.64-0.77; P<0.001), and the agreement between angioNHPR and invasive NHPR was -0.01 (limits of agreement: -0.13, 0.11). The area under the curve (AUC) of angioNHPR was 0.81 (95% CI 0.75-0.86), which was significantly higher than that of 2-dimensional quantitative coronary angiography (AUC 0.69; 95% CI 0.62-0.75; P=0.007)., Conclusions: AI-based angioNHPR demonstrates good diagnostic performance using invasive NHPR as the reference standard.

Background: Angiographic fractional flow reserve (angioFFR) is a novel artificial intelligence (AI)-based angiography-derived fractional flow reserve (FFR) application. We investigated the diagnostic accuracy of angioFFR to detect hemodynamically relevant coronary artery disease., Methods and results: Consecutive patients with 30-90% angiographic stenoses and invasive FFR measurements were included in this prospective, single-center study conducted between November 2018 and February 2020. Diagnostic accuracy was assessed using invasive FFR as the reference standard. In patients undergoing percutaneous coronary intervention, gradients of invasive FFR and angioFFR in the pre-senting segments were compared. We assessed 253 vessels (200 patients). The accuracy of angioFFR was 87.7% (95% confidence interval [CI] 83.1-91.5%), with a sensitivity of 76.8% (95% CI 67.1-84.9%), specificity of 94.3% (95% CI 89.5-97.4%), and area under the curve of 0.90 (95% CI 0.86-0.93%). AngioFFR was well correlated with invasive FFR (r=0.76; 95% CI 0.71-0.81; P<0.001). The agreement was 0.003 (limits of agreement: -0.13, 0.14). The FFR gradients of angioFFR and invasive FFR were comparable (n=51; mean [±SD] 0.22±0.10 vs. 0.22±0.11, respectively; P=0.87)., Conclusions: AI-based angioFFR showed good diagnostic accuracy for detecting hemodynamically relevant stenosis using invasive FFR as the reference standard. The gradients of invasive FFR and angioFFR in the pre-stenting segments were comparable.

Background: Little evidence is available regarding the long-term outcome in elderly patients after deferral of revascularization based on fractional flow reserve (FFR)., Methods and results: From the J-CONFIRM registry (long-term outcomes of Japanese patients with deferral of coronary intervention based on fractional flow reserve in multicenter registry), 1,262 patients were divided into 2 groups according to age: elderly and younger patients (aged ≥75 or <75 years, respectively). The primary endpoint was the cumulative 5-year incidence of target vessel failure (TVF), defined as a composite of cardiac death, target vessel-related myocardial infarction (TVMI), and clinically driven target vessel revascularization (CDTVR). Cumulative 5-year incidence of TVF was not significantly different between elderly and younger patients (14.3% vs. 10.8%, P=0.12). Cardiac death occurred more frequently in elderly patients than younger patients (4.4% vs. 0.8%, P<0.001), whereas TVMI and CDTVR did not differ between groups (1.3% vs. 0.9%, P=0.80; 10.7% vs. 10.1%, P=0.80, respectively). FFR values in lesions with diameter stenosis <50% were significantly higher in elderly patients than in younger patients (0.88±0.07 vs. 0.85±0.07, P=0.01), whereas this relationship was not observed in those with diameter stenosis ≥50%., Conclusions: Elderly patients had no excess risk of ischemic events related to the deferred coronary lesions by FFR, although FFR values in mild coronary artery stenosis were modestly different between elderly and younger patients.

Background: This study compared the diagnostic value of myocardial perfusion imaging (MPI) between the rest-stress 99 m Tc-tetrofosmin protocol (Tc/Tc protocol) and simultaneous acquisition rest 99 m Tc-tetrofosmin/stress 201 Tl dual-isotope protocol (SDI protocol) with a semiconductor camera., Methods and results: We retrospectively studied 147 patients who underwent stress MPI using a cadmium-zinc-telluride camera and invasive coronary angiography within a 3-month interval. The Tc/Tc and SDI protocols were used in 59 and 88 patients, respectively. The sensitivity, specificity, and accuracy of the summed difference score in per-patient analysis were 56%, 85%, and 69%, respectively, for the Tc/Tc protocol and 89%, 82%, and 85%, respectively, for the SDI protocol. The area under the receiver operating characteristic curve was significantly better for the SDI than Tc/Tc protocol for the left anterior descending artery (0.836 vs. 0.674; P=0.0380), the left circumflex artery (0.754 vs. 0.599; P=0.0441), and in per-patient analysis (0.875 vs. 0.707; P=0.0135). There was no significant difference in the diagnostic accuracy of the summed stress score for any vessel or in per-patient analysis between the 2 protocols., Conclusions: The SDI protocol had a higher diagnostic accuracy for the detection of coronary ischemia than the Tc/Tc protocol.