Search

Noninvasive stress testing is commonly used for detection of coronary ischemia but possesses variable accuracy and may result in excessive health care costs. This study aimed to derive and validate an artificial intelligence-guided quantitative coronary computed tomography angiography (AI-QCT) model for the diagnosis of coronary ischemia that integrates atherosclerosis and vascular morphology measures (AI-QCT ISCHEMIA) and to evaluate its prognostic utility for major adverse cardiovascular events (MACE). A post hoc analysis of the CREDENCE (Computed Tomographic Evaluation of Atherosclerotic Determinants of Myocardial Ischemia) and PACIFIC-1 (Comparison of Coronary Computed Tomography Angiography, Single Photon Emission Computed Tomography [SPECT], Positron Emission Tomography [PET], and Hybrid Imaging for Diagnosis of Ischemic Heart Disease Determined by Fractional Flow Reserve) studies was performed. In both studies, symptomatic patients with suspected stable coronary artery disease had prospectively undergone coronary computed tomography angiography (CTA), myocardial perfusion imaging (MPI), SPECT, or PET, fractional flow reserve by CT (FFR CT), and invasive coronary angiography in conjunction with invasive FFR measurements. The AI-QCT ISCHEMIA model was developed in the derivation cohort of the CREDENCE study, and its diagnostic performance for coronary ischemia (FFR ≤0.80) was evaluated in the CREDENCE validation cohort and PACIFIC-1. Its prognostic value was investigated in PACIFIC-1. In CREDENCE validation (n = 305, age 64.4 ± 9.8 years, 210 [69%] male), the diagnostic performance by area under the receiver-operating characteristics curve (AUC) on per-patient level was 0.80 (95% CI: 0.75-0.85) for AI-QCT ISCHEMIA , 0.69 (95% CI: 0.63-0.74; P < 0.001) for FFR CT , and 0.65 (95% CI: 0.59-0.71; P < 0.001) for MPI. In PACIFIC-1 (n = 208, age 58.1 ± 8.7 years, 132 [63%] male), the AUCs were 0.85 (95% CI: 0.79-0.91) for AI-QCT ISCHEMIA , 0.78 (95% CI: 0.72-0.84; P = 0.037) for FFR CT , 0.89 (95% CI: 0.84-0.93; P = 0.262) for PET, and 0.72 (95% CI: 0.67-0.78; P < 0.001) for SPECT. Adjusted for clinical risk factors and coronary CTA-determined obstructive stenosis, a positive AI-QCT ISCHEMIA test was associated with aHR: 7.6 (95% CI: 1.2-47.0; P = 0.030) for MACE. This newly developed coronary CTA-based ischemia model using coronary atherosclerosis and vascular morphology characteristics accurately diagnoses coronary ischemia by invasive FFR and provides robust prognostic utility for MACE beyond presence of stenosis. [Display omitted] [ABSTRACT FROM AUTHOR]

The recent development of artificial intelligence–guided quantitative coronary computed tomography angiography analysis (AI-QCT) has enabled rapid analysis of atherosclerotic plaque burden and characteristics. This study set out to investigate the 10-year prognostic value of atherosclerotic burden derived from AI-QCT and to compare the spectrum of plaque to manually assessed coronary computed tomography angiography (CCTA), coronary artery calcium scoring (CACS), and clinical risk characteristics. This was a long-term follow-up study of 536 patients referred for suspected coronary artery disease. CCTA scans were analyzed with AI-QCT and plaque burden was classified with a plaque staging system (stage 0: 0% percentage atheroma volume [PAV]; stage 1: >0%-5% PAV; stage 2: >5%-15% PAV; stage 3: >15% PAV). The primary major adverse cardiac event (MACE) outcome was a composite of nonfatal myocardial infarction, nonfatal stroke, coronary revascularization, and all-cause mortality. The mean age at baseline was 58.6 years and 297 patients (55%) were male. During a median follow-up of 10.3 years (IQR: 8.6-11.5 years), 114 patients (21%) experienced the primary outcome. Compared to stages 0 and 1, patients with stage 3 PAV and percentage of noncalcified plaque volume of >7.5% had a more than 3-fold (adjusted HR: 3.57; 95% CI 2.12-6.00; P < 0.001) and 4-fold (adjusted HR: 4.37; 95% CI: 2.51-7.62; P < 0.001) increased risk of MACE, respectively. Addition of AI-QCT improved a model with clinical risk factors and CACS at different time points during follow-up (10-year AUC: 0.82 [95% CI: 0.78-0.87] vs 0.73 [95% CI: 0.68-0.79]; P < 0.001; net reclassification improvement: 0.21 [95% CI: 0.09-0.38]). Furthermore, AI-QCT achieved an improved area under the curve compared to Coronary Artery Disease Reporting and Data System 2.0 (10-year AUC: 0.78; 95% CI: 0.73-0.83; P = 0.023) and manual QCT (10-year AUC: 0.78; 95% CI: 0.73-0.83; P = 0.040), although net reclassification improvement was modest (0.09 [95% CI: −0.02 to 0.29] and 0.04 [95% CI: −0.05 to 0.27], respectively). Through 10-year follow-up, AI-QCT plaque staging showed important prognostic value for MACE and showed additional discriminatory value over clinical risk factors, CACS, and manual guideline-recommended CCTA assessment. [Display omitted] [ABSTRACT FROM AUTHOR]

Background: Positron emission tomography (PET) is the clinical gold standard for quantifying myocardial blood flow (MBF). Pericoronary adipose tissue (PCAT) attenuation may detect vascular inflammation indirectly. We examined the relationship between MBF by PET and plaque burden and PCAT on coronary CT angiography (CCTA). Methods: This post hoc analysis of the PACIFIC trial included 208 patients with suspected coronary artery disease (CAD) who underwent [15O]H2O PET and CCTA. Low-attenuation plaque (LAP, < 30HU), non-calcified plaque (NCP), and PCAT attenuation were measured by CCTA. Results: In 582 vessels, 211 (36.3%) had impaired per-vessel hyperemic MBF (≤ 2.30 mL/min/g). In multivariable analysis, LAP burden was independently and consistently associated with impaired hyperemic MBF (P = 0.016); over NCP burden (P = 0.997). Addition of LAP burden improved predictive performance for impaired hyperemic MBF from a model with CAD severity and calcified plaque burden (P < 0.001). There was no correlation between PCAT attenuation and hyperemic MBF (r = − 0.11), and PCAT attenuation was not associated with impaired hyperemic MBF in univariable or multivariable analysis of all vessels (P > 0.1). Conclusion: In patients with stable CAD, LAP burden was independently associated with impaired hyperemic MBF and a stronger predictor of impaired hyperemic MBF than NCP burden. There was no association between PCAT attenuation and hyperemic MBF. [ABSTRACT FROM AUTHOR]

Distinct sex-related differences exist in coronary artery plaque burden and distribution. We aimed to explore sex differences in quantitative plaque burden by coronary CT angiography (CCTA) in relation to ischemia by invasive fractional flow reserve (FFR). This post-hoc analysis of the PACIFIC trial included 581 vessels in 203 patients (mean age 58.1 ​± ​8.7 years, 63.5% male) who underwent CCTA and per-vessel invasive FFR. Quantitative assessment of total, calcified, non-calcified, and low-density non-calcified plaque burden were performed using semiautomated software. Significant ischemia was defined as invasive FFR ≤0.8. The per-vessel frequency of ischemia was higher in men than women (33.5% vs. 7.5%, p ​< ​0.001). Women had a smaller burden of all plaque subtypes (all p ​< ​0.01). There was no sex difference on total, calcified, or non-calcified plaque burdens in vessels with ischemia; only low-density non-calcified plaque burden was significantly lower in women (beta: -0.183, p ​= ​0.035). The burdens of all plaque subtypes were independently associated with ischemia in both men and women (For total plaque burden (5% increase): Men, OR: 1.15, 95%CI: 1.06–1.24, p ​= ​0.001; Women, OR: 1.96, 95%CI: 1.11–3.46, p ​= ​0.02). No significant interaction existed between sex and total plaque burden for predicting ischemia (interaction p ​= ​0.108). The addition of quantitative plaque burdens to stenosis severity and adverse plaque characteristics improved the discrimination of ischemia in both men and women. In symptomatic patients with suspected CAD, women have a lower CCTA-derived burden of all plaque subtypes compared to men. Quantitative plaque burden provides independent and incremental predictive value for ischemia, irrespective of sex. We aimed to explore sex differences in quantitative plaque burden by coronary CT angiography in relation to ischemia by invasive fractional flow reserve (FFR). Compared to men, women had lower stenosis severity, fewer adverse plaque characteristics, lower quantitatively plaque burden and fewer abnormal FFR. In multivariable linear regression analysis, there was no sex difference on total, calcified, or non-calcified plaque burdens in vessels with ischemia; only low-density non-calcified plaque burden was significantly lower in women (beta: −0.183, p ​= ​0.035). The addition of quantitative plaque burden to stenosis severity and adverse plaque characteristics improved the discrimination of ischemia irrespective of sex. [ABSTRACT FROM AUTHOR]

This study was designed to assess the prognostic value of pericoronary adipose tissue computed tomography attenuation (PCATa) beyond quantitative coronary computed tomography angiography (CCTA)–derived plaque volume and positron emission tomography (PET) determined ischemia. Inflammation plays a crucial role in atherosclerosis. PCATa has been shown to assess coronary-specific inflammation and is of prognostic value in patients with suspected coronary artery disease (CAD). A total of 539 patients who underwent CCTA and [15O]H 2 O PET perfusion imaging because of suspected CAD were included. Imaging assessment included coronary artery calcium score (CACS), presence of obstructive CAD (≥50% stenosis) and high-risk plaques (HRPs), total plaque volume (TPV), calcified/noncalcified plaque volume (CPV/NCPV), PCATa, and myocardial ischemia. The endpoint was a composite of death and nonfatal myocardial infarction. Prognostic thresholds were determined for quantitative CCTA variables. During a median follow-up of 5.0 (interquartile range: 4.7 to 5.0) years, 33 events occurred. CACS >59 Agatston units, obstructive CAD, HRPs, TPV >220 mm3, CPV >110 mm3, NCPV >85 mm3, and myocardial ischemia were associated with shorter time to the endpoint with unadjusted hazard ratios (HRs) of 4.17 (95% confidence interval [CI]: 1.80 to 9.64), 4.88 (95% CI: 1.88 to 12.65), 3.41 (95% CI: 1.72 to 6.75), 7.91 (95% CI: 3.05 to 20.49), 5.82 (95% CI: 2.40 to 14.10), 8.07 (95% CI: 3.33 to 19.55), and 4.25 (95% CI: 1.84 to 9.78), respectively (p < 0.05 for all). Right coronary artery (RCA) PCATa above scanner specific thresholds was associated with worse prognosis (unadjusted HR: 2.84; 95% CI: 1.44 to 5.63; p = 0.003), whereas left anterior descending artery and circumflex artery PCATa were not related to outcome. RCA PCATa above scanner specific thresholds retained is prognostic value adjusted for imaging variables and clinical characteristics associated with the endpoint (adjusted HR: 2.45; 95% CI: 1.23 to 4.93; p = 0.011). Parameters associated with atherosclerotic burden and ischemia were more strongly associated with outcome than RCA PCATa. Nonetheless, RCA PCATa was of prognostic value beyond clinical characteristics, CACS, obstructive CAD, HRPs, TPV, CPV, NCPV, and ischemia. [Display omitted] [ABSTRACT FROM AUTHOR]

The authors sought to evaluate the impact of ischemic burden reduction after chronic total occlusion (CTO) percutaneous coronary intervention (PCI) on long-term prognosis and cardiac symptom relief. The clinical benefit of CTO PCI is questioned. In a high-volume CTO PCI center, 212 patients prospectively underwent quantitative [15O]H 2 O positron emission tomography perfusion imaging before and three months after successful CTO PCI between 2013-2019. Perfusion defects (PD) (in segments) and hyperemic myocardial blood flow (hMBF) (in ml · min−1 · g−1) allocated to CTO areas were related to prognostic outcomes using unadjusted (Kaplan-Meier curves, log-rank test) and risk-adjusted (multivariable Cox regression) analyses. The prognostic endpoint was a composite of all-cause death and nonfatal myocardial infarction. After a median [interquartile range] of 2.8 years [1.8 to 4.3 years], event-free survival was superior in patients with ≥3 versus <3 segment PD reduction (p < 0.01; risk-adjusted p = 0.04; hazard ratio [HR]: 0.34 [95% confidence interval (CI): 0.13 to 0.93]) and with hMBF increase above (Δ≥1.11 ml · min−1 · g−1) versus below the population median (p < 0.01; risk-adjusted p < 0.01; HR: 0.16 [95% CI: 0.05 to 0.54]) after CTO PCI. Furthermore, event-free survival was superior in patients without versus any residual PD (p < 0.01; risk-adjusted p = 0.02; HR: 0.22 [95% CI: 0.06 to 0.76]) or with a residual hMBF level >2.3 versus ≤2.3 ml · min−1 · g−1 (p < 0.01; risk-adjusted p = 0.03; HR: 0.25 [95% CI: 0.07 to 0.91]) at follow-up positron emission tomography. Patients with residual hMBF >2.3 ml · min−1 · g−1 were more frequently free of angina and dyspnea on exertion at long-term follow-up (p = 0.04). Patients with extensive ischemic burden reduction and no residual ischemia after CTO PCI had lower rates of all-cause death and nonfatal myocardial infarction. Long-term cardiac symptom relief was associated with normalization of hMBF levels after CTO PCI. [Display omitted] [ABSTRACT FROM AUTHOR]

This study aimed to investigate the diagnostic value of comprehensive on-site coronary computed tomography angiography (CCTA) using stenosis and plaque measures and subtended myocardial mass (V sub) for fractional flow reserve (FFR) defined hemodynamically obstructive coronary artery disease (CAD). Additionally, the incremental diagnostic value of off-site CT-derived FFR (FFR CT) was assessed. Prospectively enrolled patients underwent CCTA followed by invasive FFR interrogation of all major coronary arteries. Vessels with ≥30% stenosis were included for analysis. On-site CCTA assessment included qualitative and quantitative stenosis (visual grading and minimal lumen area, MLA) and plaque measures (characteristics and volumes), and V sub. Diagnostic value of comprehensive on-site CCTA assessment was tested by comparing area under the curves (AUC). In vessels with available FFR CT , the incremental value of off-site FFR CT was tested. In 236 vessels (132 patients), MLA, positive remodeling, non-calcified plaque volume, and V sub were independent on-site CCTA predictors for hemodynamically obstructive CAD (p < 0.05 for all). V sub /MLA2 outperformed all these on-site CCTA parameters (AUC = 0.85) and V sub was incremental to all other CCTA predictors (p = 0.02). In subgroup analysis (n = 194 vessels), diagnostic performance of FFR CT and V sub /MLA2 was similar (AUC 0.89 and 0.85 respectively, p = 0.25). Furthermore, diagnostic performance significantly albeit minimally increased when FFR CT was added to on-site CCTA assessment (ΔAUC = 0.03, p = 0.02). In comprehensive on-site CCTA assessment, V sub /MLA2 demonstrated greatest diagnostic value for hemodynamically obstructive CAD and V sub was incremental to all evaluated CCTA indices. Additionally, adding FFR CT only minimally increased diagnostic performance, demonstrating that on-site CCTA assessment is a reasonable alternative to FFR CT. Several novel indices have been proposed to increase the diagnostic performance of coronary computed tomography angiography (CCTA). The diagnostic value of comprehensive on-site CCTA assessment using qualitative and quantitative stenosis and plaque measures and subtended myocardial mass (V sub) for fractional flow reserve (FFR) defined hemodynamically obstructive CAD was assessed in 236 vessels with ≥30% stenosis (132 patients). V sub /MLA2 demonstrated greatest diagnostic value and V sub was incremental to all evaluated CCTA indices. The addition of off-site CT-derived FFR (FFR CT , in 192 vessels) only minimally increased diagnostic performance, demonstrating that on-site CCTA assessment is a reasonable alternative to off-site assessment using FFR CT. [ABSTRACT FROM AUTHOR]

This study compared the performance of the quantitative flow ratio (QFR) with single-photon emission computed tomography (SPECT) and positron emission tomography (PET) myocardial perfusion imaging (MPI) for the diagnosis of fractional flow reserve (FFR)−defined coronary artery disease (CAD). QFR estimates FFR solely based on cine contrast images acquired during invasive coronary angiography (ICA). Head-to-head studies comparing QFR with noninvasive MPI are lacking. A total of 208 (624 vessels) patients underwent technetium-99m tetrofosmin SPECT and [15O]H 2 O PET imaging before ICA in conjunction with FFR measurements. ICA was obtained without using a dedicated QFR acquisition protocol, and QFR computation was attempted in all vessels interrogated by FFR (552 vessels). QFR computation succeeded in 286 (52%) vessels. QFR correlated well with invasive FFR overall (R = 0.79; p < 0.001) and in the subset of vessels with an intermediate (30% to 90%) diameter stenosis (R = 0.76; p < 0.001). Overall, per-vessel analysis demonstrated QFR to exhibit a superior sensitivity (70%) in comparison with SPECT (29%; p < 0.001), whereas it was similar to PET (75%; p = 1.000). Specificity of QFR (93%) was higher than PET (79%; p < 0.001) and not different from SPECT (96%; p = 1.000). As such, the accuracy of QFR (88%) was superior to both SPECT (82%; p = 0.010) and PET (78%; p = 0.004). Lastly, the area under the receiver operating characteristics curve of QFR, in the overall sample (0.94) and among vessels with an intermediate lesion (0.90) was higher than SPECT (0.63 and 0.61; p < 0.001 for both) and PET (0.82; p < 0.001 and 0.77; p = 0.002), respectively. In this head-to-head comparative study, QFR exhibited a higher diagnostic value for detecting FFR-defined significant CAD compared with perfusion imaging by SPECT or PET. [ABSTRACT FROM AUTHOR]

Objective: To determine the impact of right ventricular side branch (RVB) occlusion, during percutaneous coronary interventions (PCIs) of chronic total occlusions (CTOs) of the right coronary artery (RCA), on right ventricular (RV) function.Background: Developments in PCI techniques have expanded PCI CTO feasibility. However, the utilization of dissection and reentry techniques and extensive stent implantation increases the risk of coronary side branch occlusion.Methods: Fifty-four patients (80% male, 63±10years) evaluated with cardiac magnetic resonance imaging (CMR) prior and three months after successful PCI CTO RCA (median: 99days, IQR: 92-105days) were included. Right ventricular end-diastolic volume (RVEDV), end-systolic volume (RVESV), and ejection fraction (RVEF) were quantified on CMR images. Occurrence of RVB occlusion and/or RVB recruitment was assessed using procedural angiograms.Results: RVB occlusion was observed in 12 patients (22%), while RVB recruitment occurred in seven patients (13%). Overall, RVEF was comparable between baseline and follow-up (53.8±5.8 vs. 53.9±5.8%, p=0.95). RVB occlusion was not associated with a significant change in RVEDV or RVEF (156.9±36.3 vs. 162.1±35.5mL, p=0.30 and 54.2±3.9 vs. 52.7±4.4%, p=0.19, respectively); however a trend was observed for an increase of RVESV (72.5±20.0 vs. 77.4±20.7mL, p=0.05) at follow-up. RVB recruitment did not result in a significant improvement of RVEF (55.4±4.6 vs. 56.1±5.3%, p=0.75).Conclusion: RVB occlusion was not associated with a significant decreased RVEF at follow-up, although the results suggested a limited increase of RVESV. [ABSTRACT FROM AUTHOR]

Open surgical repair of an aortic aneurysm requires aortic cross-clamping, resulting in temporary ischemia of all organs and tissues supplied by the aorta distal to the clamp. Major complications of open aneurysm repair due to aortic cross-clamping include renal ischemia-reperfusion injury and postoperative colonic ischemia in case of supra- and infrarenal aortic aneurysm repair. Ischemia-reperfusion injury results in excessive production of reactive oxygen species and in oxidative stress, which can lead to multiple organ failure. Several perioperative protective strategies have been suggested to preserve renal function during aortic cross-clamping, such as pharmacotherapy and therapeutic hypothermia of the kidneys. In this chapter, we will briefly discuss the pathophysiology of ischemia-reperfusion injury and the preventative measures that can be taken to avoid abdominal organ injury. Finally, techniques to minimize the risk of complications during and after open aneurysm repair will be presented. [ABSTRACT FROM AUTHOR]

We sought to investigate the impact of sex on myocardial perfusion changes following chronic total coronary occlusion (CTO) percutaneous coronary intervention (PCI) as measured by [15O]H 2 O positron-emission tomography (PET) perfusion imaging. CTO PCI has been associated with an increase in myocardial perfusion, yet females are less likely to undergo revascularization. As such, data on the impact of sex on myocardial perfusion following CTO PCI is scarce. A total of 212 patients were prospectively enrolled and underwent CTO PCI combined with [15O]H 2 O PET perfusion imaging prior to and 3 months after PCI. Hyperemic myocardial blood flow (hMBF, mL·min−1·g−1) and coronary flow reserve (CFR) allocated to the CTO territory were quantitatively assessed. This study comprised 34 (16 %) females and 178 (84 %) males. HMBF at baseline did not differ between sexes. Females showed a higher increase in hMBF than males (Δ1.34 ± 0.67 vs. Δ1.06 ± 0.74, p = 0.044), whereas post-PCI hMBF was comparable (2.59 ± 0.85 in females vs. 2.28 ± 0.84 in males, p = 0.052). Female sex was independently associated with a higher increase in hMBF after correction for clinical covariates. CFR increase after revascularization was similar in females and males (Δ1.47 ± 0.99 vs. Δ1.30 ± 1.14, p = 0.711). The present study demonstrates a greater recovery of stress perfusion in females compared to males as measured by serial [15O]H 2 O PET imaging. In addition, a comparable increase in CFR was found in females and males. These results emphasize the benefit of performing CTO PCI in both sexes. What is new? • CTO PCI has been associated with an increase in myocardial perfusion, yet females are less likely to undergo revascularization. • We found a greater recovery of stress perfusion in females compared to males after CTO PCI as measured by serial [15O]H 2 O PET imaging, whereas coronary flow reserve was comparable between sexes. • The present study adds to the limited body of evidence on the impact of sex on myocardial perfusion following CTO PCI. What are the clinical implications? • Our findings suggest that recovery of myocardial perfusion following CTO PCI is achievable in both female and male patients. • These results underscore the need to adhere to current guidelines for optimal CTO management in both sexes. • Future studies with standardized preprocedural imaging are warranted to increase our understanding of the impact of sex on changes in myocardial perfusion following CTO PCI. • CTO PCI is associated with an increase in myocardial perfusion, yet females are less likely to undergo revascularization. • We found a greater recovery of stress perfusion in females after CTO PCI as measured by serial [15O]H 2 O PET imaging. • Our findings suggest that recovery of myocardial perfusion following CTO PCI is achievable in both female and male patients. • These results underscore the need to adhere to current guidelines for optimal CTO management in both sexes. • Studies with preprocedural imaging are warranted to increase our understanding of the impact of sex on MBF after CTO PCI. [ABSTRACT FROM AUTHOR]

Left atrial (LA) sphericity has been proposed as a more sensitive marker of atrial fibrillation (AF)-associated atrial remodeling compared to traditional markers such as LA size. However, mechanisms that underlie changes in LA sphericity are not fully understood and studies investigating the predictive value of LA sphericity for AF ablation outcome have yielded conflicting results. The present study aimed to assess correlates of LA sphericity and to compare LA sphericity in subjects with and without AF. Measures of LA size (LA diameter, LA volume, LA volume index), LA sphericity and thoracic anteroposterior diameter (APd) at the level of the LA were determined using computed tomography (CT) imaging data in 293 AF patients (62% paroxysmal AF) and 110 controls. LA diameter (40.1 ± 6.8 mm vs. 35.2 ± 5.1 mm; p < 0.001), LA volume (116.0 ± 33.0 ml vs. 80.3 ± 22.6 ml; p < 0.001) and LA volume index (56.1 ± 15.3 ml/m2 vs. 41.6 ± 11.1 ml/m2; p < 0.001) were significantly larger in AF patients compared to controls, also after adjustment for covariates. LA sphericity did not differ between AF patients and controls (83.7 ± 2.9 vs. 83.9 ± 2.4; p = 0.642). Multivariable linear regression analysis demonstrated that LA diameter, LA volume, female sex, body length and thoracic APd were independently associated with LA sphericity. The present study suggests that thoracic constraints rather than the presence of AF determine LA sphericity, implying LA sphericity to be unsuitable as a marker of AF-related atrial remodeling. • The present study is first to assess left atrial sphericity in a significant number of control subjects. • LA sphericity did not differ between AF patients and controls. • Thoracic constraints rather than the presence of AF determine LA sphericity. • This study suggests that LA sphericity is unsuitable as a marker of AF-related atrial remodeling. [ABSTRACT FROM AUTHOR]

Background: Fractional flow reserve (FFR) computation from coronary computed tomography angiography (CTA) datasets (FFRCT) has emerged as a promising noninvasive test to assess hemodynamic severity of coronary artery disease (CAD), but has not yet been compared with traditional functional imaging.Objectives: The purpose of this study was to evaluate the diagnostic performance of FFRCT and compare it with coronary CTA, single-photon emission computed tomography (SPECT), and positron emission tomography (PET) for ischemia diagnosis.Methods: This subanalysis involved 208 prospectively included patients with suspected stable CAD, who underwent 256-slice coronary CTA, 99mTc-tetrofosmin SPECT, [15O]H2O PET, and routine 3-vessel invasive FFR measurements. FFRCT values were retrospectively derived from the coronary CTA images. Images from each modality were interpreted by core laboratories, and their diagnostic performances were compared using invasively measured FFR ≤0.80 as the reference standard.Results: In total, 505 of 612 (83%) vessels could be evaluated with FFRCT. FFRCT showed a diagnostic accuracy, sensitivity, and specificity of 87%, 90%, and 86% on a per-vessel basis and 78%, 96%, and 63% on a per-patient basis, respectively. Area under the receiver-operating characteristic curve (AUC) for identification of ischemia-causing lesions was significantly greater for FFRCT (0.94 and 0.92) in comparison with coronary CTA (0.83 and 0.81; p < 0.01 for both) and SPECT (0.70 and 0.75; p < 0.01 for both), on a per-vessel and -patient level, respectively. FFRCT also outperformed PET on a per-vessel basis (AUC 0.87; p < 0.01), but not on a per-patient basis (AUC 0.91; p = 0.56). In the intention-to-diagnose analysis, PET showed the highest per-patient and -vessel AUC followed by FFRCT (0.86 vs. 0.83; p = 0.157; and 0.90 vs. 0.79; p = 0.005, respectively).Conclusions: In this study, FFRCT showed higher diagnostic performance than standard coronary CTA, SPECT, and PET for vessel-specific ischemia, provided coronary CTA images were evaluable by FFRCT, whereas PET had a favorable performance in per-patient and intention-to-diagnose analysis. Still, in patients in whom 3-vessel FFRCT could be analyzed, FFRCT holds clinical potential to provide anatomic and hemodynamic significance of coronary lesions. [ABSTRACT FROM AUTHOR]