Explore the vast range of titles available.

Objectives We aimed to assess the prevalence of coexistence of coronary microvascular dysfunction (CMD) in patients with intermediate epicardial stenosis and to explore coronary computed tomography angiography (CCTA)–derived lesion-, vessel-, and cardiac fat–related characteristic findings associated with CMD. Methods A retrospective cross-sectional single-center study included a total of 177 patients with intermediate stenosis in the left anterior descending artery (LAD) who underwent CCTA and invasive physiological measurements. The 320-slice CCTA analysis included qualitative and quantitative assessments of plaque, vessel, epicardial fat volume (ECFV) and epicardial fat attenuation (ECFA), and pericoronary fat attenuation (FAI). CMD was defined by the index of microcirculatory resistance (IMR) ≥ 25. Results In the entire cohort, median fractional flow reserve (FFR) and median IMR values were 0.77 (0.69–0.84) and 19.0 (13.7–27.7), respectively. The prevalence of CMD was 32.8 % (58/177) in the total cohort. The coexistence of CMD and functionally significant stenosis was 34.3 % (37/108), whereas CMD in nonsignificant intermediate stenosis was 30.4 % (21/69). CMD was significantly associated with greater lumen volume ( p = 0.031), greater fibrofatty and necrotic component (FFNC) volume ( p = 0.030), and greater ECFV ( p = 0.030), but not with FAI ( p = 0.832) and ECFA ( p = 0.445). On multivariable logistic regression analysis, vessel volume, vessel lumen volume, lesion remodeling index, ECFV, and lesion FFNC volume were independent predictors of CMD. Conclusions The prevalence of CMD was about one-third in patients with intermediate stenosis in LAD regardless of the presence or absence of functional stenosis significance. The integrated CCTA assessment may help in the identification of CMD. Key Points • The coexistence of coronary microvascular dysfunction (CMD) and functionally significant stenosis was 34.3 %, whereas CMD in nonsignificant intermediate stenosis was 30.4 %. • Coronary computed tomography angiography (CCTA)-derived CMD characteristics were vessel volume, vessel lumen volume, remodeling index, epicardial fat volume, and fibrofatty necrotic core volume. • Integrated CCTA assessment may help identify the coexistence of CMD and epicardial stenosis.

Limited data are available regarding comparative prognosis after percutaneous coronary intervention (PCI) versus deferral of revascularization in patients with intermediate stenosis with abnormal fractional flow reserve (FFR) but preserved coronary flow reserve (CFR). From the International Collaboration of Comprehensive Physiologic Assessment Registry (NCT03690713), a total of 330 patients (338 vessels) who had coronary stenosis with FFR ≤ 0.80 but CFR > 2.0 were selected for the current analysis. Patient-level clinical outcome was assessed by major adverse cardiac events (MACE) at 5 years, a composite of all-cause death, target-vessel myocardial infarction (MI), or target-vessel revascularization. Among the study population, 231 patients (233 vessels) underwent PCI and 99 patients (105 vessels) were deferred. During 5 years of follow-up, cumulative incidence of MACE was 13.0% (31 patients) without significant difference between PCI and deferred groups (12.7% vs. 14.0%, adjusted HR 1.301, 95% CI 0.611–2.769, P  = 0.495). Multiple sensitivity analyses by propensity score matching and inverse probability weighting also showed no significant difference in patient-level MACE and vessel-specific MI or revascularization. In this hypothesis-generating study, there was no significant difference in clinical outcomes between PCI and deferred groups among patients with intermediate stenosis with FFR ≤ 0.80 but CFR > 2.0. Further study is needed to confirm this finding. Clinical Trial Registration: International Collaboration of Comprehensive Physiologic Assessment Registry (NCT03690713; registration date: 10/01/2018).

To evaluate the differential associations of high-risk plaque characteristics (HRPC) with resting or hyperemic physiologic indexes (instantaneous wave-free ratio [iFR] or fractional flow reserve [FFR]), a total of 214 vessels from 127 patients with stable angina or acute coronary syndrome who underwent coronary computed tomography angiography (CCTA) and invasive physiologic assessment were investigated. HPRC were classified into quantitative (minimal luminal area < 4 mm 2 or plaque burden ≥ 70%) and qualitative features (low attenuation plaque, positive remodeling, napkin ring sign, or spotty calcification). Vessels with FFR ≤ 0.80 or iFR ≤ 0.89 had significantly higher proportions of HRPC than those with FFR > 0.80 or iFR > 0.89, respectively. FFR was independently associated with both quantitative and qualitative HRPC, but iFR was only associated with quantitative HRPC. Both FFR and iFR were significantly associated with the presence of ≥ 3 HRPC, and FFR demonstrated higher discrimination ability than iFR (AUC 0.703 vs. 0.648, P  = 0.045), which was predominantly driven by greater discriminating ability of FFR for quantitative HRPC (AUC 0.832 vs. 0.744, P  = 0.005). In conclusion, both FFR and iFR were significantly associated with CCTA-derived HRPC. Compared with iFR, however, FFR was independently associated with the presence of qualitative HRPC and showed a higher predictive ability for the presence of ≥ 3 HRPC.

Although several large trials that included African American patients with hypertension have demonstrated the superiority of diuretics as an initial monotherapy, its applicability to other ethnicities remains questionable. The purpose of this study was to investigate whether diuretics as first-line antihypertensive medications are superior to other classes of drugs in the Korean population. Using the Korean National Health Insurance Service database, we analyzed 95,201 Korean hypertensive patients without prior history of cardiovascular disease who started a single antihypertensive drug between January 2002 and December 2017. The primary endpoint was a composite of cardiovascular death, myocardial infarction and stroke. Each endpoint was compared among five classes of antihypertensive drugs [diuretics, angiotensin-converting enzyme inhibitors (ACEIs), angiotensin receptor blockers (ARBs), calcium channel blockers (CCBs), and beta-blockers (BBs)]. In multivariable Cox analysis, diuretics were superior to ACEIs (hazard ratio [HR], 1.58-2.01), inferior to ARBs (HR, 0.37-0.43) and similar to CCBs and BBs for the primary endpoint. Similar findings were obtained for all-cause and cardiovascular mortality and stroke. This result was consistently observed in the longer treatment group and in the propensity score-matched pairs. In Korean hypertensive patients without cardiovascular disease, initiation with diuretics could not be superior to other medications, but rather inferior to ARBs in preventing adverse cardiovascular outcomes. Randomized studies are needed to confirm our results.

Background Considering the nature of diabetes mellitus (DM) in coronary artery disease, it is unclear whether complete revascularization is beneficial or not in patients with DM. We investigated the clinical impact of angiographic complete revascularization in patients with DM. Methods A total of 5516 consecutive patients (2003 patients with DM) who underwent coronary stenting with 2nd generation drug-eluting stent were analyzed. Angiographic complete revascularization was defined as a residual SYNTAX (SYNergy between percutaneous coronary intervention with TAXus and cardiac surgery) score of 0. The patient-oriented composite outcome (POCO, including all-cause death, any myocardial infarction, and any revascularization) and target lesion failure (TLF) at three years were analyzed. Results Complete revascularization was associated with a reduced risk of POCO in DM population [adjusted hazard ratio (HR) 0.70, 95% confidence interval (CI) 0.52–0.93, p = 0.016], but not in non-DM population (adjusted HR 0.90, 95% CI 0.69–1.17, p = 0.423). The risk of TLF was comparable between the complete and incomplete revascularization groups in both DM (adjusted HR 0.75, 95% CI 0.49–1.16, p = 0.195) and non-DM populations (adjusted HR 1.11, 95% CI 0.75–1.63, p = 0.611). The independent predictors of POCO were incomplete revascularization, multivessel disease, left main disease and low ejection fraction in the DM population, and old age, peripheral vessel disease, and low ejection fraction in the non-DM population. Conclusions The clinical benefit of angiographic complete revascularization is more prominent in patients with DM than those without DM after three years of follow-up. Relieving residual disease might be more critical in the DM population than the non-DM population. Trial registration The Grand Drug-Eluting Stent registry NCT03507205.

ObjectivesWe explored the anatomical, plaque, and hemodynamic characteristics of high-risk non-obstructive coronary lesions that caused acute coronary syndrome (ACS).MethodsFrom the EMERALD study which included ACS patients with available coronary CT angiography (CCTA) before the ACS, non-obstructive lesions (percent diameter stenosis < 50%) were selected. CCTA images were analyzed for lesion characteristics by independent CCTA and computational fluid dynamics core laboratories. The relative importance of each characteristic was assessed by information gain.ResultsOf the 132 lesions, 24 were the culprit for ACS. The culprit lesions showed a larger change in FFRCT across the lesion (ΔFFRCT) than non-culprit lesions (0.08 ± 0.07 vs 0.05 ± 0.05, p = 0.012). ΔFFRCT showed the highest information gain (0.051, 95% confidence interval [CI] 0.050–0.052), followed by low-attenuation plaque (0.028, 95% CI 0.027–0.029) and plaque volume (0.023, 95% CI 0.022–0.024). Lesions with higher ΔFFRCT or low-attenuation plaque showed an increased risk of ACS (hazard ratio [HR] 3.25, 95% CI 1.31–8.04, p = 0.010 for ΔFFRCT; HR 2.60, 95% CI 1.36–4.95, p = 0.004 for low-attenuation plaque). The prediction model including ΔFFRCT, low-attenuation plaque and plaque volume showed the highest ability in ACS prediction (AUC 0.725, 95% CI 0.724–0.727).ConclusionNon-obstructive lesions with higher ΔFFRCT or low-attenuation plaque showed a higher risk of ACS. The integration of anatomical, plaque, and hemodynamic characteristics can improve the noninvasive prediction of ACS risk in non-obstructive lesions.Key Points• Change in FFRCTacross the lesion (ΔFFRCT) was the most important predictor of ACS risk in non-obstructive lesions.• Non-obstructive lesions with higher ΔFFRCTor low-attenuation plaque were associated with a higher risk of ACS.• The integration of anatomical, plaque, and hemodynamic characteristics can improve the noninvasive prediction of ACS risk.

The presence of myocardial ischemia is the most important prognostic factor in patients with ischemic heart disease. Fractional flow reserve (FFR) is a gold standard invasive method used to detect the stenosis-specific myocardial ischemia. FFR-guided revascularization strategy is superior to angiography-guided strategy. The recently developed hyperemia-free index, instantaneous wave free ratio is being actively investigated. A non-invasive FFR derived from coronary CT angiography is now used in clinical practice. Due to rapid expansion of invasive and non-invasive physiologic assessment, comprehensive understanding of the role and potential pitfalls of each modality are required for its application. In this review, we focus on the basic and clinical aspects of physiologic assessment in ischemic heart disease.

Background: Association among local hemodynamic parameters and their implications in development of acute coronary syndrome (ACS) have not been fully investigated. Methods: A total of 216 lesions in ACS patients undergoing coronary CT angiography (CCTA) before 1–24 months from ACS event were analyzed. High-risk plaque on CCTA was defined as a plaque with ≥2 of low-attenuation plaque, positive remodeling, spotty calcification, and napkin-ring sign. With the use of computational fluid dynamics analysis, fractional flow reserve (FFR) derived from CCTA (FFR CT ) and local hemodynamic parameters including wall shear stress (WSS), axial plaque stress (APS), pressure gradient (PG) across the lesion, and delta FFR CT across the lesion (ΔFFR CT ) were obtained. The association among local hemodynamics and their discrimination ability for culprit lesions from non-culprit lesions were compared. Results: A total of 66 culprit lesions for later ACS and 150 non-culprit lesions were identified. WSS, APS, PG, and ΔFFR CT were strongly correlated with each other (all p < 0.001). This association was persistent in all lesion subtypes according to a vessel, lesion location, anatomical severity, high-risk plaque, or FFR CT ≤ 0.80. In discrimination of culprit lesions causing ACS from non-culprit lesions, WSS, PG, APS, and ΔFFR CT were independent predictors after adjustment for lesion characteristics, high-risk plaque, and FFR CT ≤ 0.80; and all local hemodynamic parameters significantly improved the predictive value for culprit lesions of high-risk plaque and FFR CT ≤ 0.80 (all p < 0.05). The risk prediction model for culprit lesions with FFR CT ≤ 0.80, high-risk plaque, and ΔFFR CT had a similar or superior discrimination ability to that with FFR CT ≤ 0.80, high-risk plaque, and WSS, APS, or PG; and the addition of WSS, APS, or PG into ΔFFR CT did not improve the model performance. Conclusions: Local hemodynamic indices were significantly intercorrelated, and all indices similarly provided additive and independent predictive values for ACS risk over high-risk plaque and impaired FFR CT .

BackgroundPositron emission tomography (PET)-derived LV MBF quantification is usually measured in standard anatomical vascular territories potentially averaging flow from normally perfused tissue with those from areas with abnormal flow supply. Previously we reported on an image-based tool to noninvasively measure absolute myocardial blood flow at locations just below individual epicardial vessel to help guide revascularization. The aim of this work is to determine the robustness of vessel-specific flow measurements (MBFvs) extracted from the fusion of dynamic PET (dPET) with coronary computed tomography angiography (CCTA) myocardial segmentations, using flow measured from the fusion with CCTA manual segmentation as the reference standard.MethodsForty-three patients’ 13NH3 dPET, CCTA image datasets were used to measure the agreement of the MBFvs profiles after the fusion of dPET data with three CCTA anatomical models: (1) a manual model, (2) a fully automated segmented model and (3) a corrected model, where major inaccuracies in the automated segmentation were briefly edited. Pairwise accuracy of the normality/abnormality agreement of flow values along differently extracted vessels was determined by comparing, on a point-by-point basis, each vessel’s flow to corresponding vessels’ normal limits using Dice coefficients (DC) as the metric.ResultsOf the 43 patients CCTA fully automated mask models, 27 patients’ borders required manual correction before dPET/CCTA image fusion, but this editing process was brief (2–3 min) allowing a 100% success rate of extracting MBFvs in clinically acceptable times. In total, 124 vessels were analyzed after dPET fusion with the manual and corrected CCTA mask models yielding 2225 stress and 2122 rest flow values. Forty-seven vessels were analyzed after fusion with the fully automatic masks producing 840 stress and 825 rest flow samples. All DC coefficients computed globally or by territory were ≥ 0.93. No statistical differences were found in the normal/abnormal flow classifications between manual and corrected or manual and fully automated CCTA masks.ConclusionFully automated and manually corrected myocardial CCTA segmentation provides anatomical masks in clinically acceptable times for vessel-specific myocardial blood flow measurements using dynamic PET/CCTA image fusion which are not significantly different in flow accuracy and within clinically acceptable processing times compared to fully manually segmented CCTA myocardial masks.

Objectives: We investigated the influence of coronary disease characteristics on prognostic implications of residual ischemia after coronary stent implantation. Methods: This study included 1,476 patients with drug-eluting stent implantation and available pre- and post-percutaneous coronary intervention (PCI) fractional flow reserve (FFR) measurements. Residual ischemia was defined as post-PCI FFR ≤ 0.80. Coronary disease characteristics with significant interaction hazard ratios (HRs) for clinical outcomes with residual ischemia were defined as interaction characteristics with residual ischemia (ICwRI). The primary outcome was target vessel failure (TVF)—a composite of cardiac death, target vessel myocardial infarction, and target vessel revascularization—at 2 years. Results: The mean pre- and post-PCI FFR were 0.68 ± 0.11 and 0.87 ± 0.07, respectively. During the median follow-up duration of 2.0 years, the cumulative incidence of TVF was 6.1%. The 203 vessels (13.8%) with residual ischemia had higher risks of TVF compared to that for post-PCI FFR >0.80 ( P < 0.001). ICwRI with a significant interaction HR with residual ischemia included pre-PCI SYNTAX score >17 and pre-PCI FFR ≤ 0.62. Each ICwRI had a direct prognostic effect not mediated by residual ischemia. The association between an increased TVF risk and residual ischemia was significant in patients with 0 or 1 ICwRI [hazard ratio (HR) 3.25, 95% confidence interval (CI) 1.90–5.57, P < 0.001] but not in those with 2 ICwRI (HR 0.47, 95% CI 0.14–1.64, P = 0.24). Among patients with post-PCI FFR >0.80, those with 2 ICwRI showed similar TVF risks to those with residual ischemia (HR 1.55, 95% CI 0.79–3.02, P = 0.20). Conclusions: Coronary disease characteristics including pre-PCI SYNTAX score and pre-PCI FFR affected the prognostic implications of residual ischemia. The prognostic relevance of residual ischemia was attenuated in patients with multiple interacting characteristics.