Background Volumetric intravascular ultrasound (IVUS) analysis is currently performed at a fixed frame interval, neglecting the cyclic changes in vessel dimensions occurring during the cardiac... Show moreBackground Volumetric intravascular ultrasound (IVUS) analysis is currently performed at a fixed frame interval, neglecting the cyclic changes in vessel dimensions occurring during the cardiac cycle that can affect the reproducibility of the results. Analysis of end-diastolic (ED) IVUS frames has been proposed to overcome this limitation. However, at present, there is lack of data to support its superiority over conventional IVUS. Objectives The present study aims to compare the reproducibility of IVUS volumetric analysis performed at a fixed frame interval and at the ED frames, identified retrospectively using a novel deep-learning methodology. Methods IVUS data acquired from 97 vessels were included in the present study; each vessel was segmented at 1 mm interval (conventional approach) and at ED frame twice by an expert analyst. Reproducibility was tested for the following metrics; normalized lumen, vessel and total atheroma volume (TAV), and percent atheroma volume (PAV). Results The mean length of the analyzed segments was 50.0 +/- 24.1 mm. ED analysis was more reproducible than the conventional analysis for the normalized lumen (mean difference: 0.76 +/- 4.03 mm(3) vs. 1.72 +/- 11.37 mm(3); p for the variance of differences ratio < 0.001), vessel (0.30 +/- 1.79 mm(3) vs. -0.47 +/- 10.26 mm(3); p < 0.001), TAV (-0.46 +/- 4.03 mm(3) vs. -2.19 +/- 14.39 mm(3); p < 0.001) and PAV (-0.12 +/- 0.59% vs. -0.34 +/- 1.34%; p < 0.001). Results were similar when the analysis focused on the 10 mm most diseased segment. The superiority of the ED approach was due to a more reproducible detection of the segment of interest and to the fact that it was not susceptible to the longitudinal motion of the IVUS probe and the cyclic changes in vessel dimensions during the cardiac cycle. Conclusions ED IVUS segmentation enables more reproducible volumetric analysis and quantification of TAV and PAV that are established end points in longitudinal studies assessing the efficacy of novel pharmacotherapies. Therefore, it should be preferred over conventional IVUS analysis as its higher reproducibility is expected to have an impact on the sample size calculation for the primary end point. Show less
Aims We aimed to update the logistic clinical SYNTAX score to predict 2 year all-cause mortality after contemporary percutaneous coronary intervention (PCI).Methods and results We analyzed 15,883... Show moreAims We aimed to update the logistic clinical SYNTAX score to predict 2 year all-cause mortality after contemporary percutaneous coronary intervention (PCI).Methods and results We analyzed 15,883 patients in the GLOBAL LEADERS study who underwent PCI. The logistic clinical SYNTAX model was updated after imputing missing values by refitting the original model (refitted original model) and fitting an extended new model (new model, with, selection based on the Akaike Information Criterion). External validation was performed in 10,100 patients having PCI at Fu Wai hospital.Chronic obstructive pulmonary disease, prior stroke, current smoker, hemoglobin level, and white blood cell count were identified as additional independent predictors of 2 year all-cause mortality and included into the new model.The c-indexes of the original, refitted original and the new model in the derivation cohort were 0.74 (95% CI 0.72-0.76), 0.75 (95% CI 0.73-0.77), and 0.78 (95% CI 0.76-0.80), respectively. The c-index of the new model was lower in the validation cohort than in the derivation cohort, but still showed improved discriminative ability of the newly developed model (0.72; 95% CI 0.67-0.77) compared to the refitted original model (0.69; 95% CI 0.64-0.74). The models overestimated the observed 2 year all-cause mortality of 1.11% in the Chinese external validation cohort by 0.54 percentage points, indicating the need for calibration of the model to the Chinese patient population.Conclusions The new model of the logistic clinical SYNTAX score better predicts 2 year all-cause mortality after PCI than the original model. The new model could guide clinical decision making by risk stratifying patients undergoing PCI. Show less
Objectives We sought to assess the clinical value of adding intravascular ultrasound (IVUS) evaluation to coronary angiography (CA) to guide extrinsic left main coronary artery (LMCA) compression... Show moreObjectives We sought to assess the clinical value of adding intravascular ultrasound (IVUS) evaluation to coronary angiography (CA) to guide extrinsic left main coronary artery (LMCA) compression diagnosis and treatment in pulmonary hypertension (PH). Background LMCA compression due to a pulmonary artery aneurysm (PAA) is a severe complication of PH. Although guidelines encourage the use of IVUS for LMCA disease evaluation, it has hardly been used in this scenario. Methods We analyzed morbimortality of type 1 and 4 PH patients with clinically suspected LMCA compression by a PAA between 2010 and 2018 in a reference unit. LMCA compression was prospectively assessed with CA +/- IVUS. Angiographic-LMCA compression was considered conclusive when LMCA stenosis>50% was present in four predetermined projections; inconclusive, when LMCA stenosis>50% was present in 50% was present. Patients with conclusive and inconclusive CA underwent IVUS. IVUS-LMCA compression was defined as systolic minimum lumen area < 6 mm(2). Results LMCA compression was suspected in 23/796 patients (3%). CA was conclusive for compression in 7(30.5%), inconclusive in 9(39%), and negative in 7(30.5%). IVUS confirmed LMCA compression in 6/7(86%) patients with conclusive CA and in 2/9(22%) with inconclusive CA. Patients fulfilling IVUS criteria for LMCA compression underwent stent implantation. At 20 months follow-up a composite end-point of death, stent restenosis/thrombosis, or lung transplant was reported in three patients (13%). Conclusions CA can misdiagnose LMCA extrinsic compression. IVUS discriminates better whether significant compression by a PAA exists or not, avoiding unnecessary LMCA stenting. Patients treated following this strategy show a low rate of major clinical events at 20 months follow-up. Show less
Objectives To evaluate the frequency of procedural-related atrial branch occlusion in ST-segment elevation myocardial infarction (STEMI) patients and its association with atrial arrhythmias at 1... Show moreObjectives To evaluate the frequency of procedural-related atrial branch occlusion in ST-segment elevation myocardial infarction (STEMI) patients and its association with atrial arrhythmias at 1-year follow-up.Background Atrial ischemia due to procedural-related coronary atrial branch occlusion in elective percutaneous coronary intervention (PCI) has been associated with atrial arrhythmias. Its role in a STEMI scenario is unknown.Methods STEMI patients treated with primary PCI were classified according to the loss or patency of an atrial branch at the end of the procedure. The occurrence of atrial arrhythmias was documented on 24-hr Holter-ECG at 3 and 6 months or on ECG during 1-year follow-up visits.Results Of 900 patients, 355 (age 61 +/- 12 years, 79% male) underwent primary PCI involving the origin of an atrial branch. Procedural-related coronary atrial branch occlusion was observed in 18 (5%) individuals). During 1-year follow-up, 33% of patients with procedural-related atrial branch occlusion presented atrial arrhythmias, as compared with 55% in those with a patent atrial branch (p = .088). Age, no previous history of myocardial infarction, and a reduced flow in the culprit vessel were the only independent correlates of atrial arrhythmias.Conclusions The frequency of procedural-related atrial branch occlusion during primary PCI is low (5%) and is not associated with increased frequency of atrial arrhythmias at 1-year follow-up. Show less
Pyxaras, S.A.; Toth, G.G.; Gioia, G. di; Ughi, G.J.; Tu, S.X.; Rusinaru, D.; ... ; Wijns, W. 2017
Background: Three-dimensional (3D) quantitative coronary angiography (QCA) requires two angiographic views to restore vessel dimensions. This study investigated the impact of acquisition angle... Show moreBackground: Three-dimensional (3D) quantitative coronary angiography (QCA) requires two angiographic views to restore vessel dimensions. This study investigated the impact of acquisition angle differences (AADs) of the two angiographic views on the assessed dimensions by 3D QCA. Methods: X-ray angiograms of an assembled brass phantom with different types of straight lesions were recorded at multiple angiographic projections. The projections were randomly matched as pairs and 3D QCA was performed in those pairs with AAD larger than 25 degrees. The lesion length and diameter stenosis in three different lesions, a circular concentric severe lesion (A), a circular concentric moderate lesion (B), and a circular eccentric moderate lesion (C), were measured by 3D QCA. The acquisition protocol was repeated for a silicone bifurcation phantom, and the bifurcation angles and bifurcation core volume were measured by 3D QCA. The measurements were compared with the true dimensions if applicable and their correlation with AAD was studied. Results: 50 matched pairs of angiographic views were analyzed for the brass phantom. The average value of AAD was 48.0 +/- 14.1 degrees. The percent diameter stenosis was slightly overestimated by 3D QCA for all lesions: A (error 1.2 +/- 0.9%, P < 0.001); B (error 0.6 +/- 0.5%, P < 0.001); C (error 1.1 +/- 0.6%, P < 0.001). The correlation of the measurements with AAD was only significant for lesion A (R-2 = 0.151, P = 0.005). The lesion length was slightly overestimated by 3D QCA for lesion A (error 0.06 +/- 0.18 mm, P = 0.026), but well assessed for lesion B (error -0.00 +/- 0.16 mm, P = 0.950) and lesion C (error -0.01 +/- 0.18 mm, P = 0.585). The correlation of the measurements with AAD was not significant for any lesion. Forty matched pairs of angiographic views were analyzed for the bifurcation phantom. The average value of AAD was 49.1 +/- 15.4 degrees. 3D QCA slightly overestimated the proximal angle (error 0.4 +/- 1.1 degrees, P = 0.046) and the distal angle (error 1.5 +/- 1.3 degrees, P < 0.001). The correlation with AAD was only significant for the distal angle (R-2 = 0.256, P = 0.001). The correlation of bifurcation core volume measurements with AAD was not significant (P = 0.750). Of the two aforementioned measurements with significant correlation with AAD, the errors tended to increase as AAD became larger. Conclusions: 3D QCA can be used to reliably assess vessel dimensions and bifurcation angles. Increasing the AAD of the two angiographic views does not increase accuracy and precision of 3D QCA for circular lesions or bifurcation dimensions. (C) 2011 Wiley-Liss, Inc. Show less
Background: Accurate on-line assessments of vessel dimensions are of utmost importance for selecting the appropriate stent size in coronary interventions. Recently a new three-dimensional... Show moreBackground: Accurate on-line assessments of vessel dimensions are of utmost importance for selecting the appropriate stent size in coronary interventions. Recently a new three-dimensional quantitative coronary angiography (3D QCA) analytical software package was developed to accurately assess the vessel dimensions for the planning and guidance of such coronary interventions. This study aimed to validate the 3D QCA software package for assessing arterial segment length by comparing with intravascular ultrasound (IVUS). In addition, the difference in the two measurements from 3D QCA and IVUS for curved segments was studied. Methods: A retrospective study including 20 patients undergoing both coronary angiography and IVUS examinations of the left coronary artery was set up for the validation. The same vessel segments of interest between proximal and distal markers were identified and measured on both angiographic and IVUS images, by the 3D QCA software and by a quantitative IVUS software package, respectively. In addition, the curvature of each of the segments of interest was assessed and the correlation between the accumulated curvature of the segment and the difference in segment lengths measured from the two imaging modalities was analyzed. Results: 37 vessel segments of interest were identified from both angiographic and IVUS images. The 3D QCA segment length was slightly longer than the IVUS segment length (15.42 +/- 6.02 mm vs. 15.12 +/- 5.81 mm, P = 0.040). The linear correlation of the two measurements was: 3D QCA Length = -0.09 + 1.03 x IVUS Length (r(2) = 0.98, P < 0.001). Bland-Altman plot showed that the difference in the two measurements was not correlated with the average of the two measurements (P = 0.141), but with the accumulated curvature of the segment (P = 0.015). After refining the difference by the correlation, the average difference of the two measurements decreased from 0.30 +/- 0.86 mm (P = 0.040) to 0.00 +/- 0.78 mm (P = 0.977). Conclusions: The 3D QCA software package can accurately assess the actual arterial segment length. The difference in segment lengths measured from 3D CICA and IVUS was correlated with the accumulated curvature of the segment. (C) 2010 Wiley-Liss, Inc. Show less
