Fully automated quantitative coronary angiography versus optical coherence tomography guidance for coronary stent implantation (FLASH): Study protocol for a randomized controlled noninferiority trial.

BACKGROUND: Artificial intelligence-based quantitative coronary angiography (AI-QCA) has been developed to provide a more objective and reproducible data about the severity of coronary artery stenosis and the dimensions of the vessel for intervention in real-time, overcoming the limitations of significant inter- and intraobserver variability, and time-consuming nature of on-site QCA, without requiring extra time and effort. Compared with the subjective nature of visually estimated conventional CAG guidance, AI-QCA guidance provides a more practical and standardized angiography-based approach. Although the advantage of intravascular imaging-guided PCI is increasingly recognized, their broader adoption is limited by clinical and economic barriers in many catheterization laboratories. METHODS: The FLASH (fully automated quantitative coronary angiography versus optical coherence tomography guidance for coronary stent implantation) trial is a randomized, investigator-initiated, multicenter, open-label, noninferiority trial comparing the AI-QCA-assisted PCI strategy with optical coherence tomography-guided PCI strategy in patients with significant coronary artery disease. All operators will utilize a novel, standardized AI-QCA software and PCI protocol in the AI-QCA-assisted group. A total of 400 patients will be randomized to either group at a 1:1 ratio. The primary endpoint is the minimal stent area (mm2), determined by the final OCT run after completion of PCI. Clinical follow-up and cost-effectiveness evaluations are planned at 1 month and 6 months for all patients enrolled in the study. RESULTS: Enrollment of a total of 400 patients from the 13 participating centers in South Korea will be completed in February 2024. Follow-up of the last enrolled patients will be completed in August 2024, and primary results will be available by late 2024. CONCLUSION: The FLASH is the first clinical trial to evaluate the feasibility of AI-QCA-assisted PCI, and will provide the clinical evidence on AI-QCA assistance in the field of coronary intervention. CLINICAL TRIAL REGISTRATION: URL: https://www. CLINICALTRIALS: gov. Unique identifier: NCT05388357.

Nutritional status and risk of all-cause mortality in patients undergoing transcatheter aortic valve replacement assessment using the geriatric nutritional risk index and the controlling nutritional status score.

BACKGROUND: Nutritional status, a key marker of patient frailty, is an important prognostic factor after transcatheter aortic valve replacement (TAVR). Few investigations have evaluated the clinical usefulness of nutritional assessment tools for predicting the risk of mortality following TAVR. METHODS: A total of 412 patients with symptomatic severe AS who underwent TAVR between March 2010 and August 2017 were stratified into subgroups by their Geriatric Nutritional Risk Index [GNRI, low ≤ 98 vs. high > 98 (better nutritional status)] and Controlling Nutritional Status (CONUT) score [low ≤ 3 vs. high ≥ 4; (poorer nutritional status)]. The primary study outcome was all-cause mortality at 1 year. RESULTS: Patients with low GNRI score showed a significantly higher 1-year mortality rate as compared to those with high GNRI score (13.0% vs. 3.2%, respectively; P = 0.001). Similarly, patients with high CONUT score had a significantly higher rate of 1-year mortality than those with low CONUT score (15.7% vs. 6.2%, respectively; P = 0.005). However, in multivariable Cox proportional-hazards models, low GNRI was the only independent predictor of mortality (adjusted hazard ratio, 3.77; 95% confidence interval 1.54-9.20; P = 0.004). Overall, integration of GNRI into conventional risk models of STS score or logistic EuroSCORE resulted in improved predictive value for mortality measured by the net reclassification improvement and the integrated discrimination improvement. CONCLUSIONS: In patients undergoing TAVR, low GNRI (but not high CONUT score) was independently associated with a higher risk of 1-year mortality. Further research is required to determine whether nutritional screening and management can improve clinical outcomes in patients undergoing TAVR.

Incidence, Predictors, Management, and Clinical Significance of New-Onset Atrial Fibrillation After Transcatheter Aortic Valve Implantation.

There is limited information on the incidence, management, and prognostic impact of new-onset atrial fibrillation (NOAF) following transcatheter aortic valve implantation (TAVI) for severe aortic valve stenosis. In the prospective ASAN-TAVI registry, we evaluated a total of 347 consecutive patients who underwent TAVI from March 2010 to August 2017. The primary end point was a composite of stroke or systemic embolism at 12 months. The study subjects were categorized into 3 groups; pre-existing AF (50 patients), NOAF (31 patients), and non-AF (266 patients) group. NOAF developed in 10.4% of patients without pre-existing AF after TAVI and most cases were paroxysmal type (93.6%). Pharmacologic and electrical cardioversion were tried in 13 (41.9%) and 6 (19.4%) patients and success rates were 61.5% and 33.3%, respectively. NOAF-associated case rate for primary end point was 22.6%. Transfemoral access and cardiac tamponade were independent predictors of NOAF. Patients with NOAF, as compared with those with pre-existing AF and those without AF, had an increased 1-year rate of primary end point (24.0% vs 9.9% vs 7.2%, respectively; p <0.001). By multivariable analysis, NOAF was an independent predictor of 1-year rate of primary end point (adjusted hazard ratio: 3.31; 95% CI: 1.34 to 8.20; p = 0.010). In conclusion, patients with severe aortic valve stenosis who underwent TAVI, NOAF occurred in 10% and 1 of 4 NOAF patients experienced stroke or systemic embolization. The presence of NOAF was associated with a substantially higher risk of stroke or systemic embolization.

Machine learning assessment of myocardial ischemia using angiography: Development and retrospective validation.

BACKGROUND: Invasive fractional flow reserve (FFR) is a standard tool for identifying ischemia-producing coronary stenosis. However, in clinical practice, over 70% of treatment decisions still rely on visual estimation of angiographic stenosis, which has limited accuracy (about 60%-65%) for the prediction of FFR < 0.80. One of the reasons for the visual-functional mismatch is that myocardial ischemia can be affected by the supplied myocardial size, which is not always evident by coronary angiography. The aims of this study were to develop an angiography-based machine learning (ML) algorithm for predicting the supplied myocardial volume for a stenosis, as measured using coronary computed tomography angiography (CCTA), and then to build an angiography-based classifier for the lesions with an FFR < 0.80 versus ≥ 0.80. METHODS AND FINDINGS: A retrospective study was conducted using data from 1,132 stable and unstable angina patients with 1,132 intermediate lesions who underwent invasive coronary angiography, FFR, and CCTA at the Asan Medical Center, Seoul, Korea, between 1 May 2012 and 30 November 2015. The mean age was 63 ± 10 years, 76% were men, and 72% of the patients presented with stable angina. Of these, 932 patients (assessed before 31 January 2015) constituted the training set for the algorithm, and 200 patients (assessed after 1 February 2015) served as a test cohort to validate its diagnostic performance. Additionally, external validation with 79 patients from two centers (CHA University, Seongnam, Korea, and Ajou University, Suwon, Korea) was conducted. After automatic contour calibration using the caliber of guiding catheter, quantitative coronary angiography was performed using the edge-detection algorithms (CAAS-5, Pie-Medical). Clinical information was provided by the Asan BiomedicaL Research Environment (ABLE) system. The CCTA-based myocardial segmentation (CAMS)-derived myocardial volume supplied by each vessel (right coronary artery [RCA], left anterior descending [LAD], left circumflex [LCX]) and the myocardial volume subtended to a stenotic segment (CAMS-%Vsub) were measured for labeling. The ML for (1) predicting vessel territories (CAMS-%LAD, CAMS-%LCX, and CAMS-%RCA) and CAMS-%Vsub and (2) identifying the lesions with an FFR < 0.80 was constructed. Angiography-based ML, employing a light gradient boosting machine (GBM), showed mean absolute errors (MAEs) of 5.42%, 8.57%, and 4.54% for predicting CAMS-%LAD, CAMS-%LCX, and CAMS-%RCA, respectively. The percent myocardial volumes predicted by ML were used to predict the CAMS-%Vsub. With 5-fold cross validation, the MAEs between ML-predicted percent myocardial volume subtended to a stenotic segment (ML-%Vsub) and CAMS-%Vsub were minimized by the elastic net (6.26% ± 0.55% for LAD, 5.79% ± 0.68% for LCX, and 2.95% ± 0.14% for RCA lesions). Using all attributes (age, sex, involved vessel segment, and angiographic features affecting the myocardial territory and stenosis degree), the ML classifiers (L2 penalized logistic regression, support vector machine, and random forest) predicted an FFR < 0.80 with an accuracy of approximately 80% (area under the curve [AUC] = 0.84-0.87, 95% confidence intervals 0.71-0.94) in the test set, which was greater than that of diameter stenosis (DS) > 53% (66%, AUC = 0.71, 95% confidence intervals 0.65-0.78). The external validation showed 84% accuracy (AUC = 0.89, 95% confidence intervals 0.83-0.95). The retrospective design, single ethnicity, and the lack of clinical outcomes may limit this prediction model's generalized application. CONCLUSION: We found that angiography-based ML is useful to predict subtended myocardial territories and ischemia-producing lesions by mitigating the visual-functional mismatch between angiographic and FFR. Assessment of clinical utility requires further validation in a large, prospective cohort study.

Stent Thrombosis With Drug-Eluting Stents and Bioresorbable Scaffolds: Evidence From a Network Meta-Analysis of 147 Trials.

OBJECTIVES: This study sought to perform a systematic review and network meta-analysis to compare the relative safety and efficacy of contemporary DES and BVS. BACKGROUND: To improve outcomes of patients undergoing percutaneous coronary revascularization, there have been advances in the design of drug-eluting stents (DES), including the development of drug-eluting bioresorbable vascular scaffolds (BVS). METHODS: Prospective, randomized, controlled trials comparing bare-metal stents (BMS), paclitaxel-eluting stents (PES), sirolimus-eluting stents (SES), Endeavor zotarolimus-eluting stents (E-ZES), cobalt-chromium (CoCr) everolimus-eluting stents (EES), platinum-chromium (PtCr)-EES, biodegradable polymer (BP)-EES, Resolute zotarolimus-eluting stents (R-ZES), BP biolimus-eluting stents (BP-BES), hybrid sirolimus-eluting stents (H [Orsiro]-SES), polymer-free sirolimus- and probucol-eluting stents, or BVS were searched in online databases. The primary endpoint was definite or probable stent thrombosis at 1 year. RESULTS: A total of 147 trials including 126,526 patients were analyzed in this study. All contemporary DES were superior to BMS and PES in terms of definite or probable stent thrombosis at 1 year. CoCr-EES, PtCr-EES, and H-SES were associated with significantly lower risk than BVS. CoCr-EES and H-SES were superior to SES and BP-BES. The risk of myocardial infarction was significantly lower with H-SES than with BVS. There were no significant differences regarding all-cause or cardiac mortality. Contemporary devices including BVS showed comparably low risks of repeat revascularization. CONCLUSIONS: Contemporary DES, including biocompatible DP-DES, BP-DES, and polymer-free DES, showed a low risk of definite or probable stent thrombosis at 1 year. BVS had an increased risk of device thrombosis compared with CoCr-EES, PtCr-EES, and H-SES. Data from extended follow-up are warranted to confirm the long-term safety of contemporary coronary devices.

Importance of clinical and echocardiographic hemodynamic assessment in chronic pulmonary embolism.

We describe a 42-year-old man presenting to the emergency department with cardiogenic shock. He had a prior history of acute pulmonary embolism (PE), and had been on anticoagulation for 2 years. Although computed tomographic pulmonary angiography performed at the emergency department showed no change in the extent of PE and did not support a role of surgical treatment, pulmonary embolectomy was recommended by attending physician based on clinical and echocardiographic hemodynamic findings like unstable vital sign and markedly enlarged right ventricle with severely depressed systolic function. Surgery confirmed the presence of fresh thrombi. After surgery, hemodynamic status was progressively improved, but the patient died due to pneumonia and pulmonary hemorrhage.