Reproducibility of an artificial intelligence optical coherence tomography software for tissue characterization: Implications for the design of longitudinal studies.

BACKGROUND: To assess the reproducibility of coronary tissue characterization by an Artificial Intelligence Optical Coherence Tomography software (OctPlus, Shanghai Pulse Medical Imaging Technology Inc.). METHODS: 74 patients presenting with multivessel ST-segment elevation myocardial infarction (STEMI) underwent optical coherence tomography (OCT) of the infarct-related artery at the end of primary percutaneous coronary intervention (PPCI) and during staged PCI (SPCI) within 7 days thereafter in the MATRIX (Minimizing Adverse Hemorrhagic Events by Transradial Access Site and angioX) Treatment-Duration study (ClinicalTrials.gov, NCT01433627). OCT films were run through the OctPlus software. The same region of interest between either side of the stent and the first branch was identified on OCT films for each patient at PPCI and SPCI, thus generating 94 pairs of segments. 42 pairs of segments were re-analyzed for intra-software difference. Five plaque characteristics including cholesterol crystal, fibrous tissue, calcium, lipid, and macrophage content were analyzed for various parameters (span angle, thickness, and area). RESULTS: There was no statistically significant inter-catheter (between PPCI and SPCI) or intra-software difference in the mean values of all the parameters. Inter-catheter correlation for area was best seen for calcification [intraclass correlation coefficient (ICC) 0.86], followed by fibrous tissue (ICC 0.87), lipid (ICC 0.62), and macrophage (ICC 0.43). Some of the inter-catheter relative differences for area measurements were large: calcification 9.75 %; cholesterol crystal 74.10 %; fibrous tissue 5.90 %; lipid 4.66 %; and macrophage 1.23 %. By the intra-software measurements, there was an excellent correlation (ICC > 0.9) for all tissue types. The relative differences for area measurements were: calcification 0.64 %; cholesterol crystal 5.34 %; fibrous tissue 0.19 %; lipid 1.07 %; and macrophage 0.60 %. Features of vulnerable plaque, minimum fibrous cap thickness and lipid area showed acceptable reproducibility. CONCLUSION: The present study demonstrates an overall good reproducibility of tissue characterization by the Artificial Intelligence Optical Coherence Tomography software. In future longitudinal studies, investigators may use discretion in selecting the imaging endpoints and sample size, accounting for the observed relative differences in this study.

The Ability of Near-Infrared Spectroscopy to Identify Vulnerable Patients and Plaques: A Systematic Review and Meta-Analysis.

Previous studies have analyzed the efficacy of near-infrared spectroscopy-derived lipid core burden index (LCBI) in quantifying and identifying high-risk plaques and patients at increased risk of future major adverse cardiac outcomes/major adverse cardiovascular and cerebrovascular events. A maxLCBI4mm of 400 or greater seems to be an effective threshold for classifying at-risk plaques. This meta-analysis provides a more precise odds ratio with a narrow standard deviation that can be used to guide future studies.

Comparison of Body Mass Index (Four Categories) to In-Hospital Outcomes in Patients Who Underwent Transcatheter Aortic Valve Implantation.

Although obesity is often associated with adverse outcomes in cardiovascular diseases, studies have demonstrated a beneficial effect on patients who underwent transcatheter aortic valve implantation (TAVI), coining the term "obesity paradox." We sought to determine if the obesity paradox is valid when patients are studied in body mass index (BMI) groups versus simplified classification of obese and nonobese. We examined the National Inpatient Sample database from 2016 to 2019 for all patients who underwent TAVI >18 years of age using the International Classification of Diseases, 10th edition procedure codes. Patients were grouped by BMI categories of underweight, overweight, obese, and morbidly obese. They were compared with normal-weight patients to assess the relative risk of in-hospital mortality, cardiogenic shock, ST-elevation myocardial infarction, bleeding complications requiring transfusions, and complete heart blocks requiring permanent pacemaker. A logistic regression model was constructed to account for potential confounders. Of the 221,000 patients who underwent TAVI, 42,315 patients with appropriate BMI designation were stratified into BMI groups. Compared to the normal-weight group, overweight, obese, and morbid-obese TAVI patients were associated with a lower risk of in-hospital mortality (relative risk [RR] 0.48, confidence interval [CI] 0.29 to 0.77, p <0.001), (RR 0.42, CI 0.28 to 0.63, p <0.001), (RR 0.49, CI 0.33 to 0.71, p <0.001 respectively), cardiogenic shock (RR 0.27, CI 0.20 to 0.38, p <0.001), (RR 0.21, CI 0.16 to 0.27, p <0.001), (RR 0.21, CI 0.16 to 0.26, p <0.001), and blood transfusions (RR 0.63, CI 0.50 to 0.79, p <0.001), (RR 0.47, CI 0.39 to 0.58, p <0.001), (RR 0.61, CI 0.51 to 0.74, p <0.001). This study indicated that obese patients were at a significantly lower risk of in-hospital mortality, cardiogenic shock, and bleeding complications requiring transfusions. In conclusion, our study supported the existence of the obesity paradox in TAVI patients.

Multivessel vs. culprit-vessel only percutaneous coronary interventions in acute myocardial infarction and cardiogenic shock: a systematic review and meta-analysis of prospective randomized and retrospective studies.

AIMS: Studies comparing outcomes of multivessel (MV) vs. culprit-vessel (CV) only percutaneous coronary intervention (PCI) during index cardiac catheterization in patients presenting with acute myocardial infarction (MI) and cardiogenic shock (CS) have reported conflicting results. In this systematic review we aim to investigate outcomes with MV vs. CV-only revascularization strategies in patients with acute MI and CS. METHODS AND RESULTS: PubMed, Google Scholar, CINAHL and Cochrane databases were queried for studies comparing MV vs. CV PCI in patients with acute MI and CS. Data were extracted and pooled by means of random effects model. Primary outcome was early all-cause mortality (up to 30 days), while the secondary outcomes included late all-cause mortality (mean, 11.4 months), stroke, new renal replacement therapy, reinfarction, repeat revascularization, and bleeding. Pooled odds ratio (OR), 95% confidence intervals (CIs), and number needed to harm (NNH) were calculated. A total of 16 studies enrolling 75 431 patients were included. The MV PCI was associated with higher risk of early mortality [OR 1.17, 95% CI (1.00-1.35); P = 0.04; NNH = 62], stroke [1.15 (1.03-1.29); P = 0.01; NNH = 351], and new renal replacement therapy [1.33 (1.06-1.67); P = 0.01; NNH = 61]; and with lower risk of repeat revascularization [0.61 (0.41-0.89); P = 0.01] when compared with CV PCI. No significant difference was observed in late-term mortality [1.02 (0.84-1.25); P = 0.84], risk of reinfarction [1.13 (0.94-1.35); P = 0.18], or bleeding [1.21 (0.94-1.55); P = 0.13] between groups. CONCLUSION: Among patients with acute MI and CS, MV PCI during index cardiac catheterization was associated with higher risk of early mortality, stroke, and renal replacement therapy.