Risk prediction of inappropriate implantable cardioverter-defibrillator therapy using machine learning.

We aimed to develop machine learning-based predictive models for identifying inappropriate implantable cardioverter-defibrillator (ICD) therapy. Our study included 182 consecutive cases (average age 62.2 ± 4.5 years, 169 men) and employed 14 non-deep learning models for prediction (hold-out method). These models utilized selected electrocardiogram parameters and clinical features collected after ICD implantation. From the feature importance analysis of the best ML model, we established easily calculable scores. Among the patients, 25 (13.7%) experienced inappropriate therapy, and we identified 16 significant predictors. Using recursive feature elimination with cross-validation, we reduced the features to six with high feature importance: history of atrial arrhythmia (Atr-arrhythm), ischemic cardiomyopathy (ICM), absence of diabetes mellitus (DM), lack of cardiac resynchronization therapy (CRT), V3 ST level at J point (V3 STJ), and V5 R-wave amplitudes (V5R amp). The extra-trees classifier yielded the highest area under receiver operating characteristics curve (AUROC; 0.869 on test data). Thus, the Cardi35 score was defined as [+ 5.5*Atr-arrhythm - 1.5*CRT + 1.0*V3STJ + 1.0*V5R - 1.0*ICM - 0.5*DM], which demonstrated a hazard ratio of 1.62 (P < 0.001). A cut-off value of the score + 5.5 showed high AUROC (0.826). The ML approach can yield a robust prediction model, and the Cardi35 score was a convenient predictor for inappropriate therapy.

Predictors of In-Hospital Death in Patients With Acute Myocardial Infarction.

OBJECTIVE: Factors such as age, vital signs, renal function, Killip class, cardiac arrest, elevated cardiac biomarker levels, and ST deviation predict survival in patients with acute myocardial infarction (AMI). However, the existing risk assessment tools lack comprehensive consideration of catheter-related factors, and short-term prognostic predictors are unknown. This study aimed to clarify in-hospital prognostic predictors in hospitalized patients with AMI. METHODS: Five hundred and thirty-six patients who underwent percutaneous coronary intervention (PCI) for AMI were divided into non-survivor (n = 36) and survivor (n = 500) groups. Coronary risk factors, laboratory findings, angiographic findings, and clinical courses were compared between the two groups. Multiple logistic regression was used to analyze in-hospital death in pre- and post-PCI phases. RESULTS: In the pre-PCI phase, multiple logistic regression analysis revealed several predictors of in-hospital death, including systolic blood pressure [odds ratio (OR) = 0.985, p = 0.023)], Killip class ≥2 (OR = 14.051, p <0.001), and chronic kidney disease (OR = 4.859, p = 0.040). In the post-PCI phase, multiple logistic regression analysis revealed additional predictors of in-hospital death, including Killip class ≥2 (OR = 5.982, p = 0.039), presence of lesions in the left main trunk (OR = 51.381, p = 0.044), utilization of intra-aortic balloon pumps and percutaneous cardiopulmonary support (OR = 6.141, p = 0.016), and presence of multi-vessel disease (OR = 6.323, p = 0.022). CONCLUSION: Predictors of in-hospital death in AMI extend beyond conventional risk factors to include culprit lesions, mechanical support, and multi-vessel disease that manifest post-PCI.

Clinical Significance of Coronary Healed Plaques in Stable Angina Pectoris Patients Undergoing Percutaneous Coronary Intervention.

BACKGROUND: Coronary healed plaques (HPs) reportedly have high vulnerability or show advanced atherosclerosis and a risk of rapid plaque progression. However, the prognosis of stable angina pectoris (SAP) patients with HPs undergoing percutaneous coronary intervention (PCI) remains under-investigated.Methods and Results: We analyzed 417 consecutive lesions from SAP patients undergoing pre- and post-intervention optical coherence tomography (OCT) for which HPs were defined as having a layered appearance. We investigated the differences in clinical and lesion characteristics, and post-PCI outcomes between HPs and non-HPs. To account for differences in clinical characteristics, propensity score matching was performed between the groups. HPs were observed in 216 lesions (51.8%) in the total cohort. In the propensity-matched cohort (n=294), HPs had higher rates of angiographic-B2/C lesions (77.6% vs. 59.2%, P<0.001), OCT-lipid-rich plaques (40.8% vs. 25.9%, P=0.007), macrophages (78.2% vs. 44.2%, P<0.001), greater luminal area stenosis (73.5±11.0% vs. 71.5±10.3%, P=0.002), and a higher prevalence of post-stenting irregular tissue protrusion (45.1% vs. 14.7%, P<0.001) than non-HPs. In the total cohort, target lesion revascularization (TLR)-free survival was poorer for HPs (log-rank test 7.66; P=0.006), and Cox proportional hazards analysis showed HP as an independent predictor of TLR (hazard ratio, 5.98; 95% confidence interval, 1.72-20.82; P=0.005). CONCLUSIONS: In SAP patients, HPs had greater complexity of lesions and higher vulnerability, which may have contributed to the poorer post-PCI outcomes.

Optical coherence tomography and coronary angioscopy assessment of healed coronary plaque components.

PURPOSE: Histopathological or intracoronary image assessment of healed plaques (HPs) has been reported. However, the lesion characteristics of HPs remains undetermined yet. We assessed the healed plaque components in patients with coronary artery lesions using multiple imaging modalities. METHODS: We enrolled 33 stable angina pectoris (SAP) patients with 36 native coronary culprit lesions with angiography severe stenosis and without severe calcification undergoing pre-intervention optical coherence tomography (OCT) and coronary angioscopy (CAS). HPs were defined as layered phenotype on OCT. Lesion morphologies and plaque characteristics of HPs were assessed using OCT and CAS. RESULTS: HPs were observed in 19 lesions (52.8%). HP lesions had higher frequent B2/C lesions (89.4% vs. 52.9%, p = 0.02), worse pre-PCI coronary flow (corrected thrombolysis in myocardial infarction count 21.6 ± 13.5 vs. 13.8 ± 6.2, p = 0.047) and greater lumen-area stenosis (79.6 ± 10.6% vs. 68.0 ± 21.6%, p = 0.047) than non-HP lesions. HP lesions had higher prevalence of OCT-thin-cap fibroatheroma (TCFA) (31.6% vs. 0.0%, p = 0.02), OCT-macrophage (89.5% vs. 41.2%, p = 0.004), and CAS-red thrombus (89.5% vs. 41.2%, p = 0.004) than non-HP lesions. The combination of 3 features including OCT-TCFA, macrophages, and CAS-red thrombus showed higher predictive valuer for HPs on OCT than each single variable. Post-PCI irregular tissue protrusion was more frequently observed in lesions with HPs than in those without (52.6% vs. 13.3%, p = 0.03). CONCLUSIONS: SAP lesions with HPs might have more frequent vulnerable plaques with intraplaque inflammation and thrombus than those without, suggesting that layered phenotype on OCT might reflect not only healing process but also potential risks for future coronary events.

Eicosapentaenoic Acid combined with optimal statin therapy improves endothelial dysfunction in patients with coronary artery disease.

PURPOSE: Eicosapentaenoic acid (EPA) has been reported to augment endothelial function and improve clinical outcomes in patients with coronary artery disease (CAD). The purpose of this study was to determine whether EPA could improve residual endothelial dysfunction despite adequate lipid-lowering with statin in CAD patients. METHODS: Eighty patients with established CAD, who had been on statin treatment and had serum low-density lipoprotein cholesterol (LDL-C) levels <100 mg/dl, were randomly assigned to receive either 1,800 mg of EPA daily plus statin (EPA group, n = 40) or statin alone (Control group, n = 40). Lipid profiles and flow-mediated dilation (FMD) were assessed just before and after more than 3 months of treatment in both groups. Only patients who had impaired FMD (<6 %) before randomization were enrolled. RESULTS: After treatment for 5.2 ± 1.7 months, the EPA group showed a significant increase in the serum concentration of EPA and EPA to arachidonic acid (AA) (EPA/AA) ratio (62.5 ± 38.1 to 159.8 ± 53.8 µg/ml, 0.45 ± 0.34 to 1.20 ± 0.55, p < 0.01 for both). In the EPA group, serum triglycerides significantly decreased (150.7 ± 92.9 to 119.3 ± 60.7 mg/dl, p = 0.02), whereas no significant change was seen in the Control group. FMD, the primary study endpoint, showed a significant improvement in the EPA group (2.6 ± 1.6 % to 3.2 ± 1.6%, p = 0.02), whereas no significant change was observed in the Control group (2.7 ± 1.6% to 2.4 ± 1.7 %, p = 0.29). CONCLUSIONS: EPA improved endothelial function and impaired FMD in patients with established CAD who were on optimal statin therapy.

Longitudinal heterogeneity of coronary artery distensibility in plaques related to acute coronary syndrome.

BACKGROUND: How coronary distensibility contributes to stable or unstable clinical manifestations remains obscure. We postulated that the heterogeneous plaque distensibility is associated with unstable clinical presentations in patients with acute coronary syndrome (ACS). METHODS AND RESULTS: Seventeen and 19 ACS-related and -unrelated lesions, respectively, were visualized using intravascular ultrasound imaging with simultaneous intracoronary pressure recording. Systolic and diastolic lumen cross-sectional areas were measured at the lesion site and at five evenly spaced sites between the proximal and distal reference sites. The coronary distensibility index and stiffness index ß were calculated for each site and averaged for each coronary segment. Maximal distensibility index, standard deviation and the difference between maximal and minimal distensibility indices within each segment were significantly higher in the ACS-related than -unrelated plaques (5.6 ± 2.3 vs. 3.7 ± 1.8, p < 0.001, 2.1 ± 0.9 vs. 1.1 ± 0.6, p < 0.001 and 5.3 ± 2.3 vs. 2.8 ± 1.5, p < 0.001, respectively). Moreover, the difference in the distensibility index between the lesion site of ACS-related plaques and the immediate proximal site was significantly larger (2.88 ± 2.35 vs. 1.17 ± 1.44, p = 0.022) than that in ACS-unrelated plaques. CONCLUSIONS: Coronary artery distensibility is longitudinally more heterogeneous in ACS-related than-unrelated plaques, especially between the lesion and the immediate proximal site.