Right Ventricular Longitudinal Strain Predicts Low-Cardiac- Output Syndrome After Surgical Aortic Valve Replacement in Patients With Preserved and Mid-range Ejection Fraction.

OBJECTIVES: The aim of this study was to analyze whether right ventricular free wall longitudinal strain (RVFWSL) could be a predictor of low-cardiac-output syndrome (LCOS) after surgical aortic valve replacement (SAVR) in patients with left ventricular ejection fraction ≥40%. DESIGN: Prospective, observational study. SETTING: The study was conducted at a third level university hospital. PARTICIPANTS: The study comprised 75 patients with severe aortic stenosis and LVEF ≥40% who underwent SAVR. The primary outcome was the occurrence of LCOS, and secondary outcomes were in-hospital mortality, hospital stay, or vasoplegic syndrome. INTERVENTIONS: Patients were divided into two groups (LCOS and no LCOS), and RVFWSL was analyzed to determine whether it is a predictor for LCOS. In addition, a receiver operating characteristic curve also was constructed, and the best cutoff value to predict LCOS was found. Furthermore, the reproducibility of RVFWSL measurements was evaluated. MEASUREMENT AND MAIN RESULTS: The incidence of LCOS was 20% in the present study's cohort. After multivariate analysis, cross-clamp time (odds ratio 1.06, 95% confidence interval 1.02-1.11; p = 0.002) and RVFWSL (odds ratio 1.41, 95% confidence interval 1.07-1.87; p = 0.015) were the only predictors of LCOS. However, RVFWSL did not show association with secondary outcomes (p > 0.05 for all). The area under the curve of RVFWSL to predict LCOS was 0.75, and the best cutoff value was -17.3%, with a sensitivity of 86.7% and specificity of 61.7%. CONCLUSIONS: RVFWSL seems to be a predictor of LCOS in patients with severe aortic stenosis and LVEF ≥40% undergoing SAVR. RVFWSL less than -17.3% may identify patients at increased risk for LCOS.

Integrating the STOP-BANG Score and Clinical Data to Predict Cardiovascular Events After Infarction: A Machine Learning Study.

BACKGROUND: OSA conveys worse clinical outcomes in patients with coronary artery disease. The STOP-BANG score is a simple tool that evaluates the risk of OSA and can be added to the large number of clinical variables and scores that are obtained during the management of patients with myocardial infarction (MI). Currently, machine learning (ML) is able to select and integrate numerous variables to optimize prediction tasks. RESEARCH QUESTION: Can the integration of STOP-BANG score with clinical data and scores through ML better identify patients who experienced an in-hospital cardiovascular event after acute MI? STUDY DESIGN AND METHODS: This is a prospective observational cohort study of 124 patients with acute MI of whom the STOP-BANG score classified 34 as low (27.4%), 30 as intermediate (24.2%), and 60 as high (48.4%) OSA-risk patients who were followed during hospitalization. ML implemented feature selection and integration across 47 variables (including STOP-BANG score, Killip class, GRACE score, and left ventricular ejection fraction) to identify those patients who experienced an in-hospital cardiovascular event (ie, death, ventricular arrhythmias, atrial fibrillation, recurrent angina, reinfarction, stroke, worsening heart failure, or cardiogenic shock) after definitive MI treatment. Receiver operating characteristic curves were used to compare ML performance against STOP-BANG score, Killip class, GRACE score, and left ventricular ejection fraction, independently. RESULTS: There were an increasing proportion of cardiovascular events across the low, intermediate, and high OSA risk groups (P = .005). ML selected 7 accessible variables (ie, Killip class, leukocytes, GRACE score, c reactive protein, oxygen saturation, STOP-BANG score, and N-terminal prohormone of B-type natriuretic peptide); their integration outperformed all comparators (area under the curve, 0.83 [95% CI, 0.74-0.90]; P < .01). INTERPRETATION: The integration of the STOP-BANG score into clinical evaluation (considering Killip class, GRACE score, and simple laboratory values) of subjects who were admitted for an acute MI because of ML can significantly optimize the identification of patients who will experience an in-hospital cardiovascular event.

Abnormal myocardial perfusion and risk of heart failure in patients with type 2 diabetes mellitus.

BACKGROUND: Diabetes is a major risk factor for heart failure (HF), although the pathophysiological processes have not been clarified. OBJECTIVE: To determine the prevalence of HF and of abnormal myocardial perfusion in diabetic patients evaluated using technetium (99m) sestamibi single-photon emission computed tomography. METHODS: An observational cross-sectional study was conducted that included patients with type 2 diabetes mellitus who underwent echocardiography to diagnose HF and a pharmacological stress test with intravenous dipyridamole to examine cardiac scintigraphic perfusion abnormalities. Clinical and biochemical data were also collected. RESULTS: Of the 160 diabetic patients included, 92 (57.6%) were in HF and 68 (42.5%) were not. When patients were stratified according to the presence of abnormal myocardial perfusion, those with abnormal perfusion had a higher prevalence of HF (93%) than those with normal perfusion (44.4%) (P<0.0001). Patients with HF weighed more (P=0.03), used insulin less frequently (P=0.01), had lower total cholesterol (P=0.05) and high-density lipoprotein cholesterol concentrations (P=0.002), and a greater number of their myocardial segments showed abnormal perfusion (P≤0.001). More HF patients had a history of myocardial infarction (P<0.001) compared with those without HF. In a logistic regression analysis, the number of segments exhibiting abnormal myocardial perfusion was an independent risk factor for HF. CONCLUSIONS: The prevalence of HF in diabetic patients was high and HF predominantly occured in association with myocardial ischemia.

Effect of ivabradine on endothelial function in diastolic and right heart failure patients.

Background. Ivabradine is an If ion current inhibitor that has proved to reduce mortality in patients with systolic heart failure by slowing heart rate without decreasing myocardial contractility. Photoplethysmography is a simple, low-cost optical technique that can evaluate vascular function and detect changes in blood flow, pulse, and swelling of tissular microvascular space. Objective. To evaluate the effect of ivabradine on endothelial function by photoplethysmography in diastolic and right heart failure patients. Methodology. 15 patients were included (mean age of 78.1 ± 9.2 years) with optimally treated diastolic and right heart failure. They underwent photoplethysmography before and after induced ischemia to evaluate the wave blood flow on the finger, using the maximum amplitude time/total time (MAT/TT) index. Two measurements were made before and after oral Ivabradine (mean 12.5 mg a day during 6 months of followup). Results. In the study group, the MAT/TT index was 29.1 ± 2.2 versus 24.3 ± 3.2 (P = 0.05) in basal recording and 30.4 ± 2.1 versus 23.3 ± 2.9 (P = 0.002), before versus after ischemia and before versus after Ivabradine intervention, respectively. Conclusions. Ivabradine administration improves endothelial function (shear stress) in diastolic and right heart failure patients.

Improvement of ventricular function in systolic heart failure patients with oral L-citrulline supplementation.

BACKGROUND: The utility of L-arginine and L-citrulline in treatment of arterial hypertension by increasing vascular oxide nitric availability has been demonstrated. Photoplethysmography, a simple and low-cost optical technique, makes it possible to assess vascular function and to detect changes in blood flow, pulse and swelling of the microvascular tissular space. The aim of the study was to evaluate the effect of L-citrulline supplementation on functional class, ejection fraction and peripheral blood flow in patients with systolic heart failure. METHODS: Thirty-five stable outpatients attending the Heart Failure Clinic at the INCMNSZ underwent clinical evaluation, radioisotopic ventriculography and photoplethysmography before and at the end of 4 months. They were randomized into two groups: experimental group, with oral L-citrulline supplementation (3 g/day, n = 20) and control group, without supplementation (n = 15). RESULTS: In the experimental group the left ventricular ejection fraction (LVEF) increased 20.3% at rest and 12.7% with stress, as well as the right ventricular ejection fraction at rest of 15.10% and 14.88% with stress. In addition, functional class improved in 35%, and the maximum amplitude time/total time (MAT/TT) index decreased 23.1%. These changes were statistically significant compared with the control group. CONCLUSIONS: Citrulline supplementation significantly improved the LVEF, the endothelial function (MAT/TT index) and functional class. Citrulline can be an important co-adjuvant in the treatment of stable and stable systolic heart failure patients.