Left Volume Research Articles

Effect of trimetazidine on left ventricular functions and cardiac biomarkers in diabetic patients with left ventricular diastolic dysfunction: a randomized controlled trial

We investigated the impact of trimetazidine treatment on left ventricular (LV) functions and cardiac biomarkers in diabetic patients with diastolic dysfunction as an early stage of diabetic cardiomyopathy. Sixty-three patients were randomly assigned to receive either trimetazidine or a placebo for 3 months. At baseline and after 3-months of treatment, measurements of serum levels of glycemic control parameters, lipid profile, tumor necrosis factor alpha, transforming growth factor beta 1, n-terminal pro brain natriuretic peptide and assessment of modified Medical Research Council (mMRC) dyspnea score, echocardiographic indices of LV functions and LV global longitudinal strain (GLS) were performed. After 3-months, trimetazidine group exhibited a significant reduction in left atrial volume index by 6.99% versus an increase by 0.66% in placebo group, p = 0.034. Moreover, average e’ increased by a significantly higher percentage in trimetazidine versus placebo group (8.46 ± 18.64 vs. -2.49 ± 14.52, respectively. p = 0.015). Trimetazidine treatment resulted in a significant increase in LVGLS by 6.66% versus LVGLS reduction by 2.79% in placebo group (p = 0.004). Trimetazidine group had a significantly lower median mMRC dyspnea score compared to placebo (0 vs. 1, respectively, p = 0.015) and a significantly lower low-density lipoprotein (LDL-C) (103.43 ± 28.31 vs. 125.34 ± 45.27, respectively, p = 0.032). There was no significant difference between both groups in levels of other biomarkers. Three-months treatment with trimetazidine improved diastolic function parameters, LVGLS, dyspnea severity and LDL-C levels in diabetic patients with diastolic dysfunction.

Cardiac computer tomography-derived radiomics in assessing myocardial characteristics at the connection between the left atrial appendage and the left atrium in atrial fibrillation patients

ObjectivesTo evaluate the feasibility of utilizing cardiac computer tomography (CT) images for extracting the radiomic features of the myocardium at the junction between the left atrial appendage (LAA) and the left atrium (LA) in patients with atrial fibrillation (AF) and to evaluate its asscociation with the risk of AF.MethodsA retrospective analysis was conducted on 82 cases of AF and 56 cases in the control group who underwent cardiac CT at our hospital from May 2022 to May 2023, with recorded clinical information. The morphological parameters of the LAA were measured. A radiomics model, a clincal feature model and a model combining radiomics and clinical features were constructed. The radiomics model was built by extracting radiomic features of the myocardial tissue using Pyradiomics, and employing Least absolute shrinkage and selection operator (LASSO) method for feature selection, combining random forest with support vector machine (SVM) classifier.ResultsThere were 82 cases in the AF group [44 males, 65.00 (59, 70)], and 56 cases in the control group (21 males, 61.09 ± 7.18). Age, BMI, hypertension, CHA2DS-VASC score, neutrophil to lymphocyte ratio (NLR), LAA volume, LA volume, the myocardial thickness at the junction of LAA and LA, the area, circumference, short diameter, and long diameter of the LAA opening, were significantly different between the AF group and the control group (P < 0.05). After conducting multivariate logistic regression analysis, it was found that BMI, the myocardial thickness at the junction of the LAA and the LA, LA volume, NLR and CHA2DS-VASC score were related to AF. 12 radiomics features of the myocardium at the junction of the LAA and the LA were extracted and identified. ROC curve analysis confirmed that the nomogram based on radiomics scores and clinical factors can effectively predict AF (AUC 0.869).ConclusionRadiomics enables the extraction of the myocardial characteristics at the junction of the LAA and the LA, which are related with AF, facilitating the assessment of its relationship with the risk of AF. The combination of radiomics with clinical characteristics enhances the evaluation capabilities significantly.

Is early use of sodium-glucose cotransporter type 2 inhibitor (SGLT2i) necessary even in diabetic patients without cardiovascular disease: a prospective study regarding the effect of SGLT2i on left ventricular diastolic function

BackgroundThere are insufficient studies to determine whether sodium-glucose cotransporter type 2 inhibitors (SGLT2i) will help reduce early diabetic cardiomyopathy, especially in patients without documented cardiovascular disease.MethodsWe performed a single center, prospective observation study. A total of 90 patients with type 2 diabetes patients without established heart failure or atherosclerotic cardiovascular disease were enrolled. Echocardiography, cardiac enzyme, and glucose-control data were examined before and 3 months after the administration of SGLT2i (dapagliflozin 10 mg per day). Cardiovascular risk factors included hypertension, smoking, obesity, dyslipidemia, and old age. The primary end point was the change of E/e’ before and after administration of SGLT2i.ResultsMost patients (86.7%) had three or more cardiovascular risk factors, and about 32% had all five risk factors. Although the decrease in E/e’ after the administration of SGLT2i was observed in 20% of enrolled patients, there was no significant difference in average E/e’ value or left atrial volume index before and after the SGLT2i medication. Even in patients with all known risk factors including old age, E/e’ value did not decrease after adding SGLT2i (8.9 ± 2.4 vs. 8.7 ± 3.2). There was a statistically significant difference in E/e’ change after the SGLT2i administration between patients younger than 60 years and those older than 60 years (–0.7 ± 2.2 vs. 1.1 ± 2.8, P = 0.002).ConclusionsIn type 2 diabetes patients without documented cardiovascular disease including heart failure, administration of SGLT2i showed no improvement in diastolic function profile. Further large-scale randomized studies are needed to determine who will benefit from potential cardiovascular events with early addition of SGLT2i.

Optimized workflow with hybrid (very) high-power short-duration radiofrequency ablation renders point-by-point pulmonary vein isolation as fast and effective as cryoballoon ablation.

A hybrid approach with very high-power short-duration (vHPSD) posteriorly and ablation-index guided HPSD (50 W) anteriorly seems to be an optimal balance between efficiency and effectiveness for point-by-point pulmonary vein isolation (PVI). The aim of the current study is to compare vHPSD/HPSD ablation to cryoballoon ablation (CBA) in patients with symptomatic atrial fibrillation (AF). In this retrospective single-center study, we identified 110 consecutive patients who underwent their first PVI with either vHPSD/HPSD (n = 54) or CBA (n = 56). We compared procedural efficacy, efficiency, safety, and long-term outcomes. Baseline characteristics of both groups were comparable; however, patients in the vHPSD/HPSD group had larger left atrial volume index (35, IQR 27-45 vs. 28, IQR 21-36ml/m2, P = 0.005). Complete PVI was achieved in all patients except two CBA cases (100% vs. 96.4%, P = 0.50). First-pass isolation rate was 79.6% in the hybrid group. Procedure times were similar between groups (53, IQR 47-63 vs. 55, IQR 49-65min, P = 0.35), but fluoroscopy time was shorter in the vHPSD/HPSD group (3.9 [2.7, 5.6] vs. 11.9 [9.3, 14.9] min, P < 0.001). There were 3 temporary phrenic nerve palsies (5.4%) in the CBA group which resolved within 1year. The 1-year freedom from any atrial tachyarrhythmias after a single procedure was similar between groups (68.5% vs. 73.2%, P = 0.56). During repeat procedure, the durability of PVI was comparable. The use of vHPSD/HPSD ablation renders point-by-point PVI as fast and effective as CBA. Furthermore, it has lower radiation exposure compared to CBA.

Clinical, Imaging, and Atrial Cardiopathy Markers in Ischemic Stroke Subtypes - Clues to a Cardioembolic Source.

Cryptogenic strokes account for 20%-25% of all ischemic strokes. Although atrial cardiopathy markers are more prevalent in the cryptogenic embolic stroke of undetermined source (ESUS) subgroup than in the nonembolic stroke subgroup, the utility of individual parameters in predicting cardioembolic sources needs to be studied further. We studied the clinical, imaging, and atrial cardiopathy markers in three ischemic stroke subtypes - large artery atherosclerosis (LAA), cardioembolism (CE), and cryptogenic ESUS - and their role in predicting the source of CE. This was a prospective observational study of ischemic stroke patients at Department of Neurology, Sree Chitra Tirunal Institute for Medical Sciences and Technology, Trivandrum from April 2021 to December 2022. Clinical and risk factor profiles, imaging details, atrial cardiopathy marker (N-terminal pro-brain natriuretic peptide [NT-pro-BNP]) levels, electrocardiogram (ECG) parameters (P terminal force of V1 [PTFV1], P wave duration, the PR interval), and transthoracic echo parameters (left atrial [LA] diameter and LA volume) were collected. Associations were made between clinical, imaging, and atrial cardiopathy markers and etiological subtypes. We had 255 participants (LAA- 98, CE- 41, and ESUS- 139) with a mean age of 63.53 years. Among the atrial cardiopathy markers, the most prevalent was elevated NT-pro-BNP (43.95%), followed by the ECG markers P wave duration (30.92%) and PTFV1 (28.74%), and LA diameter greater than 37 mm (24.27%) and LA volume greater than 34 ml/m2 (20.31%). Among the atrial cardiopathy markers, NT-pro-BNP and LA enlargement were strongly predictive of CE etiology, when compared to LAA. Chronic non-lacunar infarcts on imaging and elevated NT-pro-BNP showed a strong association with CE, when compared to cryptogenic strokes. The atrial cardiopathy biomarker NT-pro-BNP and chronic non-lacunar infarcts can serve as useful tools for recognizing cardioembolic sources among patients with embolic strokes.

Prognostic value of left atrioventricular coupling index in heart failure.

To investigate the distribution of left atrioventricular coupling index (LACI) among patients with heart failure and left ventricular ejection fraction (LVEF)<50% and to explore its association with the combined endpoint of all-cause death or HF hospitalization at long term follow-up. Patients with HF and LVEF<50% undergoing cardiac magnetic resonance (CMR) were evaluated. Patients with atrial fibrillation or flutter were excluded. LACI was measured as the ratio between the left atrial (LA) and the LV end-diastolic volumes. Patient population was divided according to LACI tertiles and followed-up. Total of 478 patients (mean age 62±12 years, 78% male) were included. The median value of LACI was 27.1% (interquartile range 19.9-34.5). Patients within the worst LACI tertile (≥30.9%) showed smaller LV volumes and larger LA volumes as compared to patients in the first or second tertile (LACI 6.2-22.2 and LACI 22.3-30.9; respectively). LACI was significantly associated with the combined endpoint (hazard ratio [HR] 1.87, p=0.01). After adjusting for sex, age, ischemic HF aetiology, LVEF, LA reservoir strain, diabetes mellitus, LV scar, mitral regurgitation and LVEDVi, LACI remained significantly associated with the combined endpoint (HR 1.77, p=0.02). Patients with highest LACI values had worse outcomes compared to patients in first and second tertiles (HR 1.69, p=0.02 and HR 1.77, p=0.02; respectively). In patients with HF and LVEF <50%, LACI is independently associated with adverse events. Patients with most impaired left atrioventricular coupling have the worst clinical outcomes.

Predicting mortality after transcatheter aortic valve replacement using AI-based fully automated left atrioventricular coupling index.

This study aimed to determine whether artificial intelligence (AI)-based automated assessment of left atrioventricular coupling index (LACI) can provide incremental value above other traditional risk factors for predicting mortality among patients with severe aortic stenosis (AS) undergoing coronary CT angiography (CCTA) before transcatheter aortic valve replacement (TAVR). This retrospective study evaluated patients with severe AS who underwent CCTA examination before TAVR between September 2014 and December 2020. An AI-prototype software fully automatically calculated left atrial and left ventricular end-diastolic volumes and LACI was defined by the ratio between them. Uni- and multivariate Cox proportional hazard methods were used to identify the predictors of mortality in models adjusting for relevant significant parameters and Society of Thoracic Surgeons Predicted Risk of Mortality (STS-PROM) score. A total of 656 patients (77 years [IQR, 71-84 years]; 387 [59.0​%] male) were included in the final cohort. The all-cause mortality rate was 21.6​% over a median follow-up time of 24 (10-40) months. When adjusting for clinical confounders, LACI ≥43.7​% independently predicted mortality (adjusted HR, 1.52, [95​% CI: 1.03, 2.22]; p​=​0.032). After adjusting for the STS-PROM score in a separate model, LACI ≥43.7​% remained an independent prognostic parameter (adjusted HR, 1.47, [95​% CI: 1.03-2.08]; p​=​0.031). In a sub-analysis of patients with preserved left ventricular ejection fraction, LACI remained a significant predictor (adjusted HR, 1.72 [95​% CI: 1.02, 2.89]; p​=​0.042). AI-based fully automated assessment of LACI can be used independently to predict mortality in patients undergoing TAVR, including those with preserved LVEF.

Relationship between left atrial volume and macrovascular disease in type 2 diabetes mellitus

Relationship between left atrial volume and macrovascular disease in type 2 diabetes mellitus

Device endothelialization and morphology assessments at 1 year using computed tomography angiography: comparison of traditional with novel puncturable atrial septal defect occluders

BackgroundComplete endothelialization is often not achieved within 6 months after implantation of an atrial septal defect (ASD) occluder, which may lead to microthrombus or thrombosis. This study aimed to assess the endothelialization and morphology of a novel puncturable ASD occluder (ReAces) compared with traditional occluders 1 year post-implantation using computed tomography angiography (CTA).MethodsFifteen patients from each group in a randomized controlled trial comparing ReAces with traditional occluders were included at the 1-year follow-up at Zhongshan Hospital, Fudan University. Baseline characteristics and procedural data were recorded. CTA was performed to assess the device morphology and degree of endothelialization. Independent samples t-test and Fisher's exact test were primarily used to compare the above data.ResultsEach patient received a single device and had no residual shunts. There were no differences in defect size (15.3 ± 4.0 mm vs. 15.3 ± 4.7 mm, p = 1.00) or occluder size (21.2 ± 4.4 mm vs. 21.5 ± 5.3 mm, p = 0.882) between the two groups. At the 1-year follow-up CTA, the central region thickness (4.2 mm ± 0.9 mm vs. 7.8 mm ± 2.4 mm, p < 0.0001), left atrial device-occupied volume (1863.3 mm2 ± 404.4 mm2 vs. 4764.4 mm2 ± 2321.2 mm2, p < 0.001), and device compression rates (10.1 ± 4.8% vs. 17.5 ± 5.6%, p = 0.001) were significantly lower in the experimental group. All occluders in the experimental group achieved complete endothelialization, whereas in the control group, 7 patients did not (100% vs. 53.3%, p = 0.006).ConclusionsCompared with traditional occluders, ReAces presented a significantly greater complete endothelialization rate, lower central region thickness, lower left atrial device-occupied volume, and lower device compression rates at 1 year post-implantation by CTA.Trial registrationTrial registry: ClinicalTrials.gov.Unique identifying number: NCT05371366.Date of registration: 04/05/2022.Graphical

Diagnostic value of left atrial compliance in determining heart failure with preserved ejection fraction

Objective — To study the diagnostic value of left atrial (LA) compliance using transthoracic echocardiogram (TTE) at rest in determining of the heart failure with preserved ejection fraction (HFpEF) depending on the result of diastolic stress test (DST). Materials and Methods — We examined 200 patients (46.5% men, 66.0±5.8 years of age). Patients with elevated left ventricular (LV) filling pressure according to TTE at rest constituted Group I (n=34). Patients with impaired diastolic reserve according to DST constituted Group II (n=68); patients without HFpEF were placed in Group III (n=98). Speckle tracking echocardiography was used to assess left atrial reservoir strain (LASr). Results — The groups were similar in terms of key clinical characteristics, with the exception of coronary artery disease (79.4% vs. 86.8% vs. 66.7%, respectively, p=0.011) and NYHA heart failure class (2.0±0.6 vs. 1.9±0.4 vs. 1.7±0.6; p=0.002). Statistically significant differences were also found in NT-proBNP (500.0 [261.3;817.0] pg/ml vs. 256.7 [93.9;456.3] pg/ml vs. 183.8 [60.1;310.4] pg/ml, p&lt;0.001) and both pre-test scoring scales, HFA-PEFF (6.0 [5.0;6.0] vs. 5.0 [4.0;6.0] vs. 4.0 [3.0;5.0], p&lt;0.001) and H2FPEF (5.0 [3.0;6.0] vs. 5.0 [3.0;5.0] vs. 4.0 [3.0;5.0], p=0.001). Statistically significant differences between Groups I and II and Groups I and III were detected for most echocardiographic parameters. No significant differences were found between Groups II and III, except for the following parameters: E/e’ (11.2 [9.8; 12.6] vs. 9.3 [7.7; 10.9], respectively, p&lt;0.001), LASr (21.4 [19.8; 24.5] % vs. 27.6 [24.6; 29.8] %, p &lt; 0.001) and LA compliance (2.0 [1.6; 2.4] vs. 3.0 [2.4; 3.7], p&lt;0.001). According to ROC analysis, the largest area under the curve (AUC), as well as optimal sensitivity and specificity in determining HFpEF in Groups II and III, were observed for LA compliance (AUC=0.837, p&lt;0.001; 76.5% and 76.5%). Lower classification quality was demonstrated by the left atrial volume index (LAVI)/LASr (AUC=0.720, p&lt;0.001; 69.1% and 62.2%), H2FPEF scale (AUC=0.629, p=0.006; 60.3% and 65.3%), NT-proBNP (AUC=0.615, p=0.014; 60.0% and 58.1%), and HFA-PEFF score (AUC=0.610, p=0.019; 60.3 and 54.1%). Conclusion — LA compliance with the cutoff point &lt;2.4 has the highest ability to detect HFpEF depending on the DST result among all pre-test diagnostic tools.

Echocardiographic Changes Following Surgical Myectomy in Severely Symptomatic Obstructive Hypertrophic Cardiomyopathy: Insights From the SPIRIT-HCM Study.

In obstructive hypertrophic cardiomyopathy, myectomy improves symptoms, quality of life, and left ventricular (LV) outflow tract gradients. We prospectively evaluated the temporal changes in various echo parameters after myectomy. In 173 adults with obstructive hypertrophic cardiomyopathy (53±10 years, 63% men) who underwent myectomy between March 2017 and June 2020, clinical and blinded echo assessment (before and at 12±6 months follow-up) was performed prospectively (SPIRIT-HCM [Quality of Life and Functional Capacity Following Septal Myectomy in Obstructive Patients With Hypertrophic Cardiomyopathy]). Changes in echocardiographic parameters (left atrial volume index, E/e', LV outflow tract gradients, along with average LV global longitudinal strain on apical 2-, 3-, and 4-chamber views and regional LV strain from apical 4-chamber view) were measured in 126 patients. There was significant improvement in left atrial volume index (-6.9 mL/m2 [95% CI, 4-9.7]), E/e' (-2.9 [95% CI, -2.7 to -4.1]) and peak LV outflow tract gradient (-94 mm Hg [95% CI -87 to -100]) from baseline to follow-up (both P<0.001). There was no improvement in basal (0.91% [95% CI, -0.15 to 1.97], P=0.09) and midseptal (-0.98% [95% CI, -1.93 to 0.02], P=0.05) LV strain, worsening in apical septal strain (-4.5% [95% CI, -5.9 to -3.0], P<0.001) and an improvement in LV free wall strain (2.3% [95% CI, 0.67-3.9], P<0.001), with no change in overall LV-global longitudinal strain (0.47% [95% CI, -0.43 to 1.37], P=0.30). There was no correlation between change in LV-global longitudinal strain and change in 6-minute walk time (r=0.12, P=0.24) or Kansas City Cardiomyopathy Questionnaire summary score change (r=0.02, P=0.85), whereas it was significantly associated with change in E/e' (r=0.29, P=0.003). In patients with obstructive hypertrophic cardiomyopathy, myectomy improved various echocardiography parameters at 1-year; however, LV-global longitudinal strain remained unchanged. URL: https://clinicaltrials.gov; Unique identifier: NCT03092843.

Machine Learning‐Driven Identification of Distinct Persistent Atrial Fibrillation Phenotypes: A Cluster Analysis of DECAAF II

ABSTRACTIntroductionCatheter ablation of persistent atrial fibrillation yields sub‐optimal success rates partly due to the considerable heterogeneity within the patient population. Identifying distinct patient phenotypes based on post‐ablation prognosis could improve patient selection for additional therapies and optimize treatment strategies.MethodsWe studied all patients who underwent catheter ablation of persistent atrial fibrillation in the DECAAF II trial. Out of 44 participating centers, 25% were randomly chosen as a validation set. A Gradient Boosting Method determined essential features for arrhythmia recurrence prediction and the number of clusters was determined according to the average silhouette width. K‐medoids cluster analysis identified subgroups based on these features, and Kaplan–Meier curves were further compared among different clusters.ResultsAmong 815 patients, 570 served as a training set and 245 as a validation set. Using the training set, the GBM model achieved an AUC of 0.874. K‐medoids cluster analysis used LA volume, BMI, baseline fibrosis, and age, resulting in two clusters. Cluster 1 patients were older, had higher baseline fibrosis, higher BMI, and greater LA volume compared to Cluster 2. Atrial arrhythmia recurrence rates were significantly higher in Cluster 1 (51.7% vs. 35.0%, p = 0.0002), and survival analysis showed a significant difference in primary recurrence outcomes (HR = 1.71, p &lt; 0.0001). The validation set confirmed these findings.ConclusionUtilizing machine learning, we identified a high‐risk cluster for procedural failure in catheter ablation of persistent atrial fibrillation within the DECAAF II trial population. The primary differentiating factors of this high‐risk cluster include older age, high left atrial fibrosis, elevated BMI, and increased left atrial volume.

Using clinical data to reclassify ESUS patients to large artery atherosclerotic or cardioembolic stroke mechanisms.

Embolic stroke of unidentified source (ESUS) represents 10-25% of all ischemic strokes. Our goal was to determine whether ESUS could be reclassified to cardioembolic (CE) or large-artery atherosclerosis (LAA) with machine learning (ML) using conventional clinical data. We retrospectively collected conventional clinical features, including patient, imaging (MRI, CT/CTA), cardiac, and serum data from established cases of CE and LAA stroke, and factors with p < 0.2 in univariable analysis were used for creating a ML predictive tool. We then applied this tool to ESUS cases, with ≥ 75% likelihood serving as the threshold for reclassification to CE or LAA. In patients with longitudinal data, we evaluated future cardiovascular events. 191 ischemic stroke patients (80 CE, 61 LAA, 50 ESUS) were included. Seven and 6 predictors positively associated with CE and LAA etiology, respectively. The c-statistic for discrimination between CE and LAA was 0.88. The strongest predictors for CE were left atrial volume index (OR = 2.17 per 1 SD increase) and BNP (OR = 1.83 per 1 SD increase), while the number of non-calcified stenoses ≥ 30% upstream (OR = 0.34 per 1 SD increase) and not upstream (OR = 0.74 per 1 SD increase) from the infarct were for LAA. When applied to ESUS cases, the model reclassified 40% (20/50), with 11/50 reclassified to CE and 9/50 reclassified to LAA. In 21/50 ESUS with 30-day cardiac monitoring, 1/4 in CE and 3/16 equivocal reclassifications registered cardiac events, while 0/1 LAA reclassifications showed events. ML tools built using standard ischemic stroke workup clinical biomarkers can potentially reclassify ESUS stroke patients into cardioembolic or atherosclerotic etiology categories.

Aberration correction—impact on image quality and chamber quantification in transthoracic echocardiography

Abstract Aims To improve image quality (IQ) in echocardiography, an aberration correction (AC) algorithm has recently been implemented in commercial scanners. We aimed to study (i) the correlation of a subjective IQ-score and an objective IQ-metric [global image coherence (GIC)], (ii) if AC improved IQ; (iii) if AC affected average values and interobserver agreement of left ventricular (LV) size, LV longitudinal strain, and left atrial (LA) volume. Methods and results From 50 adult patients, where 45 (90%) had cardiovascular disease, unprocessed image data (channel data) were acquired from six standard transthoracic views. The data were processed with and without AC, resulting in 300 pairs of cine-loops. The cine-loops were randomly presented one-by-one to two blinded raters experienced in echocardiography. Both raters scored IQ subjectively from 1 (poor) to 4 (very good) and quantified LV dimensions, volumes and longitudinal strain, and LA volume. IQ-score correlated with GIC, Spearman rho 0.72, P &amp;lt; 0.001. AC improved median IQ-score from 2.5 to 3.0 (Wilcoxon signed rank: P &amp;lt; 0.001). The differences in average values of LV size, LV longitudinal strain, or LA volume with and without AC were not statistically significant and numerically minimal. Measured by intraclass correlation, interobserver agreement of these values was not significantly affected by AC. Conclusion Image quality-score strongly correlated with GIC. Aberration correction improved IQ. However, AC did not lead to statistically significant changes in average values or interobserver agreement of LV size, LV longitudinal strain or LA volume quantification. Likely, the major benefit of AC is enhanced visualization of anatomical details.

Prediction of new-onset atrial fibrillation in patients with hypertrophic cardiomyopathy using machine learning.

Atrial fibrillation (AF) is the most common sustained arrhythmia among patients with hypertrophic cardiomyopathy (HCM), leading to increased symptom burden and risk of thromboembolism. The HCM-AF score was developed to predict new-onset AF in patients with HCM, though sensitivity and specificity of this conventional tool are limited. Thus, there is a need for more accurate tools to predict new-onset AF in HCM. The objective of the present study was to develop a better model to predict new-onset AF in patients with HCM using machine learning (ML). In this prospective, multicentre cohort study, we enrolled 1069 patients with HCM without a prior history of AF. We built a ML model (logistic regression with Lasso regularization) using clinical variables. We developed the ML model using the cohort from one institution (training set) and applied it to an independent cohort from a separate institution (test set). We used the HCM-AF score as a reference model. We compared the area under the receiver-operating characteristic curve (AUC) between the ML model and the reference model using the DeLong's test. Median follow-up time was 2.1 years, with 128 (12%) patients developing new-onset AF. Using the ML model developed in the training set to predict new-onset AF, the AUC in the test set was 0.84 (95% confidence interval [CI] 0.77-0.91). The ML model outperformed the reference model (AUC 0.64; 95% CI 0.54-0.73; DeLong's p < 0.001). The ML model had higher sensitivity (0.82; 95% CI 0.65-0.93) than that of the reference model (0.67; 95% CI 0.52-0.88). The ML model also had higher specificity (0.76; 95% CI 0.71-0.81) than that of the reference model (0.57; 95% CI 0.41-0.70). Among the most important clinical variables included in the ML-based model were left atrial volume and diameter, left ventricular outflow tract gradient with exercise stress and at rest, late gadolinium enhancement on cardiac magnetic resonance imaging, peak heart rate during exercise stress, age at diagnosis, positive genotype, diabetes mellitus, and end-stage renal disease. Our ML model showed superior performance compared to the conventional HCM-AF score for the prediction of new-onset AF in patients with HCM.

Epigenetic regulation on left atrial function and disease recurrence after catheter ablation in atrial fibrillation

BackgroundGenetic variation and modifiable risk factors play a significant role in the pathogenesis of atrial fibrillation (AF). The influence of epigenetic modification on AF remains to be elucidated. We investigated the role of DNA methylation in the etiology of AF. Epigenetic evaluation was performed in 115 AF patients who underwent radiofrequency catheter ablation in a single institution. We measured methylation at approximately 850,000 bp cytosine-phosphate-guanine (CpG) sites in the 115 samples. The degree of methylation was compared across seven classification criteria: type of AF, late recurrence, impaired left atrium (LA) function, late gadolinium enhancement, LA diameter, LA volume, and flow velocity of the LA appendage.ResultsThe four most significantly methylated genes were DEFB104B, C3, TANC1, and TMEM9B. The DEFB104B gene (cg20223677 in the transcription start site), which encodes β-defensin 104B, was hypomethylated in three groups: AF patients with late recurrence, impaired LA function, and impaired LAA flow velocity. Enriched functional annotation of the differentially methylated datasets revealed that five out of the seven AF groups in this cohort were associated with genes involved in the cell movement of endothelial cell lines, sprouting angiogenesis by endothelial cell lines, or migration of endothelial cell lines.ConclusionsEpigenetic profiling revealed that epigenetic modification might affect important characteristics of AF. Our results suggest that the pathogenesis of AF might be affected by not only genetic variation or modifiable factors but also by epigenetic modulation.

Speckle Tracking Echocardiography-Based Correlation Between Left Atrial Strain and Functional Capacity in Patients With Hypertrophic Cardiomyopathy.

The left atrium (LA) dilates and its function decreases as a chronic secondary change in hypertrophic cardiomyopathy (HCM). LA strain is a more sensitive measure of LV filling pressure than LA volume and can be used to predict the functional capacity in HCM. To analyze LA strain in patients with HCM and its correlation with exercise tolerance. A total of 113 patients with HCM were enrolled. All patients underwent detailed clinical evaluation, 24-h Holter monitoring, exercise stress testing, two-dimensional echocardiography with LA strain analysis using speckle tracking imaging. Assessment of functional capacity was done in terms of metabolic equivalents (METs). HCM patients with METS >6.0 were included in Group A while those with METS ≤6.0 were included Group B. Correlation of various parameters of LA strain (left atrial reservoir strain [LASr], left atrial conduit strain [LAScd], and left atrial contraction strain [LASct]) was done with functional capacity. The mean age of the study population was 47±10.77 years with the majority of them being males (71.9%). Group B patients had significantly lower LASr (12.95%±8.61% vs. 22.16%±16%; p<0.001), LAScd (-7.28%±6.29% vs. -12.74%±8.40%; p<0.001), and LASct (-7.44±4.46 vs. -11.19±6.53; p<0.001). Multivariable linear regression analysis reported LASr to be an independent predictor of METs and had a quadratic relationship with log-odds with negative linear and positive quadratic coefficients. LASr was the strongest echocardiographic predictor of reduced METS with an AUC of 0.78 (95% confidence interval [CI]: 0.68-0.88), sensitivity of 71.8%, and specificity of 82.9%. LA strain parameters are associated with functional capacity in patients with HCM with lower LA strain values being associated with poor functional capacity.

Dose to cardiac substructures and cardiovascular events in esophageal cancer patients treated with definitive radiotherapy

IntroductionWhile there is a growing amount of data on the cardiac toxicity of radiotherapy (RT) in relation to its impact on cardiac sub-structures (CSS), there are only few studies addressing this issue in patients followed for esophageal cancer (ESOC). We aimed to evaluate the association between independent parameters of dose received by CSS and major cardiac events (MACEs) in this population.Materials and methodsWe retrospectively analyzed 122 patients treated with exclusive RT or chemo-RT for ESOC. Heart and CSS i.e. right atrium, left atrium (LA), right ventricle, left ventricle and myocardium, have been automatically segmented, and dose volume histogram were extracted. Cardiac events were collected focusing on the occurrence of MACEs of grade 3 or higher (G3+) and grade 4 or higher (G4+) according to the CTCAE v5.0.ResultsWith a median follow-up of 21.9 months and in a population of high to very high cardiovascular risk (95.5%), 21 (17.2%) and 9 (7.4%) patients had G3 + and G4 + MACEs with a respective median time to event of 13.05 and 9.8 months. After multivariate analysis and among all heart and CSS-based dosimetric features, only the volume of LA receiving 15 Gy or more (V15LA) remained significantly associated with the G3 + and G4 + MACEs. The use of volumetric modulated arctherapy significantly reduced V15LA compared with 3D conformal RT.ConclusionIn a cohort of ESOC patients treated with exclusive RT, incidence of MACEs was associated with V15LA, underlining the importance of CSS. These high cardiovascular (CV) risk patients should benefit from standard CV assessment and strict control of their risk factors.

Empagliflozin to prevent worsening of left ventricular volumes and systolic function after myocardial infarction (EMPRESS-MI).

Patients with a reduced left ventricular ejection fraction (LVEF) following an acute myocardial infarction (MI) are considered to be at risk of progressive adverse cardiac remodelling which can lead to the development of heart failure and death. The early addition of a sodium-glucose cotransporter 2 (SGLT2) inhibitor to standard treatment may delay or prevent progressive adverse remodelling in these patients. We performed a randomized, double-blind, placebo-controlled, multicentre trial using cardiovascular magnetic resonance imaging (MRI), in patients with left ventricular systolic dysfunction following MI. Eligible patients were those ≥12 h and ≤14 days following acute MI, with an LVEF <45% by MRI. Patients were randomized to empagliflozin 10 mg once a day or matching placebo. The primary outcome was the change in left ventricular end-systolic volume indexed to body surface area (LVESVI) from baseline to 24 weeks. Secondary outcomes included measures of left ventricular and atrial volumes, left ventricular mass, LVEF, and high-sensitivity troponin I (hs-TnI) and N-terminal prohormone of B-type natriuretic peptide (NT-proBNP) concentrations. From October 2022 to January 2024, 105 eligible patients were randomized. The mean age was 63 ± 11 years and 90 (87%) were male. The mean LVEF was 34.8 ± 6.0%. In the placebo group, LVESVI decreased by 7.8 ± 16.3 ml/m2, left ventricular end-diastolic volume index (LVEDVI) did not change (-0.3 ± 18.7 ml/m2) and LVEF increased by 8.5 ± 7.4% at 24 weeks from baseline. Empagliflozin did not affect the change in LVESVI from baseline to 24 weeks (between-group difference = 0.3 ml/m2, 95% confidence interval -5.2 to 5.8; p = 0.92). Compared with placebo, empagliflozin also had no effect on LVEDVI, LVEF, left atrial volume index, left ventricular mass index, NT-proBNP, or hs-TnI, but did increase haematocrit and reduced uric acid and weight. In patients with left ventricular systolic dysfunction after an acute MI receiving contemporary standard of care, treatment with empagliflozin had no effect on cardiac volumes or LVEF compared with placebo. Progressive adverse cardiac remodelling did not occur in the majority of patients.

Left Atrial Functional and Structural Characteristics in Patients After Total and Bicaval Orthotopic Heart Transplantation

Background/Objectives: Currently, the most popular techniques for orthotopic heart transplantation (OHTx) are bicaval and total OHTx. Although bicaval OHTx has shown advantages over the biatrial approach, comparisons between bicaval and total OHTx reain limited. To compare the functional and morphological characteristics of the left atrium (LA) in patients after bicaval and total OHTx. Methods: Sixty-six patients (age 51.2 ± 10.5 years) after total OHTx (33 patients) and bicaval OHTx (33 patients) were included in this case–control study. Recipients were matched for sex, age, and time from transplantation and absence of severe graft rejection based on routine endomyocardial biopsies (EMB) performed during follow-up. Echocardiography included standard measurements along with a speckle-tracking assessment of LA strain. Results: Compared with the bicaval OHTx, the total OHTx group showed higher atrial mitral inflow velocity, resulting in a lower E/A ratio, lower LA volume index, and higher LA emptying fraction. Both the reservoir and contraction components of LA function, as assessed by LA deformation, were found to show more favorable profiles in the total OHTx group than in the bicaval group (26.5 ± 6.9 vs. 17.4 ± 4.7, p &lt; 0.001 and 14.8 ± 5.8 vs. 6.0 ± 4.5, p &lt; 0.001, respectively). Multivariable analysis identified surgical technique, left ventricular global longitudinal strain, and the presence of diabetes in the recipient as independent determinants of LA strain. Conclusions: Total OHTx is associated with better LA morphology and function than bicaval OHTx. This may provide better conditions for LA-LV coupling in transplanted hearts and contribute to a more stable electrophysiological environment in atrial tissue.