Severe Mitral Regurgitation Research Articles

Abstract 4116281: Improvement in Valvular Regurgitation Severity with Atrioventricular Junction Ablation: Conduction System and Biventricular Devices

Background: Ablate-and-pace strategies for permanent atrial fibrillation (AF) have shown mortality benefit with biventricular pacemakers (BiV). The mechanism of benefit is not well understood, but may involve cardiac remodeling. We sought to characterize the effects of AV junction ablation (AVJA) in patients receiving BiV or conduction system pacing (CSP) devices on valvular regurgitation. Objective: To evaluate the effects of AVJA in permanent AF on valvular regurgitation as measured by standard 2D echocardiography. Methods: Consecutive patients undergoing BiV/CSP after AVJA for permanent AF with tricuspid regurgitation (TR) and/or mitral regurgitation (MR) between January 2018 and January 2023 at our institution were analyzed. Ejection fraction (EF), TR severity, and MR severity were compared pre-AVJA and post-AVJA. Results: A total of 102 patients met the above criteria. Median clinical follow up time was 902 days (IQR 578-1537 days) from AVJA. In patients with at least 1+ MR at baseline (N=65), there was significant improvement in MR severity post-AVJA (p=0.003). At baseline, 51% of patients had 1+ MR, 36% of patients had 2+ MR, 10% of patients had 3+, and 3% of patients had 4+ MR. Post AVJA, 45% (29 patients) had improvement in MR severity, 40% (26 patients) had no change, and 15% (10 patients) worsened. The greatest improvement was seen in patients with reduced baseline EF(defined as EF<50%). All 3+ and 4+ MR improved to at least 2+ MR post-AVJA in this subset. In patients with at least 2+ TR at baseline (N=28), there was also significant improvement in TR severity (p=0.029). Conclusion: AVJA with physiologic pacing in patients with permanent AF is associated with improvement in MR and TR severity.

Abstract 4137726: A Deep Learning Digital Biomarker for Mitral Valve Prolapse using Echocardiogram Videos

Background: Mitral valve prolapse (MVP) has a prevalence of 2–3% and is a risk factor for heart failure and sudden death, but MVP diagnosis by transthoracic echocardiography (TTE) requires time and clinical expertise. We trained a deep learning model to classify MVP from TTE videos. Methods: DROID-MVP is a convolutional neural network trained to classify MVP using echocardiographer labels using 973,531 digital videos (parasternal long axis and apical views) from 45,657 studies performed in 15,728 cardiology patients at Massachusetts General Hospital. We validated DROID-MVP in 1,726 cardiology patients (4,869 studies) and 8,903 primary care patients (8,903 studies), and tested associations between predicted MVP score (range 0-1) and mitral regurgitation (MR) severity and left atrial (LA) anterior-posterior diameter in primary care patients with available measurements. Results: Of 15,728 patients (6,029 [38%] women; mean age at first TTE 61 ± 17 years) in the training set, 729 (4.6%) had at least 1 study with MVP. DROID-MVP identified MVP in both the cardiology (area under the receiver operating characteristic curve [AUC] 0.955 [95% confidence interval: 0.939-0.970]; average precision [AP] 0.716 [0.649-0.776]; prevalence 0.035) and primary care (AUC 0.966 [0.955-0.978]; AP 0.668 [0.601-0.730]; prevalence 0.022) test sets ( Figure 1 ). Discrimination persisted across strata of MR severity (AUC range 0.877-0.987). High (>0.67) vs low (<0.33) MVP score was associated with higher odds of moderate/severe MR (odds ratio 20.1 [12.2-33.4], p<0.001) and higher LA diameter (2.7 [0.9-4.4] mm, p<0.001; Figure 2 ), after adjusting for age, sex, height, and weight. Conclusions: A deep learning model identifies MVP from TTE videos with excellent discrimination and higher model predictions are associated with greater MR severity and LA size. Our work demonstrates how deep learning can automate MVP diagnosis and may serve as a digital biomarker of MVP-associated structural abnormalities.

Abstract 4138007: Mechanisms of Mitral Regurgitation in Fabry Disease

Introduction: Fabry disease, caused by mutations in the gene encoding alpha-galactosidase A, results in the accumulation of globotriaosylceramide (Gb3), leading to systemic complications including cardiac involvement such as mitral regurgitation (MR). The aim of this study is to investigate the association between MR severity and mitral leaflet morphology in Fabry disease patients. A cohort of 38 symptomatic Fabry disease patients with moderate or significant MR was followed up. Mitral leaflet morphology was categorized as normal, fibrodegenerative changes, or leaflet thickening. MR severity varied, with the primary cause being leaflet restriction. Additionally, left ventricular outflow tract obstruction (LVOTO) and annular dilatation were observed. The study suggests that MR in Fabry disease is primarily due to leaflet restriction, either through degenerative changes or leaflet thickening. This study investigates the association between MR severity and mitral leaflet morphology in Fabry disease patients. Methods: A cohort of 38 symptomatic Fabry disease patients with moderate or significant MR was followed up. Echocardiographic assessments were conducted to determine MR severity and categorize mitral leaflet morphology. Statistical analyses were performed to evaluate associations between MR severity and leaflet morphology. Echocardiographic assessments of the mitral valve were conducted using a Vivid E95 Cardiac Ultrasound and meticulously analyzed using the EchoPAC TM and TOMTEC Imaging Systems. A crucial aspect of the examination involved measuring all components of the mitral valve and determining the requisite angles to evaluate each mechanism thoroughly. Results: Most patients exhibited leaflet restriction as the primary cause of MR, with varying degrees of severity. Mitral leaflet morphology was categorized as normal in 15,8%, fibrodegenerative changes were in 31,5% and leaflet thickening in 52,7%. In addition, outflow tract obstruction (LVOTO) was observed in 15,7% but without systolic anterior motion (SAM) and annular dilatation (dilatation of anteroposterior annulus more than 35 mm in systole) was present in 66%. Conclusion: The study suggests that MR in Fabry disease is primarily attributed to leaflet restriction, either due to degenerative changes or leaflet thickening. An additional, albeit not unexpected, finding not always considered is the presence of anteroposterior annular dilatation in some cases.

Abstract 4138545: Mitral Valve Replacement is associated with favourable Functional and Clinical Outcome as compared with Restrictive Mitral Annuloplasty in Patients with Severe Ischemic Mitral Regurgitation. A prospective longitudinal analysis

Background: Restrictive mitral annuloplasty (RMA) and chordal-sparing mitral valve replacement (MVR) are common options for treatment of chronic severe ischemic mitral regurgitation. Research question: in patients with severe ischemic mitral regurgitation the most effective surgical approach remains controversial Aim: to test whether MVR provides superior clinical and functional outcomes compared with RMA. Methods: a prospective longitudinal analysis on 187 patients (age: 66 ± 9 year; EF:35 ± 8 %) undergoing MVR or RMA and CABG for severe ischemic mitral regurgitation. Six-minute walking test and echocardiography were performed at preoperative baseline, at 1 year and at a median FU of 5 year (interquartile range: 2.9). Brain natriuretic peptide levels were also obtained. Mitral regurgitation was defined through a comprehensive and integrative approach. Recurrent mitral regurgitation was defined as a vena contracta ≥ 3 mm at follow-up, in patients with no persistent regurgitation at discharge. The primary outcome was a 5-year composite of all-cause mortality and rehospitalization for heart failure. Survival analysis was performed with Kaplan-Meier method. Cox regression analysis was used to verify any independent predictor of composite end-point Results: Baseline preoperative data were similar between the two group. Mitral valve replacement was performed in 49% of patients (n=92) and RMA in 51 % (n=95). At 5 year patients referred to prostheses showed significant improvement in six-minute walking test as compared to RMA (MVR: 290 ± 70 meters vs MRA: 165± 56 meters) (p > 0.01) ( Figure 1 ). The brain natriuretic peptide values did not differ between the two group at 1 year whereas were significantly lower in the MVR group at 5 years (MVR: 135 pg/ml; interquartile range:100 vs RMA: 486 pg/ml; interquartile range: 68 (p<0.01) ( Figure 2 ). At 5 years freedom from all-cause death and rehospitalization for heart failure was higher in the MVR group as compared to RMA (84 ±8.9% vs 61 ±12%, p<0.01) ( Figure 3 ). According to the Cox analysis recurrent mitral regurgitation was found to be a predictor of clinical outcome (HR:5.4, 95% CI:1.3-23.2, p= 0.023). Conclusions: In patients with severe ischemic mitral regurgitation referred for surgery, chordal- sparing MVR and CABG may improve functional capacity, clinical outcome and brain natriuretic peptide levels, compared with RMA and CABG. The impact of these findings remains to be defined by larger studies on longer term

Abstract 4119517: Association of Systemic Inflammatory Response Syndrome with Cardiovascular Events after Mitral Transcatheter Edge-to-edge Repair

Background: Systemic inflammatory response syndrome (SIRS) following cardiovascular interventions is associated with adverse events during hospitalization and follow-up. Mitral transcatheter edge-to-edge repair (M-TEER) is increasingly utilized for treatment of mitral regurgitation (MR). Hypothesis: It is unknown whether SIRS following M-TEER may occur and be associated with adverse clinical outcomes. Goals: to investigate the frequency and impact of SIRS following M-TEER on major cardiovascular events (MACE) and MR recurrence. Methods: A total of 158 consecutive patients with severe MR undergoing M-TEER were studied. SIRS was defined by leukocytosis (≥12×10 9 /L) and fever (T≥38 °C) within 48 hours after intervention. Baseline inflammation was measured by absolute neutrophil and lymphocyte counts and neutrophil: lymphocyte ratio (NLR). The primary endpoint of MACE was the composite of non-fatal myocardial infarction (MI), non-fatal stroke, and all-cause death. Recurrent MR at follow-up was also recorded. Results: The mean patient age was 80.8±8.8 years. 44 (27.9%) developed SIRS. NLR correlated with onset of leukocytosis and fever (p=0.04). During a median follow-up of 12.5±8.2 months, the primary endpoint occurred in 27 (17.1%) patients (6 MI, 5 strokes and 16 deaths). Patients with SIRS more often had severe MR (79.5% vs. 62.7%, p=0.02) and adverse left ventricular (LV) remodeling indicated by lack of reduction in end-diastolic diameter (LVEDD) at follow-up (p=0.12 for SIRS-patients vs. p=0.0012 for non-SIRS patients). After adjustment for pertinent variables, SIRS (HR 3.24, CI 1.13-9.31, p=0.03) was independently associated with MACE. Conclusion: SIRS after M-TEER is a strong independent predictor of MACE. Closer follow-up is warranted as patients with SIRS have more severe MR and unfavorable LV remodeling at follow-up.

Abstract 4144585: Association of renal function with mortality and heart failure hospitalization rates after Transcatheter Mitral Valve Edge to Edge Repair

Background: Transcatheter edge to edge repair (TEER) is an established treatment for patients with symptomatic severe functional MR on optimal medical therapy or severe symptomatic primary MR and high surgical risk. Renal dysfunction is associated with adverse outcomes but the threshold at which risks rise are uncertain. Aim To determine the association of estimated glomerular filtration rate (eGFR) with adverse outcomes in patients undergoing TEER for severe symptomatic mitral regurgitation (MR) in Ontario, Canada. Methods: This was a population-based retrospective cohort study using linked administrative datasets of patients who underwent TEER in Ontario, Canada, between 2011 and 2023. The key exposure was eGFR, which was modeled using restricted cubic splines. Outcomes were 1-year mortality, cardiovascular mortality (CV) and heart failure hospitalization (HF). Cause-specific hazards regression was used to model the association between eGFR and outcomes, utilizing eGFR 30ml/min/1.73m2 as the reference value. Results: We studied 2076 patients, of whom 294 (14.2%) had eGFR <30ml/min/1.73m2 and 841 (40.5%) had eGFR 30-60ml/min/1.73m2. The incidence at one year was 16.8% for all-cause mortality, 11% for CV mortality and 14.2% for HF hospitalizations. The Figure illustrates that the predicted incidence of adverse outcomes increases with lower eGFR, with subtle differences in patterns of change in risk at lower eGFR levels such that all-cause mortality and CV mortality begin to rise rapidly at eGFR values ≤30ml/min/1.73m2, while HF hospitalization increases linearly at eGFR ≤50ml/min/1.73m2. Conclusions: There was a progressive increase in all-cause, CV mortality and HF hospitalization after TEER for patients with lower eGFR, particularly those with values <30 ml/min/1.73m2. This data can inform patient discussions and guide post-procedural follow-up.

Abstract 4117438: Machine Learning Predicts Successful Transcatheter Mitral Valve Edge to Edge Repair: A Systematic Review and Meta-Analysis

Introduction: Transcatheter Mitral Valve Edge to Edge Repair (TEER) is an established percutaneous treatment for patients with severe symptomatic Mitral Regurgitation (MR). The current AHA/ACC guidelines recommend TEER for inoperable patients with severe primary MR or patients with symptomatic severe secondary MR despite medical therapy. Machine learning (ML) has emerged as a tool for TEER risk stratification due to the paucity of established risk scores. To address the lack of consensus on its efficacy, we conducted a systematic review and meta-analysis of studies that utilized ML to predict the success of TEER. Methods: Electronic databases, including Embase, MEDLINE, and the Cochrane Library, were searched from inception through April 2024. We included studies that used TEER and employed at least one ML model to predict the success of TEER. The Area Under the Receiver Operating Characteristic Curve (AUC) was used to measure the accuracy of ML risk stratification algorithms. Results: 102 publications were screened, with seven eventually included in this analysis. Two studies employed clustering techniques, two utilized extreme gradient boosting, and three used multiple ML algorithms to predict outcomes. Of the four studies that compared the accuracy of ML with traditional Cox regression, all four demonstrated higher accuracy with ML, and this difference was statistically significant in three of the four studies. The mean AUC of the aggregated ML data was 0.737 [95% CI: 0.717, 0.758], compared to 0.627 [95% CI: 0.600, 0.653] for the pooled traditional methods. Conclusions: To our knowledge, we conducted the first systematic review and meta-analysis of ML methods for prediction of TEER success. ML outperformed established risk scores, demonstrating promising potential. Future ML models, trained on larger patient datasets, may further improve predictive accuracy in this patient population.

Abstract 4138282: Effect of cardiopulmonary exercise testing parameters and global longitudinal strain on survival after surgery for severe primary mitral regurgitation

Background: Optimum timing of surgery for severe primary mitral regurgitation (MR) particularly in the absence of significant symptoms or echo evidence of LV impairment remains unclear. Other modalities of assessment include cardiopulmonary exercise testing (CPET) and novel echo measurements, such as LV global longitudinal strain (LVGLS). We sought to evaluate whether pre-op CPET or LVGLS are associated with survival after surgery. Methods: We identified consecutive patients who had surgery for severe primary MR between 2007 and 2017 and had pre-op CPET. Clinical and mortality data were collected from chart review and our institutional database. LVGLS was retrospectively collected by a single person blinded to patient outcomes. Primary outcome was post surgery all cause death, and we used univariable analysis to identify variables associated with all cause death. Results: We included 176 patients with median age 63 (IQR 51, 71) years, 63 patients (35.8%) were female and 31 patients (14.8%) had a history of atrial fibrillation. 165 patients (93.8%) had mitral repair, 18 (10.2%) had concomitant CABG, 22 (12.5%) had concomitant ablation procedure and 14 (8.0%) had concomitant tricuspid procedure. 114 patients (64.8%) were in NYHA Class I and 56 (31.8%) were in NYHA Class II. There was no operative mortality. Median % predicted peak VO2 (ppVO2) was 89 (74, 101), median ventilatory equivalent of carbon dioxide (VE/VCO2) was 28.0 (25.7, 31.0) l/min/l/min and median respiratory exchange ratio was 1.2 (1.1, 1.2). 73 patients (41.5%) had abnormal CPET (defined as ppVO2<85%). Median LVEF was 65 (60, 68) %, median LVESD was 35 (32, 38) mm and median LVGLS was 18.5 (16.6, 20.3) %. 45 patients (25.9%) had abnormal LVEF (defined as ≤ 60%), 11 patients (6.7%) had abnormal LVESD (defined as ≥45mm) and 35 patients (20.8%) had abnormal LVGLS (defined as <16%). At a median follow up of 10.2 (6.8, 13.2) years, there were 19 (10.8%) deaths. In the univariate analysis, age at surgery (HR 1.12, p<0.001), LVESD (HR 1.11, p=0.009), LVGLS (HR 1.11, p=0.013) and VE/VCO2 (HR 1.08, p=0.044) were associated with all cause mortality. Conclusion: A significant proportion of patients with no or mild symptoms exhibit echocardiographic evidence of LV impairment when having surgery for severe primary MR. CPET parameters such as VE/VCO2 and novel echocardiographic measurements such as LVGLS may predict risk of long term mortality and potentially inform timing of surgery in these patients.

Abstract 4138386: Deep Learning-Enabled Assessment of Right Ventricular Function Using 2D Echocardiograms Improves 1-Year Mortality Prediction in Patients with Severe Mitral Regurgitation Undergoing Transcatheter Edge-to-Edge Repair

Background: Right ventricular (RV) function has a well-established prognostic role in patients with severe mitral regurgitation (MR) undergoing transcatheter edge-to-edge repair (TEER) and is typically assessed using echocardiography-measured tricuspid annular plane systolic excursion (TAPSE). Recently, a deep learning model has been proposed that accurately predicts RV ejection fraction (RVEF) from 2D echocardiographic videos, with similar diagnostic accuracy as 3D imaging. Aims: This study aimed to evaluate the prognostic utility of the deep learning-predicted RVEF values in patients with severe MR undergoing TEER. Methods: This multicenter registry study analyzed the associations between the predicted RVEF values and 1-year mortality in patients with severe MR undergoing TEER. To predict RVEF, 2D apical four-chamber view videos from preprocedural transthoracic echocardiographic studies were exported and processed by a rigorously validated deep learning model. Results: From 1,366 patients undergoing TEER between 2017 and 2023, good-quality 2D apical four-chamber view videos could be retrieved for 1,154 patients (84.5%). Survival at one year after TEER was 84.7%. The predicted RVEF values ranged from 26.6% to 64.0% and correlated only modestly with TAPSE (Pearson correlation coefficient R: 0.33; p -value: <0.001). Importantly, predicted RVEF levels were superior to TAPSE levels in predicting 1-year mortality after TEER (area under the curve: 0.687 vs. 0.625; p -value: 0.029). Furthermore, Kaplan-Meier survival analysis revealed that patients with preserved RV function (defined as a predicted RVEF of ≥45%) had significantly better 1-year survival rates than patients with reduced RV function (92.1% [95% CI: 89.5-94.7%] vs. 80.3% [95% CI: 77.4-83.3%], respectively, hazard ratio for 1-year mortality: 2.67, p -value: <0.001). Conclusion: Deep learning-enabled assessment of RV function using standard 2D echocardiographic videos can refine the prognostication of patients with severe MR undergoing TEER. Thus, it can be used to screen for patients with RV dysfunction who might benefit from intensified follow-up care.

Abstract 4129273: Severe Mitral Regurgitation from Impella-associated Mitral Chordae Rupture with Successful Transcatheter Edge-to-edge Repair

Background: Limited data exists describing Impella-related mechanical mitral valve complications. Diagnosis and management can be challenging due to potential underestimation of mitral regurgitation severity from Impella and acute clinical deterioration upon removal. We present a case of successful mitral transcatheter edge-to-edge repair (TEER) for acute severe MR secondary to Impella-related mitral chordae rupture resulting in acute pulmonary edema post-Impella removal. Case Summary: A 37-year-old male smoker presented with chest pain complicated by cardiac arrest due to ventricular fibrillation. Spontaneous circulation could not be restored, requiring veno-arterial extracorporeal membrane oxygenation (VA-ECMO). Coronary angiography revealed total occlusion of the proximal left anterior descending artery, which was successfully stented. Transfemoral Impella CP was placed for left ventricular venting under fluoroscopy (Panel A) with TTE showing no complications. In the intensive care unit, the Impella was advanced under TTE guidance; its tip was found to be positioned deep at the base of the posteromedial pupillary muscle without suction alarms or ventricular arrhythmias on the following day (Panel B). Several days later, TTE revealed new eccentric MR with hyperdynamic left ventricular motion (Panel C). The patient remained hemodynamically stable after VA-ECMO decannulation with Impella at P4. Following Impella removal, he developed repeated flash pulmonary edema despite aggressive fluid removal attributed to acute severe MR secondary to a flail P3 leaflet with ruptured chordae tendineae confirmed by transesophageal echocardiography (Panel D). Given the patient's poor surgical candidacy with a STS score of 13.2%, the team proceeded with mitral TEER, successfully reducing MR severity from severe to mild with a single NT Mitraclip ® across the medial commissure (Panel E). His post-operative cardiac course was uneventful without recurrence of pulmonary edema. Discussion: Irreversible mechanical damage to the mitral valve apparatus caused by Impella placement and repositioning is a rare, potentially fatal complication requiring emergent intervention. Mitral TEER can be a viable salvage option for poor surgical candidates.

Abstract 4125729: Elevated Pre-Procedural Serum Natriuretic Peptide Levels Are Associated with All-Cause Mortality in Patients Undergoing Transcatheter Edge-to-Edge Mitral Valve Repair: A Systematic Review and Meta-Analysis

Background: Transcatheter edge-to-edge mitral valve repair (TEER) is an established procedure in patients with severe mitral regurgitation (MR) and elevated surgical risk on optimal medical therapy. However, there remains considerable mortality in this patient population. Some studies have shown that serum brain natriuretic peptide (BNP) and N-terminal pro b-type natriuretic peptide (NT-proBNP) predict all-cause mortality after TEER, whereas other studies have shown mortality to be independent of these markers. To address this gap in knowledge, we sought to examine the existing literature to determine whether there is an association between pre-procedural serum natriuretic peptides and mortality after TEER. Hypothesis: Among patients undergoing TEER, elevated pre-procedural BNP and NT-proBNP are associated with increased all-cause mortality. Methods: Databases including MEDLINE, Embase, and Cochrane Library were searched from inception through September 2023 for studies assessing pre-procedural serum natriuretic peptide levels and mortality among patients undergoing TEER. Pooled hazard ratios (HR) and standardized mean differences (SMD) were calculated using a random-effects model estimated by restricted maximum likelihood with the Hartung-Knapp modification. Results: A total of 30 studies comprising 10259 patients undergoing TEER met inclusion criteria. 25 studies measured NT-proBNP and 5 studies measured BNP. Elevated pre-procedural NT-proBNP (>5000 or >10000 pg/mL) was associated with increased all-cause mortality in both adjusted (HR = 2.94; 95% CI = 1.75 - 4.95; I2 = 46.8%) and unadjusted (HR = 5.16; 95% CI = 1.85 - 14.40; I2 = 0.0%) analyses (Figures 1 and 2). Pre-procedural BNP and NT-proBNP were also significantly lower among survivors at 12 months compared to non-survivors (SMD = 0.82; 95% CI = 0.37 - 1.27; I2 = 78.3%) (Figure 3). This association was demonstrated in patients with primary or secondary MR. Conclusions: Pre-procedural BNP and NT-proBNP levels are significant predictors of all-cause mortality in patients undergoing TEER for primary or secondary MR. This supports the inclusion of BNP or NT-proBNP in pre-procedural assessments to help inform patient discussions and guide post-procedural follow-up and monitoring.

Abstract 4138268: The Use of Mavacamten for Management of Post TAVR Obstruction: A Novel Approach to Treatment

Background: Treatment of left ventricular outflow tract (LVOT) obstruction involves a combination of negative inotropic agents. However, these therapies have limitations which may result in insufficient control of symptoms, leading to more invasive options such as surgical septal myectomy or septal alcohol ablation. Mavacamten, a cardiac myosin inhibitor, is currently approved for the treatment of patients with symptomatic obstructive hypertrophic cardiomyopathy (HCM). We present a case of a patient treated with mavacamten in addition to β-blockers (BB) for management of post-TAVR LVOT obstruction. Case: A 76 year old female with a past medical history of hypertension, severe aortic stenosis, and coronary artery disease underwent a Medtronic Evolut TAVR in March 2022. Her TTE post TAVR showed LVOT peak gradient greater than 100 mm Hg, LVEF 75% and severe eccentric mitral regurgitation secondary to systolic anterior motion (SAM) of the mitral valve (MV). After multidisciplinary discussion, the patient was discharged on maximally tolerated BB therapy. Follow up TTE showed persistent obstruction and gradients, so diltiazem was added to her regimen. Her subsequent TTE showed a peak LVOT > 100 mmHg at rest, and severe MR. Given persistent findings, she was started on mavacamten, continued on metoprolol, and tapered off of diltiazem. Her TTE two months after initiation of mavacamten revealed resolution of LVOT gradients, reduction of MR to mild and normal LV and TAVR function. She tolerated the therapy well and endorsed ongoing symptomatic improvement on subsequent follow up. Discussion: With the increasing use of TAVR therapy, there has been a corresponding rise in cases of post-TAVR obstruction that must be managed. As demonstrated by this case, management with BB therapy alone may be suboptimal. Although mavacamten is currently approved in patients with HCM, the obstruction in post-TAVR patients is functionally similar. Thus, this medication was trialed as a supplemental treatment in this patient and yielded positive results. This case highlights the potential benefit of extending use of mavacamten alongside β-blocker therapy for this patient population and suggests the need for future studies.

Thoracoscopic hypothermic fibrillatory arrest mitral valve replacement for severe mitral regurgitation in Marfan syndrome after Bentall procedure.

Thoracoscopic hypothermic fibrillatory arrest mitral valve replacement for severe mitral regurgitation in Marfan syndrome after Bentall procedure.

Abstract 4144514: Human Immunodeficiency Virus Associated Cardiomyopathy- A Rare Cause of Heart Failure With Reduced Ejection Fraction in Era of Highly Active Antiretroviral Therapy

Introduction: Human Immunodeficiency Virus Associated Cardiomyopathy (HIVAC) is characterized by left ventricular (LV) systolic or diastolic dysfunction with or without LV dilatation and heart failure symptoms. The introduction of antiretroviral therapy (ART) has changed the fulminant systolic heart failure presentation of HIV myocarditis to diastolic heart failure. We present a unique case of dilated cardiomyopathy in a young patient without advanced HIV illness which has rarely been documented in the literature. This is a rare presentation of HIVAC in the post-ART era. Case Report: A 32-year-old male with a past medical history (PMH) of the human immunodeficiency virus (HIV) presented with complaints of new onset worsening shortness of breath and lower extremity edema for four weeks. He was diagnosed with HIV seven years ago and was not compliant with ART. Laboratory testing showed a cluster of differentiation 4 (CD4) 823 and HIV load 2550. Myocarditis was ruled out by normal troponin levels and no new changes on the electrocardiogram (ECG). Transthoracic echocardiogram (TTE) showed dilated left ventricle (LV), LV global hypokinesis, LV ejection fraction (LVEF) 10-15%, dilated right ventricle, biatrial dilation, moderate to severe mitral regurgitation, severe tricuspid regurgitation, pulmonary artery (PA) systolic pressure 73 mmHg and no pericardial effusion. Coronary angiography was negative for coronary artery disease (CAD). The patient was started on carvedilol and outpatient evaluation for a left ventricular assistance device. Discussion: Systolic dysfunction in patients with HIVAC carried a poor prognosis in the pre-ART era and was common in patients with elevated c-reactive protein (CRP), tobacco use, and previous myocardial infarction (MI). After the advent of ART, systolic dysfunction is rare and replaced by diastolic cardiomyopathy in the setting of ART use. Diagnosis is usually by excluding other etiologies and biopsy is not necessarily required. Management is usually guideline-directed medical therapy (i.e. beta blocker, renin-angiotensin-aldosterone antagonists, sodium-glucose cotransporter-2) and device-based therapy but there is still data lacking to assess its benefit.

Association of Systemic Inflammatory Response Syndrome With Cardiovascular Events After Mitral Transcatheter Edge-to-Edge Repair.

Systemic inflammatory response syndrome (SIRS) following cardiovascular interventions is associated with adverse events during hospitalization and follow-up. Mitral transcatheter edge-to-edge repair is increasingly utilized for treatment of mitral regurgitation (MR). We investigated whether SIRS following mitral transcatheter edge-to-edge repair may occur and be associated with adverse clinical outcomes. A total of 158 consecutive patients with severe MR undergoing mitral transcatheter edge-to-edge repair were studied. SIRS was defined by leukocytosis (≥12 × 109/L) and fever (≥38 °C) within 48 hours after intervention. Baseline inflammation was measured by absolute neutrophil and lymphocyte counts and neutrophil-lymphocyte ratio. The primary end point of major cardiovascular events was the composite of nonfatal myocardial infarction, nonfatal stroke, and all-cause death. Recurrent MR at follow-up was also recorded. The mean patient age was 80.8±8.8 years. Forty-four (27.9%) developed SIRS. Neutrophil-lymphocyte ratio correlated with onset of leukocytosis and fever (P=0.04). During a median follow-up of 12.5 (5.4-17.4) months, the primary end point occurred in 27 (17.1%) patients (6 myocardial infarction, 5 strokes, and 16 deaths). Patients with SIRS more often had severe MR (79.5% versus 62.7%, P=0.02) at follow-up. After adjustment for pertinent variables, SIRS (HR 2.73 [95% CI, 1.08-6.86]; P=0.03) was independently associated with major cardiovascular events. SIRS after mitral transcatheter edge-to-edge repair is a strong independent predictor of major cardiovascular events. Closer follow-up is warranted because patients with SIRS have more severe MR at follow-up.

Preoperative Predictors of Recurrent Tricuspid Regurgitation After Annuloplasty: Insights into the Role of 3D Echocardiography

Background: While tricuspid annuloplasty (TAP) is an effective treatment option for tricuspid regurgitation (TR), understanding the echocardiographic factors contributing to recurrent TR can help in developing more effective preventive measures to reduce the rate of recurrent TR after TAP. Methods: This study was designed as a prospective observational cohort study to investigate factors contributing to recurrent TR following surgical tricuspid valve (TV) repair in patients with moderate or severe functional TR caused by left heart valvular disease, with severe mitral regurgitation as the dominant pathology. The study included 66 patients who underwent preoperative two-dimensional (2D) and three-dimensional (3D) echocardiographic assessments. Patients were divided into two groups based on TAP outcomes: the effective TAP group and the recurrent TR group. Results: The analysis revealed that 3D-derived both septal–lateral diastolic and systolic tricuspid annulus (TA) diameter (odds ratio (OR) 1.77; 95% confidence interval (CI) 1.17–2.68 and OR 1.62; 95% CI 1.14–2.29, respectively), and major axis diastolic TA diameter (OR 1.59; 95% CI 1.15–2.2) had the highest OR among all echocardiographic parameters. The further univariate analysis of predefined echocardiographic values unveiled that the combined effect of heightened 3D-measured TA major axis diastolic diameter and increased right ventricle (RV) basal diameter exhibited the highest OR at 12.8 (95% CI 2.3–72.8) for a recurrent TR. Using ROC analysis, diastolic major axis (area under the curve (AUC) 0.848; cut-off 48.5 mm), septal-lateral systolic (AUC 0.840; cut-off 43.5 mm) and diastolic (AUC 0.840; cut-off 46.5 mm) TA diameter demonstrated the highest predictive value for recurrent TR from all TV parameters. Conclusions: Recurrent moderate or severe TR after TAP is associated with preoperative TA size, right atrium and RV geometry, but not with changes of RV function. The predictive capacity of 2D-assessed echocardiographic parameters was found to be lower when compared to their corresponding 3D parameters.

Automatic Segmentation and Evaluation of Mitral Regurgitation Using Doppler Echocardiographic Images

Background: Mitral Regurgitation (MR) is a common heart valve disease. Severe MR can lead to pulmonary hypertension, cardiac arrhythmia, and even death. Therefore, early diagnosis and assessment of MR severity are crucial. In this study, we propose a deep learning-based method for segmenting MR regions, aiming to improve the efficiency of MR severity classification and diagnosis. Methods: We enhanced the Efficient Multi-Scale Attention (EMA) module to capture multi-scale features more effectively, thereby improving its segmentation performance on MR regions, which vary widely in size. A total of 367 color Doppler echocardiography images were acquired, with 293 images used for model training and 74 images for testing. To fully validate the capability of the improved EMA module, we use ResUNet as the backbone, partially integrating the enhanced EMA module into the decoder’s upsampling process. The proposed model is then compared with classic models like Deeplabv3+ and PSPNet, as well as UNet, ResUNet, ResUNet with the original EMA module added, and UNet with the improved EMA module added. Results: The experimental results demonstrate that the model proposed in this study achieved the best performance for the segmentation of the MR region on the test dataset: Jaccard (84.37%), MPA (92.39%), Recall (90.91%), and Precision (91.9%). In addition, the classification of MR severity based on the segmentation mask generated by our proposed model also achieved acceptable performance: Accuracy (95.27%), Precision (88.52%), Recall (91.13%), and F1-score (90.30%). Conclusion: The model proposed in this study achieved accurate segmentation of MR regions, and based on its segmentation mask, automatic and accurate assessment of MR severity can be realized, potentially assisting radiologists and cardiologists in making decisions about MR.

Impella 5.5 as a bridge-to-surgery in acute ischemic mitral regurgitation post-percutaneous coronary intervention: a case report

BackgroundAcute ischemic mitral regurgitation (AIMR) is a significant complication of acute coronary syndrome that leads to severe and immediate hemodynamic deterioration and cardiogenic shock. Intra-aortic balloon pumps (IABP) are commonly used to support patients with AIMR as a bridge to surgery, though they may be insufficient in some cases.Case PresentationA 74-year-old male presented with two days of indigestion and evident hypoxia, and an electrocardiogram revealed inferior and lateral ST-elevation myocardial infarction. Angiography demonstrated severe two-vessel coronary disease with a 100% thrombotic occlusion of the second obtuse marginal artery (OM2, culprit lesion) and an 80% stenosis of the proximal left anterior descending artery (LAD). Despite stenting of OM2, the patient remained hypoxic and hypotensive, necessitating escalated support via an IABP. A follow-up echocardiogram revealed severe mitral regurgitation presumed to be AIMR secondary to a ruptured posteromedial papillary muscle with a flail anterior leaflet (A2). Despite aggressive supportive measures with the IABP, the patient’s hemodynamics continued to show cardiogenic shock and clinical status did not improve. However, the patient was required to abstain from surgery for a P2Y12 inhibitor therapy wash out period. Consequently, the IABP was upgraded to Impella 5.5 as bridge-to-surgery support on day 1 post-admission. Subsequently, the patient’s hemodynamics improved, and he underwent a combined mitral valve replacement and coronary artery bypass grafting surgery on day 7 post-admission without incident. The Impella was successfully explanted on day 25 post-admission. Delay in explant was due to hypotension and respiratory status despite normalizing hemodynamics and echocardiogram revealing recovered left ventricular ejection fraction. The patient developed bacterial pneumonia and acute respiratory distress syndrome and expired on day 27 post-admission.ConclusionAlthough IABP is standard for supporting AIMR patients as a bridge to surgery, it may not provide sufficient hemodynamic support. This case supports a growing body of evidence that alternative forms of hemodynamic support should be considered if the traditional therapeutic modalities for AIMR do not adequately support patients. Clinicians may consider upgrading IABP to Impella to provide increased hemodynamic support and maintain AIMR patient stability while awaiting cardiac surgery.

Disparities in quantification of mitral valve regurgitation between cardiovascular magnetic resonance imaging and trans-thoracic echocardiography: a systematic review.

Primary mitral regurgitation (MR) is a prevalent valvular heart disease. Therapy stratification for MR depends on accurate assessment of MR severity and left ventricular (LV) dimensions. While trans-thoracic echocardiography (TTE) has been the standard/preferred assessment method, cardiovascular magnetic resonance imaging (CMR) has gained recognition for its superior assessment of LV dimensions and MR severity. Both imaging modalities have their own advantages and limitation for therapy guidance. However, the differences between the two modalities for assessing/grade severity and clinical impact of MR remains unclear. This systematic review aims to evaluate the differences between TTE and CMR in quantifying MR severity and LV dimensions, providing insights for optimal clinical management. A literature search was performed from inception up to March 21st 2023. This resulted in 2,728 articles. After screening, 22 articles were deemed eligible for inclusion in the meta-analysis. The included study variables were, mitral valve regurgitation volume (MRVOL), regurgitation fraction (MRFRAC), LV end-diastolic volume (LVEDV), LV end-systolic volume (LVESV), LV stroke volume (LVSV), and LV ejection fraction (LVEF). TTE showed a significant higher MRVOL (10.4ml, I2 = 88%, p = 0.002) and MRFRAC (6.3%, I2 = 51%, p = 0.05) compared to CMR, while CMR demonstrated a higher LVEDV (21.9ml, I2 = 66%, p = < 0.001) and LVESV (16.8ml, I2 = 0%, p = < 0.001) compared to TTE. Our findings demonstrate substantial disparities in TTE and CMR derived measurements for parameters that play a pivotal role in the clinical stratification guidelines. This discrepancy prompts a critical question regarding the prognostic value of both imaging modalities, which warrants future research.

Accidental finding of ALCAPA in a child with severe mitral regurgitation: A case study.

A six-year-old child who had undergone cardiac surgery five years ago presented to us with severe mitral valve regurgitation. During her current surgery, the coronary artery was injured during the attempt to release extensive epicardial adhesion, resulting in very poor contractility that prompted a delay in the intended valve repair. The injured coronary vessels were successfully repaired, yet low cardiac output syndrome persisted during perioperative care, necessitating further investigation of the coronary problem. It was later discovered that the patient had anomalous left coronary artery from pulmonary artery (ALCAPA) syndrome. The presence of severe mitral regurgitation, pulmonary hypertension, and anatomical factors may have contributed to the delayed presentation and diagnosis in this case. The severity of mitral regurgitation and the most likely underlying mechanism indicates a low possibility of recovery following coronary repair alone, warranting the need for concomitant mitral surgery. Coronary and mitral repair were performed in this patient, resulting in a favorable outcome. The management of ALCAPA presents unique challenges, especially in cases with delayed diagnosis. Proper diagnosis and tailored surgical approaches are crucial for achieving favorable outcomes in patients with ALCAPA.