Mitral Regurgitation Research Articles

The Modified History of Juvenile Rheumatic Mitral Stenosis Following Percutaneous Transmitral Commissurotomy: Intermediate-Term Outcomes From a Decadal Follow-Up Study

There are few studies that have looked at the long-term outcomes of juvenile mitral stenosis (JMS) following percutaneous transmitral commissurotomy (PTMC). This study sought to analyse the modified history of JMS in children following PTMC. We describe a longitudinal, observational follow-up study of all children and young adults aged <20 years who underwent PTMC at Sri Jayadeva Institute of Cardiovascular Sciences and Research, Bangalore, India from 2012 to 2021. Children were followed up for progression of mitral stenosis (MS), development of mitral regurgitation (MR), need for repeat interventions (percutaneous or surgical), and mortality. A total of 114 children and adolescents underwent the procedure. The mean age of children in the study was 15.1±2.5 years. After immediate procedural success, there was a tendency towards restenosis with respect to valve areas and transmitral gradients at follow-up. Severe MR after the procedure was noted in 2.6%. Compliance with penicillin prophylaxis was noted in 42.5%. The Kaplan-Meier survival estimate over 10 years showed a mortality rate of 1.98/100 patient-years and a re-intervention rate (re-do PTMC or surgery) of 5.50/100 patient-years. Additional valvular lesions were noted in 13.1% of children during follow-up. Severe symptomatic status at presentation (New York Heart Association class 4) was predictive of mortality, and children aged <15 years often needed re-intervention. With a mortality rate of 6.1% and re-do intervention rate of 15.8% during extended follow-up, JMS has considerable healthcare implications in terms of morbidity and mortality in children and young adults.

Assessment of Myocardial Fibrosis in Marfan Syndrome Using Cardiac Magnetic Resonance Imaging.

Impaired myocardial function and arrhythmia are important manifestations of Marfan syndrome (MFS). Studies assessing myocardial fibrosis in relation to these manifestations are scarce. This cross-sectional, single-center study assessed ventricular volumes, ventricular function, and myocardial fibrosis by cardiac magnetic resonance imaging (CMR) in patients with MFS harboring a (likely) pathogenic FBN1 variant. The presence and extent of fibrosis were assessed by late gadolinium enhancement (LGE) and extracellular volume measurement (ECV). Data on 24-h Holter monitoring and clinical data were extracted from electronic patient records. The study included 32 unselected patients with MFS (median age 38 years [range 10-69], 41% women). No focal myocardial fibrosis was detected. Six patients (21%) had diffuse fibrosis (ECV > 29%). No association was found between the presence of diffuse fibrosis and clinically relevant myocardial dysfunction. Five patients (16%) had reduced left ventricular ejection fraction (LVEF < 55%). While all of these exhibited mitral annular disjunction (MAD), only two had ECV > 29%. Patients with MAD had increased indexed LV volumes (median end-diastolic volume, 92 mL/m2 [IQR, 78-100] vs. 78 mL/m2 [IQR, 71-87]; median end-systolic volume, 31 mL/m2 [IQR, 23-46] vs. 22 mL/m2 [IQR, 21-28]), also after adjusting for the presence of mitral and aortic valve regurgitation. No differences in ECV were seen between patients with and without MAD. In this cohort of patients with MFS, focal myocardial fibrosis was not detected using CMR. Although diffuse fibrosis was observed in 21% of patients, no evident connection to clinically relevant myocardial dysfunction was found. Further studies should evaluate the impact of diffuse fibrosis on clinical outcome prediction.

Assessing the use of blood microRNA expression patterns for predictive diagnosis of myxomatous mitral valve disease in dogs

Assessing the use of blood microRNA expression patterns for predictive diagnosis of myxomatous mitral valve disease in dogs

Preoperative left atrial size and functions are predictors of left atrial reverse remodelling after mitral valvuloplasty for myxomatous mitral valve disease in dogs

ObjectivesThe objective of this study was to determine alterations in left atrial size, function, and determinants of left atrial reverse remodelling (LARR) after mitral valvuloplasty (MVP) in dogs with myxomatous mitral valve disease (MMVD). AnimalsThirty-seven dogs undergoing MVP. Materials and MethodsEchocardiographic parameters, including left atrial (LA) strain, were evaluated at baseline, during the early postoperative period (within two weeks), and at one and three months postoperatively. Patients were divided into two groups based on the attainment of LARR, defined as a left atrial to aortic root ratio (LA:Ao) < 1.6 at three months. The predictors of LARR were analysed using univariate logistic regression analysis. ResultsLA:Ao significantly decreased in the early postoperative period (median 1.68; lower and upper quartile 1.54–1.92) compared to baseline (2.41; 2.00–2.80), with a further significant reduction observed at three months (1.46; 1.34–1.63). LARR was achieved in 27 (73%) patients. Baseline LA:Ao was higher, and peak atrial longitudinal strain (PALS) and peak atrial construction strain (PACS) were lower in the non-LARR group than in the LARR group. Among the baseline parameters, PACS was the strongest predictor of LARR (area under the curve, 0.837). ConclusionsFollowing MVP, the LA size decreased in the early postoperative period and continued to decrease over three months of follow-up. A low PACS score was the most reliable predictor of inadequate LARR. Further studies are necessary to determine the relationship between LARR, prognosis, and the optimal timing for surgical intervention.

Myxomatous mitral valve disease in Labrador Retrievers and Golden Retrievers.

To characterize myxomatous mitral valve disease (MMVD) in Labrador Retrievers (LRs) and Golden Retrievers (GRs). 52 LRs and 20 GRs diagnosed with MMVD composed a retrospective study sample (February 1, 2010, to July 31, 2021). Stored echocardiograms were remeasured. Dogs were staged by 2019 MMVD consensus guidelines. Mean age was 9.9 years in LRs and 9.5 years in GRs, with 31 of 52 LRs (59.6%) and 13 of 20 (65.0%) GRs being male. Forty-six LRs were stage B1 (88.5%), 3 were B2 (5.8%), and 3 were C (5.8%). Fourteen GRs were stage B1 (70.0%), 2 were B2 (10.0%), and 4 were C (20.0%). Of LRs and GRs in stage B2/C, 50% had systolic dysfunction. Atrial fibrillation (AF) and ventricular arrhythmias were identified in 2 of 52 (3.8%) and 10 of 52 (19.2%) LRs at initial diagnosis versus 3 of 20 (15.0%) and 3 of 20 (15.0%) GRs, respectively. All 5 AF dogs were stage C, with intermediate to high probability of pulmonary hypertension. Two additional GRs developed AF during follow-up; thus 5 of 6 (83.3%) stage B2/C GRs ultimately experienced AF. Subjective mitral valve thickening was frequent in both breeds (41/52 LRs [78.8%]; 18/20 GRs [90.0%]), while mitral valve prolapse was more common in LRs (22/52 [42.3%]) than GRs (5/20 [25.0%]). In LRs and GRs, MMVD was relatively late onset, with males overrepresented. Both breeds exhibited mitral valve thickening in association with MMVD, while LRs more commonly exhibited mitral valve prolapse. While most LRs and GRs with MMVD were stage B1, those in stage B2/C had increased prevalence of systolic dysfunction and AF.

Commentator Discussion: Durability of annuloplasty in patients with atrial functional mitral regurgitation associated with atrial fibrillation

Commentator Discussion: Durability of annuloplasty in patients with atrial functional mitral regurgitation associated with atrial fibrillation

Cutting-Edge Echocardiographic Tools for Enhanced Understanding and Management of Atrial Functional Mitral Regurgitation.

Cutting-Edge Echocardiographic Tools for Enhanced Understanding and Management of Atrial Functional Mitral Regurgitation.

Transesophageal Echocardiography Guidance during Transcatheter Mitral Valve Edge-to-Edge Repair for Severe Mitral Regurgitation Post–Mitral Annuloplasty: A Case Series

Transesophageal Echocardiography Guidance during Transcatheter Mitral Valve Edge-to-Edge Repair for Severe Mitral Regurgitation Post–Mitral Annuloplasty: A Case Series

Effects of boundary conditions on the transmitral pressure gradient for numerical simulation of flow in a left heart model

The transmitral pressure gradient is a crucial clinical indicator for diagnosing mitral regurgitation and stenosis. Numerical simulation of specific patients can obtain the complete pressure distribution in the left heart system, which is an important approach to evaluate cardiac function. However, the results are sensitive to the boundary conditions used in the numerical simulations. In the present work, we constructed a left heart model and assessed the effects of four typical boundary conditions on the transmitral pressure gradient, which is computed based on the Bernoulli equation and the line probe, respectively. The results show that the transmitral pressure gradient obtained by the line probe is sensitive to the boundary conditions. The sensitivity is closely related to the pressure in the atrium but has negligible effect on the pressure in the ventricle. This study sheds light on evaluating the pressure gradient of patient-specific treatments based on the numerical simulation of a left heart model.

An Assessment of Thoracic Inlet Heart Score in Maltese Dogs with ACVIM Stage B Myxomatous Mitral Valve Disease

An Assessment of Thoracic Inlet Heart Score in Maltese Dogs with ACVIM Stage B Myxomatous Mitral Valve Disease

Heart Rate and Rhythm Changes in Dogs Treated in a Hyperbaric Oxygen Chamber

In veterinary medicine, hyperbaric oxygen chamber treatment (HBOT) is gaining popularity. Therefore, an increasing number of patients referred for this therapy are being recorded, mainly due to ischemic events, wound healing support, and a high risk of reperfusion damage. During the HBOT procedure, several changes occur in the body’s micro- and macroenvironments. This study involved 34 dogs of various ages and health statuses. The atmospheric conditions in the test hyperbaric chamber included a pressure of 1.5 atmosphere absolute (ATA) at 100% oxygenation. The individuals were divided into three groups: (1) individuals with degenerative mitral valve disease (DMVD), (2) individuals with diseases other than cardiac issues, and (3) healthy individuals who qualified for the HBOT procedure. The period of measurement using the Holter apparatus was divided into four stages: 30 min before the subject’s placement in the hyperbaric chamber; a 4-min compression period (setting chamber conditions); a 90 min HBOT period; and a 1 min decompression period of the hyperbaric chamber. During the HBOT, there was a statistically significant decrease in heart rate in groups 2 and 3 compared to group 1. The heart rate in group 1 remained unchanged through every period of the study. In addition, some of the dogs developed respiratory arrhythmia; in two dogs, premature ventricle beats occurred. The changes observed during the ventricular period indicate that the HBOT procedure causes a significant change in heart rate in dogs without cardiac diseases.

Classification of primary mitral regurgitation using extramitral cardiac involvement in patients undergoing transcatheter edge-to-edge repair.

An enhanced classification of primary mitral regurgitation (PMR) based on extramitral cardiac involvement may refine patient selection and optimize the timing of transcatheter edge-to-edge repair (TEER). This study aimed to assess the prognostic significance of a recently established classification system that characterizes the extent of extramitral cardiac damage in patients undergoing TEER for PMR. Consecutive PMR patients who received MitraClip implantation were categorized according to the presence of extramitral cardiac damage, determined through preprocedural echocardiography. The classifications included no damage or only left ventricular dilatation (group 0), left atrial involvement (group 1), right ventricular volume/pressure overload (group 2), right ventricular failure (group 3), or left ventricular failure (group 4). Cox-proportional hazard models were used to ascertain the impact of PMR groups on the primary composite outcome of all-cause mortality or rehospitalization for heart failure (HHF) over 2 years. In a cohort of 322 eligible PMR patients undergoing TEER (median age: 83 years; 41% female) between 2013 and 2020, the following distribution emerged: group 0 (10 patients, 3%), group 1 (96 patients, 30%), group 2 (117 patients, 36%), group 3 (56 patients, 18%), and group 4 (43 patients, 13%). Kaplan-Meier analysis demonstrated a significant decline in freedom from the primary outcome as group severity increased (log-rank p = 0.030). On multivariate analysis, the degree of extramitral cardiac involvement was significantly associated with the primary outcome (HR: 1.30; 95% CI: 1.02-1.67; p = 0.043), primarily driven by HHF. This innovative classification system for PMR, based on extramitral cardiac involvement, carries significant prognostic implications for clinical outcomes following TEER. Integrating this classification system into clinical decision-making could enhance risk stratification and optimize the timing of TEER in these patients.

Successful Anaesthetic Management of Triple Valve Surgery (Double Valve Replacement and Tricuspid Valve Ring Repair)- Challenges and Troubleshooting

Heart valve diseases are extensive and include double (mitral-aortic, mitral-tricuspid), or triple (mitral, aortic, and tricuspid) valvular regurgitation, stenotic or mixed lesions. The surgical correction of valvular lesions usually consists of the repair or replacement of all valves affected by a pathologic process.We present a challenging complex valvular case of a 61 year old hypothyroid female diagnosed with severe mitral stenosis with moderate mitral regurgitation, severe aortic stenosis with mild aortic regurgitation and severe tricuspid regurgitation with high pulmonary artery pressures.She successfully underwent Double valve replacement (Mitral and aortic) and Tricuspid Annuloplasty Ring repair.

LEFT VENTRICULAR NON COMPACTION CARDIOMYOPATHY ASSOCIATED WITH MITRAL VALVE PROLAPSE

Left ventricular non compaction (LVNC) is a rare condition characterized by prominent ventricular trabeculations and intertrabecular recesses,Mitral regurgitationwhen present is usually a result of annular dilation, mitral valve prolapse due to chordae tendinae rupture is quite rare.We present the case of a 48 year old male with no medical history who presented with worsening exertional dyspnea classified as NYHA class III. The physical examination found a systolic murmur heard at the apex. Transthoracic echocardiography and cardiac magnetic resonance confirmed the diagnosis of Left ventricular non compaction associated with posterior mitral valve prolapse with severe mitral regurgitation and preserved ventricular function who was successfully operated and found asymptomatic during the follow up.

Evaluating Impact of Surgical Myocardial Revascularization on Global Left Ventricular Systolic Function and Immediate Postoperative Outcome using Transesophageal Echocardiography

Abstract Background and Aims: Surgical myocardial revascularization is supposed to improve the global left ventricular (LV) function by improving the blood supply in significantly occluded coronary arteries. Transesophageal echocardiography (TEE) provides an excellent opportunity to evaluate cardiac function in operating room. Present study was aimed at evaluating impact of surgical myocardial revascularization on global LV systolic function. Comparison of LV fractional shortening (LV-FS), fractional area change (LV-FAC), ejection fraction (LV-EF), indexed LV volumes (indexed LV volumes at end diastole, LV volumes at end systole) and “Tei” (Myocardial performance) index obtained prior and after surgical myocardial revascularization was done for quantitative analysis. Also, the determinants of immediate postoperative outcome were evaluated based on need of pharmacological and/or mechanical cardiovascular support, mechanical ventilation, intensive care unit (ICU) stay, morbidity and mortality in immediate postoperative period. These outcome measures were correlated with baseline values of TEE derived echo indices. Methods: One hundred and ten subjects with significant coronary artery disease scheduled for elective myocardial revascularization surgery. Fourteen subjects were excluded due to presence of either hemodynamic instability requiring either pharmacological or mechanical cardiovascular support, before coronary revascularization (n = 6), presence of Grade III mitral regurgitation (MR) in baseline TEE (n = 2) and arrythmias (n = 6). Ninety six subjects were evaluated for global LV systolic function using TEE before and after surgical revascularization. Subjects were followed in ICU for the outcome. Immediate postoperative outcome was measured as “good” or “poor” based on vasoactive inotropic score, requirement of Intra-aortic balloon counter pulsation (IABP) and mechanical cardiovascular support (VA-ECMO) to maintain cardiac output, duration of mechanical ventilation, postoperative ICU stay, morbidity and mortality. Results: In 96 subjects analyzed, there was a significant improvement in TEE derived LV-FS (38.60 ± 16.38 vs. 31.31 ± 13.14) (P = 0.002), FAC (51.94 ± 16.06 vs. 43.99 ± 16.02) (P ≤ 0.001), EF (53.08 ± 9.97 vs. 46.71 ± 7.53) (P &lt; 0.00001), LV end diastolic volume index (34.84 ± 13.43 vs. 40.08 ± 17.22) (P = 0.0188) and “Tei” index (0.47 ± 0.13 vs. 0.53 ± 0.13) (P = 0.0007). Thirty three subjects required either prolonged stay in ICU (&gt;7 days), (n = 20) and/or mechanical ventilatory support (&gt;24 h), (n = 10) and/or mechanical cardiovascular support (IABP/VA ECMO placement), (n = 7) and/or suffered mortality (n = 2) in postoperative period were categorized as “poor” outcome. Presence of type II diabetes mellitus, Chronic obstructive pulmonary disease (COPD), higher grade of ischemic MR, larger LV end diastolic volume, use of cardiopulmonary bypass and allogenic blood transfusion during surgery were the determinants of “poor” outcome. Conclusion: Surgical myocardial revascularization improved global LV systolic function irrespective of baseline LV EF. Immediate postoperative outcome was strongly determined by presence of diabetes, COPD, higher grade of ischemic MR and larger LV end diastolic volumes. Preoperative (Baseline) LV EF and myocardial performance index did not determine “poor” postoperative outcome following surgical myocardial revascularization in subjects with LVEF &gt;35%.

Early Right Heart Remodeling in Patients With Mitral Valve Prolapse.

Mitral valve prolapse (MVP) has been associated with left heart remodeling. This study explored cardiac remodeling in patients with MVP without significant regurgitation, focusing on the right heart. This single-center study enrolled consecutive patients referred to trans-thoracic-echocardiography (TTE) with MVP, excluding those with significant regurgitation or known cardiovascular or pulmonary diseases. A group of healthy controls was included. Forty-nine patients with MVP and 54 controls were finally selected (mean age of 62, 52-71; 52% males), and echocardiographic parameters were compared among groups. Twenty-nine (41%) patients with MVP showed tricuspid valve prolapse (TVP). Patients with MVP, irrespective of TVP, showed greater tricuspid annulus (systolic annulus: 31±6 vs. 32±5 vs. 27±3mm for MVP+/TVP-, MVP+/TVP+, and controls, respectively; all p < 0.01) and greater minimum right atrial volume indexed (13, 12-15mL/m2vs. 15, 12-20mL/m2 vs. 11, 10-14mL/m2; all p < 0.05). Right ventricular dimensions and systolic indexes did not differ among groups, except TAPSE, which was significantly greater in MVP+/TVP+ patients compared to controls (25±4vs. 22±3mm, p = 0.004). A significant correlation (ρ = 0.43; p < 0.001) and an independent association at multivariate analysis (ß = 0.28; 95% CI 0.09-0.47; p = 0.004) were observed between end-systolic tricuspid diameter and TAPSE. In patients with MVP with less-than-moderate mitral or tricuspid regurgitation, dilation of the right atrium and tricuspid annulus was found. The latter finding was associated with increased values of TAPSE, which should then be used with caution, while other indexes may be preferred when assessing the systolic function of these patients.

Weekly Journal Scan: RESHAPing potential treatment indications for functional mitral regurgitation in heart failure.

Weekly Journal Scan: RESHAPing potential treatment indications for functional mitral regurgitation in heart failure.

DELINEATE-Regurgitation: deep learning for automated assessment of aortic, mitral, and tricuspid regurgitation from echocardiography

Abstract Background Valvular heart diseases, including aortic regurgitation (AR), mitral regurgitation (MR), and tricuspid regurgitation (TR) are significant contributors to cardiovascular morbidity and mortality worldwide. Artificial intelligence (AI) may improve echocardiographic assessment, but no models to date have successfully evaluated valvular regurgitation. Purpose The goal of this study was to develop an AI system to improve the accuracy of echocardiographic AR, MR, and TR interpretation. Methods Complete transthoracic echocardiogram (TTE) studies performed at a single center were split into train (n=65,301), validation (14,018), and test sets (13,746). The Deep Learning for Echo Analysis, Tracking, and Evaluation of Valvular Regurgitation (DELINEATE-Regurgitation) system intakes entire TTE studies, identifies color Doppler clips showing each valve, and yields a study level classification of AR, MR, and TR on a 6-grade scale (none/trace, mild, mild-moderate, moderate, moderate-severe, severe) using the cardiologist interpretation as a reference standard. This system used a hybrid neural network, leveraging the spatiotemporal feature learning capabilities of convolutional neural networks with the sequential processing strengths of transformer networks. The end-to-end hybrid approach allows the model to learn nuanced representations of the data including features within and across color Doppler videos. Model accuracy was assessed using quadratically weighted Cohen’s kappa (k), area under the receiver operator characteristic curve (AUROC) for the detection of both "moderate or greater" and "severe" regurgitation, and AI-cardiologist agreement the 6-grade scale. Additionally, an analysis was conducted using a 4-grade regurgitation scale (none/trace, mild, moderate, and severe) by rolling up intermediate classes (mild-moderate and moderate-severe) into the next higher class for both cardiologist determinations and model predictions. Results The DELINEATE-Regurgitation system demonstrated a high accuracy in the classification of AR (k=0.857), MR (k=0.867), and TR (k=0.847) (Figure 1). DELINEATE predicted the same severity as cardiologists (AR 91.8%, MR 79.9%, TR 77.7%) or within ±1 grade accuracy (AR 99.5%, MR 98.6%, TR 98.6%). The models had excellent binary discrimination in the detection of moderate or greater (AR AUROC 99.4, MR 98.6, TR 98.1) and severe (AR 99.7, MR 99.3, TR 99.6) regurgitation (Figure 2). In the 4-grade scale, the model had exact agreement with cardiologists in 92.3% of AR, 82.4% of MR, and 80.6% of TR cases. Panel adjudication of AI-cardiologist disagreement and correlation with quantitative metrics at higher levels of regurgitation will be presented. Conclusions The DELINEATE-Regurgitation AI system demonstrates a high level of accuracy in the assessment of AR, MR, and TR using color Doppler TTE videos. Future work will focus on automating quantification and developing strategies for optimal clinical deployment.Figure 1 - Confusion MatricesFigure 2 - ROC Curves

Evidence that mitral and/or tricuspid regurgitation diminishes stroke volume increase during exercise

Abstract Background and Purpose The severity of heart failure can be evaluated by peak oxygen consumption (VO2). Cardiac output is one of the major essential factors to determine the VO2. Therefore, cardiac output increases linearly as the exercise intensity increases. However, in mitral regurgitation, effective stroke volume decreases due to some blood flowing back into the left atrium from the left ventricle. This reduction may compromise oxygen delivery to working muscles and diminish oxygen uptake. Peak VO2/HR is known to indicate the stroke volume at the peak exercise, but since c(A-V)O2 difference shows almost a similar change pattern during a ramp protocol, VO2/HR during the load is also reported to be an indicator of stroke volume (SV) at that work rate. However, there are no investigations that have examined the extent to which the increase in cardiac output during stress is affected by the severity of mitral regurgitation. Therefore, we investigated the influence of the degree of regurgitant volume in mitral regurgitation (MR) and tricuspid regurgitation (TR) affects the SV increasing response to exercise load. Additionally, we examined whether blunted SV increase influences on the peak VO2. Methods Among 525 patients who underwent cardiopulmonary exercise test (CPX) at our institution from January 2023 to October 2023, 518 patients (143 females, 375 males, mean age 65.2±15.0 years old) where precise analyses of CPX was possible. CPX was performed using breath-by-breath gas analysis, and an incremental load test (10watts/min) was administered until exhaustion. The rate of increase in VO2/HR per watt during an incremental loading (Δ(VO2/HR)/ΔWR) was used as an indicator of the degree of increase in SV. Typically, SV increases up to 60% of maximum load, around AT, after which it stops increasing and plateaus. Therefore, the slope of Δ(VO2/HR)/ΔWR was examined from the initiation of ramp loading to AT. The degree of reflux was evaluated by echocardiography and classified as none/trivial, mild and moderate/severe. The number of people in each group of None/trivial, mild, moderate/severe was, 392, 83, 30 for MR, and 416, 64, 24 for TR. Δ(VO2/HR)/ΔWR was evaluated for each degree of reflux, using ANOVA to determine whether there was a difference between groups. Results As shown in the Figure1, Δ(VO2/HR)/ΔWR decreased as the reflux flow rate increased for both MR and TR. Concurrently, peak VO2 also decreased in the moderate/severe group compared to the non/trivial-reflux group for both MR and TR (MR: 17.5±5.4 mL/min/kg vs. 14.9±3.5 mL/min/kg, TR: 17.2±5.3 mL/min/kg vs. 13.6±3.8 mL/min/kg). Conclusion The Δ(VO2/HR)/ΔWR obtained through CPX has been shown to be an index that can evaluate the severity of reflux. Additionally, it was also demonstrated that as regurgitation flow increased, true stroke volume decreases, which is correlated with a reduction in peak VO2.

Prevalence, mechanisms and prognostic impact of dynamic mitral regurgitation unmasked by handgrip exercise in patients with hypokinetic non-dilated and dilated cardiomyopathy

Abstract Background Recent studies suggest that mitral regurgitation (MR) is a dynamic condition influenced by global and regional left ventricular (LV) remodeling as well as mitral valvular deformation. Exercise testing plays a substantial role in assessing the hemodynamic relevance of MR and is recommended by current guidelines. Handgrip exercise may serve as alternative exercise intervention to bicycle exercise, as it is easy to perform even bedside. However, there are no data yet, on the prevalence, mechanisms and prognostic impact of dynamic MR in patients with dilated cardiomyopathy using isometric exercise testing. Aims We aimed to assess the prevalence, hemodynamic consequences, and prognostic impact of exercise-induced changes in MR in patients with hypokinetic non-dilated and dilated cardiomyopathy. Methods Patients with hypokinetic non-dilated and dilated cardiomyopathy and at least mild MR who underwent handgrip echocardiography at the University Hospital Duesseldorf between January 2018 and September 2021 were enrolled.Patients were followed-up for one year to assess clinical outcomes. We assessed all-cause mortality, HF-associated hospitalizations, MV surgery, transcatheter edge-to-edge repair (TEER), left ventricular assist device implantation and heart transplantation during follow-up. Results Fifty-eight patients were included (mean age 70±15 years; 41% female; mean LVEF 37±10%). At rest, 28 patients (48%) presented with mild MR, and 30 patients (52%) had moderate MR. Fifteen patients (26%) with non-severe MR at rest, developed dynamic severe MR during handgrip exercise. Patients with dynamic severe MR had advanced MR at rest, larger left atrial dimensions, and increased mitral annulus diameter (all p&amp;lt;0.01). During exercise, LVEDVi, LVESVi and parameters of local left ventricular remodeling (tenting height, tenting area) were increased in patients with dynamic severe MR compared to those with non-severe MR (all p&amp;lt;0.05). During one-year follow-up, there was no difference regarding all-cause mortality and HF hospitalizations in patients with dynamic severe MR and non-severe MR (Log-rank test Chi2 0.262; p=0.609)(Figure 1). However, patients with dynamic severe MR more often underwent mitral valve surgery/intervention than patients with non-severe MR (Log-rank test Chi2 29.41; p&amp;lt;0.001)(Figure 1). Conclusion Our results demonstrate that the evaluation of non-ischemic MR only at rest underestimates the full severity of the lesion. Handgrip exercise unmasks severe MR in every fourth patient with non-severe MR at rest. These data may have implications for therapeutic decision-making in symptomatic patients with hypokinetic non-dilated and dilated cardiomyopathy and non-severe MR at rest. TEER might present an effective treatment option to improve clinical outcomes in patients with non-ischemic cardiomyopathy and non-severe MR at rest but dynamic severe MR during exercise.Figure 1