Ventricular Functional Mitral Regurgitation Research Articles

Efficacy of Native T1 Mapping for Patients With Non-Ischemic Cardiomyopathy and Ventricular Functional Mitral Regurgitation Undergoing Transcatheter Edge-to-Edge Repair.

We investigated the efficacy of left ventricular (LV) myocardial damage by native T1mapping obtained with cardiac magnetic resonance (CMR) for patients undergoing transcatheter edge-to-edge repair (TEER).Methods and Results: We studied 40 symptomatic non-ischemic heart failure (HF) patients and ventricular functional mitral regurgitation (VFMR) undergoing TEER. LV myocardial damage was defined as the native T1Z-score, which was converted from native T1values obtained with CMR. The primary endpoint was defined as HF rehospitalization or cardiovascular death over 12 months after TEER. Multivariable Cox proportional hazards analysis showed that the native T1Z-score was the only independent parameter associated with cardiovascular events (hazard ratio 3.40; 95% confidential interval 1.51-7.67), and that patients with native T1Z-scores <2.41 experienced significantly fewer cardiovascular events than those with native T1Z-scores ≥2.41 (P=0.001). Moreover, the combination of a native T1Z-score <2.41 and more severe VFMR (effective regurgitant orifice area [EROA] ≥0.30 cm2) was associated with fewer cardiovascular events than a native T1Z-score ≥2.41 and less severe VFMR (EROA <0.30 cm2; P=0.002). Assessment of baseline LV myocardial damage based on native T1Z-scores obtained with CMR without gadolinium-based contrast media is a valuable additional parameter for better management of HF patients and VFMR following TEER.

Moderate functional mitral regurgitation: difference between atrial and ventricular mechanism of the regurgitation

Abstract Background/Introduction In severe functional mitral regurgitation (MR), further distinction of the mechanism of MR in atrial functional MR (aFMR) and ventricular functional MR (vFMR) has shown prognostic importance. However, no data are available on moderate functional MR, whose characteristics and prognosis are largely unknown. Purpose To assess clinical and echocardiographic characteristics of patients with moderate aFMR and vFMR and their potential difference in outcome. Methods Patients with moderate functional MR were retrospectively included. aFMR was defined as isolated mitral annulus dilatation in combination with preserved left ventricular ejection fraction (LVEF≥50%) without ischemic heart disease or LV dilatation. Patients were classified as vFMR when LVEF was reduced, LV was dilated and/or wall motion abnormalities were present. Mitral valve intervention and all-cause mortality were used as combined endpoint. Results In total 474 patients with moderate functional MR (mean age 67 ±12, 57% male) were evaluated, of which 136 (29%) had aFMR and 338 (71%) had vFMR as underlying mechanism. Among the clinical variables, patients with aFMR had more atrial fibrillation (77% vs. 35%; p&amp;lt;0.001), were less symptomatic (NYHA class ≥ III: 6% vs. 18%; p&amp;lt;0.001) and had better renal function (eGFR 73 ±23 ml/min/1,73m2 vs. 65 ±23 ml/min/1,73m2; p=0.005) as compared to vFMR. In the vFMR group, 49% of patients had ischemic heart disease. Among the echocardiographic variables, as expected in aFMR, LVEF was higher (42 ±14% vs. 55 ±13%; p&amp;lt;0.001), while LV volumes (LV end-diastolic volume index 55 ±13 mL/m2 vs. 82 ±38 mL/m2; p&amp;lt;0.001) and E/E’ ratio were smaller (10 ±4 vs. 15 ±4; p&amp;lt;0.001) as compared to vFMR. However left atrial (LA) volume index was similar between both groups (43 ±14 mL/m2 vs. 41 ±18 mL/m2; p=0.271). For the echocardiographic measures of the right heart, significant difference was observed only for TAPSE which was higher for the aFMR group (22 ±4mm vs. 20 ±5mm; p&amp;lt;0.001). During a median follow-up of 74 months [IQR: 46.8-107.0], 132 (30%) patients died and 30 (6%) underwent mitral valve intervention. Event-free survival analysis for the combined endpoint was significantly better for aFMR patients (Figure 1). Based on significant variables from the univariable Cox regression analysis, multivariable Cox regression analysis showed that the mechanism of functional MR (with aFMR being protective as compared to vFMR), age, male gender, impaired renal function, NYHA class, severe LA dilatation and TAPSE were independently associated with the combined endpoint (Table 1). Conclusion In patients with moderate functional MR, aFMR is independently associated with better event-free survival as compared to vFMR. Therefore, clear identification of the mechanism of MR implies a better risk stratification and may be helpful for the management of patients with moderate MR.

Impact of transcatheter edge-to-edge repair (TEER) of mitral valve on the clinical outcomes in the management of atrial functional mitral regurgitation

Abstract Background Atrial functional mitral regurgitation (aFMR) has become a novel topic of interest. Data on the safety and efficacy of transcatheter edge-to-edge repair (TEER) of mitral valve among patients with aFMR and ventricular functional mitral regurgitation (vFMR) is scarce and limited to single center studies. Purpose We conducted a systematic review and meta-analysis to assess the safety and efficacy of TEER in the management of aFMR vs vFMR and its impact on clinical outcomes. Methods PubMed/MEDLINE, Cochrane Library and EMBASE databases were queried to identify studies comparing the efficacy of TEER between aFMR and vFMR. The primary outcome of interest was mortality at 1 year and composite of all-cause mortality and heart failure (HF) hospitalizations. Secondary outcomes included mitral regurgitation (MR) reduction, presence of residual MR, improvement in NYHA functional class, postoperatively and at 1-year. Risk ratios (RR’s) and their corresponding 95% confidence intervals (CIs) were calculated using random-effects model. Results We included a total of 3,314 patients from 6 observational studies which met the inclusion criteria (mean age 63.8 ± 3.8 years, 43% male). There were 443 aFMR patients and 2871 vFMR patients with an average follow-up of 12 months. Mortality at 1-year and the composite outcome of all-cause mortality and heart failure hospitalizations were comparable between aFMR and vFMR groups (RR 1.06; 95% CI 0.64 - 1.75; p = 0.81 and RR 0.92; 95% CI 0.75 - 1.14; p = 0.47, respectively). There were no significant differences between aFMR and vFMR groups in terms of MR reduction postoperatively (RR 0.99; 95% CI 0.96 - 1.02; p = 0.53) or at 1-year (RR 1.15; 95% CI 0.96 - 1.38; p = 0.14). Moreover, the presence of residual MR grade ≥ 3+ postoperatively (RR 1.31; 95% CI 0.83 - 2.08; p = 0.25) and at 1-year (RR 0.96; 95% CI 0.44 - 2.11; p = 0.92) was similar between aFMR and vFMR cohorts. Overall, although there was a clinical improvement in symptoms in terms of NYHA functional class at 1 year (grade ≤ 2), there was no statistical significance between the two groups (RR 1.02; 95% CI 0.93 - 1.11; p = 0.74). Conclusion This meta-analysis suggests that transcatheter edge-to-edge repair is likely to be an efficacious and safe option in patients with aFMR and vFMR. Future randomized control trials are needed to fully assess the clinical impact of this procedure in the two MR etiologies.Figure 1Figure 2

How should right ventricle remodeling be assessed in women and men with chronic mitral regurgitation?

Abstract Funding Acknowledgements Type of funding sources: Public Institution(s). Main funding source(s): Haukeland University Hospital Introduction Right ventricular (RV) dysfunction has a negative impact in patients with mitral regurgitation (MR), yet its assessment by two-dimensional (2D) echocardiography remains challenging. It is unclear which echocardiographic parameter best reflects RV remodeling in chronic MR. Purpose To assess 2D and three-dimensional (3D) measures of RV size and function in relation to MR severity. Methods Patients in the 3D-PRIME (3D Echocardiography and Cardiovascular Prognosis in Mitral Regurgitation) study with moderate or severe MR by combined transthoracic/transesophageal assessment and no other severe valve disease were examined at our heart valve clinic between 2020–2022. RV remodeling was assessed in 2D by the basal diameter, tissue Doppler peak systolic velocity at the lateral tricuspid ring (RV s´), tricuspid annular plane systolic excursion (TAPSE), and RV free wall longitudinal strain (RV FWS); and in 3D by end-diastolic volume (3D RVEDV), end-systolic volume (3D RVESV), ejection fraction (3D RVEF) and fractional area change (3D RVFAC). Results 100 patients with moderate or severe MR (54 with degenerative MR; 26 with atrial functional MR; 20 with ventricular functional MR) were included. Women (n=38) had smaller MR regurgitation volumes and RV size, similar TAPSE and RV s´, but higher 3D RVEF, 3D RVFAC and RV strain normalized for 3D RVEDV (all p &amp;lt;0.05). More severe RV remodeling with larger volumes, and lower 3D RVFAC (all p &amp;lt;0.05), and 3D RVEF (p = 0.05) was detected in severe MR by 3D, but not by 2D RV measures (Figure). In ROC analyses, 3D RVESV was strongest associated with severe MR (area under curve 0.68, p &amp;lt;0.01, Figure). In linear regression analysis, increasing 3D RVESV was associated with higher body mass index, larger MR regurgitation volume, male sex, and larger 3D left atrial volumes (R2 0.48, p &amp;lt;0.001). Conclusion RV remodeling in severe MR is detected by 3D, but not by routine 2D echocardiography. The 3D RV end-systolic size best reflects MR severity.

Implications of the Mitral Leaflet Coaptation Pattern on Clinical Outcomes in Patients With Functional Mitral Regurgitation

The classification of secondary mitral regurgitation (MR) is based on atrial functional MR (AFMR) or ventricular functional MR (VFMR) and volume changes, but the mitral leaflet coaptation angle also contributes to the MR mechanism. The clinical implications of the coaptation angle on cardiovascular (CV) outcomes have not been well evaluated. A total of 469 consecutive patients (265 AFMR vs 204 VFMR) with more than moderate MR were evaluated for the occurrence of heart failure, mitral valve operations, and CV death. The coaptation angle was assessed by measuring the internal angle between both leaflets at mid-systole using the apical 3-chamber view. A coaptation angle ≥130° was classified as leaflet flattening, and an angle <130° was classified as leaflet tethering. AFMR and VFMR were associated with higher frequencies of leaflet flattening and tethering, respectively. AFMR was more likely to be associated with older age, atrial fibrillation, and preserved ejection fraction, all of which were related to leaflet flattening. During a follow-up of 2.3years, 83 patients had heart failure (17.7%), 21 patients underwent mitral valve operations (4.5%), and 34 patients died (7%). Compared with leaflet tethering, leaflet flattening was more significantly related to CV events, whereas CV event rates were less markedly different in A/VFMR. Irrespective of A/VFMR, leaflet flattening and atrial fibrillation were associated with a higher frequency of CV events. Adjusted analysis showed that leaflet flattening remained an independent predictor of CV events (hazard ratio 3.5, 95% confidence interval 1.11 to 4.88, p=0.003), whereas A/VFMR did not. In conclusion, the leaflet coaptation angle in patients with functional MR could provide risk stratification superior to that of A/VFMR. Leaflet flattening appears to be associated with unfavorable clinical outcomes.

Transcatheter edge-to-edge mitral valve repair with extended clip arms for ventricular functional mitral regurgitation

BackgroundThe new sizing options of the MitraClip system (Abbott Vascular, Abbott Park, IL, USA) with extended clip arms were recently developed. Its applicability and effectiveness for ventricular functional mitral regurgitation (VFMR) are yet to be investigated. MethodsWe retrospectively reviewed consecutive patients with symptomatic VFMR who underwent transcatheter edge-to-edge repair between 2018 and 2022 at the Sakakibara Heart Institute. Pre- and post-procedural mitral valve morphologies were assessed using three-dimensional transesophageal echocardiography. ResultsIn a total of 104 VFMR patients, the posterior mitral leaflet length was 12.8 ± 2.8 mm and 92 % was indicative of the extended arm (≥9 mm). Although baseline VFMR was more severe in the patients treated with the extended arms (n = 35, XT group) than the patients treated with the standard arms (n = 69, NT group), the decrease in VFMR was greater in the XT group (delta three-dimensional vena contracta area − 43 ± 33 mm2 vs. -31 ± 22 mm2, p = 0.030) and residual VFMR was similar between the groups, with a significantly greater reduction in the mitral annulus anterior-posterior diameter (−4.9 ± 2.2 mm vs −3.1 ± 2.1 mm, p < 0.001) and mitral annulus area in the XT group. The use of extended arms was independently associated with shorter procedure time (81 ± 26 min vs 108 ± 41 min) after adjustment for device generation and the number of clips (p = 0.017). ConclusionsMost VFMR patients had enough leaflet lengths for transcatheter edge-to-edge repair using the MitraClip with the extended arms, which was associated with shorter procedure time and a greater decrease in the mitral annular size.

914 ATRIAL AND VENTRICULAR FUNCTIONAL MITRAL REGURGITATION: CLINICAL CHARACTERISTICS AND OUTCOMES IN MITRACLIP TREATED PATIENTS

Abstract Background mitral regurgitation (MR) is the second most common valvular heart disease in Europe. In the contest of functional (or secondary) MR recently has emerged a new entity, the atrial functional MR. This form is due to left atrial dilatation, it has no significant degenerative change in mitral valve complex or significant LV systolic disfunction. Conversely the ventricular functional mitral regurgitation (V-FMR) is due to systolic disfunction and left ventricular dilatation. Aim the aim of this study was to evaluate the differences in clinical characteristics and outcomes of patients with AFMR and VFMR treated with Mitraclip. Methods a retrospective analysis collected consecutive patients with functional MR who underwent transcatheter mitral valve repair using Mitraclip system in our division. A total of 161 patients were divided into the following two categories: VFMR (127 patients), defined as EF&amp;lt;40% or EF ≥40% with history of myocardial infarction, and AFMR (34 patients) identified as EF≥50% and LAVi &amp;gt;48 mL/m2. Baseline and clinical characteristics, echocardiographic parameters and 12 months clinical outcomes (overall mortality at 12 months, MACE at 12 months, re-hospitalization for heart failure (HF), re-hospitalization from other causes at 12 months and number of re-hospitalization at 12 months) were analyzed. Results compared to AFMR, patients with VFMR were younger (73 vs 78 years) had a higher man prevalence (72,4% vs 50%), higher rate of: hypercholesterolemia (79,5% vs 67,6%), smokers (14,2% vs 5,9%), diabetes (39,4% vs 20,6%), chronic kidney disease (55,9% vs 47,1%), NT-proBNP mean value (4403,437 pg/ml vs 2063,409 pg/ml), NYHA class ≥III (84.3 vs 52.9%) and lower rate of hypertension (85% vs 97.1%). In AFMR population there was higher prevalence of atrial fibrillation (70.6% vs 45.7%) and tricuspid valve regurgitation ≥2+ (82.3% vs 68,5%). Moreover, in this group, was lower the all-cause mortality rate at 12 months (9.4 vs 22%), MACE at 12 months (4.5 vs 24.5%), re-hospitalization for HF (15.6% vs 33.1%), re-hospitalization from other causes at 12 months (18.8% vs 31.6%) and number of re-hospitalization at 12 months ≥1 (31,3% vs 59.9%). Conclusion our analysis demonstrated that clinical outcomes at 12 months were lower for the AFMR group. These data are consistent with the literature, where AFMR is considered to have a better prognosis than VFMR, and underline the importance of differentiating these two types of population.

Abstract 12425: The Interplay Between Left Atrial and Mitral Valvular Remodeling in Subtypes of Mitral Regurgitation

Background: The interaction between left atrial (LA) mechanics and mitral valve remodeling patterns in patients with mitral regurgitation (MR) is poorly described. Objectives: To assess three-dimensional (3D) LA volumes and strain in relation to 3D mitral valve morphology in patients with degenerative vs. functional MR. Methods: Patients included in the 3D-PRIME (3D Echocardiography and Cardiovascular Prognosis in Mitral Regurgitation) study at our heart valve clinic between 2020-2022 and with moderate or severe MR by combined transthoracic/transesophageal assessment were examined. LA remodeling was assessed by 3D maximum and minimum LA volume, reservoir strain (LASr) and contraction strain (LASct). Mitral valve annulus area, anterior and posterior leaflet length and area, tenting volumes and non-planar angle were measured using dedicated 3D mitral valve software. Results: 100 patients with moderate or severe MR were included. Patients with atrial functional MR (n=26) were older, more often women and had higher heart rate compared to degenerative MR (n=54) and ventricular functional MR (n=20) (p &lt;0.05). They also had larger LA volumes and severely impaired LASr and LASct despite smaller MR regurgitation volumes compared to MR by other mechanisms (Figure). Mitral annulus area was comparable between groups, but anterior mitral leaflet was higher, with larger area and the non-planar angle wider in functional MRs (p &lt;0.05). In multivariable analysis, low LASr (below median) was associated with larger LA volume, and higher anterior mitral leaflet height independent of age, sex, heart rate, left ventricular global longitudinal strain, and right ventricular stroke volume (Nagelkerke R 2 0.67, p &lt;0.01). In a similar model, low LASct was only associated with larger LA volumes. Conclusions: Patients with atrial functional MR have large LAs with severely impaired LA function and a specific mitral valve remodeling pattern at lower MR regurgitation volumes.

Transcatheter edge to edge repair using the ease-of-use valve clamp system for functional mitral regurgitation: a primary report.

The ValveClamp system is a novel edge-to-edge mitral valve repair system designed for the ease of operation. We report the outcomes of our initial experience of treating functional mitral regurgitation (MR) with the ValveClamp system. The subjects of this study were patients with symptomatic functional MR despite standard medical therapy, who were treated with transapical ValveClamp implantation. The patients were divided into an atrial functional mitral regurgitation (AFMR) group and a ventricular functional mitral regurgitation (VFMR) group. Clinical and echocardiographic outcomes were evaluated at baseline and then at the 3-month follow up. Twelve patients, with a median age of 71years (range 65-78years), were assigned to the AFMR group (n = 5) or the VFMR group (n = 7). The device implantation rate was 100%, and 10 (83.3%) patients required implantation of only one clamp. The catheter time was less than 10min in half of the patients, the fastest time being 5min. There were no procedure-related complications. At the 3-month follow up, all patients were free from all-cause mortality, surgery, and rehospitalization. MR improved to ≤ 2 + in all 12 patients with MR grade 3 + or 4 + at baseline, (100%) and to ≤ 1 + in 9 of these patients (75%), with a low-pressure gradient. The left atrial diameter and the left ventricular end diastolic diameter decreased significantly in both the AFMR and VFMR groups. The left ventricular eject fraction at the 3-month follow up showed a rising trend in both the AFMR and VFMR groups, whereas PASP decreased remarkably. All 12 patients with baseline NYHA functional class III/IV (100%) showed improvement of at least 1 class, and 2 of these patients (16.7%) showed improvement of at least 2 classes. The ValveClamp system is simple and effective for transapical transcatheter edge to edge repair in patients with functional MR.

Outcomes After Transcatheter Edge-to-Edge Mitral Valve Repair According to Mitral Regurgitation Etiology and Cardiac Remodeling

BackgroundTranscatheter edge-to-edge repair (TEER) has been increasingly used for selected patients with mitral regurgitation (MR), but limited data are available regarding clinical outcomes in patients with varied etiology and mechanism of MR. ObjectivesThe aim of this study was to evaluate the outcomes of TEER according to etiology and left ventricular (LV) and left atrial remodeling. MethodsConsecutive patients who underwent TEER between 2007 and 2020 were included in the analysis. Among patients with functional MR (FMR), those with predominant LV remodeling were classified as having ventricular FMR (v-FMR), whereas those without LV remodeling but predominant left atrial remodeling were classified as having atrial FMR (a-FMR). The primary outcome was a composite of all-cause mortality and heart failure hospitalization at 2 years and was compared among patients with degenerative MR (DMR), a-FMR, and v-FMR. ResultsA total of 1,044 patients (11% with a-FMR, 48% with v-FMR, and 41% with DMR) with a mean Society of Thoracic Surgeons score of 8.6 ± 7.8 underwent TEER. Patients with a-FMR had higher rates of atrial fibrillation and severe tricuspid regurgitation with larger left and right atria, whereas patients with v-FMR had lower LV ejection fractions with larger LV dimensions. Residual MR more than moderate at discharge was not significantly different among the 3 groups (5.2% vs 3.2% vs 2.6%; P = 0.37). Compared with patients with DMR, 2-year event rates of the primary outcome were significantly higher in patients with a-FMR and v-FMR (21.6% vs 31.5% vs 42.3%; log-rank P < 0.001). ConclusionsDespite excellent procedural outcomes, patients with a-FMR and v-FMR had worse clinical outcomes compared with those with DMR.

Transcatheter Mitral Valve Repair in Patients With Atrial Functional Mitral Regurgitation

BackgroundAmong patients with severe functional mitral regurgitation (FMR), atrial functional mitral regurgitation (aFMR) represents an underrecognized entity. Data regarding outcomes after mitral valve transcatheter edge-to-edge repair (M-TEER) in aFMR remain scarce. ObjectivesThe objective of this study was to analyze the outcome of aFMR patients undergoing M-TEER. MethodsUsing patients from the international EuroSMR (European Registry of Transcatheter Repair for Secondary Mitral Regurgitation) registry undergoing M-TEER for FMR, the authors analyzed baseline characteristics and 2-year outcomes in aFMR in comparison to non-aFMR and ventricular FMR. Additionally, the impact of right ventricular dysfunction (RVD) (defined as right ventricular to pulmonary artery uncoupling) on outcome after M-TEER was assessed. ResultsAmong 1,608 FMR patients treated by M-TEER, 126 (7.8%) were categorized as aFMR. All 126 aFMR patients had preserved left ventricular function without regional wall motion abnormalities, left arterial dilatation and Carpentier leaflet motion type I. Procedural success (defined as mitral regurgitation ≤2+ at discharge) was 87.2% (P < 0.001) and New York Heart Association (NYHA) functional class significantly improved during follow-up (NYHA functional class III/IV: 86.5% at baseline to 36.6% at follow-up; P < 0.001). The estimated 2-year survival rate in aFMR patients was 70.4%. Two-year survival did not differ significantly between aFMR, non-aFMR, and ventricular FMR. Besides NYHA functional class IV, RVD was identified as a strong independent predictor for 2-year survival (HR: 2.82 [95% CI: 1.24-6.45]; P = 0.014). ConclusionsaFMR is a frequent cause of FMR and can be effectively treated with M-TEER to improve symptoms at follow-up. Advanced heart failure symptoms and RVD were identified as important risk factors for survival in aFMR patients.

Sex-Related Disparities In Atrial Functional Mitral Regurgitation.

Background Atrial functional mitral regurgitation (AFMR) is an increasingly recognized entity associated with left atrial dilation secondary to heart failure with preserved ejection fraction (HFpEF) and/or atrial fibrillation. Little is known about AFMR in females. Methods A retrospective chart review, of all patients over the age of 18 years who underwent a transthoracic echocardiogram (TTE) between Oct 1st 2019 and April 30th 2020 and were found to have moderate-to-severe and severe mitral regurgitation (MR), was performed. Key exclusion criteria included presence of: mitral valve repair or replacement, rheumatic mitral valve disease, mitral valve pathology such as perforation, cleft or endocarditis, congenital heart disease, left ventricular assist device or heart transplant, poor quality echocardiogram. Categorical variables (proportions) were compared using chi-squared test. Results Four hundred and twenty patients were found to have moderate-to-severe/severe mitral regurgitation. Of them, 51 were excluded based on the aforementioned criteria. Three hundred and sixty nine patients met inclusion criteria, including 192 (52%) females. Of them, 56 (15%) patients had primary or degenerative MR (DMR); 250 (68%) patients had left ventricular ejection fraction (LVEF) ≤ 50% and were classified as ventricular functional MR (VFMR); 45 (12%) patients had LVEF ≥ 50% with severe left atrial enlargement (left atrial biplane volume index > 40 ml/m2) and were classified as having AFMR; 3 (0.8%) patients had MR secondary to leaflet tethering; and in 15 (4%) patients the mechanism of MR was unclear. Remarkably, 80% (36) of patients with AFMR were females as compared to 54 % (30) patients with DMR and 46% (115) patients with VFMR (p< 0.001). Of the 162 female patients with FMR, 36 (22%) had AFMR. Notably, 27(60%) patients with AFMR carried a diagnosis of atrial fibrillation, 22 (49%) had been diagnosed with HFpEF, and 36 (80%) had hypertension. Conclusion There is a considerable burden of AFMR in females. Females are more likely to develop HFpEF and atrial fibrillation in women is also more likely to result in HFpEF, thereby portending increased risk of AFMR. Further research is needed to examine sex-related disparities in AFMR. Atrial functional mitral regurgitation (AFMR) is an increasingly recognized entity associated with left atrial dilation secondary to heart failure with preserved ejection fraction (HFpEF) and/or atrial fibrillation. Little is known about AFMR in females. A retrospective chart review, of all patients over the age of 18 years who underwent a transthoracic echocardiogram (TTE) between Oct 1st 2019 and April 30th 2020 and were found to have moderate-to-severe and severe mitral regurgitation (MR), was performed. Key exclusion criteria included presence of: mitral valve repair or replacement, rheumatic mitral valve disease, mitral valve pathology such as perforation, cleft or endocarditis, congenital heart disease, left ventricular assist device or heart transplant, poor quality echocardiogram. Categorical variables (proportions) were compared using chi-squared test. Four hundred and twenty patients were found to have moderate-to-severe/severe mitral regurgitation. Of them, 51 were excluded based on the aforementioned criteria. Three hundred and sixty nine patients met inclusion criteria, including 192 (52%) females. Of them, 56 (15%) patients had primary or degenerative MR (DMR); 250 (68%) patients had left ventricular ejection fraction (LVEF) ≤ 50% and were classified as ventricular functional MR (VFMR); 45 (12%) patients had LVEF ≥ 50% with severe left atrial enlargement (left atrial biplane volume index > 40 ml/m2) and were classified as having AFMR; 3 (0.8%) patients had MR secondary to leaflet tethering; and in 15 (4%) patients the mechanism of MR was unclear. Remarkably, 80% (36) of patients with AFMR were females as compared to 54 % (30) patients with DMR and 46% (115) patients with VFMR (p< 0.001). Of the 162 female patients with FMR, 36 (22%) had AFMR. Notably, 27(60%) patients with AFMR carried a diagnosis of atrial fibrillation, 22 (49%) had been diagnosed with HFpEF, and 36 (80%) had hypertension. There is a considerable burden of AFMR in females. Females are more likely to develop HFpEF and atrial fibrillation in women is also more likely to result in HFpEF, thereby portending increased risk of AFMR. Further research is needed to examine sex-related disparities in AFMR.

Influence of catheter ablation for atrial fibrillation on atrial and ventricular functional mitral regurgitation.

AimsThe purpose of this study was to compare the impact of catheter ablation on cardiac structural reverse remodelling and atrial (AFMR) and ventricular (VFMR) functional mitral regurgitation (MR), and the long‐term prognosis of patients with AFMR and VFMR.Methods and resultsThe retrospective study included persistent AF patients who had AFMR (n = 136, left atrial (LA) volume index >30 mL/m2 and left ventricular (LV) ejection fraction ≥40%) or VFMR (n = 31, LV ejection fraction <40% or LV regional asynergy) and had undergone the initial AF ablation from April 2015 to December 2019. Baseline and 6 month follow‐up echocardiography were performed to assess MR, LA, and LV sizes. MR improvement after ablation was comparable in the AFMR (64%) and VFMR groups (52%, P = 0.20). Patients with AFMR improvement showed a greater decrease in left atrial volume after ablation than those without (amount of change: −11.4 ± 15.1 vs. −2.3 ± 21.1 mL/m2, P = 0.01). Patients with VFMR improvement showed a greater increase in LV ejection fraction than those without (amount of change: 28.5 ± 13.6% vs. 9.0 ± 14.8%, P = 0.001). The composite endpoint of all‐cause death and heart failure hospitalization during the 2 year follow‐up period was more frequently observed in the VFMR than in the AFMR group (22.6% vs. 3.7%, P < 0.0001). Patients with MR improvement after catheter ablation less frequently demonstrated the composite endpoint than those without (1.9% vs. 15.6%, P < 0.0001).ConclusionsAtrial functional mitral regurgitation and VFMR improvement after ablation were associated with atrial and ventricular reverse remodelling, respectively. It is possible that long‐term prognosis is better in patients with AFMR than with VFMR, and in those with MR improvement than in those without.

Geometric differences of the mitral valve apparatus in atrial and ventricular functional mitral regurgitation

BackgroundFunctional mitral regurgitation (FMR) occurs in patients with annular dilation (atrial, aFMR) or patients with left ventricular (LV) disease (ventricular, vFMR). Meticulous understanding of the mechanisms underpinning regurgitation is crucial to optimize therapeutic strategies. MethodsPatients with moderate-severe FMR were identified from a registry of patients referred for transcatheter mitral valve intervention. In addition, controls without cardiovascular disease were identified. Differences in the geometry of the LV and mitral valve apparatus (including leaflet and tenting geometry, papillary muscle displacement and movement, annular dimensions, and dynamism) between atrial and ventricular FMR, and control subjects, were assessed using multiphasic cardiac CT. ResultsOf 183 FMR patients, 18 patients (10%) were found to have aFMR. The remaining patients had either ischemic or non-ischemic ventricular FMR. In aFMR, both increasing LV end-systolic volume (rho 0.701, p ​< ​0.01) and left atrial volume (rho 0.909, p ​< ​0.01) were associated with larger annular area. By contrast, in vFMR larger annular area was most strongly associated with larger left atrial volume (rho 0.63, p ​< ​0.01). In controls, increased annular area was associated with larger LVEDV (rho 0.78, p ​< ​0.01) and LVESV (rho 0.824, p ​< ​0.01), but not left atrial size (rho 0.16, p ​= ​0.45).Ventricular FMR comprised apicolaterally displaced, akinetic posteromedial papillary muscles, resulting in pronounced leaflet tethering, leaflet elongation compared to controls, and only modest relative LA dilatation. Compared to vFMR, aFMR was characterised by marked relative annular dilation, smaller but discernible mitral valve tenting, shorter leaflet lengths when related to annular size, but normal papillary geometry. ConclusionFMR is characterised by multiple changes within the mitral valve complex. Atrial and ventricular FMR differ significantly in terms of the drivers of annular size, and geometry and function of the subvalvular apparatus. This highlights the need to consider these as separate disease entities.

Atrial functional mitral regurgitation: The concept has evolved, but inconsistencies still remain.

In our commentary we elucidated the fact that functional mitral regurgitation (FMR) is divided into two morphological subtypes: annular dilation with normal leaflet motion (Carpentier type I) and restricted systolic motion with left ventricular remodeling or dysfunction (Carpentier type IIIb). However, these phenotypes show some degree of overlap and there are currently no distinctive diagnostic cut-off values, therefore they may represent a continuum of the same disease. Moreover, correct left chambers quantification is critical for differentiating between atrial FMR and ventricular FMR. Three-dimensional echocardiography can quantify better leaflet areas, lengths, and closing angles, as well as the coaptation index, by eliminating geometric assumptions and integrating tethering of all leaflet surface and annular area enlargement. Also, It is expected that the use of artificial intelligence solutions and the deployment of automated onboard software that requires no or limited human input will stimulate wider clinical use of three-dimensional echocardiography in left chambers quantification.

Clinical and Hemodynamic Effects of Percutaneous Edge-to-Edge Mitral Valve Repair in Atrial Versus Ventricular Functional Mitral Regurgitation

The present study aims to assess the clinical and hemodynamic impact of percutaneous edge-to-edge mitral valve repair with MitraClip in patients with atrial functional mitral regurgitation (A-FMR) compared with ventricular functional mitral regurgitation (V-FMR). Mitral regurgitation (MR) grade, functional status (New York Heart Association class), and major adverse cardiac events (MACE; all-cause mortality or hospitalization for heart failure) were evaluated in 52 patients with A-FMR and in 307 patients with V-FMR. In 56 patients, hemodynamic assessment during exercise echocardiography was performed before and 6 months after intervention. MR reduction after MitraClip implantation was noninferior in A-FMR compared with V-FMR (MR grade ≤2 at 6 months in 94% vs 82%, respectively, p <0.001 for noninferiority) and was associated with improvement of functional status (New York Heart Association class ≤2 at 6 months in 90% vs 80%, respectively, p = 0.2). Hemodynamic assessment revealed that cardiac output at 6 months was higher in A-FMR at rest (5.1 ± 1.5 L/min vs 3.8 ± 1.5 L/min, p = 0.002) and during peak exercise (7.9 ± 2.4 L/min vs 6.1 ± 2.1 L/min, p = 0.02). In addition, the reduction in systolic pulmonary artery pressure at rest was more pronounced in A-FMR: Δ SPAP -13.1 ± 15.1 mm Hg versus -2.2 ± 13.3 mm Hg (p = 0.03). MACE rate at follow-up was significantly lower in A-FMR versus V-FMR, with an adjusted odds ratio of 0.46 (95% confidence interval 0.24 to 0.88), which was caused by a reduction in hospitalization for heart failure. In conclusion, percutaneous edge-to-edge mitral valve repair with MitraClip is at least as effective in A-FMR as in V-FMR in reducing MR. However, the hemodynamic improvement and reduction of MACE were significantly better in A-FMR.

Computed tomography to identify risk factors for left circumflex artery injury during mitral surgery.

Cases in which the left circumflex coronary artery (LCX) runs close to the mitral annulus are considered high risk for LCX injury during mitral surgery. We investigated the anatomical relationship between the LCX and the mitral annulus using 3-dimensional (3D) computed tomography (CT). We constructed 3D-CT images of the LCX and the mitral annulus before surgery in 122 patients with mitral regurgitation (MR). We classified coronary dominance by 3D-CT and MR aetiologies (degenerative, atrial functional MR, ventricular functional MR and Barlow's disease) using echocardiography. We detected the point on the mitral annulus closest to the LCX (X point) and measured the minimum distance from the LCX to the mitral annulus (mCAD). We judged whether atrioventricular disjunction existed using CT. We also investigated the factors affecting mCAD and examined how coronary dominance and MR aetiologies relate to the location of the X point. The median mCAD was 4.2 mm (range 0.9-11.4 mm). Considering coronary dominance and MR aetiologies, mCAD was shorter in patients with left coronary dominance and Barlow's disease. The X point mostly existed on the lateral side of the posterior annulus, but it sometimes existed on the medial side. Multiple regression revealed left dominance and mitral annular disjunction as significant factors affecting mCAD (P = 0.01). The anatomical relationship between the LCX and the mitral annulus can be recognized using superimposed 3D-CT images. This approach is useful to avoid LCX injury in mitral valve surgery since the X point varies between patients.

Clinical and haemodynamic effects of percutaneous edge-to-edge mitral valve repair in atrial versus ventricular functional mitral regurgitation

Abstract Background Atrial functional mitral regurgitation (A-FMR) is a novel entity characterized by a MR due to atrial remodeling but with preserved left ventricular (LV) systolic function. Purpose To assess the clinical and haemodynamic impact of percutaneous edge-to-edge mitral valve repair with MitraClip in patients with A-FMR as compared to ventricular (V)-FMR. Methods MR grade, functional status (NYHA class), and major adverse cardiac events (MACE= all-cause mortality or hospitalization for heart failure (HF)) were evaluated in 52 A-FMR patients (pts.) and in 307 V-FMR pts. who underwent MitraClip implantation in 7 Belgian centers. In a subgroup of 56 pts (10 A-FMR and 46 V-FMR) haemodynamic assessment during a symptom-limited exercise echocardiography was performed before and 6-month after intervention. Results MitraClip implantation resulted in similar MR reductions in A-FMR and V-FMR (MR grade ≤2 at 6-month in 94% versus 82%, respectively (p=0.08)) and was associated with improvement of functional status in both groups (NYHA class ≤2 at 6 months in 90% versus 80%, respectively (p=0.2)). Serial haemodynamic assessment revealed that the cardiac output at 6-month was significantly higher in A-FMR pts. both at rest (5.1±1.5 L/min versus 3.8±1.5 L/min, p=0.002) and during peak exercise (7.9±2.4 L/min versus 6.1±2.1 L/min, p=0.02). Also the reduction in systolic pulmonary artery pressure (sPAP) was more pronounced in A-FMR: Δ sPAP at rest – 13.1±15.1 mmHg versus – 2.2±13.3 mmHg (p=0.03). During a follow-up period of 1.3±1.2 years MACE rate was significantly lower in A-FMR versus V-FMR with an adjusted OR of 0.46 (95% CI 0.24–0.88, see figure), which was mainly driven by a reduction in HF hospitalization. Conclusion Percutaneous edge-to-edge mitral valve repair with MitraClip is at least as effective in A-FMR as in V-FMR in reducing MR. But, the haemodynamic and clinical impact is stronger in A-FMR pts. Funding Acknowledgement Type of funding sources: None. MACE in A-FMR versus V-FMR pts

Differences in mitral valve geometry between atrial and ventricular functional mitral regurgitation in patients with atrial fibrillation: a 3D transoesophageal echocardiography study.

This study investigated geometric differences in mitral valve apparatus between atrial functional mitral regurgitation (A-FMR) and functional mitral regurgitation (FMR) with left ventricular (LV) dysfunction in patients with atrial fibrillation (AF) using 3D transoesophageal echocardiography (TOE). In total, 135 moderate or greater FMR patients with persistent AF or atrial flutter underwent 3D TOE. Fifty-six patients had A-FMR, defined as preserved LV ejection fraction (LVEF) of ≥50% and normal LV wall motion. Seventy-nine patients had ventricular FMR (V-FMR), defined as LV dysfunction (LVEF of <50%) or LV wall motion abnormality. To evaluate mitral leaflet coaptation, the coapted area was calculated as follows: total leaflet area (TLA) in end-diastole - closed leaflet area in mid-systole. Although annular area (AA) did not significantly differ between the two groups, TLA was significantly smaller in A-FMR than in V-FMR (P = 0.005). TLA/AA, indicating the degree of the leaflet remodelling, was significantly smaller in A-FMR than in V-FMR (P < 0.001). A-FMR had significantly smaller posterior mitral leaflet tethering height and angle measured at three anteroposterior planes (lateral, central, and medial) than V-FMR (all P < 0.001). However, vena contracta width (VCW) measured on long-axis view on TOE and coapted area, which correlated with VCW (r = -0.464, P < 0.001), were similar between the two groups. Mitral leaflet remodelling may be less in A-FMR compared with V-FMR. However, leaflet tethering was smaller in A-FMR than in V-FMR, and this may result in a similar degree of mitral leaflet coaptation and mitral regurgitation severity.

Prevalence, distribution, and determinants of pulmonary venous systolic flow reversal in severe mitral regurgitation.

This study aimed to evaluate the prevalence and distribution of pulmonary venous systolic flow reversal (PVSFR) in patients with severe mitral regurgitation (MR), and to examine the relationship between PVSFR profile and cardiac parameters. A total of 125 patients with severe MR who had transoesophageal echocardiography (TOE) performed were reviewed. Of these, 121 (96.8%) patients showed all four pulmonary venous (PV) flows by TOE. They were categorized into three groups by the MR aetiology: degenerative MR (DMR) (n = 72), ventricular functional MR (V-FMR) (n = 20), and atrial functional MR (A-FMR) (n = 16). Eighteen (16.7%) patients had PVSFR in all four PVs. Twenty-nine (26.9%) had PVSFR in three PVs, 23 (21.3%) in two PVs, and 23 (21.3%) in one PV. PVSFR appeared at right PVs more frequently compared with left PVs. A high number of PVSFR was significantly correlated with higher pulmonary capillary wedge pressure (PCWP) and 3D vena contracta area (3D-VCA). With regard to MR aetiology, the number of PVSFRs was correlated with high 3D-VCA in patients with DMR and A-FMR, while it was correlated with high PCWP in patients with V-FMR. Laminar-type PVSFR appeared more frequently in FMR compared with DMR, and it had a relationship with higher PCWP and lower right ventricular fractional area change (RVFAC). All four PV were detected in 96.8%, and 16.8% patients had PVSFR in all four PVs. PCWP and 3D-VCA were correlated with the number of PVSFRs in severe MR patients. Laminar-type PVSFR was related to higher PCWP and lower RVFAC.