Left Atrial Remodeling after Mitral Valve Repair for Primary Mitral Regurgitation: Evolution over Time and Prognostic Significance

Left atrial (LA) dilatation is associated with worse outcomes in primary mitral regurgitation (MR). However, the effects of mitral valve repair on LA size and its prognostic implications are not well known. In the current study, LA volume index (LAVi) and LA reservoir strain (LASr) were evaluated immediately before and after surgery, and during long-term follow-up in 226 patients undergoing mitral valve repair for primary MR (age 62 +/- 13 years, 66% male). Mean LAVi was reduced significantly after surgery and at long-term follow-up (from 56 +/- 28 to 38 +/- 21 to 32 +/- 17 mL/m(2); p = 42 mL/m(2) at long-term follow-up showed significant higher mortality rates compared to patients with LAVI < 42 mL/m(2) (p < 0.001), even after adjusting for clinical covariates. In conclusion, significant LA reverse remodeling was observed both immediately and at long-term follow-up after mitral valve repair. LA dilatation at long term follow-up after surgery was still associated with all-cause mortality

Extramitral Valvular Cardiac Involvement in Patients With Significant Secondary Mitral Regurgitation

Patients with secondary mitral regurgitation (SMR) often have extramitral valve cardiac involvement, which can influence the prognosis. SMR can be defined according to groups of extramitral valve cardiac involvement. The prognostic implications of such groups in patients with moderate and severe SMR (significant SMR) are unknown. A total of 325 patients with significant SMR were classified according to the extent of cardiac involvement on echocardiography: left ventricular involvement (group 1), left atrial involvement (group 2), tricuspid valve and pulmonary artery vasculature involvement (group 3), or right ventricular involvement (group 4). The primary end point was all-cause mortality. The prevalence of each cardiac involvement group was 17% in group 1, 12% in group 2, 23% in group 3%, and 48% in group 4. Group 3 and group 4 were independently associated with all-cause mortality (hazard ratio 1.794, 95% confidence interval 1.067 to 3.015, p = 0.027 and hazard ratio 1.857, 95% confidence interval 1.145 to 3.012, p = 0.012, respectively). In conclusion, progressive extramitral valve cardiac involvement (group 3 and group 4) was independently associated with all-cause mortality in patients with significant SMR.</p

Malignant Arrhythmic Mitral Valve Prolapse: A Continuum of Clinical Challenges from Diagnosis to Risk Stratification and Patient Management

Mitral valve prolapse (MVP) is a common valvular disease, which may remain a benign condition for a long period of time. However, some patients experience malignant ventricular arrhythmias and sudden cardiac death (SCD). It is still largely unknown how to risk-stratify these patients, and no specific recommendations have been proposed to help the clinical decision-making. We present the case of a young man whose first clinical presentation was an out-of-hospital cardiac arrest and was subsequently diagnosed with MVP. We highlighted the possible risk factors for SCD and the challenges in the clinical management of these patients

Left Atrial Remodeling after Mitral Valve Repair for Primary Mitral Regurgitation: Evolution over Time and Prognostic Significance

Left atrial (LA) dilatation is associated with worse outcomes in primary mitral regurgitation (MR). However, the effects of mitral valve repair on LA size and its prognostic implications are not well known. In the current study, LA volume index (LAVi) and LA reservoir strain (LASr) were evaluated immediately before and after surgery, and during long-term follow-up in 226 patients undergoing mitral valve repair for primary MR (age 62 &plusmn; 13 years, 66% male). Mean LAVi was reduced significantly after surgery and at long-term follow-up (from 56 &plusmn; 28 to 38 &plusmn; 21 to 32 &plusmn; 17 mL/m2; p &lt; 0.001). LASr reduced significantly after surgery but increased again during the long-term (from 23.6 &plusmn; 9.4 to 11.5 &plusmn; 5.0 to 17.3 &plusmn; 7.5%; p &lt; 0.001). Age, pre-operative LAVi, MR severity, and postoperative transmitral pressure gradient were associated with LA reverse remodeling by the long-term check-up. During a median follow-up of 72 (40&ndash;114) months, 43 (19%) patients died. Patients with LAVi &ge; 42 mL/m2 at long-term follow-up showed significant higher mortality rates compared to patients with LAVI &lt; 42 mL/m2 (p &lt; 0.001), even after adjusting for clinical covariates. In conclusion, significant LA reverse remodeling was observed both immediately and at long-term follow-up after mitral valve repair. LA dilatation at long term follow-up after surgery was still associated with all-cause mortality

Parameters associated with ventricular arrhythmias in mitral valve prolapse with significant regurgitation

Objective Mitral valve prolapse (MVP) has been associated with ventricular arrhythmias (VA), but little is known about VA in patients with significant primary mitral regurgitation (MR). Our aim was to describe the prevalence of symptomatic VA in patients with MVP (fibro-elastic deficiency or Barlow's disease) referred for mitral valve (MV) surgery because of moderate-to-severe MR, and to identify clinical, electrocardiographic, standard and advanced echocardiographic parameters associated with VA. Methods 610 consecutive patients (64±12 years, 36% female) were included. Symptomatic VA was defined as symptomatic and frequent premature ventricular contractions (PVC, Lown grade ≥2), non-sustained or sustained ventricular tachycardia (VT) or ventricular fibrillation (VF) without ischaemic aetiology. Results A total of 67 (11%) patients showed symptomatic VA, of which 3 (4%) had VF, 3 (4%) sustained VT, 27 (40%) non-sustained VT and 34 (51%) frequent PVCs. Patients with VA were significantly younger, more often female and showed T-wave inversions; furthermore, they showed significant MV morphofunctional abnormalities, such as mitral annular disjunction (39% vs 20%, p<0.001), and dilatation (annular diameter 37±5 mm vs 33±6 mm, p<0.001), lower global longitudinal strain (GLS 20.9±3.1% vs 22.0±3.6%, p=0.032) and prolonged mechanical dispersion (45±12 ms vs 38±14 ms, p=0.003) as compared with patients without VA. Female sex, increased MV annular diameter, lower GLS and prolonged mechanical dispersion were identified as independent associates of symptomatic VA. Conclusion In patients with MVP with moderate-to-severe MR, symptomatic VA are relatively frequent and associated with significant MV annular abnormalities, subtle left ventricular function impairment and heterogeneous contraction. Assessment of these parameters might help decision-making over further diagnostic analyses and improve risk-stratification

Long-Term Impact of Preventive Tricuspid Valve Annuloplasty on Right Ventricular Remodeling

In patients with primary mitral regurgitation (MR), concomitant tricuspid valve (TV) annuloplasty at the time of left-sided valve surgery is indicated in case of a dilated TV annulus ≥40 mm independent of the presence or severity of tricuspid regurgitation (TR). However, the long-term impact on right ventricular (RV) adverse remodeling is less well established and the benefit of preventive TV annuloplasty remains controversial. The aim of the study was to assess differences in long-term RV adverse remodeling and the development of significant TR in those patients. In total, 98 patients (mean age 65 ± 11 years, 85% men) with significant primary MR and TV annulus dilatation ≥40 mm without significant TR who underwent mitral valve (MV) repair with or without concomitant TV annuloplasty were included. Of the 98 patients, 28 patients underwent isolated MV repair without TV annuloplasty and 70 patients received concomitant TV annuloplasty at the time of MV surgery. The RV basal diameter (p = 0.03), RV long-axis diameter (p = 0.04), RV end-diastolic area (p </p

Prognostic Impact of Extra–Mitral Valve Cardiac Involvement in Patients With Primary Mitral Regurgitation

Background: In patients with severe primary mitral regurgitation (MR), the indication for surgery is currently based on the presence of symptoms, left ventricular dilatation and dysfunction, atrial fibrillation, and pulmonary hypertension. Objectives: The aim of this study was to evaluate the prognostic impact of the presence of extra–mitral valve cardiac involvement (including known risk factors but also severe left atrial [LA] dilatation and right ventricular [RV] dysfunction) in a large multicenter study of patients with primary MR. Methods: Patients with severe primary MR undergoing surgery were included and categorized according to the extent (highest) of cardiac involvement: group 0, no cardiac involvement; group 1, left ventricular involvement; group 2, LA involvement; group 3, pulmonary vasculature or tricuspid valve involvement; or group 4, RV involvement. The outcome was all-cause mortality. Results: A total of 1,106 patients were included (mean age 63 ± 12 years, 68% male). In total, 377 patients (34%) were classified in group 0, 239 (22%) in group 1, 213 (19%) in group 2, 180 (16%) in group 3, and 97 (9%) in group 4. Kaplan-Meier curve analysis revealed significantly worse survival (log-rank chi-square = 43.4; P < 0.001) with higher group. On multivariable analysis, age, male sex, chronic obstructive pulmonary disease, kidney function, and group of cardiac involvement were independently associated with all-cause mortality. For each increase in group, a 17% higher risk for all-cause mortality was observed (95% CI: 1.051-1.313; P = 0.005) during a median follow-up time of 88 months. Conclusions: In patients with severe primary MR, a novel classification system based on extra–mitral valve cardiac involvement may help refine risk stratification and timing of surgery, particularly including severe LA dilatation and RV dysfunction in the assessment

Evolution from mitral annular dysfunction to severe mitral regurgitation in Barlow's disease

OBJECTIVES: Barlow's disease (BD) is characterized by thick, redundant mitral valve (MV) leaflets, which can lead to prolapse and significant mitral regurgitation (MR). MV annular abnormalities are also commonly observed and increasingly recognized as possible primary pathology, with leaflet thickening being secondary to increased stress on the MV apparatus. To provide more insights into this hypothesis, the evolution of MV abnormalities over time in patients with BD was assessed. METHODS: A total of 64 patients (54 ± 12 years, 72% male) with BD who underwent MV surgery and had multiple transthoracic echocardiograms (TTE) before surgery were included. In total, 186 TTE were analysed (median time interval 4.2, interquartile range 2.2-6.5 years) including specific MV characteristics. RESULTS: At baseline, MV leaflet length, thickness, billowing height and annular diameter were larger in patients with BD compared to 59 healthy subjects. Systolic outward motion (curling) of the annulus was observed in 77% and severe mitral annular disjunction (≥5 mm) in 38% of patients with BD. Forty (63%) patients had MR grade I-II and 24 (37%) MR grade III-IV; at baseline, the 2 groups only differed in left atrial volume and in thickness and billowing height of the posterior leaflet, showing comparable MV annular abnormalities and dilatation despite different grades of MR. Over time, MV annulus diameter, leaflet length and billowing height increased significantly along with MR grade. CONCLUSIONS: In patients with BD, MV annulus abnormalities are present at an early stage and precede the development of significant MR, suggesting their substantial role in the pathophysiology of this disease and as an important target for surgical treatment

Familial occurrence of mitral regurgitation in patients with mitral valve prolapse undergoing mitral valve surgery

Background: Initial studies have suggested the familial clustering of mitral valve prolapse, but most of them were either community based among unselected individuals or applied non-specific diagnostic criteria. Therefore little is known about the familial distribution of mitral regurgitation in a referral-type population with a more severe mitral valve prolapse phenotype. The objective of this study was to evaluate the presence of familial mitral regurgitation in patients undergoing surgery for mitral valve prolapse, differentiating patients with Barlow's disease, Barlow forme fruste and fibro-elastic deficiency. Methods: A total of 385 patients (62 ± 12 years, 63% men) who underwent surgery for mitral valve prolapse were contacted to assess cardiac family history systematically. Only the documented presence of mitral regurgitation was considered to define ‘familial mitral regurgitation’. In the probands, the aetiology of mitral valve prolapse was defined by surgical observations. Results: A total of 107 (28%) probands were classified as having Barlow's disease, 85 (22%) as Barlow forme fruste and 193 (50%) patients as fibro-elastic deficiency. In total, 51 patients (13%) reported a clear family history for mitral regurgitation; these patients were significantly younger, more often diagnosed with Barlow's disease and also reported more sudden death in their family as compared with ‘sporadic mitral regurgitation’. In particular, ‘familial mitral regurgitation’ was reported in 28 patients with Barlow's disease (26%), 15 patients (8%) with fibro-elastic deficiency and eight (9%) with Barlow forme fruste (P < 0.001). Conclusions: In a large cohort of patients operated for mitral valve prolapse, the self-reported prevalence of familial mitral regurgitation was 26% in patients with Barlow's disease and still 8% in patients with fibro-elastic deficiency, highlighting the importance of familial anamnesis and echocardiographic screening in all mitral valve prolapse patients

Identification of known and unknown genes associated with mitral valve prolapse using an exome slice methodology

Purpose: Although a familial distribution has been documented, the genetic aetiology of mitral valve prolapse (MVP) is largely unknown, with only four genes identified so far: FLNA, DCHS1, DZIP1 and PLD1. The aim of this study was to evaluate the genetic yield in known causative genes and to identify possible novel genes associated with MVP using a heart gene panel based on exome sequencing. Methods: Patients with MVP were referred for genetic counselling when a positive family history for MVP was reported and/or Barlow's disease was diagnosed. In total, 101 probands were included to identify potentially pathogenic variants in a set of 522 genes associated with cardiac development and/or diseases. Results: 97 (96%) probands were classified as Barlow's disease and 4 (4%) as fibroelastic deficiency. Only one patient (1%) had a likely pathogenic variant in the known causative genes (DCHS1). However, an interesting finding was that 10 probands (11%) had a variant that was classified as likely pathogenic in six different, mostly cardiomyopathy genes: DSP (1×), HCN4 (1×), MYH6 (1×), TMEM67 (1×), TRPS1 (1×) and TTN (5×). Conclusion: Exome slice sequencing analysis performed in MVP probands reveals a low genetic yield in known causative genes but may expand the cardiac phenotype of other genes. This study suggests for the first time that also genes related to cardiomyopathy may be associated with MVP. This highlights the importance to screen these patients and their family for the presence of arrhythmias and of â - disproportionate' LV remodelling as compared with the severity of mitral regurgitation, unravelling a possible coexistent cardiomyopathy