Recovery of left ventricular function after surgical correction of mitral regurgitation caused by leaflet prolapse

Predicting postoperative systolic dysfunction in mitral regurgitation: CT vs. echocardiography

Introduction

Volume overload from mitral regurgitation can result in left ventricular systolic dysfunction. To prevent this, it is essential to operate before irreversible dysfunction occurs, but the optimal timing of intervention remains unclear. Current echocardiographic guidelines are based on 2D linear measurement thresholds only. We compared volumetric CT-based and 2D echocardiographic indices of LV size and function as predictors of post-operative systolic dysfunction following mitral repair.

Methods

We retrospectively identified patients with primary mitral valve regurgitation who underwent repair between 2005 and 2021. Several indices of LV size and function measured on preoperative cardiac CT were compared with 2D echocardiography in predicting post-operative LV systolic dysfunction (LVEFecho <50%). Area under the curve (AUC) was the primary metric of predictive performance.

Results

A total of 243 patients were included (mean age 57 ± 12 years; 65 females). The most effective CT-based predictors of post-operative LV systolic dysfunction were ejection fraction [LVEFCT; AUC 0.84 (95% CI: 0.77-0.92)] and LV end systolic volume indexed to body surface area [LVESViCT; AUC 0.88 (0.82-0.95)]. The best echocardiographic predictors were LVEFecho [AUC 0.70 (0.58-0.82)] and LVESDecho [AUC 0.79 (0.70-0.89)]. LVEFCT was a significantly better predictor of post-operative LV systolic dysfunction than LVEFecho (p = 0.02) and LVESViCT was a significantly better predictor than LVESDecho (p = 0.03). Ejection fraction measured by CT demonstrated significantly greater reproducibility than echocardiography.

Discussion

CT-based volumetric measurements may be superior to established 2D echocardiographic parameters for predicting LV systolic dysfunction following mitral valve repair. Validation with prospective study is warranted.

Sex-Specific Prognosis of Left Ventricular Size and Function Following Repair of Degenerative Mitral Regurgitation

BACKGROUND

Prior studies have demonstrated worse long-term outcomes for women after surgery for severe mitral regurgitation (MR). The current Class I indications for surgery for severe degenerative MR use cutoffs of left ventricular end-systolic dimension (LVESD) and left ventricular ejection fraction (EF) that do not account for known sex-related differences.

OBJECTIVES

The primary objective of this study was to assess long-term mortality following mitral valve repair in women compared with men on the basis of preoperative left ventricular systolic dimensions and EF.

METHODS

Consecutive patients who underwent isolated mitral valve repair for degenerative MR at a single institution between 1994 and 2016 were screened. Adjusted HRs for all-cause mortality were compared according to baseline LVESD, LVESD indexed to body surface area (LVESDi), and EF for men and women.

RESULTS

Among 4,589 patients, 1,825 were women (40%), and after a median follow-up period of 7.2 years, 344 patients (7.5%) had died. The risk for mortality for women increased from the baseline hazard at an LVESD of 3.6 cm, whereas an inflection point for increased risk with LVESD was not evident in men. Regarding LVESDi, the risk for women increased at 1.8 cm/m2 compared with 2.1 cm/m2 in men. For EF, women and men had a similar inflection point (58%); however, mortality was higher for women as EF decreased.

CONCLUSIONS

After mitral valve repair, women have a higher risk for all-cause mortality at lower LVESD and LVESDi and higher EF. These results support consideration of sex-specific thresholds for LVESDi in surgical decision making for patients with severe MR.

Position Statement on the Use of Myocardial Strain in Cardiology Routines by the Brazilian Society of Cardiology's Department Of Cardiovascular Imaging - 2023

Central Illustration : Position Statement on the Use of Myocardial Strain in Cardiology Routines by the Brazilian Society of Cardiology's Department Of Cardiovascular Imaging - 2023 Proposal for including strain in the integrated diastolic function assessment algorithm, adapted from Nagueh et al.67 Am: mitral A-wave duration; Ap: reverse pulmonary A-wave duration; DD: diastolic dysfunction; LA: left atrium; LASr: LA strain reserve; LVGLS: left ventricular global longitudinal strain; TI: tricuspid insufficiency. Confirm concentric remodeling with LVGLS. In LVEF, mitral E wave deceleration time < 160 ms and pulmonary S-wave < D-wave are also parameters of increased filling pressure. This algorithm does not apply to patients with atrial fibrillation (AF), mitral annulus calcification, > mild mitral valve disease, left bundle branch block, paced rhythm, prosthetic valves, or severe primary pulmonary hypertension.

Lessons learned from 10 years of experience with minimally invasive cardiac surgery

Since its inception more than a quarter of a century ago, minimally invasive cardiac surgery has attracted the increasing interest of cardiac surgeons worldwide. The need to surgically treat patients with smaller and better-tolerated incisions coupled with high-quality clinical outcomes, particularly in structural heart disease, has become imperative to keep pace with the evolution of transcatheter valve implantation. We have learned numerous lessons from our longstanding experience in this field of surgical care, especially in terms of endoscopic access via mini-thoracotomy. To improve the safety and efficacy of this minimally invasive endoscopic access, this study summarizes and highlights the lessons we have learned, acting as a template for newly established cardiac surgeons in minimally invasive techniques.

Research Opportunities in the Treatment of Mitral Valve Prolapse: JACC Expert Panel

In light of the adverse prognosis related to severe mitral regurgitation, heart failure, or sudden cardiac death in a subset of patients with mitral valve prolapse (MVP), identifying those at higher risk is key. For the first time in decades, researchers have the means to rapidly advance discovery in the field of MVP thanks to state-of-the-art imaging techniques, novel omics methodologies, and the potential for large-scale collaborations using web-based platforms. The National Heart, Lung, and Blood Institute recently initiated a webinar-based workshop to identify contemporary research opportunities in the treatment of MVP. This report summarizes 3 specific areas in the treatment of MVP that were the focus of the workshop: 1) improving management of degenerative mitral regurgitation and associated left ventricular systolic dysfunction; 2) preventing sudden cardiac death in MVP; and 3) understanding the mechanisms and progression of MVP through genetic studies and small and large animal models, with the potential of developing medical therapies.

Prognostic value of right ventricular remodelling in patients undergoing concomitant aortic and mitral valve surgery

AIMS

Long-term risk stratification and surgical timing remain suboptimal in concomitant aortic and mitral (double) valve surgery. This study sought to examine the predictors, changes, and prognostic implications of right ventricular (RV) remodelling in patients undergoing double-valve surgery.

METHODS AND RESULTS

In 152 patients undergoing double-valve surgery, four RV remodelling patterns were characterized using transthoracic echocardiography: normal RV size and systolic function (Pattern 1); dilated RV (tricuspid annulus diameter >35 mm) with normal systolic function (Pattern 2); normal RV size with systolic dysfunction (percentage RV fractional area change <35%; Pattern 3); and dilated RV with systolic dysfunction (Pattern 4). The primary endpoint was the composite of heart failure hospitalization and all-cause mortality. Patterns 1, 2, 3, and 4 RV remodelling were present in 41, 20, 23, and 16% of patients, respectively. Patients with Stage 4 RV remodelling had worse renal function, higher EuroSCORE II, and impaired left ventricular ejection fraction. During a 3.7-year median follow up, 45 adverse events occurred. Patterns 3 and 4 RV remodelling were associated with significantly higher adverse event rates compared with Pattern 1 (37 and 75% vs. 11%, P < 0.01) and had incremental prognostic value when added to clinical parameters and EuroSCORE II (χ2 increased from 30 to 66, P < 0.01). At 1 year after surgery (n = 100), Patterns 3 and 4 RV remodelling had a higher risk of adverse events compared with Pattern 1.

CONCLUSION

Right ventricular remodelling was strongly related to adverse outcomes and deserves consideration as part of the risk and decision-making algorithms in double-valve surgery.

Late plasma exosome microRNA-21-5p depicts magnitude of reverse ventricular remodeling after early surgical repair of primary mitral valve regurgitation

Introduction

Primary mitral valve regurgitation (MR) results from degeneration of mitral valve apparatus. Mechanisms leading to incomplete postoperative left ventricular (LV) reverse remodeling (Rev-Rem) despite timely and successful surgical mitral valve repair (MVR) remain unknown. Plasma exosomes (pEXOs) are smallest nanovesicles exerting early postoperative cardioprotection. We hypothesized that late plasma exosomal microRNAs (miRs) contribute to Rev-Rem during the late postoperative period.

Methods

Primary MR patients (n = 19; age, 45-71 years) underwent cardiac magnetic resonance imaging and blood sampling before (T0) and 6 months after (T1) MVR. The postoperative LV Rev-Rem was assessed in terms of a decrease in LV end-diastolic volume and patients were stratified into high (HiR-REM) and low (LoR-REM) LV Rev-Rem subgroups. Isolated pEXOs were quantified by nanoparticle tracking analysis. Exosomal microRNA (miR)-1, -21-5p, -133a, and -208a levels were measured by RT-qPCR. Anti-hypertrophic effects of pEXOs were tested in HL-1 cardiomyocytes cultured with angiotensin II (AngII, 1 μM for 48 h).

Results

Surgery zeroed out volume regurgitation in all patients. Although preoperative pEXOs were similar in both groups, pEXO levels increased after MVR in HiR-REM patients (+0.75-fold, p = 0.016), who showed lower cardiac mass index (-11%, p = 0.032). Postoperative exosomal miR-21-5p values of HiR-REM patients were higher than other groups (p < 0.05). In vitro, T1-pEXOs isolated from LoR-REM patients boosted the AngII-induced cardiomyocyte hypertrophy, but not postoperative exosomes of HiR-REM. This adaptive effect was counteracted by miR-21-5p inhibition.

Summary/Conclusion

High levels of miR-21-5p-enriched pEXOs during the late postoperative period depict higher LV Rev-Rem after MVR. miR-21-5p-enriched pEXOs may be helpful to predict and to treat incomplete LV Rev-Rem after successful early surgical MVR.

Perioperative management of patients with prosthetic heart valves-A narrative review

Worldwide, about 13% of the 200,000 annual recipients of prosthetic heart valves (PHV) present for various surgical procedures. Also, more and more females are opting for pregnancies after having PHV. All patients with PHV present unique challenges for the anesthesiologists, surgeons and obstetricians (in case of deliveries). They have to deal with the perioperative management of anticoagulation and a host of other issues involved. We reviewed the English language medical literature relevant to the different aspects of perioperative management of patients with PHV, particularly the guidelines of reputed societies that appeared in the last 20 years. Regression of cardiac pathophysiology following valve replacement is variable both in extent and timeline. The extent to which reverse remodeling occurs depends on the perioperative status of the heart. We discussed the perioperative assessment of patients with PHV, including focused history and relevant investigations with the inferences drawn. We examined the need for prophylaxis against infective endocarditis and management of anticoagulation in such patients in the perioperative period and the guidelines of reputed societies. We also reviewed the conduct of anesthesia, including general and regional anesthesia (neuraxial and peripheral nerve/plexus blocks) in such patients. Finally, we discussed the management of delivery in this group of high-risk patients. From the discussion of different aspects of perioperative management of patients with PHV, we hope to guide in formulating the comprehensive plan of management of safe anesthesia in such patients.

Stage-based approach to predict left ventricular reverse remodeling after mitral repair

Background

Although predictors of reverse left ventricular (LV) remodeling postmitral valve repair are critical for guiding perioperative decision‐making, there remains a paucity of randomized, prospective data to support the criteria that potential predictor variables must meet.

Methods and Results

The CAMRA CardioLink‐2 randomized trial allocated 104 patients to either leaflet resection or preservation strategies for mitral repair. The correlation of indexed left ventricular end‐systolic volume (LVESVI), indexed left ventricular end‐diastolic volume (LVEDVI), and left ventricular ejection fraction (LVEF) were tested with univariate analysis and subsequently with multivariate analysis to determine independent predictors of reverse remodeling at discharge and at 12 months postoperatively. At discharge, both LVESVI and LVEDVI were independently associated with their preoperative values (p < .001 for both) and LVEF by preoperative LVESVI (p < .001). Mitral ring size was favorably associated with the change in LVESVI (p < .05) and LVEF (p < .01) from predischarge to 12 months, while the mean mitral valve gradient after repair was adversely associated with the change in LVESVI (p < .05) and LVEDVI (p < .05). No significant associations were found between reverse remodeling and coaptation height nor mitral repair technique.

Conclusions

Beyond confirming the lack of impact of mitral repair technique on reverse remodeling, this investigation suggests that recommending surgery before significant LV dilatation or dysfunction, as well as higher postoperative mitral valve hemodynamic performance, may enhance remodeling capacity following mitral repair.

Left Ventricular Remodeling in Non-syndromic Mitral Valve Prolapse: Volume Overload or Concomitant Cardiomyopathy?

Mitral valve prolapse (MVP) is a common valvular disorder that can be associated with mitral regurgitation (MR), heart failure, ventricular arrhythmias and sudden cardiac death. Given the prognostic impact of these conditions, it is important to evaluate not only mitral valve morphology and regurgitation, but also the presence of left ventricular (LV) function and remodeling. To date, several possible hypotheses have been proposed regarding the underlying mechanisms of LV remodeling in the context of non-syndromic MVP, but the exact pathophysiological explanation remains elusive. Overall, volume overload related to severe MR is considered the main cause of LV dilatation in MVP. However, significant LV remodeling has been observed in patients with MVP and no/mild MR, particularly in patients with bileaflet MVP or Barlow’s disease, generating several new hypotheses. Recently, the concept of “prolapse volume” was introduced, adding a significant volume load to the LV on top of the transvalvular MR volume. Another possible hypothesis is the existence of a concomitant cardiomyopathy, supported by the link between MVP and myocardial fibrosis. The origin of this cardiomyopathy could be either genetic, a second hit (e.g., on top of genetic predisposition) and/or frequent ventricular ectopic beats. This review provides an overview of the different mechanisms and remaining questions regarding LV remodeling in non-syndromic MVP. Since technical specifications of imaging modalities impact the evaluation of MR severity and LV remodeling, and therefore might influence clinical decision making in these patients, this review will also discuss assessment of MVP using different imaging modalities.

Robotic Mitral Valve Repair: A Decade of Experience with Echocardiographic Follow-up

BACKGROUND

Surgical approaches for mitral valve (MV) disease have evolved with the aim of developing minimally invasive techniques. While the safety of robotic procedures has been documented, there are limited data on long-term echocardiographic follow-up. This review demonstrates outcomes of 11 years of robotic MV repair at a single, tertiary institution.

METHODS

From 2008 to 2019, 843 patients underwent robotic MV repair at our institution. Repeated measures generalized least squares (GLS) modelling was used to assess the echocardiographic changes over time.

RESULTS

The median age was 58 years (IQR 50.8, 65.5) (591 males, 70.1%). Mechanism of MR was posterior leaflet prolapse in 479 (56.8%), bileaflet prolapse in 325 (38.6%), and anterior leaflet prolapse in 36 (4.3%). There were 3 early deaths (0.4%) and 24 early reoperations (2.8%). Echocardiographic follow up demonstrated left ventricular end systolic and diastolic dimensions, left atrial volume index and pulmonary pressure all continuously improvement up to 2 years postoperatively. Ejection fraction immediately declined postoperatively but then gradually improved to near normal over 2 years. Survival and freedom from reoperation at 10 years were 93% and 92.6%, respectively. When surveyed after dismissal, 93.4% reported their activity level at or above their peers and 93.3% reported no activity limitation from cardiac symptoms.

CONCLUSIONS

Robotic MV repair is safe and effective with excellent long-term results, including echocardiographic parameters that demonstrated early improvement in cardiac chamber size and maintenance of postoperative cardiac function. Exceedingly low mortality rates and freedom from reoperation are comparable to those of the standard open repair.

Mitral repair with leaflet preservation versus leaflet resection and ventricular reverse remodeling from a randomized trial

OBJECTIVES

In the Canadian Mitral Research Alliance (CAMRA) Trial CardioLink-2 leaflet resection versus preservation techniques for posterior leaflet prolapse was investigated and no difference was shown in their effect on mean mitral gradient at peak exercise at 12 months postoperatively. The purpose of this subanalysis was to evaluate the effect of the 2 strategies on left ventricular (LV) reverse remodeling after repair.

METHODS

A total of 104 patients were randomized to either a leaflet resection or leaflet preservation strategy. Echocardiograms, performed at baseline (preoperative), predischarge, and 12 months postoperatively, were analyzed in a blinded fashion at a core laboratory.

RESULTS

All patients underwent successful mitral repair. At discharge, 3 patients showed moderate mitral regurgitation, whereas the remainder showed mild or less regurgitation. Compared with the baseline echocardiogram, the indexed end diastolic volume was reduced at the discharge echocardiogram (P < .0001) and was further reduced at the 12-month echocardiogram (P = .01). In contrast, the indexed end systolic volume did not significantly change from baseline assessed at the predischarge echocardiogram (P = .32) but improved at 12 months postoperatively (P < .0001), resulting in a corresponding improvement in ejection fraction at 12 months (P < .0001). The type of mitral repair strategy had no significant effect on LV reverse remodeling trends.

CONCLUSIONS

The mitral repair strategies used did not influence postoperative LV reverse remodeling, which occurred in stages. Although LV end diastolic dimensions recovered before discharge, improvements in LV end systolic dimension were evident 12 months after repair.

Mitral valve repair in chronic severe mitral regurgitation: short-term results and analysis of mortality predictors

Introduction

Mitral valve repair is the accepted treatment for mitral regurgitation (MR) but lack of resources and socioeconomic concerns delay surgical referral and intervention in developing countries. We evaluated immediate and short-term results of mitral valve repair for non-ischemic MR at our centre and aimed to identify the predictors of in-hospital and follow-up mortality.

Materials and methods

The study was conducted at a tertiary-level hospital in South India. All patients >18 years with severe non-ischemic MR who underwent mitral valve repair over a period of 6 years were included. Perioperative data was collected from hospital records and follow-up data was obtained by prospective methods.

Results

There were 244 patients (170 males). Most of the patients were in the age group 31-60 years (76.6%). Aetiology of MR was degenerative (n = 159; 65.2%), rheumatic (n = 34; 13.9%), structural (n = 42; 17.2%), or miscellaneous (n = 9; 3.7%). All patients underwent ring annuloplasty with various valve repair techniques. One hundred patients (44.7%) underwent additional cardiac procedures. At discharge, MR was moderate in 4 patients; the rest had no or mild MR. The mean hospital stay of survivors was 7.1 days (SD 2.52, range 5-25 days). There were 9 in-hospital deaths (3.68%) and 10 deaths during follow-up (4.2%). The mean follow-up period was 1.39 years, complete for 87.6%. Pre-operative left ventricle ejection fraction (LVEF) <60% (p = 0.04) was found to be significantly associated with immediate mortality. Logistic regression analysis detected age (p = 0.019), female sex (p = 0.015), and left ventricular (LV) dysfunction at discharge (p = 0.025) to be significantly associated with follow-up mortality.

Conclusion

Pre-operative LV dysfunction was identified as a significant risk factor for in-hospital mortality. Female sex, age greater than 45 years, and LV dysfunction at discharge were found to be significantly associated with follow-up mortality. Hence, it is important to perform mitral valve repair in severe regurgitation patients before significant LV dysfunction sets in for a better outcome.

Postoperative changes in left ventricular systolic function after combined mitral and aortic valve replacement in patients with rheumatic heart disease

BACKGROUNDS

We sought to identify short- and long-term changes in postoperative left ventricular systolic function in patients with rheumatic heart disease (RHD) who underwent combined aortic and mitral valve replacement.

METHODS

We analyzed 146 patients according to their preoperative left ventricular ejection fraction (LVEF) (113 with preoperative LVEF ≥50% and 33 with preoperative LVEF <50%). A restricted cubic spline model was used to assess the effect of time on the postoperative changes in echocardiographic parameters.

RESULTS

There were no significant difference in preoperative and immediately postoperative LVEF before discharge in either group. During median follow-up of 3.2 years (interquartile range: 1.3-4.7 years) after surgery, postoperative LVEF increased slightly and then plateaued in patients with preoperative LVEF ≥50%, whereas it increased over 3-4 years after surgery and then gradually decreased in patients with preoperative LVEF <50% (p < .001).

CONCLUSION

Long-term postoperative LVEF showed a downward trend in RHD patients with reduced preoperative LVEF, whereas it reached a plateau in RHD patients with normal preoperative LVEF.

Changes in Left Ventricular Ejection Fraction after Mitral Valve Repair for Primary Mitral Regurgitation

This study sought to identify the short- and long-term changes in left ventricular ejection fraction (LVEF) after mitral valve repair (MVr) in patients with chronic primary mitral regurgitation according to preoperative LVEF (pre-LVEF) and preoperative left ventricular end-systolic diameter (pre-LVESD). This study evaluated 461 patients. Restricted cubic spline regression models were constructed to demonstrate the long-term changes in postoperative LVEF (post-LVEF). The patients were divided into four groups according to pre-LVEF (<50%, 50–60%, 60–70%, and ≥70%). The higher the pre-LVEF was, the greater was the decrease in LVEF immediately after MVr. In the same pre-LVEF range, immediate post-LVEF was lower in patients with pre-LVESD ≥ 40 mm than in those with pre-LVESD < 40 mm. The patterns of long-term changes in post-LVEF differed according to pre-LVEF (p for interaction < 0.001). The long-term post-LVEF reached a plateau of approximately 60% when the pre-LVEF was ≥50%, but it seemed to show a downward trend after reaching a peak at approximately 3–4 years after MVr when the pre-LVEF was ≥70%. The patterns of short- and long-term changes in post-LVEF differed according to pre-LVEF and pre-LVESD values in patients with chronic primary mitral regurgitation after MVr.

Safety and performance of a novel transventricular beating heart mitral valve repair system: 1-year outcomes

OBJECTIVES

The objective of this study was to evaluate the safety and performance of a novel, beating heart procedure that enables echocardiographic-guided beating heart implantation of expanded polytetrafluoroethylene (ePTFE) artificial cords on the posterior mitral leaflet of patients with degenerative mitral regurgitation.

METHODS

Two prospective multicentre studies enrolled 13 (first-in-human) and 52 subjects, respectively. Patients were treated with the HARPOON beating heart mitral valve repair system. The primary (30-day) end point was successful implantation of cord(s) with mitral regurgitation reduction to ≤moderate. An independent core laboratory analysed echocardiograms.

RESULTS

Of 65 patients enrolled, 62 (95%) achieved technical success, 2 patients required conversion to open surgery and 1 procedure was terminated. The primary end point was met in 59/65 (91%) patients. Among the 62 treated patients, the mean procedural time was 2.1 ± 0.5 h. Through discharge, there were no deaths, strokes or renal failure events. At 1 year, 2 of the 62 patients died (3%) and 8 (13%) others required reoperations. At 1 year, 98% of the patients with HARPOON cords were in New York Heart Association class I or II, and mitral regurgitation was none/trace in 52% (n = 27), mild in 23% (n = 12), moderate in 23% (n = 12) and severe in 2% (n = 1). Favourable cardiac remodelling outcomes at 1 year included decreased end-diastolic left ventricular volume (153 ± 41 to 119 ± 28 ml) and diameter (53 ± 5 to 47 ± 6 mm), and the mean transmitral gradient was 1.4 ± 0.7 mmHg.

CONCLUSIONS

This initial clinical experience with the HARPOON beating heart mitral valve repair system demonstrates encouraging early safety and performance.

CLINICAL REGISTRATION NUMBERS

NCT02432196 and NCT02768870.

Predictive Value of Pre-Operative 2D and 3D Transthoracic Echocardiography in Patients Undergoing Mitral Valve Repair: Long Term Follow Up of Mitral Valve Regurgitation Recurrence and Heart Chamber Remodeling

The “ideal” management of asymptomatic severe mitral regurgitation (MR) in valve prolapse (MVP) is still debated. The aims of this study were to identify pre-operatory parameters predictive of residual MR and of early and long-term favorable remodeling after MVP repair. We included 295 patients who underwent MV repair for MVP with pre-operatory two- and three-dimensional transthoracic echocardiography (2DTTE and 3DTTE) and 6-months (6M) and 3-years (3Y) follow-up 2DTTE. MVP was classified by 3DTTE as simple or complex and surgical procedures as simple or complex. Pre-operative echo parameters were compared to post-operative values at 6M and 3Y. Patients were divided into Group 1 (6M-MR < 2) and Group 2 (6M-MR ≥ 2), and predictors of MR ≥ 2 were investigated. MVP was simple in 178/295 pts, and 94% underwent simple procedures, while in only 42/117 (36%) of complex MVP a simple procedure was performed. A significant relation among prolapse anatomy, surgical procedures and residual MR was found. Post-operative MR ≥ 2 was present in 9.8%: complex MVP undergoing complex procedures had twice the percentage of MR ≥ 2 vs. simple MVP and simple procedures. MVP complexity resulted independent predictor of 6M-MR ≥ 2. Favorable cardiac remodeling, initially found in all cases, was maintained only in MR < 2 at 3Y. Pre-operative 3DTTE MVP morphology identifies pts undergoing simple or complex procedures predicting MR recurrence and favorable cardiac remodeling.

Preoperative left atrial volume index is associated with postoperative outcomes in mitral valve repair for chronic mitral regurgitation

OBJECTIVE

To assess determinants of left atrial reverse remodeling after mitral valve repair and to evaluate the impact of preoperative left atrial volume on postoperative outcomes.

METHODS

We reviewed the records of 720 patients who underwent mitral valve repair from September 2008 to July 2015 and had preoperative measurement of left atrial volume index. We analyzed the association of preoperative left atrial volume index on early and late outcomes, and determined which baseline characteristics are associated with left atrial reverse remodeling, as measured by changes in left atrial volume index in 512 patients who had at least 1 postoperative measurement.

RESULTS

The median (interquartile range) preoperative left atrial volume index was 54.0 (44.0-66.0) mL/m². Preoperative left atrial volume index, age, body mass index, and atrial fibrillation were independently associated with the degree of left atrial reverse remodeling over the follow-up period. Reverse remodeling was greatest in patients with higher baseline left atrial volume index (P < .001), but less reverse remodeling was observed in patients with advanced age (P < .001), preoperative atrial fibrillation (P < .001), and extreme values of body mass index (P = .004), although these effects were moderately attenuated when limiting the analysis to 6-month follow-up. Secondary analysis demonstrated marginally significant effects of preoperative left atrial volume index on risks of early postoperative atrial fibrillation (P = .030) and late mortality (P = .077) after adjusting for age and sex.

CONCLUSIONS

In patients with degenerative mitral valve regurgitation who had mitral valve repair, preoperative left atrial volume index was associated with extent of left atrial reverse remodeling, risk of early postoperative atrial fibrillation, and late mortality. The majority of reverse remodeling occurs within the first month after operation and is greatest in younger patients.

Left ventricular remodeling after mini-mitral repair-does the complexity of mitral disease matter?

OBJECTIVES

Degenerative mitral valve (MV) regurgitation (MR) is associated with left ventricular (LV) dilatation. Surgical treatment of MR has been shown to favorably affect LV remodeling. We prospectively compared the long-term echocardiographic outcomes of LV remodeling following mini-mitral repair for simple versus complex MV disease.

METHODS

We prospectively followed up 203 consecutive patients who underwent mini-MV repair for severe degenerative MR over a 9-year period. Simple disease (n = 122 patients: posterior leaflet prolapse) was compared to complex disease (n = 81 patients: anterior, bilateral or commissural prolapse). Baseline demographics were similar between simple and complex groups (age: 63 ± 13 years vs 60 ± 15 years; p = .2; sex: 71% male vs 72% male, p = 1; preoperative MR grade ≥ 3+: 100%; n = 122; vs 100%; n = 81; p = 1), respectively.

RESULTS

Preoperative left ventricular ejection fraction (LVEF) was significantly lower in the complex group as compared to the simple group (57.2% simple vs 56.0% complex; p = .04). Preoperative LV end-systolic diameter (LVESD: 35 mm simple vs 36 mm complex, p < .05) and LV end-diastolic diameter (LVEDD: 50 mm simple vs 51 mm complex; p < .05), as well as LV mass index (99.5 g/m² vs 102.4 g/m² ; p = .06) were larger in the complex group. Despite different baseline characteristics of LV function and geometry, both groups had similar remodeling of LV after MV repair.

CONCLUSIONS

Patients with complex MV disease are referred late for surgical repair, causing LV function and dimensions to never fully recover. This suggests that earlier referral (before LV changes and potentially before symptoms) may be the preferred approach in those with complex disease.

Interrelationship Between Kidney Function and Percutaneous Mitral Valve Interventions: A Comprehensive Review

Percutaneous mitral valve repair is emerging as a reasonable alternative especially in those with an unfavorable surgical risk profile in the repair of mitral regurgitation. At this time, our understanding of the effects of underlying renal dysfunction on outcomes with percutaneous mitral valve repair and the effects of this procedure itself on renal function is evolving, as more data emerges in this field. The current evidence suggests that the correction of mitral regurgitation via percutaneous mitral valve repair is associated with some degree of improvement in cardiac function, hemodynamics and renal function. The improvement in renal function was more significant for those with greater renal dysfunction at baseline. The presence of Chronic Kidney Disease (CKD) in turn has been associated with poor long-term outcomes including increased mortality and hospitalization among patients who undergo percutaneous mitral valve repair. This was true regardless of the degree of improvement in GFR post repair advanced CKD. The adverse impact of CKD on long-term outcomes was consistent across all studies and was more prominent in those with GFR<30 mL/min/1.73 m². It is clear that from these contrasting evidences of improved renal function post mitral valve repair but poor long-term outcomes including increased mortality in patients with CKD, that proper patient selection for percutaneous mitral valve repair is key. There is a need to have better-standardized criteria for patients who should qualify to have percutaneous mitral valve replacement with Mitraclip. In this new era of percutaneous mitral valve repair, much work needs to be done to optimize long-term patient outcomes.

Possible mechanism of late systolic mitral valve prolapse: systolic superior shift of leaflets secondary to annular dilatation that causes papillary muscle traction

Progressive superior shift of the mitral valve (MV) during systole is associated with abnormal papillary muscle (PM) superior shift in late systolic MV prolapse (MVP). The causal relation of these superior shifts remains unclarified. We hypothesized that the MV superior shift is related to augmented MV superiorly pushing force by systolic left ventricular pressure due to MV annular dilatation, which can be corrected by surgical MV plasty, leading to postoperative disappearance of these superior shifts. In 35 controls, 28 patients with holosystolic MVP, and 28 patients with late systolic MVP, the MV coaptation depth from the MV annulus was measured at early and late systole by two-dimensional echocardiography. The PM tip superior shift was monitored by echocardiographic speckle tracking. MV superiorly pushing force was obtained as MV annular area × (systolic blood pressure - 10). Measurements were repeated after MV plasty in 14 patients with late systolic MVP. Compared with controls and patients with holosystolic MVP, MV and PM superior shifts and MV superiorly pushing force were greater in patients with late systolic MVP [1.3 (0.5) vs. 0.9 (0.6) vs. 3.9 (1.0) mm/m², 1.3 (0.5) vs. 1.2 (1.0) vs. 3.3 (1.3) mm/m², and 487 (90) vs. 606 (167) vs. 742 (177) mmHg·cm²·m^-2, respectively, means (SD), P < 0.001]. MV superior shift was correlated with PM superior shift ( P < 0.001), which was further related to augmented MV superiorly pushing force ( P < 0.001). MV and PM superior shift disappeared after surgical MV plasty for late systolic MVP. These data suggest that MV annulus dilatation augmenting MV superiorly pushing force may promote secondary superior shift of the MV (equal to late systolic MVP) that causes subvalvular PM traction in patients with late systolic MVP. NEW & NOTEWORTHY Late systolic mitral valve prolapse (MVP) is associated with mitral valve (MV) and papillary muscle (PM) abnormal superior shifts during systole, but the causal relation remains unclarified. MV and PM superior shifts were correlated with augmented MV superiorly pushing force by annular dilatation and disappeared after surgical MV plasty with annulus size and MV superiorly pushing force reduction. This suggests that MV annulus dilatation may promote secondary superior shifts of the MV (late systolic MVP) that cause subvalvular PM traction.

Mitral regurgitation: anatomy is destiny

Mitral regurgitation (MR) occurs when any of the valve and ventricular mitral apparatus components are disturbed. As MR progresses, left ventricular remodelling occurs, ultimately causing heart failure when the enlarging left ventricle (LV) loses its conical shape and becomes globular. Heart failure and lethal ventricular arrhythmias may develop if the left ventricular end-systolic volume index exceeds 55 ml/m2. These adverse changes persist despite satisfactory correction of the annular component of MR. Our goal was to describe this process and summarize evolving interventions that reduce the volume of the left ventricle and rebuild its elliptical shape. This 'valve/ventricle' approach addresses the spherical ventricular culprit and offsets the limits of treating MR by correcting only its annular component.

Valve repair to avoid prosthetic valve pathology: Mid-term results in mitral valve repair

Background

In this study, we aimed to present our results of mitral valve repair.

Methods

Between January 2007 and November 2016, a total of 128 patients (72 males, 56 females; mean age 51.8±17.2 years; range 16 to 84 years) who underwent mitral valve repair in our heart center were retrospectively analyzed. There were mitral regurgitation in 86.7% (n=111), mitral stenosis in 7.8% (n=10), and mixed type valve disease in 5.5% of the patients (n=7). Mitral ring annuloplasty was performed in 80.5% (n=103), implantation of the artificial chordae in 36.7% (n=47), open mitral commissurotomy in 13.3% (n=17), and Alfieri procedure in 6.3% (n=8) of the patients. Sixty-two patients (48.8%) underwent isolated mitral valve repair, while concomitant surgical procedures were performed in the remaining patients. Postoperative mean follow-up was 52 months.

Results

Early (30-day) mortality was observed in seven patients due to low cardiac output. There was no mid-term mortality. During follow-up, various degree of mitral regurgitation was detected in 4 patients (3.6%), regurgitation was severe in two of them and these two require reoperation with the replacement of the valve. Patients with a myxomatous valve pathology who underwent isolated valve repair most benefited from valve repair. Patients with isolated mitral stenosis were the most successful group among the patients with a rheumatic etiology. Postoperative echocardiography showed a significant decrease in the left atrial diameter and pulmonary artery systolic pressures (p<0.01).

Conclusion

Mitral valve repair can be applied as an effective and safe treatment method in patients in whom the mitral valve anatomy is sufficient for repair. We suggest that each patient with mitral valve pathology should be evaluated in terms of reparability.

Beating-Heart Mitral Valve Repair Using a Novel ePTFE Cordal Implantation Device: A Prospective Trial

BACKGROUND

Conventional mitral valve (MV) operations allow direct anatomic assessment and repair on an arrested heart, but require cardiopulmonary bypass, aortic cross-clamping, sternotomy or thoracotomy, and cardioplegic cardiac arrest, and are associated with significant perioperative disability, and risks of morbidity and mortality.

OBJECTIVES

This study evaluated safety and performance of a transesophageal echocardiographic-guided device designed to implant artificial expanded polytetrafluoroethylene (ePTFE) cords on mitral leaflets in the beating heart.

METHODS

In a prospective multicenter study, 30 consecutive patients with severe degenerative mitral regurgitation (MR) were treated with a mitral valve repair system (MVRS) via small left thoracotomy. The primary (30-day) endpoint was successful implantation of cords with MR reduction to moderate or less.

RESULTS

The primary endpoint was met in 27 of 30 patients (90%). Three patients required conversion to open mitral surgery. There were no deaths, strokes, or permanent pacemaker implantations. At 1 month, MR was mild or less in 89% (24 of 27) and was moderate in 11% (3 of 27). At 6 months, MR was mild or less in 85 % (22 of 26), moderate in 8% (2 of 26), and severe in 8% (2 of 26). Favorable cardiac remodeling at 6 months included decreases in end-diastolic (161 ± 36 ml to 122 ± 30 ml; p < 0.001) and left atrial volumes (106 ± 36 ml to 69 ± 24 ml; p < 0.001). The anterior-posterior mitral annular dimension decreased from 34.7 ± 5.8 mm to 28.2 ± 5.1 mm; p < 0.001 as did the mitral annular area (10.0 ± 2.7 cm² vs. 6.9 ± 2.0 cm²; p < 0.0001).

CONCLUSIONS

MVRS ePTFE cordal implantation can reduce the invasiveness and morbidity of conventional MV surgery. The device's safety profile is promising and prospective trials comparing the outcomes of the MVRS to conventional MV repair surgery are warranted. (CE Mark Study for the Harpoon Medical Device [TRACER]; NCT02768870).

Forward Left Ventricular Ejection Fraction: A Simple Risk Marker in Patients With Primary Mitral Regurgitation

Background

The timing of mitral valve surgery in asymptomatic patients with primary mitral regurgitation (MR) is controversial. We hypothesized that the forward left ventricular (LV) ejection fraction (LVEF; ie, LV outflow tract stroke volume divided by LV end‐diastolic volume) is superior to the total LVEF to predict outcomes in MR. The objective of this study was to examine the association between echocardiographic parameters of MR severity and LV function and outcomes in patients with MR.

Methods and Results

The clinical and Doppler‐echocardiographic data of 278 patients with ≥mild MR and no class I indication of mitral valve surgery at baseline were retrospectively analyzed. The primary study end point was the composite of mitral valve surgery or death. During a mean follow‐up of 5.4±3.2 years, there were 147 (53%) events: 96 (35%) MV surgeries and 66 (24%) deaths. Total LVEF and global longitudinal strain were not associated with the occurrence of events, whereas forward LVEF (P<0.0001) and LV end‐systolic diameter (P=0.0003) were. After adjustment for age, sex, MR severity, Charlson probability, coronary artery disease, and atrial fibrillation, forward LVEF remained independently associated with the occurrence of events (adjusted hazard ratio: 1.09, [95% confidence interval]: 1.02–1.17 per 5% decrease; P=0.01), whereas LV end‐systolic diameter was not (P=0.48).

Conclusions

The results of this study suggest that the forward LVEF may be superior to the total LVEF and LV end‐systolic diameter to predict outcomes in patients with primary MR. This simple and easily measurable parameter may be useful to improve risk stratification and select the best timing for intervention in patients with primary MR.

Basal Left Ventricular Dilatation and Reduced Contraction in Patients With Mitral Valve Prolapse Can Be Secondary to Annular Dilatation

Background—

Prominent mitral valve (MV) annular dilatation with only modest left ventricular (LV) dilatation in patients with MV prolapse (MVP) suggests predominant dilatation in adjacent basal LV, which may augment regional wall tension and attenuate contraction by Laplace’s law. We hypothesized that MV annular dilatation in patients with MVP is associated with the basal predominance of LV dilatation and attenuated contraction, which can be altered by surgical MV plasty with annulus reduction.

Methods and Results—

Echocardiography with speckle-tracking analysis to assess regional cross-sectional short-axis area and longitudinal contraction (strain) of basal, middle, and apical LV was performed in 30 controls and 130 patients with MVP. The basal value/averaged middle and apical values (B/M·A ratio) of LV cross-sectional area and strain were obtained. Patients with MVP showed significantly greater MV annular area (6.4±1.6 versus 3.7±0.6 cm 2 /m 2 ), increased B/M·A LV area ratio (2.4±0.5 versus 1.8±0.2), and reduced B/M·A LV strain ratio (0.83±0.14 versus 0.96±0.09) than controls ( P <0.001). Multivariable analyses identified that MV annular dilatation was independently associated with increased B/M·A LV area ratio (β=0.60, P <0.001), which was associated with reduced B/M·A LV strain ratio (β=−0.32, P <0.001). In 35 patients with MVP, B/M·A LV area and strain ratio significantly altered after surgical MV plasty with annulus reduction (2.5±0.5–1.8±0.3 and 0.73±0.10–0.89±0.17, P <0.001, respectively).

Conclusions—

In patients with MVP, MV annular dilatation was associated with the basal predominance of LV dilatation and reduced contraction, which can be altered by surgical MV plasty with annulus reduction, suggesting unfavorable influence from MV annular dilatation on basal LV.

Echocardiographic Follow-up of Robotic Mitral Valve Repair for Mitral Regurgitation due to Degenerative Disease

BACKGROUND

Mitral valve (MV) repair can now be carried out through small incisions with the use of robotic assistance. Previous reports have demonstrated the excellent clinical result of robotic MV repair for degenerative mitral regurgitation (MR). However, there has been limited information regarding the echocardiographic follow-up of these patients. The present study was therefore to evaluate the echocardiographic follow-up outcomes after robotic MV repair in patients with MR due to degenerative disease of the MV.

METHODS

A retrospective analysis was undertaken using data from the echocardiographic database of our department. Between March 2007 and February 2015, 84 patients with degenerative MR underwent robotic MV repair. The repair techniques included leaflet resection in 67 patients (79.8%), artificial chordae in 20 (23.8%), and ring annuloplasty in 79 (94.1%). Eighty-one (96.4%) of the 84 patients were eligible for echocardiographic follow-up assessment, and no patients were lost to follow-up.

RESULTS

At a median echocardiographic follow-up of 36.0 months (interquartile range 14.3-59.4 months), four patients (4.9%) developed recurrent mild MR, and no patients had more than mild MR. Mean MR grade, left atrial diameter (LAD), left ventricular end-diastolic diameter (LVEDD), and left ventricular ejection fraction (LVEF) were significantly decreased when compared with preoperative values. Mean MR grade decreased from 3.96 ± 0.13 to 0.17 ± 0.49 (Z = -8.456, P < 0.001), LAD from 43.8 ± 5.9 to 35.5 ± 3.8 mm (t = 15.131, P < 0.001), LVEDD from 51.0 ± 5.0 to 43.3 ± 2.2 mm (t = 14.481,P< 0.001), and LVEF from 67.3 ± 7.0% to 63.9 ± 5.1% (t = 4.585, P < 0.001).

CONCLUSION

Robotic MV repair for MR due to degenerative disease is associated with a low rate of recurrent MR, and a significant improvement in MR grade, LAD, and LVEDD, but a significant decrease in LVEF at echocardiographic follow-up.

Misconceptions and Facts About Mitral Regurgitation

Mitral regurgitation is a common heart valve disease. It is defined to be primary when it results from the pathology of the mitral valve apparatus itself and secondary when it is caused by distortion of the architecture or function of the left ventricle. Although the diagnosis and management of mitral regurgitation rely heavily on echocardiography, one should bear in mind the caveats and shortcomings of such an approach. Clinical decision making commonly focuses on the indications for surgery, but it is complex and mandates precise assessment of the mitral pathology, symptom status of the patient, and ventricular performance (right and left) among other descriptors. It is important for healthcare providers at all levels to be familiar with the clinical picture, diagnosis, disease course, and management of mitral regurgitation.

Predicting Left Ventricular Dysfunction after Surgery in Patients with Chronic Mitral Regurgitation: Assessment of Myocardial Deformation by 2-Dimensional Multilayer Speckle Tracking Echocardiography

Background and Objectives

The development of postoperative left ventricular (LV) dysfunction is a frequent complication in patients with chronic severe mitral valve regurgitation (MR) and portends a poor prognosis. Assessment of myocardial deformation enables myocardial contractility to be accurately estimated. The aim of the present study was to evaluate the predictive value of preoperative regional LV contractile function assessment using two-dimensional multilayer speckle-tracking echocardiography (2D MSTE) analysis in patients with chronic severe MR with preserved LV systolic function.

Subjects and Methods

Forty-three consecutive patients with chronic severe MR with preserved LV systolic function scheduled for mitral valve replacement (MVR) or MV repair were prospectively enrolled. Serial echocardiographic studies were performed before surgery, at 7 days follow-up, and at least 3 months follow-up postoperatively. The conventional echocardiographic parameters were analyzed. Global longitudinal strain (GLS) was obtained quantitatively by 2D MSTE.

Results

The mean age of patients was 51.7±14.3 years and 25 (58.1%) were male. In receiver-operating characteristic curve analysis, the most useful cutoff value for discriminating postoperative LV remodeling in severe MR with normal LV systolic function was -20.5% of 2D mid-layer GLS. Patients were divided into two groups by the baseline GLS -20.5%. Preoperative GLS values strongly predicted postoperative LV remodeling or LV dysfunction. The postoperative degree of decrease in LV end-diastolic dimension might be an additive predictive factor.

Conclusion

STE can be used to predict a decrease in LV function after MVR in patients with chronic severe MR. This promising method could be of use in the clinic when trying to decide upon the optimum time to schedule surgery for such patients.

Quantitation of mitral regurgitation after percutaneous MitraClip repair: comparison of Doppler echocardiography and cardiac magnetic resonance imaging

OBJECTIVE

Percutaneous valve intervention for severe mitral regurgitation (MR) using the MitraClip is a novel technology. Quantitative assessment of residual MR by transthoracic echocardiography (TTE) is challenging, with multiple eccentric jets and artifact from the clips. Cardiovascular magnetic resonance (CMR) is the reference standard for left and right ventricular volumetric assessment. CMR phase-contrast flow imaging has superior reproducibility for quantitation of MR compared to echocardiography. The objective of this study was to establish the feasibility and reproducibility of CMR in quantitating residual MR after MitraClip insertion in a prospective study.

METHODS

Twenty-five patients underwent successful MitraClip insertion. Nine were excluded due to non-magnetic resonance imaging (MRI) compatible implants or arrhythmia, leaving 16 who underwent a comprehensive CMR examination at 1.5 T (Siemens Aera) with multiplanar steady state free precession (SSFP) cine imaging (cine CMR), and phase-contrast flow acquisitions (flow CMR) at the mitral annulus atrial to the MitraClip, and the proximal aorta. Same-day echocardiography was performed with two-dimensional (2D) visualization and Doppler. CMR and echocardiographic data were independently and blindly analyzed by expert readers. Inter-rater comparison was made by concordance correlation coefficient (CCC) with 95% confidence intervals (CIs), and Bland-Altman (BA) methods.

RESULTS

Mean age was 79 years, and mean LVEF was 44%±11% by CMR and 54%±16% by echocardiography. Inter-observer reproducibility of echocardiographic visual categorical grading by expert readers was poor, with a CCC of 0.475 (-0.7, 0.74). Echocardiographic Doppler regurgitant fraction reproducibility was modest (CCC 0.59, 0.15-0.84; BA mean difference -3.7%, -38% to 31%). CMR regurgitant fraction reproducibility was excellent (CCC 0.95, 0.86-0.98; BA mean difference -2.4%, -11.9 to 7.0), with a lower mean difference and narrower limits of agreement compared to echocardiography. Categorical severity grading by CMR using published ranges had good inter-observer agreement (CCC 0.86, 0.62-0.95).

CONCLUSIONS

CMR performs very well in the quantitation of MR after MitraClip insertion, with excellent reproducibility compared to echocardiographic methods. CMR is a useful technique for the comprehensive evaluation of residual regurgitation in patients after MitraClip. Technical limitations exist for both techniques, and quantitation remains a challenge in some patients.

Mitral valve repair in asymptomatic patients with severe mitral regurgitation: pushing past the tipping point

Degenerative mitral valve regurgitation (MR) is the one of the most frequent valvular heart conditions in the Western world and is increasingly recognized as an important preventable cause of chronic heart failure. This condition also represents the most common indication for mitral surgery and is of particular interest because the mitral valve can be repaired in most patients with very low surgical risk. Historical single-center studies have supported the performance of "early mitral valve repair" in asymptomatic patients with severe degenerative MR to normalize survival and improve late outcomes. Emerging recent evidence further indicates for the first time that the prompt surgical correction of severe MR due to flail mitral leaflets within 3 months following diagnosis in asymptomatic patients without classical Class I indications (symptoms or left ventricular dysfunction) conveys a 40% decrease in the risk of late death and a 60% diminution in heart failure incidence. A 10-point rationale based on the weight of rapidly accumulating clinical data, supports the performance of early mitral valve repair even in the absence of symptoms, left ventricular dysfunction, or guideline-based triggers; when effective operations can be provided using conventional or minimally invasive techniques at very low surgical risk.