Mitral Regurgitation After Percutaneous Mitral Valvuloplasty: Insights Into Mechanisms and Impact on Clinical Outcomes

Incidence and predictors of adverse outcomes in patients with rheumatic mitral stenosis following percutaneous balloon mitral valvuloplasty: a study from a tertiary center in Thailand

BACKGROUND

Rheumatic mitral stenosis (MS) remains a common and concerning health problem in Asia. Percutaneous balloon mitral valvuloplasty (PBMV) is the standard treatment for patients with symptomatic severe MS and favorable valve morphology. However, studies on the incidence and predictors of adverse cardiac outcomes following PBMV in Asia have been limited. This study aims to evaluate the incidence and predictors of adverse outcomes in patients with rheumatic MS following PBMV.

METHODS

A retrospective cohort study was conducted on patients with symptomatic severe MS who underwent successful PBMV between 2002 and 2020 at a tertiary academic institute in Thailand. Patients were followed up to assess adverse outcomes, defined as a composite of cardiac death, heart failure hospitalization, repeat PBMV, or mitral valve surgery. Univariable and multivariable analyses were performed to identify predictors of adverse outcomes. A p-value of < 0.05 was considered statistically significant.

RESULTS

A total of 379 patients were included in the study (mean age 43 ± 11 years, 80% female). During a median follow-up of 5.9 years (IQR 1.7-11.7), 74 patients (19.5%) experienced adverse outcomes, with an annualized event rate of 2.7%. Multivariable analysis showed that age (hazard ratio [HR] 1.03, 95% confidence interval [CI] 1.008-1.05, p = 0.006), significant tricuspid regurgitation (HR 2.17, 95% CI 1.33-3.56, p = 0.002), immediate post-PBMV mitral valve area (HR 0.39, 95% CI 0.25-0.64, p = 0.01), and immediate post-PBMV mitral regurgitation (HR 1.91, 95% CI 1.18-3.07, p = 0.008) were independent predictors of adverse outcomes.

CONCLUSIONS

In patients with symptomatic severe rheumatic MS, the incidence of adverse outcomes following PBMV was 2.7% per year. Age, significant tricuspid regurgitation, immediate post-PBMV mitral valve area, and immediate post-PBMV mitral regurgitation were identified as independent predictors of these adverse outcomes.

Assessment of suitability for percutaneous mitral commissurotomy: a contemporary review of key anatomical criteria and predictive models

The immediate result of percutaneous balloon mitral commissurotomy is largely determined by the anatomy of the mitral valve complex. Several scores and models have been developed to assess anatomical suitability for percutaneous balloon mitral commissurotomy. Although none has an optimal predictive power, these models look at the valvular apparatus from different perspectives bearing the potential for a complementary role.

Papillary muscle rupture without severe mitral regurgitation following percutaneous balloon mitral commissurotomy: a case report

Background

Percutaneous transvenous mitral commissurotomy (PTMC) is the first-line therapy of clinically significant rheumatic mitral stenosis. While the procedure is generally safe, new onset or aggravation of mitral regurgitation (MR) may occur, mainly due to commissural splitting and, less frequently, to leaflet tear and chordal rupture. Papillary muscle rupture (PMR) is exceedingly rare in this setting.

Case summary

A 74-year-old woman with a history of aortic valve replacement and prior rheumatic mitral commissurotomy presented for worsening exercise intolerance and exertional dyspnoea. Transthoracic echocardiography showed a mean pressure gradient of 10 mmHg and a mitral valve area of 1.0 cm², consistent with clinically significant mitral stenosis. Subsequent PTMC was complicated by anterolateral PMR. However, the resulting MR was unexpectedly only of mild-to-moderate severity. Because of residual mitral stenosis and persisting symptoms, surgical mechanical mitral valve replacement and tricuspid annuloplasty were performed 6 weeks after PTMC. Papillary muscle rupture was confirmed during surgery.

Discussion

We herein describe the occurrence of PMR induced by PTMC; the resulting MR was unexpectedly of mild-to-moderate severity, as a result of extensive rheumatic lesions limiting valve mobility. This case challenges the dogma according to which PMR invariably leads to severe MR. This might not be necessarily the case when it occurs following PTMC.

Outcomes of Severe Mitral Stenosis With the Revised Severity Criteria: Mitral Valve Replacement vs Percutaneous Mitral Valvuloplasty

BACKGROUND

This study aimed to compare the outcomes, according to percutaneous mitral valvuloplasty (PMV) vs mitral valve replacement (MVR), of severe mitral stenosis (MS) with the updated criteria (MVA ≤ 1.5 cm2).

METHODS

From the Multicenter Mitral Stenosis With Rheumatic Etiology (MASTER) registry of 3140 patients, we included patients with severe MS who underwent PMV or MVR between January 2000 and December 2021 except for previous valvular surgery/intervention, at least moderate other valvular dysfunction, and thrombus at the left atrium/appendage. Moderately severe MS (MS-MS) and very severe MS (VS-MS) were defined as 1.0 cm2 < MVA ≤ 1.5 cm2 and MVA ≤ 1.0 cm2, respectively. Primary outcomes were a composite of cardiovascular (CV) death and heart failure (HF) hospitalization. Secondary outcomes were a composite of primary outcomes and redo intervention.

RESULTS

Among 442 patients (mean 56.5 ±11.9 years, women 77.1%), the MVR group (n = 260) was older, had more comorbidities, higher echoscore, larger left chambers, and higher right ventricular systolic pressure than the PMV group (n = 182). During a mean follow-up of 6.9 ± 5.2 years with inverse probability-weighted matching, primary outcomes did not differ, but the MVR group experienced fewer secondary outcomes (P = 0.010). In subgroup analysis of patients with MS-MS and VS-MS, primary outcomes did not differ. However, the MVR group in patients with VS-MS showed better secondary outcomes (P = 0.012).

CONCLUSIONS

PMV or MVR did not influence CV mortality or HF hospitalization in both MS-MS and VS-MS. However, because of increased early redo intervention in the PMV group in VS-MS, MVR would be the preferable option without clear evidence of suitable morphology for PMV.

Childbearing Performances and Outcomes of Female Patients with Rheumatic Mitral Valve Diseases after Different Mitral Interventions

PURPOSE

This study aimed to illustrate how percutaneous balloon mitral valvuloplasty (PBMV) and mitral valve (MV) surgeries influence women of childbearing age with rheumatic mitral valve diseases (RMVDs) from two aspects, including clinical outcomes and their postoperative childbearing performances.

METHODS

Female patients with RMVD who were of childbearing age and underwent MV interventions between 2007 and 2019 at Beijing Anzhen Hospital were identified. Outcomes included all-cause deaths, repeated MV interventions, and atrial fibrillation. A survey about childbearing attempts and complications during pregnancy was also performed during follow-up.

RESULTS

A total of 379 patients were involved in this study, consisting of 226 cases of mitral valve replacements, 107 cases of mitral valve repairs (MVrs), and 46 cases of PBMVs. PBMV was associated with higher possibilities of repeated MV interventions (P <0.05). Postoperative childbearing attempts were more frequently observed among bioprosthesis, MVr, and PBMV (P <0.05). However, PBMV and MVr showed a higher incidence of cardiac complications during pregnancy as compared to prosthesis replacement (P <0.05).

CONCLUSIONS

MVr and PBMV are not recommended to young female patients for higher incidences of postoperative complications. Safe pregnancy is more likely to be present among patients with biological prosthesis.

Clinical Utility of Three-Dimensional Echocardiography in the Evaluation of Mitral Valve Disease: Tips and Tricks

Although real-time 3D echocardiography (RT3DE) has only been introduced in the last decades, its use still needs to be improved since it is a time-consuming and operator-dependent technique and acquiring a good quality data can be difficult. Moreover, the additive value of this important diagnostic tool still needs to be wholly appreciated in clinical practice. This review aims at explaining how, why, and when performing RT3DE is useful in clinical practice.

The 40th Anniversary of Percutaneous Balloon Valvuloplasty for Mitral Stenosis: Current Status

Percutaneous balloon mitral valvuloplasty (PBMV), once the most complex of percutaneous cardiac procedures and essentially the first adult structural heart intervention, set the stage for a host of new technologies. Randomized studies comparing PBMV to surgery were the first to provide a high-level evidence base in structural heart. The devices used have changed little in 40 years, but the advent of improved imaging and the expertise gained in interventional cardiology has provided some additional procedural safety. However, with the decline in rheumatic heart disease, PBMV is being performed in fewer patients in industrialized nations; in turn, these patients have more comorbidities, less favorable anatomy, and thus a higher rate of procedure-related complications. There remain relatively few experienced operators, and the procedure is distinct enough from the rest of the structural heart intervention world that it has its own steep learning curve. This article reviews the use of PBMV in a variety of clinical settings, the influence of anatomic and physiologic factors on outcomes, the changes in the guidelines, and alternative approaches. PBMV remains the procedure of choice in patients with mitral stenosis with ideal anatomy and a useful tool in patients with less than ideal anatomy who are poor surgical candidates. In the 40 years since its first performance, PBMV has revolutionized the care of mitral stenosis patients in developing countries and remains an important option for suitable patients in industrialized nations.

Progression of Mitral Regurgitation in Rheumatic Valve Disease: Role of Left Atrial Remodeling

Introduction

Mitral regurgitation (MR) is the most common valve abnormality in rheumatic heart disease (RHD) often associated with stenosis. Although the mechanism by which MR develops in RHD is primary, longstanding volume overload with left atrial (LA) remodeling may trigger the development of secondary MR, which can impact on the overall progression of MR. This study is aimed to assess the incidence and predictors of MR progression in patients with RHD.

Methods

Consecutive RHD patients with non-severe MR associated with any degree of mitral stenosis were selected. The primary endpoint was a progression of MR, which was defined as an increase of one grade in MR severity from baseline to the last follow-up echocardiogram. The risk of MR progression was estimated accounting for competing risks.

Results

The study included 539 patients, age of 46.2 ± 12 years and 83% were women. At a mean follow-up time of 4.2 years (interquartile range [IQR]: 1.2–6.9 years), 54 patients (10%) displayed MR progression with an overall incidence of 2.4 per 100 patient-years. Predictors of MR progression by the Cox model were age (adjusted hazard ratio [HR] 1.541, 95% CI 1.222–1.944), and LA volume (HR 1.137, 95% CI 1.054–1.226). By considering competing risk analysis, the direction of the association was similar for the rate (Cox model) and incidence (Fine-Gray model) of MR progression. In the model with LA volume, atrial fibrillation (AF) was no longer a predictor of MR progression. In the subgroup of patients in sinus rhythm, 59 had an onset of AF during follow-up, which was associated with progression of MR (HR 2.682; 95% CI 1.133–6.350).

Conclusions

In RHD patients with a full spectrum of MR severity, progression of MR occurs over time is predicted by age and LA volume. LA enlargement may play a role in the link between primary MR and secondary MR in patients with RHD.

Proinflammatory Matrix Metalloproteinase-1 Associates With Mitral Valve Leaflet Disruption Following Percutaneous Mitral Valvuloplasty

Mitral regurgitation (MR) is a major complication of the percutaneous mitral valvuloplasty (PMV). Despite high technical expertise and cumulative experience with the procedure, the incidence rate of severe MR has not decreased. Although some of MR can be anticipated by echocardiographic analysis; leaflet tearing, which leads to the most dreaded type of MR, remains unpredictable. Irregular valvular collagen remodeling is likely to compromise tissue architecture and increase the tearing risk during PMV balloon inflation. In this study, we evaluated histological and molecular characteristics of excised mitral valves from patients with rheumatic mitral stenosis (MS) who underwent emergency surgery after PMV due to severe MR caused by leaflet tear. Those findings were compared with patients who underwent elective mitral valve replacement surgery owing to severe MS, in whom PMV was not indicated. In vitro assay using peripheral blood mononuclear cells was performed to better understand the impact of the cellular and molecular alterations identified in leaflet tear mitral valve specimens. Our analysis showed that focal infiltration of inflammatory cells contributes to accumulation of MMP-1 and IFN-γ in valve leaflets. Moreover, we showed that IFN-γ increase the expression of MMP-1 in CD14⁺ cells (monocytes) in vitro. Thus, inflammatory cells contribute to unevenly remodel collagen resulting in variable thickening causing abnormalities in leaflet architecture making them more susceptible to laceration.