Temporal Trends on Percutaneous Mitral Commissurotomy: 30 Years of Experience

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.

Valvular heart disease: from mechanisms to management

Valvular heart disease is common and its prevalence is rapidly increasing worldwide. Effective medical therapies are insufficient and treatment was historically limited to the surgical techniques of valve repair or replacement, resulting in systematic underprovision of care to older patients and those with substantial comorbidities, frailty, or left ventricular dysfunction. Advances in imaging and surgical techniques over the past 20 years have transformed the management of valvular heart disease. Better understanding of the mechanisms and causes of disease and an increasingly extensive and robust evidence base provide a platform for the delivery of individualised treatment by multidisciplinary heart teams working within networks of diagnostic facilities and specialist heart valve centres. In this Series paper, we aim to provide an overview of the current and future management of valvular heart disease and propose treatment approaches based on an understanding of the underlying pathophysiology and the application of multidisciplinary treatment strategies to individual patients.

Mitral valve stenosis in the current era: a changing landscape

Mitral stenosis results from haemodynamic obstruction at the mitral valve level because of structural abnormalities of the valve apparatus, leading to increased resistance to the transmitral flow. Although rheumatic fever remains the predominant cause of mitral stenosis worldwide, other causes are increasingly relevant in the developed countries with degenerative mitral stenosis (DMS) because of mitral annulus calcification (MAC) becoming growingly prevalent in industrialized countries with higher life expectancy. Rheumatic mitral stenosis (RMS) and DMS display dramatic differences in pathophysiology, prognosis, and disease progression. Furthermore, to date, robust evidence regarding the management of DMS because of MAC is lacking. Nevertheless, new diagnostic techniques and catheter-based interventions are changing this landscape and paving the way to a significant reduction in DMS-related morbidity and mortality. Here we briefly review the current knowledge on the pathophysiology, diagnosis and treatment of DMS and RMS, underscoring the current diagnostic and therapeutic pathways, as well as persisting uncertainties and perspectives.

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.

In-hospital and Readmission Outcomes With Percutaneous Balloon Mitral Valvuloplasty

BACKGROUND

Percutaneous balloon mitral valvuloplasty (PBMV) is primarily performed for rheumatic mitral stenosis (MS). Therefore, limited data exist on PBMV in countries with a low incidence of rheumatic disease.

METHODS

Using the Nationwide Readmission Database, we examined trends in in-hospital mortality and 30-day readmission among patients who received PBMV for rheumatic and non-rheumatic MS. We also examined the change in 90-day hospitalization rate before vs. after PBMV.

RESULTS

Between 2016 and 2019, there were 1109 hospitalizations in which patients received PBMV for rheumatic (n= 955, 86.1%) vs non-rheumatic MS (n=154, 13.9%). The all-cause in-hospital mortality for rheumatic and non-rheumatic MS did not change over time (0.9% → 2.0%, p=0.94, and 5.9% → 9.5%, p=0.09 respectively). Similarly, the 30-day readmission for patients with rheumatic and non-rheumatic MS did not change over time (12.4% → 9.9%, p=0.26, and 4.4% → 10.5%, p=0.30, respectively). The 90-day all-cause hospitalization rate remained the same before vs after PBMV for rheumatic and non-rheumatic MS (25.5% → 21.8%; p=0.14, and 24.0% → 33.7%; p=0.19, respectively).

CONCLUSIONS

Although no statistically significant change was noted over time for trends in in-hospital mortality, 30-day readmission, or even in the change in 90-day all-cause hospitalizations before and after PBMV for both types of MS, among those with non-rheumatic MS, there was a signal of an increase in the in-hospital mortality, and 30-day readmission, even more, there was 29% relative increase in 90-day hospitalizations after PBMV. Future studies are needed to examine the role of PBMV in patients with non-rheumatic MS.

Timing of intervention in asymptomatic patients with valvular heart disease

Current management of valvular heart disease (VHD) seeks to optimize long-term outcome by timely intervention. Recommendations for treatment of patients with symptoms due to severe valvular disease are based on a foundation of solid evidence. However, when to intervene in asymptomatic patients remains controversial and decision requires careful individual weighing of the potential benefits against the risk of intervention and its long-term consequences. The primary rationale for earlier intervention is prevention of irreversible left ventricular (LV) myocardial changes that might result in later clinical symptoms and adverse cardiac events. A number of outcome predictors have been identified that facilitate decision-making. This review summarizes current recommendations and discusses recently published data that challenge them suggesting even earlier intervention. In adults with asymptomatic aortic stenosis (AS), emerging risk markers include very severe valve obstruction, elevated serum natriuretic peptide levels, and imaging evidence of myocardial fibrosis or increased extracellular myocardial volume. Currently, transcatheter aortic valve implantation (TAVI) is not recommended for treatment of asymptomatic severe AS although this may change in the future. In patients with aortic regurgitation (AR), the potential benefit of early intervention in preventing LV dilation and dysfunction must be balanced against the long-term risk of a prosthetic valve, a particular concern because severe AR often occurs in younger patients with a congenital bicuspid valve. In patients with mitral stenosis, the option of transcatheter mitral balloon valvotomy tilts the balance towards earlier intervention to prevent atrial fibrillation, embolic events, and pulmonary hypertension. When chronic severe mitral regurgitation is due to mitral valve prolapse, anatomic features consistent with a high likelihood of a successful and durable valve repair favour early intervention. The optimal timing of intervention in adults with VHD is a constantly changing threshold that depends not only on the severity of valve disease but also on the safety, efficacy, and long-term durability of our treatment options.

Response to: The Importance of Conscious Sedation for Life-Saving Valve Procedures in Patients With Rheumatic Heart Disease From Low- to Middle-Income Countries

A response to Alcici et al., 2019 – thinking about how using conscious sedation for percutaneous mitral commissurotomy may improve outcomes in other areas.

Percutaneous Mitral Balloon Valvuloplasty: Worldwide Trends

See Article Desnos et al

Temporal Trends on Percutaneous Mitral Commissurotomy: 30 Years of Experience

Background

Percutaneous mitral commissurotomy (PMC) was the first available transcatheter technique for treatment of mitral valve diseases. Experience has led to extending the indications to patients with less favorable characteristics. We aimed to analyze (1) the temporal trends in characteristic and outcomes of patients undergoing PMC in a single center over 30 years and (2) the predictive factors of poor immediate results of PMC.

Methods and Results

From 1987 to 2016, 1 full year for each decade was analyzed: 1987, 1996, 2006, and 2016. Poor immediate results of PMC were defined as a mitral valve area <1.5 cm² or MR (mitral regurgitation) grade >2. Mitral anatomy was assessed using the Cormier classification and the fluoroscopic extent of calcification. Six hundred three patients were included: 111, 202, 205, and 85, respectively. Mean age increased >10 years over time (P<0.0001). Mitral anatomy was less favorable over the years: the presence of calcification increased from 25% of patients at the beginning of PMC to >40% during the past decade (P<0.0001) with a 3‐fold increase in severe mitral calcification. Consistently, the proportion of good immediate results decreased over time (P<0.05) but remained at 76% in 2016. Multivariate analysis showed 3 predictive factors of poor immediate results: smaller baseline mitral valve area (P<0.0001), pre‐PMC MR grade 2 (P<0.01), and the presence or amount of calcification (P<0.001).

Conclusions

This clinic's patients became significantly older with more frequent and severe calcification in the past decade. Predictive factors of poor immediate results were related to valve anatomy, including calcification. Despite challenges raised by severe calcification, PMC was still successful in >3 out of 4 patients in recent years.

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