Update on percutaneous mitral commissurotomy

Clinical Outcomes After Valve Intervention in Rheumatic Mitral Valve Disease

Background

Rheumatic heart disease (RHD) remains one of the leading causes of mitral valve (MV) disease in developing countries. Despite the availability of percutaneous and surgical interventions, long-term outcomes remain unclear. This study aims to identify determinants of outcomes following percutaneous or surgical intervention in patients with rheumatic MV disease, addressing critical gaps in treatment selection.

Methods

A retrospective, intention-to-treat study was conducted on patients with symptomatic rheumatic MV disease, primarily characterized by mitral stenosis, who underwent either percutaneous mitral valvuloplasty (PMV) or MV replacement (MVR). Demographic, clinical, and echocardiographic variables were collected. The long-term outcome was defined as a composite of death, repeat PMV, need for cardiac surgery, and stroke.

Results

A total of 246 patients were enrolled (mean age 43.8 ± 13 years, 80% women, with 45% in New York Heart Association [NYHA] class III/IV). Of these, 90 patients (37%) underwent MVR, while 156 patients (63%) underwent PMV, with similar clinical characteristics at baseline. During a mean follow-up of 2.8 years, ranging from 1 day to 7.8 years, 45 patients (18%) reached the composite outcome, including 11 deaths (4%). Long-term outcomes were comparable between PMV and MVR (P = 0.231). Independent predictors of composite outcomes included baseline NYHA class III/IV (adjusted hazard ratio [HR] 2.10, 95% confidence interval [CI] 1.10-4.11, P = 0.023) and older age (HR 1.03, 95% CI 1.01-1.06, p = 0.020). Predictors of all-cause mortality following either PMV or MVR were older age (HR 1.08, 95% CI 1.03-1.14, P = 0.002) and lower left ventricular ejection fraction (HR 0.93, 95% CI 0.88-0.99, P = 0.021).

Conclusions

This study identified older age and higher NYHA functional class as significant predictors of composite outcomes in patients with rheumatic MV disease requiring intervention. Left ventricular systolic dysfunction was independently associated with increased mortality following both percutaneous and surgical intervention. Long-term outcomes were comparable between patients undergoing PMV and MVR, reinforcing PMV as an effective alternative to surgery in appropriately selected patients.

Unveiling the Group A Streptococcus Vaccine-Based L-Rhamnose from Backbone of Group A Carbohydrate: Current Insight Against Acute Rheumatic Fever to Reduce the Global Burden of Rheumatic Heart Disease

Group A Streptococcus (GAS) is a widely distributed bacterium that is Gram-positive and serves as the primary cause of acute rheumatic fever (ARF) episodes. Rheumatic heart disease (RHD) is a sequela resulting from repeated ARF attacks which are also caused by repeated GAS infections. ARF/RHD morbidity and mortality rates are incredibly high in low- and middle-income countries. This is closely related to poor levels of sanitation which causes the enhanced incidence of GAS infections. Management of carditis in RHD cases is quite challenging, particularly in developing countries, considering that medical treatment is only palliative, while definitive treatment often requires more invasive procedures with high costs. Preventive action through vaccination against GAS infection is one of the most effective steps as a solution in reducing RHD morbidity and mortality due to curative treatments are expensive. Various developments of M-protein-based GAS vaccines have been carried out over the last few decades and have recently begun to enter the clinical stage. Nevertheless, this vaccination generates cross-reactive antibodies that might trigger ARF assaults as a result of the resemblance between the M-protein structure and proteins found in many human tissues. Consequently, the development of a vaccine utilizing L-Rhamnose derived from the poly-rhamnose backbone of Group A Carbohydrate (GAC) commenced. The L-Rhamnose-based vaccine was chosen due to the absence of the Rhamnose biosynthesis pathway in mammalian cells including humans thus this molecule is not found in any body tissue. Recent pre-clinical studies reveal that L-Rhamnose-based vaccines provide a protective effect by increasing IgG antibody titers without causing cross-reactive antibodies in test animal tissue. These findings demonstrate that the L-Rhamnose-based vaccine possesses strong immunogenicity, which effectively protects against GAS infection while maintaining a significantly higher degree of safety.

Feasibility and Exploration of a Standardized Protocol for Cardiac CT Assessment of Rheumatic Mitral Disease

Rheumatic mitral valve disease often requires surgical interventions, such as percutaneous mitral commissurotomy, surgical mitral valve repair, or replacement, especially in severe cases. This necessitates a precise preoperative assessment of the extent of mitral valve disease. Currently, transthoracic echocardiography, the gold standard for preoperative assessment, has limitations, such as restricted acoustic windows and dependence on the operator, which can affect the evaluation of subvalvular structures and calcification of the mitral valve. Previous studies have shown that cardiac computed tomography (CT), with its high resolution, strong multiplanar reconstruction capabilities, and sensitivity to calcifications, can effectively overcome these limitations. Therefore, this study aims to summarize and evaluate the effectiveness of cardiac CT in examining mitral valve leaflets, annulus, and subvalvular structures. It also reviews the feasibility and guiding significance of using cardiac CT to assess characteristic rheumatic mitral valve lesions.

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.

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.

In-hospital outcomes of patients undergoing concomitant aortic and mitral valve replacement in Germany

 

OBJECTIVES

To evaluate in-hospital outcomes of concomitant mitral valve replacement (MVR) in patients undergoing conventional aortic valve replacement due to aortic stenosis in a nationwide cohort.

METHODS

Administrative data from all patients with aortic stenosis undergoing conventional aortic and concomitant MVR (reason for MVR not specified) between 2017 and 2018 in Germany were analysed.

RESULTS

A total of 2597 patients with a preoperative logistic EuroScore of 9.81 (standard deviation: 8.56) were identified. In-hospital mortality was 6.8%. An in-hospital stroke occurred in 3.4%, acute kidney injury in 16.3%, prolonged mechanical ventilation of more than 48 h in 16.3%, postoperative delirium in 15.8% and postoperative pacemaker implantation in 7.6% of the patients. Mean hospital stay was 16.5 (standard deviation: 12.1) days. Age [odds ratio (OR): 1.03; P = 0.019], New York Heart Association class III or IV (OR: 1.63; P = 0.012), previous cardiac surgery (OR: 2.85, P = 0.002), peripheral vascular disease (OR: 2.01, P = 0.031), pulmonary hypertension (OR: 1.63, P = 0.042) and impaired renal function (glomerular filtration rate <15, OR: 3.58, P = 0.001; glomerular filtration rate <30, OR: 2.51, P = 0.037) were identified as independent predictors for in-hospital mortality.

CONCLUSIONS

In this nationwide analysis, concomitant aortic and MVR was associated with acceptable in-hospital mortality, morbidity and length of in-hospital stay. The regression analyses may help to identify high-risk patients and further optimize treatment strategies.

The Global Impact of Rheumatic Heart Disease

PURPOSE OF REVIEW

Rheumatic heart disease (RHD) is a neglected disease of poverty, which presents challenges for patients, communities, and health systems. These effects are magnified in low resource countries, which bear the highest disease burden. When considering the impact of RHD, it is imperative that we widen our lens in order to better understand how RHD impacts the over 40 million people currently living with this preventable condition and their communities. We aimed to perform an updated literature review on the global impact of RHD, examining a broad range of aspects from disease burden to impact on healthcare system to socioeconomic implications.

RECENT FINDINGS

RHD accounts for 1.6% of all cardiovascular deaths, resulting in 306,000 deaths yearly, with a much higher contribution in low- and middle-income countries, where 82% of the deaths occurred in 2015. RHD can result in severe health adverse outcomes, markedly heart failure, arrhythmias, stroke and embolisms, and ultimately premature death. Thus, preventive, diagnostic and therapeutic interventions are required, although insufficiently available in undersourced settings. As examples, anticoagulation management is poor in endemic regions - and novel oral anticoagulants cannot be recommended - and less than 15% of those in need have access to interventional procedures and valve replacement in Africa. RHD global impact remains high and unequally distributed, with a marked impact on lower resourced populations. This preventable disease negatively affects not only patients, but also the societies and health systems within which they live, presenting broad challenges and high costs along the pathway of prevention, diagnosis, and management.

Transcatheter mitral valve therapies: State of the art

Mitral regurgitation (MR) is one of the most prevalent valvular pathologies in the developed world. There continues to be a growing population of aging patients with MR who may be too high risk for surgical management. The rapid adoption and remarkable success of transcatheter aortic valve replacement (TAVR) generated enthusiasm for transcatheter mitral valve therapies; however, the complex anatomy and pathophysiology of the mitral valve confers several unique challenges for a fully percutaneous approach. Nevertheless, several devices are under development and in various phases of preclinical or clinical testing, both for transcatheter mitral valve replacement and repair. MitraClip (Abbott Vascular), which has received FDA approval, is the most established percutaneous repair strategy and has been performed in over 80,000 patients as of 2019. The following article serves as a review of the available and upcoming devices for the various etiologies of mitral valvular disease, as well as the unique challenges and potential complications of transcatheter mitral valve intervention.

Pulmonary artery pressure response to percutaneous mitral valvuloplasty: Associated factors and clinical implications

BACKGROUND

Pulmonary hypertension (PH) is a marker of poor outcome in mitral stenosis (MS), which improves after percutaneous mitral valvuloplasty (PMV). However, mechanical interventions for relief of valve obstruction often but not always reduce pulmonary pressures. This study aimed to assess the parameters associated with abnormal pulmonary artery pressure (PAP) response immediately after a successful PMV, and also its impact on long-term outcome.

METHODS

A total of 181 patients undergoing PMV for rheumatic MS were prospectively enrolled. Invasive hemodynamic and echocardiographic measures were examined in all patients. Abnormal PAP response was defined as the mean PAP (mPAP) values unchanged at the end of the procedure. Long-term outcome was a composite endpoint of death, mitral valve replacement, repeat PMV, new onset of atrial fibrillation (AF), or stroke.

RESULTS

The mean age was 44.1 ± 12.6 years, and 157 patients were women (86.7%). In the overall population, mPAP decreased from 33.4 ± 13.1 mmHg pre to 27.6 ± 9.8 mmHg post (p < 0.001). Following PMV, 52 patients (28.7%) did not have any reduction of mPAP immediately after the PMV. Multivariable analysis adjusting for baseline values of PAP and mitral valve area revealed that AF (Odds ratio [OR] 2.7, 95% [confidence interval] CI 1.3 to 6.7), maximum mitral valve leaflets displacement (OR 0.8, 95% CI 0.7 to 0.9), and post-procedural left ventricular compliance (OR 0.7, 95% CI 0.5 to 0.9) were predictors of a lack of improvement in mPAP. During a median follow-up of 4.4 years, the endpoint was reached in 56 patients (31%). The pulmonary pressure response to PMV was not an independent predictor of long-term events.

CONCLUSIONS

In patients with MS undergoing PMV, pulmonary pressures may not reduce immediately after the procedure, despite adequate opening of the valve. Abnormal PAP response can be predicted from baseline clinical and valvular characteristics as well as post-procedural left ventricular compliance. The lack of any immediate reduction in mPAP is not associated with long-term adverse outcomes.

Mid-term (up to 12 years) clinical and echocardiographic outcomes of percutaneous transvenous mitral commissurotomy in patients with rheumatic mitral stenosis

Background

Rheumatic heart disease (RHD) is still a concerning issue in developing countries. Among delayed RHD presentations, rheumatic mitral valve stenosis (MS) remains a prevalent finding. Percutaneous transvenous mitral commissurotomy (PTMC) is the intervention of choice for severe mitral stenosis (MS). We aimed to assess the mid-term outcome of PTMC in patients with immediate success.

Methods

In this retrospective cohort study, out of 220 patients who had undergone successful PTMC between 2006 and 2018, the clinical course of 186 patients could be successfully followed. Cardiac-related death, undergoing a second PTMC or mitral valve replacement (MVR) were considered adverse cardiac events for the purpose of this study. In order to find significant factors related to adverse cardiac outcomes, peri-procedural data for the studied patients were collected.The patients were also contacted to find out their current clinical status and whether they had continued secondary antibiotic prophylaxis regimen or not. Those who had not suffered from the adverse cardiac events were additionally asked to undergo echocardiographic imaging, in order to assess the prevalence of mitral valve restenosis, defined as mitral valve area (MVA) < 1.5 cm² and loss of ≥ 50% of initial area gain.

Results

During the mean follow-up time of 5.69 ± 3.24 years, 31 patients (16.6% of patients) had suffered from adverse cardiac events. Atrial fibrillation rhythm (p = 0.003, HR = 3.659), Wilkins echocardiographic score > 8 (p = 0.028, HR = 2.320) and higher pre-procedural systolic pulmonary arterial pressure (p = 0.021, HR = 1.031) were three independent predictors of adverse events and immediate post-PTMC mitral valve area (IMVA) ≥ 2 cm² (p < 0.001, HR = 0.06) was the significant predictor of event-free outcome. Additionally, follow-up echocardiographic imaging detected mitral restenosis in 44 patients (23.6% of all patients). The only statistically significant protective factor against restenosis was again IMVA ≥ 2 cm² (p = 0.001, OR = 0.240).

Conclusion

The mid-term results of PTMC are multifactorial and may be influenced by heterogeneous peri-procedural determinants. IMVA had a great impact on the long-term success of this procedure. Continuing secondary antibiotic prophylaxis was not a protective factor against adverse cardiac events in this study. (clinicaltrial.gov registration: NCT04112108).

Supplementary Information

The online version contains supplementary material available at 10.1186/s12872-021-02175-3.

Decreased Cytokine Plasma Levels and Changes in T-Cell Activation Are Associated With Hemodynamic Improvement and Clinical Outcomes After Percutaneous Mitral Commissurotomy in Patients With Rheumatic Mitral Stenosis

Mitral stenosis (MS) is a consequence of rheumatic heart disease that leads to heart failure requiring mechanical intervention. Percutaneous mitral commissurotomy (PMC) is the treatment of choice for the intervention, and currently there are no soluble markers associated with hemodynamic improvement after PMC. This study aims to determine the changes in cytokine/chemokine plasma levels, as well as T cell activation after PMC, and to investigate their association with immediate hemodynamic improvement and clinical outcomes. Plasma samples from eighteen patients with well-defined MS who underwent PMC and 12 healthy controls were analyzed using BioPlex immunoassay. We observed that 16 out of the 27 (60%) molecules assessed were altered in patients' plasma pre-PMC as compared to control group. Of those, IL-1β, IL-12, IL-6, IL-4, PDGF, and CCL11 showed significant decrease after PMC. Stratifying the patients according to adverse outcome after a 28-month median follow up, we detected a significant reduction of IL-1β, IL-12, IL-6, IL-4, IFN-γ, CXCL-10, VEGF, FGF and PDGF post-PMC in patients without events, but not in those who presented adverse events during the follow-up. Patients with adverse outcomes had lower IL-10 pre-PMC, as compared to the ones without adverse events. In addition, the frequency of CD8+ activated memory cells was increased after PMC, while the frequency of CD4+ activated memory cells did not change. Our results show an association between the decrease of specific cytokines and changes in T cell activation with hemodynamic improvement post-PMC, as well as with long-term outcomes, suggesting their possible use as soluble markers for hemodynamic recovery after MS intervention.

Atrial Fibrillation in Valvular Heart Disease

Rheumatic heart disease results in significant remodeling of the atria that provides the milieu for maintaining atrial fibrillation. Some electrical remodeling is reversible and hence early intervention may prove useful. Active screening for atrial fibrillation in high-risk subset and instituting anticoagulation may reduce the devastating complications that follow. Age older than 50 years, NYHA functional class II symptoms, left atrial dimension >4.0 cm on echocardiogram in parasternal long-axis view, and gradients across the mitral valve >10 mm Hg are clinical indicators that identify the high-risk subset. Ablation strategy in this population may differ compared with the nonvalvular group.

Raising awareness for rheumatic mitral valve disease

Rheumatic heart disease (RHD) is a major burden in low- to mid-income countries, where each year it accounts for over a million premature deaths associated with severe valve disease. Life-saving valve replacement procedures are not available to the majority of affected RHD patients, contributing to an increased risk of death in young adults and creating a devastating impact. In December 2017, a group of representatives of major cardiothoracic societies and industry, discussed the plight of the millions of patients who suffer from RHD. A comprehensive solution based on this global partnership was outlined in "The Cape Town Declaration on Access to Cardiac Surgery in the Developing World". The key challenge in controlling RHD is related to identification and removal of barriers to the translation of existing knowledge into policy, programs, and practice to provide high-quality care for patients with RHD. This review provides an overview on RHD by emphasizing the disease medical and economic burdens worldwide, risk factors, recent advance for early disease detection, and overall preventive strategies.

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

OBJECTIVES

The aim of this study was to assess the incidence, mechanisms, and outcomes of mitral regurgitation (MR) after percutaneous mitral valvuloplasty (PMV).

BACKGROUND

Significant MR continues to be a major complication of PMV, with a wide range in clinical presentation and prognosis.

METHODS

Consecutive patients with mitral stenosis undergoing PMV were prospectively enrolled. MR severity was evaluated by using quantitative echocardiographic criteria, and its mechanism was characterized by 3-dimensional transesophageal echocardiography, divided broadly into 4 categories based on the features contributing to the valve damage. B-type natriuretic peptide levels were obtained before and 24 h after the procedure. Endpoints estimated cardiovascular death or mitral valve (MV) replacement due to predominant MR.

RESULTS

A total of 344 patients, ages 45.1 ± 12.1 years, of whom 293 (85%) were women, were enrolled. Significant MR after PMV was found in 64 patients (18.6%). The most frequent mechanism of MR was commissural, which occurred in 22 (34.4%) patients, followed by commissural with posterior leaflet in 16 (25.0%), leaflets at central scallop or subvalvular damage in 15 (23.4%), and central MR in 11 (17.2%). During the mean follow-up period of 3 years (range 1 day to 10.6 years), 60 patients reached the endpoint. The event-free survival rates were similar among patients with mild or commissural MR, whereas patients with damaged central leaflet scallop or subvalvular apparatus had the worst outcome, with an event-free survival rate at 1 year of only 7%. Long-term outcome was predicted by net atrioventricular compliance (C_n) at baseline and post-procedural variables, including valve area, mean gradient, and magnitude of decrease in B-type natriuretic peptide levels, adjusted for the mechanism of MR.

CONCLUSIONS

Significant MR following PMV is a frequent event, mainly related to commissural splitting, with favorable clinical outcome. Parameters that express the relief of valve obstruction and the mechanism by which MR develops were predictors of long-term outcomes.

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

BACKGROUND

Severe valve disease, which requires intervention, remains strongly associated with mortality in patients with rheumatic heart disease. Percutaneous mitral commissurotomy (PMC) is the procedure of choice for the treatment of patients with isolated or predominantly rheumatic mitral stenosis. This procedure has been performed under sedation to avoid the potential effects of general anesthesia on intracardiac pressure measurements. However, there are limited data on sedation during PMC, especially using easily available medications in low- and middle-income countries.

OBJECTIVES

This study was designed to evaluate the efficacy and hemodynamic effects of conscious sedation during PMC in patients with significant mitral stenosis.

METHODS

This study prospectively enrolled 23 patients who underwent PMC with the Inoue balloon technique for hemodynamically significant mitral stenosis. For conscious sedation, midazolam 25 μg/kg and fentanyl 1 μg/kg were administered, and 5 min after the infusion, the level of sedation was evaluated by Ramsay sedation scale. A range of invasive hemodynamic measurements, including cardiac output and pulmonary artery pressures, were recorded before and immediately after sedation.

RESULTS

The mean age was 44.9 ± 10.8 years, and 19 patients (83%) were women. After sedation, the majority of patients were in categories 2 and 3 of the Ramsay sedation scale (cooperative, orientated, tranquil, and responding to commands). Oxygen saturation dropped from an average of 98.5% to 96.0% without supplementary oxygen. Left ventricular systolic pressure and central aortic pressures decreased after sedation. However, none of the other parameters changed significantly after sedation, including pulmonary artery pressures, pulmonary vascular resistance, and cardiac index.

CONCLUSIONS

This simple model of conscious sedation was able to promote anxiolysis, analgesia, and comfort for the procedure without serious hemodynamic effects, which can be a reasonable choice in developing countries.

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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Assessment of quality of life before and after successful percutaneous transvenous mitral commissurotomy in patients with severe mitral stenosis

BACKGROUND

Rheumatic mitral stenosis (MS) is a significant cause of morbidity and mortality in India. Percutaneous transvenous mitral commissurotomy (PTMC) has become the procedure of choice for severe MS with pliable leaflets. Despite a wealth of literature on the technical aspects of PTMC, there is a dearth of literature addressing the impact of PTMC on the quality of life (QOL).

AIM

The aim of the study is to assess the impact of PTMC on clinical status and QOL of patients with severe MS.

MATERIALS AND METHODS

Twenty-five consecutive patients with severe MS undergoing PTMC were included in the study with their informed consent. All patients were subjected to routine blood tests, electrocardiogram, chest X-ray, two-dimensional and color echocardiography, treadmill test (TMT), and World Health Organization (WHO) QOL scale. The echocardiography, TMT, and WHOQOL scale were repeated after the procedure.

RESULTS

The procedural success was 98%. The mean (range) mitral valve area preprocedure was 0.82 (0.59-0.92) cm² and postprocedure was 1.61 (1.51-1.76) cm². The difference was statistically significant (t = 5.02; P < 0.01). The mean (range) of TMT preprocedure was 4.05 (3.0-7.0) METS and postprocedure was 8.52 (6-12) METS. The difference was statistically significant (T = 3.08; P < 0.01). The mean (range) of QOL assessment pre- and post-procedure on physical domain was 8.83 (8.3-10.1) which increased to 11.11 (10-12.7); on social relationship domain from 9.17 (7.5-12.4) to 11.37 (9.4-12.0); on personal relationship from 11.6 (11-13) to 12.52 (12-13); on environment domain from 10.78 (10.2-11.7) to 11.56 (10.8-12); and on level of independence from 9.02 (8-10) to 12.29 (11.0-13.6). All the differences were statistically significant (Wilcoxon signed-rank test z = -4.376; -4.379; -4.234; -4.200; -4.375; respectively, all P < 0.001 highly significant).

CONCLUSIONS

PTMC resulted in a significant improvement in the QOL of patients with severe MS. The significant improvement in QOL post-PTMC may be an indication for offering PTMC at an earlier stage to those patients whose QOL is severely compromised.

Impact of left atrial compliance improvement on functional status after percutaneous mitral valvuloplasty

BACKGROUND

Conventional hemodynamic parameters may not accurately predict symptomatic improvement after percutaneous mitral valvuloplasty (PMV). Changes in left heart chamber compliance following adequate relief o0066 mitral stenosis (MS) may be useful in determining functional capacity after PMV. This study aims to determine the acute effects of PMV on compliance of the left heart and whether its changes relate to the patient's functional capacity.

METHODS

One-hundred thirty-seven patients with severe MS undergoing PMV were enrolled. Left atrial (C_a ) and left ventricular (C_v ) compliance were invasively estimated and net atrioventricular compliance (C_av ) was calculated before and immediately after the procedure. B-type natriuretic peptide (BNP) levels were obtained before and 24 hr after the procedure. The primary endpoint was functional status at 6-month follow-up, and the secondary endpoint was a composite of death, mitral valve (MV) replacement, repeat PMV, new onset of atrial fibrillation, or stroke in patients in whom PMV was successful.

RESULTS

The mean age was 43 ± 12 years, and 119 patients were female (87%). After PMV, C_a and C_av improved significantly from 5.3 [IQR 3.2-8.2] mL/mmHg to 8.7 [5.3-19.2] mL/mmHg (P < 0.001) and 2.2 [1.6-3.4] to 2.8 [2.1-4.1] mL/mmHg (P < 0.001), respectively, whereas C_v did not change (4.6 [3.2-6.8] to 4.4 [3.1-5.6]; P = 0.637). Plasma BNP levels significantly decreased after PMV, with no correlation between its variation and changes in left chamber compliance. At 6-month follow-up, NYHA functional class remained unchanged in 32 patients (23%). By multivariable analyses, changes in C_a immediately after PMV (adjusted OR 1.42; 95% CI 95% 1.02 to 1.97; P = 0.037) and younger age (adjusted OR 0.95; CI 95% 0.92-0.98; P = 0.004), predicted improvement in functional capacity at 6-month follow-up, independent of postprocedural data. The secondary endpoint were predicted by post-PMV mean gradient (adjusted HR 1.363; 95% CI 95% 1.027-1.809; P = 0.032), and lack of functional improvement at 6-month follow-up (adjusted HR 4.959; 95% 1.708-14.403; P = 0.003).

CONCLUSIONS

C_a and C_av increase significantly after PMV with no change in C_v . The improvement of C_a is an important predictor of functional status at 6-month follow up, independently of other hemodynamic data. Postprocedural mean gradient and lack of short-term symptomatic improvement were predictors of adverse outcome.

Management of atrial fibrillation in patients with rheumatic mitral stenosis

Atrial fibrillation (AF) is frequent in patients with rheumatic mitral stenosis (MS). Pressure overload leads to marked structural and electrical remodelling of left atrium. The frequency of persistent AF increases with age and paroxysmal, asymptomatic, AF seems even more frequent. The occurrence of AF worsens the haemodynamic tolerance of MS and markedly increases the risk of thromboembolic events. AF has a negative impact on the natural history of MS and on its outcome after commissurotomy. The respective indications of rhythm and rate control should be adapted to patient characteristics, particularly the consequences of MS, and take into account the high risk of recurrence of AF. Oral anticoagulant therapy is mandatory when AF complicates MS, regardless of its severity and CHA2DS2-VASc score. Non-vitamin K antagonists oral anticoagulants are not recommended in moderate-to-severe MS due to the lack of data. Percutaneous mitral commissurotomy does not appear to prevent the occurrence of AF in MS but should be considered as the first-line therapy when AF is associated with severe symptomatic MS, followed by the discussion of cardioversion or ablation. AF ablation should be considered in patients with mitral disease requiring intervention, but the ideal timing and techniques are difficult to determine due to the lack of appropriate specific randomised trials in patients with MS.

Net atrioventricular compliance is an independent predictor of cardiovascular death in mitral stenosis

OBJECTIVES

Rheumatic mitral stenosis (MS) is a progressive disease, and risk of death may persist despite relief of the obstruction. Net atrioventricular compliance (C_n) modulates the overall haemodynamic burden of the MS and may be useful in predicting cardiovascular death after percutaneous mitral valvuloplasty (PMV).

METHODS

A total of 427 patients (mean age 50±16 years, 84% female) with severe MS undergoing PMV were enrolled. Doppler-derived C_n was estimated at baseline using a previously validated equation. The primary endpoint was late cardiovascular death, and the secondary endpoint was a composite of all-cause mortality, mitral valve (MV) replacement or repeat PMV over a median follow-up of 31 months (IQR: 7.8-49.2 months).

RESULTS

At baseline, 209 patients (49%) were in New York Heart Association (NYHA) functional class III or IV. During follow-up, 49 patients died (41 cardiovascular deaths), 50 underwent MV replacement and 12 required repeat PMV, with an overall incidence of cardiac mortality and adverse events of 4.1 deaths and 11.1 events per 100 patient-years, respectively. Low baseline C_n was a strong predictor of both cardiac death (adjusted HR 0.70, 95% CI 0.49 to 0.86) and composite endpoint (adjusted HR 0.81, 95% CI 0.67 to 0.91) after adjusting for clinical factors, baseline pulmonary artery pressure, tricuspid regurgitation severity, right ventricular function and immediate procedural haemodynamic data. The inclusion of C_n in a model with conventional parameters resulted in improvement in 5-year cardiovascular mortality risk prediction.

CONCLUSIONS

Baseline C_n is a strong predictor of cardiovascular death in patients with MS undergoing PMV, independent of other prognostic markers of decreased survival in MS, including baseline patient characteristics and postprocedural data. C_n assessment therefore has potential value in evaluation of cardiovascular mortality risk in the setting of MS.

Impact of percutaneous mitral valvuloplasty on left ventricular function in patients with mitral stenosis assessed by 3D echocardiography

BACKGROUND

The status of intrinsic left ventricular (LV) contractility in patients with isolated rheumatic mitral stenosis (MS) has been debated. The acute changes in loading conditions after percutaneous mitral valvuloplasty (PMV) may affect LV performance. We aimed to examine the acute effects of PMV on LV function and identify factors associated with LV ejection fraction (LVEF) changes, and determinants of long-term events following the procedure.

METHODS

One hundred and forty-two patients who underwent PMV for symptomatic rheumatic MS (valve area of 0.99±0.3cm²) were prospectively enrolled. LV volumes and LVEF were measured by three-dimensional (3D) echocardiography. Long-term outcome was a composite endpoint of death, mitral valve (MV) replacement, repeat PMV, new onset of atrial fibrillation, and stroke.

RESULTS

The mean age was 42.3±12.1years, and 125 patients were women (88%). After PMV, LVEF increased significantly (51.4 vs 56.5%, p<0.001), primary due to a significant increase in LV end-diastolic volume (65.8mL vs 67.9mL, p=0.002), and resultant increase in the stroke volume (33.9mL vs 39.6mL, p<0.001). Changes in cardiac index and systolic pulmonary artery pressure were associated with LVEF changes after PMV. During a mean follow-up period of 30.8months, 28 adverse clinical events were observed. Postprocedural mitral regurgitation, MV area, and mean gradient were independent predictors of composite endpoints.

CONCLUSIONS

In patients with rheumatic MS, PMV resulted in a significant improvement in LV end-diastolic volume, stroke volume and consequently increased in LVEF. Changes in cardiac index and systolic pulmonary artery pressure were associated with LVEF changes after PMV. The predictors of long-term adverse events following PMV were post-procedural variables, including mitral regurgitation, valve area, and mean gradient.