Long-term clinical and echocardiographic results after successful mitral balloon valvotomy and predictors of long-term outcome

Pulmonary vascular resistance and proper timing of percutaneous balloon mitral valvotomy

It is frequent to see pulmonary hypertension (PH) in patients with mitral stenosis (MS) secondary to increased pulmonary vascular resistance (PVR), data about the effect of PVR on the results of percutaneous balloon mitral valvotomy (PBMV) are insufficient. To detect the role of PVR in predicting residual PH immediately after PBMV. This prospective study comprised 49 consecutive patients with moderate to severe MS who were investigated pre and within 48 h post a successful PBMV for the first time. Echocardiography was used to assess the mitral valve area (MVA), mean transmitral pressure gradient (MPG), mitral valve resistance (MVR), right ventricular systolic pressure (RVSP) and PVR. Patients were classified into two groups according to the pre PVR (≥ 1.6 WU as group I and < 1.6 as group II). At baseline compared to group II (32 patients), Group I (17 patients) had higher MPG (13.6 ± 5.2 vs. 11.7 ± 3.7 mmHg, P < 0.05), RVSP (45.6 vs. 37.9 mmHg, P < 0.001) and PVR (2.2 ± 0.1 vs. 1.2 ± 0.1WU, P < 0.001) with no significant difference regarding age, gender, MVS, MVA and MVR. Patients of group I had comparatively lower improvement immediate post procedural of RVSP and PVR with no significant difference in immediate post procedural improvement in NYHA classification, MVA, MPG and MVR. Basal PVR > 1.8WU was proved to be a highly specific (91%), a good predictor (AUC 0.78) of persistent elevation of RVSP > 50 mmHg post PMV. Pathological rise of PVR that associates MS had provided a strong and an independent predictor of persistent pulmonary hypertension post PBMV and by this aspect it could be used as a valuable tool as MVA and MPG to send patients earlier for PBMV even with less severe MS. PVR > 1.81 WU could be used as a noninvasive parameter for predicting regression of PH immediately after PBMV.

Clinical and Echocardiographic Follow-up after Successful Percutaneous Transvenous Mitral Commissurotomy

Background

The objective of the study was to determine the long-term outcomes, including mitral restenosis and regurgitation, after successful percutaneous transvenous mitral commissurotomy (PTMC).

Methods

This cross-sectional prospective study was conducted at the cardiology department of Lady Reading Hospital, Peshawar, Pakistan, from January 2007 to December 2009. A total of 84 patients were followed up for a period of 96 months. Pre and post percutaneous transvenous mitral commissurotomy echocardiography was done on the mitral valve area (MVA) using two-dimensional (2D) and color doppler echocardiography. Patients who had successful PTMC were followed up for MVA loss, mitral regurgitation (MR), and cardiac death. SPSS Software (IBM SPSS Statistics for Windows, Version 22.0, Armonk, NY: IBM Corp.; 2013) was used for data analysis.

Results

Of the 84 patients, 21 were male, and 63 were females. The mean age was 35 ± 11 years. After PTMC, the mean valve two-dimensional area increased from 0.84 ± 0.13 to 1.83 ± 0.49 cm² (p value <0.001). MR was mild in 49 patients (62.8%), moderate in 27 patients (34.6%), and severe in two patients (2.6%). Good results were achieved in 60 (71.4%). Patients with good results were younger (24 ± 4), and had a relatively lower Wilkin's score, with a mean value of (8.4 ± 2.8). Follow-up events were death in six patients, mitral valve replacement (MVR) in 10 patients, and restenosis in seven patients. The Kaplan-Meier curve was used for the follow-up end points. Patient who required PTMC for mitral restenosis survived for a longer time than those requiring MVR, and those who had cardiac death due to severe pulmonary hypertension or heart failure.

Conclusion

Patients who had favorable Wilkin’s score and underwent PTMC for severe symptomatic mitral stenosis had better event-free survival in the long term follow-up.

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.

Study of Effectiveness and Safety of Percutaneous Balloon Mitral Valvulotomy for Treatment of Pregnant Patients with Severe Mitral Stenosis

INTRODUCTION

In pregnant women mitral stenosis is the commonest cardiac valvular lesion. When it is present in majorly severe condition it leads to maternal and fetal morbidity and mortality. In mitral stenosis pregnancy can lead to development of heart failure.

AIM

To evaluate the safety and efficacy of balloon mitral valvulotomy (BMV) in pregnant females with severe mitral stenosis.

MATERIALS AND METHODS

A total of 30 pregnant patients who underwent BMV were included in the study from July 2011 to November 2013. Clinical follow-up during pregnancy was done every 3 months until delivery and after delivery. The mean follow up time after BMV was 6.72±0.56 months.

RESULTS

From the 30 pregnant females 14 (46.67%) and 16 (53.3%) patients underwent BMV during the third and second trimester of pregnancy respectively. The mean mitral valve area was 0.85+0.16 cm(2) before BMV that increased to 1.60+0.27 cm(2) (p<0.0001) immediately after BMV. Peak and mean diastolic gradients had decreased significantly within 48 hours after the procedure (p<0.001) but remained very much unchanged at 6.72 month period of follow-up. Two patients had an increase in mitral regurgitation by 2 grades.

CONCLUSION

During pregnancy BMV technique is safe and effective in patients with severe mitral stenosis. This results in marked symptomatic relief along with long term maternal and fetal outcomes.

Immediate effect of percutaneous transvenous mitral commissurotomy on atrial electromechanical delay and P-wave dispersion in patients with severe mitral stenosis

BACKGROUND

Mitral stenosis (MS) is associated with prolonged inter- and intra-atrial electromechanical delays and increased P-wave dispersion, which are markers of atrial fibrillation (AF) risk. This study was conducted to assess the immediate effect of successful percutaneous transvenous mitral commissurotomy (PTMC) on these parameters.

METHODS

This single center observational study included 25 patients with severe MS (aged 34.1 ± 7.1 years, with mean mitral valve area (MVA) of 0.74 ± 0.13 cm(2)), in sinus rhythm, who underwent successful PTMC at our hospital. P-wave dispersion (PWD) was calculated by subtracting minimum P-wave duration (P min) from maximum P-wave duration (Pmax), measured on a 12-lead surface ECG obtained from each patient in supine position at a paper speed of 50mm/s and 20mm/mV. Inter-atrial (AEMD), left intra-atrial (L-IAEMD), and right intra-atrial (R-IAEMD) electromechanical delays were measured on tissue Doppler imaging. PTMC was performed using the standard Inoue Balloon technique. All these parameters were evaluated and compared before and 24-48 h after PTMC.

RESULTS

Successful PTMC led to significant reduction in AEMD (p < 0.001), L-IAEMD (p < 0.001), and R-IAEMD (p < 0.001). There were no changes in Pmax, Pmin, and PWD immediately after PTMC.

CONCLUSIONS

Successful PTMC has a favorable early impact on inter- and intra-atrial electromechanical delays, which are considered as novel parameters of atrial electromechanical remodeling in MS patients. Prospective large-scale studies are required to confirm whether improvement in these markers translates into reduced long-term AF risk.

Immediate, intermediate and long term clinical outcomes of percutaneous transvenous mitral commissurotomy

Introduction

Percutaneous transvenous mitral commissurotomy (PTMC) is one of the nonsurgical commissurotomy in patients with hemodynamically significant mitral stenosis. The aim of the present study is to assess the immediate, intermediate and long term outcomes of PTMC in relation to initial mitral valve score and to assess its impact on mitral valve area (MVA), clinical and hemodynamic parameters.

Methods

It is a retrospective study on a total of 303 patients who underwent successful PTMC between 1994 and 2001, were called back and their preprocedural, immediate post and follow-up (4, 7 and 10 year.) data were analyzed. Echo was performed in patients before and after PTMC. The patients were divided into two groups, group-I with Wilkins score of ≤ 8 and group-II with Wilkins score between 8 and 12.

Results

PTMC patients who have completed 4, 7 and 10 years of follow up revealed the mitral valve area, mean transmitral gradient and pulmonary artery pressures to be significantly different in both group-I and group-II. At all follow-up periods group-II showed higher restenosis than group-I, but its distribution between the groups was not statistically significant (χ² = 0.029; p = 0.986). Furthermore, losses of the MVA during different periods of follow-up revealed a gradual increase in attrition.

Conclusions

MV score, Mitral valve area, mitral gradient and pulmonary artery pressures appeared to influence the outcome of PTMC. A clear-cut prospective assessment of individual components of the mitral valve apparatus using 3-D echocardiographic images may provide a more precise prediction of the PTMC outcome based on its morphological abnormalities.

Twenty year follow-up after successful percutaneous balloon mitral valvuloplasty in a large contemporary series of patients with mitral stenosis

BACKGROUND

Percutaneous balloon mitral valvuloplasty (PMV) is currently considered the standard of care for suitable patients with rheumatic mitral stenosis. We sought to assess very long-term outcome after PMV.

METHODS

Between 1991 and 2010, 482 consecutive patients underwent successful PMV in a single center. Procedural success was defined as post-procedural valve area ≥ 1.5 cm(2) and regurgitation moderate or less, without in-hospital major adverse cardiac and cerebro-vascular events. The primary endpoint was 20-year incidence of major adverse cardiac events (MACE), including cardiovascular death and need for mitral surgery or repeat PMV.

RESULTS

Long-term follow-up (mean 11.6 ± 4.9 years; range 0.5 to 20) was completed in 441 (91.5%) patients. The incidence of the primary endpoint was 41.9% (95% confidence interval [CI]: 37.3 to 46.7%). The rate of cardiovascular death, need for mitral surgery or repeat PMV was 9.1% (95% CI: 6.6 to 12.1), 27% (95% CI: 22.9 to 31.4), and 5.9% (95% CI: 3.9 to 8.5), respectively. Cumulative MACE-free survival at 20 years was 35.9 ± 4.7%. At multivariate analysis, male gender (hazard ratio [HR]: 1.99; 95% CI: 1.4-2.8, p < 0.001), echocardiographic score > 8 (HR: 2.19; 95% CI: 1.6-2.9, p < 0.001), atrial fibrillation (HR: 1.54; 95% CI: 1.2-2.1, p = 0.003) and valve area ≤ 1.75 cm(2) after PMV (HR: 3.1; 95% CI: 2.3-4.2, p < 0.001) were identified as independent predictors of the primary endpoint.

CONCLUSIONS

Up to 20 years after successful PMV, a sizeable proportion of patients still exhibit a good clinical result.

The echo score revisited: Impact of incorporating commissural morphology and leaflet displacement to the prediction of outcome for patients undergoing percutaneous mitral valvuloplasty

BACKGROUND

Current echocardiographic scoring systems for percutaneous mitral valvuloplasty (PMV) have limitations. This study examined new, more quantitative methods for assessing valvular involvement and the combination of parameters that best predicts immediate and long-term outcome after PMV.

METHODS AND RESULTS

Two cohorts (derivation n=204 and validation n=121) of patients with symptomatic mitral stenosis undergoing PMV were studied. Mitral valve morphology was assessed by using both the conventional Wilkins qualitative parameters and novel quantitative parameters, including the ratio between the commissural areas and the maximal excursion of the leaflets from the annulus in diastole. Independent predictors of outcome were assigned a points value proportional to their regression coefficients: mitral valve area ≤1 cm(2) (2), maximum leaflets displacement ≤12 mm (3), commissural area ratio ≥1.25 (3), and subvalvular involvement (3). Three risk groups were defined: low (score of 0-3), intermediate (score of 5), and high (score of 6-11) with observed suboptimal PMV results of 16.9%, 56.3%, and 73.8%, respectively. The use of the same scoring system in the validation cohort yielded suboptimal PMV results of 11.8%, 72.7%, and 87.5% in the low-, intermediate-, and high-risk groups, respectively. The model improved risk classification in comparison with the Wilkins score (net reclassification improvement 45.2%; P<0.0001). Long-term outcome was predicted by age and postprocedural variables, including mitral regurgitation, mean gradient, and pulmonary pressure.

CONCLUSIONS

A scoring system incorporating new quantitative echocardiographic parameters more accurately predicts outcome following PMV than existing models. Long-term post-PMV event-free survival was predicted by age, degree of mitral regurgitation, and postprocedural hemodynamic data.

Long-Term Results up to 19 Years of Mitral Balloon Valvuloplasty

Clinical and echocardiographic data of 547 consecutive patients (mean age, 31.5 years) undergoing mitral balloon valvuloplasty with follow-up of 1.5–19 years, were analyzed. Immediately after valvuloplasty, mitral valve area increased significantly from 0.92 ± 0.17 to 1.95 ± 0.29 cm2. Restenosis occurred in 169 (31%) patients; it was less common (20%) in those with a mitral echocardiographic score ≤8. Actuarial freedom from restenosis at 10, 15, and 19 years was 78% ± 2%, 52% ± 3%, and 26 ± 4%, respectively, and significantly higher in patients with echocardiographic scores ≤8: 88% ± 2%, 67% ± 4%, and 40% ± 6%, respectively. Event-free survival at 10, 15, and 19 years was 88% ± 2%, 60% ± 4%, and 28% ± 7%, respectively, and significantly higher in patients with echocardiographic scores ≤8: 92% ± 1%, 70% ± 4%, and 42% ± 7%, respectively. Multivariate analysis identified echocardiographic score ≤8 and post-procedure valve area ≤1.8 as predictors of restenosis, and echocardiographic score > 8 and preexisting atrial fibrillation as predictors of combined events. Valvuloplasty provides excellent results in selected patients with mitral stenosis. The long-term outcome can be predicted from the baseline characteristics of the mitral valve.

Mitral stenosis

Mitral stenosis is a common disease that causes substantial morbidity worldwide. The disease is most prevalent in developing countries, but is increasingly being identified in an atypical form in developed countries. All treatments that increase valve area improve morbidity. Mortality improves with surgery; the benefit of percutaneous balloon valvuloplasty to mortality might be similar to that of surgery but needs further study. Percutaneous balloon valvuloplasty is the treatment of choice for patients in whom treatment is indicated, except for those with suboptimum valve morphology, and even these patients are sometimes treated with this procedure if surgery is not feasible or if surgical risk is prohibitive. We review the pathology, diagnosis, and treatment options for patients with mitral stenosis.

Restenosis and adverse clinical events after successful percutaneous mitral valvuloplasty: immediate post-procedural mitral valve area as an important prognosticator

AIMS

We sought to investigate the factors associated with restenosis and its potential association with late clinical deterioration after successful percutaneous mitral valvuloplasty (PMV).

METHODS AND RESULTS

We analysed echocardiographic (median 74 months) and clinical (median 109 months) follow-up data of 329 patients who achieved procedural success, defined as mitral valve area (MVA) > or =1.5 cm(2) and mitral regurgitation (MR) < or =2/4, between 1995 and 2000. Clinical events included cardiovascular death, mitral valve surgery, and repeat PMV. The 1, 3, 5, 7, and 9 year rates of restenosis-free survival were 99 +/- 1%, 97 +/- 1%, 95 +/- 1%, 86 +/- 3%, and 72 +/- 4%, respectively. The 1, 3, 5, 7, and 9 year rates of event-free survival were 99.7 +/- 0.3%, 96.4 +/- 1.0%, 94.5 +/- 1.3%, 90.8 +/- 1.6%, and 90.0 +/- 1.7%, respectively. Immediate post-PMV MVA and commissural MR or splitting, indicators of procedural adequacy, were independent predictors of both restenosis and clinical events. The best immediate post-PMV MVA cut-off value for predicting both restenosis and clinical events within 5 years after successful PMV were 1.8 cm(2) [95% confidence interval (CI) = 1.7-1.9] and 1.9 cm(2) (95% CI = 1.7-2.0), respectively. Patients with immediate post-PMV MVA <1.8 cm(2) showed significantly lower event-free survival rate than those with post-PMV MVA > or =1.8 cm(2) (P < 0.001).

CONCLUSION

Immediate post-PMV MVA> or =1.8 cm(2) was an important predictor of both restenosis- and clinical event-free survival and this value should be considered as a component of optimal result.

Evaluation of mitral stenosis in 2008

Percutaneous mitral valve commissurotomy (PMC) is the treatment of choice for patients with mitral stenosis (MS) and favorable anatomy. Evaluation of MS should answer two questions: is MS severe? And is the valve suitable for PMC? Evaluation of MS severity relies on accurate echocardiographic assessment of the mitral valve area (MVA). Several methods can be used, often in combination. The planimetry is the reference method but must be precisely performed at the tips of the leaflets in a well-oriented plane and thus requires experienced operators. New imaging technologies, such as 3D-echocardiography, MRI or computed tomography may reduce planimetry's operator dependence. The pressure half-time method (PHT) has the merit of simplicity but should be used cautiously in elderly patients or those in atrial fibrillation. It is invalid immediately after PMC but can still be used as a semi-quantitative method: a PHT less than 130 msec is associated with a good valve opening with an excellent specificity and positive predictive value whereas a PHT 130 msec does not allow any conclusion. The continuity equation, easy to perform, may be invalidated by the commonly associated aortic or mitral regurgitation or in case of atrial fibrillation. The PISA method, is reputed technically challenging and requires a direct measurement of angle between the mitral leaflets, although the use of a fixed value of 100 degrees provides an accurate MVA estimation. The main indication of transesophageal echocardiography is the exclusion of left atrial thrombus, which is a contra-indication to PMC as well as a 2/4 or greater mitral regurgitation grade. Two-dimensional-echocardiography allows detailed evaluation of valve morphology, including leaflet thickness and mobility, degree and localization of calcifications, extent of the subvalvular involvement. Unfavorable valve anatomy is associated with a lower rate of PMC success and lower event-free survival. However, given the low predictive value of all anatomic scores, the decision to perform or not the procedure should be based on a global approach taking into account not only the valve anatomy but also individual patients characteristics such as age, rhythm, NYHA class, MVA and the predicted operative mortality based on associated comorbidities.