Favorable effect of balloon mitral valvuloplasty on the incidence of atrial fibrillation in patients with severe mitral stenosis

Immediate And Long Term Effects Of Percutaneous Mitral Balloon Valvuloplasty On Atrial Conduction Velocities In Patients With Mitral Stenosis

Background

P-wave dispersion (PWD) is an electrocardiographic (ECG) marker of nonuniform and heterogeneous atrial conduction with ECG leads of different orientation. The aim of our study was to investigate the immediate and long term effects of successful percutaneous mitral balloon valvuloplasty (PMBV) on PWD in severe rheumatic MS patients and to analyse the restenosis, atrial fibrillation (AF) and redo balloon valvuloplasty rate.

Methods

We enrolled 41 consecutive MS patients with sinus rhythm who underwent PMBV. A 12-lead ECG and transthoracic echocardiography were performed for each patient one day before, within 72 hours after the procedure and followed up by clinical visit at a mean of 5,57±1,46 (3-8) year.The mean patient age was 44.1±10.86 years.

Results

Pmax 1(pre PMBV) and PWD 1(pre PMBV) decreased 1-3 days after PMBV. MVA improved immediately after the procedure; but lately the mean MVA decreased significantly indicating the initiation of restenosis. Composite endpoints were associated with LA 1 (p = 0.02), MVA 2 (1-3 days after PMBV) (p= 0.019), mean gradient 2 (p= 0.028), PWD 3 (3 years after PMBV) (p < 0.001) and Pmax 3 (3 years after PMBV) (<0,001). AF incidence was associated with PWD 2 (p=0,019) and PWD 3 (p=0,010). There was 14 composite endpoint on follow up and at multivariate analysis PWD 3 was identified as an independent predictor of the composite endpoint (p=0.048, hazard ratio=1.36, 95% confidence interval (CI): 1,002-1.867).

Conclusions

This study has demonstrated that Pmax and PWD significantly decreased within 3 days after PMBV. Furthermore, long term PWD was associated with AF and identified as an independent predictor of the composite endpoint.

Sinus Rhythm in Rheumatic Mitral Stenosis after Balloon Mitral Valvotomy: Is it Feasible?

INTRODUCTION

Atrial Fibrillation (AF) is largely present in patients with rheumatic valvular disease, leading to hospitalizations.

AIM

We aimed to study the restoration and maintenance of Sinus Rhythm (SR) in rheumatic patients with Mitral Stenosis (MS) and AF after Balloon Mitral Valvotomy (BMV) and evaluated the factors which affect the maintenance of SR.

MATERIALS AND METHODS

A total of 50 patients who underwent BMV at U. N. Mehta Institute of Cardiology and Research Centre from 2010 November to 2013 January were included in the study. Subsequently, all patients were treated with amiodarone and electrical cardioversion was applied in patients in whom it was necessary. The patients were followed for six months for conversion and maintenance of SR.

RESULTS

Total 34 (68%) patients reverted to SR. Twelve patients reverted to SR with amiodarone and 22 patients with electrical cardioversion and amiodarone. Out of the total, 29 patients and 26 patients remained in SR at the end of follow up at 3 months and 6 months respectively.

CONCLUSION

Smaller Left Atrial (LA) size and greater Mitral Valve Area (MVA) are the chief predictors of restoration and maintenance of SR. Combining BMV with an aggressive anti-arrhythmic strategy offers the best prospect of rhythm control.

Usefulness of the Macruz Index for Predicting Successful Percutaneous Mitral Balloon Valvuloplasty in Patients with Mitral Stenosis

OBJECTIVE

The aim of this study was to determine whether the Macruz index (P/P-R segment) could predict the severity of valvular involvement and the success of percutaneous mitral balloon valvuloplasty (PMBV) in patients with mitral stenosis (MS).

SUBJECTS AND METHODS

Sixty-one patients with MS eligible for PMBV and 72 healthy subjects (61 females and 11 males) with sinus rhythm were enrolled into this study. PMBV was performed in all patients using a percutaneous transseptal antegrade approach and a multitrack balloon technique. The P/P-R segment ratio and echocardiographic variables were measured before and 48-72 h after the procedure. The optimal cutoff point for differences in the Macruz index to determine clinical success was evaluated by receiver operating characteristic analysis by calculating the area under the curve as giving the maximum sum of sensitivity and specificity for the significant test.

RESULTS

In the patient group (mean age 42.9 ± 11.1 years), the preprocedural Macruz index was significantly higher than in the control group (2.79 ± 1.03 vs. 1.29 ± 0.11; p < 0.001). In the successful-procedure group (n = 53), the mean postindex value was significantly lower (2.12 ± 0.71 vs. 2.81 ± 1.0, p = 0.020), and the decrease in the Macruz index was significantly higher than in the unsuccessful-procedure group (p = 0.007). An index decrease of 0.105 was the best cutoff value to distinguish the successful-PMBV group from the unsuccessful- PMBV group (area under the curve = 0.888, 95% confidence interval 0.788-0.988, p < 0.001).

CONCLUSION

The Macruz index was significantly higher in patients with MS compared to healthy subjects. A greater decrease in the Macruz index was associated with a successful PMBV.

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.

Mitral balloon valvuloplasty

Percutaneous mitral balloon valvuloplasty (MBV) was introduced in 1984 by Inoue who developed the procedure as a logical extension of surgical closed commissurotomy. Since then, MBV has emerged as the treatment of choice for severe pliable rheumatic mitral stenosis (MS). With increasing experience and better selection of patient, the immediate results of the procedure have improved and the rate of complications declined. When the reported complications of MBV are viewed in aggregate, complications occur at approximately the following rates: mortality (0-0.5%), cerebral accident (1-2%), mitral regurgitation (MR) requiring surgery (1.6-3%). These complication rates compare favorably to those reported after surgical commissurotomy. Several randomized trials reported similar hemodynamic results with MBV and surgical commissurotomy. Restenosis after MBV ranges from 4% to 70% depending on the patient selection, valve morphology, and duration of follow-up. Restenosis was encountered in 31% of the author's series at mean follow-up 9 ± 5.2 years (range 1.5-19 years) and the 10, 15, and 19 years restenosis-free survival rates were (78 ± 2%) (52 ± 3%) and (26 ± 4%), respectively, and were significantly higher for patients with favorable mitral morphology (MES ⩽ 8) at 88 ± 2%, 67 ± 4% and 40 ± 6%), respectively (P < 0.0001). The 10, 15, and 19 years event-free survival rates were (88 ± 2%, 60 ± 4% and 28 ± 7%, respectively, and were significantly higher for patients with favorable mitral morphology (92 ± 2%, 70 ± 4% and 42 ± 7%, respectively (P < 0.0001). The effect of MBV on severe pulmonary hypertension, concomitant severe tricuspid regurgitation, left ventricular function, left atrial size, and atrial fibrillation are addressed in this review. In addition, the application of MBV in specific clinical situations such as in children, during pregnancy and for restenosis is discussed.

Percutaneous mitral balloon valvotomy

Percutaneous mitral balloon valvotomy (PMBV) was introduced in 1984 by Inoue who developed the procedure as a logical extension of surgical closed commissurotomy. Since then, PMBV has emerged as the treatment of choice for severe pliable rheumatic mitral stenosis (MS). With increasing experience and better selection of patient, the immediate results of the procedure have improved and the rate of complications declined. When the reported complications of PMBV are viewed in aggregate, complications occur at approximately the following rates: mortality (0-0.5%), cerebral accident (0.5-1%), mitral regurgitation (MR) requiring surgery (1.6-3%). These complication rates compare favorably to those reported after surgical commissurotomy. Several randomized trials reported similar hemodynamic results with PMBV and surgical commissurotomy. Restenosis after PMBV ranges from 4 to 70% depending on the patient selection, valve morphology, and duration of follow up. Restenosis was encountered in 21% of the author's series at mean follow-up 6 +/- 4.5 years and the 10 and 15 years restenosis-free survival rates were (70 +/- 3)% and (44 +/- 5)%, respectively, and were significantly higher for patients with favorable mitral morphology (85 +/- 3% and 65 +/- 6%), respectively (P < 0.0001). The 10 and 15 years event-free survival rates were (79 +/- 2)% and (43 +/- 9)% and were significantly higher for patients with favorable mitral morphology (88 +/- 2)% and (66 +/- 6)%, respectively (P < 0.0001). The effect of PMBV on severe pulmonary hypertension, concomitant severe tricuspid regurgitation, left ventricular function, left atrial size, and atrial fibrillation are addressed in this review. In addition, the application of PMBV in specific clinical situations such as in children, during pregnancy and for restenosis is discussed.