Influence of mitral valve morphology on double-balloon catheter balloon valvuloplasty in patients with mitral stenosis. Analysis of factors predicting immediate and 3-month results

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.

Impact of 3D transesophageal echocardiography assessment of mitral valve on short-term outcome of Balloon Mitral Valvuloplasty using additional quantitative parameters

The goals of this prospective observational study were to identify quantitative morphological factors that might aid in the prediction of PBMV outcome, as well as to define the function of 3D TEE in mitral valve evaluation. Material and Methods: The trial comprised seventy individuals who had isolated severe rheumatic Mitral Stenosis (MS) who were scheduled for PBMV between October 2017 and March 2021. Trans-thoracic echocardiography (TTE) was used for pre-procedural evaluation. Posterior to Anterior Leaflet Length Ratio (P/ALLR), Commissural Area Ratio (CAR), Doming Height (DH), and Calcification Score (Ca score) were also assessed using 2D and 3D-Trans-esophageal Echocardiography (TEE). Following that, all patients were monitored for three months. Results: We have had 50(71.5%) successful procedures and 20(28.5%) unsuccessful procedures. The additional parameters showed highly significant difference between successful and un-successful groups (P-value <0.001). The cut-off points that predict successful procedures were; P/A LLR >0.6 and >0.55 by 2-D and 3-D TEE respectively, CAR ≤ 1.28 and ≤ 1.25 by 2-D and 3-D TEE respectively, DH > 1.2 cm by 2-D TEE, and Ca Score ≤ 2. Conclusion: In our research, we discovered that these characteristics may predict the result of PBMV and contribute value to the semi-quantitative methodologies we adopted to use.

Rheumatic Mitral Valve Stenosis: Diagnosis and Treatment Options

PURPOSE OF REVIEW

This review provides an update on rheumatic mitral stenosis. Acute rheumatic fever (RF), the sequela of group A β-hemolytic streptococcal infection, is the major etiology for mitral stenosis (MS).

RECENT FINDINGS

While the incidence of acute RF in the Western world had substantially declined over the past five decades, this trend is reversing due to immigration from non-industrialized countries where rheumatic heart disease (RHD) is higher. Pre-procedural evaluation for treatment of MS using a multimodality approach with 2D and 3D transthoracic and transesophageal echo, stress echo, cardiac CT scanning, and cardiac MRI as well as hemodynamic assessment by cardiac catheterization is discussed. The current methods of percutaneous mitral balloon commissurotomy (PMBC) and surgery are also discussed. New data on long-term follow-up after PMBC is also presented. For severe rheumatic MS, medical therapy is ineffective and definitive therapy entails PMBC in patients with suitable morphological mitral valve (MV) characteristics, or surgery. As procedural outcomes depend heavily on appropriate case selection, definitive imaging and interpretation are crucial. It is also important to understand the indications as well as morphological MV characteristics to identify the appropriate treatment with PMBC or surgery.

Stepwise Protocols for Scoring of Mitral Valve using Three-Dimensional Transthoracic Echocardiography in Mitral Stenosis

Aim:

This study aims to propose protocols that enable scoring of mitral valve (MV) in mitral stenosis using the three-dimensional (3D) scoring system.

Methods:

A two-staged study was conducted. The first stage was designed to select the best 3D images of MV leaflets and chordae through analysis of 471 images. The second stage was designed to organize the best 3D images into protocols for complete scoring of MV. It included 35 consecutive patients; 23 had sinus rhythm (SR) and 12 had atrial fibrillation (AF). Both single- and multi-beat 3D acquisition from apical and parasternal windows were focused on MV leaflets and chordae using all 3D modalities (live, zoom, and full volume). To propose the protocols, 1563 images were analyzed.

Results:

In SR with good apical window, 2 protocols were recommended for complete scoring of leaflets and chordae (4 zoom 3D images [1 image for leaflets and 3 images for chordae] and 1 full-volume 3D image) using single- and multi-beat acquisition. In AF, the same 2 protocols using single-beat acquisition were recommended. From parasternal window, complete scoring of leaflets was obtained by 3 recommended protocols (single- or multi-beat zoom 3D images from parasternal short axis [PSAX], multibeat live 3D images from PSAX, and single- or multi-beat full-volume 3D images from parasternal long axis) in SR and 1 protocol in AF (single-beat zoom 3D images from PSAX). Scoring of chordae was incomplete in all patients by all 3D modalities.

Conclusions:

The proposed 3D-transthoracic echocardiography protocols suit all patients regardless of echo window and heart rhythm and enabled complete MV scoring.

The role of echocardiography during mitral valve percutaneous interventions

Transesophageal echocardiography is routinely used to guide percutaneous interventions involving the mitral valve. Mitral balloon valvuloplasty for rheumatic mitral valve stenosis (MS) was the first percutaneous intervention to gain wide acceptance. New techniques have been developed to treat degenerative and functional mitral regurgitation (MR) as well as paravalvular mitral leak (PVML). This review describes the use of echocardiography for transcatheter treatment of MS, MR, and PVML.

New Scores for the Assessment of Mitral Stenosis Using Real-Time Three-Dimensional Echocardiography

Nonsurgical management of patients with symptomatic mitral valve stenosis has been established as the therapeutic modality of choice for two decades. Catheter-based balloon dilation of the stenotic valvular area has been shown, at least, as effective as surgical interventions. Unfavorable results of catheter-based interventions are largely due to unfavorable morphology of the valve apparatus, particularly leaflets calcification and subvalvular apparatus involvement. A mitral valve score has been proposed in Boston, MA, about two decades ago, based on morphologic assessment of mitral valve apparatus by two-dimensional (2D) echocardiography to predict successful balloon dilation of the mitral valve. Several other scores have been developed in the following years in order to more successfully predict balloon dilatation outcome. However, all those scores were based on 2D echocardiography, which is limited by ability to distinguish calcification and subvalvular involvement. The introduction of new matrix-based ultrasound probe has allowed 3D echocardiography (3DE) to provide more detailed morphologic analysis of mitral valve apparatus including calcification and subvalvular involvement. Recently, a new 3DE scoring system has been proposed by our group, which represents an important leap into refinement of the use of echocardiography guiding mitral valve interventions.

Validation of a new score for the assessment of mitral stenosis using real-time three-dimensional echocardiography

BACKGROUND

The aim of this study was to validate a new real-time three-dimensional echocardiography (RT3DE) score for evaluating patients with mitral stenosis (MS).

METHODS

A two-staged study was conducted. In the first stage, the feasibility of a new RT3DE score was assessed in 17 patients with MS. The second stage was planned to validate the RT3DE score in 74 consecutive patients undergoing percutaneous mitral valvuloplasty. The new RT3DE score was constructed by dividing each mitral valve (MV) leaflet into 3 scallops and was composed of 31 points (indicating increasing abnormality), including 6 points for thickness, 6 for mobility, 10 for calcification, and 9 for subvalvular apparatus involvement. The total RT3DE score was calculated and defined as mild (<8), moderate (8-13), or severe (>or=14). MV morphology was assessed using Wilkins's score and compared with the new RT3DE score.

RESULTS

In the first stage, the RT3DE score was feasible and easily applied to all patients, with good interobserver and intraobserver agreement. In the second stage, RT3DE improved MV morphologic assessment, particularly for the detection of calcification and commissural splitting. Both scores were correlated for assessment of thickness and calcification (r = 0.63, P < .0001, and r = 0.44, P < .0001, respectively). Predictors of optimal percutaneous mitral valvuloplasty success by Wilkins's score were leaflet calcification and subvalvular apparatus involvement, and those by RT3DE score were leaflet mobility and subvalvular apparatus involvement. The incidence and severity of mitral regurgitation were associated with high-calcification RT3DE score.

CONCLUSION

The new RT3DE score is feasible and highly reproducible for the assessment of MV morphology in patients with MS. It can provide incremental prognostic information in addition to Wilkins's score.

Echocardiography-guided interventions

A major advantage of echocardiography over other advanced imaging modalities (magnetic resonance imaging, computed tomographic angiography) is that echocardiography is mobile and real time. Echocardiograms can be recorded at the bedside, in the cardiac catheterization laboratory, in the cardiovascular intensive care unit, in the emergency room-indeed, any place that can accommodate a wheeled cart. This tremendous advantage allows for the performance of imaging immediately before, during, and after various procedures involving interventions. The purpose of this report is to review the use of echocardiography to guide interventions. We provide information on the selection of patients for interventions, monitoring during the performance of interventions, and assessing the effects of interventions after their completion. In this document, we address the use of echocardiography in commonly performed procedures: transatrial septal catheterization, pericardiocentesis, myocardial biopsy, percutaneous transvenous balloon valvuloplasty, catheter closure of atrial septal defects (ASDs) and patent foramen ovale (PFO), alcohol septal ablation for hypertrophic cardiomyopathy, and cardiac electrophysiology. A concluding section addresses interventions that are presently investigational but are likely to enter the realm of practice in the very near future: complex mitral valve repairs, left atrial appendage (LAA) occlusion devices, 3-dimensional (3D) echocardiographic guidance, and percutaneous aortic valve replacement. The use of echocardiography to select and guide cardiac resynchronization therapy has recently been addressed in a separate document published by the American Society of Echocardiography and is not further discussed in this document. The use of imaging techniques to guide even well-established procedures enhances the efficiency and safety of these procedures.

Percutaneous mitral balloon valvuloplasty

Almost all mitral stenosis (MS) is rheumatic in etiology. The patient with MS who is symptomatic despite medical therapy should undergo percutaneous mitral balloon valvuloplasty or mitral valvular surgery (commissurotomy or replacement). The choice of procedure is determined by patient preference and the echocardiographic morphologic features of the valvular and subvalvular apparati. With balloon valvuloplasty, the rate of success is > 90%. At institutions where operators are experienced with balloon valvuloplasty and open surgical commissurotomy, their acute and long-term results are comparable. Balloon valvuloplasty occasionally is associated with complications, including death in 0 to 1%, moderate or severe valvular regurgitation in 3 to 5%, and systemic embolization in 1 to 3%.

Echocardiographic assessment of mitral valve morphology after Percutaneous Transvenous Mitral Commissurotomy (PTMC)

AIMS

PTMC produces significant changes in mitral valve morphology as improvement in leaflets mobility. The determinants of such improvement have not been assessed before.

METHODS AND RESULTS

The study included 291 symptomatic patients with mitral stenosis undergoing PTMC. Post-PTMC subvalvular splitting area was a determinant of post-PTMC excursion in both the anterior (B 0.16, 95% CI 0.03 to 0.30, p < 0.05) and the posterior (B 0.12, 95% CI 0.01 to 0.24, p < 0.05) leaflets. Another determinant was the post-PTMC transmitral pressure gradient for anterior (B -0.02, 95% CI -0.04 to -0.005, p < 0.01) and posterior (B -0.01, 95% CI -0.04 to -0.005, p < 0.05) leaflets excursion. The relationship between post-PTMC MVA and leaflet excursion was non-linear "S curve". There was a steep increase of both anterior (p, 0.02) and posterior (p, 0.03) leaflets excursion with increased MVA till the MVA reached a value of about 1.5 cm2; after which both linear and S curves became nearly parallel.

CONCLUSION

The improvement in leaflets excursion after PTMC is determined by several morphologic and hemodynamic changes produced in the valve. The increase in MVA improves mobility within limit; after which any further increase in MVA is not associated by a significant improvement in mobility in both leaflets.

The Subvalvular Apparatus in Rheumatic Mitral Stenosis *

The assessment of the structure and function of the subvalvular apparatus (SVA) in patients with rheumatic mitral stenosis (MS) is complex, yet is of major importance prior to therapeutic decision making. Currently available methods of assessment are neither sufficiently accurate nor feasible. We review anatomic and functional aspects of the SVA and define SVA involvement in rheumatic MS. The role of various noninvasive and invasive methods for evaluating the integrity and function of SVA in rheumatic MS, as well as clinical implications and pitfalls in assessment of SVA are also discussed.

Echocardiographic Criteria in Selection of Patients for Percutaneous Mitral Commissurotomy

The purpose of this report is to review the role of echocardiography in the selection of patients for percutaneous mitral commissurotomy (PMC). Echocardiography has become the standard for the assessment of the severity of mitral stenosis and of its consequences. PMC is usually performed only in patients with a valve area of < 1.5 cm(2), whereas pulmonary hypertension or spontaneous echo contrast in the left atrium may lead to intervention in patients with few symptoms. The next step of the echocardiographic evaluation is to eliminate contraindications: left atrial thrombosis (by the systematic performance of a transesophageal examination before PMC), mitral regurgitation >/= 2/4, severe aortic valve disease, mixed tricuspid valve disease, and massive or bicommissural calcification. Finally, echocardiography allows the classification of patients into different anatomic groups for prognostic consideration. There is controversy regarding the best echo score system in the prediction of the results of PMC. Scores using a global evaluation of the valve anatomy are the most widely used, whereas more recently, scores taking into account the uneven distribution of the disease have had promising preliminary results. Overall, echo scores are useful criteria for selecting candidates for PMC, but they should be considered together with the other clinical and procedural variables. Thus, echocardiography has an important role in the selection of patients for PMC, as well as for the guidance of the procedure, the evaluation of the results, and surveillance.

Percutaneous balloon mitral valvuloplasty using the Inoue balloon: analysis of echocardiographic and other variables related to immediate outcome

To determine whether the mitral valve morphology influences the results of percutaneous balloon mitral valvuloplasty for mitral stenosis, two-dimensional echocardiography was performed before valvuloplasty in 126 patients (mean age 25.5+/-9.4 years) and in 30 normal controls. The 2D echocardiographic features of mitral valve leaflets: thickness, length and motion; diastolic mitral valvular excursion; chordal length; mitral annular diameter; subvalvular distance ratio; distance between mid mitral annulus to left ventricular apex, base and tip of papillary muscle and effective balloon dilating area, effective balloon dilating area/body surface area and effective balloon dilating diameter/mitral annular diameter were then correlated to the immediate post-valvuloplasty mitral valve area. For the total patients population, post-valvuloplasty valve area increased from 0.67+/-0.17 to 2.1+/-0.86 cm2 (P<0.0001), mean transmitral diastolic gradient decreased from 24.5+/-9.0 to 6.0+/-3.0 mm Hg (P<0.0001), mean left atrial pressure decreased from 29.7+/-6.2 to 12.7+/-4.8 mm Hg (P<0.0001), mean pulmonary artery pressure decreased from 44.8+/-14.2 to 25.4+/-9.5 mm Hg (P<0.0001) and cardiac index increased from 2.7+/-0.38 to 3.1+/-0.55 l/min/m2 (P<0.0001). The patients were divided into three groups on the basis of post-valvuloplasty mitral valve area. Group I had valve area <1.5 cm2, group II had valve area from 1.5 to 1.9 cm2 and group III had valve area > or =2.0 cm2. On comparison, no statistically significant difference was found in any of the echocardiographic variables in the three groups. On univariate, multivariate, multiple regression and discriminate function analysis, none of the variables were found to have significant influence on immediate result of valvuloplasty. There was no significant difference in the incidence of mitral regurgitation in any of the three groups. We conclude that the extent of mitral valvular and subvalvular deformity do not have a significant effect on the immediate outcome of mitral valvuloplasty using the Inoue balloon and it can be successfully performed in patients with severe subvalvular fibrosis. Unique balloon geometry and stepwise balloon sizing may explain these acceptable immediate results in severely deformed valves.

Influence of sub valvular pathology on immediate results and follow up events of Inoue balloon mitral valvotomy

We evaluated the influence of sub valvular pathology (SVP) on the immediate results and follow up events of Inoue Balloon Mitral Valvotomy (IBMY) in 206 patients with severe SVP (Group I) and compared their outcome with 206 age and sex matched patients selected from the rest of 619 patients having mild/moderate SVP (Group II). Pre-procedure echocardiographic recordings were reviewed and mitral valve morphology was evaluated using U.S. California Score. The severe SVP group had lower mitral valve areas (MVA) (0.7 cm2 vs. 0.8 cm2) and higher mean pulmonary artery pressure (MPAP) (46.3+/-16.9 mmHg vs. 40.7+/-16.25 mmHg) and mean pulmonary capillary wedge pressure (PCWP) (27.5+/-7.3 mmHg vs. 25.7+/-8.0 mmHg) (p<0.001). IBMV was done using standard technique. The procedure was technically successful in 192/206 patients (93.2%) in group I and 187/206 (91%) in group II (p=ns). The mean transmitral gradient decreased from 24.8+/-7.6 mmHg to 7.46+/-3.4 mmHg while mean PCWP fell from 27.5+/-7.3 mmHg to 12.2+/-5.6 mmHg and MPAP fell from 46.3+/-16.9 mmHg to 23.6+/-12.2 mmHg (p=<0.001). MVA increased from 0.7+/-0.2 cm2 to 1.7+/-0.4 cm2 (p=<0.001). Severe mitral regurgitation (MR) occurred in 2 patients out of which one patient, who had associated coronary artery disease, died post operatively, and moderate MR occurred in 8 patients. The results achieved in patients with severe SVP were not statistically different from those with mild/moderate SVP. The benefits achieved immediate post IBMV were sustained in 184 patients with severe SVP who were available for follow up at a mean duration of 15.2 months (range 3 months to 51 months). Thus IBMV is safe and effective in patients with severe SVP. This group of patients with severe SVP are more hemodynamically deranged pre-BMV and also achieve better hemodynamic benefit compared to those with mild/moderate SVP. Severe SVP does not have any adverse effect either on immediate results (success/occurrence of MR) or on intermediate term follow up.

Assessment of valvular heart disease. Why echocardiography is an essential component

Assessment of patients with valvular heart disease has undergone many changes in the past few decades with the introduction of noninvasive techniques such as echocardiography. Along with the history, physical examination, electrocardiogram, and chest films, echocardiography is an important component of the assessment, providing essential information for diagnosis and follow-up.

Retrograde nontransseptal balloon mitral valvuloplasty: immediate results and intermediate long-term outcome in 441 cases--a multicenter experience

OBJECTIVES

Our aim was to present the immediate and intermediate long-term results of the application of retrograde nontransseptal balloon mitral valvuloplasty (RNBMV) in four cooperating centers from Greece and India.

BACKGROUND

RNBMV is a purely transarterial method of balloon valvuloplasty, developed with the aim to avoid complications associated with transseptal catheterization. Only single-center experience with RNBMV has been previously reported.

METHODS

The procedure was attempted in 441 patients with symptomatic mitral stenosis (320 women, 121 men, mean age [+/-SD] 44+/-11 years, mean echocardiographic score [+/-SD] 7.7+/-2.0) from 1988 to 1996. Three hundred eighty-five patients with successful immediate outcome were followed clinically for a mean [+/-SD] of 3.5+/-1.9 (range, 0.5-9.1) years.

RESULTS

A technically successful procedure was achieved in 388 (88%) cases. The echocardiographic score (p < 0.001), male gender (p=0.005), preprocedural mitral regurgitation (p=0.007) and previous surgical commissurotomy (p=0.029) were unfavorable predictors of immediate outcome. Complications included death (0.2%), severe mitral regurgitation (3.4%) and injury of the femoral artery (1.1%). Event-free (freedom from cardiac death, mitral valve surgery, repeat valvuloplasty and NYHA class > II symptoms) survival rates (+/-SEM) were 100%, 96.9+/-0.9%, 89.8+/-1.9% and 75.5+/-5.5% at 1, 2, 4 and 9 years, respectively. The echocardiographic score (p < 0.001), NYHA class (p=0.008) and postprocedural mitral valve area (p=0.009) were significant independent predictors of intermediate long-term outcome.

CONCLUSIONS

Multicenter experience indicates that RNBMV is a safe and effective technique for the treatment of symptomatic mitral stenosis. As with the transseptal approach, patients with favorable mitral valve anatomy derive the greatest immediate and intermediate long-term benefit from this procedure.

Predictors of event-free survival after percutaneous mitral commissurotomy

OBJECTIVE

To assess the long term functional result after percutaneous mitral commissurotomy and identify the predictors of event-free survival following 10 years of experience.

DESIGN

Analysis of clinical, echocardiographic, and haemodynamic variables at baseline and after the procedure by univariate and multivariate analyses (Cox model).

SETTING

University hospital.

PATIENTS

532 consecutive patients receiving percutaneous mitral commissurotomy in the same institution.

RESULTS

The mean (SD) follow up was 3.8 (4.0) years. Survival at 3, 5, and 7.5 years was 94%, 91%, and 83%, respectively; event-free survival was 84%, 74%, and 52%. Mitral valve anatomy was identified as the strongest independent predictor of event-free survival. Age, cardiothoracic ratio, mean pulmonary artery pressure, and mean echocardiographic mitral gradient after commissurotomy were also found to be independent predictors of long term functional results. Event-free survival was 92%, 84%, and 70% at 3, 5, and 7.5 years in patients with favourable anatomy (echo score = 1), 86%, 73%, and 34% in patients with intermediate anatomy (echo score = 2), and 45%, 25%, and 16% in patients with unfavourable anatomy (echo score = 3). In patients aged < or = 65 years, the event-free survival rate was 80%, 70%, and 45% at 3, 5, and 7.5 years v 52%, 38%, and 17% in patients aged > 65 years.

CONCLUSIONS

The anatomical form of the mitral valve and the patient's age were the most powerful predictors of event-free survival. Patients with intermediate or unfavourable anatomy and those aged > 65 years have low 5 and 7.5 year event-free survival rates. This must be taken into account when discussing the indications for percutaneous mitral commissurotomy; immediate mitral valve replacement is a reasonable alternative to balloon mitral commissurotomy in patients with higher risk of functional deterioration after the procedure.

Echocardiography in Percutaneous Balloon Mitral Valvuloplasty

Percutaneous balloon valvuloplasty (BV) has been used successfully in recent years for the relief of mitral stenosis, and in many instances, as an alternative to cardiac surgery. This procedure requires precise evaluation of both valve morphology and function for preprocedure decision making and follow-up of patients. Two-dimensional (2-D) echocardiography is a unique, noninvasive tool for evaluating morphologic characteristics of valve, subvalvular apparatus, and valve annular size. Doppler echocardiography provides functional information on transvalvular flow velocity, which can be used to derive pressure gradient across valve and regurgitant flow. Mitral valve area can be either obtained from 2-D echocardiography or derived from Doppler pressure half time. Echocardiography is currently the most widely used technique for assessing results of percutaneous BV. More recently, transesophageal echocardiography (TEE) has been used for the evaluation of patients undergoing percutaneous mitral BV in whom left atrial thrombus is suspected and for the intraoperative monitoring of the valvuloplasty procedure. In this article we discuss the advantages and limitations of both transthoracic echocardiography and TEE, its recent developments in monitoring the procedure, evaluation of immediate results and long term follow-up after the valvuloplasty procedure, and its clinical utility in the selection of patients for percutaneous BV.

Percutaneous balloon mitral valvuloplasty

Percutaneous balloon mitral valvuloplasty, first performed by Inoue in 1982, was a rational progression from 4 decades of experience with the blunt surgical dilatation technique of closed mitral commissurotomy. As with surgical commissurotomy, balloon valvuloplasty relieves mitral stenosis by the splitting of fused commissures. A series of studies have shown that balloon valvuloplasty achieves excellent acute hemodynamic results in close to 90% of patients, with a typical 100% increase in mitral valve area. Over the past 15 years since Inoue's first patient, a number of other techniques have been introduced and largely discarded in favor of the original approach. Advances have occurred along the lines of improved noninvasive assessment of mitral valve disease, which have allowed better case selection and prediction of outcome. Follow-up series have shown sustained improvement, with modest rates of complications and restenosis. Comparative studies have shown that balloon valvuloplasty is as effective and safe as surgical commissurotomy, and is a cost-effective procedure of first choice in ideal patients.

Predictors of long-term event-free survival after percutaneous balloon mitral valvuloplasty

Previous studies have shown that long-term event-free survival after percutaneous balloon mitral valvuloplasty (PBMV) could be predicted by several baseline characteristics. However, the extent of the predictive variables has not been defined accurately yet. In this study, 40 baseline demographic, clinical, echocardiographic, and hemodynamic variables of 128 consecutive patients with mitral stenosis who underwent PBMV in a single institution, were analyzed in order to predict long-term event-free survival, defined as absence of death, mitral valve replacement, or repeat PBMV. Univariate survival analysis showed that age (p = 0.03), history of commissurotomy or mitral valvuloplasty (p = 0.05), calcium grade (p = 0.008), echo score (p = 0.0001), preprocedure cardiac output (p = 0.03), preprocedure valve area (p = 0.0007), postprocedure mean left atrial pressure (p = 0.0001), postprocedure valve area (p = 0.0001), postprocedure valve gradient (p = 0.013), and postprocedural mitral regurgitation (p = 0.01) were statistically significant predictors of event-free survival. Additionally, the absolute and/or relative procedural change of the following variables were found to be statistically significant predictors of event-free survival: left atrial pressure (p = 0.01), valve area (p = 0.0001), and valve gradient (p = 0.02). Multivariate Cox proportional hazard analysis indicated that when only variables available before the procedure were considered, echo score (p = 0.002) and preprocedure valve area (p = 0.0002) were found to be independent predictors of event-free survival. When both pre- and postprocedure variables were considered, echo score (p = 0.002) and postprocedure valve area (p = 0.0001) were found to be independent predictors of event-free survival. In conclusion, mitral valve morphology reflected by echo score, and baseline and postprocedure mitral valve area were found to be the strongest independent predictors of event-free survival after PBMV.

Mitral valve replacement after percutaneous transvenous mitral commissurotomy

Percutaneous transvenous mitral commissurotomy is widely performed as the first choice of the non-pharmacological treatments for mitral stenosis. Five patients have been identified who required mitral valve replacement after percutaneous transvenous mitral commissurotomy. The causes leading to mitral valve replacement were mitral regurgitation in three cases and insufficient commissurotomy in two. Massive mitral regurgitation is one of the most serious complications of percutaneous transvenous mitral commissurotomy. This report aims to elucidate the mechanism of massive mitral regurgitation occurring during percutaneous transvenous mitral commissurotomy. In every such case, there was a large tear in the posterior leaflet without any split in the commissures. The Japanese literature reports that 16 patients have undergone mitral valve replacement for massive regurgitation after percutaneous transvenous mitral commissurotomy: 14 of these cases had a tear in one of the leaflets and no evidence of splitting of the posterior commissure. These facts indicate that relative fragility of the leaflets as compared with rigidity of commissural fusion, especially in the posterior commissure, is an important factor of massive mitral regurgitation during percutaneous transvenous mitral commissurotomy.

Advantage of Inoue balloon catheter in mitral balloon valvotomy: experience with 220 consecutive patients

Percutaneous mitral balloon valvotomy (PMV) using the Inoue balloon catheter was attempted in 220 consecutive patients with severe symptomatic mitral stenosis. Their age range was 10-63 mean 30 +/- 10 years; 161 patients were females and 59 were males; 29 patients were in atrial fibrillation. Eleven patients were pregnant; 14 patients underwent previous surgical commissurotomy. The procedure was technically successfully performed in 215 (97.7%) patients. The mean fluoroscopy time was 15.5 +/- 6.4 min and mean procedure time was 109 +/- 79 min. Optimal results (group I) was achieved in 207 patients who have mitral score of 7 +/- 1. PMV resulted in decrease in left atrial pressure from 23 +/- 5 to 14 +/- 4 mm Hg (P < 0.001), the mean mitral valve gradient (MVG) decreased from 15 +/- 4 to 6 +/- 3 mm Hg (P < 0.001). The mitral valve area (MVA) by catheter increased from 0.7 +/- 0.2 to 1.7 +/- 0.5 cm2 (P < 0.001) and MVA as determined by echocardiography (2DE) increased from 0.8 +/- 0.1 to 1.9 +/- 0.3 cm2 (P < 0.001). The results were suboptimal in eight patients who have a mitral score of 10 +/- 1 (group II) MVA by catheter increased from 0.7 +/- 0.2 to 1 +/- 0.1 cm2 and Doppler MVA increased from 0.8 +/- 0.1 to 1.3 +/- 0.1 cm2. There were no deaths or thromboembolism. Two patients developed cardiac tamponade; mild mitral regurgitation (MR) developed in 24 patients (11%) and increased by one grade in another 22 patients (10%). Severe MR was encountered in three patients (1.4%). A small ASD (QP/QS < or = 1.3) was detected by oximetry in 5% of patients and by color-flow mapping in 26% of patients. One hundred fifty-eight patients from group I were followed up, for a mean of 32 +/- 12 months; MVA remained at 1.7 +/- 0.4 cm2. Seven patients developed mitral restenosis in group I, and 5 out of 8 patients developed restenosis in group II. We conclude that the hemodynamic results are good and comparable with those reported with double balloon technique. However, the Inoue balloon has several advantages over the double balloon technique: (1) low incidence of mitral regurgitation and ASDs; (2) shorter procedure and fluoroscopy time; and (3) low complication rates and the valve anatomy affects the immediate and late outcome of mitral balloon valvotomy.

Inoue balloon mitral valvotomy in patients with severe valvular and subvalvular deformity

OBJECTIVES

This study evaluated the immediate and long-term results of percutaneous Inoue balloon mitral valvotomy in patients with severe valvular and subvalvular deformity.

METHODS

We reviewed the prevalvotomy transthoracic echocardiograms of patients from the North American multicenter Inoue registry with total Massachusetts General Hospital (MGH) echocardiographic scores > or = 10. The echocardiograms were rescored by two investigators to assess valvular and subvalvular morphology to eliminate interinstitutional variability. Ninety patients were originally assigned scores > or = 10. After rescoring, 18 patients (20%) were eliminated, leaving 72 study patients.

RESULTS

Balloon mitral valvotomy was technically successful in 69 (96%) of the 72 patients. Mean (+/- SD) mitral valve area increased from 0.9 +/- 0.3 to 1.5 +/- 0.5 cm2. An immediate optimal result, defined as > or = 50% increase in mitral valve area or a final area > or = 1.5 cm2 with no major complications, was achieved in 46 patients (64%). End points for clinical follow-up (events) included mitral valve replacement, repeat valvotomy or death. At a mean follow-up of 22.9 +/- 11.0 months, 22 patients (31%) required mitral valve replacement or a second valvotomy, 9 patients (13%) died, and 32 patients (45%) were in New York Heart Association functional class I or II. Univariate predictors of an immediate optimal result included sinus rhythm, male gender and a lower University of Southern California commissural calcium score. Only sinus rhythm predicted an optimal result by multivariate analysis. Actuarial 3-year event-free survival was 42%. Univariate predictors of event-free survival were a lower grade of mitral regurgitation, lower MGH total echocardiographic score, lower MGH leaflet thickness subscore and lower prevalvotomy left ventricular systolic pressure. Only grade of mitral regurgitation after valvotomy predicted event-free survival by multivariate analysis.

CONCLUSIONS

Inoue mitral valvotomy in patients with severe valvular and subvalvular deformity has a high technical success rate and good immediate hemodynamic result but a high cardiovascular event rate in follow-up. Mitral valve replacement should be considered in surgical candidates with an MGH total echocardiographic score > or = 10 because it may be able to provide better long-term event-free survival. Balloon valvotomy remains a reasonable palliative therapeutic option for some patients with severe valvular deformity and high surgical risk.

Pathology of mitral valve stenosis and pure mitral regurgitation--Part I

This two-part article examines the histologic and morphologic basis for stenotic and purely regurgitant mitral valves. In Part I, conditions producing mitral valve stenosis are reviewed. In over 99% of stenotic mitral valves, the etiology is rheumatic disease. Other rare causes of mitral stenosis include congenital malformed valves, active infective endocarditis, massive annular calcium, and metabolic or enzymatic abnormalities. In Part II, conditions producing pure mitral regurgitation will be discussed. In contrast to the few causes of mitral stenosis, the causes of pure (no element of stenosis) mitral regurgitation are multiple. Some of the conditions producing pure regurgitation include floppy mitral valves, infective endocarditis, papillary muscle dysfunction, rheumatic disease, and ruptured chordae tendinae.

Influence of intraballoon pressure on development of severe mitral regurgitation after percutaneous transvenous mitral commissurotomy

To evaluate the influence of intra-balloon pressure on the development of severe mitral regurgitation (> or = grade 3+), we measured intraballoon pressure during percutaneous transvenous mitral commissurotomy (PTMC) in 62 patients using the Inoue balloon catheter. The peak intraballoon pressure was 2.29 +/- 0.55 kg/cm2. Severe mitral regurgitation as a result of leaflet tear occurred in 7 patients (11%). Patients were divided into two groups those with (n = 7) and those without (n = 55) severe mitral regurgitation. Intraballoon pressure had been significantly higher in those with vs. those without severe mitral regurgitation (2.76 +/- 0.31 kg/cm2 vs. 2.23 +/- 0.55 kg/cm2, P < 0.01). Multiple logistic regression analysis revealed that the occurrence of severe mitral regurgitation was related to only the peak intraballoon pressure. These data suggest that a high intraballoon pressure is a risk factor for severe mitral regurgitation as a result of leaflet tear.

Percutaneous balloon mitral valvuloplasty: analysis of echocardiographic and other variables related to outcome

To determine whether mitral valve (MV) morphology influences the result of balloon mitral valvuloplasty (BMV) for mitral stenosis, two-dimensional echocardiography was performed before BMV in 53 patients and in 25 normal controls. The two-dimensional echocardiographic features of MV leaflets: thickness, length and motion, diastolic MV excursion, chordal length, MV annular diameter (MVAnD), subvalvular distance ratio (SDR), and effective balloon dilating area (EBDA) and diameter (EBDD) were then correlated to the immediate post-BMV mitral valve area (MVA). For the total patient population, post-BMV MVA increased from 0.76 +/- 0.24 to 1.91 +/- 0.59 cm2 (p < 0.0001) and mean diastolic transmitral gradient decreased from 20.1 +/- 6.15 to 5.8 +/- 3.29 mm (p < 0.0001). The patients were divided into two groups on the basis of post-BMV MVA. Group I had post-BMV MVA < 2.0 cm2 and group II had post-BMV MVA > or = 2.0 cm2. A statistically significant difference was noted in SDR (0.33 +/- 0.057 vs 0.45 +/- 0.042, p < 0.0001); mid-MV anulus to tip of papillary muscle (PM) distance (20.0 +/- 3.8 vs 27.9 +/- 4.54 mm, p < 0.0001); chordal length (4.3 +/- 3.6 vs 9.8 +/- 3.9 mm, p < 0.0001); diastolic MV excursion (15.5 +/- 2.6 vs 18.2 +/- 4.2 mm, p < 0.01); leaflet mobility (p < 0.05); and EBDA (4.4 +/- 0.6 vs 4.9 +/- 0.5 cm2, p < 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)

Percutaneous balloon mitral valvuloplasty: comparison of double and single (Inoue) balloon techniques

To assess relative merits of the double and single (Inoue) balloon techniques of percutaneous balloon mitral valvuloplasty for treating symptomatic mitral stenosis, 33 patients who underwent dilatation with the double balloon were compared retrospectively with 28 who underwent dilatation with the Inoue balloon. There were no baseline differences in mean left atrial pressure, mean mitral gradient, or calculated mitral valve area between the two groups. The procedure was successful in 89% of patients in the double balloon group and in 93% in the Inoue balloon group. Final mitral valve area and absolute increase in mitral valve area were significantly greater in the double balloon group, in which there was a nonsignificant trend toward greater incidence of acute complications. Final left atrial pressure and mitral gradient were not different. Both techniques are useful and safe.

The comparative value of transesophageal and transthoracic echocardiography before and after percutaneous mitral balloon valvotomy: a prospective study

Transthoracic (TTE) and transesophageal echocardiography (TEE) were performed prospectively on 53 consecutive patients (mean age 59 +/- 14 years) immediately before and within 24 hours of mitral balloon valvotomy to compare the relative value of the two techniques. Biplane TEE was used in 38 patients and single-plane imaging was done in 11. All patients underwent left and right cardiac catheterization, left ventriculography, and coronary angiography. While TEE provided excellent images of the mitral valve in all patients, imaging planes were more limited than by TTE. Mitral valve morphology could be assessed satisfactorily by either technique. Echo scores derived from each showed good correlation (r = 0.90, p < 0.001). TEE transgastric longitudinal scanning provided superior detail of the subvalvar apparatus but only in 20 (53%) of 38 patients. Patients with good transgastric views had significantly smaller left atrial volumes than those without (58 +/- 22 vs 106 +/- 41 cm3, p < 0.001). Mitral valve orifice and the commissures were better assessed by TTE. Before valvotomy, mitral regurgitation (MR) graded by TEE and TTE color flow mapping was concordant with angiography in 80% and 81%, respectively. After valvotomy, TTE color flow mapping failed to detect MR in two of the three patients who developed severe MR. Two of these patients were examined by TEE, which demonstrated both the MR jets as well as leaflet tears. Thrombus was diagnosed in the left atrium in eight patients by TEE and in only one patient by TTE. Biplane TEE was required for accurate thrombus localization and for assessing its size and extent. Five patients with thrombus underwent balloon valvotomy without complications. Left-to-right atrial shunting was detected by TEE and TTE in 95% and 48% of patients, respectively. Flow convergence regions, from which quantitative flow information can be derived, were imaged by TEE only. TTE and TEE have complementary roles. However, TEE is essential for excluding thrombus in the left atrium before balloon valvotomy. After the procedure, TEE is recommended for the evaluation of patients with severe mitral regurgitation.

Balloon mitral commissurotomy in patients aged > or = 70 years

Of 280 patients treated by balloon mitral commissurotomy (BMC) between 1987 and 1991, 28 (10%) were > or = 70 years old. Two patients with associated significant aortic stenosis were excluded from the study. Older patients more often were in New York Heart Association class III or IV (84 vs 67%; p < 0.007) and atrial fibrillation (61 vs 36%; p < 0.0001), and had a higher echocardiographic score (9.3 +/- 2 vs 8 +/- 1.6; p < 0.0004) and a lower baseline cardiac index (2.1 +/- 0.6 vs 2.4 +/- 0.6 liters/min/m2; p < 0.03) than younger ones. Baseline mean pulmonary pressure (37 +/- 11 vs 34 +/- 12 mm Hg), transmitral gradient (14 +/- 4 vs 14 +/- 5 mm Hg) and valve area (1.0 +/- 0.4 vs 1.1 +/- 0.3 cm2) were not different between older and younger patients (p = NS). Acute complications during the procedure (including cardiac perforation, embolism, severe mitral regurgitation and surgical atrial shunt), and 30-day mortality after BMC were more frequent in older than younger patients (27 vs 9% [p < 0.01], and 12 vs 0.8% [p < 0.005], respectively). A complete success, defined as a mitral valve area increase > 25% and postmitral valve area > 1.5 cm2 was obtained in 16 of the 22 older patients (72%) with the completed procedure (compared with 81% of younger ones; p = 0.1).(ABSTRACT TRUNCATED AT 250 WORDS)

Predictors of long-term outcome after percutaneous balloon mitral valvuloplasty

BACKGROUND

Percutaneous balloon mitral valvuloplasty is known to produce short-term hemodynamic and symptomatic improvement in many patients with mitral stenosis. Comprehensive assessment of the clinical usefulness of balloon valvuloplasty requires evaluation of patients' long-term outcomes.

METHODS

We performed balloon mitral valvuloplasty in 146 patients between October 1, 1985, and October 1, 1991. Base-line demographic, clinical, echocardiographic, and hemodynamic variables were evaluated in order to identify predictors of long-term event-free survival.

RESULTS

Balloon mitral valvuloplasty was completed successfully in 136 (93 percent) of the patients in whom the procedure was attempted; it resulted in an increase in the mean (+/- SD) mitral-valve area from 1.0 +/- 0.4 to 2.1 +/- 0.9 cm2 and a decrease in the mean transmitral pressure gradient from 14 +/- 5 to 6 +/- 3 mm Hg (P < 0.001 for both comparisons). The estimated overall five-year survival rate was 76 +/- 5 percent, and the estimated five-year event-free survival rate (the percentage of patients without mitral-valve replacement, repeat valvuloplasty, or death from cardiac causes) was 51 +/- 6 percent. According to multivariate Cox proportional-hazards analysis, the independent predictors of longer event-free survival were a lower mitral-valve echocardiographic score (a measure of mitral-valve deformity; range, 0 for a normal valve to 16 for a seriously deformed valve; P < 0.001), lower left ventricular end-diastolic pressure (P = 0.001), and a lower New York Heart Association (NYHA) functional class (P = 0.04). Patients with no risk factors for early restenosis or only one risk factor (echocardiographic score > 8, left ventricular end-diastolic pressure > 10 mm Hg, or NYHA functional class IV) had a predicted five-year event-free survival rate of 60 to 84 percent, whereas patients with two or three risk factors had a predicted five-year event-free survival rate of only 13 to 41 percent.

CONCLUSIONS

Balloon mitral valvuloplasty as a treatment for selected patients with mitral stenosis has good long-term results. The long-term outcome after this procedure can be predicted on the basis of patients' base-line characteristics.

Long-term follow-up of patients undergoing closed transventricular mitral commissurotomy: a useful surrogate for percutaneous balloon mitral valvuloplasty?

OBJECTIVE

The aim of this study was to determine the long-term outcome and multivariate predictors of late events in patients who underwent transventricular mitral commissurotomy at the Mayo Clinic in the early 1960s.

BACKGROUND

Percutaneous balloon mitral valvuloplasty is an important new procedure for which long-term follow-up data are not yet available. However, such data do exist for patients who have undergone transventricular mitral commissurotomy, a similar but older and more invasive procedure.

METHODS

Follow-up data (mean duration 13.9 years) for 207 women and 60 men who underwent transventricular mitral commissurotomy were obtained from medical records, referring physicians, questionnaires and telephone interviews. Survival and survival free of repeat commissurotomy or mitral valve surgery were estimated with the Kaplan-Meier method. Cox proportional hazards model was used to determine predictors of survival and repeat mitral valve surgery.

RESULTS

Postoperatively, 92% of patients had symptomatic improvement, which was sustained for at least 3 to 4 years in 78%. At 10, 15 and 20 years postoperatively, 79%, 67% and 55%, respectively, of patients were alive and 57%, 36% and 24%, respectively, were alive and free of repeat mitral valve surgery. At 10 years, 90% of all patients were free of transient or fixed cerebrovascular events. In multivariate analyses, atrial fibrillation, age and male gender were independently associated with death, whereas mitral valve calcification, cardiomegaly and mitral regurgitation independently predicted repeat mitral valve surgery.

CONCLUSIONS

Long-term results after transventricular mitral commissurotomy are excellent in selected patients with symptomatic mitral stenosis. Because of similarities in patient selection and mechanisms of mitral valve dilation, similar favorable long-term outcomes may be expected after percutaneous balloon mitral valvuloplasty.

Influence of mitral valve morphology on mitral balloon commissurotomy: immediate and six-month results from the NHLBI Balloon Valvuloplasty Registry

Echocardiographic data were analyzed in 555 patients undergoing mitral balloon commissurotomy (MBC). Patients were enrolled in the National Heart, Lung, and Blood Institute Balloon Valvuloplasty Registry from 24 centers. There were 456 women and 99 men with a mean age of 54 years. Before MBC the two-dimensional echocardiographic variables of mitral valve thickness, mobility, calcification, and subvalvular disease were evaluated and assigned scores of 1 to 4. The mitral valve morphology score was related to mitral valve area (MVA) measured after MBC by cardiac catheterization. The leaflet mobility score was related to the immediate post-MBC MVA: 2.2 +/- 0.8 cm2 for grade 1, 1.9 +/- 0.7 cm2 for grade 2, 1.7 +/- 0.7 cm2 for grade 3, and 1.9 +/- 0.9 cm2 for grade 4 (p less than 0.001). Results of the MVA after MBC showed a similar relationship for each echocardiographic variable. The total morphology score (sum of the four variables) showed a weak relationship to MVA immediately after MBC (r = 0.24), which was persistent at 6 months after MBC (r = -0.25). Multiple regression analysis showed that the MVA after MBC is predicted by pre-MBC MVA (p less than 0.001), left atrial size (p = 0.01), balloon diameter (p = 0.02), cardiac output (p = 0.004), and leaflet mobility (p = 0.01). The R2 of the model was 0.31 (p less than 0.001). Total morphology score, leaflet thickness, calcification, and subvalvular disease were not important univariate or multivariate predictors of the results of MBC.(ABSTRACT TRUNCATED AT 250 WORDS)

Factors influencing immediate results, complications, and short-term follow-up status after Inoue balloon mitral valvotomy: a North American multicenter study

Clinical trials with the Inoue mitral valvotomy balloon have recently begun in the United States. We assessed the effects of 17 demographic, echocardiographic, procedural, and hemodynamic variables on the immediate results, complications, and short-term follow-up of 200 patients in 15 centers undergoing valvotomy with this device. The study population had a mean age +/- SD of 53 +/- 15 years, and the total echocardiographic score was 7.2 +/- 2.4. Valvotomy was technically successful in 96.5% of procedures and increased the mean mitral valve area from 1.0 +/- 0.3 to 1.8 +/- 0.7 cm2 (p less than 0.001); 72% had an increase in valve area greater than or equal to 50%, and 67% had a final area greater than or equal to 1.5 cm2. Major procedural complications included cardiac tamponade during transseptal puncture (1.0%), systemic embolism (1.5%), and severe mitral regurgitation (2.4%); there were no procedural deaths and one hospital death. Multivariate analysis identified the absence of prior surgical commissurotomy and younger age as significant predictors of the gain in mitral valve area, but the correlation coefficients were low. Although the absence of subvalvular disease on echocardiograms was a predictor of a final valve area greater than or equal to 1.5 cm2, the total echocardiographic score did not correlate well with the immediate outcome (r = 0.01, p = NS). No variable was identified as predictive of restenosis, which occurred according to echocardiographic criteria in 14 of 66 (21%) patients evaluated 6 months after valvotomy. Good hemodynamic results with valvotomy were achieved in the majority of patients with low complication rates by many investigators with the use of the Inoue balloon device.(ABSTRACT TRUNCATED AT 250 WORDS)

Long-term (9 to 33 months) echocardiographic follow-up after successful percutaneous mitral commissurotomy

Late results after successful percutaneous mitral commissurotomy were assessed by prospective clinical and echocardiographic follow-up. Fifty-seven patients were followed for a mean of 19 +/- 6 months (range 9 to 33) after the procedure. Mitral valve area (measured by Doppler half-time method) increased from 1.0 +/- 0.2 to 2.2 +/- 0.5 cm2 immediately after commissurotomy, and then decreased to 1.9 +/- 0.5 cm2 at follow-up (p less than 0.05), whereas gradient did not change after its immediate postcommissurotomy reduction. Echocardiographic restenosis (mitral valve area less than or equal to 1.5 cm2 with greater than 50% reduction of initial gain) was seen in 12 of 57 patients (21%). Atrial shunting, detected by transthoracic color Doppler in 61% of patients immediately after the procedure (color flow jet through atrial septum), persisted in 30% at follow-up. Restenosis by univariate analysis correlated with age, smaller valve area after the procedure, and higher echocardiographic score. Multivariate analysis identified leaflet mobility and calcifications as the components of a score that was predictive for restenosis. Magnitude of shunt (pulmonary-to-systemic flow ratio greater than 1.5), use of a Bifoil balloon (2 balloons on 1 shaft), and smaller valve area after the procedure were predictors by multivariate analysis of the persistence of atrial shunting. Clinical improvement persisted at long-term follow-up (mean New York Heart Association class 1.6 +/- 0.6 vs 2.6 +/- 0.6 before commissurotomy). Improvement of greater than or equal to 1 functional class was seen in 75% of patients (80% of those without and 58% of those with restenosis); patients with a shunt did not differ from the entire group.(ABSTRACT TRUNCATED AT 250 WORDS)

Transesophageal echocardiography

Transesophageal echocardiography has provided a new acoustic window to the heart, the great vessels, and the mediastinum. It provides anatomical, functional hemodynamic, and blood flow information. High-quality visualization of left atrial appendage, thoracic aorta, atrial septum, and mitral valvular apparatus can be obtained readily. We discuss historical and technical aspects of transesophageal echocardiography, anatomical views, and major clinical indications for this procedure. These indications include intracardiac masses, thoracic aortic dissection, endocarditis, prosthetic and native cardiac valve function assessment, as well as its value in the detection of intracardiac source of systemic emboli. Furthermore, the role of transesophageal echocardiography in the assessment of coronary artery and congenital heart disease and as an intraoperative diagnostic and monitoring technique is discussed.