Increase In Mitral Valve Area Research Articles

Balloon mitral valvotomy in pregnancy: maternal and fetal outcomes

Background: Rheumatic mitral valve stenosis contributes to significant morbidity in pregnancy. Surgical commissurotomy has been performed during pregnancy in patients with severe mitral stenosis for several decades, but the efficacy and safety of percutaneous balloon mitral valvotomy (BMV) in this subset has not been clearly defined. Study Design: In 1996 and 1997, 40 pregnant women aged 24 ± 5 years underwent BMV at 21 ± 11 weeks of pregnancy. Special shielding was used during BMV to limit radiation to the fetus, except in those who were to undergo medical termination of pregnancy subsequently. A detailed echocardiographic evaluation was performed before and after BMV. After the BMV, the 29 patients in whom pregnancy was continued were assessed every 2 weeks for symptoms and fetal growth. Results: The BMV procedure was successful in 39 patients with an increase in mitral valve area from 0.8 ± 0.2 cm 2 to 1.7 ± 0.2 cm 2 (p < 0.001) and marked symptomatic relief. Fluoroscopy time was 7.8 ± 1.9 minutes. Eleven patients whose BMV was performed before 20 weeks of pregnancy, subsequently underwent medical termination of pregnancy uneventfully. Eighteen patients had a normal delivery, three underwent cesarean section for fetal distress, one had a preterm delivery, and there was one stillbirth. Four patients are continuing pregnancy and two are lost to followup. Fullterm delivery data were available in 23 babies, whose birth weights were 2.32 ± 0.5 kg. None of these babies needed any special care and were healthy at discharge. Conclusions: During pregnancy, BMV by the Inoue technique is feasible, safe, and effective. There is marked symptomatic relief, along with excellent maternal and fetal outcomes.

Effects of balloon mitral valvuloplasty on left atrial function in mitral stenosis as assessed by pressure–area relation

Objectives. This study sought to investigate the changes induced on the pressure–area relation of the left atrium in patients with mitral stenosis after percutaneous balloon mitral valvuloplasty.Background. Left atrial (LA) function is influenced by changes in LA afterload. The latter is increased in mitral stenosis as a result of increased resistance to blood flow imposed by the stenotic mitral valve.Methods. We studied the effects of acute alterations of LA afterload induced by retrograde nontransseptal balloon mitral valvuloplasty (RNBMV) on LA function in patients with mitral stenosis. LA pressure–area relations were obtained in 15 patients with mitral stenosis (8 with sinus rhythm, 7 with atrial fibrillation) before and after valvuloplasty, as well as in 15 normal subjects. LA pressure was recorded by a catheter-tipped micromanometer introduced retrogradely into the left atrium while LA area was recorded simultaneously using acoustic quantification. The areas of the A and V loops of the pressure–area relation as well as the LA chamber stiffness constant were calculated.Results. Balloon valvuloplasty resulted in a significant increase in mitral valve area (p < 0.001) and a substantial reduction of the mean transmitral pressure gradient (p < 0.001) and mean LA pressure (p < 0.001). The area of the A loop in patients with sinus rhythm and the area of the V loop in those with atrial fibrillation increased significantly after completion of the procedure (p < 0.001). Furthermore, LA stiffness decreased in both groups.Conclusions. After RNBMV, there is a significant increase in LA pump function in patients with sinus rhythm, a significant increase in LA reservoir function in patients with atrial fibrillation and a significant reduction in LA stiffness in all patients. Marked alterations of the configuration of the LA pressure–area relation occur immediately after successful RNBMV in patients with mitral stenosis.

The Indian Experience of Percutaneous Transvenous Mitral Commissurotomy: Comparison of the Triple Lumen (Inoue) and Double Lumen (Accura) Variable Sized Single Balloon With Regard to Procedural Outcome and Cost Savings

The efficacy, safety, and cost of percutaneous mitral commissurotomy (PTMC), using variable volume dependent sized catheters, compared a triple lumen (Inoue) with a double lumen (Accura) catheter. PTMC was performed using Accura balloons in 400 patients and Inoue balloons in 512 patients. The group demographics, increase in mitral valve area, and incidence of significant complications were similar. The catheters were similar with respect to maneuverability and procedure (fluoroscopy) time. The Accura balloons could be reutilized statistically more often (6.3 ± 1.4 for Accura and 5.2 ± 0.8 for Inoue, P &lt; 0.05). Accura balloons were more cost‐effective, with 6.3 usages lowering the per procedural catheter cost to $214.00, while the Inoue balloons, with 5.2 usages, had a final catheter cost of $395.00. The potential savings would have been $155,340.00 if Accura balloons were utilized. Conclusions: Accura and Inoue mitral valvuloplasty balloons were comparable with regard to efficacy and safety, but the Accura balloon was significantly less costly and is therefore more suitable for use in India and other nations where resources are limited.

Balloon mitral valvuloplasty with bifoil catheter: Immediate and long‐term follow‐up results

This report documents clinical and hemodynamic benefits of balloon mitral valvuloplasty (BMV) using a bifoil balloon catheter from a single center in 415 consecutive cases of rheumatic mitral stenosis (MS). The procedure was successful in 396 (95.2%) patients, with an increase in mitral valve area (MVA) from 0.82 ± 0.35 cm2 to 2.21 ± 0.24 cm2 (P < 0.001). There were 2 (0.48%) in-hospital deaths, and 6 (1.44%) patients developed acute mitral regurgitation. The procedural and fluroscopy time was reduced significantly from 52 ± 11 and 38 ± 6 min to 33 ± 7 and 19 ± 5 min, respectively, after modifications of technique in our last 326 cases. The bifoil balloon catheter technique is safe and effective, and provides excellent hemodynamic benefits which are sustained at long-term follow-up. This technique should be considered as an addition to the existing armamentarium of interventional cardiologists performing mitral balloon valvuloplasty. Cathet. Cardiovasc. Diagn. 43:43–47, 1998. © 1998 Wiley-Liss, Inc.

Balloon mitral valvuloplasty with bifoil catheter: immediate and long-term follow-up results.

This report documents clinical and hemodynamic benefits of balloon mitral valvuloplasty (BMV) using a bifoil balloon catheter from a single center in 415 consecutive cases of rheumatic mitral stenosis (MS). The procedure was successful in 396 (95.2%) patients, with an increase in mitral valve area (MVA) from 0.82+/-0.35 cm2 to 2.21+/-0.24 cm2 (P < 0.001). There were 2 (0.48%) in-hospital deaths, and 6 (1.44%) patients developed acute mitral regurgitation. The procedural and fluroscopy time was reduced significantly from 52+/-11 and 38+/-6 min to 33+/-7 and 19+/-5 min, respectively, after modifications of technique in our last 326 cases. The bifoil balloon catheter technique is safe and effective, and provides excellent hemodynamic benefits which are sustained at long-term follow-up. This technique should be considered as an addition to the existing armamentarium of interventional cardiologists performing mitral balloon valvuloplasty.

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.

Exercise Doppler echocardiography in conjunction with right heart catheterization for the assessment of mitral stenosis.

A new diagnostic approach is reported, which combines Doppler echocardiography and a thermodilution technique for the calculation of mitral valve area at rest and during exercise. This method was applied to determine the magnitude of mitral valve reserve (= exercise-induced increase of mitral valve are) and to assess the hemodynamic relevance of mitral stenosis. 69 patients with mitral stenosis were included in this study. A Swan-Ganz catheter was used to measure exercise hemodynamics and transvalvular flow by a thermodilution technique. The mean transmitral flow velocity vmean was determined by continuous wave Doppler. Measurements were performed simultaneously at rest and during stepwise bicycle ergometry. Effective mitral valve area was calculated according to the continuity equation method (MVACE = Flow/vmean). A significant exercise-induced increase of mitral valve area was found in the total group (rest-->25 W: 1.1 +/- 0.3-->1.3 +/- 0.4 cm2, p < 0.001). Two subgroups were defined according to the presence or absence of mitral valve reserve: delta MVA > and = 20%: group A (n = 30); delta MVA < 20%: group B (n = 39). Both groups did not differ with regard to mitral valve area at rest. However, the increase of cardiac output and stroke volume was significantly higher in group A than in group B. An effective mitral valve area at 25 W of less than 1.2 cm2 had an 80% sensitivity and an 83% specificity to detect a severe mitral stenosis. Because the presence and extent of mitral valve reserve cannot be predicted under resting conditions measurements under flow-increasing interventions are necessary. Our data demonstrate that exercise Doppler in conjunction with right-sided cardiac catheterization is most useful to determine mitral valve reserve and to assess the hemodynamic relevance of mitral stenosis.

Early assessment by transesophageal echocardiography of left atrial appendage function after percutaneous mitral commissurotomy

Thirty-seven consecutively admitted patients with severe mitral stenosis underwent percutaneous mitral commissurotomy with a transthoracic and biplane or multiplane transesophageal echocardiographic examination before and between 24 and 48 hours after percutaneous mitral commissurotomy. Thirty patients (81%) were in sinus rhythm and 7 were in atrial fibrillation. Left atrial appendage (LAA) function was evaluated in both the transverse and the longitudinal planes by planimetry and pulsed Doppler echocardiographic interrogation at the LAA outlet. Percutaneous mitral commissurotomy resulted in a twofold increase in mitral valve area, and no severe mitral regurgitation occurred. With use of the planimetry method, there was no significant improvement in LAA ejection fraction, except in the transverse plane for patients in sinus rhythm (p = 0.03). With use of Doppler method, 3 distinct flow patterns were observed before the procedure: a “sinus pattern” in patients in sinus rhythm, and a “fibrillatory pattern” (n = 3) or a “no-flow pattern” (n = 4) in patients in atrial fibrillation. After commissurotomy, mere was a marked increase in LAA peak Doppler velocity (+62%) and in LAA velocity time integral (+31%). Of the 4 patients in atrial fibrillation with a no-flow pattern, 2 had recovery of a typical effective fibrillatory flow pattern after the procedure. The increase in peak Doppler velocity after commissurotomy was related to the decrease or regression in left atrial spontaneous echo contrast, and correlated with the increase in mitral valve area, the decrease in transmitral pressure gradient, and the increase in cardiac index; improvement in valve function after successful percutaneous mitral commissurotomy is associated with early improvement in LAA function.

Lack of correlation between haemodynamic and cardiopulmonary exercise capacity improvement after catheter-balloon mitral valvuloplasty.

The long-term effects of percutaneous transvenous mitral commissurotomy on exercise capacity and ventilation were investigated to determine whether a dissociation between haemodynamic improvement and exercise capacity increase occurs in patients with mitral stenosis. Eighteen patients aged 45 +/- 12.3 years (mean +/- SD) with symptomatic mitral stenosis performed a symptom-limited bicycle exercise test while respiratory gases were measured before and 6 months after percutaneous transvenous mitral commissurotomy. The mitral valve area increased from 1.07 +/- 0.22 to 1.98 +/- 0.67 cm2. P < 0.0001 and the mean mitral gradient decreased from 12.9 +/- 4.5 to 5.3 +/- 4.8 mmHg, P < 0.001, without a significant increase in cardiac output index (from 2.64 +/- 0.55 to 2.77 +/- 0.561, min-1, m-2, P = ns). This haemodynamic improvement was still present at the 6-month follow-up catheterization. Mean exercise workload and peak oxygen uptake increased 6 months after percutaneous transvenous mitral commissurotomy from 88.3 +/- 28.1 to 97.8 +/- 25.1 watts, P = 0.01, and from 18.1 +/- 5.3 to 19.9 +/- 4.8 ml. kg-1. min-1, P < 0.05. Total ventilation, ventilatory equivalents and oxygen pulse at the end of the exercise test remained unchanged. Correlations between peak oxygen or exercise capacity improvement and mitral valve area increase were poor (r = 0.27, P = ns, r = 0.24, P = ns). This clear dissociation between haemodynamic improvement and improvements in minor exercise capacity after percutaneous transvenous mitral commissurotomy suggests that peripheral alterations persist. Future studies in which patients are trained after valvuloplasty may be helpful.

Can an echocardiographic score predict who will benefit clinically from balloon dilation of the mitral valve?

Deciding whether a patient with sub-optimal mitral valve anatomy will benefit from percutaneous mitral valvotomy remains a demanding clinical problem. We assessed the ability of an established echo score applied to transoesophageal images to predict absolute increases in mitral valve area and improvement in exercise capacity. Twenty five consecutive patients undergoing routine percutaneous mitral valvotomy were studied. Changes in exercise tolerance were measured by serial cardiorespiratory treadmill exercise testing. Before the procedure, exercise duration was directly related to mitral valve area ( r s = 0.44, P < 0.05). Following percutaneous mitral valvotomy there was an increase in valve area (0.9 ± 0.2 to 1.4 ± 0.3 cm 2, P < 0.0001) and repeat exercise testing demonstrated increases in exercise duration (470 ± 220 to 610 ± 240 s, P < 0.001) and peak VO 2 (12.6 ± 4.2 to 15.1 ± 4.5 ml/kg/min, P < 0.01). There was an inverse correlation between the echo score and the increase in valve area ( r s = −0.52, P < 0.05) but no relationship between the echo score and the increase in exercise duration or peak minute oxygen consumption (V O 2 ). These data demonstrate that a score applied to transoesophageal images echocardiographic images can predict changes in mitral valve area but that the score fails to predict functional improvement for an individual patient. This suggests, therefore, that patients without contraindications to valvotomy whose valves have a high echo score should still be considered for valvotomy as they may benefit considerably from the procedure.

Exercise capacity and skeletal muscle structure and function before and after balloon mitral valvuloplasty

This study evaluated the effects of balloon mitral valvuloplasty (BMV) on exercise capacity and skeletal muscle structure and function in 10 subjects with mitral stenosis (mean age ± SD 33 ± 5.5). Measurements were obtained before, and 2 weeks and 4 months after BMV to provide baseline data, to examine the effects of improved hemodynamics, and to examine the effects of resumption of normal physical activity, respectively. Valvuloplasty caused an increase in mitral valve area (0.89 ± 0.04 to 1.75 ± 0.07 cm 2; mean ± SE), and an increase in resting cardiac output (3.8 ± 0.18 to 4.6 ± 0.19 L/min, p < 0.05). At early follow-up after 2 weeks, subjects did more work (31% increase, p < 0.01) and had greater maximal oxygen consumption (11% increase, p < 0.01). However, measurements reflecting skeletal muscle histology, biochemistry, and function were unaltered at this stage. Four months after BMV, subjects had a further increase in exercise capacity compared with both baseline (58% increase, p < 0.01) and early follow-up (20% increase, p < 0.05). There were associated late increases compared with baseline in quadriceps cross-sectional area (66 ± 5.8 vs 61 ± 5.5 cm 2, p < 0.05) and torque production (125 ± 14 vs 118 ± 16 Nm, p < 0.05). The percentage of slow twitch type I fibers increased compared with baseline (41 ± 2.0% vs 33 ± 3.1%, p < 0.05), as did the size of type II fibers (5.9 ± 0.49 vs 4.9 ± 0.57 μm 2 × 10 3, p < 0.05). Citrate synthase activity at late follow-up was also greater than it was before BMV (193 ± 32.1 vs 131 ± 16.2 nmol/mg/min, p < 0.05), although cytochrome oxidase activity remained unaltered. Thus, skeletal muscle abnormalities are found in patients with mitral stenosis. An early increase in exercise capacity occurs after BMV without changes in skeletal muscle structure and biochemistry. However, longer term improvements in exercise performance are associated with alterations in skeletal muscle.

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

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

The value of transesophageal echocardiography in predicting immediate and long-term outcome of balloon mitral valvuloplasty: comparison with transthoracic echocardiography.

The purpose of this study was to assess the role of transesophageal echocardiography in predicting the immediate and long-term outcome of balloon mitral valvuloplasty, and compare the results to transthoracic echocardiography. Transesophageal echocardiography accurately detects left atrial thrombi and allows better visualization of mitral valve morphology; however, its value in predicting the immediate and long-term outcome of balloon mitral valvuloplasty had not been assessed as adequately as for transthoracic echocardiography. In 56 patients referred for balloon mitral valvuloplasty, both transesophageal and transthoracic echocardiography were performed (Group A). An echo score for both techniques was used to reflect mitral valve morphology, and its predictive value for immediate and long-term outcome of the valvuloplasty was assessed. The impact of transesophageal echocardiography in preventing procedural embolic events in those 56 patients was assessed by comparison to another group of 41 patients, who were examined only by transthoracic echocardiography prior to balloon mitral valvuloplasty (Group B). In Group A, transesophageal echocardiography detected left atrial thrombus in seven, while transthoracic echocardiography detected left atrial thrombus in two patients. After 2 months of warfarin therapy, a repeat transesophageal echo examination in four patients showed resolution of thrombus in three who went on to have balloon mitral valvuloplasty. Among the 52 patients who eventually had the procedure after thrombus was excluded by transesophageal echocardiography, there were no embolic events, compared to three embolic events among the 41 patients in Group B (P = 0.08). The transthoracic echocardiography scores, while slightly higher, correlated well with transesophageal echocardiography scores (r = 0.51, P < 0.001). The increase in mitral valve area did not correlate well to total transthoracic or transesophageal echocardiography scores, while it correlated negatively to valve calcification by transthoracic (r = -0.29, P < 0.05) and mobility by transesophageal echocardiography (r = -0.59, P < 0.02). At follow-up (7 +/- 4 months) nonsurvivors (7/56) had higher total scores by either transthoracic (P < 0.01) or transesophageal echocardiography (P < 0.05) compared to survivors. The percent reduction in mitral valve area was greater with age (r = 0.5, P < 0.02), time to follow-up (r = 0.67, P < 0.002), valve mobility by transthoracic echocardiography (r = 0.59, P < 0.01), and valve calcification by transthoracic echocardiography (r = 0.37, P = 0.09) and transesophageal echocardiography (r = 0.4, P = 0.07). Transesophageal echocardiography is superior to transthoracic echocardiography in detecting left atrial thrombi, and it may reduce the risk of embolic events following balloon mitral valvuloplasty. Assessment of mitral valve morphology by transesophageal echocardiography is complementary and not superior to assessment by transthoracic echocardiography. Mitral valve calcification and mobility appear to be the best morphological predictors of immediate and long-term outcome following balloon mitral valvuloplasty.

Significant tricuspid regurgitation is a marker for adverse outcome in patients undergoing percutaneous ballon mitral valvuloplasty

Objectives, This study examined the association between the presence of tricuspid regurgitation and immediate and late adverse outcomes in patients undergoing balloon mitral valvuloplasty.Background. Significant tricuspid regurgitation has an adverse impact on morbidity and mortality in patients undergoing mitral valve surgery for mitral stenosis.Methods. We studied 318 consecutive patients (mean [± SD] age 54 ± 15 years) who underwent ballon mitral valvuloplasty and had color Doppler ecnocardiographic studies before the procedure. Patients were classified into three groups: 221 with no or mild (69%), 60 with moderate (19%) and 37 with severe (12%) tricuspid regurgitation. Clinical follow-up ranged from 6 to 62 months.Results. Before mitral valvuloplasty, increasing degrees of tricuspid regurgitation were associated with a smaller initial mitral valve area (p < 0.05), higher echocardiographic score (p < 0.05), lower cardiac output (p < 0.01) and higher pulmonary vascular resistance (p < 0.01). Although the initial success rate did not differ significantly between groups, patients with a higher degree of tricuspid regurgitation had less optimal results, as reflected by a smaller absolute increase in mitral valve area (1.02 vs. 0.9 vs. 0.7 cm2, p < 0.01). The estimated 4-year event-free survival rate (freedom from death, mitral valve surgery, repeat valvuloplasty and heart failure) was lower for the group with severe tricuspid regurgitation (68% vs. 58% vs. 35%, p < 0.0001). At 4 years, 94% of patients with mild tricuspid regurgitation were alive compared with 90% and 69%, respectively, of patients with moderate or severe tricuspid regurgitation (p < 0.0001). Cox proportional analysis identified tricuspid regurgitation as an independent predictor of late outcome (p < 0.001).Conclusions. Patients with mitral stenosis and severe tricuspid regurgitation undergoing mitral valvuloplasty have advanced mitral valve and pulmonary vascular disease, suboptimal immediate results and poor late outcome.

Percutaneous transatrial mitral commissurotomy: Immediate and intermediate results

Objectives. The purpose of this study was to evaluate the immediate and follow-up results of percutaneous transatrial mitral commissurotomy in 600 patients with rheumatic mitral stenosis.Background. Percutaneous transatrial mitral commissurotomy has emerged as an effective nonsurgical technique for patients with symptomatic mitral stenosis. Several studies have shown that the Immediate results are comparable to closed and open mitral valvotomy.Methods. Percutaneous transatrial mitral commissurotomy was performed in 600 patients with rheumatic mitral stenosis by the double-balloon (290 patients [48.3%]) and Row-guided inoue balloon (310 patients [51.7%]) techniques. There were 154 male (25.6%) and 446 female (77.4%) patients with a mean [±SD] age of 27 ± 8 years (range 8 to 60). Atrial fibrillation was present in 26 patients (4.3%), mitral regurgitation ≤ grade 2 in 62 (10.3%) and densely calcific valve in 12 (2%). All patients had clinical and echocardiographic (two-dimensional, continuous wave Doppler, color flow imaging) follow-up at 3-month intervals.Results. Percutaneous transatrial mitral commissurotomy was successful in 589 patients (9S.1%), and optimal commissurotomy was achieved in 562 (93.6%), with an increase in mitral valve area from (mean ± SD) 0.75 ± 0.18 to 2.2 ± 0.38 cm2(p < 0.001) and a decrease in transmitral end-diasiolic gradient front 27.3 ± 6.1 to 3.8 ± 4.2 mm Hg (p < 0.001). Mitral regurgitation developed or increased in 208 patients (34.6%). Six patients (1%) with mitral régurgitation required mitral valve replacement. Cardiac tarnponade occurred in 8 patients (1.3%). Six patients (1%) died. Restenosis developed in 10 patients (1.7%) during a mean follow-up period of 37 ± 8 months (range 6 to 66).Conclusions. Percutaneous transatrial mitral commissurotomy is an effective, safe procedure with gratifying intermediate results. It should be considered the treatment of choice for rheumatic mitral stenosis.

Effect of exercise on valvular resistance in patients with mitral stenosis

Objectives. This exercise study assessed the relation between valvular resistance and flow in patients with mitral stenosis.Background. Valvular resistance has been proposed as an alternative measue of stenotic valvular lesions, which is speculated to remain stable under changing hemodynamic conditions.Methods. In 35 of 40 patients with pure or predominant mitral stenosis, continuous wave Doppler measurements of the mitral stenotic jet were possible at rest and during supine bicycle ergometry. Simultaneously, transvalvular flow was assessed by thermodilution technique. For calculation of valvular resistance, the mean mitral valve pressure gradient was determined according to the simplified Bernoulli equation and divided by transvalvular flow. Additionally, effective mitral valve area was calculated according to the continuity equation method, dividing flow by the mean diastolic low velocity.Results. Valvular resistance was 65 ± 32 dynes · s · cm−5at rest and increased to 82 ± 43 dynes · s · cm−5at 25 W (p < 0.001). The most prominent increase in valvular resistance (rest to 25 W 63 ±28 to 95 ± 48 dynes · s · cm−5, p < 0.001) was found in those patients who had no or only a moderate (< 20%) change in effective mitral valve area. In contrast, valvular resistance remained constant (67 ± 36 vs. 70 ± 32 dynes · s · cm−5) in patients with significant (≥ 20%) increase in mitral valve area with exercise.Conclusions. In patients with mitral stenosis, the exercise induced change in valvular resistance are heterogeneous. This is the result of the variable response of mitral valve area to an increase in flow. In the individual patient, mital valve area can significantly increase, a factor that has to be taken into account when interpreting the hemodynamic relevance of the obstruction. Calculated valvular resistance is flew dependent and has no advantage over valve area calculation for quantifying stenosis.

Results of percutaneous balloon mitral valvotomy in young adults

The results of percutaneous balloon mitral valvotomy (PBMV) were evaluated in 235 young patients (mean age 29 ± 11 years) with symptomatic rheumatic mitral stenosis, and the single-balloon Inoue technique was compared with the double-balloon Mansfield technique. PBMV was associated with a significant increase in Gorlin mitral valve area (0.78 ± 0.23 to 1.61 ± 0.64 cm 2; p < 0.001), and improvement in New York Heart Association functional class (2.78 ± 0.59 to 1.28 ± 0.58; p < 0.001). Mitral regurgitation increased significantly (0.4 ± 0.6 to 1.3 ± 1.0; p < 0.001), but was significant (≥3+) only in 19 patients (8%). Comparison of the Inoue and Mansfield techniques showed a significantly lower Gorlin mitral valve area after PBMV (1.55 ± 0.56 vs 1.74 ± 0.74 cm 2; p < 0.05), but a lower incidence of mitral regurgitation by color Doppler echocardiography (1.1 ± 0.7 vs 1.5 ± 0.8; p < 0.05) in the Inoue group. Patients were divided into those with nonpliable (valve score >8; group I) and pliable (score ≤ 8; group II) valves. Although significant increases in mitral valve area were obtained in both groups, mitral valve area by planimetry was significantly lower in group I (1.49 ± 0.46 vs 1.86 ± 0.44 cm 2; p < 0.05), whereas there was no difference in the amount of color Doppler mitral regurgitation (1.5 ± 1.0 vs 1.2 ± 0.7; p = NS). It is concluded that (1) in young patients with mitral stenosis, PBMV offers excellent palliation even in those with less ideally pliable valves; and (2) although the Inoue technique achieves smaller valve areas, it is accompanied by a lower incidence of mitral regurgitation.

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.

Balloon mitral commissurotomy for mitral restenosis after surgical commissurotomy

Balloon mitral commissurotomy (BMC) was performed in 113 patients. Of these patients, 27 (24%) (25 women and 2 men, aged 49 ± 13 years) had recurrent mitral stenosis 13 ± 6 years (range 5 to 29) after surgical Commissurotomy. Eleven patients (41%) were considered at high risk for surgery. BMC resulted in an increase in mitral valve area from 1.1 ± 0.3 to 1.9 ± 0.7 cm 2 (p < 0.0001), and a decrease in mean mitral gradient from 16 ± 7 to 6 ± 3 mm Hg (p < 0.0001). An optimal result of BMC (increase in valve area ≥25% with a post-BMC valve area ≥1.5 cm 2) was obtained in 18 patients (67%). The results did not differ from those observed in the 86 patients of our entire series without prior surgical Commissurotomy. Patients with an optimal result of BMC had a more recent surgical Commissurotomy and lesser morphologic alterations of the mitral valve than did those with a nonoptimal result. Patients with echocardiographic scores <10 had an 80% success rate of BMC; however, this rate decreased to 29% for those with scores ≥10. One patient (4%) died from a cerebrovascular accident. Clinical follow-up at 1 year showed persistent clinical improvement in 89% of patients with an optimal result of BMC; 72% were in New York Heart Association class I and 17% in class II. Thus, BMC is a safe and effective short- and long-term procedure for patients with mitral restenosis after surgical commissurotomy; because of its percutaneous approach, avoiding the risks associated with a second thoracotomy, BMC can be considered the treatment of choice in these patients.

Relation of balloon size to outcome after balloon mitral valvotomy with single and double cylindrical balloons

Balloon size for balloon mitral valvotomy (BMV) must be chosen with care in order to achieve optimal increase in mitral valve area without significant regurgitation. Previous workers have suggested optimal ranges for the effective balloon dilating area indexed to body surface area. 1 Oversizing of balloons was found to be associated with the development of mitral regurgitation. We present our experience regarding the relation between balloon size and the outcome of BMV in Indian patients. We analyzed the records of 69 patients who underwent BMV by a cylindrical balloon technique at our institution from 1985 to 1991. The patients were aged 21.9 ± 6.7 years, 47 women (71%) and 19 men (29%). No patient had significant subvalvular deformity on echocardiography.