Short- and long-term results of catheter balloon percutaneous transvenous mitral commissurotomy

Balloon valvuloplasty during pregnancy

Although rheumatic diseases are reported to be almost eradicated in the developed countries, they still continue to contribute significantly to maternal mortality in the developing world. Surgical therapies need to be considered for those patients who do not respond satisfactorily to medication. However, valve replacement or valvulotomy during pregnancy carries significant risks for both the mother and the fetus. Two patients with severe mitral stenosis refractory to medical therapy are presented. Both patients were subjected to percutaneous balloon valvuloplasty during pregnancy without any complications. They were able to discontinue medication and deliver vaginally at term. Balloon valvuloplasty appears to be a safe alternative to conventional surgical approaches in pregnancy.

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.

Immediate and late outcome of percutaneous balloon mitral valvotomy in patients with significantly calcified valves

We assessed immediate and late outcome in 55 patients with significantly calcified valves (group 1) after balloon mitral valvotomy and compared the results with those from 60 patients with noncalcified or minimally calcified valves (group 2). After valvotomy, mitral valve area increased from 1.03 +/- 0.30 cm2 to 1.64 +/- 0.35 cm2 (p = 0.0001) by echo planimetry in group 1 but was significantly smaller than the mitral valve area in group 2 after valvotomy (1.94 +/- 0.38 cm2; p = 0.0001). At a mean follow-up period of 30 months (range 2 to 81 months), 51% of patients in group 1 and 83% in group 2 were symptom free (p = 0.0002). In group 2, 15 (27%) patients and in group 2, 4 (7%) patients had cardiac events (p = 0.003). The risk ratio for cardiac events was 4.3 times greater in group 1 than in group 2. In group 1, the risk ratio for cardiac events was 3.2 times higher in patients age > or = 65 years and in patients with atrial fibrillation. The 6-year cumulative cardiac event-free survival rate was 64% in group 1 and 90% in group 2 (p = 0.005). In 75 (65%) patients who had follow-up echocardiographic study (35 in group 1 and 40 in group 2), mitral valve area decreased to 1.48 +/- 0.42 cm2 at follow-up in group 1 (p < 0.01) and to 1.77 +/- 0.50 cm2 in group 2 (p = 0.3). Restenosis occurred in 16 (46%) of 35 patients in group 1 and 10 (25%) of 40 in group 2 (p = 0.06).(ABSTRACT TRUNCATED AT 250 WORDS)

Clinical follow-up of patients undergoing percutaneous mitral balloon valvotomy

BACKGROUND

This study is the clinical follow-up (20 +/- 12 months; range, 6 to 49 months) of 327 patients who had percutaneous mitral balloon valvotomy (PMV) at the Massachusetts General Hospital.

METHODS AND RESULTS

There were seven in-hospital deaths. Patients were divided into two groups according to their echocardiographic score; 211 patients had echocardiographic scores < or = 8 and 116, echocardiographic scores > 8. Patients with echocardiographic scores > 8 were older (64 +/- 11 versus 48 +/- 14 years, P < .01), and more had atrial fibrillation (65% versus 40%, P < .01), calcium under fluoroscopy (81% versus 29%, P < .01), and previous surgical commissurotomy (30% versus 16%, P < .01) than patients with echocardiographic scores < or = 8. With PMV, mitral valve area increased from 1.0 +/- 0.3 to 2.2 +/- 0.8 cm2 in patients with echocardiographic scores < or = 8 and from 0.8 +/- 1 to 1.7 +/- 0.7 cm2 in those with echocardiographic scores > 8. Rates of survival (98 +/- 2% versus 72 +/- 11%), survival with freedom from mitral valve replacement (91 +/- 4% versus 55 +/- 13%), and survival with freedom from combined events (79 +/- 10% versus 39 +/- 18%) at follow-up were greater in patients with echocardiographic scores < or = 8 (P < .00005). Cox regression analysis identified the echocardiographic score as the most important unfavorable intermediate long-term follow-up prediction factor after PMV.

CONCLUSIONS

The excellent intermediate long-term clinical follow-up of patients with echocardiographic score < or = 8 and no calcified mitral valves suggests that PMV may be the treatment of choice in this group of patients.

The value of transthoracic echocardiography during percutaneous balloon mitral valvuloplasty

Percutaneous balloon mitral valvuloplasty is a standard alternative to surgery in a selected group of patients with symptomatic dominant rheumatic mitral stenosis. With careful transthoracic and transesophageal echocardiographic selection of patients, there is a low complication and high success rate. Echocardiography has also been established as extremely useful in the long-term follow-up of patients. We present four cases that highlight our view that transthoracic echocardiography should be performed during the procedure, after each balloon inflation, and before and after the intervention. In our experience transthoracic echocardiography during balloon mitral valvuloplasty is invaluable in assessing commissural separation, increasing mitral valve area, new mitral regurgitation, and occasional unexpected anatomic sequelae of balloon inflation.

Percutaneous transvenous mitral commissurotomy for restenosis after surgical mitral valvotomy

Percutaneous transvenous mitral commissurotomy (PTMC) was performed in 350 patients. Of these patients, 51 (15%) (30 women and 21 men, aged 32 +/- 11 years) had restenosis 11 +/- 4 years following surgical valvotomy. Forty (79%) patients were in New York Heart Association (NYHA) class III and 11 (21%) were in class IV. PTMC resulted in an increase in mitral valve area from 0.82 +/- 0.3 to 1.9 +/- 0.2 cm2 (p < 0.001), an increase in cardiac index from 1.9 +/- 0.4 to 2.8 +/- 0.5 l/min/m2 (p < 0.001), and a decrease in mean transmitral gradients from 29 +/- 4 to 6 +/- 4 mmHg (p < 0.001). The results did not differ from those observed in 299 patients without prior surgical valvotomy. On univariate analysis, the subvalvular fibrosis, assessed angiographically, and the duration from prior surgery were not found to influence the overall outcome. At 24 weeks, 46 of 48 (96%) patients in whom clinical follow-up was available, were found to be in NYHA class I and 2 (4%) patients were in class II. Thus, PTMC is a safe and effective procedure for patients with mitral restenosis following surgical valvotomy.

A simple balloon-sizing method in Inoue-balloon percutaneous transvenous mitral commissurotomy

This study was carried out to examine whether the previously determined balloon sizing method based on patient height was valid for percutaneous transvenous mitral commissurotomy using the current second-generation Inoue balloon catheter. The study consisted of 70 patients with pliable noncalcified mitral valves (group 1) and 85 patients with calcified mitral valves and/or severe subvalvular lesions (group 2). The mitral valve area was increased more in group 1 than in group 2 (1.0 +/- 0.3 to 1.9 +/- 0.5 cm2 versus 1.0 +/- 0.3 to 1.6 +/- 0.5 cm2, P = 0.002). Using the stepwise dilatation technique, none of the group 1 patients developed severe mitral regurgitation. Severe mitral regurgitation occurred in 4 patients (4.7%) in group 2. In conclusion, a simple balloon sizing method based on body height for selection of an appropriate-sized balloon catheter, as well as an initial inflated balloon diameter for the stepwise dilatation technique is useful for optimal acute outcomes in mitral commissurotomy.

Percutaneous transvenous mitral commissurotomy in 390 cases using the Inoue balloon catheter

Percutaneous transvenous mitral commissurotomy using the Inoue technique was performed in 390 cases of rheumatic mitral stenosis. There were 220 (56%) females and 170 (44%) males. The age range was 9-47 years [mean +/- S.D., 26 +/- 14) and all were symptomatic (New York Heart Association (NYHA) class II in 23 (6%); class III in 280 (72%); and class IV in 87 (22%) patients]. Mitral valve area increased from 0.6 +/- 0.4 to 2 +/- 0.7 cm2, mean transmitral gradients decreased from 26 +/- 8 to 5 +/- 3 mmHg and cardiac index improved from 2.2 +/- 0.8 to 3.0 +/- 0.7 l/min/m2 (P < 0.001). There were no procedure related deaths. An increase in mitral regurgitation by one grade was observed in 40 (10%) cases, with 8 (2%) cases developing severe mitral regurgitation. Oximetry evidence of left to right atrial shunt (Qp/Qs > or = 1.5:1) was observed in 11 (3%) patients. Four (1.0%) patients developed cardiac tamponade, none had thromboembolism. Follow-up of 290 cases at 26 +/- 5 weeks showed persistent improvement in clinical (NYHA class I in 98%) and echocardiographic mitral valve area. Percutaneous transvenous mitral commissurotomy is safe, easy to perform and provides excellent clinical and hemodynamic benefit in the majority of cases.

Mitral balloon valvuloplasty by Inoue technique without echocardiographic standby

Mitral balloon valvuloplasty (MBV) by Inoue technique was performed in 85 patients with symptomatic rheumatic mitral stenosis (MS). Twenty-eight patients were male and 57 patients were female. The age range was nine to 59 years (mean 28). All patients were subjected to echocardiographic and Doppler examinations before and one day after the procedure. The first 57 patients were subjected to exercise tolerance tests (ETT) a few days before and a few days after the procedure. An echocardiographic score was measured regarding valve thickening, leaflet mobility, degree of calcification and the severity of involvement of subvalvular apparatus. The mitral valve area (MVA) increased from 0.9 +/- 0.2 cm2 to 1.9 +/- 0.45 cm2, (P<0.0001). The mitral gradient (MG) decreased from 20 +/- 5.8 mm/Hg to 5.05 +/-+ 3.2 mm/Hg (P<0.0001). Mean left atrial pressure (LAP) dropped from 25.85 +/- 8.4 mm/Hg to 11.05 +/- 5.4 mm/Hg (P<0.0001). Exercise tolerance test (ETT) increased from 5.59 +/- 1.3 to 11.75 +/- 1.48 min. (P<0.0001). Complications included severe mitral regurgitation (MR) in two patients (2.3%). In the first 57 patients, mild left-to-right shunt measured by green dye dilution technique had occurred in 40% of patients. In conclusion, MBV by Inoue balloon is a good alternative to surgical commissurotomy and echocardiographic standby is very helpful when it is available. However, MBV can be safely performed if echocardiography is inaccessible.

Influence of subvalvular fibrosis on results and complications of percutaneous mitral commissurotomy with use of the Inoue balloon

In 136 consecutive patients who underwent percutaneous transvenous mitral commissurotomy (PTMC) with use of the single rubber-nylon (Inoue) balloon Inoue balloon angiographically analyzed subvalvular fibrosis was assessed retrospectively with regard to results and complications. There were 53 males and 83 females, with a mean age of 22 +/- 11 years (range 10 to 48 years). For the entire group, mitral valve area increased from 0.7 +/- 0.3 to 2.1 +/- 0.6 cm2 (p < 0.001). Valve area increased from 0.7 +/- 0.12 to 1.8 +/- 0.14 cm2 in patients with severe subvalvular fibrosis (n = 55) and from 0.8 +/- 0.11 to 1.9 +/- 0.12 cm2 in cases with mild to moderate subvalvular fibrosis (n = 80; p = NS). The number of patients with 2+ or greater increase in mitral regurgitation was not different between the two groups (6% vs 5.5%, p = NS). None of the patients required mitral valve replacement immediately after PTMC. We conclude that, with use of the Inoue balloon, PTMC can be successfully performed in patients with severe subvalvular fibrosis.

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 flow-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 < or = 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 (98.1%), 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-diastolic gradient from 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 regurgitation required mitral valve replacement. Cardiac tamponade 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.

Percutaneous transseptal mitral valvuloplasty in the presence of atrial septal aneurysm

We demonstrate the feasibility and efficacy of Inoue balloon valvuloplasty in two patients with the rare combination of mitral stenosis and atrial septal aneurysm. Following the procedure, the mitral valve area increased from 1.3 cm2 to 2.7 cm2 and 1.2 cm2 to 2.6 cm2, respectively, with no major complications encountered.

Urgent/emergent percutaneous transvenous mitral commissurotomy

Urgent/emergent percutaneous transvenous mitral commissurotomy (PTMC) was performed in 10 patients (two men and eight women, aged 21 to 60 yr). All patients had arterial hypoxemia and four required mechanical respirators. PTMC was performed in the semi-recumbent position in four patients. The seven patients with pliable valves (group 1) achieved good hemodynamic and echocardiographic results after PTMC, but one died 2 wk later because of sepsis complicating preexisting pneumonitis. The two pregnant patients uneventfully delivered normal babies at term. There was continued clinical improvement in the six surviving patients at last follow-up at 11 to 39 mon (median 26). Of the three patients with calcified valves and severe subvalvular lesions (group 2), the premoribund patient in whom last-resort PTMC created severe mitral regurgitation died 3 days later of multiple organ failure. The other two patients underwent mitral valve replacement 1-6 days later because of lack of clinical improvement due to creation of severe mitral regurgitation and ineffective mitral valve dilation, respectively. In conclusion, urgent/emergent PTMC is feasible and safe. However, its outcomes are dictated by the status of diseased mitral valve and coexisting illness.

Pulmonary hemodynamics at rest and effort, 6 and 12 months after mitral valve replacement: a slow regression of effort pulmonary hypertension

An analysis of pulmonary hemodynamics in 22 patients with postrheumatic mitral valve disease using a floating Swan-Ganz type catheter at rest and effort in supine cycloergometer test was done before, 6 and 12 months after mitral valve replacement. Pulmonary hemodynamics data were recorded and calculated at rest and during effort. The most significant changes in almost all analyzed parameters occurred between preoperative and 6 month examination values. However further modest changes mainly during effort were observed between the 6-month and 1-year follow-ups. The mean workload during the bicycle ergometer test rose significantly from 22 +/- 26 W before to 48 +/- 20 W at 6 months and 57 +/- 22 W at 12 months after mitral valve replacement (P < 0.005). We noted a significant improvement in functional class 6 months after mitral valve replacement and a further slight improvement 12 months after. There was a small statistically insignificant decrease in systolic pulmonary pressure between 6 and 12 month measurements. Systolic pulmonary pressure at rest dropped slightly from 39.0 +/- 9.4 to 34.6 +/- 9.4 mmHg. During the bicycle test after 3 min (25 W) the decrease of systolic pulmonary pressure between the 6- and 12-month measurements was statistically significant. Systolic pulmonary artery pressure dropped from 61 +/- 12.4 to 50 +/- 12.3 mmHg. At the same time the drop in pulmonary wedge pressure was smaller and statistically not significant. Pulmonary wedge pressure at rest 6 months after mitral valve replacement was 14.3 +/- 6 mmHg, and after 12 months was 12.7 +/- 4.5; at 25 W, 24.6 +/- 6 vs. 22.1 +/- 5.5, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Percutaneous transvenous mitral commissurotomy in patients with severe kyphoscoliosis

Because transseptal catheterization is felt to be contraindicated in patients with severe kyphoscoliosis, there have been no reports of percutaneous transvenous mitral commissurotomy performed in such patients. This report describes percutaneous transvenous mitral commissurotomy in three patients with severe thoracic kyphoscoliosis, with special emphasis on the transseptal puncture technique. Biplane right atrial angiography and the contrast septal flush method are very useful in landmark selection for a safe transseptal puncture.

Effects of percutaneous transluminal mitral valvuloplasty on plasma catecholamine levels during exercise

Elevation of plasma catecholamine levels during exercise in patients with mitral stenosis correlated with the severity of the disease. We investigated the plasma norepinephrine changes in six patients before and after percutaneous transluminal mitral valvuloplasty (PTMV) during continuously graded ergometer exercise. Peak exercise intensity was increased from 65.8 W to 87.5 W after PTMV. Plasma norepinephrine level at 60 W workload intensity was decreased from 2308 +/- 864 pg/ml to 841 +/- 233 pg/ml after PTMV (p < 0.05). We concluded that PTMV decreased the plasma norepinephrine level during exercise in the patients with mitral stenosis. Percutaneous transluminal mitral valvuloplasty is a novel procedure for the improvement of symptoms in patients with mitral stenosis.

Effect of percutaneous balloon mitral valvuloplasty on serum creatinine phosphokinase MB-isoenzyme levels

Twenty-one patients with moderate to severe mitral stenosis were treated with percutaneous balloon mitral valvuloplasty (PBMV) using Inoue mitral double-lumen balloon catheters. Creatinine phosphokinase MB isoenzyme (CPK-MB) levels were measured at baseline, 5 min, 6 h, and 18 h post dilatation. Haemodynamic indexes, 12-lead ECGs, and 2-dimensional echocardiograms were performed to evaluate systolic function postprocedure. CPK-MB levels were modestly increased at 5 min and at 6 h postprocedure compared with the baseline level (p < 0.001) but were still within the normal reference range, except for one patient who had a level at 5 min minimally above the upper limit of normal. CPK-MB levels were not significantly increased at 18 h after the procedure. No significant changes in ejection fractions, 12-lead ECGs, and regional wall motion occurred in any of the patients studied. In conclusion, PBMV causes modest early elevation of CPK-MB. This elevation is not associated with changes in LV systolic function and does not interfere with the diagnosis of acute myocardial infarction using the enzyme elevation criteria.

Mitral restenosis and mitral regurgitation 1 year after Inoue mitral balloon valvotomy in a population of patients with pliable mitral valve stenosis

To determine the rate of mitral restenosis and mitral regurgitation increase 1 year after mitral valvotomy using the Inoue balloon catheter, 66 consecutive patients with severe, pliable mitral stenosis had their mitral valve area (MVA) calculated by two-dimensional echocardiography (2DE) and Doppler before, immediately after balloon valvotomy, and at 1-year follow-up. Color Doppler studies were also done to detect small atrial septal defects (ASDs) and mitral regurgitation. The mean age of the patients was 31 +/- 12 years. Three patients were in New York Heart Association (NYHA) class II and 63 patients were in NYHA class III to IV. Sixty-two of the 66 patients had an echo score (Boston) of < or = 8. After Inoue balloon valvotomy (IBV), the MVA (2DE) increased from 0.8 +/- 0.2 to 1.9 +/- 0.3 cm2 (p < 0.001), and the Doppler MVA increased from 0.8 +/- 0.2 to 1.8 +/- 0.3 cm2 (p < 0.001). We detected 4 of 66 cases (6%) with significant residual mitral stenosis (MVA < 1.5 cm2). Mitral regurgitation increased in 14 of 66 patients (21%), but no patient developed severe mitral regurgitation. Fourteen out of 66 patients (20%) had ASDs that were detected on color Doppler. At 1-year follow-up the mean Doppler MVA was maintained at 1.8 +/- 0.4 cm2, with 6 of 66 patients (9%) exhibiting significant mitral valve restenosis. Residual significant mitral stenosis must be differentiated from mitral restenosis.(ABSTRACT TRUNCATED AT 250 WORDS)

Comparison of results of percutaneous balloon valvuloplasty in patients with mild and moderate mitral stenosis to those with severe mitral stenosis. The North American Inoue Balloon Investigators

Most reported studies of percutaneous balloon valvuloplasty in adults with acquired mitral stenosis have used patients with severely stenosed valves. The risks and benefits of valvuloplasty were examined in a multicenter registry of patients to determine whether balloon valvuloplasty can effectively dilate less severely obstructed valves, and to clarify the role of this procedure in symptomatic patients with mild and moderate mitral stenosis. The study groups were derived from the North American Inoue Balloon Valvuloplasty Registry. Full hemodynamic data were available in 264 patients; 45 (17%) with mild or moderate mitral stenosis (mitral valve area > or = 1.3 cm2) were compared with the remaining 219 with severe mitral stenosis (valve area < 1.3 cm2). Percutaneous balloon valvuloplasty was performed using the anterograde transseptal technique with an Inoue balloon. The mean age of patients with mild and moderate mitral stenosis was 53 +/- 13 years, and all were symptomatic with a mean New York Heart Association functional class of 2.9 +/- 0.7. Balloon valvuloplasty resulted in an increase in calculated mitral valve area from 1.4 +/- 0.1 to 2.3 +/- 0.7 cm2 (p < 0.05), and a final valve area > or = 1.9 cm2 was achieved in 37 patients (82%). There were no procedural deaths, but complications included right atrial perforation, transient ischemic attack and emergency surgery for severe mitral regurgitation. One-year follow-up evaluation revealed symptomatic improvement in most patients (mean New York Heart Association class 1.4 +/- 0.6; p < 0.0001). However, 2 patients needed repeat valvuloplasty for restenosis, and 5 had mitral valve replacements.(ABSTRACT TRUNCATED AT 250 WORDS)

Pulmonary valvuloplasty in adults using the Inoue balloon catheter

This report describes a new balloon pulmonary valvuloplasty technique using the Inoue balloon catheter performed in 14 consecutive adult patients, aged 17-47 years (mean 27). The mean right ventricular systolic pressure and the pulmonary valvular peak-to-peak systolic gradient decreased from 102 +/- 41 to 52 +/- 19 mm Hg (p = 0.001) and 81 +/- 40 to 7 +/- 7 mm Hg (p = 0.0002), respectively. An infundibular peak-to-peak systolic gradient either developed (n = 13) or increased (n = 1). None of the patients were treated with beta-adrenergic blockers before or after the valvuloplasty. Eight patients underwent repeat hemodynamic study 12-30 months (mean 17) after treatment, and had no evidence of valvular restenosis. The mean right ventricular systolic pressure and the mean infundibular peak-to-peak systolic gradient decreased, compared to the values immediately after valvuloplasty (54 to 40 mm Hg, p = 0.03, and 28 to 10 mm Hg, p = 0.03, respectively). The study suggests that pulmonary valvuloplasty in adults using the Inoue balloon catheter technique is feasible, safe, and effective.

Quantification of left-to-right atrial shunting and defect size after balloon mitral commissurotomy using biplane transesophageal echocardiography, color flow Doppler mapping, and the principle of proximal flow convergence

BACKGROUND

The flow convergence region (FCR), a zone of progressive laminar velocity acceleration, can be imaged by color Doppler proximal to stenotic and regurgitant orifices. Theoretically, FCR proximal to a discrete circular and planar orifice consists of concentric hemispheric shells of equal and accelerating velocities centered at the orifice. According to the continuity principle, flow rate across any of these isovelocity surfaces equals flow rate through the orifice. The aim of this study was to investigate whether these principles could be applied to quantify left-to-right shunting and the size of atrial septal defects after balloon mitral commissurotomy.

METHODS AND RESULTS

Biplane transesophageal echocardiography (TEE) with color flow imaging was performed on 36 consecutive patients (mean age, 57 +/- 16 years; range, 14-78 years) immediately before and within 24 hours of balloon (Inoue, n = 33; Mansfield, n = 3) mitral commissurotomy. Left-to-right atrial shunting was detected by TEE in 33 patients (92%) and by oximetry in 11 patients (31%). The radius r of FCR was measured from the first aliasing limit, at a Nyquist velocity reduced to 11 cm/sec by zero-shifting, to the orifice in the atrial septum. FCR was assumed to be hemispherical. Hence, flow rate (Q) was calculated as 2 pi r2 Vr, where Vr is the velocity at a radial distance r. The velocity profile of transatrial flow was assessed by means of high pulse repetition frequency, from which the maximum flow velocity (Vp) and the velocity-time integral (VTI) were obtained. The flow area of the atrial septal defect was calculated as Qm, the maximal flow rate, divided by Vp. Hence, shunt flow was calculated as flow area x VTI x heart rate. FCR was analyzed in two orthogonal planes. Mean Qm (38.1 +/- 26.5 versus 5.3 +/- 2.7 mL/sec), flow area (22.1 +/- 11.2 versus 4.4 +/- 2.0 mm2), and shunt flow (1,590 +/- 1,070 versus 200 +/- 130 mL/min) on transverse plane imaging were all significantly higher in patients with shunts detected by oximetry than in those without. Similar results were obtained from longitudinal plane imaging. Qm correlated well with oximetric shunt flow (r = 0.89-0.94, p < 0.001) and shunt ratio (r = 0.91-0.94, p < 0.001). Flow area correlated closely (r = 0.93-0.94, p < 0.001) with area determined by direct measurement from two-dimensional echocardiography. Shunt flow determined by FCR also correlated closely (r = 0.94-0.98, p < 0.001) with that determined by oximetry and that derived from two-dimensional echocardiography and pulsed Doppler (r = 0.96, p < 0.001).

CONCLUSIONS

The flow convergence region imaged by TEE color flow mapping provides new and accurate quantitative information on atrial shunt flow and defect size after balloon mitral valvotomy. It is a quick, reliable, and fairly simple method that can be readily incorporated into routine clinical practice.

Balloon valvotomy for mitral restenosis after open or closed surgical commissurotomy

Balloon mitral valvotomy was performed in 48 patients (Group I) with mitral restenosis following prior surgical commissurotomy 3-21 years previously. Their results were compared with those of balloon valvotomy in 302 patients without prior commissurotomy (Group II). The procedure was successful in 91.7% of Group I. The mitral valve area, cardiac output, mitral valve gradient, mean left atrial and pulmonary arterial pressures significantly improved following valvotomy (all P < 0.001) in Group I and similar results were obtained in Group II. A comparison of the absolute and percentage change in the mitral valve area following valvotomy amongst the two groups revealed no significant difference (P = N.S.). The baseline clinical characteristics in both the groups were similar except for a higher echocardiographic score (8.64 +/- 1.5 vs. 7 +/- 1.7; P < 0.005) in Group I. Despite the high echo score, achievement of an 'optimal' result and occurrence of postprocedural mitral regurgitation were similar in both groups. The complications included systemic embolus in one patient and increase in mitral regurgitation to > or = 2+ in 2. There were no deaths. Balloon valvotomy for mitral restenosis following surgical commissurotomy is safe, effective and produces clinical and hemodynamic results comparable to those in unoperated cases.

Percutaneous mitral valvotomy using Inoue and double balloon technique: comparison of clinical and hemodynamic short term results in 350 cases

The results of percutaneous mitral valvotomy (PMV) by double balloon (N = 230, Group I) and Inoue single balloon (N = 120, Group II) technique were compared. The groups were similar with respect to baseline characteristics. Following PMV there were marked symptomatic and haemodynamic benefits in both the groups. There was significant increase in mitral valve area (MVA) estimated by Gorlin's equation (Group I: from 0.83 +/- 0.18 cm2 to 2.10 +/- 0.45 cm2, p < 0.001; Group II: from 0.83 +/- 0.17 cm2 to 2.16 +/- 0.39 cm2, p < 0.001) and by echoplanimetry (Group I: from 0.84 +/- 0.18 cm2 to 1.91 +/- 0.35 cm2, p < 0.001; Group II: from 0.88 +/- 0.17 cm2 to 1.96 +/- 0.30 cm2, p < 0.001). However, the percentage increase in MVA in the two groups by echoplanimetry (Group I: 136 +/- 59; Group II: 130 +/- 51; p = NS) and by Gorlin's equation (Group I: 164 +/- 69; Group II: 168 +/- 61; p = NS) were not statistically significant. Results were considered optimal when increase in MVA was > or = 1.5 cm2, percentage increase was > or = 50, and mitral regurgitation was < 2/4. Out of 216 patients in Group I where PMV could be performed, optimal results were achieved in 184 (85.2%) by Gorlin's equation and 178 (82.4%) by echoplanimetry. In Group II, out of 116 patients, optimal results were achieved in 107 (92.2%) by Gorlin's equation and 103 (89%) by echoplanimetry. Incidence of mitral regurgitation although higher in Group II (24.1% vs. 18.9%) was not statistically significant.(ABSTRACT TRUNCATED AT 250 WORDS)

Long-term echocardiographic evaluation of closed and open mitral valvulotomy

From 1968 to 1989, 280 patients with post-rheumatic pure mitral stenosis underwent surgical commissurotomy; 134 a closed and 146 an open technique. Follow-up exceeded 15 years in 56.7% of the patients. Echocardiographic analysis was performed in 120 patients and disclosed a larger mitral valve area in patients who underwent open valvulotomy (1.9 +/- 0.5 cm2 vs. 1.5 +/- 0.4 cm2 for the closed technique, P < 0.0002). On the other hand, considering the occurrence of post-surgical mitral regurgitation at a level greater than, or equal to moderate, open valvulotomy produced less favorable results (18.5% vs. 5% for the closed technique, P < 0.01).

Percutaneous transvenous mitral commissurotomy using the Inoue balloon catheter

Since its inception in 1982, percutaneous transvenous mitral commissurotomy (PTMC) with the Inoue balloon catheter has gained increasingly wide use internationally. The procedure is technically successful in over 90% of patients, and the long-term durability of commissurotomy is excellent in those with pliable mitral valve leaflets and minimally deformed submitral apparatus. PTMC offers an alternative to patients previously not considered candidates for surgery, where no alternative had existed in the past. After transseptal puncture, PTMC using the Inoue balloon can be accomplished easily in the majority of patients. In comparison to double balloon mitral valvotomy, the postdilatation valve area is similar, the incidence of mitral regurgitation is not different, and the fluoroscopic and procedure time are markedly shorter. While patients with little valve deformity are excellent candidates for this procedure, and those not considered candidates for surgical therapy are also easily defined, selection of patients for balloon dilatation among those with significant valve deformity who are otherwise candidates for valve replacement therapy remains a challenging problem.

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.

Predictors, mechanisms and outcome of severe mitral regurgitation complicating percutaneous mitral valvotomy with the Inoue balloon

During 241 consecutive percutaneous mitral valvotomy (PMV) procedures performed with the Inoue balloon, 16 patients (6.6%) developed severe mitral regurgitation (MR). Baseline clinical, echocardiographic (Doppler mitral valve area and Wilkins' score) and hemodynamic data were not different from those of patients without this complication. Severe MR occurred during the first inflation in 7 patients and after several stepwise inflations in 9. Although maximal balloon size was similar in both groups, unusual indentations and subvalvular inflations were more frequently observed in patients who developed severe MR. Early mitral valve replacement was required in 6 patients. All of them had a leaflet rupture either along the midportion (2 patients), along a commissure (4 patients), or both. Commissural calcium was present in 5 valves and 5 also had severe subvalvular involvement that had been underestimated by echocardiography. Of the 10 nonsurgically treated patients, 4 had chordal rupture by echocardiographic criteria, whereas in the remaining 6 the precise mechanism of MR could not be determined. During follow-up (11.4 +/- 4 months, range 1 to 30), 1 patient required surgery for symptoms and the remaining 9 were symptomatically improved and free of left ventricular dilatation. In conclusion, severe MR complicated 6.6% of PMV procedures with the Inoue balloon, and its mechanism was leaflet or chordal rupture. Although one third of the patients required early mitral surgery, most of the remaining obtained midterm symptomatic benefit.

Immediate effects of percutaneous transvenous mitral commissurotomy on pulmonary hemodynamics at rest and during exercise in mitral stenosis

Hemodynamics were evaluated during exercise in 33 patients with mitral stenosis who underwent percutaneous transvenous mitral commissurotomy (PTMC). PTMC was performed using an Inoue balloon. Each patient underwent a supine ergometer exercise test before and on the day after PTMC. Ergometer work load was started at 20 W and increased in increments of 20 W at 3-minute intervals until terminated by the patient's fatigue or shortness of breath. Mitral valve area increased by 0.8 +/- 0.4 cm2 (1.1 +/- 0.3 to 1.9 +/- 0.4 cm2, p less than 0.001). Mean mitral pressure gradient decreased (12 +/- 5 to 6 +/- 2 mm Hg, p less than 0.001). Pulmonary arterial pressure significantly decreased and the cardiac index significantly increased both at rest and during exercise after PTMC. Before PTMC, the increases in pulmonary arterial pressure, total pulmonary resistance and pulmonary arteriolar resistance during exercise were greater in patients with a mitral valve area less than 1.0 cm2 than in patients with an area greater than or equal to 1.0 cm2. After PTMC, total pulmonary resistance still increased during exercise. However, pulmonary arteriolar resistance did not change during exercise in patients with a mitral valve area greater than or equal to 1.5 cm2, whereas it increased in patients with an area less than 1.5 cm2. An enlarged mitral valve area greater than or equal to 1.5 cm2, which may prevent pulmonary vasoconstriction and permits a greater increase in pulmonary blood flow during exercise, is considered a good result immediately after PTMC.

Atrial septal puncture technique in percutaneous transvenous mitral commissurotomy: mitral valvuloplasty using the Inoue balloon catheter technique

Transseptal catheterization is a vital component of percutaneous transvenous mitral commissurotomy. Therefore, a well-executed transseptal catheterization is the key to a safe and successful percutaneous transvenous mitral commissurotomy. Two major problems inherent in atrial septal puncture for percutaneous transvenous mitral commissurotomy are cardiac perforation and puncture of an inappropriate atrial septal site. The former may lead to serious complication of cardiac tamponade and the latter to possible difficulty in maneuvering the Inoue balloon catheter across the mitral orifice. This article details atrial septal puncture technique, including landmark selection for optimal septal puncture sites, avoidance of inappropriate puncture sites, and step-by-step description of atrial septal puncture.

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)

Comparison of results of percutaneous mitral valvuloplasty in patients with large (greater than 6 cm) versus those with smaller left atria

To determine whether the presence of an aneurysmatic (severely enlarged) left atrium (greater than 60 mm on echocardiography) influences results of percutaneous mitral valvuloplasty (PMV), the clinical, echocardiographic and hemodynamic characteristics and the results of this technique were compared in 46 consecutive patients with aneurysmatic left atrium (group I) and 125 consecutive patients without such echocardiographic finding (group II). Left atrial size was 70.5 +/- 8 vs 50.1 +/- 6 mm (p less than 0.005) in groups I and II, respectively. Patients in group I were older (57 +/- 12 vs 48 +/- 12 years, p less than 0.025), more symptomatic (New York Heart Association functional class greater than or equal to III or IV: 67 vs 42%, p less than 0.05), and had atrial fibrillation more frequently (91 vs 44%, p less than 0.001). The echocardiographic score (8.9 +/- 1.9 vs 7.5 +/- 2, p less than 0.005) and the incidence of mild mitral regurgitation on angiography before PMV (54 vs 30%, p less than 0.01) was also higher in group I patients. Hemodynamic parameters before PMV were similar in both groups, but after the procedure, final mitral valve area (1.61 +/- 0.5 vs 1.95 +/- 0.4 cm2, p less than 0.05) and the absolute increase in mitral area (0.81 +/- 0.3 vs 1.02 +/- 0.3 cm2, p less than 0.05) were lower and mean pulmonary artery pressure (35 +/- 10 vs 28 +/- 9 mm Hg, p less than 0.025) was higher in group I.(ABSTRACT TRUNCATED AT 250 WORDS)

Effect of valve deformity on results and mitral regurgitation after Inoue balloon commissurotomy

BACKGROUND

The effect of valve deformity and patient age adversely affect the results of percutaneous transvenous mitral commissurotomy (PTMC) with conventional balloons.

METHODS AND RESULTS

These factors were characterized after PTMC with the Inoue balloon. The increases in mitral valve area and mitral regurgitation after the procedure were evaluated comparing echocardiographic score of 8 or less versus more than 8, age of less than 60 versus age of 60 years or more, and age of less than 70 versus age of 70 years or more. One hundred sixty-two patients (mean age, 52 +/- 14 years) were studied. For the entire group, mitral valve area increased from 1.0 to 1.8 cm2 (p less than 0.001). Valve area increased from 1.0 +/- 0.3 to 1.8 +/- 0.6 cm2 in patients with echocardiographic score of 8 or less (n = 102) and from 1.0 +/- 0.3 to 1.7 +/- 0.5 cm2 with echocardiographic score of more than 8 (n = 44). Patients less than 60 years old (n = 104) had increases in valve area from 1.0 +/- 0.3 to 1.8 +/- 0.6 cm2 versus 1.0 +/- 0.4 to 1.8 +/- 0.6 cm2 for those 60 years old or older (n = 50) (p = NS). There was no significant difference in resultant valve area when the age division was increased to less than 70 versus 70 years or more. Similarly, the percentage of patients with 2+ or greater increase in mitral regurgitation was not different for those with higher than for those with lower echocardiographic scores (4% versus 12%, p = NS), age of less than 60 versus age of 60 years or more (10% versus 10%, p = NS), or age of less than 70 versus age of 70 or more years (9% versus 18%, p = NS). Valve replacement for mitral regurgitation was performed in four patients (one emergency), all with echocardiographic scores of less than 8.

CONCLUSIONS

Age and extent of valve deformity do not have significant effects on acute results of PTMC using the Inoue balloon. Unique balloon geometry or the controlled, stepwise balloon sizing may explain these acceptable acute results in patients with more-deformed valves.