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Biomedical subjects

M Khalilullah

Publications and source records attributed to M Khalilullah.

At least 19 recordsLinked to original sources
PubMed1996

Balloon mitral commissurotomy: an intraoperative assessment.

OBJECTIVE: Advances in balloon catheter technology have revolutionized the management of obstructive cardiovascular diseases. For lesions like mitral stenosis, balloon commissurotomy has emerged as an alternative to surgical relief showing definite functional benefits in a few clinical trials, albeit with variable results. Such variability necessitated objective evaluation of the efficacy of balloon mitral commissurotomy. METHODS: The balloon mitral commissurotomy was carried out in 11 patients suffering from isolated mitral stenosis, under vision in a surgical setting. All patients were in NYHA class III/IV. Initially single balloon was used for mitral commissurotomy followed by double balloon, before completing the mitral valvotomy with surgical instruments whenever required. The commissural split was measured by firmly stretching the two commissures using nerve hooks and measuring the distance between the two hooks with the help of a caliper. Assessment of balloon dilation was made by calculating exact percentage of residual commissural split following balloon dilation as compared with completed mitral valvotomy. The exact percentage of commissural split was thus obtained by subtracting residual commissural split following balloon dilation from commissural split obtained after surgical open mitral valvotomy. RESULTS: Complete commissurotomy using the balloon technique was possible in two (18.2%) patients. In the remaining nine (81.8%) patients, balloon expansion provided only 50% to 80% of commissural split and required instrumental completion with good results. CONCLUSIONS: Balloon mitral commissurotomy, by virtue of its circumferential force, helps to develop a good cleavage and attains good hemodynamic improvement which may be life saving in critical mitral stenosis in selected group of patients with pliable mitral leaflets and minimal subvalvular pathology.

Adolescent↗
PubMed1994

Improved Doppler assessment of the Bjork-Shiley mitral prosthesis using the continuity equation.

To assess whether derivation of an effective mitral prosthetic valve area using the continuity equation provides an improved functional assessment of the Bjork-Shiley mitral prosthesis over the pressure half-time method, Doppler echocardiographic studies were performed in 43 patients 12 +/- 7 months following the valve replacement. Effective valve orifice area used as the standard for comparison was determined by a hydraulic formula validated in vitro over a wide range of flow rates. All patients were clinically stable, without evidence of prosthetic dysfunction or aortic regurgitation. Prosthetic mitral valve orifice area determined by the hydraulic formula, by the continuity equation and by pressure half-time method for all prostheses sizes averaged 1.6 +/- 0.46 cm2, 1.83 +/- 0.56 cm2 and 2.34 +/- 0.48 cm2, respectively. Effective valve orifice area by the hydraulic formula had a strong correlation with that derived by the continuity equation (r = 0.86; P < 0.0001; standard error of estimate (S.E.E.), 0.12 cm2), but an insignificant correlation with the area calculated by the pressure half-time method (r = 0.24). Prosthetic mitral valve areas determined by the continuity equation and by pressure half-time method also correlated poorly (r = 0.24). Pressure half-time was affected by heart rate, diastolic filling period, left ventricular fractional shortening and presence of atrial fibrillation (P < 0.001). Thus, using the standard continuity equation to determine the orifice area of the Bjork-Shiley prosthesis in the mitral position provides improved assessment compared with the pressure half-time method.

Adolescent↗
PubMed1994

International experience with secundum atrial septal defect occlusion by the buttoned device.

Several devices are available for transcatheter occlusion of atrial septal defect. This report describes the international experience with the buttoned device. During a 4.5-year period ending in February 1993, 180 transcatheter atrial septal defect occlusions were performed with the buttoned device. Patient age varied between 0.6 and 76 years and stretched atrial defect diameter between 5 and 25 mm. The defects were closed with 25 to 50 mm devices delivered through 8F (148 patients) or 9F (32 patients) sheaths. Twelve patients were adults whose defects were closed to prevent recurrence of cerebrovascular accidents caused by presumed paradoxic embolism. In the remaining patients the atrial defect was closed to treat the left-to-right shunt. The atrial septal defects were effectively occluded as demonstrated by (1) decrease in pulmonary-to-systemic flow ratio from 2.1 +/- 0.6 (mean +/- SD) to 1.05 +/- 0.1 (p < 0.01) by oximetry; (2) normalized S2 and disappearance of the diastolic murmur by auscultation; and (3) improvement in right ventricular volume overloading by echocardiogram. However, trivial to small shunts could be detected by color Doppler studies in 76 (45%) of 168 patients in whom such data are available. Complications included unbuttoning in 13 and whole-device embolization in 1. All patients remained stable, and retrieval of the device and surgical closure of the atrial septal defect were accomplished in 10 patients. Transcatheter retrieval was used in the remaining 4 patients. The incidence of unbuttoning, a major complication of the procedure, appeared to decrease with the increasing experience of the investigators and with device modification (third-generation). The follow-up duration varied between 1 month and 4 years. Six patients required surgery during the follow-up period. In the remaining patients (n = 160), clinical examination did not reveal signs of atrial shunts. Color Doppler studies revealed either complete disappearance of the previously demonstrated shunts or further diminution of their size. The results indicate that transcatheter occlusion of the atrial septal defects with buttoned devices is feasible, relatively safe, and effective, and it appears to be a viable alternative to surgery for some patients with secundum atrial septal defect. Complications are infrequent and should improve with experience.

Cardiac Catheterization↗
PubMed1994

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.

Adolescent↗
PubMed1993

Immediate and long-term results of balloon and surgical closed mitral valvotomy: a randomized comparative study.

Balloon mitral valvotomy (BMV) constitutes an important alternative to surgical closed mitral valvotomy (CMV) for the treatment of rheumatic mitral stenosis. To compare the immediate and long-term results of these procedures, 200 patients with rheumatic mitral stenosis were randomly assigned to undergo either BMV (n = 100) or CMV (n = 100). The age range was 10 to 30 (mean 19.4 +/- 6.5) years. Both procedures resulted in significant and similar increases in mitral valve area (BMV: 0.85 +/- 0.26 to 2.39 +/- 0.94 cm2; CMV: 0.79 +/- 0.21 to 2.2 +/- 0.85 cm2; p = NS). Mitral regurgitation developed in 14 patients after BMV and in 12 patients after CMV. Eighty patients in each group have now been followed for a mean period of 22 +/- 6.3 (range 6 to 38) months by repeat echocardiographic study. Restenosis (defined as a loss of more than 50% of the achieved increase in mitral valve area) was seen in four (5%) patients after BMV and in three (4%) after CMV. Symptomatic restenosis was seen in only one patient who at follow-up examination 20 months after CMV had a mitral valve area of 0.8 cm2 and underwent successful balloon valvotomy. We conclude that the immediate and long-term results obtained with percutaneous BMV and surgical closed mitral commissurotomy are comparable.

Adolescent↗
PubMed1993

Long-term results after balloon pulmonary valvuloplasty in adults.

Percutaneous balloon pulmonary valvuloplasty for congenital pulmonary valve stenosis was performed in 40 adult patients (aged 18 to 56 years). The duration of follow-up was 24.5 +/- 11.5 months. The peak systolic pressure gradient from the right ventricle to the pulmonary artery decreased from 107 +/- 29 mm Hg to 37 +/- 25 mm Hg immediately after the procedure. On follow-up, gradient obtained either by cardiac catheterization or Doppler echocardiography was 31 +/- 13 mm Hg. In eight patients with residual gradient after valvuloplasty of > 50 mm, the mean peak systolic gradient decreased from 74.5 +/- 18.3 to 33.5 +/- 13.9 mm Hg on follow-up. Thus balloon pulmonary valvuloplasty is a safe and effective procedure for the treatment of adult patients with pulmonic stenosis; there is a tendency for high residual gradients to regress on follow-up.

Adolescent↗
PubMed1993

Balloon angioplasty for renovascular hypertension in Takayasu's arteritis.

Percutaneous transluminal renal angioplasty was performed in 54 consecutive patients with hypertension and renal artery stenosis caused by Takayasu's arteritis. Angioplasty was technically successful in 67 (89.3%) of 75 lesions attempted. In these 67 lesions, the degree of stenosis decreased from 88.3 +/- 4.8% to 23.5% +/- 13.6% (p < 0.001) after angioplasty. Following successful angioplasty there was significant improvement in hypertension (p < 0.001) within 48 hours. Patients with bilateral renal artery stenosis had higher systolic blood pressure both before balloon dilatation (p < 0.05) and after balloon dilatation before discharge (p < 0.001), compared with patients with unilateral renal artery stenosis. Three to 70 months (mean 26.4 +/- 10.3 months) after successful angioplasty, blood pressure was reduced to normal or was improved in 93% of patients. Angiographic restudy an average of 14.2 +/- 7.8 months after angioplasty showed restenosis at the same site in 7 of 52 (13.5%) lesions and fresh stenosis in one artery. All these eight lesions were successfully dilated. Further improvement in the luminal diameter was observed in 11 (21.2%) lesions. Late angiographic restudy in seven patients an average of 56.1 +/- 6.3 months after angioplasty showed no restenosis. Our results suggest that balloon angioplasty is safe and highly effective in relieving renal artery stenosis caused by Takayasu's arteritis and should be the treatment of choice for renovascular hypertension in this disease.

Adolescent↗
PubMed1993

Atrial septal defect after balloon mitral valvuloplasty: a transesophageal echocardiographic study.

Fifty patients with rheumatic mitral stenosis aged twelve to thirty-six (twenty +/- six) years were studied by two-dimensional, pulsed and color Doppler echocardiography during, seventy-two hours after, and biweekly for three months after balloon mitral valvuloplasty (BMV). Transesophageal echocardiography (TEE) done immediately after BMV (in the catheterization laboratory) detected a new atrial septal defect (ASD) in 46 (92%) patients. These measured 1 to 2 (mean 1.2 +/- 0.3) mm in diameter. Doppler color flow mapping guided the location of the ASD in most of the cases. A narrow jet of left-to-right shunt could be evaluated by pulsed Doppler studies. Velocity time integral (VTI) of the jet across one cardiac cycle and the diameter of the ASD were used to calculate the left-to-right shunt (shunt = VTI x pi (D/2)2 x heart rate). The estimated shunt was 0.04-0.39 (mean 0.20 +/- 0.10) L/minute. A repeat study at seventy-two hours revealed the defect in 40 (80%) patients. At three months, the defect persisted in only 5 (10%) cases. The mean interval of closure of ASD was 4.6 +/- 2.2 weeks. The authors conclude: (1) ASD occurs commonly after BMV, (2) the septal defect and the resultant left-to-right shunt are insignificant, and (3) ASD disappears in the majority of cases by three months after BMV.

Adolescent↗
PubMed1992

Pulmonary venous flow dynamics before and after balloon mitral valvuloplasty as determined by transesophageal Doppler echocardiography.

The pattern of left atrial filling was studied in 14 patients with severe mitral stenosis in sinus rhythm before and immediately after successful balloon mitral valvuloplasty by transesophageal pulsed Doppler echocardiography of the left superior pulmonary vein. Mean mitral valve orifice area increased from 0.8 +/- 0.1 to 2.2 +/- 0.3 cm2 (p less than 0.0001), and left atrial mean pressure decreased from 30 +/- 5 to 12 +/- 4 mm Hg (p less than 0.0001) after the procedure. After balloon mitral valvuloplasty, significant increases in peak systolic pulmonary velocity (35 +/- 16 to 44 +/- 10 cm/s; p less than 0.01), systolic flow velocity time integral (3.3 +/- 1.5 to 5.9 +/- 2.0 cm; p less than 0.001) and the ratio of systolic/diastolic pulmonary venous flow velocity time integrals (0.8 +/- 0.4 to 1.4 +/- 0.5; p less than 0.001) were observed. An acute increase in mitral valve orifice area caused no significant changes in peak diastolic forward flow velocity (40 +/- 7 to 41 +/- 9 cm/s; p = not significant [NS]), diastolic forward flow velocity time integral (4.3 +/- 1.7 to 4.6 +/- 1.8 cm; p = NS) and atrial flow reversal velocity (30 +/- 3 to 35 +/- 3 cm/s; p = NS) compared with at baseline. The results suggest that in patients with severe mitral stenosis and sinus rhythm, left atrial filling is biphasic with a diastolic preponderance, and successful mitral valvuloplasty is associated with an immediate increase in pulmonary venous systolic forward flow.

Adult↗
PubMed1992

Percutaneous transluminal angioplasty in Takayasu arteritis.

Percutaneous transluminal balloon angioplasty (PTBA) was performed in 87 patients for 111 stenotic lesions due to Takayasu arteritis. Of the lesions attempted for dilatation, 35 were in the aorta, 64 in renal arteries, 9 in subclavian, and 3 in common iliac arteries. The stenosis of aorta could be successfully dilated in 33 of 35 (94.3%) patients with fall in peak systolic pressure gradient (PSG) from 77.7 +/- 28.4 mmHg to 26.4 +/- 20.6 mmHg (P < 0.001) and increase in luminal diameter from 4.7 +/- 2.4 mm to 10.1 +/- 4.1 mm (P < 0.001). On hemodynamic and angiographic restudy in 20 patients at 3-24 months (mean 7.7 +/- 4.1 months) further fall in PSG (> or = 15 mmHg) was observed in 7 patients, no significant change in 12 patients and restenosis with increase in PSG in one patient which could be successfully redilated. Late restudy at 36-60 months (mean 43 +/- 9.4) in six patients showed continued relief of stenosis (mean PSG 8.8 +/- 7.8 mmHg). Of the 64 stenotic lesions of the renal arteries, 58 (90.6%) could be successfully dilated with decrease in stenosis from 89.1 +/- 10.1% to 29.9 +/- 14.9% (P < 0.001). Follow-up intra-arterial digital subtraction angiography in 25 patients at a mean follow-up period of 13.1 months (range 3-29 months) showed restenosis in 5/36 (13.9%) lesions which could be successfully redilated. Angioplasty was also successful in dilating 8/9 (88.9%) subclavian and all 3 common iliac artery stenosis.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1992

Balloon angioplasty of native coarctation of the aorta in adolescents and young adults.

Balloon angioplasty of native coarctation of the aorta was performed in 35 consecutive adolescents and young adults, aged 14 to 37 years (mean 22.6 +/- 7.1). Twenty-eight (80%) patients had isolated discrete coarctation, six (17.1%) had tubular hypoplasia of the aortic isthmus, and one (2.9%) had hypoplasia of the post-coarctation aorta. The peak systolic pressure gradient decreased from 78.5 +/- 23.9 to 15.7 +/- 11.6 mm Hg (p less than 0.001), and the mean coarctation diameter increased from 4.7 +/- 2.4 to 13.1 +/- 2.7 mm (p less than 0.001) immediately after angioplasty. Patients with discrete-type coarctation had significantly less residual gradient than patients with long-segment tubular coarctation (12.3 +/- 10.7 vs 27.2 +/- 6.6 mm Hg, p less than 0.01). On recatheterization and angiography in 26 patients at 12.6 +/- 1.5 months after dilatation, there was no significant change in gradient (15.5 +/- 13.3 mm Hg) and diameter (13.1 +/- 1.8 mm) from the immediate post-angioplasty results. However, two patients had an increase in gradient and three had small aortic aneurysms with no change in appearance on restudy after 2 years. After 3 to 67 months' (mean 32.7 +/- 19.2) follow-up, all patients showed continued clinical improvement. Hypertension was relieved in 37.5% (12/32) and improved in 59.4% (19/32). Our experience suggests that balloon angioplasty of native aortic coarctation in adolescents and young adults is safe and highly effective with sustained improvement on intermediate-term follow-up.

Adolescent↗
PubMed1992

Balloon angioplasty of the aorta in Takayasu's arteritis: initial and long-term results.

Percutaneous transluminal balloon angioplasty for stenosis of the aorta was performed in 36 patients with Takayasu's arteritis (age range, 8 to 36 years; mean, 19.1 +/- 7.7 years). Balloon dilatation was successful in 34 patients and resulted in a decrease in the mean peak systolic pressure gradient (PSG) from 75.2 +/- 29.1 mm Hg to 24.8 +/- 19 mm Hg (p less than 0.001) and a mean increase in the diameter of the stenosed segments from 4.5 +/- 2.2 mm to 9.6 +/- 3.8 mm (p less than 0.001). Hemodynamic and angiographic restudy, which was performed in 20 patients at a mean follow-up period of 7.7 +/- 4.1 months (range, 3 to 24 months), showed a further decrease in PSG (greater than or equal to 15 mm Hg) in seven patients (from 40.0 +/- 11.2 mm Hg to 15.7 +/- 10.2 mm Hg; p less than 0.01), no significant change in PSG in 12 patients (17.1 +/- 13.6 mm Hg vs 16.6 +/- 12.7 mm Hg; p = NS), and an increase in PSG from 15 mm Hg to 85 mm Hg in one patient. The patient who showed restenosis underwent successful redilatation. Six patients who underwent late recatheterization and angiography at 36 to 60 months (mean, 43 +/- 9.4 months) show continued relief of stenosis (mean PSG, 8.8 +/- 7.8 mm Hg). Patients with short-segment (less than 4 cm) stenosis experience more relief than patients with long-segment (greater than or equal to 4 cm) stenosis (residual PSG, 18.6 +/- 8.2 mm Hg vs 40 +/- 16 mm Hg; p less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1992

Can mitral regurgitation after balloon dilatation of the mitral valve be predicted?

OBJECTIVE: To determine which factors predict the occurrence of mitral regurgitation after balloon dilatation of the mitral valve for rheumatic stenosis. DESIGN: Analysis of a case series of patients with rheumatic mitral valve stenosis who had had successful balloon dilatation of the mitral valve. SETTING: A tertiary care centre with an experience of over 150 balloon dilatations of the mitral valve. PATIENTS: 70 young patients with non-calcified rheumatic mitral stenosis, who had undergone successful balloon dilatation of the mitral valve. No patient had mitral regurgitation or atrial fibrillation before dilatation. INTERVENTION: Dilatation of the mitral valve by the transvenous, transatrial double balloon technique. MAIN OUTCOME MEASURE: Development of mitral regurgitation after balloon dilatation of the mitral valve and its relation to age, mitral valve area before dilatation and after dilatation, the degree of mitral subvalvar pathology, and the size of balloon used for dilatation. RESULTS: In 10 patients (14%) mitral regurgitation developed after balloon dilatation of the mitral valve. No statistically significant differences were found between patients who did not develop regurgitation and those who did in terms of age (mean (SD)) (19.9 (6.46) v 19.4 (5.5)), mitral valve area before dilatation (1.05 (0.33) v 0.94 (0.4) cm2) and after dilatation (2.52 (1.06) v 2.45 (1.1) cm2), mitral subvalvar pathology assessed by the mitral subvalvar distance ratio (0.116 (0.03) v 0.118 (2.32), or balloon diameter corrected for body surface area (21.37 (3.5) v 20.57 (2.32) mm/m2. CONCLUSIONS: In this subset of children and young adults with non-calcified mitral stenosis, none of the morphological, technical, or patient characteristics studied predicted the development of mitral regurgitation after balloon dilatation. The low incidence of mitral regurgitation may have reduced the discriminatory power of this study. None the less, the means and standard deviation for each factor in each group suggest that even in a larger sample size the variables would have little predictive capacity.

Adolescent↗
PubMed1991

Right atrial thrombus over eustachian valve--successful lysis with streptokinase.

Patients with pulmonary thromboembolism have occasionally been seen to have thrombi in the right atrium, either free floating or attached by a narrow pedicle. An echocardiographic description of a thrombus attached to the eustachian valve has, however, never been made in the literature. One such case is described in which streptokinase successfully lysed the thrombus.

Child↗
PubMed1991

Peripartum cardiomyopathy: prognostic variables at initial evaluation.

Twenty patients with peripartum cardiomyopathy were followed up for a period ranging from 6-14 months (mean 6 +/- 2 months). At initial evaluation, 16 patients were in New York Heart Association Class IV and the remainder in Class III. During follow up, 12 patients improved to Class I, 7 patients either failed to improve or deteriorated and one patient died. Certain variables at initial evaluation were related to prognosis. The patients who deteriorated, as compared to those who improved, were significantly older (30 +/- 6.8 vs 24 +/- 3 years, P less than 0.01), of higher parity (3 +/- 1 pregnancies vs 1.5 +/- 5 pregnancies, P less than 0.001) and had later onset of symptoms after delivery (7.6 +/- 4 weeks vs 3 +/- 1.3 weeks, P less than 0.001). They also had higher echocardiographic left ventricular end diastolic dimensions (7.0 +/- 8.4 cm vs 3.0 +/- 0.8 cm, P less than 0.001) and higher mean pulmonary arterial (38 +/- 4 mmHg vs 28 +/- 6 mmHg, P less than 0.001) and pulmonary arterial wedge pressures (24 +/- 2 mmHg vs 20 +/- 2 mmHg, P less than 0.001) at cardiac catheterization. Conduction defects were present on the surface electrocardiogram in all the patients who deteriorated, as compared to 4 patients who improved. In conclusion, certain variables at initial evaluation can help in identifying high risk subsets with peripartum cardiomyopathy.

Adult↗
PubMed1991

Assessment of mitral valvar stenosis by echocardiography: utility of various methods before and after mitral valvotomy.

Cross-sectional and Doppler echocardiography are currently the most important non-invasive tests for the evaluation of mitral stenosis. Recent experience has, however, shown that parameters that are reliable before mitral valvotomy may not be valid after the procedure. We have studied the validity of estimation of the area of the mitral valve by echo-planimetry, by Doppler pressure half time and the transmitral end-diastolic pressure gradient calculated by continuous wave Doppler in 100 patients (aged 10-30 years) before and after balloon mitral valvoplasty (n = 70) or surgical closed mitral valvotomy (n = 30). These patients underwent cardiac catheterisation and echocardiographic studies before, immediately after and 8-12 (9.3 +/- 2.2) weeks following balloon valvoplasty or closed valvotomy. The area as estimated echocardiographically correlated well with that obtained by the Gorlin formula before (r = 0.80), but not immediately after (r = 0.67) or on follow up after mitral valvotomy. There was good correlation between Doppler pressure half time and the area as estimated by the Gorlin formula before (r = 0.89) and on follow up after valvotomy (r = 0.82), but the correlation was not as good in the immediate period after valvotomy (r = 0.60). The end-diastolic pressure gradients obtained by Doppler examination and at cardiac catheterisation correlated well with each other before (r = 0.94), immediately after valvotomy (r = 0.92) and on follow up (r = 0.94). Hence, the reliability of estimation of the area of the mitral valve by echo-planimetry and by Doppler pressure half time varies according to the time at which the examination is performed following commissurotomy.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗