The ascending aorta in aortic stenosis.

Dilatation of the ascending aorta, a frequently reported sign of aortic stenosis, was assessed in 47 patients for whom aortic angiograms has been recorded. Twenty-eight of the patients had rheumatic valvar disease and 19 had congenital aortic stenosis. A simple ratio between the maximal width of the mid-ascending aorta and the width of the aortic root was calculated. Patients with congenital aortic stenosis had significantly greater supravalvar aortic dilatation than did those with rheumatic aortic valve involvement. There was no correlation between the pressure difference across the aortic valve and degree of dilatation of the ascending aorta.     

Balloon dilatation of the pulmonary valve. Short-, middle- and long-term results

BACKGROUND: Immediate and long-term results after balloon dilatation of pulmonary valve stenosis in our unit. METHODS AND PATIENTS: All 111 patients (1 day-18 years) who have had balloon dilatation of a pulmonary valvar stenosis between 12/1987 and 8/1997 were divided into 4 groups: Typical valvar pulmonary stenosis (group A; n = 78), stenosis with dysplastic pulmonary valve (group B; n = 10), critical pulmonary stenosis (group C; n = 16) and pulmonary atresia after transcatheter or operative opening of the valve (group D; n = 7). Patients with pulmonary stenosis and complex congenital heart disease were excluded. RESULTS: The average systolic transvalvular gradient was reduced from 68.5 to 27.2 mmHg (60%) immediately after balloon dilatation. After a follow up of 48.8 +/- 37 months 101 patients could be reevaluated. In group A (n = 69 at FU) and C (n = 16 at FU) 81% showed a systolic transvalvular gradient < 30 mmHg after one and 83% (A) respective 94% (C) after two balloon dilatations. In group B (n = 9 at FU) 44% exhibited a systolic gradient < 30 mmHg after one and 56% after two balloon dilatations. In group D (n = 7 at FU) 57% showed a systolic gradient < 30 mmHg with no further improvement by a second dilatation. Over all, 80% of our patients could be treated sufficiently by transcatheter means. The rate of major complications was 7.3% with no lasting residuals at follow up and no deaths. CONCLUSION: Balloon dilatation of the pulmonary valve is secure and effective. Best results are obtained in patients with typical pulmonary valve stenosis and in newborns and infants with critical pulmonary valve stenosis.     

Balloon dilatation of critical stenosis of the pulmonary valve in neonates.

Percutaneous balloon dilatation was attempted in 15 consecutive neonates (mean age 7.3 (range 1-27) days and weight 3.2 (range 2.5-4.1) kg) with critical stenosis of the pulmonary valve. Dilatation was successful in 11 (73%) patients. The mean balloon to annulus ratio was 1.1 (range 0.6-1.77). The ratio of right ventricle to femoral artery systolic pressure decreased from a mean (1 SD) of 1.4 (0.32) before to 0.8 (0.24) after dilatation and the transvalvar gradient decreased from 81 (29.7) mm Hg before to 33 (27.7) mm Hg after dilatation. All four (27%) patients in whom dilatation was unsuccessful underwent surgical valvotomy. Complications of balloon dilatation occurred in three (20%) patients; these included retroperitoneal haematoma (one) and iliofemoral venous occlusion (two). In one (7%) patient severe hypoxia and hypotension developed when the valve was crossed with a guide wire and balloon catheter. Despite successful dilatation he died 7 days after the procedure. During a mean (1 SD) follow up of 2 (1.7) years, seven (64%) of the 11 patients remained free of important restenosis. One patient required repeat dilatation three weeks after the initial procedure. In three (27%) patients restenosis developed 4-9 months after dilatation and all three had surgical valvotomy. Of the four patients initially referred for surgery three required a second operation and one required balloon dilatation. Percutaneous balloon dilatation gave effective relief of critical pulmonary stenosis in most neonates but complications and restenosis requiring surgery were common.     

Effect of age on valvular dysfunction and aortic dilatation in patients with a bicuspid aortic valve

Aortic regurgitation was the commonest functional anomaly among younger patients in a group of 63 individuals with a diagnosis of bicuspid aortic valve. With increasing age, a rise in the number with combined aortic valve disease and aortic stenosis was observed. Aortic dilatation was found in 65% of cases. Dilatation was independently associated with age and transvalvular aortic gradient.     

Echocardiographic assessment of the size of aortic and pulmonary valve annulus before balloon valvoplasty

Two dimensional echocardiographic measurements of the size of aortic and pulmonary valve annulus were made in 60 patients before balloon valvoplasty and compared to the angiographic measurements. Aortic valve annulus was measured in 34 patients (26 with valvar aortic stenosis and 8 with discrete subaortic stenosis) in the parasternal long axis or apical 5-chamber views. The pulmonary valve annulus was measured in 26 patients with valvar pulmonary stenosis (PS) in the parasternal short axis view of the right ventricular outflow view. The visualization of the annulus was good in all except 2 patients with valvar PS. Angiographic measurements of the aortic and pulmonary valve annulus were made in aortic root and right ventricular angiograms respectively, taken in both right and left anterior oblique views. There was an excellent correlation between the measurements of the annulus size by the two techniques (r value for pulmonary valve 0.91; for aortic valve 0.96; over all 0.94). Echocardiography can accurately measure valve annulus size and help in choosing balloon dilatation catheter of appropriate size before the valvoplasty procedure.     

Balloon dilatation of critical stenosis of the pulmonary valve in neonates

Percutaneous balloon dilatation was attempted in 15 consecutive neonates (mean age 7.3 (range 1-27) days and weight 3.2 (range 2.5-4.1) kg) with critical stenosis of the pulmonary valve. Dilatation was successful in 11 (73%) patients. The mean balloon to annulus ratio was 1.1 (range 0.6-1.77). The ratio of right ventricle to femoral artery systolic pressure decreased from a mean (1 SD) of 1.4 (0.32) before to 0.8 (0.24) after dilatation and the transvalvar gradient decreased from 81 (29.7) mm Hg before to 33 (27.7) mm Hg after dilatation. All four (27%) patients in whom dilatation was unsuccessful underwent surgical valvotomy. Complications of balloon dilatation occurred in three (20%) patients; these included retroperitoneal haematoma (one) and iliofemoral venous occlusion (two). In one (7%) patient severe hypoxia and hypotension developed when the valve was crossed with a guide wire and balloon catheter. Despite successful dilatation he died 7 days after the procedure. During a mean (1 SD) follow up of 2 (1.7) years, seven (64%) of the 11 patients remained free of important restenosis. One patient required repeat dilatation three weeks after the initial procedure. In three (27%) patients restenosis developed 4-9 months after dilatation and all three had surgical valvotomy. Of the four patients initially referred for surgery three required a second operation and one required balloon dilatation. Percutaneous balloon dilatation gave effective relief of critical pulmonary stenosis in most neonates but complications and restenosis requiring surgery were common.     

Aortic stenosis severity is not a risk factor for poststenotic dilatation of the ascending aorta.

BACKGROUND: Dilatation of the ascending aorta in aortic stenosis may be partly explained by intrinsic wall structure changes, but the relative contribution of altered hemodynamics is unclear. The aim of this study was to assess the association between ascending aortic dimensions and valve stenosis severity. METHODS AND RESULTS: An analysis of echocardiographic examinations was conducted in 296 patients with aortic stenosis (179 males, mean age 71 years), 57 with bicuspid and 239 with tricuspid aortic valve, mean transaortic gradient 43+/-20 mmHg, and not more than moderate aortic regurgitation. Aortic dimensions at the level of annulus, sinuses of Valsalva, sinotubular junction and proximal ascending aorta were measured. Only height (p<0.001), degree of aortic regurgitation (p<0.01) and presence of bicuspid aortic valve (p<0.001) were independent predictors of ascending aortic dimensions. CONCLUSIONS: An independent association between aortic pressure gradients and proximal ascending aortic dimensions was not observed in patients with bicuspid or tricuspid aortic valve stenosis. Therefore, the poststenotic dilatation of the ascending aorta is not explained by aortic stenosis severity itself. Possible nonhemodynamic causes deserve detailed study at the time of diagnosis.     

Balloon dilatation of the aortic valve: limited success and early restenosis.

Balloon dilatation of the aortic valve was attempted 16 times in 15 patients with severe aortic stenosis. None died but one had a transient stroke after the procedure. At dilatation the gradient across the aortic valve was reduced by greater than 30% in 69% of patients and the Gorlin valve area (calculated in 7/15 patients) increased by 30% in half. But a comparison of Doppler gradients measured before and one to two days after dilatation in 11 patients showed a greater than 30% reduction in the simultaneously measured gradient in only four. Doppler gradient was the most accurate predictor of symptomatic benefit and a fall in Doppler gradient persisted mainly in patients whose peak to peak gradient fell by at least 40% at the time of the procedure. Balloon dilatation of the aortic valve is a relatively safe procedure but it is less successful than previous reports suggest, perhaps because of early restenosis. Some forms of aortic stenosis may be more amenable to this procedure than others.     

Balloon dilatation of the aortic valve: limited success and early restenosis

Balloon dilatation of the aortic valve was attempted 16 times in 15 patients with severe aortic stenosis. None died but one had a transient stroke after the procedure. At dilatation the gradient across the aortic valve was reduced by greater than 30% in 69% of patients and the Gorlin valve area (calculated in 7/15 patients) increased by 30% in half. But a comparison of Doppler gradients measured before and one to two days after dilatation in 11 patients showed a greater than 30% reduction in the simultaneously measured gradient in only four. Doppler gradient was the most accurate predictor of symptomatic benefit and a fall in Doppler gradient persisted mainly in patients whose peak to peak gradient fell by at least 40% at the time of the procedure. Balloon dilatation of the aortic valve is a relatively safe procedure but it is less successful than previous reports suggest, perhaps because of early restenosis. Some forms of aortic stenosis may be more amenable to this procedure than others.     

Balloon dilatation of the aortic valve after previous surgical valvotomy: immediate and follow up results.

OBJECTIVE--To evaluate the immediate and long-term results of transcatheter balloon dilatation of the aortic valve for restenosis after previous surgical valvotomy. DESIGN--Prospective follow up by clinical examination and cross sectional Doppler echocardiography of all patients fulfilling the above criteria. SETTING--Tertiary paediatric cardiology referral centre. PATIENTS AND METHODS--22 patients (18 male, 4 female)--median (range) age 157.5 (12-254) months--underwent 25 balloon dilatation procedures at a median of 72 (8-155) months after surgery. The median age at surgical valvotomy was 82.5 (0.5-230) months and the systolic gradient across the aortic valve immediately after surgery was 31 (0-49) mm Hg. The indication for dilatation was a Doppler derived peak instantaneous gradient of > 60 mm Hg with grade 2 or less aortic regurgitation. A single balloon was used, and the median balloon to annulus ratio was 1 (0.9-1). RESULTS--After dilatation the catheter pullback gradient decreased acutely from 55 (35-75) to 30 (0-75) mm Hg (p < 0.01) and the Doppler gradient from 74 (52-92) to 40.5 (30-96) mm Hg (p < 0.01). In three patients who underwent a second dilatation of the aortic valve eight months after the first procedure, the pullback gradient decreased from 50 (50-60) to 15 (15-16) mm Hg. Aortic regurgitation grade increased from 1 (0-2) to 2 (1-3); only one patient had grade 3 regurgitation. Over a median follow up of 33 (2-67) months seven patients had aortic valve replacement for recurrent stenosis (six patients) or severe regurgitation (one patient with grade 3 regurgitation after dilatation, who had partial detachment of one of the valve leaflets). There was no significant difference for the pullback gradient (median of 19 v 32.5 mm Hg), Doppler gradient 24 hours after dilatation (33.5 v 50.5 mm Hg; p = 0.03), or the duration of follow up (27.5 v 18 months) between the 12 patients who did not require further dilatation or surgery and the 10 patients who did. CONCLUSIONS--Balloon dilatation of the aortic valve is a safe and feasible option for palliation of restenosis after surgical valvotomy for congenital aortic valve stenosis. In many patients, however, stenosis progressed and a further intervention was required.     

Aortic valve regurgitation and the congenitally bicuspid aortic valve: a clinico-pathological correlation.

OBJECTIVE--To investigate the morphology of congenitally bicuspid aortic valves causing pure valve regurgitation. DESIGN--A case series collected over five years. SETTING--An academic hospital. PATIENTS AND METHODS--One hundred and forty eight excised congenitally bicuspid aortic valves. The morphological findings were correlated with sex, age, clinical history, and data on haemodynamic function before operation. Pure valve regurgitation was defined as grade 3-4/4 with a gradient less than 30 mm Hg. Aortic root dilatation was evaluated angiographically or echocardiographically or both. RESULTS--Three types were recognised: valves that were purely bicuspid (23%), bicuspid valves with a raphe (34%), and valves with an additional indentation of the free edge of the conjoined cusp (43%). In 14 cases pure valve regurgitation was present. Dilatation of the aortic root was present in 47 cases. The relative risk for regurgitation when the aortic root was dilated (compared with no dilatation) was 3.99. The relative risk for valve regurgitation when there was indentation of the conjoined cusp (compared with no indentation) was 4.95. The mean age at operation in patients with pure regurgitation was 56 years, which is significantly younger (p = 0.0008) than that of patients with a congenitally bicuspid valve with combined valve stenosis and regurgitation (64.7 years). CONCLUSIONS--Congenitally bicuspid aortic valves with a central indentation of the free edge of the conjoined cusp seem particularly likely to develop pure aortic valve regurgitation.     

Balloon dilatation of the aortic valve in a pulsatile flow model: assessment of the mechanisms and the magnitude and duration of changes in valve area and gradient

Eighteen stenotic aortic valves (17 removed at operation) mounted in a pulsatile flow duplicator were dilated with a balloon catheter. Sequential measurements showed that the valve area initially increased from a mean (SD) of 0.52 (0.16) to 0.78 (0.17) cm2. It was 0.73 (0.16) cm2 five minutes after dilatation and this was little changed at four weeks (0.70 (0.15) cm2). Initially the mean transvalvar gradient fell significantly from 54 (27) to 32 (8) mm Hg but increased to 35 (10) mm Hg at five minutes and to 40 (11) mm Hg at four weeks. In six valves stretching of the orifice was the only mechanism responsible for the changes while in the remainder there was tearing through commissures with a greater initial increase in area (0.31 v 0.18 cm2) and a smaller decrease in area at five minutes (0.03 v 0.08 cm2). Fractures of calcific deposits in non-commissural positions were seen in one valve only. This laboratory study of isolated aortic valves showed a significant but small increase in valve area after balloon dilatation, which was greater when commissural tearing had occurred. Recoil of the stretched orifice was complete at five minutes and there was little further change over the next four weeks.     

Balloon dilatation of calcific aortic stenosis in elderly patients: postmortem, intraoperative, and percutaneous valvuloplasty studies

To assess the safety and efficacy of percutaneous balloon valvuloplasty in calcific aortic stenosis, balloon dilatation of critically stenosed, calcified aortic valves was performed in five postmortem hearts, in five patients intraoperatively before aortic valve replacement, and in two elderly patients percutaneously at the time of diagnostic catheterization. The etiology of aortic stenosis in the 12 cases was rheumatic in two, congenital bicuspid calcific stenosis in one, and senile calcific degenerative stenosis in the remaining nine. Prevalvuloplasty examination in the 10 postmortem and intraoperative cases revealed rigid valve leaflets with commissural fusion in three valves and extensive nodular calcification in seven. Subsequent balloon dilatation with 15 to 18 mm valvuloplasty balloons resulted in decreased cusp rigidity and increased mobility of valve leaflets in all cases, without evidence of tearing of valve leaflets, disruption of the valvular ring, or liberation of calcific or valvular debris. In the three valve specimens with commissural fusion, balloon dilatation resulted in partial or complete separation of leaflets along fused commissures. In two cases with extensive nodular calcification, balloon dilatation resulted in a fracture of a calcified leaflet that was evident on both gross and radiologic examination. After postmortem and intraoperative studies, percutaneous catheter valvuloplasty was performed at the time of diagnostic catheterization in two elderly patients (93- and 85-year-old women) with long-standing calcific aortic stenosis. Balloon dilatation with 12 to 18 mm balloons resulted in significant decreases in aortic gradients and significant increases in cardiac index and aortic valve area in both patients. Percutaneous valvuloplasty in both patients resulted in a mild increase in aortic insufficiency and no evidence of embolic phenomena.     

Transluminal balloon dilatation for discrete subaortic stenosis

Ten children, 10 weeks to 18 years old, with discrete subaortic stenosis (DSS) underwent transluminal balloon dilatation of the subaortic obstruction. The DSS was visualized by 2-dimensional echocardiography and cineangiography. Six patients had a thin discrete "membrane" immediately below the aortic valve (group I) and 4 patients had a thicker fibromuscular ring about 1 cm below the aortic valve (group II). In group I, the mean gradient decreased from 82 +/- 49 mm Hg (range 35 to 164) to 22 +/- 15 mm Hg (range 5 to 40); in group II, it decreased from 155 +/- 18 mm Hg (range 132 to 177) to 85 +/- 44 mm Hg (range 60 to 150). Three patients had follow-up cardiac catheterization 1 year later. Their mean gradient soon after the procedure was 37 +/- 23 mm Hg. On follow-up, it was still 37 +/- 19 mm Hg, indicating persistence of relief of the obstruction. Because of the high residual gradient in group II, 3 patients had surgical relief of the obstruction. The degree of aortic regurgitation present before the dilatation in all 10 patients did not change after the procedure. The mechanism of relief of the obstruction was by tearing of the subaortic membrane. Our data suggest that relief of subaortic obstruction is more favorable in the thin, membranous DSS.     

Percutaneous balloon dilatation of aortic valve stenosis in neonates and infants.

Percutaneous balloon dilatation of severe aortic valve stenosis was attempted in thirteen patients (seven neonates and six infants). In two the valve could not be crossed and both died during subsequent operation. Two patients died during manipulation of the balloon catheter. No significant benefit was obtained in another patient who later died during operation. Balloon dilatation was successful in the remaining eight patients, reducing the aortic valve pressure gradient from a mean of 63 mmHg (95% confidence interval 38 to 88 mmHg) to a mean of 23 mmHg (95% confidence interval 7 to 39 mmHg). Two of these patients subsequently died from heart failure related to other cardiac lesions. The six survivors have done well. At follow up the maximum Doppler velocities in the ascending aorta ranged from 1.9 to 4.0 m/s after 2-23 months, but despite this evidence of an increasing valve gradient there has been lasting clinical improvement.     

Balloon dilation of congenital aortic valve stenosis. Results and influence of technical and morphological features on outcome

We evaluated dilation technique (n = 80) and aortic valve morphology by two-dimensional echocardiography (n = 58) in patients with congenital aortic valve stenosis to determine their influence on outcome. Patients' age (9 +/- 9 years; range, 1 day-39 years) and a history of surgical valvotomy did not influence outcome. The number of dilating balloons (one vs. two) and balloon: annulus ratio based on the largest balloon used in each case (97 +/- 12%; range, 71-133%) did not demonstrably influence the percent reduction in valvar gradient. In contrast, with a balloon: annulus ratio greater than 100%, the incidence (26%) of significant, dilation-induced aortic regurgitation was higher than occurred when the ratio was equal to or less than 100% (11%). Fifty bicommissural and eight unicommissural valves were identified echocardiographically. Relief of obstruction was associated with apparent commissural division in 24 of 32 patients with suitable postdilation studies. The sites of fusion and stenosis relief did not influence percent reduction in valvar gradient. Substantial increases in aortic regurgitation (greater than three of five grades) occurred in three of eight unicommissural and one of 50 bicommissural valves. The presence of a thick valve was associated with a slightly lower gradient reduction (53 +/- 12%) than thin and pliant valves (63 +/- 24%) (p greater than 0.05). Unlike all other congenital lesions we have studied, dilation technique and balloon size appeared to have a lesser influence on percent reduction in valvar gradient in congenital aortic stenosis, although balloon: annulus ratio influences the increase in aortic regurgitation. Valve morphology appears to assist with predicting the outcome of dilation.     

Effects of increasing flow rate on aortic stenotic indices: evidence from percutaneous transvenous balloon dilatation of the mitral valve in patients with combined aortic and mitral stenosis.

OBJECTIVES: To investigate the effects of transvalvar flow rate on aortic valve resistance and valve area after percutaneous transvenous balloon dilatation of the mitral valve in a homogeneous group of patients with rheumatic heart disease. DESIGN: Retrospective analysis of 12 patients with combined aortic and mitral stenosis who had undergone balloon dilatation of the mitral valve over a period of 9 years. SETTING: Tertiary referral centre. PATIENTS: Twelve (8 women, 4 men; mean (SD) age 37 (9) of 227 consecutive patients with critical mitral stenosis undergoing transvenous balloon dilation of the mitral valve in the centre also had aortic stenosis, defined as a transaortic pressure gradient of more than 25 mm Hg measured at a catheterisation study before valvuloplasty. INTERVENTIONS: Echocardiographic variables (mitral valve area measured by the pressure half-time method and planimetry, and the aortic valve area derived from the continuity equation) and haemodynamic measurements (cardiac output, left ventricular mean systolic pressure, aortic mean pressure, transaortic valve pressure gradient, mitral valve and aortic valve areas derived from the Gorlin formula, and aortic valve resistance) were assessed before and after transvenous balloon dilatation of the mitral valve. Follow up catheterisation to measure haemodynamic variables was performed one week after mitral valvuloplasty. RESULTS: Mean transaortic flow rate increased 33% after mitral valvuloplasty (from 198 (68) to 254 (41) ml/s, P = 0.002). Aortic valve areas derived from the Gorlin formula were significantly increased from 0.57 (0.12) to 0.73 (0.14) cm2 (P = 0.006) after mitral valvuloplasty. However, aortic valve area and valve resistance derived from the continuity equation were independent of the increase in flow rate after mitral valvuloplasty (from 1.29 (0.35) to 1.30 (0.29) cm2 and from 317 (65) to 259 (75) dyn.s.cm-5, both P = NS). CONCLUSION: The Gorlin-derived aortic valve area tends to be flow-dependent, and continuity equation-derived aortic valve area and catheterisation-derived valve resistance seem to be less flow-dependent. In patients with combined mitral and aortic stenosis, these flow-independent indices are important for decision-making.     

The risk of having additional obstructive lesions in neonatal coarctation of the aorta

Infants with coarctation of the aorta may have obstructions at other sites within the left heart which are not always apparent on the initial echocardiogram. The magnitude of the risk of having the additional obstructions is not well described, with few reliable quantitative criterions for identifying patients at the highest risk. We determined the frequency of additional, late appearing, stenotic lesions within the left heart, and the predictive morphologic features on the initial cross-sectional echocardiogram. We identified all patients with coarctation of the aorta diagnosed by 3 months of age, excluding those with complex cardiac disease or definite additional stenotic lesions at presentation, leaving 101 patients for study. At follow-up, 31 stenotic lesions were diagnosed in 23 patients, 15 of whom had at least 1 intervention. Mitral stenosis was diagnosed in 11 patients, aortic stenosis in 10, subaortic stenosis in 8, and supravalvar aortic stenosis in 2. The probability for freedom from obstructive lesions was 81% at 1 year, 74% at 3 years, and 70% at 5 years. Echocardiographic predictors of mitral stenosis included smaller mitral valvar annuluses, presence of a mean transmitral gradient between 2.5 and 5.0 mmHg, and elongation of the area of intervalvar fibrous continuity. Predictors of aortic stenosis were smaller mitral valvar annuluses, an initial aortic valvar gradient between 15 and 20 mmHg, and obliteration of the commissure between the right and non-coronary leaflets of the aortic valve. Predictors of subaortic stenosis were smaller mitral valvar annuluses and elongation of the area of intervalvar fibrous continuity. Patients with Z-scores for the diameter of the mitral valve of less than -1 were at the highest risk for manifesting obstructive lesions at any level. Associated stenoses in the left heart are common in the setting of aortic coarctation. When Doppler data is equivocal, features of the cross-sectional echocardiogram can identify the sub-group of infants at increased risk.     

Aortic valve regurgitation and the congenitally bicuspid aortic valve: a clinico-pathological correlation.

OBJECTIVE--To investigate the morphology of congenitally bicuspid aortic valves causing pure valve regurgitation. DESIGN--A case series collected over five years. SETTING--An academic hospital. PATIENTS AND METHODS--One hundred and forty eight excised congenitally bicuspid aortic valves. The morphological findings were correlated with sex, age, clinical history, and data on haemodynamic function before operation. Pure valve regurgitation was defined as grade 3-4/4 with a gradient less than 30 mm Hg. Aortic root dilatation was evaluated angiographically or echocardiographically or both. RESULTS--Three types were recognised: valves that were purely bicuspid (23%), bicuspid valves with a raphe (34%), and valves with an additional indentation of the free edge of the conjoined cusp (43%). In 14 cases pure valve regurgitation was present. Dilatation of the aortic root was present in 47 cases. The relative risk for regurgitation when the aortic root was dilated (compared with no dilatation) was 3.99. The relative risk for valve regurgitation when there was indentation of the conjoined cusp (compared with no indentation) was 4.95. The mean age at operation in patients with pure regurgitation was 56 years, which is significantly younger (p = 0.0008) than that of patients with a congenitally bicuspid valve with combined valve stenosis and regurgitation (64.7 years). CONCLUSIONS--Congenitally bicuspid aortic valves with a central indentation of the free edge of the conjoined cusp seem particularly likely to develop pure aortic valve regurgitation.     

Echocardiographic restenosis after successful balloon dilatation of the mitral valve with the Inoue balloon: experience of a United Kingdom centre.

OBJECTIVES--(a) To assess the echocardiographic incidence of restenosis after successful balloon dilatation of the mitral valve at a mid-term follow up of one year among a population of predominantly United Kingdom patients. (b) To identify any factors, assessed before or during dilatation, which may predict the development of restenosis. DESIGN--Successful dilatation of the mitral valve was defined as an increase in mitral valve area of > 25% and a final valve area of at least 1.5 cm2. Echocardiographic restenosis was defined at follow up as a loss of 50% of initial gain and a valve area of less than 1.5 cm2. Mitral valve area was assessed by transthoracic echocardiography before, during, 48 hours after, and one year after successful balloon dilatation of the mitral valve. Echo score before dilatation (an assessment of valvar and subvalvar calcification, thickening, and mobility), age, rhythm, echocardiographic mitral valve area before and after dilatation, left atrial pressure before and after dilatation, and end diastolic mitral valve gradient before and after dilatation were compared in those patients with and without echocardiographic restenosis at one year. SETTING--A regional cardiothoracic centre in the United Kingdom that performs 20-30 balloon dilatations of mitral valves each year. PATIENTS--39 patients, with symptomatic dominant mitral stenosis, who had undergone successful balloon dilatation of the mitral valve, and in whom echocardiographic assessment of mitral valve area was available at one year. 92% of patients were citizens of the United Kingdom. INTERVENTIONS--Balloon dilatation of the mitral valve by the Inoue technique. MAIN OUTCOME MEASURES--Mitral valve area and patient symptom class (New York Heart Association) one year after successful dilatation of the mitral valve. RESULTS--The incidence of echocardiographic restenosis was eight of 39 patients (21%). Of the eight patients with restenosis four underwent mitral valve replacement, two had repeat dilatation of the mitral valve, and two remained on medical treatment. With univariant analysis, factors associated with restenosis were increased age, higher echo score before dilatation, and a lower mitral valve area immediately after the operation. The only independent risk factor for restenosis, shown by multivariant analysis, was a high echo score before dilatation. There was no significant fall in mitral valve area at one year in those patients without restenosis. Most (28/31) of these patients had echocardiographic evidence of splitting of at least one commissure after dilatation compared with only two of eight patients who developed restenosis. Of 10 patients with an echo score before dilatation > or = 10 only two had an initially successful operation and no restenosis at one year. CONCLUSIONS--The echocardiographic incidence of restenosis after dilatation of the mitral valve by the Inoue technique in patients of the United Kingdom is 21%. The principal factor associated with restenosis is a high echo score before dilatation. Increases in mitral valve area are maintained in those patients without restenosis and it is likely that the mechanism of initial increase in valve area is different in the two groups, being commissural splitting in those patients who do not get restenosis and valve stretching in those that do. In patients with an echo score > or = 10 dilatation of the mitral valve should be considered only as a palliative procedure.