Doppler evaluation of results of percutaneous aortic balloon valvuloplasty in calcific aortic stenosis

To evaluate the short-term results of percutaneous aortic balloon valvuloplasty, 55 consecutive elderly patients with symptomatic, severe aortic stenosis who were at high risk for surgical intervention underwent the procedure, with follow-up by clinical evaluation and Doppler echocardiography. Over a mean follow-up of 6.2 months, there were three early deaths (less than 30 days) and eight late deaths. Nine patients underwent subsequent aortic valve surgery, and four had repeat balloon valvuloplasty. Doppler echocardiography revealed a reduction in aortic valve mean gradient from 48 +/- 18 to 33 +/- 12 mm Hg after the procedure (p less than 0.0001) but a return to 46 +/- 16 mm Hg at follow-up (p less than 0.05). The aortic valve area increased from 0.54 +/- 0.15 to 0.85 +/- 0.23 cm2 after the procedure (p less than 0.0001), but there was a significant decrease to 0.67 +/- 0.19 cm2 at follow-up (p less than 0.05). Of patients free of aortic valve operation or death after 30 days after the procedure, 76% were severely symptomatic before the procedure as compared with 38% at follow-up. In patients undergoing percutaneous aortic balloon valvuloplasty, there is a continued high short-term mortality and a significant incidence of restenosis over short-term follow-up. Nonetheless, a subset of patients do experience sustained clinical improvement from this procedure.     

Serial evaluation of ventricular function after percutaneous aortic balloon valvuloplasty

To evaluate the serial changes in right and left ventricular performance after percutaneous aortic balloon valvuloplasty, 15 patients, mean age 75 +/- 18 years, and in New York Heart Association (NYHA) class III, were studied with first-pass radionuclide angiocardiography (RNA) immediately before, then 5 minutes, 2 hours, 4 hours, 6 hours, and 3 days after valvuloplasty. No change was observed in heart rate, aortic root systolic pressure, Fick, or RNA cardiac output, amount of aortic insufficiency measured either angiographically or with the regurgitant fraction determination immediately after valvuloplasty. However, significant changes were observed in the peak-to-peak aortic valve gradient (63 to 35 mm Hg; p less than 0.001), mean aortic valve gradient (54 to 33 mm Hg; p less than 0.001), aortic valve area (0.60 to 0.90 cm2; p less than 0.001), and meridional wall stress (79 to 50 10(3) dynes/cm2; p less than 0.01) immediately following valvuloplasty. In addition, left ventricular end-diastolic volume decreased from 186 to 153 ml (p less than 0.001), end-systolic volume decreased from 114 to 86 ml (p less than 0.001), micromanometric left ventricular end-diastolic pressure decreased from 20 to 14 mm Hg (p less than 0.02), and left ventricular ejection fraction increased from 0.39 to 0.45 (p less than 0.001). Peak positive left ventricular dP/dt and end-systolic pressure-volume ratio did not change after valvuloplasty (1700 to 1550 mm Hg/sec, 2.1 to 2.5 mm Hg/ml, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)     

Clinical and Doppler echocardiographic follow-up after percutaneous balloon valvuloplasty for aortic valve stenosis

Percutaneous balloon valvuloplasty has been shown to increase the aortic orifice area and to improve clinical symptoms. However, there are only few data concerning long-term results after balloon valvuloplasty. In this study, 36 patients (11 men, 25 women, mean age 75 +/- 8 years) were followed after balloon valvuloplasty for a period of up to 18 months by means of clinical parameters and repeated Doppler echocardiographic measurements after 1, 3, 6, 12 and 18 months. Invasive measurements revealed a decrease of the systolic peak gradient from 78 +/- 24 to 38 +/- 13 mm Hg (p less than 0.001), and an increase in the aortic orifice area from 0.58 +/- 0.23 to 0.93 +/- 0.2 cm2 (p less than 0.001). The Doppler echocardiographic approach revealed that the maximal instantaneous gradient decreased from 96 +/- 26 to 67 +/- 22 mm Hg (p less than 0.001). The aortic orifice area increased from 0.49 +/- 0.16 to 0.73 +/- 0.21 cm2 (p less than 0.001). Three patients (8%) died in the hospital. After hospital discharge, 16 patients (44%) died and 8 patients (22%) underwent successful aortic valve replacement after a mean follow-up of 8 +/- 6 months. Nine patients (25%) were alive after a follow-up period of 18 months. Seven of these (19%) remained clinically improved. During follow-up, the Doppler echocardiographic results revealed a continuous trend toward the preprocedural severity of the aortic valve stenosis. Progression of restenosis assessed by Doppler echocardiographic measurements was accelerated in the group of patients who subsequently died or underwent repeat balloon valvuloplasty or aortic valve replacement.     

Serial assessment of mitral regurgitation by pulsed Doppler echocardiography in patients undergoing balloon aortic valvuloplasty

Mitral regurgitation was serially assessed by pulsed Doppler echocardiography in 144 patients undergoing balloon aortic valvuloplasty for symptomatic aortic stenosis. Regurgitant scores of 0, 1, 2 and 3 were assigned to pulsed Doppler patterns corresponding to no, mild, moderate and severe mitral regurgitation, respectively. Before balloon aortic valvuloplasty, mitral regurgitant score correlated significantly (p less than 0.005) but weakly with aortic valve area (r = -0.24), left ventricular ejection fraction (r = -0.34) and left ventricular systolic pressure (r = 0.23). There was no significant correlation between mitral regurgitation and either mean catheterization or mean Doppler aortic valve gradient. Balloon aortic valvuloplasty produced significant decreases in both catheterization and Doppler mean transvalvular aortic valve gradients (56 +/- 19 to 31 +/- 12 and 60 +/- 19 to 48 +/- 16 mm Hg, respectively; both p less than 0.0001) and a significant increase (p less than 0.0001) in aortic valve area assessed by catheterization (0.6 +/- 0.2 to 0.9 +/- 0.3 cm2). Left ventricular ejection fraction did not change, but cardiac output increased (p less than 0.001) and pulmonary capillary wedge pressure decreased (p less than 0.0001). Pulsed Doppler findings of mitral regurgitation were present in 102 of the 144 patients. Eighty-eight patients had a score compatible with mild or more severe degrees of mitral regurgitation, and 49 had a score indicative of moderate or severe valvular insufficiency. In the entire group of 144 patients, mitral regurgitant score decreased significantly from 1.1 +/- 1.0 to 1.0 +/- 1.0 (p less than 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)     

Assessment of left ventricular and aortic valve function after aortic balloon valvuloplasty in adult patients with critical aortic stenosis

Preliminary reports have documented the utility of balloon aortic valvuloplasty as a palliative treatment for high-risk patients with critical aortic stenosis, but the effect of this procedure on cardiac performance has not been studied in detail. Accordingly, 32 patients (mean age 79 years) with long-standing, calcific aortic stenosis were treated at the time of cardiac catheterization with balloon dilatation of the aortic valve, and serial changes in left ventricular and valvular function were followed before and after valvuloplasty by radionuclide ventriculography, determination of systolic time intervals, and Doppler echocardiography. Prevalvuloplasty examination revealed heavily calcified aortic valves in all patients, a mean peak-to-peak aortic valve gradient of 77 +/- 27 mm Hg, a mean Fick cardiac output of 4.6 +/- 1.4 liters/min, and a mean calculated aortic valve area of 0.6 +/- 0.2 cm2. Subsequent balloon dilatation with 12 to 23 mm valvuloplasty balloons resulted in a fall in aortic valve gradient to 39 +/- 15 mm Hg, an increase in cardiac output to 5.2 +/- 1.8 liters/min, and an increase in calculated aortic valve area to 0.9 +/- 0.3 cm2. Individual hemodynamic responses varied considerably, with some patients showing major increases in valve area, while others demonstrated only small increases. In no case was balloon dilatation accompanied by evidence of embolic phenomena. Supravalvular aortography obtained in 13 patients demonstrated no or a mild (less than or equal to 1+) increase in aortic insufficiency. Serial radionuclide ventriculography in patients with a depressed left ventricular ejection fraction (i.e., that less than or equal to 55%) revealed a small increase in ejection fraction from 40 +/- 13% to 46 +/- 12% (p less than .03). In addition, for the study group as a whole there was a decrease in left ventricular end-diastolic volume index (113 +/- 38 to 101 +/- 37 ml/m2, p less than .003), a fall in stroke-volume ratio (1.49 +/- 0.44 to 1.35 +/- 0.33, p less than .04), and no immediate change in left ventricular peak filling rate (2.05 +/- 0.77 to 2.21 +/- 0.65 end-diastolic counts/sec, p = NS). Serial M mode echocardiography and phonocardiography showed an increase in aortic valve excursion (0.5 +/- 0.2 to 0.8 +/- 0.2 cm, p less than .001), a decrease in time to one-half carotid upstroke (80 +/- 30 to 60 +/- 10 msec, p less than .001), and a small decrease in left ventricular ejection time (0.44 +/- 0.03 to 0.42 +/- 0.02 sec, p less than .001).(ABSTRACT TRUNCATED AT 400 WORDS)     

Usefulness of noninvasive assessment of aortic stenosis before and after percutaneous aortic valvuloplasty

Noninvasive and catheterization studies were performed in 40 patients (mean age 76 +/- 12 years) before and after percutaneous aortic valvuloplasty. Measurements included time to 1/2 carotid upstroke, left ventricular ejection time, aortic valve excursion, mean aortic valve gradient and aortic valve area assessed using the continuity equation: aortic valve area = A X V/V1, where A = left ventricular outflow tract area, V = maximal left ventricular outflow tract velocity assessed by pulsed Doppler echocardiography and V1 = peak velocity in the aortic stenotic jet assessed using continuous-wave echocardiography. In addition, mitral regurgitation was assessed by pulsed Doppler mapping techniques. Mean aortic valve gradient, cardiac output and aortic valve area, calculated using the Gorlin formula, were determined at cardiac catheterization. There were significant correlations between Doppler and catheterization measurements of aortic valve area both before (r = 0.71, p less than 0.001) and after (r = 0.85, p less than 0.0001) valvuloplasty. The relations were demonstrated to be linear by F test and met criteria for identity. There were significant increases (all p less than 0.0005) after valvuloplasty in catheterization valve area (0.60 +/- 0.21 to 0.95 +/- 0.39 cm2), Doppler valve area (0.64 +/- 0.22 to 0.91 +/- 0.37 cm2), valve excursion (0.5 +/- 0.3 to 0.8 +/- 0.3 cm) and cardiac output (4.5 +/- 1.6 to 4.9 +/- 1.7 liter/min).(ABSTRACT TRUNCATED AT 250 WORDS)     

Methodologic issues in clinical evaluation of stenosis severity in adults undergoing aortic or mitral balloon valvuloplasty. The NHLBI Balloon Valvuloplasty Registry.

Although both catheterization and Doppler measures of valvular stenosis severity have been validated, each has specific advantages and limitations, particularly in the setting of balloon valvuloplasty. Invasive valve area and mean pressure gradient recorded immediately before and after aortic (n = 589) or mitral (n = 608) catheter balloon valvuloplasty were compared with Doppler valve area and mean pressure gradient recorded less than 30 days before and 24 to 72 hours after the procedure. For aortic stenosis, Doppler valve area ranged from 0.1 to 1.4 cm2 before and 0.2 to 2.3 cm2 after catheter balloon valvuloplasty. Doppler and invasive aortic valve areas differed by less than or equal to 0.5 cm2 in 99% and by less than 0.2 cm2 in 92% of patients. Linear correlation was higher before versus after catheter balloon valvuloplasty, for both valve area (r = 0.49 vs r = 0.35, p = 0.01) and mean pressure gradient (r = 0.64 vs r = 0.50, p = 0.01). Group mean invasive valve area was slightly smaller before (0.50 vs 0.59 cm2, p less than 0.0001) but was not different after (0.80 vs 0.78 cm2, p = 0.16) catheter balloon valvuloplasty. Variables affecting the valve area differences were cardiac output, aortic regurgitation, heart rate and blood pressure. Mean pressure gradient differences were related to echo quality, blood pressure and mitral regurgitation. For mitral stenosis, 2-dimensional echocardiographic valve area ranged from 0.4 to 2.8 cm2 before and 0.7 to 3.8 cm2 after catheter balloon valvuloplasty. Two-dimensional echocardiography and invasive mitral valve areas differed by less than or equal to 0.5 cm2 in 96% and by less than 0.2 cm2 in 81% of cases. Linear correlation was not different before versus after catheter balloon valvuloplasty for two-dimensional echocardiographic valve area (r = 0.40 vs 0.36), pressure halftime valve area (r = 0.31 vs 0.32) or mean pressure gradient (r = 0.55 vs r = 0.46). Group mean 2-dimensional echocardiography and pressure halftime valve areas were larger than invasive valve areas before (1.09 vs 1.02 cm2, p = 0.001) and smaller after (1.71 vs 2.02 cm2, p less than 0.0001) catheter balloon valvuloplasty. Important variables affecting the differences were mitral regurgitation, interatrial shunt, cardiac output and heart rate. Nonsimultaneous studies, differing volume flow measurements, and the underlying accuracy of each technique largely account for discrepancies between these methods. The clinical use of each will depend on its ability to predict long-term patient outcome.     

Short- and midterm results of balloon valvuloplasty for valvular aortic stenosis in children.

During a 27-month period, 21 consecutive children (aged 0.1 to 15.7 years) with isolated valvular aortic stenosis underwent percutaneous transfemoral balloon valvuloplasty. Ten children had undergone earlier surgical valvulotomy. The indication for treatment was ST-T-segment changes at rest or during bicycle-ergometry, a continuous-wave Doppler-derived transvalvular gradient greater than 60 mm Hg or syncope, or a combination. Mean peak systolic left ventricular pressure decreased from 165 +/- 19 to 131 +/- 19 mm Hg (p less than 0.001). Mean end-diastolic left ventricular pressure did not change significantly (12 +/- 3 vs 11 +/- 5 mm Hg). Mean peak systolic valve gradient decreased from 71 +/- 23 to 22 +/- 11 mm Hg (p less than 0.001). Mean cardiac index remained unchanged (2.9 +/- 0.8 vs. 3.0 +/- 0.7 liters.min-1.m-2). Aortic valve regurgitation on angiography appeared or increased in 9 patients (up to grade 3 in 3 children). Noninvasive follow-up studies were performed for 2 to 4.2 years (mean 2.8). ST-T changes on the electrocardiogram at rest or during exercise were present in 6 patients before balloon valvuloplasty and had disappeared in all at 6-month follow-up. Reoccurrence of ST-T changes after a longer follow-up was associated with severe valve regurgitation. Syncope was not observed after balloon valvuloplasty. The continuous-wave Doppler gradient decreased from 94 +/- 36 to 49 +/- 15 mm Hg (p less than 0.001). After a follow-up of 2 to 4.2 years (mean 2.8) it remained unchanged (43 +/- 13 mm Hg; p = not significant).(ABSTRACT TRUNCATED AT 250 WORDS)     

Percutaneous transluminal valvuloplasty of calcific aortic stenosis in elderly patients. Role of noninvasive evaluation by Doppler echocardiography

Between October 1986 and January 1989, 57 attempts of percutaneous transluminal valvuloplasty were made in 51 elderly patients, mean age 76.7 +/- 6.2 years, with symptomatic aortic stenosis; this included 3 failures and 6 repeat valvuloplasties. The procedure resulted in a significant immediate decrease of the peak-to-peak transaortic pressure gradient from 94.6 +/- 26.5 to 42.6 +/- 17.9 mm Hg (p less than 0.002) and an increase of the surface of the aortic valve from 0.4 +/- 0.1 to 0.6 +/- 0.2 cm2 (p less than 0.001). Cardiac output remained unchanged: 3.8 +/- 0.9 vs 3.8 +/- 0.8 lit/min. Complications included local vascular injury requiring surgical repair in 7 patients, cerebral events in 3 patients and disruption of the aortic annulus, the aortic wall and the pulmonary artery each in 1 patient, and resulted in 4 in-hospital deaths (8%). Follow-up data were available for all patients for a mean duration of 12.7 +/- 5.4 months. Fifteen patients (30%) died on average 9.0 +/- 4.9 months after discharge. Recurrence of symptoms and early restenosis were documented in the majority of the patients. Restenosis was successfully treated by repeat valvuloplasty in 4 and by valve replacement in 4 patients. Doppler echocardiography predicted the severity of the aortic stenosis before valvuloplasty and was very useful to assess follow-up results. Because of the limited hemodynamic results, the numerous procedural complications and the development of early restenosis balloon valvuloplasty of aortic stenosis should be restricted to selected symptomatic elderly patients.     

Early and late changes in left ventricular systolic performance after percutaneous aortic balloon valvuloplasty

To evaluate early and late hemodynamics after aortic valvuloplasty, 17 patients underwent first-pass radionuclide angiocardiography with simultaneous high-fidelity micromanometer pressure before, 10 minutes after and 6 months after aortic valvuloplasty. Pressure-volume and stress data were assessed. Immediately after the procedure, no significant change was observed in heart rate, systemic blood pressure, cardiac output or aortic insufficiency (as measured by visual or quantitative aortography). The mean and peak transvalvular gradient decreased from 64 to 36 mm Hg (p less than 0.001) and 76 to 38 mm Hg (p less than 0.001), respectively. The mean aortic valve area increased from 0.5 to 0.8 cm2 (p less than 0.001). Using echocardiography, meridional end-systolic wall stress decreased from 81 to 63 x 10(3) dynes/cm2 (p less than 0.001). Left ventricular ejection fraction increased from 0.48 to 0.54 (p less than 0.01), end-diastolic volume decreased from 161 to 143 ml (p less than 0.001) and end-diastolic pressure decreased from 18 to 13 mm Hg (p less than 0.01). Left ventricular stroke work (the area of the pressure-volume loop) also decreased from 17.5 to 14.7 x 10(6) ergs (p less than 0.001). The loop shifted to the left and downward. At the 6-month study, the mean and peak aortic valve gradient increased from 36 to 56 mm Hg (p less than 0.001) and 38 to 61 mm Hg (p less than 0.001), respectively.(ABSTRACT TRUNCATED AT 250 WORDS)     

Balloon valvuloplasty for recurrent aortic stenosis after surgical valvotomy in childhood: immediate and follow-up studies

The immediate and intermediate-term effects of balloon valvuloplasty were assessed at cardiac catheterization in nine children with recurrent stenosis after a previous surgical aortic valvotomy. At valvuloplasty the patients ranged in age from 0.35 to 16 years and had undergone surgical valvotomy 0.3 to 12.5 years previously. Balloon valvuloplasty immediately reduced the peak systolic aortic stenosis gradient by 53%, from 88 +/- 9 (mean +/- SEM) to 41 +/- 6 mm Hg (p = 0.004). The left ventricular systolic pressure was reduced from 189 +/- 8 to 157 +/- 8 mm Hg (p = 0.001) and the left ventricular end-diastolic pressure from 17 +/- 1 to 14 +/- 2 mm Hg (p = 0.025). The heart rate and cardiac index remained unchanged. Before valvuloplasty, one patient had 1 + and two patients had 2+ aortic insufficiency. In six of nine patients, balloon valvuloplasty caused no change in the degree of valvular insufficiency. Two patients had a 1 + increase (from 0 to 1 + insufficiency in both), and one patient with no insufficiency developed 2+ aortic insufficiency. Elective follow-up catheterization was performed 0.8 to 2.5 years (mean 1.5 +/- 0.2) after valvuloplasty. At follow-up, the peak aortic stenosis gradient remained significantly reduced from the gradient before valvuloplasty (37 +/- 5 versus 85 +/- 10 mm Hg, p = 0.002). The gradient had not changed significantly from that measured immediately after valvuloplasty (37 +/- 5 versus 38 +/- 5 mm Hg, p = 0.75). At follow-up, aortic insufficiency had decreased from that immediately after valvuloplasty in three patients and had increased in two.(ABSTRACT TRUNCATED AT 250 WORDS)     

Immediate and short-term effects of aortic balloon valvuloplasty on left ventricular diastolic function and filling in humans

The effect of aortic balloon valvuloplasty on left ventricular diastolic function and filling was investigated in 44 adult patients with severe aortic stenosis. Two-dimensional and Doppler echocardiography was performed in all patients before and 24 h after valvuloplasty. In 19 patients (short-term group) repeat studies were performed at 3 (n = 2) and 6 (n = 17) months. Left ventricular relaxation, chamber stiffness and filling were assessed in 16 patients (immediate post-valvuloplasty group) before and immediately after valvuloplasty by simultaneous micromanometer left ventricular pressure tracings and echocardiograms. Immediately after valvuloplasty, relaxation was slightly impaired in the immediate post-valvuloplasty group, as reflected by the isovolumic relaxation time constant (56 +/- 26 to 68 +/- 39 ms; p less than 0.01) and maximal negative dP/dt (2,063 +/- 640 to 1,767 +/- 495 mm Hg/s; p less than 0.001). The chamber stiffness constants and diastolic filling dynamics were unchanged immediately after valvuloplasty. Twenty-four hours after valvuloplasty, patients without mitral regurgitation (n = 24) showed increases in the peak early filling velocity (72 +/- 31 to 83 +/- 28 cm/s; p less than 0.05) and peak early to atrial filling velocity ratio (0.8 +/- 0.6 to 1.0 +/- 0.7; p less than 0.05). However, in patients with mitral regurgitation (n = 20), the diastolic filling dynamics were not significantly changed. In the short-term group at the 3 to 6 month follow-up period, patients without mitral regurgitation (n = 12) showed striking increases compared with pre-valvuloplasty values in the peak early filling velocity (66 +/- 21 to 93 +/- 31 cm/s; p less than 0.02), peak early to atrial filling velocity ratio (0.6 +/- 0.2 to 0.9 +/- 0.4; p less than 0.02) and early time-velocity integral (9 +/- 4 to 16 +/- 6 cm; p less than 0.002). In patients with mitral regurgitation (n = 7) decreases occurred in the peak early filling velocity (123 +/- 32 to 106 +/- 28 cm/s; p less than 0.05) and peak early to atrial filling velocity ratio (1.5 +/- 0.7 to 1.1 +/- 0.6; p less than 0.05). Functional class in hospital improved after valvuloplasty (3.1 +/- 1.0 to 2.6 +/- 0.9; p less than 0.001) and correlated modestly with the percent decrease in Doppler-derived peak gradient (rs = 0.41, p less than 0.02) and mean gradient (rs = 0.36, p less than 0.05), but did not correlate with changes in aortic valve area, left ventricular ejection fraction or diastolic filling variables.(ABSTRACT TRUNCATED AT 400 WORDS)     

Echocardiographic assessment of aortic valve area in elderly patients with aortic stenosis and of changes in valve area after percutaneous balloon valvuloplasty

Echocardiographic studies, adequate for analysis of aortic valve area using the continuity equation, were obtained in 31 patients aged greater than or equal to 60 years who were undergoing catheterization for assessment of suspected aortic stenosis. Catheterization-determined aortic valve area was 0.74 +/- 0.30 cm2 (mean +/- SD) and Doppler-determined aortic valve areas were 0.68 +/- 0.27 and 0.65 +/- 0.27 cm2, depending on whether peak or mean velocities, respectively, were entered into the continuity equation. There were significant correlations between both of the Doppler-derived and the catheterization-determined aortic valve areas (r = 0.86, p less than 0.001 for both the continuity equation employing peak velocities and the continuity equation employing mean velocities) which were demonstrated to be linear by F test (catheterization area = -0.03 + 1.13 X Doppler area determined using peak velocities, SEE = 0.163 cm2, p less than 0.001; and catheterization area = -0.02 + 1.16 X Doppler area determined using mean velocities, SEE = 0.165 cm2, p less than 0.001). Both sets of correlations had linear regression parameters meeting the conditions for identity. Significant linear correlations were also noted between the non-invasive measurements of aortic valve excursion, ventricular ejection time, time to one-half carotid upstroke, maximal Doppler velocity and maximal Doppler gradient and catheterization aortic valve area, but the correlations were less tight than those between valve areas determined by catheterization and by Doppler continuity equation. Ten of the patients underwent percutaneous balloon aortic valvuloplasty. There were significant linear correlations between aortic valve areas determined by Doppler and catheterization methods both before valvuloplasty (r = 0.77, p = 0.01; p less than 0.001 by F test, SEE = 0.134 cm2) and after valvuloplasty (r = 0.85, p less than 0.01; p = 0.0001 by F test, SEE = 0.161 cm2). Linear regression parameters met the conditions for identity. There was also a significant linear correlation between catheterization and Doppler measurements of absolute change in aortic valve area (r = 0.79, p less than 0.01; p less than 0.001 by F test, SEE = 0.11 cm2). Aortic valve area can be determined reliably by continuity equation in elderly patients. In addition, results of balloon valvuloplasty, measured by changes in catheterization-determined aortic valve area, are accurately reflected by changes in aortic valve area determined using the continuity equation.     

Orifice variability of the stenotic aortic valve: evaluation before and after balloon aortic valvuloplasty

The effects of balloon aortic valvuloplasty on orifice variability of the stenotic sclerocalcific aortic valve were evaluated by hemodynamic measurements of aortic valve function in 14 patients before balloon aortic valvuloplasty, during nitroprusside infusion before valvuloplasty, 48 h after valvuloplasty and during nitroprusside infusion 48 h after valvuloplasty. Aortic valve function was assessed by aortic valve area calculations with use of the Gorlin and Cannon formulas. Nitroprusside infusion before balloon aortic valvuloplasty caused no change in mean aortic valve gradient but a significant increase in mean aortic transvalvular flow from 186 +/- 46 to 202 +/- 61 ml/s (p less than 0.05), in Gorlin aortic valve area from 0.49 +/- 0.17 to 0.53 +/- 0.21 cm2 (p less than 0.05) and in Cannon aortic valve area from 0.45 +/- 0.18 to 0.49 +/- 0.22 cm2 (p less than 0.05). Nitroprusside infusion 48 h after valvuloplasty induced no change in mean aortic valve gradient but a significant increase in mean aortic transvalvular flow from 214 +/- 61 to 254 +/- 78 ml/s (p less than 0.005), in Gorlin aortic valve area from 0.71 +/- 0.25 to 0.83 +/- 0.32 cm2 (p less than 0.01) and in Cannon aortic valve area from 0.78 +/- 0.33 to 0.88 +/- 0.40 cm2 (p less than 0.05). Forty-eight hours after valvuloplasty, nitroprusside infusion induced a larger increase (40 +/- 40 ml/s) in mean transvalvular flow than before valvuloplasty (16 +/- 27 ml/s; p less than 0.05) and a larger increase (0.12 +/- 0.14 cm2) in Gorlin aortic valve area than before valvuloplasty (0.05 +/- 0.07 cm2; p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)     

Hemodynamic results of percutaneous aortic balloon valvuloplasty as assessed by sequential Doppler echocardiographic studies

We determined the sequential hemodynamic changes after percutaneous aortic balloon valvuloplasty by means of two-dimensional and Doppler echocardiographic examinations in 25 patients immediately before, immediately after, and 24 to 36 hours after valvuloplasty. An aortic valve area was determined at all three time periods by using the continuity equation from the Doppler velocity profiles. The aortic valve area by Doppler echocardiography immediately before valvuloplasty correlated with that determined by cardiac catheterization (r = 0.85, SEE = 0.08 cm²). The mean aortic valve gradient by Doppler echocardiography was 50 ± 22 mm Hg before the procedure, decreasing to 29 ± 12 mm Hg (P < 0.001), with a small, but significant, increase 1 day later to 33 ± 13 mm Hg (P < 0.001). The mean subvalvular velocity increased from 0.44 ± 0.13 to 0.52 ± 0.15 m/sec immediately after valvuloplasty (P < 0.001), increasing further to 0.60 ± 0.16 m/sec 1 day later (P < 0.001). The resultant aortic valve area increased from 0.45 ± 0.11 to 0.73 ± 0.18 cm² immediately after (P < 0.05). One day later, the aortic valve area increased further to 0.86 ± 0.19 cm² (P < 0.05). Because of the dynamic changes occurring during the first 24 to 36 hours after balloon valvuloplasty, hemodynamic measurements taken immediately after the procedure may underestimate the efficacy of this technique.     

Echocardiographic evaluation of mitral valve structure and function in patients followed for at least 6 months after percutaneous balloon mitral valvuloplasty

Although beneficial results have been reported immediately after percutaneous mitral balloon valvuloplasty, little information is available concerning the longer-term outcome of this procedure. The anatomic and functional results of percutaneous mitral valvuloplasty were assessed in 20 patients, in whom two-dimensional and Doppler echocardiographic examination could be obtained both immediately and 6 to 11 months (mean 7.5 +/- 2.0) after balloon dilation. Mean valve area measured by planimetry decreased slightly but significantly from 1.90 +/- 0.59 cm2 immediately after valvuloplasty to 1.62 +/- 0.55 cm2 (p less than 0.001) at follow-up. Individual changes in valve area were variable, and in four patients valve area decreased by greater than 25%. Echocardiographic scores of valvular morphology were obtained by assigning scores of 0 to 4 (with increasing abnormality) to each of four morphologic characteristics of the valve, namely, leaflet mobility, thickening, calcification and subvalvular thickening. This score was higher in the four patients with a decrease in valve area greater than 25% at follow-up than in the other patients (11 +/- 2 versus 7 +/- 2, p less than 0.002). Multiple regression analysis of several hemodynamic and echocardiographic factors identify first the echocardiographic score and second the valve area postvalvuloplasty as the only significant predictors of the percent decrease in valve area (r = 0.70, p less than 0.006). Mitral regurgitation graded by pulsed Doppler ultrasound decreased from 1.9 +/- 1.2 immediately after valvuloplasty to 1.0 +/- 0.9 (p less than 0.003) at follow-up, whereas there was no change in mean transmitral pressure gradient by Doppler echocardiography (5 +/- 2 versus 6 +/- 3 mm Hg, p = NS) and left atrial volume (74 +/- 34 versus 72 +/- 27 cm3, p = NS). Thus, 6 to 11 months after balloon mitral valvuloplasty, mean mitral valve area decreases slightly. Individual changes in valve area, however, are variable. Valvular morphology assessed by two-dimensional echocardiography may be useful for identifying those patients who have an increased likelihood of developing valvular restenosis.     

Lack of sustained clinical improvement in an elderly population after percutaneous aortic valvuloplasty

The hemodynamic and clinical results following 25 percutaneous aortic valvuloplasty (PAV) procedures on 24 patients are reported. The mean aortic gradient decreased from 66 +/- 23 to 40 +/- 15 mm Hg (p less than 0.001) and the mean valve area increased from 0.5 +/- 0.17 to 0.7 +/- 0.26 cm2 (p less than 0.001). Although the aortic gradient determined by both Doppler and direct measurement correlated well before PAV, the Doppler gradients determined 24 +/- 48 hours after the procedure were significantly higher than the directly measured gradients at the time of PAV. Ninety-two percent of patients were New York Heart Association class III or IV before PAV. Of the remaining 12 patients, 6 (50%) were classified as class II, 2 (17%) were class III, and 4 were (33%) class IV. Necropsy examination of the patient who died shortly after valvuloplasty revealed localized hematoma and tear in the anterior mitral valve leaflet. Smaller initial valve areas yielded smaller valve areas after PAV. Patients with greater valve areas following PAV showed greater functional improvement. Only 7 patients (29%) had at least 1 functional class improvement at the final follow-up. PAV can be performed relatively safely in elderly, moribund patients, although sustained improvement of functional status is not common. In this population, PAV should be limited to patients severely symptomatic in whom surgery is not an acceptable option.     

Results of balloon valvuloplasty in typical and dysplastic pulmonary valve stenosis: Doppler echocardiographic follow-up

To assess the usefulness of balloon valvuloplasty in patients with a dysplastic pulmonary valve, the files of 36 patients (aged 1 day to 18.5 years) who had two-dimensional echocardiography before and continuous wave Doppler echocardiography late after balloon valvuloplasty (balloon diameter greater than or equal to 20% anulus diameter) were reviewed. Results of relief of pulmonary stenosis were graded by catheter gradient in the catheterization laboratory and compared with Doppler echocardiographic findings at follow-up. There were 32 patients with typical pulmonary stenosis and 4 with a dysplastic valve. In the 32 patients with typical pulmonary stenosis, transvalvular gradient changed from a mean of 67 +/- 32 to 20 +/- 20 mm Hg (p less than 0.0001, mean reduction 72.6%). The gradients at follow-up by Doppler echocardiography averaged 20 mm Hg including 15 that increased, 3 that were unchanged and 14 that decreased. Only 3 (9%) of 32 patients had a gradient greater than 25 mm Hg at follow-up and only one gradient was greater than 35 mm Hg. All four patients with a dysplastic valve had a gradient that decreased with valvuloplasty from a mean of 85 +/- 33 to 33 +/- 20 mm Hg (p less than 0.05); gradient reduction in this group ranged from 40 to 85% (mean 57.5%). The gradient at follow-up increased in three of these four patients and decreased in one (the only late gradient less than 25 mm Hg). Late gradient was less than 35 mm Hg in two of the four patients and was reduced by 43 and 57%, respectively, in the other two.(ABSTRACT TRUNCATED AT 250 WORDS)     

Balloon valvuloplasty for critical aortic stenosis in the newborn: influence of new catheter technology

Between 1986 and July 1990, balloon valvuloplasty was attempted in eight newborns (less than 28 days of age) with isolated critical aortic valve stenosis. Balloon valvuloplasty could not be successfully accomplished in any of the three infants presenting before 1989. Since March 1989, when improved catheter technology became available, all five neonates presenting with critical aortic stenosis were treated successfully by balloon valvuloplasty. A transumbilical approach was utilized in all four infants in whom umbilical artery access could be obtained. One newborn who was 25 days of age underwent transfemoral balloon valvuloplasty. Balloon valvuloplasty was immediately successful in all five newborns, as evidenced by a decrease in valve gradient and improvement in left ventricular function and cardiac output. Peak systolic gradient was reduced by 64% from 69 +/- 8 to 25 +/- 3 mm Hg (p = 0.005). Left ventricular systolic pressure decreased from 128 +/- 9 to 95 +/- 9 mm Hg (p = 0.02) and left ventricular end-diastolic pressure decreased from 20 +/- 2 to 11 +/- 1 mm Hg (p = 0.02). Moderate (2+) aortic regurgitation was documented in two infants after valvuloplasty. The time from first catheter insertion to valve dilation averaged 57 +/- 14 min (range 26 to 94) and the median length of the hospital stay was 4 days. With the use of recently available catheters, the transumbilical technique of balloon valvuloplasty can be performed quickly, safely and effectively in the newborn with critical aortic stenosis. It does not require general anesthesia, cardiopulmonary bypass or a left ventricular apical incision and it preserves the femoral arteries for future transcatheter intervention should significant aortic stenosis recur.     

Changes in left ventricular systolic performance immediately after percutaneous aortic balloon valvuloplasty

To evaluate the acute changes in left ventricular (LV) performance before and immediately after percutaneous aortic valvuloplasty, 25 patients underwent first-pass radionuclide angiocardiography for construction of pressure-volume loops. Simultaneously, high-fidelity micromanometric aortic and LV pressures were recorded. Echocardiographic wall thickness was used to define wall stress. After valvuloplasty, no acute changes were observed in the heart rate, aortic systolic pressure, cardiac output or degree of aortic insufficiency. Valvuloplasty decreased the peak aortic valve gradient from 73 to 40 mm Hg (p less than 0.001) and the mean gradient from 61 to 30 mm Hg (p less than 0.001); aortic valve area increased from 0.55 to 0.80 cm2 (p less than 0.001). Meridional end-systolic wall stress decreased from 83 to 55 X 10(3) dynes/cm2 (p less than 0.01). LV ejection fraction increased from 0.41 to 0.48 (p less than 0.01). LV end-diastolic volume decreased from 186 to 160 ml (p less than 0.001), end-systolic volume decreased from 115 to 87 ml (p less than 0.001) and end-diastolic pressure decreased from 22 to 17 mm Hg (p less than 0.01). LV stroke work decreased from 16.0 to 14.0 X 10(6) erg (p less than 0.001). No change was observed in peak positive LV dP/dt or the end-systolic pressure-volume ratio. This study documents variable and complex changes in the measures of cardiac function after aortic valvuloplasty. A decrease in the amount of LV outflow obstruction with maintenance of the cardiac output at a decreased level of LV filling occurs.