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To evaluate the risks of and optimal method for valve dilation in aortic stenosis, balloons of different sizes were used to dilate the normal aortic root in 16 lambs and then stenotic valves in 15 children. In the lambs, inflated balloon to aortic anulus diameter ratios ranged from 0.9 to 1.5. These hearts were examined immediately after the procedure. Ratios of 0.9 to 1.1 did not produce significant damage to the left ventricular outflow tract, whereas those of 1.2 to 1.5 produced tears or hematomas, or both, of the aortic valve leaflets (n = 3), mitral valve leaflets (n = 4) and interventricular septum (n = 4).

As children with cardiac disease grow older, atrial flutter becomes more prevalent. A collaborative study was performed in 19 institutions to determine the clinical characteristics of these children and the factors affecting prognosis. There were 380 patients with one or more electrocardiographically documented episodes of atrial flutter that first occurred between ages 1 and 25 years (mean age at onset 10.3). Episodes of flutter continued to occur for a mean of 2.5 years after the onset. Of the 380 patients, 60% had repaired congenital heart disease, 13% palliated congenital heart disease, 8% unoperated congenital heart disease, 8% an otherwise normal heart, 6% cardiomyopathy, 4% rheumatic heart disease and 2% other lesions.

The records of 90 patients with Wolff-Parkinson-White syndrome who presented with supraventricular tachycardia in the first 4 months of life were reviewed. Among these, 63% were male. Structural heart disease was present in 20%, most commonly Ebstein's anomaly. All patients presented with a regular narrow QRS tachycardia, and pre-excitation became evident only when normal sinus rhythm was established. Only one infant had atrial flutter and none had atrial fibrillation. Type A Wolff-Parkinson-White syndrome was most common (49%), with heart disease occurring in only 5% of these patients. In contrast, heart disease was identified in 45% of those with type B syndrome.

Balloon dilation was attempted in 16 patients, aged 5 months to 19.5 years, with right ventricular outflow obstruction after repair of congenital heart defects. Stenosis of a valved conduit between the pulmonary ventricle and pulmonary artery was present in nine patients with a mean transvalvular peak systolic ejection gradient of 61.6 ± 21.0 mm Hg and a mean right ventricle to aorta pressure ratio of 0.9 ± 0.2. Supravalvular pulmonary stenosis was present in seven patients; in five, stenosis was at the anastomotic site after the arterial switch operation with a mean peak systolic ejection gradient of 72.2 ± 10.6 mm Hg and mean right ventricle to aorta pressure ratio of 0.93 ± 0.05. The other two patients had stenosis at a previous pulmonary artery band site with a peak systolic ejection gradient of 60 and 65 mm Hg and right ventricle to aorta pressure ratio of 0.75 and 0.72, respectively.

Percutaneous transvenous balloon mitral valvotomy was performed successfully in a 57 year old man with refractory congestive heart failure due to calcific mitral stenosis. Cardiac surgery was not an option because of other major medical problems. Balloon mitral valvotomy was performed using the transseptal technique. The interatrial septum was dilated with the use of an 8 mm balloon catheter to allow passage of larger balloon valvotomy catheters to the mitral anulus. The procedure resulted in a marked decrease in the diastolic transmitral gradient from 20 to 4 mm Hg. This decrease was associated with an increase in cardiac output from 3.4 to 5.7 liters/min. Mitral valve area increased from 0.7 to 2.5 cm2. Balloon valvotomy did not result in significant mitral regurgitation. This case indicates that further trials are warranted to evaluate percutaneous transseptal mitral valvotomy for the treatment of patients with mitral stenosis.

A 75 year old man with long-standing rheumatic mitral stenosis who refused surgical intervention was treated with percutaneous balloon valvuloplasty. Prevalvuloplasty evaluation revealed a heavily calcified mitral valve, a mean transvalvular gradient of 18 mm Hg, a Fick cardiac index of 1.7 liters/min per m2, a mitral valve area of 0.6 cm2and 1+ mitral regurgitation. After transseptal catheterization and balloon dilation of the interatrial septum with an 8 mm angioplasty balloon, a 25 mm valvuloplasty balloon was advanced over a guide wire across the interatrial septum and positioned across the mitral anulus. Subsequent balloon inflation at 3 atm pressure resulted in a reduction of the mean mitral valve gradient to 12 mm Hg, an increase in cardiac index to 2.5 liters/min per m2, an increase in mitral valve area in 1.4 cm2and an increase in mitral regurgitation from 1+ to 2+. Valvuloplasty was well tolerated without embolization of clot or valvular debris, and resulted in marked clinical improvement with decreased dyspnea and increased exercise tolerance.

Between January 1973 and July 1981, 128 patients less than 1 year of age with failure to thrive, congestive heart failure or pulmonary artery hypertension underwent primary repair of a ventricular septal defect. The hospital mortality rate was 7.8% (10 of 128), and the late mortality rate was 2.3% (3 of 128). Mortality was highest among younger infants with preexisting respiratory problems or a hemodynamically significant residual lesion postoperatively. Complications included a large residual shunt in eight (6.2%), transient neurologic problems in five (3.9%) and persistent complete heart block in three (2.3%). Lung biopsy specimens obtained from 49 patients showed pulmonary vascular abnormalities in all. Complete right bundle branch block developed in 74 (64%) and bifascicular block appeared in 11 (9%).

Percutaneous balloon valvotomy was attempted in 27 patients (aged 6 days to 19 years, median 2 years, 11 months) with unoperated typical valvular pulmonary stenosis using a balloon 7 to 60% (mean 30%) larger than the valve anulus. One patient had undergone a previous balloon valvotomy elsewhere. To achieve an oversized dilation diameter in three larger patients, two balloons were inflated side by side. Their “effective dilation diameter” was determined by the diameter of the circle with the same area as that of the oval enveloping the two balloons.

Nine cases are reported of perimembranous ventricular septal defect associated with left ventricular to right atrial shunting. Cineangiographic findings included an aneurysm of the membranous septum in all patients; two patients had obvious adherence of deformed tricuspid valve leaflets to the membranous septum. The location of the ventricular septal defect was confirmed at surgery or cardiac endoscopy in seven patients. In the presence of a perimembranous ventricular septal defect, left ventricular to right atrial shunting is usually the result of tricuspid valve abnormalities, including clefts or perforations of the septal leaflet, deformity or adherence of valve tissue to the margins of the septal defect and widening of the anteroseptal commissure. Biplane left ventriculography, using the long axial oblique and reciprocal right anterior oblique projections, may best demonstrate the pathologic anatomy, although the he-patoclavicular projection is a useful alternative, particularly when an atrioventricular canal defect is a diagnostic consideration.

Gianturco coils were used to embolize 77 vessels in 54 patients: 58 aortopulmonary collateral vessels, 14 Blalock-Taussig shunts, 3 arteries involved in pulmonary sequestrations and 2 venae cavae. Embolization resulted in total occlusion in 53 (69%), subtotal occlusion in 19 (25%) and partial occlusion in 3 (1 intentional). Two embolizations failed to reduce flow. Thus, 72 (95%) of 76 embolizations in which complete occlusion was the intended result resulted in total or subtotal occlusion. Analysis of the results demonstrates that completely occluded collateral vessels were longer and had a smaller diameter than did incompletely occluded vessels.

Validation of a totally noninvasive method for estimating instantaneous left ventricular pressure and constructing a pressure waveform throughout ejection in patients with aortic stenosis is reported. In 20 patients (aged 8.75 ± 10 years) with congenital aortic stenosis (measured peak left ventricular pressure 120 to 260 mm Hg; transvalvular gradient 18 to 165 mm Hg), transaortic valve continuous wave Doppler ultrasound, indirect carotid pulse tracing, peripheral blood pressure and measured left ventricular pressure were recorded simultaneously at cardiac catheterization. Data were entered into a microcomputer using a digitizing tablet and the instantaneous Doppler gradient was calculated and added to instantaneous aortic pressure, derived from the time-corrected and calibrated carotid pulse tracing, to estimate instantaneous left ventricular pressure.

Although balloon dilation or valvular pulmonary stenosis is established in infants and children, the techniques for and results of balloon dilation in neonates with critical pulmonary stenosis remain largely unreported. Since January 1, 1985, six successive neonates with critical pulmonary stenosis (aged 1 to 6 days) underwent attempted balloon dilation. Each was cyanotic and three of the six were on prostaglandin E1therapy and three required tracheal intubation and ventilation. All had suprasystemic right ventricular pressures (mean 122.8 ± 6.6 mm Hg).