Intraoperative transesophageal echocardiography of coronary artery fistulas.

Coronary artery fistula is a rare abnormality but one with substantial surgical importance, as operation abolishes the fistulous shunt volume, progressive coronary dilatation, and potential coronary steal. Prior reports emphasize the utility of direct inspection on cardiopulmonary bypass, with visualization of drainage of blood or cardioplegia from the fistulous connection, to define the drainage site. We report 3 patients in whom intraoperative transesophageal echocardiography was used for precise localization of the fistulous drainage site, selective demonstration of vessels feeding the fistulas, and documentation of abolition of fistulous flow, all without need for cardiopulmonary bypass. In addition, the technique provides for continuous monitoring of ventricular function, providing the opportunity to detect inadvertent ischemic effects of ligation. This approach appears to have considerable utility.

Pediatric cardiovascular effects of imipramine and desipramine.

Electrocardiograms were evaluated in 39 children and adolescents before and after the clinical use of imipramine and desipramine. The average increase in PR interval was 0.01 seconds. The PR interval increased by 0.02 seconds in 11 subjects, and a new first-degree atrioventricular block developed in two subjects. These changes were not related to the choice between imipramine and desipramine, the dose, or the method of administration. An increase in PR interval by 0.02 seconds or more did correlate with having an abnormality disclosed on a pretreatment electrocardiogram. The average increase in PR interval was 0.007 seconds for subjects with normal baseline electrocardiograms and 0.019 seconds for subjects with conduction and nonconduction abnormalities disclosed in baseline tracings. None of the electrocardiogram changes resulted in adverse clinical consequences.

Tetralogy of Fallot: selective staged management.

One hundred twenty-four patients with tetralogy of Fallot have undergone either primary total repair (61), shunt and later repair (30), or an initial shunt (33). The mean ratio of pulmonary anulus to descending thoracic aorta increased from 0.80 +/- 0.25 before the shunt to 1.22 +/- 0.26 before the repair (p less than 0.0001). The mean ratio in the primary repair group was 1.23 +/- 0.25. A transannular patch was necessary in only six of 91 patients (6.6%). Postrepair right ventricular/left ventricular pressure ratio averaged 0.50 +/- 0.11 in the shunt plus repair group and 0.43 +/- 0.12 in the primary repair group. Only four patients had a right ventricular/left ventricular pressure ratio less than 0.65. A significant inverse linear relationship existed between this ratio and the pulmonary anulus size measured at operation and normalized for the patient's height (p less than 0.01). Postoperative complications occurred in 21% of patients after a shunt and 20% of patients after open heart repair. The early mortality was 0.8% (1/124). An initial shunt in patients with a small pulmonary anulus can result in an increased anulus size and better hemodynamic result with frequent avoidance of a transannular patch. Staged repair may result in improved overall mortality rates.

Hemodynamic effects of ketamine in children with congenital heart disease.

Pulmonary and systemic vascular responses to ketamine (2 mg X kg-1, intravenously) were studied during cardiac catheterization in 20 children with congenital heart lesions. Pulmonary and systemic resistances (Rp, Rs), ratios between pulmonary and systemic flows (Qp/Qs), and left to right (L----R) and right to left shunts (R----L) were calculated before and after ketamine administration. Statistically significant (P less than 0.05) but clinically minor increases in heart rate (106.8 to 109.9 beats/min), mean pulmonary artery pressure (20.6 to 22.8 mm Hg), and Rp/Rs (0.12 to 0.14) were seen after ketamine. There were no significant changes in systemic arterial pressure, Rs, Qp/Qs, L----R, R----L, or arterial oxygen or carbon dioxide tensions. No patient had any major untoward effects from ketamine administration. It is concluded that the hemodynamic alterations after ketamine administration in children undergoing cardiac catheterization are small and do not alter the clinical status of the patients or the information obtained by cardiac catheterization.

Pulsed Doppler echocardiographic evaluation of ventricular septal defect patches.

Doppler echocardiography has been shown to have high sensitivity and specificity for noninvasive detection of the flow disturbance of ventricular septal defect. After surgery for ventricular septal defect, one might expect loss of the ventricular septal defect flow disturbance. We used two-dimensional and pulsed Doppler echocardiography to evaluate 30 children undergoing surgery for ventricular septal defect to determine postoperative Doppler findings and the effect of ventricular septal defect patch material on those findings. Twenty-one patients had Dacron patches and nine pericardial patches. Doppler examinations were performed immediately after surgery and at intervals thereafter. The patches were imaged on two-dimensional echocardiograms and the Doppler method was used to evaluate flow at the patches. Doppler echocardiography was also used to estimate volume flow in the aorta and pulmonary artery to estimate postoperative ratio of pulmonary to systemic flow (Qp/Qs). Immediately after surgery 93% of patients had a flow disturbance detected by Doppler echocardiography in the region of the surgically placed patch. On postoperative day 1, 62% of Dacron-patched defects and 66% of pericardial patched defects showed evidence of residual shunting on Doppler examination. By the third postoperative day, this prevalence fell to 23% and 44%, respectively. By 2 weeks after surgery there was evidence of residual shunting in only two patients. In 26 of 30 early postoperative Qp/Qs estimates were under 1.6/1; all but two of these lost the Doppler-detected flow disturbance by 2 weeks after surgery. In three of 30 Qp/Qs estimates exceeded 1.9/1; two of these three required reoperation.(ABSTRACT TRUNCATED AT 250 WORDS)

Cardiac surgery under age two years. A review.

To assess the current status and risks of both open and closed cardiac procedures for congenital heart disease in patients under the age of 2 years, we reviewed all cardiac catheterizations and cardiac operations done from January, 1974, through December, 1977, at The Children's Orthopedic Hospital and Medical Center in Seattle, Washington. In this interval 370 patients under 2 years of age were catheterized. Eighty open procedures were performed in patients under 2 years of age, with seven hospital deaths. One hundred twenty-four closed heart procedures were performed on children under the age of 2 years, with eight deaths, for a hospital mortality rate of 6.5 percent. This review of consecutive cases over a 4 year period suggests that the judicious application of palliation or open repair using current techniques can lead to an overall mortality rate of between 6 and 7 percent for both open and closed heart procedures in children under 2 years of age. Since all deaths except one in the open-heart group occurred in patients with the most complex multiple defects, it seems reasonable to suggest that improved intraoperative and postoperative techniques have lowered the time for repair of straightforward congenital heart defects to under 2 years of age.

Radical enlargement of the aortic root and outflow tract to allow valve replacement.

A method of radical enlargement of the aortic root and outflow tract is described. The technique consists of incising the aortic annulus, the anterior mitral leaflet, and the superior aspect of the left atrium. Valve replacement is then possible, with patch reconstruction of the resulting defects.

Subdural hematoma following open-heart operations.

Six patients who died following open-heart operations were found at postmortem examination to have acute subdural hematomas. On the basis of the clinical and postmortem findings, two factors in the pathogenesis of the hemorrhage are postulated. In the presence of intraoperative heparin administration, significant hematoma formation may result from damage to the bridging dural veins from minor, inadvertent head trauma or alterations in cerebral volume from fluid shifts. Manipulation of the head in patients who have been given heparin should be undertaken with extreme care, particularly in infants. In any patient with neurological dysfunction who has also had an open-heart operation, the possibility of an expanding subdural hematoma must be considered.