Joan M. Sigmann

Ventricular septal defect: Results after repair in infancy

During the 19 years from 1957 through 1975, there have been 106 patients under age 2 years who have undergone surgery for repair of a large ventricular septal defect at the University of Michigan Medical Center. The majority of the patients had either severe pulmonary hypertension or intractable congestive heart failure. Eighty-three infants survived operation; there has been one late death. The greatest mortality occurred in patients under age 6 months and in those with severe pulmonary hypertension. Surviving infants showed marked symptomatic improvement and change in growth patterns. Complications included the development of complete right bundle branch blodk or left anterior hemiblock in approximately 50 percent of patients and, in one instance, complete atrioventricular block. Forty-five patients have undergone cardiac catheterization 1 to 8 years postoperatively. Although 17 were found to have residual septal defects only 3 of these had a pulmonary to systemic flow ratio of 1.5:1 or more, and reoperation was accomplished without incident in these 3 patients and in 3 others with smaller shunts. With one exception, postoperative pulmonary arterial pressures and pulmonary to systemic vascular resistance ratios were normal or near normal, thus representing a significant contrast with findings in patients operated on after age 2 years. Whereas the complications of surgery appear no greater in the infant than in the older patient, many of the benefits can be realized only with operation at the earlier age.

The Surgical Therapy for Pulmonary Artery—Right Ventricular Discontinuity

Abstract The results of operations performed at the University of Michigan for conditions characterized by pulmonary artery-right ventricular discontinuity are reviewed. In 5 infants with increased pulmonary blood flow, pulmonary artery banding was performed with unsatisfactory results. Two survived operation but later died of complications related to the bands. Fourteen children received shunts for conditions involving reduced pulmonary blood flow; 13 survived and have either undergone subsequent total repair or are doing well and are awaiting total repair when possible. Twelve patients have undergone total repair; valveless cloth tube conduits were utilized in 4, and 2 remain well 11 years later. More recently, fresh, antibiotic-preserved aortic allografts have been utilized for the conduit. Six of 8 patients survived the operation, and there was 1 late death. The aortic wall of one graft became calcified after 4 years and had to be replaced, although the valve leaflets remained functional. Immediate success of the totally corrective operation depends on the pulmonary vascular resistance being less than 60% of the systemic. Long-term success depends on the fate of the conduit. From previous experience we think fresh allografts should be more durable than the sterilized allografts used by most other groups; however, we have found that even fresh allografts can calcify.

Estimation of pulmonary/systemic resistance ratios from echocardiographic systolic time intervals in young patients with congenital or acquired heart disease

Previous work has shown the positive correlation of echocardiographic right ventricular preejection period/right ventricular ejection time ratio (RPEP/RVET) with pulmonary vascular resistance and pulmonary arterial diastolic pressure obtained at cardiac catheterization. However, the correlation was insufficient to predict pulmonary arterial diastolic pressure or vascular resistance from a given RPEP/RVET ratio. In this study the RPEP/RVET ratio was compared with left ventricular preejection period/ejection time ratio (LVEP/LVET) in 25 patients undergoing cardiac catheterization, and a strong correlation was found between the ratio (RPEP/RVET)/(LPEP/LVET) = R/L and the ratio of pulmonary arteriolar resistance/systemic arteriolar resistance (PAR/RS), especially when R/L was correlated with log10 PAR/RS (r = 0.902). A very high correlation (r = 0.960) was found between R/L and log10 PAR/RS when the group was restricted to patients with a ventricular septal defect or a complete endocardial cushion defect. Regression equations for prediction of PAR/RS have been derived for the various groups.

Tetralogy of fallot: Factors influencing the mortality rate of total correction

Abstract Total correction of tetralogy of Fallot was carried out in 215 patients from 1957 through mid-1967. Twenty-eight patients died during the period of hospitalization following the operation, and 5 died later. The operative mortality rate declined steadily throughout the period, reaching 2.2 per cent in the last 22 months. The major factors determining the outcome of surgical treatment were the age of the patient, the severity of the cardiac deformities, the beneficial effects of a prior systemic-pulmonary shunt, associated cardiac lesions, and the surgical technic. Total correction between the ages of 6 and 14 carries the most favorable prognosis. When young patients are severely cyanotic, it is better to establish a palliative systemic-pulmonary artery shunt, preferably by the Blalock-Taussig technic, and subsequently carry out the total repair when the patient is from 6 to 9 years old. This procedure enhances the childs normal development in the interim and establishes more favorable conditions for the later operation.

An emergency method of handling broken pacemaker wires in children

Abstract A simple emergency method for handling pacemaker failures, devised under the pressure of an actual emergency in a young child, can be extended to all types of pacemaker failure by placing “spare” electrodes in the myocardium and bringing the wires to an accessible subcutaneous area on the chest wall. At the time of pacemaker failure, these wires can be uncovered, with the patient under local anesthesia, and attached to a transistorized external pacemaker.

Coronary sinus enlargement in infants. A diagnostic note.

A well-localized, curvilinear, extrinsic defect on the anterior wall of the barium-filled esophagus in infants (D7-D8Ievel) may indicate enlargement of the coronary sinus due to increased blood flow secondary to either a persistent left superior vena cava or an anomalous pulmonary venous return. Recognition of this possibility should enable the selection of a more suitable route for cardiac catheterization and angiocardiography.