Norman J. Sissman

Developmental landmarks in cardiac morphogenesis: Comparative chronology☆

Abstract Data concerning the chronology of anatomic changes in the developing heart in a group of seven frequently studied species are presented in tabular form. Different modes of expression of levels of embryonic maturation for these species are correlated and listed. Examples of the possible significance of temporal sequences and of quantitative alterations accompanying the progression of developmental landmarks in cardiac morphogenesis are discussed.

Spontaneous Closure of Physiologically Advantageous Ventricular Septal Defects

The clinical and pathological features of two cases in which physiologically advantageous ventricular septal defects closed spontaneously are presented. The first patient, with tricuspid atresia, Type I(c), developed symptoms and signs of increasing systemic hypoxemia, decreasing pulmonary blood flow, and a systolic murmur of decreasing intensity. His ventricular septal defect, previously demonstrated angiocardiographically, could not be found at autopsy; it is presumed to have closed by fusion of its muscular rims with subsequent covering by endocardial proliferation. The second patient, with a double-outlet right ventricle, demonstrated progressive left ventricular enlargement and congestive failure despite increasing pulmonary vascular resistance. Postmortem examination showed that this defect was sealed by adherence of the septal leaflet of the tricuspid valve to the edges of the defect. Appreciation of the true nature of the changing anatomical situation would have resulted in more rational effective therapeutic approaches.The cases presented and review of pertinent literature contribute to more complete understanding of circumstances surrounding the spontaneous closure of ventricular septal defects.

Bidirectional Shunting in a Coronary Artery-Right Ventricular Fistula Associated with Pulmonary Atresia and an Intact Ventricular Septum

A case of an anomalous arteriovenous-like communication between the right ventricle and a single right coronary artery with pulmonary atresia and an intact ventricular septum in a 6-year-old boy is presented. The dynamics of blood flow through the anomalous vessel are demonstrated for the first time in the literature by means of cineangiocardiography. Factors affecting the flow of blood through the vessel, theories of the embryologic etiology of the condition, and clinical features allowing diagnosis during life and determining therapeutic management are discussed.

The Relationship of Pulmonary Venous Wedge to Pulmonary Arterial Pressures

A comparison of pressure levels and pressure-time relationships in pulmonary artery pressure (PAP) and pulmonary venous wedge pressure (PVWP) tracings was made from cardiac catheterization records of 60 patients, aged 1 day to 16 years. In 50 patients with normal or low PAPs there was close correlation between systolic, diastolic, and mean pressures in the two sites. In all 10 patients with pulmonary hypertension the PVWPs were elevated but were significantly different from corresponding PAPs. The wave contours showed qualitative similarities in most cases, but the duration of the rise in systolic pressure was longer, and the Q-pressure intervals were delayed in the PVWP tracings. Satisfactory PVWPs were obtained in 42 of 67 (63%) consecutive patients approached from the leg. Lack of correlation of pressures from the two sites in the presence of pulmonary hypertension may be attributed, in part, to decreased compliance of the pulmonary arterial system. It is concluded that the PVWP is useful in catheter evaluation of heart disease: when the PVWP is normal it usually reflects accurately the PAP; an elevated PVWP suggests an elevated PAP but cannot be used reliably as an indication of the actual arterial pressure.

Correction of Absence of the Aortopulmonary Septum by Creation of Concentric Great Vessels

An 18-year-old patient is reported who had simultaneous occurrence of aortopulmonary septal absence, complete interruption of the aortic arch, and patent ductus arteriosus. This is the only known patient who has had total anatomical correction of this combination of defects. Correction was accomplished by staged procedures; the first stage consisted of obliteration of the patent ductus and establishment of aortic continuity; this was followed one year later by the second stage, which included a unique method for repair of absence of the aortopulmonary septum. The surgical desirability and embryological implications of criteria for differentiating truncus arteriosus from aortopulmonary septal defect are presented. Follow-up physiological evaluations and the patients death from the effects of increasing pulmonary vascular disease (despite early symptomatic improvement) approximately two years after completion of the repair underscore the importance of early diagnosis and operative intervention.

The electrocardiogram in supravalvular aortic stenosis

Abstract Analysis of hemodynamic, ECG, and clinical data in 26 patients with SVAS shows an incidence of ECG abnormalities similar to that in comparable series of patients with VAS. One or more of three ECG signs, voltage criteria of left ventricular hypertrophy, abnormally wide frontal plane QRS angle, or left ventricular strain, segregated patients with severe and mild left ventricular outflow obstruction; but lack of correlation in the group with medium degrees of obstruction and individual exceptions in all three categories make the ECG a clinically unreliable means of assesing the severity of SVAS. The findings do not support the theory of myocardial hypoxia as the pathogenesis of abnormal S-T-T wave changes in left ventricular hypertrophy. However, the unknown incidence in this group of patients of previously described coronary obstruction from adherent aortic valve leaflets or premature coronary intimal and medial thickening, and the unavailability of actual coronary flow data make any definitive conclusion unwarranted.

A modification of the fluorescein circulation time

Abstract An arm-to-tongue circulation time with 3 c.c. of 15 per cent sodium fluorescein has been described. It is different from those previously reported in that the tongue has been used as an end point. Careful complete histories and physical examinations were obtained on normal patients to establish a valid control series. The circulation times on fifty normal individuals gave results which very closely approximated those previously reported with other drugs. The results on the twenty-five patients with congestive heart failure also closely approximated those previously reported but were outstanding in that there were no failures noted with sodium fluorescein.

The Pulmonary Pressures in Pulmonary Venous Obstruction

The contour of the pulmonary artery wedge pressure tracing in a case of pulmonary venous obstruction was unique and may be diagnostic. Wedged pressures were obtained in both a pulmonary artery and a pulmonary vein on recatheterization of a 5-year-old boy with total anomalous pulmonary venous drainage to the superior vena cava on whom an anastomosis of the confluence of the pulmonary veins to the left atrium with loose ligation of the vertical vein had been done at 2 months of age. The pulmonary artery wedge pressure (oxygen saturation, 97%) was 31/18 (mean, 22) mm Hg and its contour was almost identical to that of the pulmonary artery pressure. A similar contour was obtained in the pulmonary vein, for both wedged and free pressures. The similarity of the pulmonary artery wedge pressure to that in the free pulmonary artery may lead to the conclusion that the catheter is not wedged when actually it is. Doubt can be resolved by withdrawing fully saturated blood. Extreme stenosis between the confluence of the pulmonary veins and the left atrium may cause the pulmonary artery wedge to reflect pulmonary arterial rather than left atrial pressure and pulse form.