Milton H. Paul

Discrete subvalvular aortic stenosis in childhood: Study of 51 patients

Fifty-one children with discrete subvalvular aortic stenosis were studied between 1951 and 1974. The three anatomic types of obstruction found were the thin membranous type (43 cases), the fibromuscular collar type (5 cases) and the tunnel type (3 cases). The obstruction was usually severe, and the median left ventricular to aortic systolic pressure gradient was 90 mm Hg. Progressive obstruction with an increasing gradient was documented in 10 patients by serial cardiac catherizations. Significant associated cardiac defects, present in 57 percent of patients, often masked the typical clinical and cardiac catheterization features of subaortic stenosis. The stenosis was often not discovered until after surgery for the associated defect. Forty patients underwent surgical resection of the discrete subaortic obstruction. After surgery significant left ventricular to aortic pressure gradients can be found at postoperative cardiac catheterization. These gradients may reflect inadequate resection of the more complex discrete obstructions or represent proliferation and regrowth of the previously resected subvalvular fibrous tissue. The criteria for operability of discrete subaortic stenosis should be the angiographic demonstration of a discrete subvalvular diaphragm and the presence of a resting left ventricular to aortic systolic pressure gradient of 40 mm Hg or more.

Clinical,angiocardiographic, and pathologic findings in 100 patients

Salient clinical, hemodynamic, angiocardiographic, and pathologic findings are presented in 100 patients with truncus arteriosus communis, 79 of whom were studied at autopsy. In this study of typical truncus, all had a ventricular septal defect (type A). Truncus with a partially formed aorticopulmonary septum (type A1) was much the commonest form (50%). Cases with no remnant of aorticopulmonary septum (type A2) were second in frequency (21%). The distinction between types A1 and A2 could not be made with certainty in 9%, because these types merge into one another. Cases with absence of either pulmonary artery branch (type A3) were the least frequent form (8%). Truncus with interruption, atresia, preductal coarctation, or severe hypoplasia of the aortic arch (type A4) constituted 12%. The diagnosis of truncus is primarily angiocardiographic. The plane of the truncal valve in the lateral projection is distinctive. It tilts anteriorly, facing the patients toes, which can be of assistance in differential diagnosis. The angiocardiographic features of type A4, although unfamiliar, are pathognomonic. Since the median age at death was only 5 weeks, and in view of the difficulties associated with pulmonary artery banding, our goal should be the surgical correction of truncus during the first and second months of life.

Pulmonary vascular disease in complete transposition of the great arteries: A study of 200 patients☆

Abstract Lung specimens of 200 patients with transposition of the great arteries were examined microscopically for evidence of pulmonary vascular disease. In patients with an intact ventricular septum or a small ventricular septal defect, advanced pulmonary vascular disease was uncommon; only 9 of 107 such patients (8.4 percent) demonstrated greater than grade 2 (Heath-Edwards) pulmonary vascular disease. A persistent large patent ductus arteriosus appeared to promote progressive pulmonary vascular disease in this group since each of the five infants less than 1 year of age with grade 3 or 4 disease had this lesion. In contrast, pulmonary vascular disease was common in patients with a large ventricular septal defect; 37 of 93 patients (40 percent) with this defect had greater than grade 2 pulmonary vascular disease. Among patients more than 1 year of age, 26 of 35 (75 percent) had grade 4 disease. The catheterization data suggest that the calculated pulmonary vascular resistance may underestimate the degree of disease, probably by overestimating the pulmonary blood flow (Fick method). Pulmonic stenosis appeared to protect the lungs from progressive pulmonary vascular disease, and pulmonary arterial banding was protective when performed before age 6 months. Our studies indicate that a persistent large patent ductus arteriosus should be closed as early as possible in view of its association with advanced pulmonary vascular disease in these patients. In infants with a large ventricular septal defect, pulmonary arterial banding or corrective surgery with closure of the defect should be performed between the ages of 4 and 6 months to prevent progressive pulmonary vascular damage.

Experimental production of hypoplastic left heart syndrome in the chick embryo

Abstract The hypothesis is examined that hemodynamic alterations at the site of the primordial mitral valve may induce malformations that simulate the clinical findings of hypoplastic left heart syndrome. Surgical placement of a nylon device, approximately 90 μ in diameter, into the region of the left atrioventricular (A-V) canal was accomplished in 192 embryos (Hamburger-Hamilton stages 23 to 25). Thirty-nine pairs of experimental and control embryos survived more than 12 days. Twenty-six experimental embryos exhibited various malformations: hypoplastic left atrium and ventricle, mitral valvular atresia, aortic valvular stenosis and tubular hypoplasia of the aorta and brachlocephalic vessels. These findings reemphasize the probable morphogenetic role of blood flow pathways. The findings further implicate involvement of the left A-V canal as well as premature closing of foramen ovale and aortic valvular abnormalities in the hypoplastic left heart syndrome.

Exercise Studies in Tetralogy of Fallot: A Review

Exercise evaluation of patients with congenital heart disease in general and tetralogy of Fallot in particular has had much less impact on clinical care than that of adults with coronary heart disease. Of over 4000 references on tetralogy of Fallot in the literature since 1965, only 87 involve exercise. These studies were reported from 56 institutions, with 39 originating from the United States and Canada, 40 from Europe, and 8 from Japan. They involved 3157 patients, studied mostly after intracardiac repair (ICR). In reviewing these data one is struck by the wide range of different approaches to exercise testing. This is in part related to the different purposes of each exercise study, but it also relates to the lack of uniform standards for exercise testing in patients with congenital heart disease. The studies involved maximal treadmill exercise and maximal or submaximal cycle ergometer work, in the upright or supine position, utilizing 52 different work protocols, the most common being the Bruce treadmill protocol (employed 27 times). Despite this lack of standardization exercise evaluation has significantly contributed understanding of the natural history and pathophysiology of surgically corrected tetralogy of Fallot.

Relation between preoperative left ventricular muscle mass and outcome of the fontan procedure in patients with tricuspid atresia

The relation between preoperative left ventricular muscle mass and clinical outcome of the Fontan procedure was evaluated retrospectively in 22 patients with tricuspid atresia who were selected for this physiologic surgical correction by conventional hemodynamic criteria. Patients were divided into two groups: group A (excellent or good outcome) and group B (poor outcome or death) based on the clinical course assessed up to 9.5 years postoperatively. Thirteen of 22 group A patients did not have prolonged, clinically significant, systemic venous hypertension and were not on long-term diuretic drug therapy. Nine of 22 group B patients either had clinically significant systemic venous hypertension, required long-term diuretic drug therapy or died (3 patients). Age at surgery, pulmonary arteriolar resistance, left ventricular ejection fraction, end-diastolic volume, end-diastolic pressure, systemic oxygen saturation and pulmonary to systemic blood flow ratio (Qp/Qs) were not statistically different between the two groups. Left ventricular muscle mass, both in group A patients (92 +/- 31 g/m2) and in group B patients (146 +/- 61 g/m2), was greater than the normal mean value (p less than 0.01 and p less than 0.001, respectively). Left ventricular muscle mass in group B was significantly greater than in group A (p less than 0.01). Furthermore, left ventricular muscle mass/end-diastolic volume (mass/volume) ratio, reflecting the extent of left ventricular hypertrophy relative to volume overload, was significantly greater in group B (1.1 +/- 0.28) than in group A (0.84 +/- 0.21) (p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Pulmonary vascular disease in complete atrioventricular canal defect

The incidence and time of occurrence of pulmonary vascular disease were studied in 67 children with the complete form of atrioventricular (A-V) canal defect. Advanced pulmonary vascular disease begins to develop during the first year of life, with intimal fibrosis (grade 3 cahnges) noted between age 6 months to 1 year. Vascular dilatation with plexiform lesions (grade 4 changes) can be found by age 1 year. These changes can be found in some patients in spite of hemodynamic findings usually considered to indicate lesser degrees of vascular disease. After age 2 years advanced pulmonary vascular disease is commonly found and may persist after surgical correction of the defects. A similar rapid progression of pulmonary vascular disease was noted in 40 children who had a large ventricular septal defect without A-V canal in whom systemic pressure was transmitted directly to the pulmonary vascular bed. Thirty-six of the 67 children had trisomy-21. No difference was noted in the speed of progression of pulmonary vascular disease between these children and those without trisomy 21. Palliative or corrective surgery should be performed in these patients by age 1 year to prevent development of advanced pulmonary vascular disease.

Congenital Absence of the Pulmonary Valve The Clinical Syndrome of Tetralogy of Fallot with Pulmonary Regurgitation

A group of cases of tetralogy of Fallot with congenital absence of the pulmonary valve are presented, and it is indicated that this abnormality presents a characteristic clinical, physiologic, and pathologic syndrome. It is postulated that the aneurysmal dilatation of the pulmonary artery may result either from a congenital weakness at the base of the pulmonary artery or from the hemodynamic effects of a ventricular septal defect and infundibular stenosis in the presence of pulmonary regurgitation. The absence of the pulmonary valve has not been a deterrent to successful corrective surgery aimed at the basic pathology of tetralogy of Fallot in three cases.

Neonatal polycythemia with transient cyanosisand cardiorespiratory abnormalities

Ten infants with transient plethora and cyanosis in the newborn period are presented,with findings suggestive of transient cardiovascular strain. A search for common etiologic factors revealed considerable elevation in the hematocrit and hemoglobin levels consistent with neonatal polycythemia. The several sources of neonatal hypervolemia and polycythemia are discussed; it seems likely that an excessive transfusion of placental blood at delivery is an important factor. Spontaneous improvement generally occurs although phlebotomy has been therapeutically applied in two instances.

Lack of connection between the atria and the more peripheral conduction system in congenital atrioventricular block

Abstract The hearts in 7 cases of congenital atrioventricular (A-V) block due to absence of or diminution in the connection between the atria and the A-V node or bundle (in the absence of the A-V node) were studied by serial section. In 3 cases the A-V node was present; it was buried in the central fibrous body and the atrioventricular portion of the pars membranacea. In 3 cases the A-V node was absent, but the more peripheral portion of the conduction system was intact. In all of these cases, the block was shown to be supraventricular by electrocardiogram. In the seventh case, the A-V node was absent and the A-V bundle and right bundle branch were also defective. It is suggested that this disease is due to a malformation of the central fibrous body during the absorption of the bulbus, which causes the obliteration of the atrial muscular connections to the A-V node and may also injure the conduction system.