Tricuspid aortic valve with partial commissural fusion: prelminary report of an apparently common cause of aortic ejection sounds with potential for serious sequelae, illustrated by two cases.

We report the cases of 2 patients whose tricuspid aortic valves were found to have partial commissural fusion. Both patients experienced complications that were probably related to this abnormality: bacterial endocarditis in 1 instance and a lacunar stroke in the other. In order to illustrate the similarity of physical findings, we also describe the case of a 3rd patient, who had a typical bicuspid aortic valve. Tricuspid aortic valve with partial commissural fusion has been described in autopsy series and has been predicted to cause an ejection sound, but we could find no previously published description of this lesion in living patients. We wish to alert others to the possible presence of aortic commissural fusion, to its potential for serious and likely preventable sequelae, and to the ability of carefully performed transthoracic high-resolution digital echocardiography to demonstrate this condition when its characteristics are found on physical examination.

The integration of clinical practice and research: the challenge of the new millenium. The Joseph Rutenfranz Lecture.

The integration of clinical activities and fundamental research is usually not made in most investigations. This lecture, in honor of Joseph Rutenfranz, examines the work of several investigators who participated in the PWP meeting in Italy in 1999 and suggests different ways that their work could be applicable to both basic and clinical scientists. The goal is to stimulate research in pediatric exercise physiology and pathology that is meaningful for all interested in the field.

Exercise capacity and incidence of myocardial perfusion defects after Kawasaki disease in children and adolescents.

OBJECTIVES: This study evaluated exercise performance and myocardial perfusion during exercise in patients with Kawasaki disease who had a broad spectrum of residual coronary abnormalities. BACKGROUND: Reports of exercise performance after Kawasaki disease have generally included a small number of patients evaluated by various protocols, frequently with incomplete data. Myocardial perfusion studies have usually been limited to those using pharmacologically induced coronary vasodilation. Therefore, to our knowledge there has not been a large study directly correlating exercise performance, electrocardiographic (ECG) changes and myocardial perfusion imaging. METHODS: Forty-six patients were classified into three groups on the basis of coronary artery status: group 1 (n = 27) had no objective evidence of coronary artery lesions; group 2 (n = 11) had resolved aneurysms; group 3 (n = 8) had persistent coronary aneurysms. All patients underwent exercise testing with monitoring of ECG changes and oxygen consumption. Single-photon emission computed tomographic imaging was performed at rest and during peak exercise using technetium-99m sestamibi. RESULTS: Maximal oxygen consumption was within normal limits and was similar for all three groups. Five patients had mild ST segment changes at peak exercise. Two of these patients had stress-induced perfusion defects. Myocardial perfusion defects were present in 37% of patients in group 1, 63% in group 2 and 100% in group 3. Perfusion defects corresponded to the coronary artery lesion site in all but three patients. CONCLUSIONS: Maximal oxygen consumption is normal after Kawasaki disease regardless of coronary artery status. Stress-induced perfusion defects are frequent even in the absence of coronary abnormalities and are common in the absence of ST segment changes suggestive of ischemia.

Cardiopulmonary exercise testing in children following surgery for tetralogy of Fallot.

The purpose of this study was to compare the cardiopulmonary responses at rest and during exercise of children following surgical correction of tetralogy of Fallot. The physiologic measurements assessed at rest and during maximal treadmill exercise included diffusing capacity of the lung for carbon monoxide, heart rate, oxygen consumption, minute ventilation, and cardiac output. Twenty children with repaired tetralogy of Fallot served as the study group, and 20 normal boys and girls served as controls. Subjects with tetralogy of Fallot had significantly lower values than those of control subjects for maximal cardiac output and somewhat lower values for diffusing capacity of the lung for carbon monoxide and heart rate. We conclude that the exercise cardiac function of children with surgically corrected tetralogy of Fallot is somewhat diminished compared with that of control children. This information is necessary to establish safe, yet effective exercise guidelines for this select population.

Doppler echocardiographic evaluation of tilting-disc prosthetic heart valves in children.

To determine the Doppler characteristics of tilting-disc prosthetic heart valves in children, 22 children with mitral prostheses were studied 8 +/- 2 months after surgery, and 10 children with aortic prostheses were studied 37 +/- 26 months after surgery. All valves were thought to be functioning normally by clinical examination. Valve competence was interrogated and peak and mean velocities were measured by standard pulsed wave, continuous wave and color Doppler techniques. Prosthetic valve area was calculated and compared to the known valve area. Mild prosthetic valve regurgitation was present in 8 of 22 mitral and 7 of 10 aortic prostheses. For mitral prostheses, peak velocity was 192 +/- 41 cm/s, mean velocity was 118 +/- 37 cm/s and mean gradient was 7 +/- 4 mm Hg. For aortic prostheses, peak velocity was 287 +/- 88 cm/s, mean velocity was 197 +/- 59 cm/s, peak gradient was 36 +/- 21 mm Hg and mean gradient was 19 +/- 11 mm Hg. Prosthetic mitral valve area, calculated by the pressure half-time and modified Gorlin methods, correlated well with the known valve area (r = 0.89, standard error of the estimate = 0.29 and r = 0.95, standard error of the estimate = 0.21, respectively). Prosthetic aortic valve area, calculated by the modified Gorlin method, correlated well with the known valve area (r = 0.89, standard error of the estimate = 0.18). Residual valvular abnormalities are common after prosthetic valve insertion in children. Doppler estimates of prosthetic valve area correlate well with the known valve area but have a large standard error of the estimate.

Flexibility and Strength Measures in Children Participating in a Cardiac Rehabilitation Exercise Program.

In brief: The purpose of this study was to evaluate the effects of a structured rehabilitation program on the strength and flexibility of children with surgically corrected congenital heart disease. Twelve children (eight boys, four girls) participated in one-hour exercise classes, two times per week for 12 weeks. Results showed minimal changes in upper extremity strength, but lower extremity strength improved 10% and 5% on the right and left sides, respectively. Flexibility improved about 25% in the lower extremities. Improvement was also noted in neck flexion, hip and oblique rotation, hamstring and low back stretch, and heel cord stretch. These findings indicate that this type of program can improve strength and flexibility in children who have undergone complex heart surgery and may help them achieve a more normal life-style.

Small left atrium and change in contour of the ventricular septum in total anomalous pulmonary venous connection: a morphometric analysis of 22 infant hearts.

Morphometric measurements of 22 hearts with total anomalous pulmonary venous connection (TAPVC) were compared with measurements of 8 matched control specimens without heart disease. Each of the TAPVC specimens had a shorter left atrium, smaller left atrial surface area and larger diameter of the fossa ovalis. In addition to increased length of the right ventricle and larger circumferences for tricuspid and pulmonary valve anuli, the left ventricular contour of the ventricular septum was flat or convex in 18 of the 22 hearts; the septum was significantly longer than normal in these specimens and wider at its midportion. Because mitral and aortic valve anuli were normal in circumference, the data suggest that left ventricular volume is not decreased despite change in ventricular shape.

Repair of anomalous origin of the left coronary artery in the infant and small child.

Anomalous origin of the left coronary artery from the pulmonary artery is associated with myocardial infarction, left ventricular dysfunction, mitral valve dysfunction and, occasionally, intracardiac congenital abnormalities. A technique that utilizes a flap of the anterior wall of the pulmonary artery to serve as a neocoronary artery to direct aortic flow from a created aortopulmonary window to the pulmonary artery orifice of the anomalous left coronary artery was used in five patients aged 2.5 months to 4.75 years. Two patients were less than 4 months of age at operation. There was one death 2 days after operation and one late death. The two youngest patients required mitral valve replacement. Two of the three surviving patients are well at follow-up at 7 to 44 months. One patient has been lost to follow-up study. One patient had postoperative catheterization which showed an intact repair. The pulmonary artery neocoronary procedure is applicable to infants and small patients with anomalous origin of the left coronary artery from the pulmonary artery.

Use of the rebreathing method in the differential diagnosis of congenital heart disease and persistent fetal circulation.

The differential diagnosis of congenital heart disease from persistent fetal circulation is clinically difficult and cardiac catheterization is often needed. The development of a safe, new technique for use of the rebreathing method has allowed the determination of effective pulmonary blood flow, lung tissue volume, lung diffusion capacity and functional residual capacity in 7 critically ill, ventilator-dependent infants at the bedside. Analysis of the data revealed highly significant differences for lung tissue volume and diffusion capacity, a minimally significant difference for effective pulmonary blood flow and no difference for functional residual capacity between the groups. Use of this method allows not only attainment of clinically useful information but also permits better insight into the pathophysiology of the disease state.

Evaluation of a gastric tube with esophageal balloon for neonatal use.

A gastric tube with esophageal balloon was designed for neonatal use. The response of the balloon was evaluated. In vitro studies involved comparisons of pressure changes (delta P) in a flask, as measured directly, or as transferred via the balloon. Values for delta P ranged frm 5 cmH2O to 40 cmH2O, and frequencies from 10 to 1620 cycles per minute. The volume of air within the balloon was varied from 0.1 to 0.4 ml. At each combination of pressure, frequency and balloon volume, the balloon transmitted an accurate, if minimally lower delta P, than that imposed. In a rabbit, intraesophageal delta Ps measured via the balloon were compared with intrapleural delta Ps, measured via a chest tube. The frequency rates and delta Ps achieved were similar to those encountered in the clinical situation. The delta s measured via the balloon were frequently equal to or sometimes minimally lower than the actual pleural pressure changes. The prototype meets recommended dimensions for esophageal balloon use in the neonate and allows for accurate routine measurements for calculation of pulmonary function. The device is now available commercially.

Physical fitness in children with hemophilia.

Eleven boys, 8.3 to 15.5 (mean 11.6) years old, with hemophilia, were studied by bicycle ergometry to determine their physical fitness. Parameters analyzed and compared to data for normal children included total work, mean power minutes of exercise, heart rate (HR), and blood pressure (BP), as well as catecholamine levels. The hemophilic child performs significantly less total work (67%), mean power (49%), minutes of exercise, (30%), and HR (8%). There were no differences in BP. Norepinephrine rose from a resting level of 204.5 to 652pg /ml after exercise, and epinephrine rose from 20.5 to 76.6pg/ml, levels comparable to those achieved by normal children during exercise. Children with hemophilia demonstrate poor exercise performance, which we believe is due to a lack of physical conditioning. Recommendations are made for individual exercise prescriptions to improve the fitness of these children.

Changes in coagulation parameters with exercise in patients with classic hemophilia.

Vigorous exercise is known to increase VIII:C and VIIIR:Ag levels transiently in normal individuals. Although exercise programs are frequently advocated in the management of hemophilia, the effects of exercise on coagulation parameters in these patients have not been well studied. Eleven hemophiliacs were exercised on a bicycle ergometer to maximum voluntary effort as evidenced by an increase in pulse, blood pressure, and plasma catecholamine (norepinephrine and epinephrine) levels. The effects of this exercise on coagulation parameters, including functional and antigenic components of the factor VIII molecule, were determined. The entire group demonstrated a decrease in mean prothrombin time (11.7 to 11.2 sec). Four mild hemophiliacs demonstrated an increase in mean VIII:C (14.5% to 17.3%), and VIII:CAg (12% to 17.8%). Changes in VIII:C and VIII:CAg were not noted in the seven severe hemophiliacs. Both severe and mild patients demonstrated significant changes in fibrinogen, factor II, and factor VII after exercise. This study indicates that submaximal exercise modifies coagulation parameters in patients with hemophilia.

Left ventricular false tendons in children: prevalence as detected by 2-dimensional echocardiography and clinical significance.

During a 28-month period, consecutive 2-dimensional echocardiograms were reviewed to determine the prevalence of left ventricular (LV) false tendons, their associated anomalies and clinical significance. LV false tendons were found in 31 (0.8%) of 3,847 consecutive 2-dimensional echocardiograms. Of 31 LV false tendons, 30 passed longitudinally from papillary muscle to septum and 1 went from free wall to free wall. The 31 patients were aged 1 day to 15 years. Associated heart disease, most often ventricular septal defect, bicuspid aortic valve and coarctation of the aorta, was present in 48%, of whom 73% were girls. Of those without heart disease, 69% were boys. In patients with heart disease, precordial murmurs were due to the underlying cardiac anomaly. Of those without heart disease, 15 of 16 (94%) had a precordial murmur, usually of the Still's type over the lower left sternal border. Four of 31 (13%), 1 with and 3 without heart disease, had unifocal premature ventricular contractions that were rate-dependent in the 2 patients undergoing stress testing. LV false tendons appear to occur in 0.8% of pediatric patients and usually are accompanied by a Still's type innocent murmur if unassociated with heart disease. Some LV false tendons are associated with rate-dependent premature ventricular contractions.