David G. Ruschhaupt

Cardiac Status in Juvenile Borderline Hypertension

A prospective M-mode echocardiographic study was done to look for early cardiovascular changes in children prone to hypertension with blood pressures between the 75th and 95th percentiles for age. Average systolic/diastolic pressures in 27 children with borderline hypertension were 137/89 mm Hg compared to 110/68 mm Hg for the 26 controls. Echocardiographic measurements were normalized for comparison using two methods. The borderline hypertensive group mean values were significantly greater than controls for left ventricular wall thickness (p less than 0.05 for method 1; p less than 0.001 for method 2), left ventricular mass (p less than 0.001; p less than 0.005) and left ventricular wall thickness to radius ratio (p less than 0.001, both methods). Echocardiographic estimates of left ventricular function were lower in the hypertensive group. This study suggests that cardiac hypertrophy can be shown by noninvasive means in some children before arterial pressure becomes elevated. To assess the incidence and possible consequences of early target organ changes, more extensive clinical evaluation of borderline hypertension in children is recommended.

Spectrum of pulmonary sequestration: Association with anomalous pulmonary venous drainage in infants

SummaryPulmonary sequestration is a spectrum of related lesions, each of which may be absent or present: (1) bronchial sequestration of pulmonary parenchyma; (2) arterial supply from systemic circulation; (3) anomalous pulmonary venous drainage to the right atrium; (4) communications between bronchus and esophagus; (5) defects of diaphragm; (6) gross lung anomalies, such as horseshoe lungs or hypoplasia. Any combination of these primary lesions can occur in an individual patient. Diagnosis should be directed towards each component of the spectrum. Of special importance is the venous connection, as anomalous pulmonary venous drainage can involve not only the sequestered segment but the entire ipsilateral lung, making surgical therapy far more complex. Treatment of choice is surgical resection, associated, if needed, with rerouting of the pulmonary venous return.Classification of sequestration of the lung as intra- and extralobar is of secondary importance: these 2 groups do not represent lesions of different embryological significance.

Electrophysiologic abnormalities of children with ostium secundum atrial septal defect

Sinus node (SN) and atrioventricular node (AVN) function were evaluated in 49 patients with secundum type atrial septal defect (ASD). Automaticity and conduction system function were assessed by intracardiac recording of the AH and HV intervals at rest, corrected SN recovery time, sinoatrial conduction time, AVN refractory period and the ability of the AVN to conduct rapidly paced atrial beats to the ventricles. Electrophysiologic abnormalities were found in 41% of the 34 patients who were studied before surgery. However, no preoperative abnormalities were present in children younger than 2.5 years. If only children older than 2.5 years were analyzed, the incidence of conduction abnormalities was similar for the patients studied before operation (62%) and those studied after operation (71%). The size and ejection fractions of the right and left ventricles, the magnitude of shunt flow and the size of the ASD did not differ between the patients with and those without electrophysiologic abnormalities. AVN dysfunction was present in 40% of the patients who were studied after surgical repair. While this frequency was more than twice the preoperative incidence of AVN dysfunction, it was not statistically significant. The data suggest that patient age is the major factor that influences the presence of conduction system dysfunction in patients with ASD.

Friedreich's ataxia associated with idiopathic hypertrophic subaortic stenosis

Abstract Friedreichs ataxia and idiopathic hypertrophic subaortic stenosis (IHSS), both diseases of unknown etiology, both result in hypertrophy and degenerative changes of the myocardium. Both diseases lead to nearly identical electrocardiographic changes. We report a patient who developed classical signs of Friedreichs ataxia several years after he was found to have moderately severe IHSS. This observation prompted a hemodynamic study of five other patients with Friedreichs ataxia in search of a more common association and thus a possible etiological link between the two diseases. Cardiac catheterization was performed under local anesthesia. Catheters were inserted into the right ventricle, the pulmonary artery, the left ventricle, and the aorta. Isuprel infusion up to 6 μg per minute was used in an attempt to induce an abnormal pressure gradient across the right or left ventricular outflow tract. Both right and left ventricular cineangiograms were obtained for evaluation of ventricular kinetics and wall thickness. Right and left heart pressures were normal at rest in all patients. During Isuprel infusion a 40 mm. pressure gradient was induced across the left ventricular outflow tract in only one patient. A second patient developed a 16 mm. gradient across the right ventricular outflow tract. All patients had low normal cardiac outputs. The angiograms demonstrated increased left ventricular wall thickness in all patients. It is concluded that systolic left and/or right ventricular out-flow tract obstruction is only infrequently present in Friedreichs ataxia and is mild in degree. An etiological link between Friedreichs ataxia and IHSS is not known at the present but may possibly exist and should be investigated.

Mitral valve malformation of ebstein type in absence of corrected transposition

The first documented case is reported of mitral valve malformation of the Ebstein type in the absence of corrected transposition. In this case, the ring of the inferior leaflet of the mitral valve was displaced downward into the left ventricle, dividing the latter into a proximal atrialized and a distal effective ventricular chamber. The anterior leaflet was not displaced. The chordae tendineae of both leaflets were thickened. The papillary muscles were hypertrophied and abnormal in architecture. The outflow tract of the effective left ventricle was shortened. The valve leaflets were thickened, and the mitral valve was probably insufficient.

Estimation of circumferential fiber shortening velocity by echocardiography

The M-mode and two-dimensional echocardiograms of 40 young patients were analyzed to compare the mean circumferential fiber shortening velocity (Vcf) of the left ventricle calculated separately by two methods. The mean circumferential fiber shortening velocity was derived from the M-mode echocardiogram as minor axis shortening/ejection time and derived from the two-dimensional echocardiogram as actual circumference change/ejection time. With computer assistance, circumference was determined from the short-axis two-dimensional echocardiographic images during end-diastole and end-systole. Good correlations were obtained between the left ventricular diameter derived by M-mode echocardiography and the vertical axis during end-diastole (r = 0.79) and end-systole (r = 0.88) derived by two-dimensional echocardiography. Likewise, high correlations were noted between diameter and circumference in end-diastole (r = 0.89) and end-systole (r = 0.88). However, comparison of Vcf obtained by M-mode echocardiography with that obtained by two-dimensional echocardiography showed only fair correlation (r = 0.68). Moreover, the diameter/circumference ratio determined in end-diastole and end-systole differed significantly (p less than 0.001), possibly owing to the change in geometry of the ventricular sector image during systole. Although Vcf derived by M-mode echocardiography is a useful index of left ventricular performance, it does not truly reflect the circumference change during systole.

Complete heart block from mycoplasma pneumoniae infection

SummaryComplete heart block (CHB) in infants and children is usually congenital. Nonsurgical acquired CHB is rare. Occasionally, transient acquired CHB is seen in association with viral myocarditis. We describe here an unusual case of transient CHB in a 12-year-old boy with endomyocardial biopsy-proven myocarditis and evidence ofMycoplasma pneumoniae infection.

Aortic origin of the RPA: Immediate resolution of severe pulmonary artery hypertension by surgical repair

SummaryAortic origin of the right pulmonary artery (AORPA) is a rare condition requiring a high index of suspicion for diagnosis as the usual signs of structural heart disease are often absent. Ultrasound examination can strongly suggest the condition but can easily be misinterpreted. Infants should be considered “operable” even when the resistance calculations predict otherwise as there appears to be a large component of immediately reversible pulmonary artery hypertension. With technical skills learned from arterial switch operations (for transposition of the great arteries), surgical repositioning of the RPA should be possible in nearly all cases without the use of a tube graft.

Recurrent Hepatomegaly and Transient Alteration of Liver Functions in an Adolescent with Diabetic Acidosis

* Department of Pediatrics, University of Chicago College of Medicine, Chicago, III. ** Departments of Pediatrics and Biochemistry, University of Florida College of Medicine, Gainesville, Fla. 32601. Correspondence to Dr. Rennert. Supported in part by the Developmental Physiology training grant Tl-HD-0054; the NIH undergraduate training grant 2T1-HE5108 ; and General Research Support grant 623. DIABETES mellitus S is associated with

Echocardiogram in mitral-aortic atresia: False identification of the ventricular septum and left ventricle

SummaryM-mode echocardiograms were correlated with cardiac anatomy in six newborn infants who had autopsy-confirmed mitral-aortic atresia. Echoes from the mitral valve or the aortic valve were not identified. An echo resembling that from the ventricular septum was recorded posterior to the tricuspid valve in all six infants. This echo was separated from the posterior ventricular wall echo by a space that varied in width from 3 to 8 mm. In two infants, the echo was continuous with that from the posterior aspect of the aortic root area and in all six infants displayed an anterior systolic motion pattern. Autopsy demonstrated that in every case the left ventricle was minute and was located superiorly in the wall of the right ventricle; in life, the transducer beam would not have traversed the left ventricle. The right ventricle was enlarged in every case and had prominent trabeculations of the septal band that created large anatomic spaces within the right ventricle.This study suggests that echoes previously thought to represent the left ventricle and ventricular septum in infants with mitral-aortic atresia do not represent these structures and are possibly created by the unusual right ventricular anatomy. Recognition of this false-positive finding may be useful in the interpretation of echocardiograms of other lesions in which there are abnormalities of the aortic or mitral valve, especially if there is a dominant right ventricle.