Munir Ebaid

Circulating platelet aggregates indicative of in vivo platelet activation in pulmonary hypertension

The authors investigated the existence of circulating cellular aggregates in 12 patients with moderate to severe pulmonary hypertension, using scanning elec tron microscopy. Peripheral venous blood was collected in the presence of 11.5 mM buffered ethylenediaminetetraacetic acid, in order to disperse freshly formed disaggregable aggregates. Irreversible aggregates represented by plate let clusters and/or platelet attachment to either leukocytes or red cells were identified in 7 patients with pulmonary hypertension. Endogenous platelet acti vation was further confirmed by a significant increase in plasma levels of beta- thromboglobulin in comparison with controls (33.8 ± 14.1 vs 22.7 ± 11.5 ng/mL respectively, p < 0.025). The presence of irreversible aggregates in the blood stream strongly suggests that cell-cell interactions actually occur in vivo in these patients. If so, therapeutic measures aimed at preventing in situ thrombosis and its consequences may be beneficial in this disorder.

Intraventricular repair of double-outlet right ventricle with noncommitted ventricular septal defect: Advantages of multiple patches

OBJECTIVE The objective of this paper is to report our experience with biventricular repair of double-outlet right ventricle with noncommitted ventricular septal defect by means of multiple patches that simplify and render feasible the intraventricular correction of this complex anomaly. METHODS From April 1987 to April 1999, in 18 patients with double-outlet right ventricle and noncommitted ventricular septal defect, a technical modification that used multiple patches of bovine pericardium was used to construct an intraventricular tunnel connecting the left ventricle to the aorta. Ages ranged from 2 months to 13 years (mean age 4.73 +/- 3.41 years). RESULTS The early mortality was of 11.1% (2 patients). Surviving patients were followed up for a mean of 2.65 years. Three late deaths (16.6%) occurred: 5 months, 7 months, and 7 months after the operation. All but 1 patient are in New York Heart Association class I. CONCLUSION The use of multiple patches for biventricular correction of this anomaly simplifies and renders feasible the intraventricular repair in cases in which the 1-patch technique was deemed impossible.

Evolutional aspects of children and adolescents with surgically corrected aortic coarctation: clinical, echocardiographic, and magnetic resonance image analysis of 113 patients

OBJECTIVE The goals of this study were to determine the prevalence of hypertension and recoarctation in operated children and teenagers and to integrate clinical and imaging technique data. METHODS One hundred thirteen infants and children (ages 14 years or less) were retrospectively divided into 3 groups according to the age at operation and the surgical technique: 79 underwent resection with end-to-end anastomosis; 14 had patch enlargement; 13 had subclavian flap aortoplasty; and 7 had other techniques performed. The mean age at operation was 3.95 +/- 4.17 years and the mean follow-up period was 4.62 +/- 4.90 years. Each patient was clinically examined and Doppler echocardiography was performed in 112 patients. Sixty-six patients underwent magnetic resonance imaging. Diameters of aortic arch were measured at 4 levels; the ratios between each one and descendent aorta diameters were calculated. Qualitative variables and associations were studied by Fisher exact test or chi-squared test. Comparisons of measurements in different groups were performed using variance analysis, with tests of selective contrasts (nonparametric tests). The level of statistical significance was <.05. RESULTS The prevalence of hypertension and recoarctation was 38% and 14%, respectively. No statistical difference was found among the age groups. In 65 patients who underwent magnetic resonance imaging, the transverse aortic arch was hypoplastic in 31 (47%) patients; 41 (63%) had stenosis at the site of anastomosis (ratio < 0.9). CONCLUSION Hypoplasia of transverse aortic arch was highly prevalent. These data suggest that hypoplastic aortic arch should be corrected concomitantly with coarctation.

Uhl's anomaly. Differential diagnosis and indication for cardiac transplantation in an infant

We report the case of an 8-month-old female infant with Uhls anomaly, who underwent successful cardiac transplantation. The clinical findings, complementary laboratory tests, anatomic findings, and differential diagnosis of the anomaly are discussed.

Effects of Low Doses of Inhaled Nitric Oxide Combined with Oxygen for the Evaluation of Pulmonary Vascular Reactivity in Patients with Pulmonary Hypertension

The purpose of this study was to evaluate the hemodynamic effects of inhaled nitric oxide in oxygen (NO + O2) in patients with pulmonary hypertension. Eighteen patients (median age 31.5 months) with pulmonary hypertension inhaled through a mask 100% O2 and 20 parts per million NO + inspired O2 fraction (FiO2) at 0.4. Hemodynamic measurements were made at baseline and after O2 and NO + O2 administration. The pulmonary vascular resistance index decreased after inhalation of O2 and NO + O2 (p = 0.0018 and p = 0.0003, respectively), the decrease being significantly greater after NO + O2 (p = 0.0311). Concerning the transpulmonary pressure gradient, a reduction occurred in values after O2 and NO + O2 inhalation when compared with baseline values (p = 0.0014 and p = 0.0008). In patients with congenital heart disease, an increase occurred in pulmonary blood flow after O2 (p = 0.0089) and NO + O2 (p = 0.0019) compared with baseline values, and an increase also occurred in the pulmonary/systemic blood flow ratio after NO + O2 (p = 0.0017). The main side effect related to NO + O2 was pulmonary congestion in 3 patients. Low doses of NO combined with O2 demonstrated a selective pulmonary vasodilator response in patients with pulmonary hypertension. Despite its use for testing pulmonary reactivity, inhalation of NO + O2 should be carefully administered because of the potential risk of pulmonary congestion.

Aortopulmonary window. Clinical and surgical assessment of 18 cases

OBJECTIVE Aortopulmonary window (APW) is an uncommon congenital malformation. Its clinical presentation is dependent on the size of the defect and on the associated lesions. We evaluated our experience with this anomaly and compared it with 296 cases reported in the literature. METHODS Retrospective study of 18 patients diagnosed as having APW (age range from 13 days to 31 years, 13 (72.2%) females), divided into two groups: Group A (GA): 10 patients with isolated APW, and Group B (GB): 8 patients with associated lesions. RESULTS Heart failure occurred in 14 patients, and cyanosis in 3:2 from GB (tetralogy of Fallot--TF, and double outlet right ventricle--DORV), and one from GA with pulmonary hypertension. In 5 patients from GA the diagnosis of mitral regurgitation was made based on a systolic murmur and LV hypertrophy on the EKG. In GB, clinical findings were determined by the associated defect. Diagnosis was established by echocardiography in 11 (61.2%) of the patients. In 3 patients, a wrong diagnosis of mitral regurgitation was made, in 1 a patent ductus arteriosus was diagnosed and in 3 others, the diagnosis of APW was masked by other important associated defects (2 cases of DORV and 1 case of TF). The diagnosis was made by catheterization in 3 (16.6%) patients, by surgery in 3 (16.6%) and by necropsy in 1 (5.5%). Corrective surgery was performed in 14 (77.7%) patients, with one immediate death and good long-term follow-up in the remaining patients. CONCLUSION APW can be confused with other defects. Clinical findings, associated with an adequate echocardiogram can provide the information for the correct diagnosis.

Coexistence of divided left atrium (cor triatriatum) and tetralogy of Fallot

The association of a partitioned left atrium (cor triatriatum) and tetralogy of Fallot has been reported a few times in the literature. In all of these cases, there was no clinical evidence of an obstructive lesion in the left heart, raising difficulties in establishing the proper diagnosis. We call attention to this rare combination of anomalies and to the particular morphological presentation of the dividing atrial shelf, which was partially formed by the wall of the left superior caval vein.

The vectorcardiogram in dorsal or posterior myocardial infarction.

Abstract The vectorcardiograms of twenty-five patients with dorsal infarction of the heart were studied. These infarctions were classified into four groups as follows, all of which showed an increase of the R wave in the B (anterior-posterior) component of Grishmans cube system: 1. 1. Strictly dorsal infarction, showing only an increase of the R wave in the B component. In this group were three cases, including one complicated by complete right bundle branch block. 2. 2. Inferodorsal infarction, showing pathologic Q waves in the C (superior-inferior) component. There were five cases in this class. 3. 3. Laterodorsal infarction, showing abnormal Q waves in the A (right-left) component. Eight cases were placed in this class. 4. 4. Inferolaterodorsal infarction, with abnormal Q waves in the A and C components. There were nine cases, including two complicated by complete right bundle branch block, in this group. The vectorcardiograms of these cases showed increased magnitude and forward orientation of the initial portions (0.02 second) of the ventricular activation loop. These initial portions frequently had a higher speed of inscription due to the absence of opposing forces. The necrotic areas in the dorsal wall which should undergo early depolarization were not activated at the same time; therefore, no electrical forces were produced in those areas. In dorsal infarction, the rotation of the QRSsE in the horizontal plane was predominantly counterclockwise. This, together with the direction of predominant forces forward (average 0.048 second) and the orientation of the TsE in the same direction, facilitates the diagnosis of dorsal infarction in those cases in which a tall R wave in the right precordial leads might suggest right ventricular hypertrophy. In eleven cases a certain delay of inscription and deformity in the morphology of the terminal portions of the QRS loop was observed.

Choreoathetosis after cardiac surgery with hypothermia and extracorporeal circulation

Eleven children, 4-48 months old, with congenital cyanotic heart defects developed choreoathetoid movements 2-12 days after cardiac surgery with hypothermia and extracorporeal circulation (ECC). The abnormal movements mainly involved the limbs, facial musculature, and tongue, leading to a severe dysphagia. The symptoms had an acute onset, after a period of apparent neurologic normality, and had a variable outcome. Of the nine children that survive, three had abnormal movements when last seen (41 days to 12 months of follow-up). The other six children had a complete regression of the choreoathetoid movements 1-4 weeks after onset. No specific finding was observed in the CT scans, cerebrospinal fluid examination, or EEG that could be related to the abnormal movements. Symptomatic therapy with haloperidol with or without benzodiazepines led to symptomatic improvement in six children, although there was no evidence that this treatment modified the evolution of the disease. The authors conclude that the choreoathetoid syndrome after cardiac surgery with deep hypothermia and ECC is an ill-defined entity requiring additional study to better understand its pathogenesis so that preventive measures can be taken to avoid a condition that can lead to permanent and incapacitating neurologic sequelae.

Correlation between gallium-67 imaging and endomyocardial biopsy in children with severe dilated cardiomyopathy

Fourty-four patients (aged 10 months to 15 years) were assessed in a double-blind study to observe the correlation between myocardial uptake of 67-gallium and endomyocardial biopsy in the detection of moderate to severe myocardial inflammation. The sensitivity and specificity of gallium-67 imaging were 87 and 81%, respectively. Based on these findings, immunosuppressive therapy can be assigned to children with dilated cardiomyopathy and positive myocardial uptake, since moderate and severe myocardial inflammation may be detected by this non-invasive method.