Hypertrophic obstructive cardiomyopathy in pediatric patients: results of surgical treatment

Between April 1975 and May 1995, 25 pediatric patients on one hospital service underwent extended left ventricular septal myectomy because of hypertrophic obstructive cardiomyopathy. Ages ranged from 2 months to 20 years (mean, 11.2 years). Seventeen patients had moderate to severe mitral valve insufficiency. Medical therapy had failed in all patients and one patient had undergone dual-chamber pacemaker implantation without improvement. Left ventricular outflow tract gradients ranged from 50 to 154 mm Hg (mean, 99.9 +/- 25.2). Concomitant cardiac procedures included mitral valve repair (n = 2), automatic implantable cardioverter defibrillator implantation (n = 1), and closure of atrial septal defect (n = 1). Intraoperative premyectomy left ventricular outflow tract gradients ranged from 20 to 117 mm Hg (mean, 60.4 + 26.2) and postmyectomy gradients ranged from 0 to 20 mm Hg (mean, 6.6 +/- 5.9). Postmyectomy mitral insufficiency was reduced to a regurgitant fraction of 0% to 12%, and no patient required mitral valve replacement. One patient required a pacemaker because of complete heart block; on subsequent follow-up, normal sinus rhythm had returned. There was no early mortality and no instance of aortic or mitral valve injury or ventricular septal defect. Follow-up ranged from 10 months to 20 years (mean, 6.4 years). There were no late deaths. Left ventricular outflow tract gradients by echocardiography were a mean of 14.2 mm Hg with a median of 5.0 mm Hg. All patients had normal sinus rhythm. Reoperation because of recurrent left ventricular outflow tract obstruction was necessary in two patients at 3.2 years and 12.4 years after initial myectomy, respectively. All patients but one have New York Heart Association class I or II function. We conclude that extended septal myectomy is a safe and effective means of relieving cardiac symptoms and left ventricular outflow tract obstruction in pediatric patients with severe hypertrophic obstructive cardiomyopathy unresponsive to medical management, and late survivorship compares favorably with the natural history of the disease.     

Choice of treatment of destructive pancreatitis and its complications

Choice of a proper method of treatment of complicated acute pancreatitis remains indefinite. The results of treatment of 130 patients with acute destructive pancreatitis complicated with pancreatic pseudocysts have been analysed. The authors formulate individual indications to minor surgery under the ultrasound control. The classical type of surgery was used only in patients with calculous pancreatitis complicated with pseudocysts (14). In other patients various types of transcutaneous ultrasound controlled procedures were used. Pilot experience of placing cystoduodenoanastomosis under ultrasound endoscopic control is described. Letal outcomes were absent. The rate of recurrence in external drainage was 10, 5%; there were no cases of recurrence in internal drainage of pseudocysts. The period of long-term follow-up was 58 months.     

In vitro studies of laser fluorescence for detection and quantification of mineral loss from dental caries

The paper described three previously undetected effects, due to biases and non-independence, that can arise in statistical tests for associations between character states in cross-species data. One kind, which we call the family problem, is general to all known methods. In phytogenetic data, the ancestral character state from which changes occur, or below which variation is found, is likely to be the same for many regions of the tree. The family problem interacts with two kinds of non-independence that arise because of the methods of reconstruction of character states that existing tests use. Different kinds of non-independence arise in methods that reconstruct joint, or single, character states, respectively. Methods, like Ridley's (1983), that work with joint character states suffer from the problem that a character state cannot change to itself with parsimony. Other methods that work with single character states suffer from the problem that within a locally variable region of the tree it is more likely with null data that there will be two single changes in the two characters in separate branches than one double change in both; associations opposite to the locally ancestral state are therefore likely to be found in more than 50% of the variable regions. In real data sets, the family problem acts to spotlight the other kinds of bias: if the family problem is large the bias in tests due to the way they reconstruct characters will be large, whereas if it is small, the local biases tend to cancel and disappear in the aggregate.     

Cell-mediated immunity in atherosclerosis

Immunocompetent cells infiltrate atherosclerotic plaques of all stages. Plaque-infiltrating T-cells recognize oxidized LDL and heat shock proteins and this elicits antibody responses that have been proposed as markers of disease activity. Cytokines secreted by activated T-cells may control macrophage activation, scavenger receptor expression and metalloproteinase secretion. Furthermore, cytokines secreted by T-cells and macrophages modulate smooth muscle proliferation, nitric oxide production and apoptosis, and induce endothelial activation. However, both positive and negative signals, as well as feedback loops, may be induced because of the complexity of the immune system. The possibility that some of these signals may be protective against atherosclerosis is currently under investigation in several laboratories. Recent studies in experimental animals show that immunomodulation affects the development of plaques and that immunization with oxidized LDL can inhibit lesion formation. This review provides a brief overview of cellular immunology and an analysis of its potential role in atherogenesis.     

Pediatric and psychiatric comorbidity. Part I: The future of consultation-liaison psychiatry

This study was conducted to investigate the influence of high-frequency aircraft noise on the function of the auditory system of school-age children. A total of 228 students attending a school near an airport (school A) and 151 students attending a school far from an airport (school B) were analyzed. Audiometry and brainstem auditory evoked potential (BAEP) detection were performed in all subjects to evaluate cochlear and retrocochlear function. The results of audiometry indicated that hearing ability was significantly worse in the children of school A, which was located under the flight paths. The values of pure tone average, high pure tone average, and threshold at 4 kHz were all higher in children who were frequently exposed to aircraft noise. There was no consistent difference in BAEP latencies between the two schools. These results indicate that central transmission is not affected in children who have been exposed to aircraft noise for several years. The results of the present study showed a significant association between aircraft noise exposure and prevalence of noise-induced hearing loss. Although damage to peripheral cochlear organs was confirmed in school-age children, involvement of the central auditory pathway could not be verified.     

The effect of propionyl L-carnitine on skeletal muscle metabolism in renal failure

The effect of propionyl L-carnitine on skeletal muscle metabolism in chronic renal failure. Carnitine deficiency, resulting in defective oxidative ATP synthesis, has been implicated in the myopathy of chronic renal failure. Using 31P magnetic resonance spectroscopy we examined calf muscle metabolism in 10 dialysed patients before and after 8 weeks of propionyl L-carnitine (PLC) 2 g.p.o. daily. Resting phosphocreatine/ATP (4.41 +/- 0.20 [SEM]) decreased to normal control levels on PLC (3.98 +/- 0.14; controls 4.00 +/- 0.06). In contrast, there was no effect of PLC on aerobic and anaerobic metabolism of muscle during or following 2-10 min exercise. The maximal calculated oxidative capacity (Qmax) remained below normal (28 +/- 3 mM/min before and 24 +/- 3 mM/min after PLC; controls 49 +/- 3 mM/min). Qmax correlated positively with hemoglobin concentration ([Hb]) after PLC (p < 0.03). Oxidative capacity assessed by phosphocreatine recovery T significantly improved with PLC administration (0.93 +/- 0.1 to 0.74 +/- 0.08 min) in those patients (n = 6) with [Hb] > 10 g/dl. [Hb] was rate limiting to oxidative metabolism in recovery from exercise but only following treatment with PLC. Patients with anemia or those subjects who use relatively more non-oxidatively synthesized ATP during exercise, do not respond to PLC. Oxidative metabolism did not normalize on PLC suggesting that anemia and carnitine deficiency are not the only causes of mitochondrial dysfunction in renal failure.