Differential vasorelaxant effects of levcromakalim and P1060 in the isolated KCl- and RbCl-precontracted human saphenous vein: possible involvement of intracellular Ca2+ stores.

The influence of rubidium-substituted physiological salt solution (Rb-PSS) on the relaxant effects of K+ channel openers was investigated in the human saphenous vein. In tissues precontracted with 20 mM KCl (in K-PSS) levcromakalim and P1060 produced complete, sustained relaxations. However, in Rb-PSS (containing 20 mM RbCl) these effects were inhibited and, although complete relaxations still occurred, were transient. When caffeine was applied at the beginning of this fade of levcromakalim-induced relaxation in Rb-PSS its contractile effect was potentiated. Similarly, the contraction to noradrenaline was potentiated when applied at the beginning of this fade of levcromakalim-induced relaxation, whereas this response was attenuated in control tissues bathed in 20 mM KCl (in K-PSS). Our results show that the relaxant effects of K+ channel openers in human saphenous vein are inhibited in Rb-PSS, in agreement with previous studies in animal tissue, and suggest that an increased Ca2+ uptake into intracellular stores may be contributory to vasorelaxation.

[Intrapericardial lipoma]. / Lipoma intrapericárdico.

A 27 year-old female patient presented with atypical chest pain. 2-D echocardiogram and thorax computed tomography revealed intrapericardial tumor. The patient was operated on for removal of the tumor, which turned out to be two isolated lipomas. The patient had a rapid postoperative recuperation.

[Surgical treatment of high-risk valvar endocarditis]. / Tratamento cirúrgico da endocardite valvar de alto risco.

The authors have studied the immediate and long term outcome of surgical treatment of acute phase infective endocarditis in a group of 33 high risk patients with valvular heart disease. The age varied from 2 to 68 years, 18 patients were male and 22 were of the white race. The aortic valve was the most frequently involved (18/54.5%), followed by mitral valve (13/39.3%), and tricuspid valve (2/6.0%). Twenty-four patients (72.7%) were in functional class III and seven (21.0%) in functional class IV. The noninvasive studies in those patients revealed 13 cases (39.4%) with normal cardiac size. The EKG was abnormal in 27 cases (81.8%) mostly with left atrial and ventricular hypertrophy. The echocardiogram revealed the presence of vegetations in 27 patients (81.8%) and the blood cultures were positive in 24 cases (72.7%). All patients were treated with antibiotics. The pathologic analysis revealed the presence of vegetations in 94% and structural alterations in 16.5%. Twenty-one patients had heart valve replacement with mechanical prosthesis (63.6%), 11 (33.3%) had bioprosthesis and one had tricuspid excision without replacement (3.0%). The hospital mortality was 12% and the late mortality 3%. Three deaths occurred in patients who had prolonged clinical treatment (more than 35 days) and one patient died of severe fungal endocarditis. The follow-up of the remaining 26 patients varied from 1 to 596 weeks (mean 183) demonstrating important clinical improvement and a normally functioning valve prosthesis. All patients remained in functional class I or II. The analysis of our data indicates that surgical treatment is the best option for high risk endocarditis and should be undertaken earlier in all patients in this group.

A new technique for repair of aortic coarctation. Subclavian flap aortoplasty with preservation of arterial blood flow to the left arm.

From February 1984 to March 1986, 28 patients underwent a new technique of coarctation repair. This technique consists of a complete mobilization of the left subclavian artery extended to the origin of its first branches. The aorta need not be extensively mobilized and the intercostal arteries are individually controlled with snares. After all the proper clamping, the left subclavian artery is detached from the aorta at its origin and is opened longitudinally on its posterior aspect. The anterior wall of the aorta is then incised, beginning with the opening at the origin of the left subclavian artery and extending distally to the descending aorta 12 to 15 mm past the coarctation. The coarctation membrane is excised and the ductus is ligated and divided. The opened left subclavian artery, now forming a flap, is pulled down and sutured to the edges of the aorta, widening the coarctation site and also preserving the blood flow to the left arm. The ages of the patients ranged from 2 months to 25 years (mean 4.24 +/- 4.9 years) and their weights ranged from 2.8 to 52 kg (mean: 14.8 +/- 10.0 kg). There were no hospital deaths and the mean follow-up was 9.6 months (+/- 4.9 months). Recatheterization of four patients from 4 to 12 months postoperatively showed adequate correction and strongly suggested normal growth of the aorta at the site of coarctation, as well as preservation of the blood flow through the left subclavian artery. Doppler measurements showed normal flow to the left arm and no gradients through the isthmic area. Our experience indicates that this technique is not only feasible but is the procedure of choice in most cases of discrete isthmic coarctation and in some cases of long narrowing of the isthmus in patients with a wide range of ages and weights.

Anatomia cirúrgica dos tecidos de condução nas cardiopatias congênitas / Surgical anatomy of the conduction system in congenital heart defects

O perigo de lesao do feixe de conducao esta sempre presente na correcao cirurgica das cardiopatias congenitas. E um risco pequeno nos defeitos dos septos atrial e ventricular; ligeiramente maior na tetralogia de Fallot e nos defeitos do septo atrioventricular; tornando-se alto na transposicao das grandes arterias, nos coracoes com valvulas atrioventriculares cavalgadas e consideravelmente elevada na transposicao corrigida (com lesoes associadas) e na septacao dos coracoes com conexao atrioventricular univentricular.Com base na experiencia coletiva dos autores, os tecidos de conducao do coracao foram estudados na sua disposicao e trajetoria normais e tambem do modo como eles podem ser observados pelo cirurgiao nas varias cardiopatias congenitas. Com relativamente poucas regras a posicao e curso dos tecidos de conducao nos coracoes malformados, podem ser localizados e evitados o traumatismo e lesao dessas estruturas.Na experiencia dos autores a incidencia de disturbios da conducao e praticamente nula na correcao das cardiopatias simples e significativamente baixa nas lesoes complexas

Tratamento cirurgico dos mixomas cardiacos: relato de 15 casos operados e revisao da literatura. / Surgical treatment of cardiac myxomas: report of 15 cases and rewiew of the literature

Os autores analisam 15 casos operados de mixomas cardiacos, sendo 10 casos com mixoma atrial esquerdo, 2 com mixoma atrial direito, 1 de mixoma bi-artrial e 2 de mixoma de ventriculo direito e valva pulmonar. Sao apresentados o quadro clinico observado neste grupo de pacientes, bem como os achados de exame fisico. Chama-se atencao para um ruido pre-sistolico identificado como "tumor plop" no fonocardiograma, que coincide com um entalhe pronunciando na curva ascendente da contracao isometrica registrada no apexcardiograma de alguns pacientes. A ecocardiografia se mostrou diagnostica em 100% dos casos em que foi realizada. A cineangiografia se mostrou um exame de grande valia na deteccao desses tumores, tendo evidenciado o tumor em 84% dos casos estudados. Todos os pacientes foram operados com auxilio de circulacao extracorporea. Sao apresentados detalhes da tecnica de exerese desses tumores. Os resultados operatorios foram bons, com uma taxa de sobrevivencia de 93% num periodo de 6 meses. Houve recorrencia do tumor em 1 paciente com mixoma de ventriculo direito