Volume 7 - Número 3
ORIGINAL ARTICLE
Tolerance of placenta to normothermic umbilical circulatory arrest
Braz J Cardiovasc Surg 7;
Publish in: 8/2/2025
Elevation of placental vascular resistance (PVR) and depression of fetal gas exchange occurs after fetal cardiopulmonary bypass (CPB). Excluding the placenta from the CPB circuit may protect the placental vasculature from the unwanted stimuli which lead to elevated PVR. To evaluate this approach, 9 isolated in-situ sheep placentas were placed on CPB by cannulating the umbilical vessels, with a mean umbilical artery flow of 214 ml/min/kg. After 30 minutes of stable flow, placental circulation was arrested for 30 minutes, simulating the umbilical vessel clamp time during whole body fetal CPB. Placental circulation was then restored to baseline values. Placental gas exchange and maternal placental blood flow were evaluated before and after arrest. Interruption of blood flow to the placenta for 30 minutes under normothermic conditions does not affect placental function or maternal placental blood flow. It may be possible to exclude the placenta from the circulation during fetal CPB as a mean of eliminating the detrimental effects of CPB on placental gas exchange. This model suggests an alternative way of designing a scheme for clinical fetal CPB which may avoid the negatives effects of CPB on the placenta.
Keywords: fetal cardiopulmonary bypass; fetal surgery; placental function
NE-Tx North East Brazil heart transplant program: current-experience
Braz J Cardiovasc Surg 7;
Publish in: 8/2/2025
The authors report their current clinical experience with the "NE-Tx" program, which covers four different centres, as well as its regional peculiarities. The program was designed to be of low cost and regionally integrated. In the preoperative investigation the social and intellectual level of the recipient and his relationship with family members were assessed. The need to send for an organ from elsewhere was eliminated by providing for the recipient to be transported to the place where the appropriate organ is available. No serous dosages of cyclosporine were used postoperatively, all pacients having been through periodic monitoring of renal funcion. By means of this strategy, seven patients were operated on between 19.07.86 and 01.11.91 in three diferent integrated centres. All were males, with ages ranging from 17 to 50 years. Three (42.8%) of the pacients were suffering from Chagas's disease, two (28.5%) from idiopathic myocardiopathology, one (14.3%) from hipertrophic myocardiopathology and one (14.3%) from rheumatic myocardiopathology. Three (42.8%) pacientes came from different Centres: one from Natal to Recife, another from Maceió to Aracaju and a third from Aracaju to Maceio. Two (28.6%) pacients died: one shortly after surgery from an unknown cause, the other in the late postoperative period from a rejection crisis. Early mortality was 14,3% and late mortality also 14.3%. The remaining five (71.4%) pacients are progressing well, their follow-up ranging from 2 to 48 months. The incidence of infection, rejection and other problems related to the late follow-up is comparable with that of others Centres. The program has proved to be efficient, practical, compatible with our actual situation, and reproduces the results of others experiences.
Keywords: heart transplantation, human; heart transplantation, orthotopic
Valvular surgery in childhood: new trends
Braz J Cardiovasc Surg 7;
Publish in: 8/2/2025
From January 1978 to December 1991, 148 children (age < 15 years) were operated upon on our Service for the first time, to correct defects (rheumatic fever) on the cardiac valves. The material was divided in two times, according to the point of view of the group in an attempt to preserve a great number of valves, in especial in children. Last year 24 children were operated upon in whom mitral valve disease treatment was necessary twenty times, and in aortic valve eight times. In that group, 95% (28% before) surgery on the mitral valve and 62% (20% before) on the aortic valve were conservative procedures. There were neither deaths nor complications and all children have good evolution. We conclude that on rheumatic fever, cardiac valve disease treatment in children must be conservative and the best time for the surgery must be earlier, to avoid valvar disfunction due to disease. We also think that follow up must be effective in order to analyze if different available plastic techniques are better than valve substitution in children with rheumatic fever.
Keywords: heart valves, surgery, children
Left ventricular aneurysm in Chagas' disease: surgical aspects in 29 cases
Braz J Cardiovasc Surg 7;
Publish in: 8/2/2025
During the period between March 1980 and December 1991, 29 patients have been operated upon for removal of left ventricular aneurysms of Chagas' disease ethiology. There were 22 females and 7 males, with ages at operation ranging from 21 to 69 years. All of them had a positive immunologic reaction to Chagas disease; 8 patients presented preoperatively stroke, 8 patients had tiredness associated with heart failure, 8 patients had palpitations and seizures; 5 others presented multiple symptoms. Three patients had artificial pacemakers implanted. The electrocardiogram was abnormal in all cases; half of them had normal chest roentgenograms. Coronary arteriography was normal in all patients. Left ventricular angiogram demonstrated an apical lesion like a "nipple" in 14 cases, a saccular aneurysm in 8 cases, an inferior wall aneurysm in 4 cases, and combined apical and inferior aneurysms in 3 cases. One of the cases of double aneurysms had also severe mitral insufficiency. In 4 patients thrombi were detected in the left ventricular angiogram. There was no hospital mortality. During follow-up we registered a single death and 3 patients progressed to a complete heart block which required pacemaker insertion. Another patient had recurrence of preoperative arrhithmia. We conclude that surgical removal of left ventricular aneurysm associated with Chagas' disease in selected patients is a low mortality procedure, may prevent recurrent thromboembolysm, controls heart failure and may suppress arrhithmias in a significant number of patients.
Keywords: Chagas' disease aneurysms, surgery; aneurysms, left ventricle, surgery
Non-supported mitral annuloplasty technique for treatment of rheumatic mitral insufficiency
Braz J Cardiovasc Surg 7;
Publish in: 8/2/2025
Since 1974 a non-supported mitral annuloplasty technique has been employed for treatment of pure mitral regurgitation (PMR), in a population that was predominantly young and of rheumatic ethnology. An evaluation of late results forms the basis of this report. There were 154 patients operated on for PMR, 55 (36%) male and 99 (64%) female. Mean age was 36 ± 16 (5 to 73) years. Associated lesions were: 47 aortic, 21 tricuspid and 2 ASDs (atrial aptal defects). Cases with concomitant mitral stenosis were not included. Properative functional class was I-II in 19% and III-IV in 81%. The cardiothoracic ratio was 0.61 ± 0.10. All patients were submitted to an unsupported mitral annuloplastic procedure, similar to that described by WOOLER, that consisted in reduction of the mural portion of the annulus obtained with the application of two buttressed mattress sutures at the comissures without compromisse to the width of the septal leaflet. When necessary, additional chordal procedures were performed. No patients received ring or posterior annular support. Residual late systolic murmur was present in 48%. Late complications were: systemic thromboembolism 5.8% (1/3 with aortic prosthesis), infective endocardites 1.3% and pulmonary thromboembolism 0.7%. Postoperative functional class was I-II in 84% and III-IV in 16%. Cardiothoracic ratio was 0.58 ± 0.10. Actuarial probability of late survival was 79.5 ± 5.3% at 10 years and 71.0 ± 7.4% at 14 years. Event free survival was 67.9 ± 8.9% at 10 years and 56.1 ± 11.7% at 14 years. Rheumatic mitral regurgitation can be effectively treated by annuloplasty without prosthetic annular support with late results comparable to those obtained with more complicated procedures. This is particularly important for treatment of children and young patients, specially females at child-bearing age which, in some areas, form a substantial cohort in mitral disease.
Keywords: mitral valve, surgery; valvuloplasty; rheumatic mitral regurgitation
Bidirectional Glenn anastomosis
Braz J Cardiovasc Surg 7;
Publish in: 8/2/2025
The bidirectional Glenn anastomosis has bee used as an effective mean of palliating complex heart defects, in those patients that doesn't meet the necessary criteria for prosecution of an atriopulmonary anastomosis. The surgery consists on anastomosing the superior caval vein (end to side anastomoses), in a way that the venous blood is distributed to both the right and left lungs. Between January and February, 1992, 20 patients have undergone the bidirectional anastomosis at the Instituto Dante Pazzanese de Cardiologia. Eight patients were female. Their ages ranged from 5 months to 8 years (mean age 37.7 months) and their weights ranged from 6.3 to 18.8 kg (means 12.4 kg). The surgical indication was considered primary in 10 cases. There were 8 patients with tricuspid atresia and 3 double inlet ventricles with highly diminished pulmonary blood flow considered not ideal candidates to a complete rapair. The other patients were considered secundary surgical indication. They had previous palliative operations such as systemic pulmonary shunts; pulmonary banding and atrialseptectomy (6 with tricuspid atresia, 3 double inlet ventricle with pulmonary stenosis or banding and 1 double intlet right ventricle with superior inferior ventricle). The surgery was performed with direction of the caval vein to right atrium in 12 cases and by means of cardiopulmonary bypass in 8. During the operation, the patients were monitored with a pulsatile oximeter. The mean preoperative arterial oxygen saturation was 75.5% (range 71 % to 86%) and postoperative 95% (range 91 % to 98%). No hospital death occurred. There was one late death caused by pulmonary infection two months after the surgery. We believe that the bidirectional Glenn anastomosis has its place as a first stage to a complete correction, because it doesn't increase cardiac work and pulmonary vascular resistence and is not associated with pulmonary arterial and anastomotic distortions as Blalock-Taussig does.
Keywords: Glenn bidirectional, surgery of
Aortic aneurysms
Braz J Cardiovasc Surg 7;
Publish in: 8/2/2025
Among 212 patients undergoing operation for aortic aneurysm and aortic dissection between January 1979 and January 1992, 97 were operated on for aneurysms. The aneurysms were localized in: ascending aorta in 46 patients, transverse aortic arch in 8, descending aorta in 8, thoracoabdominal aorta in 8, abdominal (infrarenal) aorta in 21, descending and abdominal aorta in 2, ascending and thoracoabdominal aorta in 2, ascending and descending in 1, ascending, transverse arch and descending aorta in 1. Hospital mortality was 14,4% being 27,7% (5/18) among patients over 70 years old an 11,3% (9/79) among patients under 70 years of age. Our experience suggests that: secondary and tertiary operations, advanced age, associated diseases, respiratory infection and acute renal failure increase early mortality.
Keywords: aneurysms, aortic, surgery
Clinical results with a new "Stentless" aortic bioprosthesis
Braz J Cardiovasc Surg 7;
Publish in: 8/2/2025
From May/1990 to March/1992, 81 "Stentless" porcine bioprosthesis were implanted in the aortic position in three Centers: Biocor Institute (34 patients), University of Torino (31 patients) and Karolinska Hospital (16 patients). The age ranged from 14 to 85 years, with a mean age of 51. There were 48 male patients and 33 femele; the post operative follow-up ranged from 1 to 22 months (mean = 7 months). The main indication was aortic stenosis. There were 5 patients with acute endocarditis of the native aortic valve, with significant hemodynamic impairment, and presence of annular abscesses in 3 of them. All patients were operated on under moderate hypothermia and myocardial protection, with cristalloid cardioplegia. The "Stentless" bioprosthesis was inserted using two layers of a 4-0 Prolene running suture. All patients survived the operation; there were 4 early deaths (4.93%) and one late death secundary to pulmonary embolism (16 th months post. op.). The major hospital complication was complete AV block in 7 patients. All patients are in regular clinical follow-up, including hemodynamic assessment by echodopplercardiography. The preliminary data show an excellent hemodynamic performance of the "Stentless" bioprosthesis.
Keywords: heart valves prosthesis, aortic, surgery
Early extubation ¡n pediatric cardiac surgery: proceedings and results in six years experience
Braz J Cardiovasc Surg 7;
Publish in: 8/2/2025
Of 441 pediatric patients recovering from surgical repair of congenital heart disease, 372 (84%) were extubated in the operating room immediately after the procedure, using a clinical criteria, cutaneous pO2 saturation and pCO2 in exchanged air. Postoperative complications were not correlated with the procedure, and less pulmonary complications were observed. We concluded that most of pediatric patients, including many of those with complex lesions and preoperative pulmonary hipertension, can safely be extubated early cardiac surgery with minimization of pulmonary complications secondary to mechanical ventilation as well as reduced length of ICU and hospitalary stay, minimizing children and parents stress and hospitalary cost.
Keywords: pediatric cardiac surgery, early extubation
HOW TO DO IT
How to do it: low volume backward normal thermic blood cardioplegia
Braz J Cardiovasc Surg 7;
Publish in: 8/2/2025
Keywords: myocardial protection, cardioplegia