Volume 16 - Número 2

Traditionally, guidelines are developed by physicians to improve quality of health care, to provide practitioners with valuable medical information and to improve objectivity in medical decision making. Determinant aspects of good guidelines, mainly, development methods, discussing, applicability factors such as costs, ethical and legal implications are approached in this article. Keywords: Guidelines; Clinical practice recommendations; Medical ethics

Introduction: The trend in Brazil of erroneously delaying myocardial revascularization in the elderly determined this study. Three hundred consecutive elderly patients (mean age: 73.92, standard deviation: 3.32). Material and Methods: Between October 1992 and July 1995, 361 consecutive patients underwent isolated coronary artery bypass grafting, of whom 111 (30.7%) were females and 250 (69.35) males. There were 128 (35.5%) diabetic patients and 128 (36.7%) were in NYHA III/IV. Univariate analysis perioperatory of 19 factors followed by multivariate logistic regression analysis of the significant variables (p < 0.005) were done. Results: Major complication occurred in 178 (49.3%) and were independent predictors of operative morbidity: Diabetes mellitus, NYHA functional classification, urgent cases and DP2. There were 33 (9.1 %) in hospital deaths, and diabetes mellitus, NYHA functional classification, unstable preoperative angina and cerebral vascular accident, renal failure, infection and insufficiency respiratory failure were independent predictors of operative mortality. Conclusion: The coronary artery bypass grafting is possible in elderly patients with a favorable outcome, especially when done in patients with normal to moderately depressed left ventricular function. Keywords: Coronary disease, surgery; Myocardial revascularization, mortality; Hospital mortality; Myocardial revascularization, aged

Objective: The aim of this study was to evaluate the possibility of excision of the greater saphenous vein through the minimal invasive technique, assessing its morphologic quality and the early complications in the leg wound. Material And Methods: From July to November/1999, 46 patients received aortocoronary saphenous vein bypass graft. A miniincision was made, the vein was identified and gently dissected out with a special retractor, with a long and narrow blade. The samples of the vein were sent to histological analysis. Taking into accounts the presence or absence of the risk factors (female sex, anemia, obesity, peripheral vascular disease and diabetes mellitus) the patients were divided into two groups. The wounds were inspected, looking for majors and minor wound complications. Results: The average number of incisions was 2.3, the average length was 3.5 cm, and the average of all incision length was 7.3 cm. The average length of vein harvested was 34.1 cm. The mean duration of the procedure was 28.7 minutes. Minor leg wound complications occurred in 5 (10.8%) patients and the most common problem was local hematoma (6.5%). There were no major complications. The macroscopically evaluation showed two tears but the correction was possible. Histological study showed that vascular integrity was maintained and there was no significant endothelial damage. Conclusions: It was possible to harvesting satisfactory length of the vein through minimally invasive technique. This technique does not compromise the morphological quality of the vein graft. A low incidence of leg wound complications was observed, independently of the risk factors. These initial results suggest that this technique can be satisfactorily used for harvesting the greater saphenous vein. However, the long-term results still remain to be determined. Keywords: Myocardial revascularization; Cardiac surgical procedures, methods; Saphenous vein, surgery, methods; Surgical procedures minimally invasive; Saphenous vein, transplantation

Objective: We present a group of patients with end stage ischemic cardiomyophaty, operated with a combined procedure, involving myocardial revascularization, mitral valve anuloplasty and ventriculoplasty. Material and Methods: Twenty seven patients, 22 males, whose mean age was 57.8 years. The majority were in NYHA classes III and IV and had a mean ejection fraction of 15%. Eight patients had IABP inserted preoperatively. CPB, temperature 32° C and warm blood cardioplegia. Twenty-six received 74 grafts (3.1 per patient). 10 had Mitral anuloplasty and 4 Mitral and Tricuspid. Two cases had plication of the LV and 18 DOR procedure. The mean X-clamp time 59m and CPB time 145m. Ten patients came off Bypass on IABP and 25 required inotropic support. Results: There was no theatre mortality. Mean ventilation time 31.7h and mean ICU time 65.7h. Three patients required reventilation, 2 reexploration for bleeding, 8 developed AF and 1 had a stroke. The mean hospital stay was 13 days and 6 patients (22.2%) died in hospital. The main cause of death was low cardiac output syndrome. The minimal follow-up was 10 months and the maximum was 47 months (mean 20.7 months). Two patients died on this period. Nineteen patients were followed-up. Nineteen patients are alive (70.3%). fifteen are in NYHA class I, 2 in class II and 2 in class III. None had MI. Five patients were readmitted. The reasons for admissions were in 2 cases for AF, 2 cases angina and in 3 patients CHF. Conclusion: The cardiac surgical remodeling has high hospital mortality, but acceptable morbidity and reasonable hospital stay. The median term survival is also very acceptable giving the patients a better clinical status. Keywords: Cardiac surgical procedures, methods; Myocardial ischemia, surgical

Objective: The aim of this study is to debate the current status and justification for continued use of stentless valves, outlining the clinical results with the CryoLife-O'Brien composite porcine stentless valveT (CLOB). Material And Methods: Between December 1992 and February 2000, 307 patients underwent aortic valve replacement with a CLOB valve. The mean age was 73 years (range 59-89 years with 16% being 80 years and over). All patients were assessed clinically and by echocardiography postoperatively at 6 days, 6 months, 12 months and yearly thereafter. Results: The hospital mortality was 1.3% (4 valve-unrelated cases). Late mortality occurred with 28 patients (9.2%), of which only 2 were valve-related (late endocarditis). Morbid events have included 2(0.6%) perioperative strokes, 2 (0.6%) perivalvar leaks, 6 (1.9%) endocarditis and 1 (0.3%) structural deterioration. Reoperation was required in 6 patients (1.9%): 3 for endocarditis, 2 for perivalvar leak and 1 for structural deterioration. Serial echocardiography demonstrated a mean gradient of 7mmHg with a very low incidence of trivial incompetence on Doppler, and significant left ventricular hypertrophic regression (p=0.05). Conclusion: Stentless valves have produced excellent early and mid-term results. However, surveillance is required to determine the durability at 10 to 12 years, a time when stented porcine valves begin to show failure from structural deterioration. Keywords: Heart valve prosthesis; Heart valve prosthesis implantation, methods

Objective: To determine the frequency of reversion of atrial fibrillation (AF) to sinus rhythm (SR) following surgical treatment of patients with mitral stenosis (MS) and identify likely favourable or unfavourable factors to this event. Material and Methods: Retrospective case control study, analysing 53 patients with MS, without other valvar diseases, undergoing surgical correction. The baseline characteristics of the studied population were: women: 71.7%; mean age: 42.4 years; functional class III: 67.9%; mean mitral valve area: 0.92 cm2; mean left atrial size: 56.0 mm; rhythm before the surgery: SR: 51.0% and AF: 49.0%. Patients were divided in two groups according to their late postoperative rhythm: group I included the patients with SR after the surgery and group II were formed by those with AF in the postoperative period. Results: Ten (18.9%) patients out of all patients; 38.5% in respect to those with AF presented reversion of AF to SR and 2 of them (3.8% out off all patients; 7.4% out of those with SR) presented degeneration of rhythm from SR to AF. There was statistically significant difference (p < 0.05) between the groups only in respect to variable age (p = 0.0456). Conclusions: The MS correction surgery presents unsatisfactory results in respect to reversion from AF to SR, suggesting the necessity of another associated surgical proceeding to restore the SR. Many studies tried to identify the predisposing factors to the permanence or to the development of AF after the surgery, but they got contradictory results. In the present study, only the variable advanced age presented association with AF. Keywords: Mitral valve stenosis, surgery; Atrial fibrillation, physiopathology; Heart rate, physiology

Introduction: The concept of intraluminal prosthesis was introduced by CARREL, in 1912. In 1978, DUREAU & ABLASA described the first case of type A acute aortic dissection treated with intraluminal prosthesis. This prosthesis was used in the eighties by several groups with good results. Several reports of complications (migration, embolism, stenosis, pseudoaneurysms formation) made the surgical groups lose the enthusiasm with that technique. Objective: To evaluate the sutureless anastomosis using the intraluminal prosthesis in the treatment of type A acute aortic dissection. Material and Methods: During the period from July/1996 to November/1999, 64 patients with the diagnosis of type A acute aortic dissection were operated in our Service. In all the cases we used the intraluminal ring as the technique of suture. The average of age was of 56.3 years, and 89% of the patients were males. All the patients had systemic hypertension. In 26 patients we used only the intraluminal anastomosis. The proximal ring was placed above the coronary ostium and the distal ring was positioned close to the origin of the inominate artery. The aorta cross clamping time in these patients was 9 minutes, and the extracorporeal circulation average of time was 26 minutes. Only in 1 case there was a rupture of the ligature on the proximal ring, when we accomplished a radical surgery (Bentall-DeBonno), maintaining the distal ring. In 23 patients we did the aortoplasty and used a double patch of Dacron to prepare the aortic root, using the intraluminal ring in the distal anastomosis. We operated on the aortic arch of 8 patients (without total circulatory arrest, due to selective perfusion of the right subclavian artery). The replacement of the aortic valve was necessary in just 6 patients. The global mortality was of 10.3% and there was no death among the patients which it was possible the treatment with the double ring. As the postoperative evaluation of these patients the echocardiography and the aortography were made. We did not observe pseudoaneurysm formation or migration and the maximum gradient was of 16 mmHg. Conclusion: The employment of the intraluminal prosthesis in the treatment of the type A acute aortic dissection, provides us fast, safe and haemostatic anastomosis, reducing the mortality. In a medium term follow-up we found no complication related to the employment of the intraluminal ring. Keywords: Aneurysm, dissecting, surgery; Aortic aneurysm, surgery; Heart valve prosthesis implantation, methods

Objective: To evaluate the incidence of infection, the etiological agents, to present the clinical aspects and the surgical morbi-mortality in patients who underwent cardiac transplant at Federal University of São Paulo. Material and Methods: From November 1966 to June 1998, a total of 97 patients were operated by the UNIFESP Cardiovascular Surgery team and survived longer than 1 week after the transplantation and were studied retrospectively as far as infections. The age of the patients ranged from 3 to 63 years (average 44.4 ± 13 years). Most of the patients had dilated myocardiopathy (46), or Chagas (24) or ischemis (23). The follow up ranged from 0.33 to 119 months (36 ± 30.7 months) Results: Of the 97 patients, 16 (16.4%) had infection as the main cause of death, followed by rejection in 10 (10.3%). The causes of infection were: bacterial sepsis in 6 patients, pneumonia in 6, intra-abdominal infection in 2, toxoplasmosis in 1 and cytomegalovirus infection in 1. There were 142 infection episodes, bacterial 76 (52.5%), viral 34 (28.8%), fungi 20 (17.5%) and protozoa 12 (12.4%). There were 8 episodes of the reactivation were treated successfully with alopurinol. Conclusions: Our data showed the predominance of bacterial infections as the cause of most mortality. In transplanted patients suffering from Chagas´disease, the reactivation of the disease may be adequately controlled by means of alopurinol. Such data serve as orientation in our community for our programs of transplants, since they show particular aspects of our enviroment. Keywords: Heart transplantation, infection; Heart transplantation, mortality; Heart transplantation, adverse effects; Infection, epidemiology; Infection, etiology; Infection, mortality

Material and Methods: From August/ 1991 to February/ 2000, 35 orthotopic heart transplants were performed at the Heart Institute of Pernambuco. There were 29 male and 6 female patients ranging in age from 15 to 69 years (mean: 46.9 yr.). Recipient diagnoses included ischemic cardiomyopathy in 18, idiopatic dilated cardiomyopathy in 13, mixomatous disease in 2, rheumatic valvar disease in 1 and Chagas` disease in 1. All were in the final stage of heart failure (functional class III or IV of the New York Heart Association) and the ejection fraction ranged from 16 to 27% (mean: 20.9 ± 2.9). Seventeen (48.5%) patients had had previous cardiac operations. The classical surgical technique described by Lower and Shumway, in 1960, was used in all cases. Mean graft ischemic time was 91 ± 21 minutes (ranged from 60 to 180 minutes). Results: There were 7 (20%) deaths in the early postoperative period. Non-fatal postoperative complications occurred in other 13 patients including 5 episodes of rejection. Mean follow-up period of the 28 survivors was 31.2 months (ranged from 1 to 68 mo.) There were 14 late deaths owing to rejection (4), infection (4), graft coronary artery disease (2), chronic renal failure (2) and sudden death (2). The actuarial survival estimated is 70% at 1 year and 30% at 5 years. Conclusion: It is concluded that cardiac transplantation program is feasible in our community but poorer results in comparison to international experience should be expected owing to social problems of the recipient population. Keywords: Heart transplantation; Heart diseases, surgery

Introduction: In surgical procedures, with cardiopulmonary bypass, hemorrhagic syndromes during and after pump constitute a major concern and in a great number of cases they are heparin-related, a substance still without substitute. Most authors point out the anticoagulant action of heparin as the main problem in bleeding situations and research is developing on antifibrinolytic or platelet-like- drugs to try to substitute for usual heparin. Experience with low-molecular weight heparin, without anticoagulant properties, in cardiopulmonary bypass, was disastrous. High dosage was accompanied by high tube drainage suggesting that postoperative bleeding does not happen just because of the anticoagulant effect of heparin. Material and Methods: Believing in the vascular component of hemostasis and that low-molecular weight heparin non-neutralized by protamin is responsible for the paralysis of small vessels during and after cardiopulmonary bypass surgery, we isolated a high-molecular weight heparin ( modal weight of 25.000 Daltons) to be tested "in vitro" and "in vivo". Results: Its specific anticoagulant activity, by mass, was superior to usual heparin ( modal weight of 15.000 Daltons) "in vitro" (273 ui/mg against 181 ui/mg, respectively) as "in vivo", in dogs, utilizing cardiopulmonary bypass and measuring its activity by activated clotting time, APTT and heparin blood levels. In the experimental laboratory the half-life of usual heparin was of 60 minutes, while for high-molecular weight heparin was above 90 minutes. Conclusion: We believe that this unprecedented experience will lead to its future use in "anima nobile" to further test its neutralization by protamin as well as to confirm the decreased prevalence of bleeding phenomena with its use. Keywords: Heparin, therapeutic use; Anticoagulants, therapeutic use; Extracorporeal circulation; Anticoagulants, chemistry; Heparin, chemistry

The association of bilateral diaphragmatic paralysis and scapular girdle paralysis is a rare complication after aortic aneurysm correction. Such a complication induces to a severe form of hypercapnic respiratory failure in which the success of weaning from mechanical ventilation depends on the capacity of remaining respiratory muscles to compensate extra respiratory work load. Intensive respiratory physiotherapy with muscle training, hydroelectrolityc inbalances correction, treatment of ventilation associated infections and a well planned nutritional support were essential to the successful weaning of mechanical ventilation. Keywords: Respiratory paralysis, etiology; Cardiac surgical procedures, adverse effects; Aortic aneurysm, surgery; Phrenic nerve; Scapula; Brachial plexus; Respiratory paralysis, therapy