Volume 15 - Número 4

OBJECTIVES: During coronary surgery without CPB, exposure of posterior vessels via sternotomy can cause deterioration of cardiac hemodynamics, requiring inotropic drug support. Recent animal experiments demonstrate the hemodynamic benefit of right heart support (RHS) with the A-MED system. The aim of this study is to evaluate the hemodynamic effect of RHS in: restoring hemodynamics, increasing anastomotic exposure and reducing inotropic requirements. MATERIAL AND METHODS: Eleven patients received coronary revascularization with the A-MED RHS device. All had at least 1 circumflex branch bypassed. The anterior wall was systematically bypassed off pump without RHS. The right coronary artery (RCA) and the obtuse coronary artery (OM) were completed utilizing RHS. Mean arterial pressure (MAP), mean pulmonary arterial pressure (PAP), cardiac output (CO) and the average pump flow (APF) were recorded during the OM and RCA bypass. RESULTS: Elective beating heart coronary artery graft (CABG) was successfully accomplished in 11 patients with RHS. Data measurements recorded showed the improved hemodynamic recovery for OM and RCA bypass with RHS. The MAP increased from 44 to 63 mmHg (OM) and from 63 to 81 mmHg (RCA). No device-related patient incidents occurred. All 11 patients were discharged to their homes. CONCLUSIONS: The AMED system as RHS support facilitated coronary bypass without CPB to posterior vessels, restoring hemodynamics, providing better exposure to anastomic sites and apparently reducing the need for inotropic support. Keywords: Myocardial revascularization, methods; Hemodynamics, physiopathology; Extracorporeal circulation; Ventricular function, right, physiology; Heart ventricle; Coronary vessels, surgery; Heart-assist devices

OBJECTIVE: To demonstrate our experience with the myocardial revascularization using the implantation of left internal mammary artery. This procedure was proposed by Vineberg, in 1946. MATERIAL AND METHODS: From August 1994 to September 1998, 10 patients were operated on, all of them had the left internal mammary artery implanted in the anterolateral part of the wall of the left ventricle and all of them had a saphenous vein bypass graft. The age of the patients ranged from 42 years to 73 years with the prevalence of males. All patients had a diffuse and severe coronary artery disease mainly of the interventricular (descending) anterior artery, but with myocardial viability. The indication for internal mammary implantation was made during the procedure, because the techniques as saphenous vein bypass or endarterectomy were not considered applicable to these cases. RESULTS: All the patients were very well in the post operative period; from 45 days to 23 months, coronariography study were performed on nine patients, showing the implanted internal mammary artery arborizing and communicating with the native coronary arteries. CONCLUSION: The internal mammary artery implanted in a viable myocardium should have its place on myocardial revascularization treatment, in selected cases. Nowadays, observing the misinterpretation on the past papers, we can select the patients with appropriate indication for this technique, obtained good results. The Vineberg technique needs more experience to define the evaluation of its real effectiveness. Keywords: Thoracic artery implantation, methods; Myocardial revascularization, methods; Cardiovascular surgical procedure, methods; Cardiac surgical procedures, methods; Coronary vessels, surgery; Thoracic arteries, surgery

OBJECTIVE: To evaluate the evolution up to 15 years of patients who underwent surgical correction of left ventricular aneurysm and to compare the techniques of linear suture and geometric reconstruction. METHODS: We studied 213 patients, of which 166 (77.9%) were men. The mean age was 53.1 years (SD=9.9 years). Of these, 145 (68%) underwent repair using the linear suture technique and 68 (32%) underwent the geometric reconstruction technique. The Kaplan - Meier method was used to evaluate late survival. We evaluated the presence of mural thrombus, in and out of hospital mortality and the possibility of myocardial revascularization in the same procedure. Statistical differences were measured using the Log Rank method for actuarial curves and the nonparametric test in the remaining data compared. RESULTS: Our survival curves after a follow up of 10 years demonstrated that patients submitted to the linear suture and LV geometric reconstruction had a survival of 47.19% (SEM=0.056) and 63,55% (SEM=0.068), respectively, which were not statistically significantly different (p= 0.56). The overall survival in the 2 groups together was 51.34% (SEM=0.0473) at 10 years and 35,77%(SEM=0.0684) at 15 years. The in hospital death was 9.5% for the linear suture and 16.6% for the geometric reconstruction (p=0.17). The removal of LV thrombus was 31.29% and 45.45%, respectively (p=0.07). Revascularization was performed in, 69% of the patients in the linear suture group and 85.3% in the geometric reconstruction group. Comparing patients who were revascularized with those who were not, there was a better survival at 10 years for the first group (p=0.008). CONCLUSIONS: There was no statistically significant difference in the survival of patients who underwent linear suture compared to geometric reconstruction of the LV for aneurysm repair. Our results demonstrated superior survival in those patients who could undergo revascularization in the same procedure. Keywords: Heart ventricle, surgery; Heart aneurysms, surgery; Heart ventricle aneurysm, surgery, comparative study; Heart ventricle aneurysm, surgery, methods; Surgical anastomoses, methods

OBJECTIVE: The authors present the initial results, on the left ventricle (LV) anterior aneurysms' treatment, by the Dor's technique of endoventricular circular patch plasty with septal exclusion. This work was initially based on Hutchins and Bulkley's (1980) concepts of left ventricle geometry and its' geometrical reconstruction, and on those of the circular reduction surgery by Jatene (1984). MATERIAL AND METHODS: Between April and October 1999, we performed six procedures for the surgical correction of LV aneurysms, by Dor's technique. Time between the anterior wall infarct and the surgical procedure varied between 8 days and 10 months, being 3 patients in functional class III, of the NYHA, 2 in class IV and 1 in class I. Four patients were males and the mean age was 58.3 years. On the pre-operative angiographic studies the global ejection fraction varied from 27 to 46% (mean 37.2%), the LV end systolic volume from 64.4 to 135.3 ml (mean 107.9 ml) and the LV end diastolic volume from 132.9 to 236.4 ml (mean 183.8 ml). The procedure was associated with the resection of mural thrombus, in 3 cases, myocardial revascularization in 5 cases, using 10 venous and three arterial grafts (2.2 grafts/patient) and 1 endarterectomy. The anterior wall was revascularized in 9 cases and the lateral and inferior in 2 each. The mean cross clamping and bypass time were, respectively, 44 and 110 minutes. RESULTS: The mean hospital post-operative time was 7.7 days. The patients were followed up for a period of 5 to 31 weeks, being all in functional class I. In 3 cases an angiography was performed, and on the other two a two dimension echocardiogram, to evaluate the global ejection fraction, which varied from 42.5 to 60% (mean 49.4), with an improvement of 32.8%. CONCLUSIONS: The authors believe, with these initial results, that this is another technique for the surgical correction of LV aneurysms with improvement of the LV function and the new geometry. Keywords: Heart ventricle, surgery; Cardiac surgery procedures, methods; Heart aneurysms, surgery; Aneurysm, ventricular, surgery; Heart ventricle, pathology; Heart ventricle, surgery, methods

BACKGROUND: Infective endocarditis is a disease of difficult and multidisciplinar treatment that frequently needs the surgical participation. MATERIAL AND METHODS: Between January 1987 and January 1999, 159 patients were operated on in our Service for infective endocarditis. Male group represented 64.7%. The mean age was 39.2 yr. (2 to 78 yr.) and the mean weight 57.1 kg. The aortic valve was affected most frequently (66 patients), the native valve was affected in 47 cases and the prostheses in 19 (11 bioprostheses and 8 mechanic valves). The mitral valve was affected in 53 patients, most commonly in prostheses (28 bioprostheses and 2 mechanical). Aortic and mitral valves were together affected in 28 cases. The other patients had congenital defects or definitive pacemaker. Surgical treatment was indicated in cases of heart failure, refractory to medical treatment, valvar or prosthesis dysfunction secondary to infection, leak or arrhythmia. RESULTS: Cultures revealed that Streptococcus viridans and Staphilococcus aureus were the most prevalent microorganisms. Valve repair was possible in 3 patients of mitral group and one of aortic group. For the others, prostheses were used (mechanical for aortic valve and bioprostetic for mitral valve in the majority of the cases). Reoperation was frequent. Ventricular septal defect was the most common congenital pathology (3 cases) and 4 patients presented infective endocarditis in pacemaker wire. The global mortality was 16.3%. Abscess as a complication was presented in 18.2% of the patients. We used bovine pericardium for reconstruction with a surgical mortality of 17.2%. CONCLUSION: We concluded that the treatment for infective endocarditis represents a surgical challenge, in spite of the progress added to the diagnostic and therapeutic armamentarium of this pathology. Keywords: Heart valve diseases, surgery; Heart valve prosthesis implantation, mortality; Heart valve prosthesis implantation, treatment outcome; Heart valve prosthesis implantation, survival analysis; Endocarditis, surgery; Endocarditis, treatment outcome

OBJECTIVE: To assess the suitability of Partial Left Ventriculectomy (PLV) as a bridge to transplantation. BACKGROUND: Cohort study, prospective. MATERIAL AND METHODS: Fifty-three patients were submitted to PLV in a time frame of 5 years. Seven out of 53 patients, ages ranging from 37 to 64 years old, 5 males and 2 females, all with idiopathic dilated cardiomyopathy, were transplanted afterwards. Ejection fraction, NYHA functional classes, maximum oxygen consumption, left ventricular end-diastolic diameter and Quality of Life Scores were analysed preoperatively and then at three and six months and immediately before transplantation. RESULTS: The numerical values mentioned below are referred to the data obtained pre-ventriculectomy, at 3 and 6 postoperative months and immediately before transplantation. NYHA functional classes: 3.71 ± 0.49, 2.57 ± 1.13 (p=0.011), 3.0 ± 1.29 and 3.86 ± 0.38. Ejection fraction: 25.17 ± 6.15, 35.5 ± 8.41 (p=0.013), 32.33 ± 7.12 and 26.17 ± 3.76. Left ventricular end-diastolic diameter: 79.16 ± 10.85, 67.66 ± 9.2, 65.83 ± 9.57 e 64.25±8.99. Maximum VO2 was 8.12 ± 3.47 pre-VPE and increased to 13.2 ± 7.75 at six months (p=0.068). Quality of life scores: 4.29 ± 1.25, 3.0 ± 1.41 (p=0.050), 3.29 ± 1.8 e 4.57 ± 1.13. 7/53 patients (13.20%) were subsequently transplanted. Survival time, from PLV up to TX ranged from 7 to 33 months (18.71±11.78). Follow-up was 100%. CONCLUSION: Improvement in quality of life, NYHA functional classes and maximum VO2 consumption, as well as increase in ejection fraction and sustained decrease in left ventricular end-diastolic diameter, in short-term, can benefit patients previously excluded from TX and bring them back to the awaiting list. However, high immediate mortality rates in overall casuistry can limit its routine indication as a biological bridge to transplantation. Keywords: Heart ventricle, surgery; Heart transplantation; Heart ventricle, surgery, methods

OBJECTIVE: A device for pulmonary trunk (PT) banding with percutaneous adjustment was developed with the aim of inducing rapid hypertrophy of the subpulmonary ventricle. MATERIAL AND METHODS: It consists of a silicon cuff occluder which holds the pulmonary trunk; an extension tube that connects the cuff to an auto-sealing silicon button, in which water is injected percutaneously to inflate the cuff and adjust the systolic load to the subpulmonary ventricle. The hearts of seven young goats (average wt.: 8.7 kg) were submitted to systolic overload imposed by the device and assessed under hemodynamic, echocardiographic and morphologic aspects. Baseline myocardial samples of the right ventricular outflow tract were harvested for microscopic analysis (perimeter and area of the myocyte). The device was then placed on the PT. The pressures in the right ventricle (RV), PT and aorta were monitored. After convalescence, the protocol of insufflation of the banding device was initiated in order to achieve a RV systolic pressure 70% of the left ventricle systolic pressure. The hemodynamic and echocardiographic evaluations were performed every 24 hours. The RV systolic overload was maintained through a 96 hours period, with gradual insufflations of the cuff every 24 hours, according to the tolerance of the animal to the pressure load. After this period, the animals were killed for morphologic evaluation of the heart. Another nine goats (average wt.: 7.7 kg) were used as control group to compare the ventricle muscle weight. RESULTS: After 96 hours of RV systolic overload, it was observed an increase in systolic gradient RV/PT, from 10.1±4.3 mmHg to 60,0±11,0 mmHg and in the RV systolic pressure, from 22.4±4.1 mmHg to 71.0±10.0 mmHg (p<0.0001). Serial echocardiography showed an increase of the RV thickness, from 4.4±0.5 mm to 7.3±1.7 mm (p=0.001). Regarding RV weight, there was a 74% increase in the RV submitted to the systolic overload, when compared to the control group (p<0.0001). Under optic microscopy, a 27% increase in perimeter and 69% increase in area of the myocytes were observed (p=0.0001). CONCLUSIONS: The device considered in this work is effective and easily adjustable percutaneously, suggesting that the prepare of the subpulmonary ventricle could probably be accomplished in a 96 hour period of systolic overload. Improvements in the adjustment of the PT banding may allow better results of the two-stage Jatene operation in patients with transposition of the great arteries. Keywords: Heart ventricle, surgery; Heart ventricle, surgery, methods; Cardiac surgical procedures, methods; Transposition of great arteries; Pulmonary trunk banding device; Pulmonary artery, surgery

BACKGROUND: There are numerous advantages in closing the pericardial cavity after heart surgery and intrapericardial pneumonectomies. OBJECTIVE: To study the behavior of a natural latex membrane as a partial pericardium substitute. MATERIAL AND METHODS: Sixteen dogs divided into 3 groups were submitted to resection of an elliptical flap of the left anterolateral portion of the pericardium (7 x 5 cm): Group A (n=4) - the removed flap was immediately reimplanted; Group B (n=8) - the flap was replaced with a 0.3 mm thick natural latex membrane of equivalent area; Group C (n=4) - the latex flap was 0.7 mm thick. In all animals the flap was fixed with continuous 5-0 or 6-0 polypropylene sutures. In group C, 4 additional U-shaped stitches anchored with dacron pledgets were applied. All animals were submitted to ECG and to white cell counts during the preoperative period as well as to macro- and microscopic post mortem study. RESULTS: Group A - the self-graft was macro and microscopically intact, strongly adhering to the lung and loosely adhering to the epicardium; Group B - total suture dehiscence occurred in 1 animal and partial dehiscence in 2. The latex membrane did not adhere to the lung or to the epicardium. In 3 animals (37.5%) there was full regeneration of the pericardium underlying the natural latex, microscopically identical to the native pericardium. Group C - the sutures were intact and total pericardium regeneration was observed in 3 animals (75%). In the remaining animals of Groups B and C, the epicardium underlying the latex was slightly thickened, permitting easy visualization of the coronary vessels. Some areas with dense lymphocytes and plasma cells infiltrates, fibroblast and vascular proliferation were microscopically identified in its thickness; in some other areas the fibroblasts surrounded slits with mesothelial lining indicating irregular pericardium regeneration. No local infection or changes in white cell counts were observed and the ECG only showed T wave inversion in all groups. CONCLUSION: The natural latex membrane proved to be adequate for partial pericardium replacement in dogs kept under observation for up to 345 days, favoring regeneration of the native pericardium. Keywords: Pericardial substitutes; Prostheses and implants; Pericardium; Surgical, flaps; Cardiac surgical procedures, methods; Cardiac surgical procedures, adverse effects

A clinical case of a 38 year old male, with heart failure grade IV (NYHA) and angina at rest related to severe aortic regurgitation, right coronary ostial occlusion, and a sub-total occlusion of the left coronary ostium owing to syphilitic infection in the past is reported and discussed. Treatment was established implanting a mechanical aortic prosthesis and a direct left main angioplasty suturing a patch made of safenous vein. Follow up has been excellent and the patient is today having a normal life, free of symptoms. Keywords: Coronary arteries, surgery; Aorta, insufficiency, Myocardial revascularization, surgery; Aortic valve prosthesis; Aortic valve, surgery; Heart valve prosthesis, implantation; Aortic valve stenosis, surgery

The right pulmonary artery and left atrium direct communication is a rare anomaly. There are no more than 40 cases reported worldwide. Clinical presentation is variable, and patients can exhibit cyanosis, respiratory distress or heart failure. However, diagnosis can be easily made by image tests. Surgical treatment offers total healing with a few complications and mortality. Clinical follow-up without surgery can lead to remarkable complications such as brain abscess. Two cases on direct communication between right pulmonary artery and left atrium are reported. The embryogenic theories and anatomic varieties of this congenital abnormality will be discussed. Keywords: Cardiac surgical procedures, methods; Heart atrium, surgery; Pulmonary artery, surgery