Volume 13 - Número 2

Partial left ventriculectomy has been performed as an alternative to heart transplantation in the treatment of severe cardiomyopathies. This study reports the clinical and left ventricular function results of this procedure in 37 patients with dilated cardiomyopathy. Methods: All patients were in class III (16) or IV (21) NYHA. Partial ventriculectomy was associated with mitral annuloplasty in 27 patients and with mitral replacement in two. Results: There were seven operative deaths (18.9%) and the surviving patients were followed from 2 to 36 (mean, 16.2) months. Another nine patients died during the first 6 months of follow-up due to progression of heart failure (5) related to arrhythmia (4). Actuarial survival was 56.7 ± 8.1% from 6 to 24 months. Unifactorial and logistic regression analysis of factors influencing outcome showed that mid-term survival was significantly affected by myocardial cell hypertrophy. A survival of 73.6 ± 10.1% at 2 years was observed for patients operated with mean myocardial cell diameter of less than 22 microns. Otherwise, functional class improved from 3.5 ± 0.5 to 1.7 ± 0.9 in the survivors (p < 0.001). Furthermore, left ventricular diastolic volume decreased from 523 ± 207 to 380 ± 148 ml (p < 0.001) and left ventricular ejection fraction increased from 17.1 ± 4.6 to 23 ± 8% (p < 0.001), whereas significant changes in cardiac index, stroke index and pulmonary pressures were found at 1 month follow-up. Although left ventricular diastolic volume tended to increase in the late postoperative period, left ventricular ejection fraction and hemodynamic variables did not change significantly. Conclusions: Partial ventriculectomy improves left ventricular function and congestive heart failure in patients with dilated cardiomyopathy for up to 24 months of follow-up. Nevertheless, this procedure's clinical application is limited by the high mortality observed in the first postoperative months. But it has opened new perspectives for its use through the identification that intrinsic changes of the myocardial fibers are affected by the p.o. prognosis of partial ventriculotomy. Keywords: Cardiomyopathy, congestive, surgery; Cardiac surgical procedures, methods; Heart ventricle, surgery

Eighty-three patients with endomyocardial fibrosis (EMF) underwent endocardial decortication and atrioventricular valve replacement or repair between December, 1977, and December, 1997. There were 66 (79.6%) female and 17 (20.4%) male patients, ranging in age from 4 to 59 years (mean, 31). Thirty-seven (44.5%) had biventricular disease 134 (41.0%) had disease of the right ventricle alone and 12 (14.5%) had EMF confined to the left ventricle. All were in functional class III or IV (New York Heart Association classification). Sixty-eight (81.9%) patients survived the operation and were followed-up for periods of time ranging from 1 month to 17 years. The total follow-up time was 6,290 patient/months (mean, 92 months). There were 15 late deaths but in 6 the cause was not related to the underlying disease. Four (5.8%) patients presented recurrence of the fibrosis and were reoperated and in 6 (8.8%) EMF appeared in the other ventricle. Five (7.3%) patients were reoperated to replace either a valve prosthesis or a native valve which had been preserved during the first procedure. Only 24 (45%) of the 53 living patients are in functional class I or II. The actuarial probability of survival at 17 years, including operative mortality, was 55%. In conclusion, surgical treatment of EMF should be considered a palliative procedure because surgery does not stop the progressive nature of the disease. However, surgical therapy is recommended for patients with EMF and heart failure as it is the only hope for them. Keywords: Endomyocardial fibrosis, surgery; Endomyocardial fibrosis, treatment outcome

The aim of this study is to evaluate the influence of the Maze Procedure in the treatment of rheumatic atrial fibrillation (AF) in patients with mitral valve disease (MVD). Between July 91 and June 94, 55 patients with rheumatic MVD (35 double dysfunction and 19 stenosis) and associated AF were operated on. The mean age was 51 yrs and 47 were female. All pts were in FC (NYHA) III or IV pre operatively. The patients were divided in 2 groups, according to the type of operation: GI - 20 patients submitted to MVD treatment and Maze Procedure and GII - 35 patients submitted only to MVD treatment. Pre-operative Echo showed left atrial diameter in G I and GII of 5,35 mm and 5.57 mm (p = 0.779). Mitral valve was replaced by biological prosthesis in 24 patients and conserved in 31 patients. Three hospital deaths were observed, with one in GI. After CPB, 37.1% of patients in GII remained in AF, and all patients in GI recovered regular rhythm (p < 0.0001). In the ICU, AF was detected in 82.4% in GII and maintained in 76.4% in a mean follow-up time of 38.5 months. In GI, AF was observed in 21.1% of pts in ICU and maintained in 5.2% in 41 months of follow-up (p = 0.0001). None of the pts in GI and 20.6% of pts in GII presented thromboembolic episode, 1 to 63 months after operation (p = 0.041). Four late deaths were observed (2 in each group), being 2 due to progression of valvular disease, 1 after a pulmonary infection episode and 1 with no cardiac cause. Maze Procedure was effective in treating AF in rheumatic MVD, maintaining the results in a late follow-up, preventing postoperative thromboembolic episodes and with acceptable morbidity and mortality. Keywords: Atrial fibrillation, surgery; Cardiac surgical procedures, methods; Heart valve diseases, surgery; Rheumatic heart diseases, surgery; Mitral valve, surgery; Atrial fibrillation, etiology; Heart valve diseases, complications

Five patients with anomalous connection of the left coronary artery to the pulmonary artery by an intramural route, whose ages ranged from 3 months to 11 months, were operated from 1987 to 1997. The diagnosis of the intramural aortic route was only made during the operation. In 4 patients a new technique was used. After establishment of the intramural aortic route, the pulmonary trunk was opened and the left coronary artery explored with a probe in order to identify its traject. Then, the aortic wall was opened and the intramural portion of the left coronary artery was opened longitudinally. The intima of the coronary artery was sutured to the intima and media layer of the aortic wall, creating an aortocoronary window. Finally, the origin of the left coronary was ligated. These 4 patients were followed-up from a period of 7 months to 10 years. They present clinical and echocardiographic improvement. All are in functional class I (NYHA), without medication. The only death occured 6 months after the operation. In this patient the intramural portion of the left coronary artery was divided from the aortic wall and the coronary artery reimplanted. There was several postoperative complications and the patient died suddenly 6 months after the operation. In this anomaly, the attempt to separate the left coronary artery from the aortic wall must be avoided. The described technique permits a safe and simple surgical correction of this rare anomaly, with good long-term results. Keywords: Pulmonary artery, abnormalities; Pulmonary artery, surgery; Coronary vessel anomalies, surgery; Cardiac surgical procedures, methods; Cardiovascular surgical procedures, methods; Aorta, surgery

The authors report their experience with the treatment of descending aorta aneurysms and dissection with or without arch involvement using an intraluminal auto-expandible prosthesis surgically inserted through the aortic arch. Eleven patients were operated on, nine were male and age varied from 49 to 78. The diagnosis was aneurysm in six (ruptured in two) and dissection in five (acute in two, ruptured in one). Four patients had associated surgical lesions: coronary artery disease (one), ascending aorta aneurysm (one), arch aneurysm (one) and aortic valve incompetence (one). All patients were operated under deep hypothermia and circulatory arrest and the prosthesis was introduced through longitudinal aortotomy in the arch. In four patients associated procedures were performed: aortic valve replacement (one), ascending aorta replacement (two), arch replacement (one) and coronary artery bypass (one). There was an intraoperative death due to intraoperative ascending aorta dissection and two hospital deaths due to multiple complications. Eight patients were discharged, one of them died three months after the operation. All the survivors were well and underwent image studies through image means that showed adequate correction of the aortic disease. The authors conclude that the use of endoluminal expansible prosthesis technique simplifies the operation and corrects the aortic disease. The morbidity and mortality observed is due to other factor independent of the technique. Keywords: Blood vessel prosthesis implantation, methods; Aortic aneurysms, thoracic, surgery; Aorta, thoracic, surgery

From October 1989 to May 1997, 40 patients with aortic dissection, aortic aneurysm, aortic coarctation or aorto-iliac occlusive disease, underwent reconstruction of their aorta using crimped bovine pericardial conduits processed in glutaraldehyde. Total reconstruction of ascending thoracic aorta and aortic valve with reimplantation of coronary arteries was performed in 9 patients, single ascending thoracic aorta in 6, descending thoracic aorta in 2, aortic arch in 1, thoracoabdominal aorta in 1 and the abdominal aorta was reconstructed in 21, also including patients undergoing aortoiliac or aortofemoral bypass. Hospital mortality was 20% (8 patients) and causes of death were low cardiac output, recurrence of aortic dissection, multiple organ failure and bleeding. Total follow-up was 128.4 patient-years with a mean follow-up of 4 years per patient. Late complications related to the conduit were observed in 4 patients, including a limb obstruction in 1 patient subjected to aorto-femoral bypass and infection in 3, resulting in pseudoaneurysm. All of them underwent reoperations, corresponding to an incidence of 3.1% ± 1.6% per patient-year. There were 5 late deaths and the causes were sudden death, coronary artery disease, pneumonia, septicemia, and metabolic complications of diabetes and renal failure, corresponding to an incidence of 3.9% ± 1.7% per patient-year. The 9-year actuarial survival was 61.5% ± 9.2%, including the surgical mortality, and the 9-year actuarial freedom from conduit failure due to primary tissue structural degeneration was 100%. The crimping design, similar to that used for synthetic vascular prosthesis, provides a circular tube which makes the construction of the anastomosis easier, retains its shape with bending and avoids kinking. The pericardium is very soft, easy to handle and suture, coapts nicely to suture lines resulting in a hemostatic anastomosis. The 9-year follow-up demonstrated a satisfactory performance, without any evidence of fibrosis, calcification or aneurysmal dilatation. Keywords: Heart valve prosthesis; Bioprosthesis; Blood vessel prosthesis; Aortic aneurysm, surgery; Aneurysm, dissecting, surgery

It is well known that aortic dissection may involve coronary arteries. However, only a few reports deal with surgical management of this problem. We present the report of the follow-up of 11 patients who suffered from ascending aortic dissection involving the right coronary artery and underwent surgical treatment at our Institution - InCor, Hospital das Clínicas, University of São Paulo Medical Center. The left coronary ostia was also affected in two patients. In seven patients the dissection was acute and at four, chronic. The ascending aorta was substituted by a Dacron tubular graft in all patients. Right coronary artery saphenous vein bypass or gore-tex graft to the coronary ostia or right coronary artery was performed in nine patients and reimplantation of both dissected coronaries in two. There were three early postoperative deaths (27.3%) due to low-output syndrome and myocardial infarction. One patient suffering from Marfan's Syndrome died during the fourteenth postoperative month due to hepathyc disease. Another Marfan's patient died from descending aorta rupture during the thirty-nineth month. The six surviving patients were followed from 78 to 96 months (mean 83 months). This experience suggests that although carrying high risk, involvement of the right coronary ostia in aortic dissection is an onset that can be successfully managed by some surgical procedures if done before irreversible complications arise. Keywords: Blood vessel prosthesis; Aneurysm, dissecting, surgery; Aortic aneurysm, surgery; Aorta, surgery

Early preconditioning of the spinal cord was investigated in rabbits, as an eventual protection mechanism, immediately before a 30 min ischemic period. Eight-seven New Zealand rabbits divided into 6 groups were assigned to the study. Ischemia of the spinal cord was induced by crossclamping (C) the abdominal aorta distal to the emergence of the left renal artery. Preconditioning was stimulated by short and sometimes repetitive ischemic periods, underlined in the text, and followed by different periods of reperfusion. Group I - Control: In 20 animals the aorta was crossclamped for 30 min. In two of them (10%) motricity and sensitivity of the hind-legs and tail were entirely restored; the other 18(90%) became paraplegic. Group II - Sham operation: 10 animals were operated as the ones in the previous group except for the fact that the aorta was not clamped. All of them (100%) had their sensitive and motor functions entirely restored. Group III - Preconditioning: 10 animals - (C) 1 min ® 15 min® (C) 30 min ® final reperfusion. All animals became paraplegic. Group IV - Preconditioning: 6 animals - (C) 1 min ® 5 min® (C) 2 min ® 5 min ® (C) 2 min ® 5 min ® (C) 30 min final reperfusion. Five rabgbits (83,33%) became paraplegic and 1 (16,66%) became monoplegic. Group V - Chlorpromazine: 20 animals were given chlorpromazine, intravenously, 2 mg/kg, 10 min before aortic crossclamping. Eleven animals (55%) had their sensitive and motor functions reestablished and 9 (45%) became paraplegic. Group VI - Clorpromazine + preconditioning: 21 animals were given chlorpromazine as those of group V and were preconditioned as follows: (C) 1 min ® 5 min ® (C) 1 min ® 5 min ® (C) 30 min ® final reperfusion. Nine animals (32.8%) recovered the sensitive and motor functions and 2(9.52%) experienced partial recovery. The remaining ones (47.68%) became paraplegic. Statistical analysis of the results demonstrated that: 1) there was no significant difference between groups III and IV, and when both of them were compared to group I (p < 0.05); 2) there was no significant difference between groups V and VI, but the difference was significant when both of them were compared to group I (p<0.05). Hystologic study - Twelve animals were assigned exclusively to histologic study: 6 control animals and 6 that were preconditioned as follows: (C) 1 min ® 5 min ® (C) 1 min ® 5 min ® (C) 30 min ® 5 h reperfusion. The percentage of ischemic neuronal cells showed a great dispersion of values, with no significant difference between groups, considering the median of those values (p < 0.005). Keywords: Isquemic preconditioning; Spinal chord; Spinal chord protection, methods

Purpose: To analyse the technique and results for correction of functional tricuspid insufficiency with Gregori's ring in the inverted position. Material and Methods: Between July 1991 and November 1997, 11 patients were operated on and the mean age was 37 years. The assessment of the patients was made by clinical symptoms (NYHA-FC) classification and echocardiography study. The ring was implanted in tricuspid position and the retilineal part of the ring was sutured with interruped stitches in the annulus of the anterior leaflet. The reason behind this technique was to reduce the natural ring that is dilated in that region. Eight patients was in functional class (FC) III or IV (72.7%) in the pre-operative period and atrial fibrilation (AF) was presented in 6 patients (54.5%). The mean right ventricular diameter was 34 mm (normal value is up to 26mm). Results: There was no early or late mortality. The associated procedures were: mitral valve replacement in 5 patients; closure of ASD in 2; aortic valve replacement plus mitral valve repair in 1; isolated mitral valve repair in 1; ressection of bilateral endomyocardial fibrosis (EMF) in 1 and myocardial revascularization in 1. Follow-up was possible in 10 patients (91%). Nine patients (89%) were in FC I or II. The patient in FC III presented residual mitral valve insufficiency post-correction of EMF. Three patients were in AF and 7 in sinus rythm and none in total A-V block. None of the patients were reoperated. The mean right ventricular diameter was 24.6 mm (p < 0.001). Conclusions: 1) The technique is safe and reproducible; 2) clinical improvement was evident; 3) reduction of the right ventricular cavity was statistically significant; 4) considering the excellent results of this technique, it can be employed, routinely. Keywords: Tricuspid valve insufficiency, surgery; Cardiovascular surgical procedures, methods; Cardiac surgical procedures, methods

An improved technique of atrial, retrograde cardioplegy is presented where the pulmonary artery trunk and the ascending aorta were snared with a tape passing behind both vessels through the transverse sinus of the pericardium. The pulmonary artery occlusion was controlled by the tourniquet avoiding its surgical isolation from the ascending aorta. With both venae cavae snared, blood / potassium (25 mEq/l) continuous cardioplegy was delivered through a catheter inserted in the right atrium ; the coronary ostia were directly perfused at 20 / 30 min intervals. Five patients were submitted to surgical procedures in the aortic root (Bental - De Bonno surgery, 1 case; aortic valve replacement, 3 cases; aortic valve replacement associated with surgical correction of aneurysm in the right coronary artery and ascending aorta, 1 case. The aorta crossclamp time ranged from 80 - 180 min. (mean 107.8 min.). All patients weaned from by-pass with haemodynamic autonomy. Immediate and in hospital post-operative recovery was normal . All patients were discharged in good clinical conditions. Keywords: Heart arrest, induced, methods; Aorta, surgery

An experimental model for total inversion of left lung circulation was developed. Using this model we will demonstrate that it is possible to reverse all the pulmonary circulation and that the lung remains functionally as well as morphologically normal. Circulation of the left lung was reversed in eight dogs. The blood from the pulmonary trunk was diverted to the pulmonary veins, and the return from the pulmonary artery to the left atrium. The dogs were reoperated after 15 days for a new analysis. In order to monitor the flow through the reversed system we performed an echocardiogram with color Doppler on the 9th post operative day. We used blood gas analysis from the aorta and the pulmonary artery to study the function status of this lung in the first and the second operation. The morphologic pattern was studied by comparing two biopsies of the lung, one before and one after the reversed flow. The results of blood gas analysis showed no significant difference between the samples of the aorta and pulmonary artery. The echocardiogram with color Doppler was a reliable method to study the inverted circulation. The histological study was able to demonstrate no difference in the morphology of the lung after the reversed circulation. It was possible to reverse all the left lung circulation. Functionally and morphologically the lung continued with its normal state. Keywords: Pulmonary circulation, physiology; Lung citology; Lung, physiology

Purpose: A new method for endocardial lead extraction, based on radiofrequency assistance, is proposed. The results obtained in the four initial cases are presented. Methods: Four patients with infected pacing leads were submitted to radiofrequency assisted lead extraction. Tined passive fixation leads were implanted in the right ventricle 8.5 to 18.8 (M = 12.9 ± 5.6) years before. Exhaustive continuous traction had been performed previously in four patients and failed to remove the leads. A Radionics RFG-3D Radio Frequency generator was connected to an anode fixed to the back of the patient. The cathode was the lead tip to be extracted. Up to three radiofrequency applications were performed in each patient. The energy released in each applications was up to 50 W during up to 60 seconds. This amount of energy was decided empirically based on the previous experience of the authors with radiofrequency ablation. No locking stylet was used. Results: Two patients had complete removal of their leads during RF application. In one patient radiofrequency energy disconnected the wire from tip of the lead, that rested in the myocardium. In another patient this procedures was not successful. No deaths or complications related to the technique occurred. Conclusion: RF can be used as an alternative method for lead extraction when laser assistance or countertraction cannot be used. Keywords: Pacemaker, artificial, adverse effects; Electrodes, implanted, adverse effects; Prostheses-related infections, therapy; Radio waves, therapeutic use

Recurrence of cardiac myxoma after excision is uncommon. The complete excision of the base of the tumor from the heart wall prevents its recurrence. In cases without wide resections , the probability of tumor recurrence rises. The authors report the case of a 26 year old male patient with recurrent left atrium myxoma presenting on two occasions. The patient was admitted with a left atrium tumor. Echocardiogram disclosed a tumor in interatrial septum. The patient is a Jehova's witness and did not receive whole blood or any blood products during the hospital stay. At operation a gelatinous mass fixed on interatrial septum was found. A wide resection was done, including the septal insertion of the tumor. Pathological examination revealed it to be a cardiac myxoma. Keywords: Mixoma, surgery; Heart neoplasms, surgery; Neoplasm recurrence, local