An intraluminal shunt for off-pump coronary artery bypass grafting. Report of 501 consecutive cases and review of the technique.

BACKGROUND: Clinical or subclinical manifestations of coronary ischemia may occur when the target vessel is temporarily occluded during revascularization of the beating unsupported heart. Laboratory evidence has shown that even when the surface electrocardiogram is normal, action potential duration, conduction velocity, and regional electrocardiogram patterns change during clamping of the target coronary artery. In addition, local trauma to the endothelium and/or adjacent atherosclerotic plaque by encircling snares or mechanical clamps can lead to plaque disruption and late stenosis in the native vessel. METHODS: The authors report their experience with a continuous series of patients undergoing coronary grafting on the beating heart using an intraluminal shunt. This simple device maintains distal perfusion and prevents ischemia while at the same time protects the anastomosis from potential suturing errors. The shunt also keeps blood from obscuring the operators vision and thus makes snares and clamps unneccesary. Smooth unhindered removal of the shunt immediately confirms patency of the finished anastomosis. RESULTS: Off-pump coronary grafting was performed in 501 consecutive patients utilizing an intraluminal shunt. Three hundred and seventy three men (74.5%) and 128 women ranging from 34 to 92 years old (mean 60.4 years) underwent a total of 196 internal mammary artery and 596 saphenous vein grafts (1.58 grafts per patient) from November 1983 to December 1996 at the Santa Casa de São Paulo Hospital and Hospital Samaritano. Mean shunting time was 14 minutes per anastomosis. Thirty day hospital mortality was 1.39% (7 patients) and all deaths were from non-cardiac causes. Perioperative myocardial infarction occurred in 7 other patients (1.39%) all of whom survived. CONCLUSIONS: In selected cases coronary grafts can be safely constructed on the beating heart without ischemia using a simple and inexpensive intraluminal shunt. The device is easily inserted and removed without damage to the native coronary. In a large series of patients, operative mortality and morbidity were lower than with conventional heart-lung support and cardioplegic arrest.

Initial experience using an intraluminal shunt during revascularization of the beating heart.

BACKGROUND: For decades, surgeons have relied on extracorporeal circulation and induced cardiac asystole to provide a bloodless, motionless field in which to construct coronary bypass grafts. However, the technique of coronary grafting without heart-lung support is now being revitalized. The current resurgence of off-pump coronary artery bypass grafting and the advent of less invasive incisions make it imperative that technical advances be applied to maximize the safety of these procedures. METHODS: This report describes an inexpensive intraluminal shunt that maintains coronary perfusion, prevents ischemia, reduces backbleeding, and molds the suture line to prevent accidental missuturing of the posterior coronary wall. RESULTS: In 63 patients, saphenous grafts were placed to the left anterior descending (49), diagonal (9), and right coronary artery (27) without extracorporeal circulation using an intraluminal shunt. There were no deaths (0% mortality) and one perioperative infarction (1.5%). Complication and graft patency rates were comparable with those obtained by conventional techniques. CONCLUSIONS: Temporary intraluminal shunting greatly facilitates the surgeons' operative environment by permitting safe and precise construction of coronary artery grafts on the beating heart in a bloodless field. Intraluminal shunting may have future implications on the ability to perform safe and reproducible grafting on the beating heart through minimally invasive or endoscopic approaches.

[The Q wave in the electrocardiogram: necrosis or an electrically inactive area? Myocardial pseudoinfarct]. / Onda Q do eletrocardiograma: necrose ou zona eletricamente inativa? O pseudo-infarto do miocárdio.

Six patients with Q-wave myocardial infarction in the ECG, two with coronary disease, two with metabolic alterations, one with acute myocarditis and another with ischemic stroke had an improvement of ECG tracings with disappearance of the Q wave. All had normal plasmatic levels of CPK and CKMB. It is believed that metabolic transitory disturbance of the myocardium increases the rest transmembrane potential turning the cell nonresponsive to electrical stimulus and without mechanical activity (inactive electrical zone, not a necrosis zone, which is an anatomo-pathological diagnosis).

[Mitral valve replacement with porcine bioprosthesis in children. Evaluation of 29 patients during 12 years]. / Substituição valvar mitral por bioprótese porcina em crianças. Avaliação de 29 pacientes durante 12 anos.

PURPOSE: To analyze the clinical result of the mitral valve substitution for the porcine bioprostheses, the incidence of dysfunction caused by calcification and its importance related to the durability of bioprostheses and also the patients' survival. METHODS: Twenty-nine children of about seven to sixteen years old were operated on from November 1977 to August 1982 and all of them received porcine bioprostheses of low profile. RESULTS: There were three (10.34%) hospital deaths and nine other late mortalities. The follow-up period varied from 4 to 128 months with average of 58.17 months and with the loss of nine patients. An actuarial survival rate of 46.08% has been observed at 11 years after surgery. Calcification of 21 bioprostheses occurred in 14 out of 17 follow-up patients; 47.6% of them happened until the third year of pos-operative and 85.7% until the fifth year. Eleven patients were reoperated on with 9.09% of hospital mortality. There were no cases of thromboembolism. CONCLUSION: Porcine bioprostheses works well with an evident clinical improvement of patients, with no thromboembolic accidents. However, its durability has been affected by the high incidence of calcification, which is responsible for an increase in late morbidity and mortality. Mitral valve disease treatment in children must be conservative, in an attempt to solve the problem with the different available plastic technics and leave the valve substitution to be a last option. In that case, the preference is given to the homologous bioprostheses.

[Analysis of fever in 58 cases of infective endocarditis]. / Análise da febre em 58 casos de endocardite infecciosa.

PURPOSE: To evaluate if fever is an objective criterion in the assessment of response to antibiotic therapy and in the prognosis of patients undergoing treatment for infective endocarditis (IE). METHODS: Fifty-eight cases of IE, occurring from January 1980 to December 1989 have been analysed retrospectively in this study. Emphasis was given to the clinical history and body temperature changes during the first five weeks of treatment. Patients were divided in three groups according to the number of febrile peaks per week. Temperature was assessed weekly from each patient's highest peak weighed average. RESULTS: At the first exam, 52 patients (86.2%) presented fever. All patients had at least one episode of fever during their hospitalization. There seemed to be a relation between the number of febrile peaks during a one week period and the mean body temperature, so that these patients who presented four or more peaks in a week had a higher mean body temperature than those with two or less febrile peaks during the week. After the second week of treatment, patients with two or less febrile peaks had a 93.1% survival and average of 35.5 days of hospitalization, whereas those with three or more febrile peaks had 63.6% survival and an average of 47.5 days of hospitalization. CONCLUSION: The results of this study show that the intensity of fever is linked to the number of febrile peaks per week, regardless to treatment duration. Should there be three or more febrile peaks weekly after the second week of treatment, therapeutic strategy should be reviewed, considering even surgical treatment. In many cases, the persistence of fever represented the clinical expression of complications which determined a higher mortality rate and a longer hospitalization.

[Infective endocarditis. Study of 83 cases at the Hospital da Santa Casa de São Paulo]. / Endocardite infecciosa. Estudo de 83 casos no Hospital da Santa Casa de São Paulo.

PURPOSE: To analyse clinical aspects, diagnosis and treatment of infective endocarditis (IE), in order to guide medical procedures and indicate the surgical treatment. PATIENTS AND METHODS: 83 patients were submitted to clinical treatment of IE between January 1980 and December 1987; clinical aspects, laboratory and pathologic-anatomy findings, the site of infection and the entrance of micro-organism were studied. RESULTS: 37 (44.6%) patients were males. Fever was present in 75 (90.4%) cases, cardiac murmur in 76 (91.5%), splenomegaly in 28 (33.7%) and heart failure (III and IV) in 32 (39.8%) patients. Blood culture was positive in 55.5%; staphylococcus 50% of blood cultures; anemia was present in 66 cases (79.5%) and high serum mucoprotein in 58 (92%); echocardiography was 85.7% positive. The mortality was 39.76%; congestive heart failure was the main cause of death; 78.1% of these ones occurred in the first 15 days of antibiotic-therapy. The mitral valve was the one most impaired and the most frequent entrance of micro-organisms in oropharynx. CONCLUSION: Congestive heart failure, sepsis and systemic embolisms were the main complications that led the patient to death in course of IE, usually before 15 days of antibiotic-therapy. In these cases, we may hypothesize that prompt surgical treatment could have diminished the mortality of IE.

Nossa experiência com a utilização da bioprótese "Lifemed" de baixo perfil / Our experience with the use of the low-profile "Lifemed" bioprosthesis

E apresentada a experiencia com a utilizacao da bioprotese de valva aortica heterologa de baixo perfil modelo Lifemed em 390 pacientes. A valva mitral foi substituida em 228 pacientes, a aortica em 113 e mais de uma valva foi substituida em 49 pacientes. A mortalidade imediata foi 11,7%,4,4% e 18,3% respectivamente para as substituicoes mitral, aortica e dupla. Desses pacientes, 172 foram seguidos por maior tempo e constituem o objetivo do estudo, sendo 66 com substituicao mitral, 83 aortica e 23 com dupla substituicao da area cardiaca, nao houve caso de tromboembolismo e apenas um paciente foi reoperado por calcificacao da bioprotese. Conclue-se que no tempo de seguimento estudado a bioprotese Lifemed apresentou excelentes resultados