Contribución del neuropéptido Y a la fisiología de la co-transmisión simpática humana: estudios en biopsias de vena safena / Neuropeptide Y contribution to the physiology of human sympathetic cotransmission: studies in saphenous vein biopsies

Background: It is known that the sympathetic varicosities co-store and co-release norepinephrine (NE) together with adenosine S-triphosphate (ATP) and neuropeptide Y (NPY). Aim: To describe the chemical characterisation of stored and released NPY from the varicosities of sympathetic nerve terminals surrounding segments of the human saphenous vein, and the vasomotor activity of rings electrically depolarized or contracted by the exogenous application of the co-transmitters. Material and methods: Saphenous vein tissues were obtained from patients undergoing elective cardiac revascularization surgery. Results: The chromatographic profile of NPY extracted from biopsies is identical to a chemical standard of human NPY. Upon electrical depolarisation of the perivascular sympathetic nerve terminals, we demonstrated the release of NPY to the superfusion media, which did not exceed a 1percent of its stored content. The release of the peptide is sensitive to guanethidine, and to extracellular calcium, suggesting that the mechanism of its release is exocytotic in nature. The electrically evoked release of NPY is dependent on the frequency and duration of the electrical pulses. Phenoxybenzamine reduces the electrically evoked release of NPY. Exogenous application of NE and ATP contract saphenous vein rings; the simultaneous application of NE plus ATP causes a synergic response, effect which is further potentiated by the joint co-application of 10 nM NPY. Conclusions: Present results highlight the role of NPY as a sympathetic co-transmitter in the regulation of human vascular tone

Aneurisma roto de aorta torácica descendente: tratamiento endovascular / Endovascular treatment of a ruptured thoracic aorta aneurysm

In 1991, a technique to exclude aortic aneurysms from circulation inserting an endoluminal graft through the femoral artery, was described. This procedure, usually used for elective abdominal aneurysms, can also be used in the thoracic aorta. We report a 41 years old male with a Marfan syndrome, presenting with a descending aorta aneurysm that ruptured to the mediastinum and pleural cavity. He was compensated hemodynamically and an endovascular stent-graft was deployed at the ruptured zone, through the femoral artery. The postoperative evolution of the patient was uneventful. This technique will allow a less invasive treatment of ruptured aortic aneurysms

Infección de prótesis de aorta ascendente: tratamiento con aseo quirúrgico, preservación de prótesis y transposición de colgajo muscular en dos casos / Infection of ascending aortic graft: treatment with surgical cleaning, graft preservation and transposition of muscle flaps, report of 2 cases

Mediastinitis with graft infection is a serious complication of ascending aorta replacement. We report two cases of graft infection, treated with surgical cleaning, graft preservation and transposition of muscle flaps. A 62 years old male was admitted 34 days after an ascending aortic grafting due to a sternal dehiscence and mediastinitis. Antimicrobial treatment was started and a surgical cleaning performed, leaving an open sternotomy. Three days later, the thoracic cavity was closed with a rectus abdominis muscle flap. After 23 months of follow up, the patient is well and without evidence of infection. A 74 years old male was subjected to an aortic valve and ascending aorta replacement and a myocardial revascularization. In the postoperative period, the patient developed septic signs, and a purulent drainage. A CAT scan showed a liquid collection surrounding the aortic graft. On tW Sixteenth postoperative day, a surgical cleaning was performed and the thorax was closed with the pectoralis major muscle. After 10 months of follow up, the patient is in Good condition and without evidence of infection

Reoperaciones coronarias: análisis retrospectivo de 16 años de experiencia / Coronary artery bypass grafting reoperation: a 16 years retrospective analysis

Background: Coronary artery bypass grafting (CABG) reoperation is being performed with increasing frequency. Aim: To assess the early and long term results of coronary reoperations in our institution and to identify prognostic factors. Patients and methods: 214 patients subjected to coronary reoperations between 1983 and 1999 were retrospectively studied. Results: Mean age was 64.2 years (range 42-79 years), 202 (94.4 per cent) were male and 12 (5.6 per cent) female. The mean interval between the operations was 125.7 months (range 6-252 months). 10 (4,6 per cent) were emergency surgeries. Overall operative mortality was 5.6 per cent (11 deaths) and in 5 patients (3.4 per cent) a perioperative myocardial infarction was noted. Univariate analysis identified moderate or severe left ventricular failure (p=0.048) as predictor of increased operative mortality, meanwhile age over 75 years (p=0.02) and moderate or severe left ventricular failure (p=0.01) were identified as predictors of increased in hospital mortality in the multivariate analysis. Follow up of in hospital survivors (mean interval 65 months, range 4 to 190 months) documented a 5 years survival rate of 82.9 per cent, a 10 years survival rate of 73.1 per cent and a 15 years survival rate of 53.4 per cent. Moderate or severe left ventricular failure (p <0.0001) and emergency surgeries (p=0.007) were identified as factors influencing the late survival in the stepwise logistical regression analysis. Multivariate analysis identified left ventricular failure (p=0.01) and peripheral vascular disease (p=0.01) as predictors of decreased late survival. Conclusions: Coronary reoperation has a low mortality in patients with a normal ventricular function and also has an excellent overall and disease free survival in the first 10 years of follow up. Left ventricular function is an independent risk factor increasing in hospital and late mortality

Cirugía de la insuficiencia mitral isquémica / Surgery for ischemic mitral regurgitation

Background. Ischemic mitral regurgitation (IMR) is a severe condition which may be best treated by surgery, nowithstanding a relatively high mortality rate. Objectives. To evaluate the results of mitral valve replacement or repair in patients with IMR. Patients and methods. Retrospective review of the clinical records in 29 patients with IMR who were surgically treated from 1990 to 1999. They represent 8 percent of surgical procedures on the mitral valve. Results. Mean age was 67 ñ 9 years. Surgery was performed urgently in 19 patients (66,5 percent). NYHA functional class was 3.4 ñ 0.8. The mechanism of IMR was annular dilatation and spreading of papillary muscles in 18 patients, papillary muscle rupture in 9 and fibrosis in 2. Mitral valve replacement was performed in 14 patients and mitral valve repair in 15. Twenty four patients (83 percent) had concomitant myocardial revascularization. Overall surgical mortality was 24 percent; 26 percent for mitral replacement and 13 percent for mitral valve repair (p=0.215). On follow up of 26ñ33 months, one year survival was 76ñ0.8 percent and 5 years survival was 59ñ12 percent. Excluding in hospital mortality, survival was 100 percent at one year and 78ñ14 percent at 5 years. Functional class improved in all survivors, to 1.4ñ0.5. Late echocardiographic evaluation of patients with mitral valve repair showed absence of mitral regurgitation in 58 percent, 1+ MR in 17 percent and 2+ MR in 25 percent. Conclusion. In spite of a high perioperative mortality, surgery for IMR is a valuable procedure for patients with an otherwise highly lethal disease

Operación de Fontan: resultados inmediatos y a mediano plazo con anastomosis cavopulmonar total / Fontan procedure: early and mid-term results wiht total cavopulmonary anastomosis

Background: During the last five years, 65 patients with univentricular heart have been treated surgically in our institution, according to a protocol of staged operations that have been previously reported. Aim: To evaluate the early and mid-term outcome of those patients that have completed their staging protocol by means of a Fontan procedure. Patients and Methods: Between April 1996 and June 2001, 23 patients (age 16 to 223 months) underwent a Fontan procedure, 15 with an intracardiac lateral tunnel technique and 8 with an extracardiac conduit. A retrospective review of their clinical, surgical, echocardiographic, angiographic and hemodynamic data was performed, trying to identify risk factors for both mortality and functional capacity (FC). Follow up was complete in all survivors. Results: Three patients died early after surgery (13.04 percent). Excessive pulmonary blood flow was a risk factor for early death (p= 0.03). One patient died at 14 months. Follow up was 29.9 months (1-63). For those who survived the operation, five years survival was 93.3 percent. The majority of patients are in FC I or II, with no related risk factors. Conclusions: Our current results are comparable with those of larger series. Patients reach good FC and mid-term survival, irrespective of type of single ventricle or the surgical strategy

Canulación de arteria axilar para circulación extracorpórea / Cannulation of axillary artery for extracorporeal circulation

Background: When the ascending aorta and the femoral artery cannot be used for extracorporeal circulation, an emerging alternative is the use of axillary artery. Aim: To report the experience using the axillary artery for extracorporeal circulation. Patients and methods: Between November 1998 and May 2002, 22 patients (14 male) were operated with extracorporeal circulation, cannulating the axillary artery. Briefly, an incision is made below the middle third of the clavicle and a cut is made on major pectoris muscle. Minor pectoris muscle is retracted and axillary artery is exposed. It is cannulated directly or with the aid of a prosthesis. Results: Right axillary artery was used in 21 patients and in 20 it was cannulated with the aid of a prosthesis. Mean flow was 4.5 + 0.6 l/min. The most common indications were aortic dissection or aneurysms. The most common procedures done, were ascending aorta replacement in 8 cases and replacement of ascending aorta and aortic arch in 5. Thirty five percent of operations were emergencies and 32 percent were reoperations. In 15 patients (68 percent), a circulatory arrest was done. Of these, retrograde brain perfusion was used in 9, antegrade brain perfusion through the same axillary artery was used in 2 and mixed perfusion was used in 2. One patient had a complication related to the axillary cannulation. None had cerebrovascular accidents or thromboembolic complications. Two patients died in the postoperative period. Patients were followed up to 42 months after the procedure and no secondary complications of the cannulation were detected. Conclusions: When the ascending aorta and the femoral artery cannot be used, axillary artery is a good alternative for extracorporeal circulation

Tratamiento de la insuficiencia cardíaca avanzada mediante trasplante de corazón / Heart transplantation as a treatment for advanced heart failure

Background: Heart transplantation currently provides the most effective treatment for advanced heart failure. However, medical therapy for this condition has also improved, heart donors are scarce and the cost of the procedure is high. Therefore the indications and management of these patients need reevaluation. Aim: To analyze the results of 24 patients submitted to heart transplantation for end-stage heart failure needing repeated hospitalizations and i.v. inotropes for compensation. Patients and methods: The group was comprised by 21 men and 3 women with a mean age of 36.8 years, mean left ventricular ejection fraction 19ñ4.5 percent, mean systolic pulmonary artery pressure 48ñ13 mmHg (24-70) and mean pulmonary vascular resistance 2.6 Wood Units (1-5). Fourteen patients (58 percent) had a previous median sternotomy. Immunosupression did not include induction therapy and steroids were discontinued early...

Experiencia de 36 años con marcapasos implantables: un análisis histórico / A 36 year experience with implantable pacemakers

Background: The implantation of pacemakers improves cardiac function and quality of life, in particular with dual chamber DDD and DDDR modes. Aim: To evaluate our clinical experience and results on pacemaker implantation, from 1963 to 1998. Material and methods: Computerized data collected from 2,445 consecutive paced patients was reviewed. A total of 3,554 operative procedures were performed, including 412 procedures for complications and 697 pacemaker replacement. Patient survival was determined from clinical records, inquiry to pacemaker manufacturers and death certificates from Servicio de Registro Civil e Identificaci-n de Chile (Chilean Civil and Identification Registry). Results: Use of dual chamber (DDD and DDDR) pacemakers increased progressively up to 74 percent from 1988 to 1998. Complication rate was 42 percent in the 1963-1976 study period, it decreased to 10.6 percent in the 1977-1987 study period, and to 5.6 percent by 1988-1998. Only two patients died during surgery in the study period (0.08 percent). In the 1977-1987 period, pacemakers lasted 10.6 years. Survival rates were 52 percent at ten years, 33 percent at 15 years, and 21 percent at 20 years, with a median survival of 11.7 years, and 7.24 years in patients over 80 years old. Conclusions: Transvenous permanent pacing can be accomplished today with a low complication rate, mainly due to better technology and surgical procedures

Aneurismas micóticos y embolías múltiples en una paciente con endocarditis infecciosa / Mycotic aneurysms and multiple emboli in a patient with infectious endocarditis

Sepsis from an infected cardiac value can lead to bacterial seeding and destruction of the arterial wall with formation of a mycotic aneurysm. The natural history of these lesions is the rupture. We report the case of a 20 year old female who was admitted to our institution with massive mitral regugirtation and emboli of the central nervous system and both lower extremities. She underwent emergency valve replacement and then, staged treatment of her ischmic legs and multiple asymptomatic mycotic aneurysms. Superior mesenteric, right common iliac and left superficial femoral arteries. A splenectomy was required to treat a splenic abscess. An aneurysm of a peripheral branch of the middle cerebral artery was medically treated, demonstrating reduction in size on subsequente angiogram.She recoverd uneventfully and remains asymptomatic after 20 months of follow up. The development of new diagnostic and therapeutic tools had led to a decrease ot these complications during infectious endocarditis. However, in the patient with late diagnosis and symptoms in different territories, the mycotic aneurysm must be kept in mind to provide the patient with appropriate treatment

Endartectomía carotídea simultánea con revascularización miocárdica: experiencia en 27 pacientes / Carotid endartectomy simultaneous with myocardial revascularization: experience in 27 patients

Atherosclerosis is a systemic disease that may involve more than one territory. Myocardial infarction can occur after carotid endartectomy and stroke is a well documented morbidity of coronary artery bypass grafting. To optimize results, we have performed concomitant carotid endartectomy and myocardial revascularization in selected cases, with severe disease in both territories. During a 13 year period, 27 patients were submitted for this procedure, 21 (77,8 percent) were male and the average age was 67.6 years (range 59-81). All patients had high grade internal carotid artery stenosis, 5 (18.5 percent) were symptomatic. Coronary artery disease symptoms were: unstable angina in 12 patients (44,4 percent) and effort angina in 15 (55.6 percent). Two patients (7.4 percent) required reintervention for postoperative bleedinng. Two patients (7.4 percent) had transient renal dysfunction. One patient, with multiple organ failure, died on the 16th postoperative day (3.7 percent). Follow up was obtained in 26 patients (96.3 percent). Survival at 5 years was 80.6 percent, 95.7 percent of those patients were free of any neurologic symptoms. Combined carotid and coronary surgery is a safe treatment option for atherosclerosis of multiple territories in selected patients, long term benefits are also obtained

Liberación de neuropéptido tirosina (NPY) de los terminales nerviosos en vasos mamarios / Liberation of tyrosine neuropeptide (NPY) from mammary vessels nerve endings

En este estudio caracterizamos la liberación de NPY de biopsias de la arteria y vena mamaria. Se induce la liberación de los neurotransmisores por medio de despolarización eléctrica de los nervios simpáticos perivasculares. Con estímulo de 70 V, 0,5 msec, 40 Hz por 5 min, segmentos de la arteria mamaria liberan 17,7 ñ 6,7 fmol (n=4) de NPY, la vena libera 4,3 ñ 1,5 fmol (n=4), valores que corresponden a un 1-2 por ciento del NPY en la biopsia. El NPY liberado por estímulo eléctrico no es metabolizado en la sinapsis neuroefectora. La liberación del NPY al medio de superfusión tiene un curso temporal lento, la máxima liberación ocurre a los 10 min del estímulo. La liberación del NPY es dependiente de la duración del estímulo (coeficiente de correlación = 0,647, p<0,01); y de la frecuencia de estimulación (coeficiente de correlación = 0,611, p<0,05), indicando que la liberación es un proceso controlado por la frecuencia de la descarga y por la intensidad del estímulo simpático vasomotor. El proceso de liberación es dependiente del calcio, ya que en ausencia de calcio extremo, la liberación de NPY se reduce en 78 por ciento. El NPY actúa sobre receptores postsinápticos, donde produce un efecto facilitador significativo de la acción vasomotora de NA y ATP. En conclusión, NPY se libera al espacio sináptico por exocitosis, donde participa junto a NA y ATP en la regulación del tono vasomotor simpático

Rotura de músculo papilar en el infarto miocárdico / Papillary muscle rupture in myocardial infarction

We report 9 patients with acute mitral regurgitation secondary to post-infarction papillary rupture operated between 1980 and 1992. Seven cases had posterior papillary muscle rupture. All patients were in critical conditions with pulmonary edema at the moment of surgery. In 8 cases, mitral valve replacement was performed (4 with mechanical prosthesis) and in 1, the value was repaired with papillary muscle reimplantation. Six cases were also subjected to myocardial revascularization with saphenous vein grafts. Two patients (22 percent) died during the postoperative period and 4 had postoperative complications. The seven survivors have been followed during 6 to 115 month. Of these, one died six months after surgery dur to congestive heart failure, 3 are in functional class I and the rest in functional class II. It is concluded that, although mitral valve replacement for papillary muscle rupture has a high operative mortality and morbidity, long term results are satisfactory

Cirugía de revascularización miocárdica en los primeros 15 días de evolución del infarto / Miocardial revascularization surgery in the first 15 days of infarction evolution

Revascularization significantly improves early and late prognosis in acute myocardial infarction and has prompted substantial changes in therapeutic strategies. We report 140 patients aged 60.3 years old (123 male) operated within 15 days of sustaining an acute myocardial infarction, between january 1984 and december 1989. Coronary angiogram showed single vessel disease single vessel disease in 8 (6 percent), double vessel disease in 32 (23 percent), triple vessel disease in 85 (61 percent) and left main vessel disease in 13 (9 percent). Indications for surgery were ponstinfarction angina in 92 patients (66 percent), multiple severe coronary stenosis in 18 (13 percent), infarction of less than six hours from onset in 16 (11 percent), acute angioplasty failure in 7 (5 percent) and cardiogenic shock in 7 (5 percent). Thirty one patients were operated during the initial 24 h of infarction (16 with less than 6 h) 14 between the second and third day and 95 between the fourth and fifteenth day. Overall mortality was 4.3 percent (6/140). Among patients with failed angioplasty and cardiogenic shock, mortality was 23 percent (7/140), among patients with postinfarction angina this figure was 2.1 percent (2/92). Five years actuarial survival was 95 percent and the actuarial probability of being free of acute myocardial infarction, angioplasty or reoperation at five years was 99 and 100 percent respectively. It is concluded that early surgical revascularization in acute myocardial infarction is safe and has excellent long term results

Tromboendarterectomía pulmonar: tratamiento quirúrgico del tromboembolismo pulmonar crónico bajo paro circulatorio con hipotermia profunda en un caso / Pulmonary thromboendarterectomy: surgical treatment of chronic pulmonary thromboembolism under circulatory arrest and with deep hypothermia in 1 case

Pulmonary thromboendarterectomy under circulatory arrest and deep hypothermia is presently a curative treatment for pulmonary hypertension secondary to chronic pulmonary artery thromboembolic occlusion, but is still not frequently performed around the world. We report here the first successful pulmonary thromboendarterectomy under circulatory arrest performed in Chile. The patient was a 37 years old white man, high school teacher, with a 5 months history of effort dyspnea and cough. Pulmonary hypertension secondary to chronic pulmonary thromboembolism was confirmed by angiography and echocardiography. The patient was operated on april 27, 1995. After the operation the patient had an enmediate and maintained normalization of his pulmonary hemodynamics. He presented periods of delirium that postponed mechanical ventilation disconnection until the 7th postoperative day, after which he had an uneventful neurological recovery. Before hospital discharge a control angiography showed complete patency of the pulmonary artery system with no evidence of residual thrombi. Presently he is enjoying a normal life and back to his teaching activities

Revascularización miocárdida con una y dos arterias mamarias: resultados clínicos y seguimiento alejado / Myocardialrevascularization with 1 or 2 mammary arteries: clinical results and long term follow up

Patients and methods: One hundred and eight randomly selected patients who received one mammary artery for myocardial revascularization and 108 patients, matched for prognostic factors, who received two mammary arteries were studied. These patients were followed for a mean of 4 years (range 1 to 12 years). Operative complications, hospital mortality and long term probability of being free of disease were compared in both groups. Results: Operative mortality was similar in both groups (0,9 percent). Patients that received two mammary arteries had a higher frequency of operative wound complications. Long term survival was 84 per cente in patients who received one and 83 per cente in patients who received two mammary arteries. The probabilities of being free of myocardial infarction (92 and 82 percent respectively) and angina (94 and 86 percent respectively) were lower in the later group. Conclusions: Patients who received two mammary arteries had a higher probability of a long term disease free survival than patients who received one mammary artery

Cirugía coronaria: veinte años de seguimiento / Results of coronary surgery: a 20 years experience

Background: Since the first surgical coronary revascularization done in Chile in 1971, 5000 such procedures bave been performed. Aim: To assess the long term results of coronary revascularization surgery in our institution and to identify prognostic factors. Patients and methods: Five groups of 100 patients each, composed by the first consecutive patients subjected exclusively to coronary bypass surgery in the years 1975, 1980, 1985, 1990 and 1995 were retrospectively studied. Results: Mean age of Patients increased from a median of 52 years old in 1975 to 62 yean old in 1995. No changes in the frequency of diabetes, hypertension, high serum cholesterol or prvious mycardial infarction were observed. There was an increase in the Proportion of patients with a recent (< 30 days) infarction that were operated along time. Seventy percent of patients had triple vessel disease or LMT and this proportion did not change. The number of grafts per patients increased form 1.9 to 3.4 and the use of arterial conduits from 0.18 to 0.81. Perioperative mortality remained constant and was 1.6 percent. Follow up information was obtained for 93 percent of 492 survivors. Actuarial survival at 5, 10, 15 and 20 years was 93ñ1, 82ñ2, 62ñ3 and 41ñ4 percent respectively. Ninety eight ñO.7, 89ñ2, 73ñ4 and 65ñ5 percent of patients remained free of a new myocardial infarction in the same lapses, respectively. Ninety seven ñl, 94ñ2, 76ñ4 and 47ñ7 percent of patients remained free of a new operation. Stepwise logistical regression analysis identified as bad Prognostic factors, in decreasing order: cardiac failure, diabetes, smoking, hypercholesterolemia and age at the moment of operation. Conclusions: Coronary artery bypass surgery provides good and long lasting clinical improvement. The prognosis of patients is influenced by the presence of cardiac failure, some well known coronary risk factors and age at the moment of operation

Cierre de comunicación interauricular a través de miniesternotomía / Minimally invasive sternotomy for closure of atrial septal defect

Objetivos: el uso de una miniesternotomía para la reparación de ciertas cardiopatías congénitas tendría beneficios cosméticos, menor dolor postoperatorio y una hospitalización más breve, sin sacrificar los resultados de la intervención. Nuestro objetivo es describir la técnica quirúrgica y presentar los resultados de una serie inicial de pacientes. Material y método: desde enero de 1998 adoptamos la técnica de miniesternotomía para el cierre de comunicación interauricular (CIA) en pacientes pediátricos. Desde entonces, hasta diciembre de 1998 se intervinieron 16 pacientes (mujeres: 8; hombres: 8), de entre 9 meses a 13 años de edad (x:3,5 años), con peso de entre 8 a 36 kg (x:15,4 kg). Trece pacientes presentaban una CIA tipo ostium secundum, 2 una CIA tipo ostium primum con cleft de la válvula mitral y 1 paciente una CIA tipo seno venoso-cava inferior. Se describe la técnica quirúrgica. Resultados: en 8 pacientes se realizó cierre directo del defecto y en 8 se empleó parche de pericardio; en 2 se cerró un cleft mitral. En ningún paciente fue necesario ampliar la estemotomía. El tiempo de circulación extracorpórea fluctuó entre 20 a 76 minutos (x:49,5) y el clampeo aórtico entre 7 a 53 minutos (x:20,5). El ecocardiograma pre-alta no demostró defectos residuales en ningún paciente. La estadía hospitalaria postoperatoria fue entre 3 y 4 días y el dolor fue subjetivamente menor. No hubo morbilidad ni mortalidad. Comentario: la miniesternotomía permite un adecuado y seguro acceso para la reparación de CIA en pacientes pediátricos, con buenos resultados cosméticos, corta estadía hospitalaria y aparentemente menos dolor. Esta técnica tendría ventajas sobre el uso de toracotomía anterior derecha y puede utilizarse para reparar otros defectos, como comunicación interventricular y canal auriculoventricular completo

Mini esternotomía en cirugía valvular / Minimally invasive sternotomy for valvular heart surgery

Antecedentes: desde mediados de la presente década se han propuesto distintos accesos mínimamente invasivos en cirugía cardiovascular, entre ellos la miniesternotomía. Objetivo: presentar nuestra experiencia inicial en cirugía valvular a través de miniesternotomía. Pacientes: entre octubre 1997 y diciembre 1998, se efectuó un reemplazo valvular aórtica y en otra un reemplazo valvular mitral, a través de una miniesternotomía media en "J". Nueve pacientes eran hombres. El promedio de edad fue de 53,6 años (29-73). Todos los pacientes fueron operados con monitorización ecocardiográfica transesofágica. Técnica quirúrgica. Se efectuó una esternotomía media en "J" en el 3º o 4º espacio intercostal derecho con una incisión cutánea menor a 10 cm en todos los casos. Para el retorno arterial se canuló la aorta ascendente y para el drenaje venoso, la orejuela derecha con una cánula única. La protección miocárdica se efectuó con cardioplegia cristaloide infundida en forma anterógrada y/o retrógrada a 4ºC. El drenaje de las cavidades izquierdas se efectuó con un catéter introducido a través de la vena pulmonar superior derecha. Los reemlazos valvulares aórticos se efectuaron a través de una aortotomía oblicua y el reemplazo valvular mitral a través de una auriculotomía izquierda superior...