Ligadura de la arteria coronaria descendente anterior izquierda en ratas: técnica quirúrgica / Ligation of left anterior descending coronary artery: surgical technique

Background: An experimental model for ligation of the left anterior descending coronary artery (ADA) in rats has been commonly used in research into ischemic cardiopathy. However, this procedure is very difficult, with a high mortality rate. There is little information in the literature regarding its technical aspects. Our objective was to describe a surgical technique for ADA ligation in rats. Material and Method: Fifty-one Sprague-Dawley male rats weighting 230 +/- 20 gr were anaesthetized and connected to mechanical ventilation. Through a left-side thoracothomy we ligated the ADA 2 mm below the junction of the pulmonary artery and the left atrial appendage. The next day we performed transthoracic echocardiography to confirm our results. Results: The mortality rate was 7.8 percent (4 out of 51). The main cause of death was hemorrhage during surgery. The average time for the procedure was 45 +/- 5 min. We confirmed hypokinesia of the anterior lateral wall in 100 percent of the surviving rats. Discussion: This procedure was reproducible and safe, with less than 10 percent mortality.

Introducción: El modelo experimental de ligadura de la arteria coronaria descendente anterior izquierda (ADA) en ratas, ha sido de gran ayuda para el estudio de la cardiopatía isquémica. Sin embargo, es un procedimiento difícil de realizar y con alta mortalidad operatoria. Existe poca información de sus aspectos técnicos. El objetivo de nuestro trabajo fue describir en detalle la técnica quirúrgica de la ligadura de la ADA en ratas. Material y Método: Se utilizaron 51 ratas machos Sprague-Dawley 230 +/- 20 gr de peso anestesiadas y conectadas a ventilación mecánica. A través de una toracotomía izquierda se ligó la ADA, 2 mm debajo de la intersección entre la arteria pulmonar y la orejuela izquierda. Al día siguiente se realizó una ecocardiografía transtorácica para confirmar la presencia de hipocinesia. Resultados: La mortalidad operatoria fue de 7,8 por ciento (4 de 51). La principal causa de muerte fue la hemorragia en el intraoperatorio durante la curva de aprendizaje. El tiempo operatorio promedio fue de 45 +/- 5 min. Se confirmó la presencia de una hipocinesia de la pared anterolateral en el 100 por ciento de las ratas supervivientes. Discusión. Esta técnica es un procedimiento reproducible y seguro, con una mortalidad menor al 10 por ciento.

Resultados alejados de la cirugía reparadora de la insuficiencia mitral isquémica / Long-term results of mitral valve repair for ischemic mitral insufficiency

Background: The preferred treatment for ischemic mitral insufficiency is mitral valve repair with a prosthetic ring, because it does not deteriorate left ventricular function, allowing better immediate and long-term results. Aim: To assess long-term results of mitral annuloplasty with a prosthetic ring for ischemic mitral insufficiency. Patients and Methods: One hundred patients (68 men), with a mean age of 65.7 ± 8.6 years were included. They underwent a mitral annuloplasty with a prosthetic ring to treat ischemic mitral insufficiency, between February 1992 and May 2009. Fortyfour had a history of prior myocardial infarction and 46 had an evolving acute coronary syndrome. The inferior left ventricular wall was involved, exclusively or associated with an adjacent wall, in 72 cases. Coronary artery bypass grafts were performed in 92 patients and 32 required intra-aortic balloon pumping at some time during the peri-operative period. Results: Operative mortality was 10% (10 patients). During follow-up 30 patients died, at an average of 39 months after surgery (range: 3-142 months). Actuarial long-term survival rates at 1, 3 and 5 years were 79%, 72% and 64.5%, respectively. Trans esophageal echocardiogram performed in the operating room showed none or minimal residual mitral insufficiency in 96% of the cases. Echocardiographic follow-up was completed in 80% of the survivors; 79% of them had no or minimal mitral insufficiency. Only one patient was re-operated on due to severe mitral insufficiency and 4 required a permanent pacemaker. Conclusions: Considering the critical illness of these patients, good long-term results were observed after treatment of ischemic mitral regurgitation performing a mitral annuloplasty with a prosthetic ring.

Reemplazo valvular aórtico con prótesis biológica en pacientes mayores de 70 años con estenosis aórtica / Aortic valve replacement with bioprosthesis in patients 70 years old or older with aortic stenosis

Background: Aortic valve stenosis is the most prevalent valvulopathy in the elderly, but it is frequently undertreated. Aim: To assess early and long term results of valve replacement with bioprostheses in patients 70 years old or older with aortic stenosis. Patients and Methods: A review of the database of the Cardiovascular Surgery Service of our hospital, for the period 1990-2007, identified 156 patients with aortic valve stenosis, aged 76.7 ± 4.5 years (67 percent males), that were subjected to an aortic valve replacement with bioprosthesis. Seventy eight (50 percent) were in functional class III-IV. Six patients had emergency surgery. In 67 patients (43 percent) coronary artery bypass graft were performed. Long term mortality was ascertained obtaining death records from Chilean death registry. Results: Operative mortality was 3.2 percent (5 patients). Four patients (2.6 percent) required a reoperation due to bleeding. The mean follow up was 66 ± 41 months. The survival rate at 1, 3 and 5years was 94 percent, 88 percent and 80 percent, respectively. Forty two patients (27 percent) were 80years old or older. In this sub-group, 1 patient (2.3 percent) died during the peri operative period and the estimated survival rate at 1, 3 and 5years was 97 percent, 92 percent, and 80 percent, respectively. Multivariate risk analysis, for the whole group, identified low ejection fraction and concomitant coronary artery bypass graft surgery as predictors of late mortality. Conclusions: Aortic valve replacement for aortic stenosis with bioprostheses in patients 70 years old or older had low perioperative mortality and morbidity and a good long term survival.

[Long-term results of mitral valve repair for ischemic mitral insufficiency]. / Resultados alejados de la cirugía reparadora de la insuficiencia mitral isquémica.

BACKGROUND: The preferred treatment for ischemic mitral insufficiency is mitral valve repair with a prosthetic ring, because it does not deteriorate left ventricular function, allowing better immediate and long-term results. AIM: To assess long-term results of mitral annuloplasty with a prosthetic ring for ischemic mitral insufficiency. PATIENTS AND METHODS: One hundred patients (68 men), with a mean age of 65.7 ± 8.6 years were included. They underwent a mitral annuloplasty with a prosthetic ring to treat ischemic mitral insufficiency, between February 1992 and May 2009. Forty four had a history of prior myocardial infarction and 46 had an evolving acute coronary syndrome. The inferior left ventricular wall was involved, exclusively or associated with an adjacent wall, in 72 cases. Coronary artery bypass grafts were performed in 92 patients and 32 required intra-aortic balloon pumping at some time during the peri-operative period. RESULTS: Operative mortality was 10% (10 patients). During follow-up 30 patients died, at an average of 39 months after surgery (range: 3-142 months). Actuarial long-term survival rates at 1, 3 and 5 years were 79%, 72% and 64.5%, respectively. Trans esophageal echocardiogram performed in the operating room showed none or minimal residual mitral insufficiency in 96% of the cases. Echocardiographic follow-up was completed in 80% of the survivors; 79% of them had no or minimal mitral insufficiency. Only one patient was re-operated on due to severe mitral insufficiency and 4 required a permanent pacemaker. CONCLUSIONS: Considering the critical illness of these patients, good long-term results were observed after treatment of ischemic mitral regurgitation performing a mitral annuloplasty with a prosthetic ring.

[Surgery of post myocardial infarction papillary muscle rupture]. / Cirugía de la rotura de músculo papilar por infarto miocárdico.

BACKGROUND: Papillary muscle rupture is a serious complication of myocardial infarction whose only treatment is surgery. AIM: To analyze our most recent surgical experience with papillary muscle rupture. PATIENTS AND METHODS: The database of our Service was reviewed for the period 1995-2005, to identify patients with papillary muscle rupture. Then, the clinical records and operating protocols were analyzed. Survival and functional class of patients were assessed. RESULTS: Twelve patients (7 men), aged 52 to 89 years, had papillary muscle rupture. They represented 2.2% of all mitral procedures for mitral insufficiency and 8.8% of mitral surgeries for ischemic mitral regurgitation, during the study period. In eight cases myocardial infarction was inferior, in three lateral and in one, anterior. In 10 patients, a mitral replacement was carried-out and in two the mitral valve was repaired. In seven patients, myocardial revascularization was performed. Mean lapse between infarction and surgery was 13.5 days (1 to 85). Two patients died in the perioperative period. Follow-up ranged from 1.7 to 120.4 months. Four patients died during follow-up, 2 due to a cardiovascular cause. Thus, at the end of follow-up 6 patients were alive. All were in functional class I-II. CONCLUSIONS: Papillary muscle rupture is an uncommon complication of myocardial infarction, with considerable operative and long-term mortality. However, survivors have good quality of life.

Cirugía de la rotura de músculo papilar por infarto miocárdico / Surgery of post myocardial infarction papillary muscle rupture

Background: Papillary muscle rupture is a serious complication of myocardial infarction whose only treatment is surgery. Aim: To analyze our most recent surgical experíence with papillary muscle rupture. Patients and Methods: The datábase of our Service was reviewed for the period 1995-2005, to identify patients with papillary muscle rupture. Then, the clinical records and operating protocols were analyzed. Survival and functional class of patients were assessed. Results: Twelve patients (7 men), aged 52 to 89 years, had papillary muscle rupture. They represented 2.2 percent of all mitral procedures for mitral insufficiency and 8.8% of mitral surgeries for ischemic mitral regurgitation, during the study períod. In eight cases myocardial infarction was inferior, in three lateral and in one, anterior. In 10 patients, a mitral replacement was carried-out and in two the mitral valve was repaired. In seven patients, myocardial revascularization was performed. Mean lapse between infarction and surgery was 13.5 days (1 to 85). Two patients died in the perioperative period. Follow-up ranged from 1.7 to 120.4 months. Four patients died during follow-up, 2 due to a cardiovascular cause. Thus, at the end of follow-up 6 patients were alive. All were in functional class III. Conclusions: Papillary muscle rupture is an uncommon complication of myocardial infarction, with considerable operative and ¡ong-term mortality. However, survivors have good quality of life.

[Cardiac myxoma: clinical characterization, diagnostic methods and late surgical results]. / Mixoma cardiaco: Caracterización clínica, métodos diagnósticos y resultados alejados del tratamiento quirúrgico durante tres décadas de experiencia.

BACKGROUND: Cardiac myxoma is the most common primary cardiac tumor. AIM: To evaluate clinical aspects, diagnostic methods and surgical outcomes in patients with cardiac myxoma. PATIENTS AND METHODS: AH patients who underwent surgical resection of a cardiac myxoma between January 1973 and December 2004 at our institution, were identified and their medical records and diagnostic data reviewed. RESULTS: Thirty seven patients identified (24 women), with a median age of 54 years (range 2-74). The most common symptom was dyspnea (51%), followed by embolism (24%) and cardiac murmurs (16%). The diagnosis was made by echocardiogram in 84% of patients. The mean tumor size was 4.9 +/- 1.3 cm. The tumor was located in the left atrium in 83% of the patients, right atrium in 8% and left ventricle in 3%. Two patients had multiple tumors. Surgical approach was transeptal in 51%, left atriotomy in 22%, combined transeptal and roof of the left atrium in 19% and right atriotomy in 8%. The tumor and its attachment base were excised in one piece. There were two operative deaths and five late deaths. The mean follow-up was 11.5 years. The 5, 10, 15 and 20 years survival was 89%, 83%, 75% and 64%, respectively. Two patients had recurrence (5.4%), at 2 and 25 years after surgery, respectively, and the recurrence free survival at 10 and 25 years was 97% and 73%, respectively. CONCLUSIONS: Dyspnea was the most common symptom and echocardiogram the main diagnostic method. Surgical treatment was highly effective, with low mortality and recurrence rate, with good long term survival.

Mixoma cardiaco: Caracterización clínica, métodos diagnósticos y resultados alejados del tratamiento quirúrgico durante tres décadas de experiencia / Cardiac myxoma: Clinical characterization, diagnostic methods and late surgical results

Background: Cardiac myxoma is the most common primary cardiac tumor. Aim: To evaluate clinical aspects, diagnostic methods and surgical outcomes in patients with cardiac myxoma. Patients and Methods: AH patients who underwent surgical resection of a cardiac myxoma between January 1973 and December 2004 at our institution, were identified and their medical records and diagnostic data reviewed. Results: Thirty seven patients identified (24 women), with a median age of 54 years (range 2-74). The most common symptom was dyspnea (51 percent), followed by embolism (24 percent) and cardiac murmurs (16 percent). The diagnosis was made by echocardiogram in 84 percent of patients. The mean tumor size was 4.9 ± 1.3 cm. The tumor was located in the ¡eft atrium in 83 percent of the patients, right atrium in 8 percent and ¡eft ventricle in 3 percent. Two patients had multiple tumors. Surgical approach was transeptal in 51 percent, left atriotomy in 22 percent, combined transeptal and roof of the left atrium in 19 percent and right atriotomy in 8 percent. The tumor and its attachment base were excised in one piece. There were two operative deaths and five late deaths. The mean follow-up was 11.5 years. The 5, 10, 15 and 20 years survival was 89 percent, 83 percent, 75 percent and 64 percent, respectively. Two patients had recurrence (5.4 percent), at 2 and 25years after surgery, respectively, and the recurrence free survival at 10 and 25years was 97 percent and 73 percent, respectively. Conclusions: Dyspnea was the most common symptom and echocardiogram the main diagnostic method. Surgical treatment was highly effective, with low mortality and recurrence rate, with good long term survival.

[Risk factors for postoperative atrial fibrillation after coronary artery bypass grafting. A prospective analysis]. / Factores determinantes en la aparición de fibrilación auricular post-cirugía de revascularización miocárdica. Un estudio prospectivo.

BACKGROUND: Atrial fibrillation (AF) is a relevant complication after coronary artery bypass grafting (CABG). However there is controversy regarding possible contributing factors. AIM: To study the incidence of AF, its risk factors and its repercussion on hospital stay and charges, in patients undergoing CABG. MATERIAL AND METHODS: We prospectively collected information from all patients undergoing CABG in our institution, including demographic, surgical and laboratory variables. Exclusion criteria were chronic AF, recent onset AF and patients who needed additional surgical procedures. The primary endpoint was the incidence of AF during the hospital stay. Secondary endpoints were hospital length of stay and hospital charges. RESULTS: We included 250 patients aged 62+/-9 years (199 males) in the analysis. Incidence of AF was 22% (54 patients). Multivariable analysis showed that age (Odds Ratio (OR) =1.10), previous CABG (OR =9.39), previous use of ACE inhibitors (OR =3.28) and aortic clamp >57 minutes (OR =3.97) were significantly associated with an increased risk of postoperative AF. Previous use of beta-blockers was associated with risk reduction (OR =0.43). Patients who developed AF had a longer hospital stay (p <0.001) and higher hospital charges (p =0.003). CONCLUSION: AF is a frequent complication in patients undergoing CABG. Risk factors are age, time of aortic clamp, previous CABG and ACE inhibitors. Beta-blockers may prevent its occurrence. Furthermore, AF has a negative impact on both hospital stay and hospital charges.

[Cryoablation of pulmonary veins as complementary treatment of atria I fibrillation in valvular surgery]. / Criocoagulación de venas pulmonares como tratamiento complementario de la fibrilación auricular en cirugía valvular.

BACKGROUND: The Cox MAZE III operation for the treatment of atrial fibrillation (AF) is complex and consumes significant operative time. Cryoablation of the pulmonary veins (CPV) is a simpler alternative for patients that require concomitant valvular surgery. AIM: To evaluate CPV in patients with AF submitted to valvular surgery. PATIENTS AND METHODS: Twenty one patients had simultaneous valvular surgery and CPV, 81 % of them had permanent AF for an average of 5 years. Twenty patients had mitral valve disease. The etiology was rheumatic in 14. Average left atrial diameter was 60 mm. In 7 patients the mitral valve was replaced, in 5 it was repaired, in 7 both mitral and aortic valve were replaced, in 1 the mitral valve was repaired and the aortic valve was replaced and in 1 only the aortic valve was replaced. A combined transeptal and superior approach was used for all patients. The CPV was performed after the valvular procedure with cryothermy at -60 degrees C for 2 minutes with two 15 mm cryoprobes applied simultaneously. RESULTS: CPV increased surgical time by 10 to 20 minutes. Operative mortality was 4.8% (1 patient). One patient developed a pericardial effusion and another a complete heart block that required a permanent pacemaker. All patients improved their functional class. At the end of an average 10.5 months of follow-up, 50% of patients were in normal sinus rhythm and 25% persisted in AF. The remaining patients were in some type of regular rhythm. CONCLUSIONS: CPV as a complementary procedure in patients with AF undergoing valvular surgery had good results to abate AF. It restored normal sinus rhythm in 50% of the cases, with low morbidity and mortality and little increment in surgical time.

Factores determinantes en la aparición de fibrilación auricular post-cirugía de revascularización miocárdica: un estudio prospectivo / Risk factors for postoperative atrial fibrillation after coronary artery bypass grafting: a prospective analysis

Background: Atrial fibrillation (AF) is a relevant complication after coronary artery bypass grafting (CABG). However there is controversy regarding possible contributing factors. Aim: To study the incidence of AF, its risk factors and its repercussion on hospital stay and charges, in patients undergoing CABG. Material and methods: We prospectively collected information from all patients undergoing CABG in our institution, including demographic, surgical and laboratory variables. Exclusion criteria were chronic AF, recent onset AF and patients who needed additional surgical procedures. The primary endpoint was the incidence of AF during the hospital stay. Secondary endpoints were hospital length of stay and hospital charges. Results: We included 250 patients aged 62±9 years (199 males) in the analysis. Incidence of AF was 22 percent (54 patients). Multivariable analysis showed that age (Odds Ratio (OR) =1.10), previous CABG (OR =9.39), previous use of ACE inhibitors (OR =3.28) and aortic clamp >57 minutes (OR =3.97) were significantly associated with an increased risk of postoperative AF. Previous use of beta-blockers was associated with risk reduction (OR =0.43). Patients who developed AF had a longer hospital stay (p <0.001) and higher hospital charges (p =0.003). Conclusion: AF is a frequent complication in patients undergoing CABG. Risk factors are age, time of aortic clamp, previous CABG and ACE inhibitors. Beta-blockers may prevent its occurrence. Furthermore, AF has a negative impact on both hospital stay and hospital charges.

Criocoagulación de venas pulmonares como tratamiento complementario de la fibrilación auricular en cirugía valvular / Cryoablation of pulmonary veins as complementary treatment of atria I fibrillation in valvular surgery

Background: The Cox MAZE III operation for the treatment of atrial fibrillation (AF) is complex and consumes significant operative time. Cryoablation of the pulmonary veins (CPV) is a simpler alternative for patients that require concomitant valvular surgery. Aim: To evaluate CPV in patients with AF submitted to valvular surgery. Patients and Methods: Twenty one patients had simultaneous valvular surgery and CPV, 81 percent of them had permanent AFfor an average of 5 years. Twenty patients had mitral valve disease. The etiology was rheumatic in 14. Average left atrial diameter was 60 mm. In 7patients the mitral valve was replaced, in 5 it was repaired, in 7 both mitral and aortic valve were replaced, in 1 the mitral valve was repaired and the aortic valve was replaced and in 1 only the aortic valve was replaced. A combined transeptal and superior approach was used for all patients. The CPV was performed after the valvular procedure with cryothermy at -60°C for 2 minutes with two 15 mm cryoprobes applied simultaneously. Results: CPV increased surgical time by 10 to 20 minutes. Operative mortality was 4.8 percent (1 patient). One patient developed a pericardial effusion and another a complete heart block that required a permanent pacemaker. All patients improved their functional class. At the end of an average 10.5 months of follow-up, 50 percent of patients were in normal sinus rhythm and 25 percent persisted in AF. The remaining patients were in some type of regular rhythm. Conclusions: CPV as a complementary procedure in patients with AF undergoing valvular surgery had good results to abate AF. It restored normal sinus rhythm in 50 percent of the cases, with low morbidity and mortality and little increment in surgical time.

Asistencia ventricular mecánica como puente al trasplante en pacientes en shock cardiogénico: Experiencia preliminar en Chile con ABIOMED BVS 5000® / Ventricular assist device as a bridge to transplant in patients with cardiogenic shock: Report of four patients

Hospitalization and death due to heart failure and cardiogenic shock is frequent and currently is increasing among the adult population. Although cardiac transplantation is the most effective treatment in patients with end-stage heart failure, its availability is limited. While waiting for transplantation, some patients become refractory to treatment and deteriorate progressively. Secondary multi-organ damage could highly compromise the transplant success and also could contraindicate it. Mechanical ventricular assist devices allow reestablishing normal cardiac output and they have been used as a bridge to recovery and transplantation. We report four patients that underwent mechanical ventricular support using the ABIOMED BVS 5000® system as a bridge for transplantation. Two patients were connected to biventricular assistance; a third patient was connected to a left ventricular support and the fourth to a right ventricular support. Three were successfully transplanted and one died of refractory non-cardiogenic shock. There were no complications related to the support system, such as infection, hemorrhage or stroke. In our experience, the ABIOMED BVS 5000® was an effective strategy as a bridge to heart transplant in patients in cardiogenic shock.

[Partial or total replacement of the aortic arch. Experience in 23 patients]. / Reemplazo parcial o total del arco aórtico. Experiencia en 23 pacientes.

BACKGROUND: Surgery of the aortic arch is a very complex procedure since it requires protective strategies for the brain, heart and rest of the body. AIM: To communicate our experience in the first 23 total or partial replacements of aortic arch. MATERIAL AND METHODS: Retrospective search in the database of the Cardiovascular Surgery Unit for patients subjected to partial or total replacement of the aortic arch since 1998. RESULTS: Between 1988 and 2002, 23 patients were operated. Seventeen had aortic dissection (10 acute and 7 chronic), five had an atherosclerotic aneurysm and one had a traumatic lesion. Thirteen patients were subjected to a replacement of the arch plus ascending aorta, six to a replacement of the arch plus descending aorta and four to a replacement of the arch, ascending and descending aorta. Seven patients had previous operation of the thoracic aorta. Arterial perfusion was done via the femoral artery, axillary artery or a combination of both. A hypothermic circulatory arrest was induced in 22; it was associated with cerebral retro perfusion alone in 8 patients, antegrade cerebral perfusion in 5; isolated or associated axillary perfusion was used in five patients. In seven, procedures on the aortic or mitral valve, or coronary artery operations were added. Operative mortality was 26%, 3 of the 8 patients operated as an emergency and 3 of 15 elective operations. There was no mortality among those without dissection and of 7 chronic dissections, one died. All patients were followed for an average of 45 months. Two patients required reinterventions on the aorta and one for colon cancer. There was one late death of unknown cause. Postoperative complications were agitation, bleeding and temporary vocal cord dysfunction. CONCLUSIONS: There is a learning curve, where more extensive operations, particularly those done as emergency or for dissections, had an increased operative risk.

Pérdida visual post cirugía cardíaca incidencia y factores de riesgo: revisión de la literatura / Visual loss after cardiac surgery: incidence and risk-factor

La pérdida de visión post cirugía cardíaca es una complicación infrecuente, pero devastadora. La incidencia reportada es variable. Realizamos una búsqueda bibliográfica de la evidencia disponible para describir su incidencia y los potenciales factores de riesgo. Se identificó una incidencia muy variable, de 0.001 por ciento a 1.3 por ciento. La causa reportada más frecuente corresponde a la neuropatía óptica isquémica. El factor de riesgo personal más significativo fue la enfermedad vascular clínica severa. Dentro de los factores de riesgo intraoperatorios, el grado de anemia, la hipotensión y la duración de la circulación extracorpórea fueron los con mayor significancia en las distintas series. Aunque la incidencia de esta complicación es baja, dada su gravedad debiera ser considerada para advertir a los pacientes con mayor riesgo preoperatorio y tratar de minimizar los factores intraoperatorios.

Lost of vision after cardiac surgery is a rare but a devastating complication. The reported incidence is variable.In order to describe it’s incidence and potential risk factors, we directed a bibliographic search of available evidence. A very variable incidence was identified, ranging from 0.001 percent to 1.3 percent. The most frecuent cause published was ischemic optic neuropathy. The most meningfull personal risk factor was clinically severe vascular disease. Among intraoperatory risk factors, the ones with the most significance in different series were anemia, hypotension and duration of extracorporeal circulation. Although the incidence of this complication is low, given it’s seriousness, it should be informed to patients with the highest preoperative risk, and intraoperatory factors should be reduced to a minimum.

Reemplazo parcial o total del arco aórtico: Experiencia en 23 pacientes / Partial or total replacement of the aortic arch: Experience in 23 patients

Background: Surgery of the aortic arch is a very complex procedure since it requires protective strategies for the brain, heart and rest of the body. Aim: To communicate our experience in the first 23 total or partial replacements of aortic arch. Material and methods: Retrospective search in the database of the Cardiovascular Surgery Unit for patients subjected to partial or total replacement of the aortic arch since 1998. Results: Between 1988 and 2002, 23 patients were operated. Seventeen had aortic dissection (10 acute and 7 chronic), five had an atherosclerotic aneurysm and one had a traumatic lesion. Thirteen patients were subjected to a replacement of the arch plus ascending aorta, six to a replacement of the arch plus descending aorta and four to a replacement of the arch, ascending and descending aorta. Seven patients had previous operation of the thoracic aorta. Arterial perfusion was done via the femoral artery, axillary artery or a combination of both. A hypothermic circulatory arrest was induced in 22; it was associated with cerebral retro perfusion alone in 8 patients, antegrade cerebral perfusion in 5; isolated or associated axillary perfusion was used in five patients. In seven, procedures on the aortic or mitral valve, or coronary artery operations were added. Operative mortality was 26%, 3 of the 8 patients operated as an emergency and 3 of 15 elective operations. There was no mortality among those without dissection and of 7 chronic dissections, one died. All patients were followed for an average of 45 months. Two patients required reinterventions on the aorta and one for colon cancer. There was one late death of unknown cause. Postoperative complications were agitation, bleeding and temporary vocal cord dysfunction. Conclusions: There is a learning curve, where more extensive operations, particularly those done as emergency or for dissections, had an increased operative risk.

Utilidad de isosorbide sublingual en la reversibilidad de la hipertensión pulmonar reactiva, en pacientes candidatos a trasplante cardíaco / Usefulness of sublingual isosorbide to assess the reversibility of pulmonary hypertension in cardiac transplant candidates

Background: Continuous infusion of short life vasodilators are employed to test reversibility of pulmonary hypertension in cardiac transplant candidates. Sublingual isosorbide administration has not been described in the literature and it might be a simpler alternative. Aim: To evaluate sublingual isosorbide administration as a test of reversibility of pulmonary hypertension in heart failure. Patients and Methods: Prospective evaluation of patients referred for cardiac transplant evaluation. Patients underwent right catheterization for hemodynamic measurements at baseline and after repeated doses of 5 mg sublingual isosorbide every 5 minutes until observing a decrease in pulmonary vascular resistance decrease or symptomatic hypotension. Results: Twenty one patients, 18 men, age 49±15 years, were studied. Fourteen (66%) were transplanted. The mean sublingual isosorbide dose was 15±5 mg. After isosorbide administration, there was a significant decrease in mean arterial pressure (80±8.5 to 71±6.6 mmHg, p <0.0001), mean pulmonary artery pressure (38±11 to 26±7.8 mmHg, p <0.0001), systemic vascular resistance (1540±376 to 1277±332 dyn*s/cm5 p <0.001), pulmonary vascular resistance (3.5±2.2 to 2,5±1.6 Wood Units, p <0.05) and transpulmonary gradient (13±7 a 10±4 mmHg, p <0.004). The cardiac output increased from 3.96±0.7 to 4.38±0.9 L/min, p=0.05. The relation between pulmonary and systemic vascular resistance before and after isosorbide was 0.17 and 0.15, respectively (p=0.04). One transplanted patient with partial reversibility of pulmonary hypertension developed acute right heart failure. Conclusions: Sublingual isosorbide administration is useful and well tolerated to evaluate the reversibility of pulmonary hypertension prior cardiac transplant.

Resultados alejados de la reparación versus reemplazo en insuficiencia mitral degenerativa / Long-term results of repair versus replacement for degenerative mitral valve regurgitation

Background: Mitral valve repair is considered better than mitral valve replacement for degenerative mitral regurgitation. Aim: To evaluate late clinical results of mitral valve repair as compared to mitral valve replacement in patients with degenerative mitral regurgitation. Patients and methods: All patients subjected to open heart surgery for degenerative mitral regurgitation between 1990 and 2002 were assessed for surgical mortality, late cardiac and overall mortality, reoperation, readmission to hospital, functional capacity and anticoagulant therapy. Eighty eight patients (48 males) had mitral valve repair and 28 (19 males) had mitral valve replacement (23 with a mechanical prosthesis). Mean age was 59.9 ± 14.8 (SD) and 61.3 ± 14.6 years, respectively. Sixty three percent of patients with repair and 50% of those with valve replacement were in functional class III or IV before surgery. Results: Operative mortality was 2.3% for mitral valve repair and 3.6% for mitral valve replacement (NS). Also, there was no statistical difference in the need of reoperation during the follow-up period between both procedures (2.3% and 0%, respectively). Ninety four percent of the replacement patients but only 26% of the repair patients were in anticoagulant therapy at the end of the follow-up period (p <0.001). Ten years survival rates were 82 ± 6% for mitral valve repair and 54 ± 11% for replacement. The corresponding cardiac related survival rates were 89 ± 6% and 79 ± 10%. At the end of follow-up, all surviving patients were in functional class I or II. Ten years freedom from cardiac event rates (death, cardiac related rehospitalization and reoperation) were 90 ± 3% for mitral valve repair and 84 ± 6% for replacement. Conclusion: Repair of the mitral valve offers a better overall survival and a better chance of freedom from cardiac events as well as need for anticoagulation 10 years after surgery.