María Bueno

Hemodynamic performance of the Medtronic Mosaic and Perimount Magna aortic bioprostheses: five-year results of a prospectively randomized study

OBJECTIVE Clinical outcomes of patients undergoing aortic valve replacement may be influenced by the presence of residual gradients and patient-prosthesis mismatch. The aim of this study was to compare hemodynamic performance and clinical outcomes at 5 years after prospectively randomized porcine versus bovine aortic valve replacement. We also aimed to determine the effects of valve hemodynamics on left ventricular (LV) mass regression. METHODS A total of 108 patients undergoing aortic valve replacement were randomized to receive either the Medtronic Mosaic (MM) porcine (n=54) or the Edwards Perimount Magna (EPM) bovine pericardial prosthesis (n=54). Clinical outcomes, mean gradients, effective orifice area and LV mass regression were evaluated at 1 and 5 years after surgery. Follow-up echocardiograms were performed on 106 (98%) and 87 (92%) patients, respectively. RESULTS Preoperative characteristics were similar between groups. Mean aortic annulus diameter and mean implant size were comparable in both groups. At 1 and 5 years, mean transprosthetic gradients were lower in the EPM group: EPM 10.3±3.4mmHg versus MM 16.3 ± 7.6 mmHg (p<0.0001) and EPM 9.6 ± 3.5 mmHg versus MM 16.8 ± 8.7 mmHg (p<0.0001), respectively. Similarly, indexed effective orifice areas (IEOA) at 1 and 5 years were significantly greater in the EPM group: EPM 1.10 ± 0.22 cm(2)m(-2) versus MM 0.96 ± 0.22 cm(2)m(-2) (p<0.004) and EPM 1.02 ± 0.25 cm(2)m(-2) versus MM 0.76 ± 0.19 cm(2)m(-2) (p<0.0001), respectively. At 5 years, the incidence of patient-prosthesis mismatch (IEOA ≤0.85 cm(2)m(-2)) was significantly lower in the EPM group: EPM 22.9% vs MM 73.9% (p<0.0001). Such differences were similar when analysis was stratified by surgically measured annular size and implant valve size. During the first year after surgery, both groups demonstrated similar regression of LV mass index (MM -26.3 ± 43 gm(2) vs EPM -30.1 ± 36 gm(-2); p=0.8); however, at 5 years, regression of LV mass index was significantly greater in the EPM group: (EPM -47.4 ± 35 gm(-2) vs -4.4 ± 36 gm(-2); p<0.0001). Five-year survival was 79.6 ± 4.1% in the MM group and 94.4 ± 2.2% in the EPM group (p=0.03). CONCLUSIONS At 5 years, the EPM valve was significantly superior to the MM prosthesis with regard to hemodynamic performance, incidence of patient-prosthesis mismatch and regression of LV mass index. The hemodynamic superiority of the EPM prostheses in comparison to MM-prostheses demonstrated at 1 year, increased significantly over time.

Midterm Clinical and Echocardiographic Results With Patch Glue Repair of Left Ventricular Free Wall Rupture

Background—Left ventricular free wall rupture (LVFWR) is a dramatic complication after myocardial infarction. We present our mid-term clinical and echocardiographic results of LVFWR with an epicardial patch without cardiopulmonary bypass. Methods—From February 1993 to May 2001, 17 patients underwent surgery for LVFWR. The mean age±SD of 12 males and 5 females was 68±10 years. All patients presented for emergency surgery with cardiac tamponade confirmed on echocardiography. After opening the chest and identification of the site of rupture, a Goretex patch was fashioned and applied with enbucrilate surgical glue. Results—Effective control of bleeding was achieved in all cases. There were no on-table deaths. The operative (30 day) mortality was 23.5% (4/17). One death occurred because of patch failure, two because of cardiogenic shock, and one from pneumonia. On follow-up at a median of 2.2 years (interquartile range, 1.1 to 4.3 years), two further deaths occurred, one from myocardial infarction and another of undetermined etiology. Echocardiography did not reveal any evidence of restriction to left ventricular free wall motion. Conclusions—Patch glue repair is expedient, simple and effective; with no adverse effects on mid-term ventricular dynamics. In view of superior published results to infarctectomy and repair with extra corporeal circulation, it should be considered to be the initial procedure of choice for the surgical repair of LVFWR.

Biatrial radiofrequency ablation for atrial fibrillation: epicardial and endocardial surgical approach.

Radiofrequency energy applied by means of surgical probes permits the ablation of atrial fibrillation (AF). This study presents our initial experience on 55 consecutive cardiac patients with permanent AF with radiofrequency ablation through biatrial epicardial and endocardial surgical approach. At discharge, 8.1% of the patients had persistent AF-atrial flutter. Hospital incidence of arrhythmias were, 9% of paroxysmal atrial fibrillation, 10.9% of atrial flutter, and 34.5% of persistent atrial fibrillation. After a mean follow-up of 7 months, 83.6% patients have recovered sinus rhythm, and echocardiographic biatrial contraction was re-established in 73%. Biatrial radiofrequency ablation applied from the endocardium and the epicardium has achieved satisfactory results, without increasing the surgical risk.

Cardiac Surgery in the Elderly: Comparison Between Medium-Term Clinical Outcomes in Octogenarians and the Elderly From 75 to 79 Years

INTRODUCTION AND OBJECTIVES The age of patients undergoing cardiac surgery has increased in recent years. Our aims were to investigate the medium-term clinical outcomes of surgery in octogenarians and to compare them with outcomes in other elderly individuals of a less advanced age. METHODS We investigated early mortality, the incidence of postoperative complications, medium-term survival and factors associated with these parameters in 589 consecutive elderly patients undergoing surgery: 140 were octogenarians aged 80-87 years (group I) while 449 were aged between 75 and 79 years (group II). RESULTS The two groups were similar. There was no difference in mortality (10.0% in group I vs. 10.9% in group II) or in the incidence of postoperative complications (22% in group I vs. 30% in group II). Emergency surgery, combined surgery and pulmonary hypertension were all independent predictors of mortality and of major postoperative complications. The 5-year survival rate was 79% in group I and 65% in group II (P=.832) and the cardiac event-free survival rate was 75% in group I and 64% in group II (P=.959). Overall, 97% of patients in both groups were in functional class I or II. The additive EuroSCORE and preoperative atrial fibrillation were both associated with increased mortality during follow-up. Being an octogenarian was not a predictor (hazard ratio=0.78; 95% confidence interval, 0.51-1.21; P=.373). CONCLUSIONS In selected octogenarians, cardiac surgery gives similar results to those obtained in other elderly individuals of a less advanced age. The medium-term survival rate and quality of life are good. Pulmonary hypertension, emergency surgery and combined surgery all increased risk in these patients.

Tendencias en cirugía coronaria: cambios en el perfil del paciente quirúrgico

Introduccion y objetivos. En los ultimos anos se ha producido un aumento del riesgo en los pacientes en los que se realiza una derivacion coronaria. La mayor edad y comorbilidad son las causas involucradas con mas frecuencia. Se ha realizado un estudio retrospectivo para constatar este nuevo perfil y valorar su impacto. Pacientes y metodo. Se ha analizado la tendencia de riesgo de 1.360 pacientes en los que se realizo una derivacion coronaria consecutivamente entre 1993 y 2001 en nuestro centro. Se han considerado 3 cohortes historicas: en los anos 1993-1996, 1997-1999 y 2000-2001. Se ha estudiado la morbimortalidad y sus principales factores asociados mediante un analisis de regresion logistica. Se ha valorado la influencia de nuevas tecnicas, como la revascularizacion con injertos arteriales o la cirugia sin circulacion extracorporea. Resultados. Se ha constatado un riesgo quirurgico creciente: mayor edad, mayor frecuencia de morbilidad asociada y peor funcion ventricular. El EuroSCORE ha ratificado esta tendencia (el 2,0, el 4,0 y el 4,2% de mortalidad estimada en las cohortes respectivas; p < 0,001). Pese a ello, la mortalidad ajustada al riesgo ha descendido (el 3,7, el 2,7 y el 1,5%; p < 0,05) y la morbimortalidad global se ha mantenido (el 16,7, el 16,4 y el 13,8%; p = 0,39). El empleo de injertos arteriales y la cirugia sin circulacion extracorporea han mostrado una tendencia hacia una menor morbimortalidad hospitalaria. Conclusiones. Ha empeorado el riesgo quirurgico de los pacientes coronarios debido a una mayor edad y comorbilidad. Pese a ello, no se ha producido un aumento de la mortalidad ajustada al riesgo. El probable efecto beneficioso de la cirugia sin circulacion extracorporea y el empleo de injertos arteriales debe ser corroborado por futuros estudios.

Atrial Remodeling After Mitral Valve Surgery in Patients with Permanent Atrial Fibrillation

Abstract  Background: Mitral valve pathology is frequently associated with auricular dilatation and atrial fibrillation. Mitral surgery allows an immediate surgical auricular remodeling and besides in those cases in which sinus rhythm is reached, it is followed by a late remodeling. The aim of this study is to investigate the process of postoperative auricular remodeling in patients with permanent atrial fibrillation undergoing mitral surgery. Methods: In a prospective randomized trial, 50 patients with permanent atrial fibrillation and dilated left atrium, submitted to surgical mitral repair, were divided into two groups: Group I contained 25 patients with left auricular reduction and mitral surgery, and Group II contained 25 patients with isolated valve surgery. Both groups were considered homogeneous in the preoperative assessment. Results: After a mean follow‐up of 31 months, 46% of patients included in Group I versus 18% of patients included in Group II restarted sinus rhythm (p = 0.06). An auricular remodeling with size regression occurred in those patients who recovered from sinus rhythm, worthy of remark in Group II (–10.8% of left auricular volume reduction in Group I compared to –21.5% in Group II; p < 0.05). A new atrial enlargement took place in those patients who remained with atrial fibrillation (+16.8% left auricular volume in Group I vs. +8.4% in Group II; p < 0.05). Conclusions: Mitral surgery produces an atrial postoperative volume that decrease especially when reduction techniques are employed. Late left atrial remodeling depended on the type of atrial rhythm and postoperative surgical volume.

Recambio valvular aórtico en pacientes mayores de 70 años: determinantes de mortalidad temprana

Introduction and objectives. There is controversy regarding the risk factors associated with early death in geriatric patients undergoing aortic valve replacement. We analyzed the risks in these patients and established an accurate model for predicting in-hospital mortality. Patients and method. Univariate and multivariate analyses were made of the risk factors associated with early death in a group of 129 patients older than 70 years who underwent aortic valve replacement (May 1994-June 2001). The variables obtained by multivariate logistic regression were combined to produce an equation for the prediction of early death. The equation was tested using a receiver operating characteristic curve. Results. Univariate analysis identified four factors related to early death: NYHA III-IV (p 1.90 m 2 , 20% for < 1.40 m 2 ). The estimated mortality with the predictive model was 7.06%, which was similar to the observed mortality of 7.80% (area under the ROC curve 0.87) and better than estimates obtained with the EuroSCORE (6.5%; area under the ROC curve 0.56). Conclusions. Risk factors associated with early death after aortic valve replacement in geriatric patients include functional status, aortic regurgitation, and small body surface area. Our model based on these factors accurately predicted operative mortality in our patients. Gender, prosthesis size, and pump time were not identified as risk factors.

Trends in Coronary Artery Bypass Surgery: Changing Type of Surgical Patient

Introduction and objectives. In the last few years, the percentage of high-risk patients proceeding to coronary artery bypass surgery has increased. The most common risk factors are older age and the presence of comorbid complaints. We carried out a retrospective study to confirm this new risk profile and to evaluate its impact on surgical results. Patients and method. We analyzed the changing risk profile of 1360 patients who underwent coronary artery bypass surgery in our hospital between 1993 and 2001, divided into three historical cohorts: 1993-1996, 19971999, and 2000-2001. The main factors associated with morbidity and mortality were analyzed by logistic regression analysis. The introduction of new operative techniques, such as off-pump surgery and arterial grafting, was also evaluated. Results. The patients’ risk profile worsened over time: patients were older, comorbid complaints were more common, and ventricular function was poorer. EuroSCORE figures reflected this trend: estimated mortality in the three historical cohorts was 2.0%, 4.0%, and 4.2%, respectively (P<.001). However, risk-adjusted mortality, at 3.7%, 2.7%, and 1.5%, respectively, decreased (P<.05), and combined overall morbidity and mortality remained stable, at 16.7%, 16.4%, and 13.8%, respectively (P<.39). There was a nonsignificant tendency for arterial grafting and off-pump surgery to reduce in-hospital morbidity and mortality. Conclusions. The risk profile of patients undergoing surgery has worsened as their mean age has increased and as comorbid complaints have become more prevalent. However, there has been no simultaneous increase in risk-adjusted mortality. The potential benefits of new surgical advances such as off-pump surgery and multiple arterial grafting must be corroborated by future studies.

Ventajas de la revascularización miocárdica sin circulación extracorpórea en pacientes de riesgo

Introduction and objectives. Myocardial revascularization without cardiopulmonary bypass has been shown to reduce operative morbi-mortality. We report our recent experience with this novel technique in order to evaluate its theoretical advantages in comparison with conventional surgery. Patients and methods. This retrospective analysis included 547 consecutive patients undergoing isolated myocardial revascularization from December 1997 through November 2000. One hundred twenty-one offpump patients were compared to 426 undergoing cardiopulmonary bypass. Logistic regression analysis was performed to find predictors of mortality, transfusion, postoperative atrial fibrillation and length of hospital stay. Results. Off-pump patients were at greater risk: they were older, with a lower ejection fraction and a higher prevalence of unstable angina, heart failure and associated comorbidity. Off-pump surgery reduced transfusions (1 ± 1 vs 1,9 ± 2 blood units; p < 0.0001) and postoperative hospital stays (8.9 ± 5 vs 11,3 ± 7 days; p < 0.001). The off-pump group showed a trend toward reduced morbidity but the technique did not decrease hospital mortality. Cardiopulmonary bypass was an independent predictor of blood transfusion and longer hospital stay. Short-term follow-up revealed no significant differences in recurring angina or patency rates. Conclusions. Off-pump coronary bypass surgery is a good option in high-risk patients because it reduces the incidence of perioperative transfusion and the length of hospitalization. Furthermore, it showed a trend toward reduced morbidity. Mortality was not significantly higher in spite of the higher risk of the patients. Long-term longitudinal follow-up is mandatory to assess the true effectiveness of this technique.

Aspirin plus clopidogrel versus aspirin alone for the prevention of coronary artery bypass graft occlusion: angiographic and clinical results of a randomized study

Prevalence of graft occlusion is high after coronary artery bypass grafting (CABG). Routine use of aspirin after CABG reduces graft failure and ischemic complications. The benefit of concomitant clopidogrel administration remains a controversial issue.