María José Dalmau

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.

Takotsubo cardiomyopathy after elective mitral valve replacement

Takotsubo cardiomyopathy is a syndrome characterized by transient acute left ventricular dysfunction, electrocardiographic changes that can mimic acute myocardial infarction and minimal release of myocardial enzymes in the absence of obstructive coronary artery disease. Reports of Takotsubo syndrome after cardiac surgery are exceptional. We describe a case of Takotsubo cardiomyopathy in a 68-year-old woman after elective mitral valve replacement. Takotsubo syndrome should be considered in the differential diagnosis of patients presenting cardiogenic shock after cardiac surgery.

Surgical ablation of permanent atrial fibrillation by means of maze radiofrequency: mid-term results.

Abstract  Background: The maze procedure can be performed surgically with radiofrequency, generating transmural ablation lines. We report our experience with a biatrial pattern of lesions based on the use of epicardial and endocardial radiofrequency ablation in an effort to minimize maze procedure. Method: In 85 patients undergoing cardiac surgery for established permanent atrial fibrillation (>3 months), a biauricular pattern of epicardic–endocardic maze lesions was performed. The main surgical procedures were diverse: 42 mitral valve surgeries, 7 mitrotricuspid valves, 18 mitroaortics, 4 mitroaortic and tricuspids, 2 aortic valves, 3 CABGs, 5 CABG and valve procedures, and 4 atrial septal defects. The mean age of the patients was 61 ± 12 (range 39–78). The mean duration of atrial fibrillation was 5.8 years (range 0.3 to 24). Results: Sixty‐two (72.9%) patients presented postoperative supraventricular arrhythmia. Hospital mortality was seen in five patients (5.8%). Two patients died after a 12‐month mean follow‐up (range 2 to 32). A total of 14.1% of patients remained with their previous atrial fibrillation and 85.9% recovered and maintained sinus rhythm, with two patients having a permanent pacemaker. A total of 56% patients have been followed‐up for a period of more than 6 months, and among them prevalence of sinus rhythm is 87.5%. Echocardiography detected biauricular contraction in 65% of them. After analyzing the data, factors involved in postoperative recurrence of atrial fibrillation after radiofrequency surgery were oldness of the atrial fibrillation (p < 0.01) and pre and postoperative left auricle volume (p < 0.04). Conclusion: Intraoperative radiofrequency has permitted us to perform the maze procedure in a simple way, with a low surgical morbid‐mortality. We have obtained an 85.9% electrographic effectiveness and a 65% recovery of atrial contraction. Postoperative incidence of arrhythmia is the main postoperative problem.

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.

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.

Bone cement implantation syndrome during spinal surgery requiring cardiac surgery.

During a posterior segmental spinal fusion procedure, a 71-year-old woman developed cardiac and pulmonary embolism characterized by nonsustained ventricular tachycardia during cement injection, rapid and severe hypoxemia, and hemodynamic instability. Management included exploratory cardiotomy under cardiopulmonary bypass and removal of the emboli from the pulmonary vessels. Postoperative recovery was successful, and the patient was discharged without sequelae. We discuss the pathophysiology of bone cement implantation syndrome during spinal fusion, possible causative factors, and treatment alternatives.

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.

Extensive dissection in left coronary artery

A 32-year-old male with an acute coronary syndrome. Early coronary angiography showed an occlusion at the middle level of the left anterior interventricular artery. A primary percutaneous transluminal coronary angioplasty implanting a stent due to sub-optimal balloon results, obtaining a good angiographic result (TIMI III flow), and the patient was asymptomatic. Angiographic control was performed at 24 h showing extensive coronary dissection at the left main, left anterior descending, first diagonal, circumflex, first and second obtuse marginal arteries (Fig. 1). The probable mechanism was progressive spontaneous retrograde dissection from a segment of the stent. Four urgent coronary artery bypass grafts were performed. The postoperative course was uneventful, and the patient was discharged on the 10th day. After 2 years of follow-up, the patient is asymptomatic. European Journal of Cardio-thoracic Surgery 20 (2001) 1232