Erika Correa Vrandecic

Retrospective clinical analysis of stented vs. stentless porcine aortic bioprostheses

OBJECTIVE The study was designed to compare hemodynamic performance, structural failure and survival of patients undergoing aortic valve replacement (AVR) with a composite aortic stented or stentless porcine bioprosthesis. METHODS From January 1990 to June 1999, the clinical data of 725 patients undergoing AVR with stented porcine aortic bioprosthesis were reviewed. We defined two groups of patients with similar clinical characteristics: 202 patients receiving aortic stented and 205 patients stentless valves. The two patients groups were similar in age, sex, valve lesion, valve size, preoperative New York Heart Association (NYHA) class status and follow-up. RESULTS The number of patients available for follow-up, excluding hospital and late mortality, reoperations and patients lost to follow-up, was 157 for the stented and 175 for the stentless group. There was a higher incidence of rheumatic heart disease in the stented (59%) vs. stentless group (44%), (P=0.003). Fewer patients had prior aortic bioprosthetic dysfunction in the stented (7.6%) compared to the stentless group (25%) (P<0.001). The mean intensive care unit stay, hospital mortality and late mortality were similar (P, NS). The total complication rate was higher in the stented (12%) than the stentless (3.4%)(P=0.005). Valve related death was higher in the stented (2.5%) than the stentless (0%) (P=0. 049). Postoperatively, the aortic effective orifice area (AEOA) was larger (P<0.001) and the transvalvular peak and mean gradients were lower in the stentless group (P<0.001). The leaflet tissue degeneration analysis was 8.0% in patients at risk for stented and 0. 6% for stentless (P=0.001). Actuarial analysis disclosed no statistical difference in patient survival between groups (P=0.18). Reoperations were less frequent in the stentless group (P=0.010). CONCLUSIONS Hemodynamic benefits in the stentless group were evident and expressed by larger AEOA, lower gradients, better left ventricular remodeling with significant decrease of the left ventricular mass. Lower complication rates, lower reoperation rates, less leaflet tissue degeneration, and lower valve related mortality rates were seen in the stentless group. A controlled clinical comparison trial with longer follow-up will be required to confirm these clinical and hemodynamic benefits.

Fontan operation: a technique in evolution.

OBJECTIVES Recent experimental flow studies based on angiography and magnetic resonance have shown that total cavopulmonary anastomosis (TCPA) is a valid concept for surgical treatment of many congenital heart defects, but there is not agreement of the best surgical arrangement. Our purpose is to analyze the immediate results with three different techniques of TCPA. METHODS We sought to analyze retrospectively all TCPA realized from January 2005 to July 2008; there were 40 patients, all with previous Glenn anastomosis, with mean age of 6.4 +/- 3.2 years. Three different techniques were employed: Group 1 (G1) lateral tunnel, Group 2 (G2) extracardiac conduits, Group 3 (G3) intracardiac conduit directed to the left pulmonary artery. All patients had a fenestration done. RESULTS G1 had 11 patients, G2 10 patients and G3 19 patients. Preoperative data were similar in the 3 groups (P>0.05). Surgical mortality was higher in Groups 1 and 2 (9.1% and 10%) compared to Group 3 (0%) but there was no statistical significance (P=0.3841). Pleural effusion was absent in Group 3 (0%), which was statistically significant in relation to the other groups (P=0.0128). The hospitalization time was also significantly lower in G3 (8 days) in relation to G1 (18 days) and G2 (13 days) (P=0.0164). CONCLUSION Intracardiac TCPA was associated with lower postoperative morbidity and is currently our preferred technique.

Porcine stentless valve/bovine pericardial conduit for right ventricle to pulmonary artery

BACKGROUND AND OBJECTIVES We assessed the long-term outcome of a glutaraldehyde-preserved bovine pericardial conduit containing a stentless composite porcine aortic valve. METHODS Between November 1985 and May 1995, 33 stentless porcine valves attached to bovine pericardial conduits were used in 33 patients with complex congenital cardiac malformations. These patients required a conduit between the right ventricle and the pulmonary artery because of an absent or inadequate pulmonic artery. All patients were approached by midsternotomy. One patient with pulmonic atresia and an interventricular septal defect required left thoracotomy for ligation of collaterals. RESULTS Of the initial 33 patients, clinical follow-up was performed in 23 discharged patients (70%) for 1.7 to 10.5 years. The echo-Doppler analysis performed in each of the 23 followed patients showed excellent conduit and valve function in all but 4 patients, in whom a valve gradient of 60 mm Hg was noted. There was no tissue structural failure noticed in this study. CONCLUSIONS The SJM Biocor (Belo Horizonte, Brazil) bovine pericardial stentless valved conduit performed well as a substitute for the right ventricle to pulmonary artery connection.

Surgical technique of implanting the stentless porcine mitral valve

The new stentless porcine mitral valve was developed to serve as an anatomically correct substitute for a diseased mitral valve. Extensive acute animal experimentation was performed, and from this the logical sequence for selecting the correct valve size and the specific technique for implanting it were determined. The following are the major steps to successfully implant a mitral stentless valve: First, mitral valve complex analysis must be done to determine the correct procedure to be performed and the feasibility of using the stentless mitral valve. Second, the correct size of stentless mitral valve must be chosen. Third, the papillary muscle anatomy must be assessed to determine the site and number of sutures necessary for securely holding the new origin of the new chordae. Fourth, the papillary muscle sutures must be anchored to the free pericardial edge of the new chordal origin. Fifth, the chordal alignment with both trigonal areas must be perfect. Sixth, the annulus may be sutured using either continuous or interrupted sutures. Perioperative echocardiography, preferably transesophageal echocardiography, should be done in every patient. Although reoperation was necessary in 5 patients (non-valve-related), the results in 74 patients (3 early and 3 late non-valve-related deaths excluded) followed up for at most 26 months (mean, 14 months) have been excellent. The quality of the results obtained in this initial clinical trial has reinforced our current preference for this valve in patients requiring mitral valve replacement. Longer follow-up is required to confirm that these good results continue.

Estratégia cirúrgica na transposição das grandes artérias associada à obstrução do arco aórtico

Objective: Our results on the transposition of the great arteries with aortic arch obstruction were analyzed to establish our present protocol.

Porcine mitral stentless valve mid-term clinical results.

OBJECTIVES Time testing is essential with any valvular procedure, especially when a new concept is introduced such as the mitral stentless valve. Our purpose is to evaluate the results obtained over 4 years with this operation, particularly to attest the impact of preservation of annulo ventricular continuity on the long term results of these patients. METHODS From March 1992 to August 1996, 120 patients had their mitral valves replaced with a porcine stentless mitral valve. The observation period was 54 months with total patients follow-up of 3424 months with a mean of 28.5 months. The age ranged from 11 to 72 years (mean 35.22 +/- 14.98). There were 73 females (60.8%) and 47 males (39.2%). The predominant etiology was rheumatic heart disease. Associated procedures were performed in 12 patients (10%), and the great majority of the patients were in functional class III and IV (NYHA). RESULTS Hospital mortality occurred in seven patients (5.83%) non valve related except for one early case of endocarditis. Early reoperation related to technical failure were necessary in 4 patients without mortality. Follow-up was accomplished in 101 patients and ranged from 2 to 54 months. Late reoperations were required in 16 patients (nine due to mitral insufficiency, five because of endocarditis and two for mitral stenosis). Most reoperations were related to technical failure. Among the 82 patients presently in control, 72 showed a competent mitral stentless valve, eight with stable mild mitral regurgitation and in two a decreased mitral orifice. Hemodynamic performance of the valve has been excellent in this group, particularly in patients with left ventricular dysfunction. CONCLUSION Although technical complexity remains the main cause of reoperations with this valve, experience has shown that it not only provides preservation of the left ventricular function but also promised significant increase of the ejection fraction in patients with poor left ventricular function.

Estratégia cirúrgica na transposicão das grandes artérias com septo interventricular intacto após o período neonatal

OBJECTIVE To assess the surgical results in patients with transposition of the great arteries and intact ventricular septum undergoing surgery after the neonatal period. METHODS From January 1998 to March 2004, 121 children with transposition of the great arteries with intact ventricular septum were treated, 29 (24%) of whom after the neonatal period. Selection for surgical treatment was based on echocardiographic assessment by use of the calculation of left ventricular mass and configuration of the ventricular septum. Of the 29 children, 12 were selected for primary anatomic correction, 12 for 2-stage correction after surgical preparation of the left ventricle, and 5 underwent atrial correction. RESULTS In the group undergoing primary anatomic correction, one (8.3%) patient died at the hospital due to sepsis. In the group undergoing 2-stage correction, 5 patients underwent slow preparation with correction 3-6 months after the first stage, 4 of whom died after the first stage. This fact caused a change in our protocol, with adoption of the rapid preparation technique in the other 7 patients, of whom all achieved the second stage. Of the 8 children undergoing the second stage, one died at the hospital and another died later. Late clinical evolution of the children in both groups is excellent. CONCLUSION The echocardiographic selection allowed a safe choice of the best surgical approach for patients with transposition of the great arteries and intact ventricular septum after the neonatal period.