Comparison between homografts and Freestyle® bioprosthesis for right ventricular outflow tract replacement in Ross procedures.

OBJECTIVES: Although data from large series indicate the satisfactory performance of bioprosthetic valves in the right ventricular outflow tract (RVOT), replacement of the pulmonary valve in adult patients undergoing the Ross procedure is usually performed with pulmonary allografts. We evaluated the outcomes of homografts vs. bioprosthetic RVOT replacement after the Ross procedure in adults. METHODS: Between 1996 and 2011, a total of 186 adult patients (141 male; mean age 44 ± 10 years) underwent aortic root replacement with a pulmonary autograft. The RVOT was replaced with a homograft in 113 patients and with stentless bioprostheses (Medtronic Freestyle(®)) in 73. Patients were followed for a mean of 6 years (range 1-15 years; 1106 patient years). RESULTS: Twelve patients required reintervention owing to dysfunction of the RVOT replacement, which was caused by endocarditis (n = 4), degeneration (n = 2) or stricture at the proximal suture line (n = 6). For homografts, the incidence of reintervention was 1 in 150 patient years, compared with 1 in 36 patient years for stentless bioprostheses (P = 0.007). The median gradient was 15 mmHg for the homograft group and 24 mmHg for bioprosthesis (P < 0.0001). The incidence of gradients >40 mmHg was 10-fold higher in the bioprosthetic group. CONCLUSIONS: Patients with bioprostheses in the RVOT position after the Ross procedure showed a significantly higher risk of reintervention or pulmonary valve dysfunction. The main problem, early development of a stricture at the proximal suture line, has to be solved to achieve satisfactory bioprosthetic function in the RVOT.

Secondary repair of incompetent pulmonary valves.

BACKGROUND: Secondary repair of the pulmonary valve after right ventricular outflow tract (RVOT) reconstruction is infrequently reported. This article describes possible techniques of secondary pulmonary valve repair and reports follow-up results. METHODS: Secondary pulmonary valve repairs in 7 patients (5 children and 2 adults) in our institution were reviewed. All patients presented with a severe pulmonary valve regurgitation associated with RV dilatation and dysfunction after primary RVOT reconstruction. RESULTS: The surgical techniques varied in our series, but secondary repair of the incompetent pulmonary valve was possible in all patients. Follow-up was complete, with a mean follow-up of 4.1 +/- 2.7 years. There were no operative or late deaths in our group. All valves were repaired successfully, with a mean regurgitation grade of 1.28 +/- 0.5 postoperatively. The mean transvalvular gradient was 20 +/- 4.1 mm Hg for children and 22.5 +/- 3.5 mm Hg for adults, and no significant increase of pulmonary valve regurgitation occurred during follow-up. The mean RV dilatation index (RVDI) decreased significantly from 0.85 +/- 0.25 to 0.6 +/- 0.2 for children and from 1.4 +/- 0.01 to 0.9 +/- 0.05 for adults. CONCLUSIONS: Our results showed functional recovery of the right ventricle after reoperation, with RVDI recovering to almost normal values in children. No significant regurgitation of the secondarily reconstructed pulmonary valve was observed during the 4-year follow-up period. Secondary repair for pulmonary valve incompetence after RVOT procedures might be a valuable alternative to conduit replacement.

Long-term follow-up of supra-annular pulmonary autograft aortic root replacement in patients with bicuspid aortic valve.

OBJECTIVE: The performance of the Ross procedure in the case of geometric mismatch between pulmonary autograft and a bicuspid aortic root has not yet been fully evaluated. To prevent geometrically caused autograft dysfunction, a modification of the surgical technique is necessary. METHODS: Between January 1996 and January 2007, 50 patients (33 male, 17 female; mean age 50+/-14 years; range 13-63 years) underwent replacement of a diseased bicuspid aortic valve (stenosis in 14 cases; insufficiency in 21; combined disease in 15) with a Ross procedure. The pulmonary autograft was inserted partially in supra-annular position to correct the geometric mismatch between the deeper base of the non-coronary sinus and the right/left coronary sinus. In 24 of these patients, additional tailoring of the non-coronary sinus was necessary. In eight patients the non-coronary sinus was covered with a glutaraldehyde treated autologous pericardial patch to prevent pseudoaneurysm formation. Patients were followed up 1, 2, 5 and 10 years postoperatively. RESULTS: There were no early or late deaths. There were six reoperations. One patient was reoperated because of persistent severe aortic valve insufficiency 9 months postoperatively. Three patients were reoperated for formation of subannular pseudoaneurysm, 6, 9 and 30 months postoperatively. One patient was reoperated for closure of a paravalvular dehiscence. Another patient was reoperated 1 year postoperatively because of a severe pulmonary stenosis due to excessive calcification of the bioprosthesis. Echocardiographic follow-up of the remaining patients showed no evidence of residual or recurrent pulmonary autograft regurgitation or progression of aortic root dilatation. CONCLUSION: Autograft replacement of the bicuspid aortic valve is challenging, as the geometric mismatch has to be adjusted. Valve dysfunction is avoided by a supra-annular implantation technique, but pseudoaneurysm formation at the base of the non-coronary sinus is a worrying aspect. Patch reinforcement may solve this issue.

Autograft regurgitation and aortic root dimensions after the Ross procedure: the German Ross Registry experience.

BACKGROUND: Autograft regurgitation and root dilatation after the Ross procedure is of major concern. We reviewed data from the German Ross Registry to document the development of autograft regurgitation and root dilatation with time and also to compare 2 different techniques of autograft implantation. METHODS AND RESULTS: Between 1990 and 2006 1014 patients (786 men, 228 women; mean age 41.2+/-15.3 years) underwent the Ross procedure using 2 different implantation techniques (subcoronary, n=521; root replacement, n=493). Clinical and serial echocardiographic follow up was performed preoperatively and thereafter annually (mean follow up 4.41+/-3.11 years, median 3.93 years, range 0 to 16.04 years; 5012 patient-years). For statistical analysis of serial echocardiograms, a hierarchical multilevel modeling technique was applied. Eight early and 28 late deaths were observed. Pulmonary autograft reoperations were required in 35 patients. Initial autograft regurgitation grade was 0.49 (root replacement 0.73, subcoronary 0.38) with an annual increase of grade 0.034 (root replacement 0.0259, subcoronary 0.0231). Annulus and sinus dimensions did not exhibit an essential increase over time in both techniques, whereas sinotubular junction diameter increased essentially by 0.5 mm per year in patients with root replacement. Patients with the subcoronary implantation technique showed nearly unchanged dimensions. Bicuspid aortic valve morphology did not have any consistent impact on root dimensions with time irrespective of the performed surgical technique. CONCLUSIONS: The present Ross series from the German Ross Registry showed favorable clinical and hemodynamic results. Development of autograft regurgitation for both techniques was small and the annual progression thereof is currently not substantial. Use of the subcoronary technique and aortic root interventions with stabilizing measures in root replacement patients seem to prevent autograft regurgitation and dilatation of the aortic root within the timeframe studied.

Evolution of surgical techniques for atrial septal defect repair in adults: a 10-year single-institution experience.

OBJECTIVE: We retrospectively analyzed our experience in atrial septal defect repair with varied minimally invasive surgical approaches. METHODS: From 1997 to 2006, 64 patients underwent surgical repair of atrial septal defects in our center. Patients were grouped into four groups according to the approach used; group 1 (n = 16), partial lower sternotomy; group 2 (n = 20), right anterior small thoracotomy with transthoracic clamping; group 3 (n = 4), right anterior small thoracotomy with endoaortic balloon clamping; and group 4 (n = 24), totally endoscopic approach with the use of the da Vinci surgical system (Intuitive Surgical, Mountain View, Calif). Preoperative diagnosis was a large secundum type atrial septal defect in 60 patients, primum type in 3 patients, and sinus venosus type in 1 patient. RESULTS: Complete atrial septal defect closure was verified by intraoperative transesophageal echocardiography in all patients. There was neither perioperative mortality nor major complication. Groups 3 and 4 had significantly longer aortic crossclamp, cardiopulmonary bypass, and skin-to-skin operative times than had groups 1 and 2 (P = .000). All groups had similar ventilation time, postoperative drainage, and intensive care unit and hospital stays. Only 2 patients in group 4 were converted to the minithoracotomy owing to endoaortic balloon failure. During the follow-up of 30 +/- 24.3 months, 1 patient in group 3 was reoperated on owing to significant residual shunting. CONCLUSIONS: All types of atrial septal defects can be repaired via those four different approaches as safely as can be done by the conventional technique. General complications during surgical procedures are negligible. These approaches may be considered a standard treatment and an adjunct to transcatheter treatment options in atrial septal defect repair.

The use of minimized extracorporeal circulation system has a beneficial effect on hemostasis--a randomized clinical study.

BACKGROUND: Conventional cardiopulmonary bypass (CPB) is associated with increased coagulation and fibrinolytic activity. A closed miniaturized bypass circuit (CorX) features a significantly reduced tubing set, an integrated pump, and an air removal system without a cardiotomy reservoir. In a prospective randomized trial, the effects on hemostasis were investigated while comparing CorX with conventional CPB in patients undergoing coronary artery bypass grafting. METHODS: Over a period of 1 year, 81 patients were randomly assigned either to the CorX system (n = 39, group A) or standard CPB system (n = 42, group B). Primary endpoints were platelet count, plasmin-antiplasmin complex (PAP), prothrombin fragments 1+2 (F1+F2), D-dimers, and fibrinogen. Secondary end-points were hematocrit, blood loss in the first 12 hours postoperatively, transfused packed red blood cells, and fresh frozen plasma in the first 24 hours postoperatively. In addition, we analyzed partial thromboplastin time, prothrombin time, and antithrombin III. RESULTS: After aortic declamping, PAP complex and prothrombin F1+F2 were significantly lower in group A than in group B. The difference in D-dimers between groups reached significance at 1 hour post-CPB. Hematocrit values at the end of CPB measured 26 +/- 6% in group A versus 22 +/- 4% in group B (P = .01). The rest of the observed parameters did not significantly differ between groups. CONCLUSION: Postoperative blood loss was not reduced in the present study. However, the use of the CorX system leads to a significant suppression of activation of coagulation and fibrinolytic cascades compared to conventional CPB, suggesting that miniaturized extracorporeal circuits are a step forward toward reduced imbalance of hemostasis in cardiac surgery.

Closure of atrial and ventricular septal defects should be performed by the surgeon.

Surgeons look back on 57 years of experience in the closure of atrial septal defects (ASDs) and 46 years in the closure of ventricular septal defects (VSDs). The transcatheter approaches to repair ASDs started first in the 1980s and for VSDs 8 years later. This study sought to reveal the surgical features only given by the surgical therapy and the limitation of interventional ASD and VSD closure. A variety of surgical techniques including the minimal invasive techniques for ASD or VSD closure are well described in recent publication with good results. The surgical trend is to improve the cosmetic outcome by minimizing the size of skin incision. The latest robotically assisted technique requires only four stab wound incisions. New techniques and devices have revolutionized the transcatheter technique but could not achieve the surgical ability to close all types of ASD or VSD, control arrhythmias, and correct additional valve disease or malformation. The mortality for interventional and surgical procedures approaches zero in recent publication. The residual shunting after surgical closure of ASD varies from 2% to 7.8% versus 5% to 33% after interventional closure. General complications caused by the surgical procedure are negligible; however, the shortness of hospital stay and the cosmetic appeal is an advantage of interventional ASD closure. There is no scientific comparison of surgical vs. interventional VSD closure yet.

Initial experience with a minimized extracorporeal bypass system: is there a clinical benefit?

BACKGROUND: Drawbacks of conventional cardiopulmonary bypass (CPB) are increased inflammatory response, deteriorated coagulation and systemic organ dysfunction. A closed extracorporeal circuit (CorX) features reduced foreign surface area and priming volume. Potential benefits were studied in comparing the CorX system with conventional CPB in arrested heart coronary artery bypass grafting (CABG). METHODS: Two hundred and four patients were randomly assigned either to CorX system (n = 101, group A) or a standard CPB with cardiotomy reservoir (n = 103, group B). Besides evaluation of perioperative data and routine blood samples, we focused on lung function and perioperative bleeding. Polymorphonuclear elastase (PMNE) and terminal complement complex (TCC) served to assess inflammatory response. RESULTS: Patient demographics and operative data did not differ between groups. Postoperative lung function was not significantly impaired comparing groups A and B. Intraoperative blood loss was significantly higher in group A compared with group B (1245 +/- 947 mL vs 313 +/- 282 mL, p < 0.0001) as well as the need of fresh frozen plasma. Postoperative chest drainage did not differ significantly between groups. Two patients in each group required re-exploration due to bleeding. One hour after CPB, PMNE as well as TCC were significantly lower in group A compared with group B (PMNE: 76 +/- 44 ng/mL vs 438 +/- 230 ng/mL, p < 0.0001; TCC: 16 +/- 8 IU/mL vs 29 +/- 19 IU/mL, p < 0.0001). CONCLUSIONS: The CorX system is safe and feasible in patients undergoing CABG. Despite of markedly reduced inflammatory reaction, no clinical benefit was observed.