Emmanuel Villa

The Italian study of the Mitroflow postoperative results (ISTHMUS): a 20-year, multicenter evaluation of Mitroflow pericardial bioprosthesis

OBJECTIVE A multicentre experience with the Mitroflow pericardial bioprosthesis has been evaluated longitudinally over a 20-year period. METHODS From 1988 through 2008, 1591 patients (mean age, 75.3±6.8 years, and 60.1% female) from 12 centres had a Mitroflow in the aortic position. Concomitant coronary artery bypass was performed in 41.9% (n=666) of patients, urgency/emergency surgery in 9.5% (n=152) and replacement of degenerated prosthesis in 2.3% (n=36). Follow-up (7.447 patient-years) was 99.2% complete. Median follow-up was 61.9 months (interquartile range (IQR) 30.8-90.9 months). The study was carried out following American Association for Thoracic Surgery/Society for Thoracic Surgeons/European Association for Cardio-Thoracic Surgery (AATS/STS/EACTS) Guidelines for reporting valve morbidity and mortality. RESULTS The early (30-day) mortality was 6.5% (n=104). Actuarial survival rates at 10, 15 and 18 years were 53%, 34% and 27%, respectively (2.2 patient/year). Re-operation was required in 96 patients (5.9%), of whom 59 patients (3.7%) for structural valve degeneration. Actuarial freedom from prosthetic valve degeneration at 18 years was 65.5% (78% in patients>70 years) with a linearised rate of 1.4 patient/year (0.8 patient/year in patients>70 years). At 18 years, freedom from embolism was 82% (0.9 patient/year), freedom from valve endocarditis was 89% (0.6 patient/year) and freedom from bleeding episodes was 95% (0.2 patient/year), respectively. CONCLUSIONS This independent multicentre study indicates that the Mitroflow pericardial bioprosthesis provides favourable long-term postoperative results with a low rate of valve-related events and need of re-intervention, particularly in patients older than 70 years.

Inflammatory cytokines in pediatric cardiac surgery and variable effect of the hemofiltration process.

Cardiac surgery with cardiopulmonary bypass (CPB) elicits an inflammatory response and has a multitude of biological consequences, ranging from subclinical organ dysfunction to severe multiorgan failure. Pediatric patients are more prone to have a reaction that can jeopardize their outcome. Cytokines are supposed to be important mediators in this response: limiting their circulating levels is, therefore, appealing. We investigated the pattern of cytokine release during pediatric operation for congenital heart anomalies in 20 patients, and the effect of hemofiltration. Tumor necrosis factor a (TNF-α) was elevated after anesthesia induction and showed significant decrease during CPB. Hemofiltration reduced its concentration, but the effect disappeared on the following day. Interleukin-1 (IL-1) increased slowly at the end of CPB and hemofiltration had no effect. Interleukin-6 (IL-6) showed a tendency toward augmentation during rewarming and hemofiltration did not significantly affect the course. Soluble interleukin-6 receptor (sIL-6r) had a pattern similar to TNF-α, but hemofiltration had no effect. On the other hand, interleukin-8 (IL-8) behaved like IL-6. Our findings suggest that baseline clinical status, anesthetic drugs, and maneuvers before incision may elicit a cytokine response, whereas rewarming is a critical phase of CPB. Hemofiltration is effective in removal of TNF-α, but its role is debatable for the control of IL-1, IL-6, sIL-6r and IL-8 levels.

Factors affecting left ventricular remodeling after valve replacement for aortic stenosis. An overview

Although a small percentage of patients with critical aortic stenosis do not develop left ventricle hypertrophy, increased ventricular mass is widely observed in conditions of increased afterload. There is growing epidemiological evidence that hypertrophy is associated with excess cardiac mortality and morbidity not only in patients with arterial hypertension, but also in those undergoing aortic valve replacement. Valve replacement surgery relieves the aortic obstruction and prolongs the life of many patients, but favorable or adverse left ventricular remodeling is affected by a large number of factors whose specific roles are still a subject of debate. Age, gender, hemodynamic factors, prosthetic valve types, myocyte alterations, interstitial structures, blood pressure control and ethnicity can all influence the process of left ventricle mass regression, and myocardial metabolism and coronary artery circulation are also involved in the changes occurring after aortic valve replacement. The aim of this overview is to analyze these factors in the light of our experience, elucidate the important question of prosthesis-patient mismatch by considering the method of effective orifice area, and discuss surgical timings and techniques that can improve the management of patients with aortic valve stenosis and maximize the probability of mass regression.

Mitral Valve Repair: Is There Still a Place for Suture Annuloplasty?

Prosthetic ring annuloplasty is considered the gold standard technique for mitral valve repair, but it has been associated with some drawbacks. Suture annuloplasty is less expensive and may have some physiopathologic advantages. We reviewed the literature to assess clinical results of mitral suture annuloplasty. Thirteen series, each reporting more than 50 patients and published in the last 10 years, were included in the analysis. They comprised 1,648 patients with cumulative follow-up of 5,607 patient-years. Our review suggests that suture annuloplasty is a safe procedure, but a trend toward recurrence of annular dilatation with time was reported. In selected cases, suture annuloplasty is effective, and its mid-term clinical results are encouraging and compare well with those of prosthetic ring repair series. The quality of the results varies according to the particular annuloplasty technique used and to the mitral valve pathology treated. Recent technical modifications have been found to decrease the incidence of repair failure and promise to improve the reproducibility of the procedure. Further investigations are warranted to better assess the long-term results of suture annuloplasty, and to determine whether its theoretical functional advantages translate into a real clinical benefit.

Perceval Sutureless Valve in Freestyle Root: New Surgical Valve-in-Valve Therapy

Aortic root replacement with biological conduit (homograft, autograft, or xenograft) is a valuable tool, but biological valves are often prone to degeneration. Reoperations usually require root removal and repetition of the Bentall procedure to maintain the same orifice area. A less radical option is to limit replacement to the valve. In cases of calcified or very small roots, standard valve implantation cannot be performed, and bailout with a sutureless valve may be a particularly useful option. Here we have described a case of leaflet rupture in a calcified small Freestyle root (Medtronic Inc, Minneapolis, MN) in which we performed a valve-in-valve (V-in-V) procedure with a Perceval-S prosthesis (Sorin Group, Saluggia, Italy).

An alternative technique for non-infective paraprosthetic leakage repair

Severe paravalvular leak is generally a reason for the repetition of valve replacement surgery. On the contrary management of patients with mild and moderate defects is controversial. Long-term prognosis may be negatively affected if non-surgical strategy is adopted also in less symptomatic patients. The proposed technique of leak closure preserves the implanted prosthesis and may be useful in non-infective mild and moderate detachments. It may safely extend surgical treatment to less symptomatic patients suffering from this surgical complication.

Chordal plication and free edge remodeling for mitral anterior leaflet prolapse repair: 8-year follow-up

BACKGROUND Chordal suture plication and free edge remodeling represent a personal technique for the repair of anterior leaflet prolapse. We report the results of an 8-year experience. METHODS Sixty-one patients with degenerative mitral regurgitation caused by prolapse of the anterior leaflet (11) or both leaflets (50) underwent anterior leaflet prolapse repair. Twenty patients who had associated cardiac procedures are included. RESULTS There were two perioperative deaths. Postoperative mitral regurgitation fell to 0.4 +/- 0.7 versus 3.7 +/- 0.4 preoperative (p < 0.0001). Mean follow-up was 40.5 months. There were 3 late deaths and 3 mitral reoperations (1 of 3 repairs, 2 of 3 replacements). Thromboembolism and endocarditis occurred in 1 patient each. Actuarial overall survival, freedom from cardiac death, and freedom from mitral reoperation at 92 months were 85.1% +/- 7.9%, 88.9% +/- 7.7%, and 94.6% +/- 3.0%, respectively. CONCLUSIONS Our technique of anterior leaflet prolapse repair appears effective, safe, and durable at mid- to long-term follow-up, and may be used in the presence of extensive disease of both leaflets.

Video-assisted thoracoscopic clipping of patent ductus arteriosus: close to the gold standard and minimally invasive competitor of percutaneous techniques.

Objective To review our 12-year experience in video-assisted thoracoscopic surgery (VATS) for patent ductus arteriosus. Methods VATS was performed in 743 patients. Three groups were compared: 24 low-birth-weight infants (LBWIs), 676 children between 2.5–25 kg and 43 boys > 25 kg. A diameter of > 8 mm was the main contraindication. For 85 consecutive patients, hospital stay underwent cost analysis. Results Median age was 1.6 years (range 5 days–33 years) and median weight 9.0 kg (range 1.2–65 kg). Mortality was nil. Median operative time was 20 min and hospital stay 2 days. Residual patency at discharge was 0% in LBWIs, 0.7% in children, and 4.7% in boys (P = NS) and 0, 0.3, and 4.7% at follow-up (P = 0.001). Persistent recurrent laryngeal nerve dysfunction was recorded in 4.2% of LBWIs, 0.3% of children and 0% of boys (P = 0.012). Total mean cost was 5954 ± 2110. Conclusions The success rate of VATS clipping compares favorably with the thoracotomic approach but without chest wall trauma and it may have a very favorable cost-effective therapeutic balance compared to transcatheter techniques.

Medium-term results of systematic off-pump coronary surgery performed by trainee surgeons §

OBJECTIVE Our unit has used off-pump coronary artery bypass (OPCAB) surgery since 1998, and has consequently developed teaching methods for surgical trainees. This study aimed to compare the medium-term results of OPCAB performed by experts or supervised trainees. METHODS We retrospectively analysed the data relating to 1333 OPCAB operations performed between January 1998 and January 2006 (mean patient age: 65.3 + or - 13; M/F ratio: 2.9), and compared the medium-term outcomes of the 977 (73.3%) carried out by three expert surgeons (group A) with the remaining 356 (26.7%) carried out by four supervised trainees (group B). RESULTS There were no preoperative differences in patient age, gender, angina class, operative priority, extent of coronary artery disease, the presence of a recent myocardial infarction or left main stenosis or European System for Cardiac Operative Risk Evaluation (EuroSCORE) between the two groups. Thirty-day mortality was 1% in group A and 0.6% in group B (p=0.43), and 4-year actuarial survival, respectively, 97.4 + or - 1.1% and 94.3 + or - 4.1% (p=0.41); the freedom from new re-vascularisation rates in the two groups were, respectively, 96 + or - 0.7% and 95.3 + or - 1.4% (p=0.3). CONCLUSIONS The results of this study reflect our units long experience of OPCAB surgery and that its successful re-engineering towards the systematic use of OPCAB was feasible. They also show that, in this context, teaching OPCAB surgery is safe in a non-selected cohort of patients, and that the medium-term outcomes of the patients operated on by trainee or expert surgeons are similar.

Sutureless Aortic Valve Replacement International Registry (SU-AVR-IR): design and rationale from the International Valvular Surgery Study Group (IVSSG)

BACKGROUND Sutureless aortic valve replacement (SU-AVR) is an innovative approach which shortens cardiopulmonary bypass and cross-clamp durations and may facilitate minimally invasive approach. Evidence outlining its safety, efficacy, hemodynamic profile and potential complications is replete with small-volume observational studies and few comparative publications. METHODS Minimally invasive aortic valve surgery and high-volume SU-AVR replacement centers were contacted for recruitment into a global collaborative coalition dedicated to sutureless valve research. A Research Steering Committee was formulated to direct research and support the mission of providing registry evidence warranted for SU-AVR. RESULTS The International Valvular Surgery Study Group (IVSSG) was formed under the auspices of the Research Steering Committee, comprised of 36 expert valvular surgeons from 27 major centers across the globe. IVSSG Sutureless Projects currently proceeding include the Retrospective and Prospective Phases of the SU-AVR International Registry (SU-AVR-IR). CONCLUSIONS The global pooling of data by the IVSSG Sutureless Projects will provide required robust clinical evidence on the safety, efficacy and hemodynamic outcomes of SU-AVR.