Michele Murzi

Minimally Invasive and Conventional Aortic Valve Replacement: A Propensity Score Analysis

BACKGROUND The study aimed to compare the short-term results of aortic valve replacement through minimally invasive and sternotomy approaches. METHODS This is a retrospective, observational, cohort study of prospectively collected data on 709 patients undergoing isolated primary aortic valve replacement between 2004 and 2011. Of these, 338 were performed through either right anterior minithoracotomy or upper ministernotomy. With propensity score matching, 182 patients (minimally invasive group) were compared with 182 patients in conventional sternotomy (control group). RESULTS After propensity matching, the 2 groups were comparable in terms of preoperative characteristics. Cardiopulmonary bypass time (117.5 vs 104.1 min, p<0.0001) and aortic cross-clamping time (83.8 vs 71.3 min, p<0.0001) were longer in the minimally invasive group, with no difference in length of stay (median 6 vs 5 days, p=0.43), but shorter assisted ventilation time (median 8 vs 7 hours, p=0.022). Overall in-hospital mortality was identical between the groups (1.64 vs 1.64%, p=1.0). No difference in the incidence of major and minor postoperative complications and related morbidity was observed. Minimally invasive aortic valve replacement was associated with a lower incidence of new onset postoperative atrial fibrillation (21% vs 31%, p=0.04). Reduction of the complication rate was observed. Median transfusion pack per patient was higher in the control group (2 vs 1 units, p=0.04). CONCLUSIONS Our experience shows that mini-access isolated aortic valve surgery is a reproducible, safe, and effective procedure and reduces assisted ventilation duration, the need for blood product transfusion, and incidence of post-surgery atrial fibrillation.

Minimally invasive aortic valve replacement with Perceval S sutureless valve: early outcomes and one-year survival from two European centers.

OBJECTIVE The aim of our study was to evaluate the early outcomes and 1-year survival of patients undergoing minimally invasive aortic valve replacement with the Perceval S sutureless valve for severe aortic stenosis. METHODS From March 2010 to March 2013, 281 high-risk patients underwent minimally invasive aortic valve replacement with the Perceval S sutureless valve through either right anterior minithoracotomy (n = 164) or upper ministernotomy (n = 117) at 2 cardiac centers. RESULTS The overall in-hospital mortality was 0.7% (2 patients). The overall median cardiopulmonary bypass and crossclamp time was 81 minutes (interquartile range, 68-98) and 48 minutes (interquartile range, 37-60), respectively. Postoperative stroke occurred in 5 patients (1.8%). The incidence of paravalvular leak greater than 1 of 4 and atrioventricular block requiring pacemaker implantation was 1.8% (5 patients) and 4.2% (12 patients), respectively. No migration occurred, and the mean postoperative gradient was 13 ± 4 mm Hg. At a median follow-up of 8 months (interquartile range, 4-14), the overall survival was 90%. CONCLUSIONS Minimally invasive aortic valve replacement with the Perceval S sutureless valve in high-risk patients is a safe and reproducible procedure associated with excellent hemodynamic results, postoperative outcomes, and 1-year survival.

Traversing the learning curve in minimally invasive heart valve surgery: a cumulative analysis of an individual surgeon's experience with a right minithoracotomy approach for aortic valve replacement

OBJECTIVE Cumulative sum (CUSUM) analysis, first developed to assess industrial quality control, was then used to monitor cardiac surgery performance more than 10 years ago. This analysis may be more sensitive than the standard statistical tools to analyse surgical results. The aim of this study is to assess a single surgeons learning curve with right anterior minithoracotomy (RAMT) for aortic valve replacement (AVR) using risk-adjusted CUSUM curves and to compare the short- and medium-term results of these patients with a propensity-matched cohort of patients who had standard AVR (SAVR). METHODS The first 100 patients who underwent RAMT by a single surgeon were analysed, using risk-adjusted CUSUM curves. Predicted risks of failure for individual patients were derived from our institutional database, using logistic regression modelling. Perioperative death or one or more of 10 adverse events constituted failure. Finally, RAMT patients were matched to 100 SAVR patients operated by the same surgeon in the same period, using a propensity score analysis. RESULTS The authors RAMT experience was associated with a low risk of cumulative failures from the outset, and no learning curve effect was observed. A cluster of surgical failure was individuated at the end of the CUSUM curve (between patients 90 and 100). The predicted risk of failure for the study population constantly increased over the time. After propensity score matching, no baseline differences were observed between RAMT and SAVR patients. The mortality rate was similar between groups (P = 0.8). However, the RAMT group had a lower need for mechanical-assisted ventilation (P = 0.02), transfusion requirements (P = 0.001), post-operative atrial fibrillation (P = 0.01) and post-operative intensive care unit and hospital stay (P = 0.001). Three-year survival was similar between groups (RAMT 94.5% vs. SAVR 92.8%). CONCLUSIONS AVR can be safely performed through an RAMT with results comparable with the standard sternotomy technique. Patients undergoing this technique are not exposed to an increased operative risk also during the surgeons initial experience. CUSUM analysis is a valuable tool to assess the learning curve of new surgical techniques and to implement continuous performance monitoring.

Aortic Valve Replacement Through Right Anterior Minithoracotomy: Can Sutureless Technology Improve Clinical Outcomes?

BACKGROUND The impact of sutureless prosthesis on the clinical outcome in minimally invasive aortic valve replacement is still unclear. We assessed mid-term outcomes of the sutureless and conventional valves implanted through right anterior minithoracotomy. METHODS Five hundred fifteen patients undergoing primary aortic valve replacement through a right anterior minithoracotomy (269 conventional versus 246 sutureless prostheses) between 2004 and 2014 were reviewed. The most common sutured prostheses were Carpentier-Edwards Perimount and Medtronic Mosaic, and the Sorin Perceval S mainly composed the sutureless prosthesis group. One hundred thirty-three pairs of patients were propensity matched and retrospectively analyzed. RESULTS Cardiopulmonary bypass (p<0.0001) and cross-clamping (p<0.0001) times were shorter in the sutureless group (S group). We observed the same in-hospital mortality (1 versus 2; p=0.62) and incidence of postoperative stroke and pacemaker implant between the groups, but shorter duration of mechanical ventilation (6 versus 7 hours; p=0.001) in the S group. Generally, larger prostheses were implanted in the S group (p<0.0001). Follow-up was longer (p<0.0001) for sutured valves: 52 versus 15 months (overall median, 21 months). Overall Kaplan-Meier survival rate was 87.2% versus 97.0% (p=0.33) and 50% versus 100% (p=0.02) in elderly patients for sutured versus sutureless prostheses, respectively. Freedom from reoperation at follow-up (p=0.64) and transaortic gradients (12 versus 11 mm Hg; p=0.78) did not differ in the two groups. CONCLUSIONS In the present limited cohort of patients, sutureless prostheses reduced operative times for aortic valve replacement and the duration of mechanically assisted ventilation and might have influenced early and mid-term survival. Larger studies are needed to confirm our data and compare long-term outcomes.

Minimally invasive aortic valve replacement with a sutureless valve through a right anterior mini-thoracotomy versus transcatheter aortic valve implantation in high-risk patients

OBJECTIVES The aim of this study was to compare early outcomes and mid-term survival of high-risk patients undergoing minimally invasive aortic valve replacement through right anterior mini-thoracotomy (RT) with sutureless valves versus patients undergoing transcatheter aortic valve implantation (TAVI) for severe aortic stenosis. METHODS From October 2008 to March 2013, 269 patients with severe aortic stenosis underwent either RT with perceval S sutureless valves (n = 178 patients, 66.2%) or TAVI (n = 91, 33.8%: 44 transapical and 47 trans-femoral). Of these, 37 patients undergoing RT with the perceval S valve were matched to a TAVI group by the propensity score. RESULTS Baseline characteristics were similar in both groups (mean age 79 ± 6 years) and the median logistic EuroSCORE was 14% (range 9-20%). In the matched group, the in-hospital mortality rate was 8.1% (n = 3) in the TAVI group and 0% in the RT group (P = 0.25). The incidence rate of stroke was 5.4% (n = 2) versus 0% in the TAVI and RT groups (P = 0.3). In the TAVI group, 37.8% (n = 14) had mild paravalvular leakage (PVL) and 27% (n = 10) had moderate PVL, whereas 2.7% (n = 1) had mild PVL in the RT group (P < 0.001). One- and 2-year survival rates were 91.6 vs 78.6% and 91.6 vs 66.2% in patients undergoing RT with the perceval S sutureless valve compared with those undergoing TAVI, respectively (P = 0.1). CONCLUSIONS Minimally invasive aortic valve replacement with perceval S sutureless valves through an RT is associated with a trend of better early outcomes and mid-term survival compared with TAVI.

Minimally invasive right thoracotomy approach for mitral valve surgery in patients with previous sternotomy: a single institution experience with 173 patients.

OBJECTIVE This study presents a review of our experience with minimally invasive mitral valve surgery (MIMVS) in patients with a previous cardiac procedure performed through a sternotomy over a 10-year period. METHODS From November 2003 to August 2013, 173 patients (age 61.3 ± 12.4 years) underwent reoperative MIMVS through a right minithoracotomy. Previous operations were coronary artery bypass grafting (n = 49; 28.6%), a mitral valve procedure (n = 120; 70.1%), an aortic valve procedure (n = 32; 18.7%), and other operations (n = 14; 8.1%). The mean euroSCORE was 11.2 ± 3.8. The time to redo surgery was 6.9 ± 4.2 years. RESULTS Procedures were performed with central aortic cannulation in 55 patients (31.7%) and peripheral cannulation in 118 (68.3%). A transthoracic clamp was used in 58 patients (33.5%), an endoaortic balloon in 72 (41.6%), hypothermic ventricular fibrillation in 23 (13.2%), and beating heart in 20 (11.5%). Mean cardiopulmonary bypass and crossclamp times were 160 ± 58 minutes and 82 ± 49 minutes, respectively. Mitral repair was performed in 53 patients (30.6%). Forty-three patients (24.7%) had an additional cardiac procedure. Conversion to sternotomy was necessary in 2 patients (1.1%) and reoperation for bleeding in 11 patients (6.3%). Thirty-day mortality was 4.1% (n = 7). Major morbidities included stroke (n = 11; 6%) and new-onset dialysis requirement (n = 4; 2.3%). The mean blood transfusion requirement was 1.4 ± 1.1 units. Mean follow-up was 3.3 ± 2.6 years. Survival at 1, 5, and 10 years was 93.1% ± 1.9%, 87.5% ± 2.7%, and 79.7% ± 3.8%, respectively. CONCLUSIONS Reoperative mitral valve surgery can be safely performed through a right minithoracotomy with good early and late outcomes. The avoidance of extensive surgical dissection, optimal valve exposure, and low blood transfusion are the main advantages of this technique.

Full sternotomy versus right anterior minithoracotomy for isolated aortic valve replacement in octogenarians: a propensity-matched study †

OBJECTIVES Surgical aortic valve replacement (AVR) is increasingly performed in elderly patients with good perioperative outcomes and long-term survival, resulting in significant health-related quality-of-life benefits. This study aimed to evaluate the outcome of patients aged ≥ 80 years undergoing isolated AVR through a right anterior minithoracotomy (RAMT) and compare it with a full sternotomy (FS). METHODS Two hundred and eighty-three elderly patients aged 80 years or more underwent isolated AVR between February 2001 and September 2013. With propensity score matching (1 : 1), the outcomes of patients having minimally invasive surgery (RAMT) were compared with those in whom the FS approach had been employed (100 vs 100 patients). TAVRs and partial sternotomy cases were excluded from the analysis. RESULTS There were two conversions in the RAMT group. Operative times did not significantly differ in the two groups. Patients in the RAMT group received a larger-sized prosthesis (P < 0.001) and were more likely to receive sutureless valves (P < 0.001). Shorter time for extubation (P < 0.001) and shorter hospital length of stay (P = 0.005) were observed in the RAMT group. Zero vs 4 (4.0%) (P = 0.043) patients had postoperative stroke and 2 (2.0%) vs zero (P = 0.16) had a transient ischaemic attack in the RAMT versus FS group, respectively. We registered the same rate of permanent pacemaker implant (P = 0.47) and that of new-onset atrial fibrillation (P = 0.28) for both groups. Six patients died, with no significant difference for in-hospital mortality (P = 0.68). No variable had a statistically significant predictive value for in-hospital mortality. RAMT patients were more likely to be discharged home directly or via rehabilitation (P = 0.031). FS, along with four other factors, independently predicted longer hospital stay. Though the median follow-up duration was longer in the FS group (59 vs 24 months, P < 0.001), the two groups had similar survival rates at 5 years (80 vs 81%, P = 0.37). Ten factors were associated with long-term survival by Cox regression analysis, and RAMT had no statistical impact (P = 0.38). CONCLUSIONS Minimally invasive AVR through right anterior minithoracotomy can be safely performed in patients aged ≥80 years with acceptable morbidity and mortality rates. It is an expeditious and effective alternative to full sternotomy AVR and might be associated with lower postoperative stroke incidence, earlier extubation and shorter hospital stay.

Training residents in off-pump coronary artery bypass surgery: A 14-year experience

OBJECTIVE Off-pump coronary artery bypass grafting (OPCAB) is an established procedure in many cardiothoracic centers. For it to be widely applicable, however, teaching methods must be developed for surgical trainees. Early clinical outcomes and long-term survival of patients who underwent OPCAB at our institution by trainees supervised and unsupervised were compared with those of patients whose procedures were performed by senior surgeons. To evaluate evolution of training, outcomes were analyzed according to 3 different periods (1996-1999, 2000-2004, 2005-2009) and trainee seniority level. METHODS This was a retrospective, observational cohort study of prospectively collected data from 5566 consecutive patients who underwent isolated OPCAB performed by trainees (1589, 28.6%; 1111 supervised, 478 unsupervised) and by senior surgeons (3977, 71.4%). RESULTS Patients of senior surgeons were more likely to have left ventricular dysfunction (P = .001), peripheral vascular disease (P = .05), more extensive coronary artery disease (P = .001), and higher EuroSCOREs than patients of trainees. In addition, trainees were less likely to have performed urgent operations (P = .02) or reoperations (P = .03) but more likely to have operated on patients with previous percutaneous coronary intervention (P = .006). Early clinical outcomes and long-term survival were similar between groups and not related to trainee seniority, level of supervision by senior surgeon, or period during which training took place. CONCLUSIONS OPCAB is a safe and reproducible surgical technique that can be taught successfully to cardiothoracic trainees. Clinical outcomes are unrelated to level of supervision or seniority of trainees.

On-pump and off-pump coronary artery bypass grafting in patients with left main stem disease: A propensity score analysis

OBJECTIVE This study compared safety and efficacy between off-pump coronary artery bypass grafting (OPCAB), a relatively new technique, and conventional on-pump coronary artery bypass grafting (CCAB) in patients with left main stem disease. METHODS In a retrospective, observational, cohort study of prospectively collected data on 2375 consecutive patients with left main stem disease undergoing isolated CABG (1297 OPCAB, 1078 CCAB) between April 1996 and December 2009 at the Bristol Heart Institute, 548 patients undergoing OPCAB were matched with 548 patients undergoing CCAB by propensity score. RESULTS After propensity matching, groups were comparable in preoperative characteristics. Relative to CCAB, OPCAB was associated with lower in-hospital mortality (0.5% vs 2.9%; P = .001), incidence of stroke (0% vs 0.9%; P = .02), postoperative renal dysfunction (4.9% vs 10.8%; P = .001), pulmonary complications (10.2% vs 16.6%; P = .002), and infectious complications (3.5% vs 6.2%; P = .03). The OPCAB group received fewer grafts than did the CCAB group (2.7 ± 0.7 vs 3 ± 0.7; P = .001) and had a lower rate of complete revascularization (88.3% vs 92%; P = .04). In multivariable analysis, cardiopulmonary bypass was confirmed to be an independent predictor of in-hospital mortality (odds ratio, 5.74; P = .001). Survivals at 1, 5, and 10 years were similar between groups (OPCAB, 96.8%, 87.3%, and 71.7%; CCAB, 96.8%, 88.6%, and 69.8%). CONCLUSIONS OPCAB in patients with left main stem disease is a safe procedure with reduced early morbidity and mortality and similar long-term survival to conventional on-pump revascularization.

Italian multicentre study on type A acute aortic dissection: a 33-year follow-up

OBJECTIVES Despite substantial progress in surgical techniques and perioperative management, the treatment and long-term follow-up of type A acute aortic dissection (AAD) still remain a major challenge. The objective of this retrospective, multicentre study was to assess in a large series of patients the early and long-term results after surgery for type A AAD. METHODS We analysed the preoperative, intraoperative and postoperative conditions of 1.148 consecutive patients surgically treated in seven large referral centres from 1981 to 2013. We applied to each patient three different multi-parameter risk profiles (preadmission risk, admission risk and post-surgery risk) in order to compare risk factors and outcome. Long-term Kaplan-Meier survival was evaluated. RESULTS The median age was 64 years and the male population was predominant (66%). Identified diagnosis of collagen disease was present in 9%, and Marfan syndrome in 5%. Bicuspid aortic valve was present in 69 patients (6%). Previous cardiac surgery was identified in 10% of the patients. During surgery, the native aortic valve was preserved in 72% of the cases, including leaflet resuspension in 23% and David operation in 1.2%. Considering aortic valve replacement (AVR: 28%), bioprosthesis implantation was performed in 14.7% of the subjects. Neurological impairment at discharge was shown in 23% of the cases among which 21% of patients had new neurological impairment versus preoperative conditions. The overall 30-day mortality rate was 25.7%. All risk profiles remained independently associated with in-hospital mortality. During the available follow-up of hospital survivors (median: 70 months, interquartile range: 34-113, maximum: 396), cardiac-related death occurred in 7.9% of the subjects. The cumulative survival rate for cardiac death was 95.3% at 5 years, 92.8% at 10 years and 52.8% at 20 years. Severe aortic regurgitation (AR) (grade 3-4) at the time of surgery showed to be a significant risk factor for reintervention during the follow-up (P < 0.001). Among risk profiles, only the preadmission risk was independently associated with late mortality after multivariate analysis. Unexpectedly, there was no difference in freedom from cardiac death between patients with and without AVR. CONCLUSIONS Although surgery for type A has remained challenging over more than three decades, there is a positive trend in terms of hospital mortality and long-term follow-up. About 90% of patients were free from reoperation in the long term, although late AR remains a critical issue, suggesting that a thorough debate on surgical options, assessment and results of a conservative approach should be considered.