Project description:Aortic valve surgery is the preferred procedure for replacing a damaged valve with an artificial one. The ValveTech robotic platform comprises a flexible articulated manipulator and surgical interface supporting the effective delivery of an artificial valve by teleoperation and endoscopic vision. This article presents our recent work on force-perceptive, safe, semiautonomous navigation of the ValveTech platform prior to valve implantation. First, we present a force observer that transfers forces from the manipulator body and tip to a haptic interface. Second, we demonstrate how hybrid forward/inverse mechanics, together with endoscopic visual servoing, lead to autonomous valve positioning. Benchtop experiments and an artificial phantom quantify the performance of the developed robot controller and navigator. Valves can be autonomously delivered with a 2.0±0.5 mm position error and a minimal misalignment of 3.4±0.9°. The hybrid force/shape observer (FSO) algorithm was able to predict distributed external forces on the articulated manipulator body with an average error of 0.09 N. FSO can also estimate loads on the tip with an average accuracy of 3.3%. The presented system can lead to better patient care, delivery outcome, and surgeon comfort during aortic valve surgery, without requiring sensorization of the robot tip, and therefore obviating miniaturization constraints.
Project description:BackgroundObservational studies have shown reduced perioperative bleeding in patients undergoing minimally invasive, compared with full sternotomy, aortic valve replacement. Data from randomized trials are conflicting.MethodsThis was a Swedish single center study where adult patients with aortic stenosis, 100 patients were randomly assigned in a 1:1 ratio to undergo either minimally invasive (ministernotomy) or full sternotomy aortic valve replacement. The primary outcome was severe or massive bleeding defined by the Universal Definition of Perioperative Bleeding in adult cardiac surgery (UDPB). Secondary outcomes included blood product transfusions, chest tube output, re-exploration for bleeding, and several other clinically relevant events.ResultsOut of 100 patients, three patients randomized to ministernotomy were intraoperatively converted to full sternotomy (none was bleeding-related). Three patients (6%) in the full sternotomy group and 3 patients (6%) in the ministernotomy group suffered severe or massive postoperative bleeding according to the UDPB definition (p = 1.00). Mean chest tube output during the first 12 postoperative hours was 350 (standard deviation (SD) 220) ml in the full sternotomy group and 270 (SD 190) ml in the ministernotomy group (p = 0.08). 28% of patients in the full sternotomy group and 36% of patients in the ministernotomy group received at least one packed red blood cells transfusion (p = 0.39). Two patients in each group (4%) underwent re-exploration for bleeding.ConclusionsMinimally invasive aortic valve replacement did not result in less bleeding-related outcomes compared to full sternotomy.Clinical trial registrationhttp://www.Clinicaltrialsgov . Unique identifier: NCT02272621.
Project description:Since their introduction, it has been demonstrated that minimally invasive aortic valve replacement (MIAVR) approaches are safe and effective for the treatment of aortic valve diseases. To date, the main advantage of these approaches is represented by the reduced surgical trauma, with a subsequent reduced complication rate and faster recovery. This makes such approaches an appealing choice also for frail patients [obese, aged, chronic obstructive pulmonary disease (COPD)]. The standardization of the minimally invasive techniques, together with the implementation of preoperative workup and anesthesiological intra- and post-operative care, led to an amelioration of surgical results and reduction of surgical times. Moreover, the improvement of surgical technology and the introduction of new devices such as sutureless and rapid deployment (SURD) valves, has helped the achievement of comparable results to traditional surgery. However, transcatheter technologies are nowadays more and more important in the treatment of aortic valve disease, also in low risk patients. For this reason surgeons should put new efforts for further reducing the surgical trauma in the future, even taking inspiration from other disciplines. In this review, we aim to present a review of literature evidences regarding minimally invasive treatment of aortic diseases, also reflecting our personal experience with MIAVR techniques. This review could represent a tool for a well-structured patient assessment and preoperative planning, in order to safely carrying out an MIAVR procedure with satisfactory outcomes.
Project description:AimTo evaluate the impact of minimally invasive aortic valve replacement (mini-AVR) on clinical outcomes in comparison with the gold standard.MethodsWe retrospectively reviewed the records of all patients who underwent isolated AVR at the University Hospital Center Zagreb from 2010 to 2020. Patients undergoing mini-AVR were compared with patients undergoing conventional AVR (fs-AVR). The primary outcome measure was blood product consumption. Propensity score matching was used to create a balanced covariate distribution across treatment groups. Additionally, we compared the contemporary outcomes with a historical control.ResultsThe final sample consisted of 1088 patients. In the unmatched cohorts, mini-AVR patients were younger (65±12 vs 68±10 years, P<0.001) and had lower risk profiles (EuroSCORE2 2.8±2.0 vs 3.5±3.1, P=0.003). After matching, mini-AVR patients required less blood transfusion than fs-AVR patients (270 [0-790] vs 510 [0-970] mL, P=0.029). The incidences of stroke, dialysis, new AV block, and mortality were comparable. Cross-clamp times were longer in the mini-AVR group (71 [60-87] vs 66 [53-83] minutes, P=0.013). Outcomes were improved in the contemporary mini-AVR era compared with our early mini-AVR experience across multiple metrics. Blood product consumption was reduced in the latter tercile of experience (0 [0-520] vs 500 [0-1018] mL, P<0.001), and the operation was performed more expeditiously (cross-clamp times: 63 [54,80] vs 74 [62,88] minutes, P<0.001) in comparison with earlier periods.ConclusionsWe showed that mini-AVR was associated with less blood product requirement than conventional surgery. Our data supports wider adoption of minimally invasive techniques in dedicated centers of excellence.
Project description:ObjectivesWe report on real-world safety and performance outcomes of minimally invasive rapid-deployment aortic valve replacement using the EDWARDS INTUITY Elite aortic valve system.MethodsThe study valve system was used in a European, prospective, multicentre post-market study. Various procedural, haemodynamic and clinical outcomes were evaluated through 6 months of post-implant.ResultsA total of 276 patients out of 280 (98.6%) enrolments were successfully implanted with the study valve using a minimally invasive approach between February 2016 and April 2017. Of these 276 patients, 240 (87%) underwent partial sternotomy and 36 (13%) patients underwent right thoracotomy. Mean cross-clamp time was 51.9 [standard deviation (SD): 16.0] min. From baseline to 6 months, the mean effective orifice area increased from 0.8 (SD: 0.3) to 1.8 (SD: 0.6) cm2 and the mean systolic gradient decreased from 46.0 (SD: 14.1) to 8.8 (SD: 3.7) mmHg. After 6 months, 70.7% and 26.4% of patients were in New York Heart Association class I and II, respectively. Freedom from death, major bleeding, major paravalvular leak, reoperation and device explant at 6 months were 96.0%, 98.5%, 98.8%, 99.2% and 99.2%, respectively.ConclusionsThese results demonstrate that the study valve is a safe and effective choice for patients undergoing aortic valve replacement via minimally invasive surgery.Name and registration of registryMISSION (Assessing clinical outcomes using the EDWARDS INTUITY Elite Valve System in isolated AVR using Minimally InvaSive Surgery In a EurOpean multi-ceNter, active, post-market registry). clinicaltrials.gov ID #NCT02907463.
Project description:ObjectiveMinimally invasive aortic valve replacement (MIAVR) has been demonstrated as a safe and effective option but remains underused. We aimed to evaluate outcomes of isolated MIAVR compared with conventional aortic valve replacement (CAVR).MethodsData from The National Institute for Cardiovascular Outcomes Research (NICOR) were analyzed at seven volunteer centers (2006-2012). Primary outcomes were in-hospital mortality and midterm survival. Secondary outcomes were postoperative length of stay as well as cumulative bypass and cross-clamp times. Propensity modeling with matched cohort analysis was used.ResultsOf 307 consecutive MIAVR patients, 151 (49%) were performed during the last 2 years of study with a continued increase in numbers. The 307 MIAVR patients were matched on a 1:1 ratio. In the matched CAVR group, there was no statistically significant difference in in-hospital mortality [MIAVR, 4/307,(1.3%); 95% confidence interval (CI), 0.4%-3.4% vs CAVR, 6/307 (2.0%); 95% CI, 0.8%-4.3%; P = 0.752]. One-year survival rates in the MIAVR and CAVR groups were 94.4% and 94.6%, respectively. There was no statistically significant difference in midterm survival (P = 0.677; hazard ratio, 0.90; 95% CI, 0.56-1.46). Median postoperative length of stay was lower in the MIAVR patients by 1 day (P = 0.009). The mean cumulative bypass time (94.8 vs 91.3 minutes; P = 0.333) and cross-clamp time (74.6 vs 68.4 minutes; P = 0.006) were longer in the MIAVR group; however, this was significant only in the cross-clamp time comparison.ConclusionsMinimally invasive aortic valve replacement is a safe alternative to CAVR with respect to operative and 1-year mortality and is associated with a shorter postoperative stay. Further studies are required in high-risk (logistic EuroSCORE > 10) patients to define the role of MIAVR.
Project description:ObjectiveThis study aimed to compare the outcomes of minimally invasive aortic valve replacement (MICS-AVR) versus transfemoral transcatheter aortic valve replacement (TF-TAVR) in Asian patients.MethodsWe conducted a retrospective, observational, single-center study in Japan, including cases of MICS-AVR (n = 202) and TF-TAVR (n = 248) between 2014 and 2021. In a total of 450 cases, propensity score matching was performed at a ratio of 1:1, resulting in 96 pairs. Furthermore, we performed competing-risk regression and mediation analyses to determine the treatment effect on outcomes of interests, considering death as a competing risk, and to evaluate the mediation effect of paravalvular leak (PVL) severity.ResultsThere were similar incidences of all-cause death, cardiac death, stroke and cerebral hemorrhage, and aortic valve reintervention between the 2 groups. However, the TF-TAVR cohort had a longer hospital length of stay and higher rates of significant PVL compared with the MICS-AVR cohort. Multivariable-adjusted Cox regression analyses revealed that heart failure hospitalization (hazard ratio [HR] = 0.129, 95% confidence interval [CI]: 0.038 to 0.445, p = 0.001) and permanent pacemaker implantation (HR = 0.050, 95% CI: 0.006 to 0.409, p = 0.005) favored MICS-AVR. Competing-risk regression analyses confirmed similar findings. All outcomes were unrelated to PVL severity.ConclusionsTo our knowledge, this is the first comparative study of clinical outcomes in Asian patients undergoing MICS-AVR versus TF-TAVR, revealing that MICS-AVR could be a feasible and efficient alternative to TF-TAVR. Future larger-scale randomized controlled trials are needed to validate the present results.
Project description:Minimally invasive aortic valve replacementsurgery (MIAVR) is an alternative surgical technique to conventional aortic valve replacement surgery (AVR) in selected patients. The randomised study Cardiac Function after Minimally Invasive Aortic Valve Implantation (CMILE) showed that right ventricular (RV) longitudinal function was reduced after both MIAVR and AVR, but the reduction was more pronounced following AVR. However, postoperative global RV function was equally impaired in both groups. The purpose of this study was to explore alterations in RV mechanics and contractility following MIAVR as compared with AVR.A predefined post hoc analysis of CMILE consisting of 40 patients with severe aortic valve stenosis who were eligible for isolated surgical aortic valve replacement were randomised to MIAVR or AVR. RV function was assessed by echocardiography prior to surgery and 40 days post-surgery.Comparing preoperative to postoperative values, RV longitudinal strain rate was preserved following MIAVR (-1.5±0.5?vs -1.5±0.4 1/s, p=0.84) but declined following AVR (-1.7±0.3?vs -1.4±0.3 1/s, p<0.01). RV longitudinal strain reduced following AVR (-27.4±2.9%?vs -18.8%±4.7%, p<0.001) and MIAVR (-26.5±5.3%?vs -20.7%±4.5%, p<0.01). Peak systolic velocity of the lateral tricuspid annulus reduced by 36.6% in the AVR group (9.3±2.1 vs 5.9±1.5 cm/s, p<0.01) and 18.8% in the MIAVR group (10.1±2.9 vs 8.2±1.4 cm/s, p<0.01) when comparing preoperative values with postoperative values.RV contractility was preserved following MIAVR but was deteriorated following AVR. RV longitudinal function reduced substantially following AVR. A decline in RV longitudinal function was also observed following MIAVR, however, to a much lesser extent.