Robotic-assisted Mitral Valve Repair Research Articles

Is concomitant tricuspid valve repair in patients undergoing robotic mitral valve repair safe and effective?

ObjectivesRobotic-assisted mitral valve repair (MVr) is a well-established procedure for management of degenerative mitral valve disease. Limited data regarding concomitant robotic-assisted tricuspid valve repair (TVr) is available. This review investigates prevalence and outcomes of concomitant robotic-assisted mitral and tricuspid valve repair. MethodsFrom 2014 to 2022, 839 patients underwent robotic-assisted MVr, including 76 patients with moderate or greater tricuspid regurgitation and/or tricuspid annular dilatation ≥40 mm. Among the 76 patients, 19 (25%) underwent isolated MVr and 57 (75%) had concomitant mitral and tricuspid valve repair. Outcome data between the 2 groups were analyzed. ResultsIn the MVr/TVr group, tricuspid regurgitation grades were mild in 4 (7%) patients, moderate in 44 (77%) and severe in 9 (15.7%). Significant tricuspid annular dilatation ≥40 mm was present in all patients. In the isolated MVr group, 3 (15.7%) patients had mild tricuspid regurgitation and 16 (84.2%) had moderate tricuspid regurgitation with significant tricuspid annular dilatation present in only 6 patients. Cardiopulmonary bypass and crossclamp time were 130.6 and 91 minutes versus 85 and 55.4 minutes for robotic MVr/TVr group versus MVr group, respectively (P < .05). The intensive care unit and hospital length of stay were similar: 27.7 versus 27.7 hours and 4.4 versus 4.2 days for MVr/TVr versus MVr (P = .24), respectively. There were no perioperative deaths or heart block in either group. Survival and freedom from reoperation with median follow-up of 16 and 46 months for MVr/TVr and MVr groups, respectively were 100%. ConclusionsConcomitant robotic-assisted tricuspid valve repair for functional regurgitation can be safely and effectively performed at the time of mitral valve repair with excellent short-term morbidity and mortality results.

Robotic Mitral Valve Repair: Impact of Experience on Results and Complex Mitral Disease Treatment.

Background/Objectives: Robotically assisted mitral valve (MV) surgery is the least invasive surgical approach to the MV. The aim of the present study is to report our experience with robotically assisted MV repair, trying to define how experience could impact on postoperative results. Methods: This is a retrospective study on 144 patients who underwent robotic MV repair from November 2011 to March 2023. Patients were divided in two groups: Group 1, including 39 patients (November 2011-January 2013) operated using the Da Vinci Si system, and Group 2, including 105 patients operated (February 2020-March 2023) using the new Da Vinci Xi system. Results: Mean age was 58 ± 10 years. Increased use of external aortic clamp was observed in Group 2. A significant reduction of surgical times was observed: cardiopulmonary bypass time was 155 ± 44 min in Group 1 and 121 ± 36 min in Group 2 (p = 0.002), whereas cross-clamp time was 112 ± 25 min in Group 1 and 68 ± 39 min in Group 2 (p < 0.001). In-hospital mortality was 0.7%, and 10-year survival was 96 ± 2%. Freedom from reoperation was 100%. A higher percentage of complex and most complex MV repairs were performed in Group 2 (36% in Group 1 vs. 52% in Group 2, p = 0.001). Conclusions: Robotic-assisted MV repair is associated with excellent results. Experience is a key element to overcome the limitations of this technology. Finally, the robotic platform could improve results in difficult MV repair.

Abstract 15582: Robotic-Assisted versus Conventional Mitral Valve Repair: An Updated Meta-Analysis of Operative and Post-Operative Outcomes

Introduction: Cardiac surgery has seen notable advancements, especially in mitral valve repair, with the emergence of robotic-assisted mitral valve repair (RAMVR). Amid ongoing debates about RAMVR's efficacy and safety versus conventional mitral valve repair (CMVR), this updated meta-analysis offers a comprehensive comparison based on recently published data. Aim: The study aims to provide a comparison of RAMVR and CMVR, focusing on key operative and postoperative outcomes. Methods: A systematic search was conducted utilizing databases such as PubMed, EMBASE, and the Cochrane Library, until January 2023. The inclusion criteria included studies that compared RAMVR with CMVR. The meta-analysis incorporated a random-effects model to calculate pooled mean differences (MD) and relative risks (RR). All statistical analyses were carried out using R software (version 4.0.3), by metafor and meta packages. Results: Ten studies with a total of 54,235 patients (5,092 in the RAMVR group and 49,143 in the CMVR group) were included. The meta-analysis showed that RAMVR was associated with a significantly shorter hospital stay (MD -1.79 days; 95% CI -2.77 to -0.83, P=&lt;0.01, I2=100%) and ICU length of stay (MD -16.76 days; 95% CI -29.34 to -4.19, P=&lt;0.01, I2=98%). However, RAMVR was associated with significantly longer cardiopulmonary bypass time (MD 42.90 minutes; 95% CI 29.58 to 56.22, P&lt;0.01, I2=98%) and cross-clamp time (MD 29.67 minutes; 95% CI 19.84 to 39.51, P&lt;0.01, I2=98%). In terms of relative risks, RAMVR had a lower rate of overall mortality (RR 0.55; 95% CI 0.42 to 0.74, P&lt;0.01, I2=0%) and rate of infection (RR 0.62; 95% CI 0.52 to 0.74, P&lt;0.01, I2=0%). However, there was no statistically significant difference in the rate of blood transfusion, stroke rate, atrial fibrillation, and transient ischemic attack. Conclusions: This study suggests that RAMVR may offer benefits such as shorter hospital and ICU stays and lower overall mortality and infection rates, but it also involves longer cardiopulmonary bypass and cross-clamp times. Given the high heterogeneity across the included studies, this underlines the importance of further high-quality randomized controlled trials to optimize RAMVR techniques for improving patient outcomes in mitral valve repair.

Learning Curve Analysis of Robotic-Assisted Mitral Valve Repair with COVID-19 Exogenous Factor: A Single Center Experience.

Background and objective Renewed interest in robot-assisted cardiac procedures has been demonstrated by several studies. However, concerns have been raised about the need for a long and complex learning curve. In addition, the COVID-19 pandemic in 2020 might have affected the learning curve of these procedures. In this study, we investigated the impact of COVID-19 on the learning curve of robotic-assisted mitral valve surgery (RAMVS). The aim was to understand whether or not the benefits of RAMVS are compromised by its learning curve. Materials and Methods Between May 2019 and March 2023, 149 patients underwent RAMVS using the Da Vinci® X Surgical System at the Humanitas Gavazzeni Hospital, Bergamo, Italy. The selection of patients enrolled in the study was not influenced by case complexity. Regression models were used to formalize the learning curves, where preoperative data along with date of surgery and presence of COVID-19 were treated as the input covariates, while intraoperative and postoperative data were analyzed as output variables. Results The age of patients was 59.1 ± 13.3 years, and 70.5% were male. In total, 38.2% of the patients were operated on during the COVID-19 pandemic. The statistical analysis showed the positive impact of the learning curve on the trend of postoperative parameters, progressively reducing times and other key indicators. Focusing on the COVID-19 pandemic, statistical analysis did not recognize an impact on postoperative outcomes, although it became clear that variables not directly related to the intervention, especially ICU hours, were strongly influenced by hospital logistics during COVID-19. Conclusions Understanding the learning curve of robotic surgical procedures is essential to ensure their effectiveness and benefits. The learning curve involves not only surgeons but also other health care providers, and establishing a stable team in the early stage, as in our case, is important to shorten the duration. In fact, an exogenous factor such as the COVID-19 pandemic did not affect the robotic program despite the fact that the pandemic occurred early in the program.

Systematic Review and Meta-Analysis of Mid-Term Survival, Reoperation, and Recurrent Mitral Regurgitation for Robotic-Assisted Mitral Valve Repair

Over the past two decades, surgical approaches for mitral valve (MV) disease have evolved with the advent of minimally invasive techniques. The safety and efficacy of robotic MV repair (RMVr) has been well documented; however, mid- to long-term data are limited. This review aimed to provide a comprehensive analysis of the available mid- to long-term data for RMVr.

Transesophageal echocardiography for cardiac herniation occurring during robotic-assisted mitral valve repair: a case report

BackgroundCardiac herniation has been reported in thoracic trauma and after pneumonectomy; however, it is sporadic in cardiac surgery.Case presentationA 35-year-old male patient underwent an elective totally endoscopic robotic-assisted mitral valve repair (TERMVR). His hemodynamics were stable after weaning from cardiopulmonary bypass, and no residual mitral valve regurgitation was observed. However, during suturing of the port wound, the patient developed hypotension, which improved with phenylephrine administration. Four-chamber transesophageal echocardiography (TEE) images showed cardiac deformity, and postoperative chest radiography confirmed the dextrocardia. The cardiac herniation was repaired by deflating the left lung and over-inflating the right lung using a double-lumen tube, allowing selective ventilation without re-thoracotomy. The patient was discharged on the sixth postoperative day without complications.ConclusionsThis was a very unusual case of cardiac herniation during TERMVR visualized using distinct TEE images. The cardiac herniation was successfully repaired using a double-lumen tube without re-thoracotomy.

Percutaneous retrieval of a migrated suture needle from renal artery

Loop-snare technique is very useful for retrieval of intravascular retained items, such as wires, catheters, coils, and even stents. These items are relatively soft and foldable. Endovascular retrieval of a stiff and sharp item such as suture needle was rarely reported. Here, we report a case of a 42-year-old male that had a missed suture needle during robotic-assisted mitral valve repair. This needle has migrated into the left renal artery. We successfully retrieved the foreign body by aligning both guiding sheath and suture needle in the same concave direction.

Robotic mitral valve repair in National Taiwan University Hospital: 10-year results.

With the help of robotic surgical systems and their 3-dimensional, high-resolution imaging, mitral repair with long shaft instruments and endo-wrist functionality has become a feasible reality. Patients benefit from maintained thoracic cage integrity, reduced surgical trauma, and faster return to normal functional activity. We describe National Taiwan University Hospital's 10-year experience with robotic-assisted mitral valve repair procedures for repairing mitral regurgitation. We performed a retrospective observational cohort study of patients undergoing robotic-assisted mitral valve repair for severe mitral regurgitation at National Taiwan University Hospital. Between January 2012 and September 2022, 450 consecutive patients underwent robotic mitral valve repair with or without additional cardiac procedures. All procedures were completed by a single surgical team. Four hundred and fifty patients, with 272 (60.4%) isolated mitral repairs and 178 (39.6%) combined additional (one or more) cardiac procedures were performed. The Euroscore II estimate mortality was 3.1%±2.7%. The average cardiopulmonary bypass (CPB) time was 124±42 minutes, and the average operation time was 165±51 minutes. Perioperative and 30-day mortality was observed in one (0.22%) patient. Mean intensive care unit stay was 26.5±26.0 hours. Postoperative stroke was observed in one (0.22%) patient and new-onset atrial fibrillation was observed in 71 (15.78%) patients. All patients were in less than mild mitral regurgitation and 422 (93.78%) had none or trace regurgitation at discharge. Freedom from moderate mitral regurgitation was 97.6%, and freedom from mitral valve reoperation was 98% at 10 years. With standardized robotic procedures and non-compromised repair techniques, excellent short-term outcomes and long-term valve repair durability can be achieved in experienced centers.

Systematic review and meta-analysis of mid-term survival, reoperation, and recurrent mitral regurgitation for robotic-assisted mitral valve repair.

Over the past two decades surgical approaches for mitral valve (MV) disease have evolved with the advent of minimally invasive techniques. Robotic mitral valve repair (RMVr) safety and efficacy has been well documented, however, mid- to long-term data are limited. The aim of this review was to provide a comprehensive analysis of the available mid- to long-term data for RMVr. Electronic searches of five databases were performed to identify all relevant studies reporting minimum five-year data on RMVr. Pre-defined primary outcomes of interest were overall survival, freedom from MV reoperation and from moderate or worse mitral regurgitation (MR) at five years or more post-RMVr. A meta-analysis of proportions or means was performed, utilizing a random effects model, to present the data. Kaplan-Meier curves were aggregated using reconstructed individual patient data. Nine studies totaling 3,300 patients undergoing RMVr were identified. Rates of overall survival at 1-, 5- and 10-year were 99.2%, 97.4% and 92.3%, respectively. Freedom from MV reoperation at eight-years post RMVr was 95.0%. Freedom from moderate or worse MR at seven years was 86.0%. Rates of early post-operative complications were low with only 0.2% all-cause mortality and 1.0% cerebrovascular accident. Reoperation for bleeding was low at 2.2% and successful RMVr was 99.8%. Mean intensive care unit and hospital stay were 22.4 hours and 5.2 days, respectively. RMVr is a safe procedure with low rates of early mortality and other complications. It can be performed with low complication rates in high volume, experienced centers. Evaluation of available mid-term data post-RMVr suggests favorable rates of overall survival, freedom from MV reoperation and from moderate or worse MR recurrence.

Two hundred robotic mitral valve repair procedures for degenerative mitral regurgitation: the Yale experience.

BackgroundRobotic surgery has gained popularity over the past two decades due to the benefits related to smaller surgical incisions, enhanced technical dexterity and better intraoperative visualization. We present the Yale experience of the first two hundred totally endoscopic, robotic-assisted mitral valve repair procedures for the treatment of degenerative mitral regurgitation.MethodsWe performed a retrospective cohort study of patients undergoing totally endoscopic, robotic-assisted isolated or concomitant mitral valve repair for degenerative mitral regurgitation at Yale-New Haven Hospital from October 2018 to April 2022. Mitral valve repair procedures for rheumatic or secondary functional mitral regurgitation and planned robotic-assisted mitral valve replacement cases were excluded.ResultsTwo hundred consecutive procedures were performed. The median age was 65 years (interquartile range, 58–73 years). Six patients (3.0%) had a history of mediastinal radiation, four patients (2.0%) had previous cardiac surgery, and one patient (0.5%) had cardiac dextroversion. Median cardiopulmonary bypass and aortic cross-clamp times were 122 and 79 minutes, respectively. Femoral vessel cannulation was performed percutaneously in 57 (28.5%) patients with no major access-site related complication. Aortic cross-clamping was performed with the endoaortic balloon occlusion device in 151 (75.5%) patients. No conversions to sternotomy occurred. Satisfactory repair was achieved in 100% of cases, with 184 (92.0%) and 16 (8.0%) of patients having trace/none or mild residual mitral regurgitation, respectively. Forty-two patients (21.0%) underwent concomitant Cox-maze procedure and 25 patients (12.5%) underwent concomitant tricuspid valve repair. Thirty-day mortality rate was 0.5%, with an observed-to-expected ratio of 0.53. Two patients (1.0%) underwent re-exploration for bleeding, one had early postoperative stroke (0.5%), five developed pneumothorax (2.5%) and two required dialysis for acute renal failure (1.0%). The median length of hospital stay was four days.ConclusionsExcellent short-term outcomes can be achieved in experienced centers for the treatment of degenerative mitral regurgitation with a totally endoscopic, robotic-assisted approach.

Evaluation of robotic-assisted mitral surgery in a contemporary experience.

To evaluate the safety/effectiveness of a recently established robotic-assisted mitral surgery program. Cohort study with prospective collection of clinical data of 59 consecutive recipients (May 2019-August 2021) of robotic-assisted (fourth-generation platform, DaVinci X) mitral valve repair for degenerative disease, using a totally endoscopic technique. Patients' selection was based on defined anatomical and clinical criteria. We established a dedicated multidisciplinary protocol to facilitate postoperative fast-tracking, and a systematic in-house clinical and echocardiographic follow-up at 3, 6, and 12 postoperative months. All patients (89.8% men, average age 58 ± 12 years) received mitral valve repair; there was no operative mortality, one conversion to sternotomy (1.7%) and one stroke (1.7%). Extubation within the operative theater occurred in 28.8%; average mechanical ventilation time and ICU stay was 2.8 ± 4.1 and 32.5 ± 15.8 h (after exclusion of one outlier, learning-curve period, suffering from perioperative stroke); average postoperative hospital stay was 6.8 ± 3.4 days and 96.6% of patients were discharged home. One patient was transfused (1.7%); there were no other complications. Follow-up revealed stability of the results of mitral repair, with one (1.7%) persistent (>2+/4+) mitral regurgitation, and stability of coaptation height over time. We observed optimal functional results (class I was 98% at 3 months and 96% at 12 months). Quarterly case load consistently increased during the experience. This initial experience suggests the reliability and clinical safety of a recently established local robotic-assisted mitral surgery. This strategy can facilitate faster postoperative recovery, and its positioning in the therapeutic armamentarium needs to be defined.

An analysis of thelearning curve for robotic-assisted mitral valve repair.

Many cardiac surgeons receive training for sternotomy-based cardiac surgical operations in residency programs and only a few education programs offer training specifically in minimally invasive cardiac surgery. In this report, we aimed to search and analyze the learning curve for robotic-assisted mitral valve (MV) repair in cardiac surgeons. Between January 2010 and July 2019, 60 robotic-assisted isolated MV repair surgeries were performed with DaVinci Robotic Systems in our center. Different kinds of surgical techniques were used. The assessment of the learning curve was based on cardiopulmonary bypass (CPB) and transthoracic aortic clamp (CC) times. There were 23 (38.3%) men and 37 (61.7%) women with a mean age of 48.3 years. The lesions of the MV were posterior leaflet prolapsus (n = 42, 70.0%), anterior leaflet prolapsus (n = 8, 13.3%), Barlow disease (n = 3, 5%), and annular dilatation (n = 7, 11.6%). The patients underwent notochordal implantation (n = 27, 45%), quadrangular or triangular resection (n = 23, 38.3%), isolated ring annuloplasty (n = 7, 11.7%), resection, and leaflet reduction (n = 2, 3.3%) or edge to edge repair (n = 1, 1.7%). The maturation of the learning curve appeared to be about 30 cases. The statistical analysis showed that the mean CPB and CC times for the first 30 cases were greater compared with the 30 after learning curve (155.3 vs. 118.9 min[p = .00], 102.3 vs. 80 min[p = .00], respectively). There was no case of conversion to open surgery. No perioperative mortality was observed. The maturation of the learning curve for robotic-assisted MV repair appeared to be about 30 cases in our group of patients. This study had encouraging results for surgeons who desire to start a robotic mitral surgery program.

Postoperative Nausea and Vomiting and Pain After Robotic-Assisted Mitral Valve Repair

To determine the rate and clinical factors associated with postoperative nausea and vomiting (PONV) and severe pain after robotic-assisted mitral valve repair. Retrospective chart review. Major quaternary academic medical center. Adult patients undergoing robotic-assisted mitral valve repair from May 5, 2018 through September 13, 2019. Participant electronic medical records were abstracted for clinical characteristics, PONV within the first 72 postoperative hours, episodes of severe pain (defined as pain score ≥7 using an 11-point numerical pain rating scale), and opioid use within the first 24 postoperative hours. Multivariate analyses were performed. Of 124 participants, PONV was noted in 83 (67%; 95% confidence interval [CI] 58%-75%) patients and severe pain in 96 (77%, 95% CI 69%-84%) patients. The median (interquartile range) time to PONV was 6.1 (3.7-14.7) hours. After adjusting for age, sex, and duration of surgery, pre-incisional use of methadone was associated with reduced risk for severe pain (odds ratio 0.40 [95% CI 0.16-0.99]; p = 0.048) and a lower 24-postoperative hour opioid requirement (estimate -29.0 mg intravenous morphine equivalents [95% CI -46.7 to -11.3]; p = 0.006). However, methadone was not associated with a reduction of the cumulative opioid dose (intraoperative and 24-hour postoperative opioid dose; p = 0.248). Both severe pain and PONV were associated with longer hospital stay. PONV and severe pain are common after robotic-assisted mitral valve repair. Peri-incisional methadone is associated with a modest decrease in the severe pain rate but without a reduction in opioid dose or hospital stay.

Changes in Right Ventricle Function After Mitral Valve Repair Surgery

Right ventricular (RV) dysfunction can occur after cardiac surgery and persist for years. We assessed perioperative RV systolic function in patients undergoing mitral valve (MV) repair and further compared minimally invasive robotic-assisted mitral valve repair (MIMVr) vs standard 'open' MV repair (MVr). Speckle tracking (RV free wall strain [RVS]) was used as a sensitive echocardiography method to assess RV function. Retrospective analysis, over 3 years, of consecutive patients (n = 158) referred to Mayo Clinic (Rochester, MN, USA). Preoperative, pre-discharge and 1 year transthoracic echocardiograms were reviewed. A prospective pilot study was performed for sample size estimation. Primary outcome was RV free wall strain (RVS). Right ventricular free wall strain declined after MV repair surgery (-22.6 ± 7% vs -15 ± 6%, p < 0.001). There were smaller reductions in RVS in MIMVr vs MVr group (-6.0 ± 9% vs -10.3 ± 8%, p < 0.01), which persisted after adjusting for baseline values (RVS treatment effect 1.5%, p = 0.007). There was greater recovery in MIMVr vs MVr group at 1 year follow-up vs pre-surgery values (-3.4 ± 9% vs -8.1 ± 8% respectively, p < 0.001, RVS treatment effect 1.7%, p = 0.001). Bypass time was higher in the MIMVr group (80min ± 22 vs 40min ± 20, p < 0.0001). The echo findings remained significant correcting for age, pulmonary pressures and change in ejection fraction. Right ventricular systolic dysfunction is common after MV repair surgery. Deterioration in RV contraction is less pronounced following MIMVr vs MVr and is associated with enhanced RV functional recovery at 1 year, albeit not to preoperative levels. This may potentially be associated with clinical functional improvement but further studies are warranted to investigate this.

A Population-Based Analysis of Robotic-Assisted Mitral Valve Repair

Robotic-assisted mitral valve repair is becoming more frequently performed in cardiac surgery. However, little is known about its utilization and safety at a national level. Patients undergoing mitral valve repair in the United States from 2008 to 2012 were identified in the National Inpatient Sample. Inhospital mortality, complications, length of stay, and cost for patients undergoing robotic-assisted mitral valve repair were compared with patients undergoing nonrobotic procedures. We identified 50,408 isolated mitral valve repair surgeries, of which 3,145 were done with robotic assistance. In a propensity score matched analysis of 631 pairs of patients, we found no difference between patients undergoing robotic-assisted and nonrobotic-assisted mitral valve repair with respect to inhospital mortality, complications, or composite outcomes in unadjusted or multivariable analyses. Robotic-assisted mitral valve repair surgery was associated with a shorter median length of stay (4 versus 6 days, p < 0.001), and there was no difference in median total costs between the two procedures. In our analysis of a large national database with its inherent limitations, robotic-assisted mitral valve repair was found to be safe, with an acceptable morbidity and mortality profile.

Robotic-assisted mitral valve repair: surgical technique.

Robotic-assisted mitral valve repair represents the least invasive surgical approach currently available for anatomical mitral valve repair in patients with myxomatous mitral valve disease. Standard mitral valve repair techniques utilized during conventional sternotomy/right thoracotomy are exactly replicated with the robotic instrumentation through 1-2 cm port-like incisions with superior 3D visualization. This is performed on cardiopulmonary bypass by peripheral cannulation of the femoral vessels/right internal jugular vein. The ascending aorta is occluded with a transthoracic aortic cross-clamp. Antegrade cardioplegia is delivered centrally into the aortic root through a cardioplegia vent catheter. By replicating conventional mitral valve repair done via an open sternotomy approach, the quality of mitral valve repair is ensured while providing the patients with advantages of less invasive surgery including shorter hospital stay, rapid recovery and return to normal activities, less blood transfusion, superior cosmesis and complete elimination of sternotomy-related morbidities such as deep sternal wound infection and sternal dehiscence. We reviewed the first consecutive 200 patients undergoing robotic mitral valve repair at Mayo Clinic Rochester between 24 January 2008 and 28 January 2011. Successful mitral valve repair was completed in all patients. There were no early (30-day) deaths. One patient suffered a stroke (0.5%). One patient required reoperation for bleeding (0.5%). Two patients (1%) required reoperation for recurrent mitral regurgitation. Twelve patients (6%) required transfusion of allogeneic blood products. We have noted a significant reduction in operative times and resource utilization over time.

Robotic assisted mitral valve repair: early experience with the da Vinci S robotic system

Robotic assisted mitral valve repair: early experience with the da Vinci S robotic system

Lung Hernia Following Robotic-Assisted Mitral Valve Repair

Lung hernia is an uncommon diagnosis characterized by lung tissue protruding through a chest wall defect. It may occur spontaneously, as a congenital defect, as a result of trauma, or as a postsurgical complication. We describe the occurrence of lung hernia and subsequent successful herniorraphy in two patients following robotic-assisted mitral valve repair.

Viscoelastic Modeling of the Contact Interaction Between a Tactile Sensor and an Atrial Tissue

Modeling and parameter identification of soft tissue are essential in establishing an accurate contact model for tool-tissue interaction, which can be used in the development of high-fidelity surgical instruments. This paper discusses the interaction between a tissue and a tactile sensor in minimally invasive surgery, the focus being a novel technique for robotic-assisted mitral valve repair, in which tactile sensors are used to distinguish between different kinds of tissue by their relative softness. A discrete viscoelastic model is selected to represent the tissue behavior. To populate the model of the tissue with actual data, a set of tissue-testing experiments is designed and implemented on the atrial tissue of a swine heart by analyzing its dynamic response. By means of a genetic algorithm, data of the complex compliance are extracted and used to find the coefficients of the model. Further, a viscoelastic contact model is developed to model the interaction between the tissue and the tactile sensor with annular shape. Finally, the relation among the indentation displacement, the ratio of the radii, and the applied force is established parametrically.

Simultaneous Robotic-Assisted Mitral Valve Repair and Percutaneous Coronary Intervention

We present a case report of a robotic-assisted mitral valve repair with simultaneous percutaneous coronary intervention. A 58-year-old man presented with New York Heart Association class III symptoms from severe mitral regurgitation and significant stenosis of the right coronary artery. In a hybrid operating theater, the patient underwent placement of a bare metal stent in the right coronary artery followed immediately by robotic-assisted mitral valve repair. Both procedures were successful and occurred in a timely fashion. The patient experienced no immediate postoperative complications and was discharged home on postoperative day 5. At 2-week follow-up, he had returned to his normal activities of daily living and at 1 year remained asymptomatic. This case report demonstrates the benefits of minimally invasive robotic mitral valve repair in allowing for successful repair, early postoperative return to activity, minimal incision pain, and high patient satisfaction. It further highlights the potential benefit of a hybrid operating theater in allowing surgical and percutaneous coronary intervention procedures to be delivered in a safe and efficient manner.