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Importance: Assessing nontechnical skills in operating rooms (ORs) is crucial for enhancing surgical performance and patient safety. However, automated and real-time evaluation of these skills remains challenging., Objective: To explore the feasibility of using motion features extracted from surgical video recordings to automatically assess nontechnical skills during cardiac surgical procedures., Design, Setting, and Participants: This cross-sectional study used video recordings of cardiac surgical procedures at a tertiary academic US hospital collected from January 2021 through May 2022. The OpenPose library was used to analyze videos to extract body pose estimations of team members and compute various team motion features. The Non-Technical Skills for Surgeons (NOTSS) assessment tool was employed for rating the OR team's nontechnical skills by 3 expert raters., Main Outcomes and Measures: NOTSS overall score, with motion features extracted from surgical videos as measures., Results: A total of 30 complete cardiac surgery procedures were included: 26 (86.6%) were on-pump coronary artery bypass graft procedures and 4 (13.4%) were aortic valve replacement or repair procedures. All patients were male, and the mean (SD) age was 72 (6.3) years. All surgical teams were composed of 4 key roles (attending surgeon, attending anesthesiologist, primary perfusionist, and scrub nurse) with additional supporting roles. NOTSS scores correlated significantly with trajectory (r = 0.51, P = .005), acceleration (r = 0.48, P = .008), and entropy (r = -0.52, P = .004) of team displacement. Multiple linear regression, adjusted for patient factors, showed average team trajectory (adjusted R2 = 0.335; coefficient, 10.51 [95% CI, 8.81-12.21]; P = .004) and team displacement entropy (adjusted R2 = 0.304; coefficient, -12.64 [95% CI, -20.54 to -4.74]; P = .003) were associated with NOTSS scores., Conclusions and Relevance: This study suggests a significant link between OR team movements and nontechnical skills ratings by NOTSS during cardiac surgical procedures, suggesting automated surgical video analysis could enhance nontechnical skills assessment. Further investigation across different hospitals and specialties is necessary to validate these findings.

Clinical alarm and decision support systems that lack clinical context may create non-actionable nuisance alarms that are not clinically relevant and can cause distractions during the most difficult moments of a surgery. We present a novel, interoperable, real-time system for adding contextual awareness to clinical systems by monitoring the heart-rate variability (HRV) of clinical team members. We designed an architecture for real-time capture, analysis, and presentation of HRV data from multiple clinicians and implemented this architecture as an application and device interfaces on the open-source OpenICE interoperability platform. In this work, we extend OpenICE with new capabilities to support the needs of the context-aware OR including a modularized data pipeline for simultaneously processing real-time electrocardiographic (ECG) waveforms from multiple clinicians to create estimates of their individual cognitive load. The system is built with standardized interfaces that allow for free interchange of software and hardware components including sensor devices, ECG filtering and beat detection algorithms, HRV metric calculations, and individual and team alerts based on changes in metrics. By integrating contextual cues and team member state into a unified process model, we believe future clinical applications will be able to emulate some of these behaviors to provide context-aware information to improve the safety and quality of surgical interventions.

Importance: Value-based purchasing creates pressure to examine whether newer technologies and care processes, including new surgical techniques, yield any economic advantage., Objective: To compare health care costs and utilization between participants randomized to receive endoscopic vein harvesting (EVH) or open vein harvesting (OVH) during a coronary artery bypass grafting (CABG) procedure., Design, Setting, and Participants: This secondary economic analysis was conducted alongside the 16-site Randomized Endo-Vein Graft Prospective (REGROUP) clinical trial funded by the Department of Veterans Affairs (VA) Cooperative Studies Program. Adults scheduled for urgent or elective bypass involving a vein graft were eligible. The first participant was enrolled in September 2013, with most sites completing enrollment by March 2014. The last participant was enrolled in April 2017. A total of 1150 participants were randomized, with 574 participants receiving OVH and 576 receiving EVH. For this secondary analysis, cost and utilization data were extracted through September 30, 2020. Participants were linked to administrative data in the VA Corporate Data Warehouse and activity-based cost data starting with the index procedure., Interventions: EVH vs OVH, with comparisons based on intention to treat., Main Outcomes and Measures: Discharge costs for the index procedure as well as follow-up costs (including intended and unintended events; mean [SD] follow-up time, 33.0 [19.9] months) were analyzed, with results from different statistical models compared to test for robustness (ie, lack of variation across models). All costs represented care provided or paid by the VA, standardized to 2020 US dollars., Results: Among 1150 participants, the mean (SD) age was 66.4 (6.9) years; most participants (1144 [99.5%] were male. With regard to race and ethnicity, 6 participants (0.5%) self-reported as American Indian or Alaska Native, 10 (0.9%) as Asian or Pacific Islander, 91 (7.9%) as Black, 62 (5.4%) as Hispanic, 974 (84.7%) as non-Hispanic White, and 6 (0.5%) as other race and/or ethnicity; data were missing for 1 participant (0.1%). The unadjusted mean (SD) costs for the index CABG procedure were $76 607 ($43 883) among patients who received EVH and $75 368 ($45 900) among those who received OVH, including facility costs, insurance costs, and physician-related costs (commonly referred to as provider costs in Centers for Medicare and Medicaid and insurance data). No significant differences were found in follow-up costs; per 90-day follow-up period, EVH was associated with a mean (SE) added cost of $302 ($225) per patient. The results were highly robust to the statistical model., Conclusions and Relevance: In this study, EVH was not associated with a reduction in costs for the index CABG procedure or follow-up care. Therefore, the choice to provide EVH may be based on surgeon and patient preferences., Trial Registration: ClinicalTrials.gov Identifier: NCT01850082.

Objective: This novel preliminary study sought to capture dynamic changes in heart rate variability (HRV) as a proxy for cognitive workload among perfusionists while operating the cardiopulmonary bypass (CPB) pump during real-life cardiac surgery., Background: Estimations of operators' cognitive workload states in naturalistic settings have been derived using noninvasive psychophysiological measures. Effective CPB pump operation by perfusionists is critical in maintaining the patient's homeostasis during open-heart surgery. Investigation into dynamic cognitive workload fluctuations, and their relationship with performance, is lacking in the literature., Method: HRV and self-reported cognitive workload were collected from three Board-certified cardiac perfusionists ( N = 23 cases). Five HRV components were analyzed in consecutive nonoverlapping 1-min windows from skin incision through sternal closure. Cases were annotated according to predetermined phases: prebypass, three phases during bypass, and postbypass. Values from all 1min time windows within each phase were averaged., Results: Cognitive workload was at its highest during the time between initiating bypass and clamping the aorta (preclamp phase during bypass), and decreased over the course of the bypass period., Conclusion: We identified dynamic, temporal fluctuations in HRV among perfusionists during cardiac surgery corresponding to subjective reports of cognitive workload. Not only does cognitive workload differ for perfusionists during bypass compared with pre- and postbypass phases, but differences in HRV were also detected within the three bypass phases., Application: These preliminary findings suggest the preclamp phase of CPB pump interaction corresponds to higher cognitive workload, which may point to an area warranting further exploration using passive measurement.

Importance: Randomized clinical trials (RCTs) provide the highest level of evidence to evaluate 2 or more surgical interventions. Surgical RCTs, however, face unique challenges in design and implementation., Objective: To evaluate the design, conduct, and reporting of contemporary surgical RCTs., Evidence Review: A literature search performed in the 2 journals with the highest impact factor in general medicine as well as 6 key surgical specialties was conducted to identify RCTs published between 2008 and 2020. All RCTs describing a surgical intervention in both experimental and control arms were included. The quality of included data was assessed by establishing an a priori protocol containing all the details to extract. Trial characteristics, fragility index, risk of bias (Cochrane Risk of Bias 2 Tool), pragmatism (Pragmatic Explanatory Continuum Indicator Summary 2 [PRECIS-2]), and reporting bias were assessed., Findings: A total of 388 trials were identified. Of them, 242 (62.4%) were registered; discrepancies with the published protocol were identified in 81 (33.5%). Most trials used superiority design (329 [84.8%]), and intention-to-treat as primary analysis (221 [56.9%]) and were designed to detect a large treatment effect (50.0%; interquartile range [IQR], 24.7%-63.3%). Only 123 trials (31.7%) used major clinical events as the primary outcome. Most trials (303 [78.1%]) did not control for surgeon experience; only 17 trials (4.4%) assessed the quality of the intervention. The median sample size was 122 patients (IQR, 70-245 patients). The median follow-up was 24 months (IQR, 12.0-32.0 months). Most trials (211 [54.4%]) had some concern of bias and 91 (23.5%) had high risk of bias. The mean (SD) PRECIS-2 score was 3.52 (0.65) and increased significantly over the study period. Most trials (212 [54.6%]) reported a neutral result; reporting bias was identified in 109 of 211 (51.7%). The median fragility index was 3.0 (IQR, 1.0-6.0). Multiplicity was detected in 175 trials (45.1%), and only 35 (20.0%) adjusted for multiple comparisons., Conclusions and Relevance: In this systematic review, the size of contemporary surgical trials was small and the focus was on minor clinical events. Trial registration remained suboptimal and discrepancies with the published protocol and reporting bias were frequent. Few trials controlled for surgeon experience or assessed the quality of the intervention.

Compared with randomized controlled trials (RCTs) in medical specialties, RCTs in cardiac surgery face specific issues. Individual and collective equipoise, rapid evolution of the surgical techniques, as well as difficulties in obtaining funding, and limited education in clinical epidemiology in the surgical community are among the most important challenges in the design phase of the trial. Use of complex interventions and learning curve effect, differences in individual operators' expertise, difficulties in blinding, and slow recruitment make the successful completion of cardiac surgery RCTs particularly challenging. In fact, over the course of the last 20 years, the number of cardiac surgery RCTs has declined significantly. In this review, a team of surgeons, trialists, and epidemiologists discusses the most important challenges faced by RCTs in cardiac surgery and provides a list of suggestions for the successful design and completion of cardiac surgery RCTs., (Copyright © 2020 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.)

Introduction: The complexities and risks inherent to the field of surgery and surgical interventions present unique challenges to the design and analysis of surgical randomized controlled trials (RCT). Prior studies have investigated the practical and methodologic challenges posed by surgical RCTs. To date, however, a comprehensive analysis of the contemporary literature across multiple surgical subspecialties does not exist. In this descriptive analysis, we set out to characterize surgical RCTs over the past 10 years across six major surgical specialties., Methods and Analysis: A literature search by a medical librarian will be performed to identify all surgical randomized clinical trials published between January 2009 and December 2019 in the two journals with the highest impact factor for six surgical specialties as well as two large general medicine journals. Two reviewers will independently screen the citations retrieved from the literature search and extract data according to a previously described protocol via a pre-defined data collection form. Categorical variables will be reported as counts and percentages. Following assessment of normality, continuous variables will be reported as mean (standard deviation) or median (inter-quartile range). Based on normality of data, independent t-test or the Mann-Whitney U test will be used to compare continuous variables and chi-square and Fisher's exact tests to compare categorical variables. Comparisons across multiple sets will be performed using ANOVA or Kruskak-Wallis tests. Two-sided significance testing will be used and a p-value <0.05 will be considered significant without adjustment for multiple testing. All analyses will be performed using SPSS version 24 and R within RStudio. PROSPERO (ID number: 162797)., Ethics and Dissemination: There are no ethical concerns directly pertinent to this systematic review. The retrieved data will be made available upon request. The study will be written in English and submitted for publication in a peer-reviewed journal., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2020 The Authors.)

Traditionally, blood flow rates on cardiopulmonary bypass are based primarily on a formula that matches cardiac index to the patient's body surface area (BSA). However, Ranucci and associates in the Goal-Directed Perfusion Trial (GIFT) trial have shown that coupling the BSA with delivery of oxygen (DO 2 ), known as goal-directed perfusion (GDP), may be a safer approach to determine appropriate blood flows. The objective of this study was to create a GDP reference tool that would allow perfusionists to quickly determine the lowest acceptable blood flow needed to provide a patient of any BSA with a satisfactory DO 2 without the need for additional dedicated technology. We approached this problem by deriving a formula for flow (L/min), based on BSA, oxygen content of the blood, and a minimum DO 2 of 280 mL·min -1 m -2 . A quick reference GDP chart was created based on the derived formula, requiring only the patient's BSA and hemoglobin level to determine a safe minimum flow rate. The proposed tool allows any cardiac surgery center to adopt the GDP technique, even in the absence of instantaneous DO 2 monitoring equipment.

The operating room (OR) is a high-risk and complex environment, where multiple specialized professionals work as a team to effectively care for patients in need of surgical interventions. Surgical tasks impose high cognitive demands on OR staff and cognitive overload may have deleterious effects on team performance and patient safety. The aim of the present study was to investigate the feasibility and describe a novel methodological approach to characterize dynamic changes in team cognitive load by measuring synchronization and entropy of heart rate variability parameters during real-life cardiac surgery. Cognitive load was measured by capturing interbeat intervals (IBI) from three team members (surgeon, anesthesiologist and perfusionist) using an unobtrusive wearable heart rate sensor and transmitted in real-time to a smartphone application. Clinical data and operating room audio/video recordings were also collected to provide behavioral and contextual information. We developed symbolic representations of the transient cognitive state of individual team members (Individual Cognitive State - ICS), and overall team (Team Cognitive State - TCS) by comparing IBI data from each team member with themselves and with others. The distribution of TCS symbols during surgery enabled us to display and analyze temporal states and dynamic changes of team cognitive load. Shannon's entropy was calculated to estimate the changing levels of team organization and to detect fluctuations resulting from a variety of cognitive demands and/or specific situations (e.g. medical error, emergency, flow disruptions). An illustrative example from a real cardiac surgery team shows how cognitive load patterns shifted rapidly after an actual near-miss medication event, leading the team to a more organized and synchronized state. The methodological approach described in this study provides a measurement technique for the assessment of team physiological synchronization, which can be applied to many other team-based environments. Future research should gather additional validity evidence to support the proposed methods for team cognitive load measurement., (Copyright © 2019 Elsevier Inc. All rights reserved.)

If a perfusionist weans a patient off the heart lung machine (HLM) and the anesthesiologist has not re-started the ventilator, the patient will become hypoxic. The objective of this project was to create a redundant safety system of verbal and electronic communication to prevent failure to ventilate errors after cardiopulmonary bypass. This objective could be realized by building an electronic communication bridge directly between the HLM and ventilator. A software application was created to retrieve and interpret data from the pump and ventilator and trigger a programmed smart alarm. The software is able to interpret data from the pump and ventilator. When both are off simultaneously (defined as a pump flow of 0 L/min with a respiratory rate of 0 breaths/min), the application will raies an alarm. Communication between a pump and ventilator is possible, enabling the deployment of a safety system that could exist in the operating room (OR) as a standalone alarm. A device dataset can be used to optimize clinical performance of the alarm. The application could also be integrated into smart checklists and computer-assisted OR process models that are currently in development.

Surgical team processes are known to be complex and error prone. This paper describes an approach that uses a detailed, validated model of a medical process to provide the clinicians who carry out that complex process with offline and online guidance to help reduce errors. Offline guidance is in the form of a hypertext document describing all the ways the process can be carried out. Online guidance is in the form of a context-sensitive and continually updated electronic "checklist" that lists next steps and needed resources, as well as completed steps. In earlier work, we focused on providing such guidance for single-clinician or single-team processes. This paper describes guiding the collaboration of multiple teams of clinicians through complex processes with significant concurrency, complicated exception handling, and precise and timely communication. We illustrate this approach by applying it to a highly complex, high risk subprocess of cardiac surgery.

Objective: To compare mitral valve repair (MVRepair) and mitral valve replacement (MVReplace) trends in the Veterans Affairs (VA) Surgical Quality Improvement Program., Methods: Trends were compared by bivariate analyses, followed by backward stepwise selection and multivariable logistic modeling to determine the effect of preoperative comorbidities and facility-level factors on MVRepair (vs MVReplace) rate. A subgroup analysis focused on patients who underwent elective surgery for isolated primary degenerative mitral regurgitation. Propensity matching was done in the overall and primary degenerative cohorts., Results: From October 2000 to October 2013, 4165 veterans underwent MVRepair (n = 2408) or MVReplace (n = 1757) for MV disease of any cause at 40 VA medical centers (procedural volume, 0-29/y; median 7/y). The MVRepair percentage increased from 48% in 2001 to 63% in 2013 (P < .001). MVRepair rates varied widely among centers; center volume explained only 19% of this variation after adjustment for case mix (R 2  = 0.19, P = .005). Unadjusted 30-day and 1-year mortality rates were lower after MVRepair than after MVReplace (3.5% vs 4.8%, P = .04; 9.8% vs 12.1%, P = .02). Among the propensity-matched patients (n = 2520), 30-day and 1-year mortality were similar after MVRepair and MVReplace. In the propensity-matched primary degenerative subgroup (n = 664), unadjusted long-term mortality for up to 10 years postoperatively was lower after MVRepair (28% vs 37%, P = .003), as was risk-adjusted long-term mortality (hazard ratio, 0.78; 95% confidence interval, 0.61-1.01)., Conclusions: In the VA Health System, mortality after MV operations is low. Despite the survival advantage associated with MV repair in primary mitral regurgitation, repair is infrequent at some centers, representing an opportunity for quality improvement., (Copyright © 2017 The American Association for Thoracic Surgery. All rights reserved.)

Background: In preclinical testing, ventricular wall injection of hydrogels has been shown to be effective in modulating ventricular remodeling and preserving cardiac function. For some approaches, early-stage clinical trials are under way. The hydrogel delivery method varies, with minimally invasive approaches being preferred. Endocardial injections carry a risk of hydrogel regurgitation into the circulation, and precise injection patterning is a challenge. An epicardial approach with a thermally gelling hydrogel through the subxiphoid pathway overcomes these disadvantages., Methods: A relatively stiff, thermally responsive, injectable hydrogel based on N-isopropylacrylamide and N-vinylpyrrolidone (VP gel) was synthesized and characterized. VP gel thermal behavior was tuned to couple with a transepicardial injection robot, incorporating a cooling feature to achieve injectability. Ventricular wall injections of the optimized VP gel have been performed ex vivo and on beating porcine hearts., Results: Thermal transition temperature, viscosity, and gelling time for the VP gel were manipulated by altering N-vinylpyrrolidone content. The target parameters for cooling in the robotic system were chosen by thermal modeling to support smooth, repeated injections on an ex vivo heart. Injections at predefined locations and depth were confirmed in an infarcted porcine model., Conclusions: A coupled thermoresponsive hydrogel and robotic injection system incorporating a temperature-controlled injectate line was capable of targeted injections and amenable to use with a subxiphoid transepicardial approach for hydrogel injection after myocardial infarction. The confirmation of precise location and depth injections would facilitate a patient-specific planning strategy to optimize injection patterning to maximize the mechanical benefits of hydrogel placement., (Copyright © 2016 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)

The Randomized Endo-vein Graft Prospective (REGROUP) trial (ClinicalTrials.gov NCT01850082) is a randomized, intent-to-treat, 2-arm, parallel-design, multicenter study funded by the Cooperative Studies Program (CSP No. 588) of the US Department of Veterans Affairs. Cardiac surgeons at 16 Veterans Affairs (VA) medical centers with technical expertise in performing both endoscopic vein harvesting (EVH) and open vein harvesting (OVH) were recruited as the REGROUP surgeon participants. Subjects requiring elective or urgent coronary artery bypass grafting using cardiopulmonary bypass with use of ≥1 saphenous vein graft will be screened for enrollment using pre-established inclusion/exclusion criteria. Enrolled subjects (planned N = 1150) will be randomized to 1 of the 2 arms (EVH or OVH) after an experienced vein harvester has been assigned. The primary outcomes measure is the rate of major adverse cardiac events (MACE), including death, myocardial infarction, or revascularization. Subject assessments will be performed at multiple times, including at baseline, intraoperatively, postoperatively, and at discharge (or 30 days after surgery, if still hospitalized). Assessment of leg-wound complications will be completed at 6 weeks after surgery. Telephone follow-ups will occur at 3-month intervals after surgery until the participating sites are decommissioned after the trial's completion (approximately 4.5 years after the full study startup). To assess long-term outcomes, centralized follow-up of MACE for 2 additional years will be centrally performed using VA and non-VA clinical and administrative databases. The primary MACE outcome will be compared between the 2 arms, EVH and OVH, at the end of the trial duration., (Published 2014. This article is a U.S. Government work and is in the public domain in the USA.)

Objective: The study objective was to determine the predictors of postoperative atrial fibrillation (POAF) in patients randomized to conventional coronary artery bypass graft (on-pump coronary artery bypass [ONCAB]) versus beating heart coronary surgery (off-pump coronary artery bypass [OPCAB])., Methods: The subgroup of 2103 patients (of 2203 enrollees) in the Randomized On Versus Off Bypass trial with no POAF was studied (1056 patients in the ONCAB group and 1047 patients in the OPCAB group). Univariate and multivariate analyses were used to identify the predictors of POAF and the impact of POAF on outcomes., Results: Use of ONCAB versus OPCAB was not associated with increased rates of POAF. Older age (P < .0001), white race (P < .001), and hypertension (P < .002) were predictors of POAF on multivariate analysis. In general, POAF led to a higher rates of reintubation (ONCAB: 6.3% vs 0.8% no POAF, P < .001; OPCAB: 7.4% vs 1.8% no POAF, P < .0001) and prolonged ventilatory support (ONCAB: 7.1% vs 2.3% no POAF, P = .001; OPCAB: 9.2% vs 3.4% no POAF, P = .0003). The rate of any early adverse outcome was higher in patients with POAF (all patients: 10% POAF vs 4.7% no POAF, P < .0001; ONCAB: 9% POAF vs 4.3% no POAF, P = .008; OPCAB: 11% POAF vs 5.1% no POAF, P = .001). The 1-year all cause mortality was higher with POAF for both groups (ONCAB: 5.4% POAF vs 2% no POAF, P = .009; OPCAB: 5.1% POAF vs 2.6% no POAF, P = .07). POAF was independently associated with early composite end point (odds ratio [OR], 2.23; confidence interval [CI], 1.55-3.22; P < .0001), need for new mechanical support (OR, 3.25; CI, 1.39-7.61; P = .007), prolonged ventilatory support (OR, 2.93; CI, 1.89-4.55; P < .0001), renal failure (OR, 5.42; CI, 1.94-15.15; P = .001), and mortality at 12 months (OR, 1.94; CI, 1.14-3.28; P = .01)., Conclusions: In the Randomized On Versus Off Bypass trial, the strategy of revascularization did not affect the rate of POAF. Age, race, and hypertension were predictors of POAF. POAF was independently associated with a higher short-term morbidity and higher 1-year mortality rates., (Published by Mosby, Inc.)

Objective: In the Randomized On/Off Bypass (ROOBY) Trial, the efficacy of on-pump versus off-pump coronary artery bypass grafting was evaluated. This ROOBY Trial planned subanalysis compared the effects on postbypass patient clinical outcomes and graft patency of endoscopic vein harvesting and open vein harvesting., Methods: From April 2003 to April 2007, the technique used for saphenous vein graft harvesting was recorded in 1471 cases. Of these, 894 patients (341 endoscopic harvest and 553 open harvest) also underwent coronary angiography 1 year after coronary artery bypass grafting. Univariate and multivariable analyses were used to compare patient outcomes in the endoscopic and open groups., Results: Preoperative patient characteristics were statistically similar between the endoscopic and open groups. Endoscopic vein harvest was used in 38% of the cases. There were no significant differences in both short-term and 1-year composite outcomes between the endoscopic and open groups. For patients with 1-year catheterization follow-up (n=894), the saphenous vein graft patency rate for the endoscopic group was lower than that in the open harvest group (74.5% vs 85.2%, P<.0001), and the repeat revascularization rate was significantly higher (6.7% vs 3.4%, P<.05). Multivariable regression documented no interaction effect between endoscopic approach and off-pump treatment., Conclusions: In the ROOBY Trial, endoscopic vein harvest was associated with lower 1-year saphenous vein graft patency and higher 1-year revascularization rates, independent of the use of off-pump or on-pump cardiac surgical approach., (Published by Mosby, Inc.)

Objective: Functional ischemic mitral regurgitation is a complication of ventricular remodeling; standard therapy is reduction annuloplasty and coronary artery bypass grafting. Unfortunately, outcomes are retrospective and contradictory. We report a multicenter study that documents the outcomes of reduction annuloplasty for functional ischemic mitral regurgitation., Methods: Twenty-one centers randomized 75 patients to the coronary artery bypass grafting + reduction annuloplasty subgroup that was the control arm of the Randomized Evaluation of a Surgical Treatment for Off-pump Repair of the Mitral Valve trial. Entry criteria included patients requiring revascularization, patients with severe or symptomatic moderate functional ischemic mitral regurgitation, an ejection fraction 25% or greater, a left ventricular end-diastolic dimension 7.0 cm or less, and more than 30 days since acute myocardial infarction. All echocardiograms were independently scored by a core laboratory. Reduction annuloplasty was achieved by device annuloplasty. Two patients underwent immediate intraoperative conversion to a valve replacement because reduction annuloplasty was unable to correct mitral regurgitation; as-treated results are presented., Results: Thirty-day mortality was 4.1% (3/73). Patients received an average of 2.8 bypass grafts. Mean follow-up was 24.6 months. Mitral regurgitation was reduced from 2.6 ± 0.8 preoperatively to 0.3 ± 0.6 at 2 years. Freedom from death or valve reoperation was 78% ± 5% at 2 years. There was significant improvement in ejection fraction and New York Heart Association class with reduction of left ventricular end-diastolic dimension. Cox regression analyses suggested that increasing age (P = .001; hazard ratio, 1.16 per year; 95% confidence interval, 1.06-1.26) and renal disease (P = .018; hazard ratio, 3.48; 95% confidence interval, 1.25-9.72) were associated with decreased survival., Conclusions: Coronary artery bypass grafting + reduction annuloplasty for functional ischemic mitral regurgitation predictably reduces mitral regurgitation and relieves symptoms. This treatment of moderate to severe mitral regurgitation is associated with improved indices of ventricular function, improved New York Heart Association class, and excellent freedom from recurrent mitral insufficiency. Although long-term prognosis remains guarded, this multicenter study delineates the intermediate-term benefits of such an approach., (Copyright © 2011 The American Association for Thoracic Surgery. Published by Mosby, Inc. All rights reserved.)

Functional mitral regurgitation or functional tricuspid regurgitation most commonly result from maladaptive remodeling due to ischemic heart disease or idiopathic dilatative cardiomyopathy. We report a case of significant functional mitral regurgitation and functional tricuspid regurgitation arising from isolated annular dilatation secondary to atrial fibrillation and associated atrial remodeling. The patient underwent successful mitral and tricuspid valve repair and a bi-atrial Maze procedure., (Copyright © 2010 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)

Purpose: We developed a novel, highly articulated robotic surgical system (CardioARM) to enable minimally invasive intrapericardial therapeutic delivery through a subxiphoid approach. We performed preliminary proof of concept studies in a porcine preparation by performing epicardial ablation., Description: CardioARM is a robotic surgical system having an articulated design to provide unlimited but controllable flexibility. The CardioARM consists of serially connected, rigid cyclindrical links housing flexible working ports through which catheter-based tools for therapy and imaging can be advanced. The CardioARM is controlled by a computer-driven, user interface, which is operated outside the operative field., Evaluation: In six experimental subjects, the CardioARM was introduced percutaneously through a subxiphoid access. A commercial 5-French radiofrequency ablation catheter was introduced through the working port, which was then used to guide deployment. In all subjects, regional ("linear") left atrial ablation was successfully achieved without complications., Conclusions: Based on these preliminary studies, we believe that the CardioARM promises to enable deployment of a number of epicardium-based therapies. Improvements in imaging techniques will likely facilitate increasingly complex procedures.

Robotic assistance enhances conventional endoscopy; yet, limitations have hindered its mainstream adoption for cardiac surgery. HeartLander is a miniature mobile robot that addresses several of these limitations by providing precise and stable access over the surface of the beating heart in a less-invasive manner. The robot adheres to the heart and navigates to any desired target in a semiautonomous fashion. The initial therapies considered for HeartLander generally require precise navigation to multiple surface targets for treatment. To balance speed and precision, we decompose any general target acquisition into navigation to the target region followed by fine positioning to each target. In closed-chest, beating-heart animal studies, we demonstrated navigation to targets located around the circumference of the heart, as well as acquisition of target patterns on the anterior and posterior surfaces with an average error of 1.7 mm. The average drift encountered during station-keeping was 0.7 mm. These preclinical results demonstrate the feasibility of precise semiautonomous delivery of therapy to the surface of the beating heart using HeartLander.

Objective: We sought to promote myocardial repair using urinary bladder matrix incorporated with a fusion protein that combined hepatocyte growth factor and fibronectin collagen-binding domain in a porcine model. Collagen-binding domain acted as an intermediary to promote hepatocyte growth factor binding and enhance hepatocyte growth factor stability within urinary bladder matrix., Methods: Urinary bladder matrix incorporated with collagen-binding domain and hepatocyte growth factor was implanted into the porcine right ventricular wall (F group) to repair a surgically created defect. Untreated urinary bladder matrix patches (U group) and Dacron patches (D group) served as controls (N = 5/group). Electromechanical mapping was performed 60 days after surgery. Linear local shortening was used to assess regional contractility, and electrical activity was recorded., Results: Linear local shortening was significantly improved in the F group compared with controls (F: 0.51% +/- 1.57% [P < .05], U: -1.06% +/- 1.84%, D: -2.72% +/- 2.59%), whereas it was inferior to the normal myocardium (13.7% +/- 4.3%; P < .05). Mean electrical activity was 1.49 +/- 0.82 mV in the F group, which was statistically greater than in the control groups (U: 0.93 +/- 0.71 mV; D: 0.30 +/- 0.22 mV; P < .05) and less than the normal myocardium (8.24 +/- 2.49 mV; P < .05). Histologic examination showed predominant alpha-smooth muscle actin positive cells with the F group showing the thickest layer and the D group showing the thinnest layer, with an endocardial endothelial monolayer. Scattered isolated islands of alpha-actinin positive cells were observed only in the F group, but not in the controls, suggesting the presence of cardiomyocytes., Conclusion: The collagen-binding domain/hepatocyte growth factor/urinary bladder matrix patch demonstrated increased contractility and electrical activity compared with urinary bladder matrix alone or Dacron and facilitated a homogeneous repopulation of host cells. Urinary bladder matrix incorporated with collagen-binding domain and hepatocyte growth factor may contribute to constructive myocardial remodeling.

Surgical removal or epicardial radiofrequency ablation of the left atrial appendage (LAA) is occasionally required when endocardial ablations fail. We report a modified minimally invasive surgical approach for elimination of recurrent atrial arrhythmias arising from the LAA, including both radiofrequency ablation and appendectomy. Ablation of the LAA base was performed using the Medtronic Cardioblate bipolar radiofrequency device (Medtronic, Minneapolis, MN), and left atrial appendectomy was then completed using the EndoGIA stapling system (US Surgical, Norwalk, CT). This procedure successfully isolated and removed the tachycardia focus, and normal sinus rhythm was restored. Elimination of LAA arrhythmias using a combination of epicardial radiofrequency ablation and appendectomy ensures electrical isolation while minimizing surgical invasiveness.

A patient presenting with a history of transient ischemic attacks was initially diagnosed with a large secundum-type atrial septal defect by transesophageal echocardiography. Subsequent attempts to percutaneously repair the defect using an Amplatzer septal occlude device (AGA Medical, Plymouth, MN) failed to position correctly on multiple attempts. At the time of surgery, a largely deficient and highly fenestrated septum primum was found, which was likely the cause of the Amplatzer device (AGA Medical) failure. The defect was then definitively repaired using a bovine pericardial patch without incident.

We report a novel subxiphoid video pericardioscopy approach for epicardial mapping that allows direct visualization of the epicardium with minimal use of fluoroscopy. The FLEXview system (Boston Scientific Cardiac Surgery, Santa Clara, CA), which is capable of a free navigation around the heart owing to its flexible neck, was inserted into the pericardial space through a small subxiphoid incision. A commercially available mapping catheter advanced through the working port of the device could be navigated around virtually the entire biventricular epicardial surface. The subxiphoid video pericardioscopy approach using the FLEXview system provided adequate visualization and access to the epicardium of both ventricles for electroanatomic mapping while minimizing surgical invasiveness.

Objective: The cut-and-sew Cox-Maze procedure is the gold standard for surgical treatment of atrial fibrillation, but it is associated with long-term impairment of left atrial mechanical function. We developed a bipolar, irrigated radiofrequency ablation device. We hypothesized that beating heart radiofrequency left atrial ablation would result in minimal acute changes in left atrial hemodynamics., Methods: Six healthy subjects were studied. Combination pressure-conductance catheters were inserted into the left atrium and ventricle. With the use of the device, atrial ablation was performed on the beating heart without cardiopulmonary bypass, including electrical isolation of the posterior left atrium and atrial appendage myocardium. Simultaneous left-sided heart pressure-volume and intracardiac echocardiography data were acquired before ablation, after left atrial appendage ablation alone, and after all ablation (with and without appendage occlusion). The derived indices of left-sided heart mechanical function were examined., Results: Relative to baseline, no significant diminishment in pressure-volume or intracardiac echocardiography-derived indices of global left-sided heart mechanical function were observed after ablation, with or without appendage occlusion. Mitral valve morphology and function were not significantly altered. A significant diminishment of atrial appendage systolic flow was noted after appendage ablation in association with spontaneous echocardiographic contrast in this region., Conclusions: In this model, ablation does not seem to compromise global left-sided heart mechanical function. However, these findings mask regional diminishment in atrial appendage systolic function. This observation demonstrates that electrical isolation of the appendage should be accompanied by its occlusion or excision. Appendage occlusion after ablation does not seem to compromise left-sided heart mechanical function.

Objective: Extracellular matrix scaffolds have been successfully used for myocardial wall repair. However, regional functional evaluation (ie, contractility, electrical conductivity) of the extracellular matrix scaffold during the course of remodeling has been limited. In the present study, we evaluated the remodeled scaffold for evidence of electrical activation., Methods: The extracellular matrix patch was implanted into the porcine right ventricular wall (n = 5) to repair an experimentally produced defect. Electromechanical mapping was performed with the NOGA system (Biosense Webster Inc, Diamond Bar, Calif) 60 days after implantation. Linear local shortening was recorded to assess regional contractility. After sacrifice, detailed histologic examinations were performed., Results: Histologic examinations showed repopulation of the scaffold with cells, including a monolayer of factor VIII-positive cells in the endocardial surface and multilayered alpha-smooth muscle actin-positive cells beneath the monolayer cells. The alpha-smooth muscle actin-positive cells tended to be present at the endocardial aspect of the remodeled scaffold and at the border between the remodeled scaffold and the normal myocardium. Electromechanical mapping demonstrated that the patch had low-level electrical activity (0.56 +/- 0.37 mV; P < .0001) in most areas and moderate activity (2.20 +/- 0.70 mV; P < .0001) in the margin between the patch and the normal myocardium (7.58 +/- 2.23 mV)., Conclusions: The extracellular matrix scaffolds were repopulated by alpha-smooth muscle actin-positive cells 60 days after implantation into the porcine heart. The presence of the cells corresponded to areas of the remodeling scaffold that showed early signs of electrical conductivity.

This article describes the development and preliminary testing of a mobile robotic device to facilitate minimally invasive beating-heart intrapericardial intervention. The HeartLander robot will be introduced beneath the pericardium via subxiphoid incision, adhere to the epicardium, navigate to any location, and administer therapy under the control of the physician. As compared to current robotic cardiac surgical techniques, this novel paradigm obviates immobilization of the heart and eliminates access limitations. Furthermore, it does not require lung deflation and differential ventilation and thus could enable outpatient cardiac surgery. The current HeartLander prototypes use suction to maintain prehension of the epicardium and wire actuation to perform locomotion. A fiber optic videoscope displays visual feedback to the physician, who controls the device through a joystick interface. The initial prototype demonstrated successful prehension, turning, and locomotion on open-chest, beating-heart porcine models where the pericardium was removed (N = 3). A smaller second-generation prototype with an injection system demonstrated locomotion and myocardial injection of dye, both performed with the pericardium intact (N = 3). These trials illustrate the feasibility of using a miniature mobile robot to navigate upon the beating heart and perform intrapericardial therapy.

Objective: A technique for mimicking left atrial atriotomies using an ablation device that can be deployed without cardiopulmonary bypass has been developed., Methods: In 12 healthy large (35-50 kg) adult pigs, maze-like ablation lesions were directly applied to the left atrial epicardium on the beating heart. The ablation device is irrigated, with a bipolar "hemostat" morphology, utilizing radiofrequency energy. Prior to and after ablation, left atrial electromechanical properties were measured during sinus rhythm in the latest 5 pigs using percutaneous endocardial catheter electromechanical mapping and intracardiac echocardiography. Pathologic analysis was performed acutely., Results: All ablation lesions demonstrated conduction block along their entire course. Global left atrial conduction time (49.4 +/- 8.8 milliseconds before vs 58.8 +/- 9 milliseconds after) and pattern were not significantly altered. Although a significant amount (17.12% +/- 9%) of myocardium was either ablated or electrically isolated, ablation was not associated with significant alterations in global left atrial mechanics (left atrium ejection fraction 19% before vs 17% after; pulmonary vein peak flow velocity 1.22 m/s before vs 1.38 m/s after; peak mitral inflow velocity 2.34 m/s before vs 2.64 m/s after), mitral valve function, nor left ventricular function. There was no evidence of atrial thrombus formation. Transmurality was achieved in most lesions with no evidence of charring or barotrauma., Conclusions: Utilizing this ablation device, atrial lesions similar to the left component of the Maze procedure were deployed with uniform success in a beating heart without cardiopulmonary bypass or atriotomy and without adverse effects on left atrial electromechanics.

Background: Lung volume reduction surgery (LVRS) has been demonstrated to provide symptomatic relief and to improve lung function in patients with end-stage emphysema. The goal of this study was to assess the additional morbidity associated with lung transplantation after LVRS for end-stage emphysema with regard to immediate postoperative outcomes, longitudinal spirometry, and survival rates compared to an age-, gender-, procedure-matched, and transplant time-matched cohort that had lung transplantation alone., Methods: We compared the postoperative and long-term outcomes of a sequential procedure cohort to a matched cohort to assess the possible added post-transplant morbidity., Results: Fifteen patients who underwent sequential LVRS (including 11 unilateral LVRS, 4 bilateral LVRS) and lung transplantation (ipsilateral in 7 and contralateral in 8) on average 28.1 +/- 17.2 months (median, 27.4 months; range, 3.7 to 61.7 months) later were assessed. No significant differences were noted in pretransplant demographics, post-transplant variables, longitudinal spirometric indices, or survival. A trend toward a lower pretransplant arterial carbon dioxide tension was apparent in the sequential procedure cohort. Group analysis revealed a significant increase in the number of patients requiring transfusion and in the total number of units transfused in patients undergoing ispsilateral transplantation after LVRS; a significant increase in the length of intensive care unit stay; and a trend toward an increase in the duration of hospital stay in patients undergoing lung transplantation within 18 months of LVRS., Conclusions: In appropriate candidates, LVRS bridged the time to transplantation by an average of 28.1 +/- 17.2 months (median, 27.4 months; range, 3.7 to 61.7 months) without significantly increasing post-transplant morbidity or mortality. Furthermore, bilateral LVRS bridged the time to transplantation to a greater extent than unilateral LVRS (34.9 +/- 29.8 months; median, 32.1 months versus 25.4 +/- 16.3 months; median, 22.3 months; p = 0.23).

We hypothesized that a high-quality anastomosis between the left internal thoracic artery and the left anterior descending coronary artery could be constructed off-pump using a 4-degrees-of-freedom robotic telemanipulation system, endoscopic myocardial stabilization, and two-dimensional visualization. Nine swine were used. Three ports were created on the left chest for the endoscope and the two robotic arms, and another port was created on the right chest for the endostabilizer. Quality of anastomosis was assessed by angiography, analysis of flow, survival after proximal coronary ligation, and histopathology. All nine anastomoses were completed successfully in 22 +/- 3.6 minutes without the need for repair stitches. Left internal thoracic artery flow was 21.6 +/- 2.5 ml/min with diastolic dominant pattern. Eight animals (89%) survived for 60 minutes with the proximal left anterior descending coronary ligated. Angiographic patency was 100% with Fitzgibbon grade A in all. Histopathology of the anastomosis demonstrated minor changes in the integrity of the endothelium and the internal elastic lamina and absence of medial necrosis. We have demonstrated in our robotic off-pump coronary bypass model that a high-quality anastomosis can be constructed between the left internal thoracic artery and the left anterior descending coronary artery. These results support continued research towards robotic endoscopic off-pump CABG., (Copyright 2002 Wiley-Liss, Inc.)

Implications: This report describes the use of high-thoracic epidural anesthesia for a patient undergoing minimally invasive direct coronary artery bypass.