Defining the Learning Curve for Robotic-Assisted Endoscopic Harvesting of the Left Internal Mammary Artery

The Current State of Hybrid Coronary Revascularization

Hybrid coronary revascularization (HCR) combines a minimally invasive surgical approach with percutaneous coronary intervention (PCI) for the treatment of multivessel coronary artery disease. Despite decades of use, widespread acceptance has been limited. In this review, we conduct a comparative assessment of HCR in relation to traditional coronary artery bypass graft surgery and multivessel PCI. Although large-scale randomized data are still lacking, numerous studies have demonstrated that HCR may offer benefits regarding resource utilization and short-term morbidity while delivering comparable mid- and long-term survival compared with traditional bypass surgery. Compared with PCI, HCR may offer similar periprocedural morbidity while mitigating the need for repeat revascularization by providing a surgical arterial bypass graft to the left anterior descending artery.

The Current Status of Minimally Invasive Conduit Harvesting for Coronary Artery Bypass Grafting

The harvesting of conduits for coronary artery bypass surgery has evolved over the last decade to include endoscopic approaches to access the saphenous vein, radial artery, and internal mammary artery. These minimally invasive techniques reduce the morbidity associated with open procedures by decreasing pain and recovery time and increasing mobility post operatively. This review highlights the differences in morbidity, quality, and patency between the most common conduits that are harvested minimally invasively for coronary artery bypass grafting surgery.

Subcostal bilateral internal thoracic artery harvesting with the da Vinci Single Port system: an experimental feasibility study

We evaluated the feasibility of harvesting bilateral internal thoracic arteries with the da Vinci Single Port system (SP) through a single left-sided subcostal incision. Complete bilateral mobilization with sufficiently long conduits for multivessel grafting was possible in 2 human cadavers and 2 live porcine. Creating the subcostal access and docking the SP system took between 14 and 21 min and the total harvest time ranged from 65 to 125 min in all models. No major bleeding was observed in the live porcine and hemostasis was managed with the available instrumentation. One porcine deceased during surgery due to ventricular fibrillation followed by cardiac arrest. The robotic harvesting was technically easily reproduced by the surgeons and required no additional rib-spreading. Further studies will be required to assess if this subcostal approach with the da Vinci SP system yields true clinical benefits in patients.

Minimal invasive coronary surgery is not associated with increased mortality or morbidity during the period of learning curve

BACKGROUND

Minimally invasive procedures for coronary revascularization have been performed for over 20 years; however, their technical complexity, steep learning curves and absence of training programs explain the weak acceptance of these techniques. The aim of this study is to describe the step-by-step learning process on how to establish a minimally invasive coronary artery revascularization program. The short-term outcomes of our first 30 patients were compared to our left internal mammary artery (LIMA) to left anterior descending (LAD) artery off pump coronary artery bypass (OPCAB) cohort as a quality control baseline.

METHODS

All patients who benefited from an endoscopic atraumatic coronary artery bypass (Endo-ACAB) in our hospital, from July 2018 to May 2020 (n = 30) were identified. Baseline demographics, peri, postoperative and laboratory data were extracted from each patient's medical records. These results were compared to our LIMA-LAD OPCAB cohort (n = 23).

RESULTS

Twenty-eight patients were planned for a single LIMA-LAD Endo-ACAB. The remaining two had a T-graft double Endo-ACAB. Ten patients had a hybrid revascularization with the culprit lesion being treated first. Three patients were converted to sternotomy because of a LIMA lesion during thoracoscopic harvesting. We accounted three major adverse cardiovascular events (MACE). Demographic, peri and postoperative data showed no significant differences between the Endo-ACAB and the OPCAB group.

CONCLUSION

Endo-ACAB is a technically demanding operation, however, it can safely be introduced in centers with no previous experience with no extra cost in terms of morbidity or mortality. Thoracoscopic LIMA harvesting is the most demanding surgical skill to acquire.

Minimally Invasive Direct Coronary Artery Bypass: An Evolving Paradigm Over the Past 25 Years

OBJECTIVE

We have routinely utilized minimally invasive direct coronary artery bypass (MIDCAB) for revascularization of the left anterior descending (LAD) coronary artery. We examined how this procedure has evolved.

METHODS

A retrospective review was undertaken of 2,283 consecutive patients who underwent MIDCAB between 1997 and 2021. Patients were divided into 3 groups: group A from 1997 to 2002 (n = 751, 32.9%), group B from 2003 to 2009 (n = 452, 19.8%), and group C from 2009 to 2021 (n = 1,080, 47.3%). Risk profiles and short-term outcomes were analyzed for the entire cohort and for 293 propensity-matched patients drawn from each group.

RESULTS

The left internal mammary artery was harvested open in group A but with robotic assistance in group C. Thirty-day mortality was higher in group A versus group C (12 deaths, 1.6% vs 5 deaths, 0.5%, P = 0.044); this difference was negated after propensity matching. Group A had more comorbidities than group C, including peripheral vascular disease (17.7% vs 10.0%, P < 0.001), congestive heart failure (39.6% vs 18.0%, P < 0.001), and a history of stroke (17.9% vs 10.0%, P < 0.001), although diabetes mellitus was more common in group C (51.4% vs 31.0%, P < 0.001). Stroke was greater in group A (1.2% vs 0.0% vs 0.2%, respectively, P = 0.004), as was the need for prolonged ventilation (3.6% vs 0.2% vs 0.9%, respectively, P < 0.001), before and after propensity matching.

CONCLUSIONS

MIDCAB patients had less comorbidities than in the past. Robot-assisted MIDCAB was associated with lower stroke risk.

Minimally invasive left internal mammary artery harvesting techniques during the learning curve are safe and achieve similar results as conventional LIMA harvesting techniques

Background

Internal thoracic arteries (ITAs) are considered to be the standard conduits used for coronary revascularization. Recently minimally invasive procedures are performed to harvest ITAs. The aim of this retrospective cohort study is to observe the effect and safety of less invasive LIMA harvesting approaches in the learning curve compared to conventional harvesting.

Methods

We retrospectively analyzed the data of 138 patients divided into three different groups based on the LIMA harvesting techniques: conventional sternotomy LIMA harvesting, CSLH (n: 64), minimally invasive direct LIMA harvesting, MIDLH (n: 42), and robotic-assisted LIMA harvesting, RALH (n: 32). The same 138 patients were also divided into sternotomy (n: 64), and non-sternotomy (n: 74) groups keeping both MIDLH and RALH in the non-sternotomy category. Parameters associated with LIMA’s quality and some other perioperative parameters such as harvesting time, LIMA damage, perioperative myocardial infarction, ventilation time, 24 h drainage, ICU stay, hospital mortality, computed tomographic angiography (CTA) LIMA patency on discharge, and after one year were recorded.

Results

The mean LIMA harvesting time was 36.9 ± 14.3, 74.4 ± 24.2, and 164.7 ± 51.9 min for CSLH, MIDLH, and RALH groups respectively (p < 0.001). One patient 1/32 (3.1%) in the RALH group had LIMA damage while the other two groups had none. One-month LIMA CTA patency was 56/57 (98.2%), 34/36 (94.4%), and 27/27 (100%) (p = 0.339), while 1 year CTA patency was 47/51 (92.1%), 30/33 (90.9%), and 24/25 (96%) for CSLH, MIDLH, and RALH groups respectively (p = 0.754). In the case of sternotomy vs non-sternotomy, the LIMA harvesting time was 36.9 ± 14.3 and 113.6 ± 59.3 min (p < 0.001). CTA patency on discharge was 56/57 (98.2%) and 61/63 (96.8%) (p = 0.619), while 1 year CTA patency was 47/51 (92.1%) and 54/58 (93.1%) (p = 0.850) for sternotomy vs non-sternotomy groups.

Conclusion

Minimally invasive left internal mammary artery harvesting techniques during the learning curve are safe and have no negative impact on the quality of LIMA. Perioperative outcomes are comparable to conventional procedures except for prolonged harvesting time. RALH is the least invasive and most time-consuming procedure during the learning curve. These procedures are safe and can be performed for selected patients even during the learning curve.

The learning curve of robotic coronary arterial bypass surgery: A report from the STS database

BACKGROUND

There is limited data to inform minimum case requirements for training in robotically assisted coronary artery bypass grafting (RA-CABG). Current recommendations rely on nonclinical endpoints and expert opinion.

OBJECTIVES

To determine the minimum number of RA-CABG procedures required to achieve stable clinical outcomes.

METHODS

We included isolated RA-CABG in the Society of Thoracic Surgeons (STS) registry performed between 2014 and 2019 by surgeons without prior RA-CABG experience. Outcomes were approach conversion, reoperation, major morbidity or mortality, and procedural success. Case sequence number was used as a continuous variable in logistic regression with restricted cubic splines with fixed effects. Outcomes were compared between operations performed earlier versus later in case sequences using unadjusted and adjusted metrics.

RESULTS

There were 1195 cases performed by 114 surgeons. A visual inflection point occurs by a surgeon's 10th procedure for approach conversion, major morbidity or mortality, and overall procedural success after which outcomes stabilize. There was a significant decrease in the rate of approach conversion (7.7% and 2.5%), reoperation (18.9% and 10.8%), and major morbidity or mortality (21.7% and 12.9%), as well as an increase in the rate of procedural success (72.9% and 85.3%) with increasing experience between groups. In a multivariable logistic regression model, case sequences of >10 were an independent predictor of decreased approach conversion (odds ratio [OR]: 0.27; 95% confidence interval [CI]: 0.09-0.84) and increased rate procedural success (OR: 1.96; 95% CI: 1.00-3.84).

CONCLUSIONS

The learning curve for RA-CABG is initially steep, but stable clinical outcomes are achieved after the 10th procedure.

The first year is the hardest: a comparison of early versus late experience after the introduction of robotic hiatal hernia repair

While the majority of the literature written concerning minimally invasive hiatal hernia repair involves laparoscopy, little has been written concerning the transition to a robotic technique. We present our experience, with a transparent analysis of data, with regard to the introduction of robotic paraesophageal hernia (PEH) repair by an experienced laparoscopic surgeon. We reviewed our first 30 consecutive patients who underwent robotic PEH over a 2-year period after the introduction of robotic surgery at our institution. Patients were divided into two groups: the early experience group (procedures performed within the first year of introduction of robotic technique, n = 13) and a late experience group (procedures performed in the second year, n = 17). All procedures were performed by a single experienced foregut surgeon. The mean operative time for the early group was significantly greater than for the late group, 184 min versus 142 min, respectively (p < 0.01). Four patients in the early group required conversion to open, while zero patients in the late group required conversion (p = 0.03). Patient demographics and complications did not differ significantly between the two patient populations. The early robotic hiatal hernia repair experience can be more difficult than expected, even in the hands of an experienced laparoscopic team. We identify several areas of improvement including patient positioning, operating room team training, and technical experience. This data can help other surgeons prepare for the transition to robotic foregut surgery.

Nonrobotic Total Endoscopic Coronary Artery Bypass Grafting: A Proof-of-Concept Study in 20 Patients

OBJECTIVE

At present, minimal invasive direct coronary artery grafting is the least invasive nonrobotic surgical approach to revascularize the left anterior descending artery with the left internal mammary artery. Total endoscopic coronary bypass grafting is performed with the help of a telemanipulator ("robot"). A prospective proof-of-concept study was initiated to investigate a nonrobotic total endoscopic coronary bypass grafting approach.

METHODS

Twenty patients with significant left anterior descending artery or left main stem lesion were operated on via three or four left thoracic access ports. Under exclusive endoscopic vision, the left internal mammary artery was harvested and anastomosed to the left anterior descending artery manually. Cardiopulmonary bypass and cardioplegic arrest were planned in all cases.

RESULTS

In 10 patients, the operation was completed successfully as nonrobotic total endoscopic coronary bypass grafting. Reasons for conversions to minimal invasive direct coronary artery grafting or conventional sternotomy were dense pleural adhesions (3 patients), bleeding of the anastomosis (3), diffuse bleeding during left internal mammary artery harvesting (2), identification problems of the target artery (1), or left internal mammary artery failure (1). Postoperative angiography in five primarily successful nonrobotic total endoscopic coronary bypass grafting patients showed patent anastomoses in four cases. One patient was reoperated on for early anastomotic failure in a 1.0-mm target vessel. Until now, a percutaneous coronary intervention of remaining lesions as staged hybrid procedure was performed in three patients (2 nonrobotic total endoscopic coronary bypass grafting, 1 minimal invasive direct coronary artery grafting).

CONCLUSIONS

With a thoroughly surveyed learning curve, nonrobotic total endoscopic coronary bypass grafting procedure could become an alternative to other available treatment options; however, the value of the procedure has to be further investigated.

A systematic review on robotic coronary artery bypass graft surgery

BACKGROUND

Robotic-assisted coronary artery bypass graft surgery (CABG) has been performed over the past decade. Despite encouraging results from selected centres, there is a paucity of robust clinical data to establish its clinical safety and efficacy. The present systematic review aimed to identify all relevant clinical data on robotic CABG. The primary endpoint was perioperative mortality, and secondary endpoints included perioperative morbidities, anastomotic complications, and long-term survival.

METHODS

Electronic searches were performed using three online databases from their dates of inception to 2016. Relevant studies fulfilling the predefined search criteria were categorized according to surgical techniques as (I) totally endoscopic coronary artery bypass without cardiopulmonary bypass (TECAB off-pump); (II) TECAB on-pump; and robotic-assisted mammary artery harvesting followed by minimally invasive direct coronary artery bypass (robotic MIDCAB).

RESULTS

The present systematic review identified 44 studies that fulfilled the study selection criteria, including nine studies in the TECAB off-pump group and 16 studies in the robotic MIDCAB group. Statistical analysis reported a pooled mortality of 1.7% for the TECAB off-pump group and 1.0% for the robotic MIDCAB group. Intraoperative details such as the number and location of grafts performed, operative times and conversion rates, as well as postoperative secondary endpoints such as morbidities, anastomotic complications and long-term outcomes were also summarized for both techniques.

CONCLUSIONS

A number of technical, logistic and cost-related issues continue to hinder the popularization of the robotic CABG procedure. Current clinical evidence is limited by a lack of randomized controlled trials, heterogeneous definition of techniques and complications, as well as a lack of robust clinical follow-up with routine angiography. Nonetheless, the present systematic review reported acceptable perioperative mortality rates for selected patients at specialized centres. These results should be considered as a useful benchmark for future studies, until further data is reported in the form of randomized trials.

Training Assistants Improves the Process of Adoption of Video-Assisted Thoracic Surgery Lobectomy

BACKGROUND

Despite overwhelming evidence of decreased pain, fewer complications, and shorter length of stay with equivalent oncologic outcomes, video-assisted thoracic surgery (VATS) lobectomy has been slow to be adopted in the community. This study evaluates the role of training surgical assistants to ease the transition to VATS lobectomy.

METHODS

A half-day training course for physician assistants in the specific skills needed to assist with VATS lobectomy was developed to be offered annually in conjunction with a national meeting. Each participant completed a needs assessment before the course and a course assessment afterward. One-year follow-up data were obtained from the first cohort to determine the effects of the course on their practice.

RESULTS

Forty-four physician assistants participated in the course in either 2013 or 2014. Participant-identified educational needs included enhanced camera navigation skills, use of specialized instruments, and knowledge of the steps of the operation to provide proactive assistance. After completing the course, 90% (n = 39) felt more confident in their ability to provide optimal visualization for the operating surgeon, and 93% (n = 40) felt more confident in their ability to recognize and anticipate the steps of a VATS lobectomy. These changes persisted at 1 year.

CONCLUSIONS

Specific training directed at surgical assistants may improve the adoption of new technology by mechanisms including improved visualization and better understanding of methods to facilitate the operation and avoid frustration. This type of training should be made available to assistants of surgeons learning new operations.

Robotically assisted coronary artery bypass grafting: a systematic review and meta-analysis

BACKGROUND

It remains uncertain as to whether robotically assisted coronary bypass surgery (RACBS) is superior to non-robotic procedures.

METHODS

Literature searches were conducted using MEDLINE, EMBASE and LILACS. Two review authors independently screened citations, assessed trial quality and performed data extraction.

RESULTS

Three trials met the inclusion criteria. None was randomized. Compared with non-robotic approaches, RACBS was associated with longer surgical times, shorter intensive care unit and hospital stays, higher extubation rates and lower odds for atrial fibrillation as well as myocardial infarction. There were no differences for the odds of stroke and mortality between the interventions.

CONCLUSIONS

Although robotic-assisted coronary bypass appears to be promising, the study designs were not adequate and may have a high risk of selection bias. There is a need for randomized trials to corroborate the findings and to determine the long-term benefits of RACBS compared with traditional surgical approaches.