Endoscopic Coronary Bypass Grafting Research Articles

How to advance from minimally invasive coronary artery bypass grafting to totally endoscopic coronary bypass grafting: challenges in Europe versus United States of America.

Robotic coronary and intra-cardiac surgery has been available for more than 25 years. In this period, multiple studies have demonstrated the beneficial effects of robotic surgery over conventional open surgery. Throughout the years, technical developments have enabled us to perform totally endoscopic coronary artery bypass (TECAB) grafting. But these techniques remained in the hands of a small group of pioneers because of a lack of structured training programs and the absence of long-term results at that time. Currently, a renewed interest and a wide dispersion of robotic platforms, thanks to use of robotics in other disciplines, has led to an exponential increase in robotic cardiac centers both in Europe and USA. Nonetheless, this increase was slowed down in Europe as a result of the uncertainty introduced by the implementation of a revised regulatory framework for medical devices [Regulation 2017/745, 'Medical Device Regulation' ('MDR')]. The MDR was introduced with the goal of increasing patient safety and supporting innovation. Implementing the MDR has proven to be exceptionally challenging and risks to the supply of essential devices have been identified. Changes to both regulatory and market dynamics led to a circumstance where the only available robotic platform for cardiac surgery decided to cease marketing of essential accessories for conducting surgery. This resulted in the disappearance of dedicated tools such as the Endowrist stabilizer, essential for TECAB, and the atrial retractor which is essential for intra-cardiac surgery. In the mean-time, further clinical evidence was published demonstrating the superiority of robotic cardiac surgery over other minimally invasive approaches. This has demonstrated the need to better define the clinical evidence requirements for regulatory purposes to ensure that dedicated tools for evidence-based interventions in robotic coronary surgery remain available such that TECAB can continue in Europe.

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

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. 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. 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). 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.

Robotic Totally Endoscopic Coronary Artery Bypass Grafting in Men and Women: Are There Sex Differences in Outcome?

According to several studies, women are at higher risk for mortality and experience less relief of angina after coronary artery bypass graft surgery (CABG) than men. Sex-related differences in patients undergoing totally endoscopic coronary bypass grafting (TECABG) have not been investigated thus far. The aim of the present study was to evaluate the impact of sex on the outcome of patients undergoing TECABG. The data of 500 consecutive patients (364 male, 136 female) undergoing TECABG using the da Vinci telemanipulation system (Intuitive Surgical, Sunnyvale, CA) from 2001 to 2011 at two institutions were investigated regarding sex-related differences in short-term and long-term outcome. In all, 334 single, 150 double, 15 triple, and 1 quadruple TECABG procedures were carried out. Female patients were significantly older (63 years [range, 26 to 90] versus 59 years [range, 31 to 85], p = 0.001) and had higher European System for Cardiac Operative Risk Evaluation score levels (3 [range, 0 to 11] versus 2 [range, 0 to 13], p < 0.001). Male patients received slightly more grafts (1 [range, 1 to 4] versus 1 [range, 1 to 3], p = 0.028), female patients were more likely to undergo beating heart surgery (20% versus 28%, p = 0.042). In-hospital mortality was 3 of 364 men (0.8%) and 2 of 136 women (1.5%; p = 0.513). Comparison of long-term-survival revealed 1-, 3- and 5-year survival rates of 96%, 96%, and 95% in men and 96%, 96%, and 96% in women, respectively, without any significant difference. Analysis of freedom from major adverse cardiac and cerebrovascular events revealed 1-, 3-, and 5-year rates of 86%, 84%, and 82% in men and 85%, 81%, and 81% in women, respectively, without any significant difference. Our data show that women undergoing TECABG have outcomes similar to those of men.

Robotic internal thoracic artery harvesting and the mid-term follow up of arterial graft patency

To summarize our experience of robotic internal thoracic artery (ITA) skeletonized harvesting in Asian patients and evaluate the learning curves of robotic ITA harvesting and ITA graft patency. A total of 200 patients underwent totally robotic ITA takedown at our department from April 2007 to August 2012. ITA was harvested in a skeletonized fashion and learning curve estimated. Coronary artery bypass grafting was completed in minimally invasive direct coronary artery bypass graft (MIDCAB) or totally endoscopic coronary bypass graft on beating heart (BH-TECAB) manners after robotic ITA harvesting. The coronary angiography or 64-MSCT was performed to evaluate the patency of ITA graft before discharge and at Year 1-5 postoperatively. One patient underwent median sternotomy for severe plural adhesion. Left ITA (LITA, n = 190), right ITA (RITA, n = 5) and double-ITA (n = 4) were harvested. The mean duration of single ITA harvesting was 18-70 (35.8 ± 10.7) min. A significant learning curve was observed: y (min) = 58.0 - 5.3×ln(x) (r(2) = 0.33, P < 0.01). ITA patency was 98.1% at Year 1 and 97.8% at Year 2 postoperatively respectively. And there was no recurrence of ITA occlusion at Years 3-5. Robotic ITA takedown is a prerequisite for totally endoscopic coronary bypass graft and can be performed safely and within an acceptable time after overcoming a learning curve. ITA graft patency has comparable outcomes of conventional surgery.

A Step toward Nonrobotic Total Endoscopic Coronary Bypass Grafting: 40 Coronary Anastomoses in a Biomechanical Beating Heart Model

A Step toward Nonrobotic Total Endoscopic Coronary Bypass Grafting: 40 Coronary Anastomoses in a Biomechanical Beating Heart Model

A Step toward Nonrobotic Total Endoscopic Coronary Bypass Grafting: 40 Coronary Anastomoses in a Biomechanical Beating Heart Model

Nonrobotic total endoscopic coronary bypass grafting is commonly considered as technically too difficult. After endoscopic practicing in a simple box model, we questioned this statement in a more sophisticated training model. In a handmade chest model containing a mechanically actuated porcine heart, anastomoses between homologous vein and shunted anterior coronary artery were performed using Prolene 7-0 sutures or U-clips in 20 anastomoses each. Commercially available endoscopic instruments and exclusive two-dimensional endoscopic vision were used. As quality control, the procedures were recorded, flow was measured, indocyanine green dye angiograms were performed, vinylpolysiloxane endocasts were produced, and finally the anastomoses were assessed from the endothelial side. Three-dimensional computed tomographic reconstruction was explored for cast measuring. All anastomoses were completed successfully in a time of 51 ± 14 minutes (Prolene) and 48 ± 10 minutes (U-clips). Despite suboptimal equipment, a reproducible sequence of the procedure was established and documented. Improving surgical performance was reflected in a reduction in anastomotic leakage and time requirement. The quality assessment protocol showed a learning curve and problems itself, which are briefly discussed. A beating heart model is an adamant requirement of training for the technically demanding procedure of nonrobotic total endoscopic coronary bypass grafting. Refinement of the model and quality assessment as well as expansion of training to other regions of the heart should prepare for a cost-effective, broad-based clinical application of nonrobotic endoscopic techniques in coronary surgery. Available high-definition three-dimensional vision systems and the development of appropriate (articulating) instruments will make the procedure safer and quicker and will cut the learning curve.

Model based heart motion estimation for robotic surgery

Objectives: In order to synchronize robotic surgical instruments during totally endoscopic coronary bypass grafting with the heart motion the estimation of the position of the intervention point is required. In this study a model-based heart motion estimator is presented and validated in beating artificial heart model.

Minimally invasive robotic coronary bypass on the beating heart using da Vinci S system

To summarize the experience of minimally invasive robotic coronary bypass on beating heart using da Vinci S in China. Fifty-six patients underwent selected robotic coronary bypass on beating heart from April 2007 to December 2008. All the patients had history of angina and the coronary arteriography showed severe stenosis in the left anterior descending artery (LAD), of which 10 cases had right coronary artery or left circumflex coronary (LCX) stenosis. The age was 33 to 74 years old, with a mean of (55.8 +/- 9.4) years old. The weight was (71.4 +/- 13.2) kg. All the patients had good lung function and had no medical history of pleurisy and thoracic surgery. CT scan of double internal thoracic artery (ITA) was routinely checked preoperatively. The procedures included: (1) The robotically assisted endoscopic atraumatic coronary artery bypass surgery. The approach was via a small left anterior thoracotomy (6 to 8 cm) after robotic ITA was taken down. The ITA was manually anastomosed to the LAD or LCX on beating heart. (2) Totally endoscopic coronary bypass graft on beating heart. After ITA harvesting, the endo stabilizer was inserted via the fourth port in the xiphoid area under endoscopic vision. The left ITA to the LAD grafting was done using U-clips on beating heart in a totally endoscopic manner using da Vinci S system through 4 ports. For all patients the ITA flow was checked by the Doppler flowmeter after anastomosis was completed. After the surgery was completed, the thoracic port was checked carefully to avoid bleeding. The operating procedures and a variety of clinical parameters were recorded and analyzed. (3) Stent placement after robotic surgery in a hybrid manner. The graft patency rate was evaluated by CT or arteriography. All patients successfully accepted robotic minimally invasive coronary bypass on the beating heart using da Vinci S surgical system without complications. The mean graft flow was (23.2 +/- 16.7) ml/min. And there was no surgical conversion and surgical death. Fifty-three patients received ITA to LAD grafts and 3 patients received double coronary artery bypass grafts as well. Ten cases received stent placement in separate session. The CT scan and angiography revealed patent grafts in all patients. There were no post-operative complications. All patients were discharged from hospital. As a new advanced approach of revascularization, robotic ITA harvesting and coronary anastomoses can be safely performed with the da Vinci S system. The procedure is minimally invasive and can offer enhanced ability to control precise and stable operative manipulations.

The 3rd hand – a simple but useful tool for beating heart total endoscopic coronary bypass grafting (BH-TECAB)

The transition to totally endoscopic arterial bypass grafting (TECAB) by computer enhanced instrumentation systems brings the loss of an assisting hand for grasping the pedicle of the internal thoracic artery (ITA) and holding the threads, since only two robotic arms are positioned in the thoracic cavity. That is why exact planning of every step during surgery is mandatory. Especially the positioning of the IMA pedicle during beating heart procedures is imperative for friction-free workflow during the anastomosis. Stay sutures may partially overcome this problem. However, the pedicle hanging on stay sutures still tends to sway around, repositioning is limited. To aid in better workflow, we developed an easy-to-use and cheap holder for the IMA pedicle without the need of any additional port. By inserting a steel wire through the stabilizing system, the pedicle can be easily fixed onto it thus positioned and repositioned wherever it is needed during sewing the anastomosis.

The ESTECH Remote Access Perfusion Cannula in Minimally Invasive Cardiac Surgery

Peripheral access cardiopulmonary bypass (CPB) and endoclamping of the aorta are prerequisites for performance of minimal access or totally endoscopic cardiac surgery on the arrested heart. We present our experience with the ESTECH remote access perfusion (RAP) cannula in arrested-heart totally endoscopic coronary bypass grafting (AHTECAB) and atrial-septal defect (ASD) repair via minithoracotomy and totally endoscopic ASD repair. Remote access CPB was performed in 30 patients (17 male), with a median age of 56 years (range, 21-70 years) using the ESTECH RAP cannula. Preoperatively all patients received a thoracic and abdominal CT scan. Operations were 20 AHTECAB, 5 ASD repair via minithoracotomy, and 5 robotically assisted totally endoscopic ASD repairs. Intraoperatively the patients were monitored by transesophageal echocardiography and bilateral radial artery pressure lines for correct placement of the balloon in the ascending aorta. Neither vascular perforation nor dissection of the aorta occurred during these surgeries. Full CPB was achieved in all patients. Because of location in a supraaortic branch fluoroscopic visualization of the guide wire was necessary in 2 of 30 cases. Once the aortic occlusion balloon was placed, repositioning was required in none of our cases. In one AHTECAB case rupture of the balloon occurred before starting the anastomosis. The cannula was replaced and the AHTECAB could be finished without complications. In one patient inguinal wound infection occurred, which was successfully revised surgically. No perioperative myocardial ischemia, stroke, or critical leg ischemia occurred, and no hospital death occurred. CPB and cardiac arrest can adequately be performed via a femoral access in minimally invasive cardiac surgery using the ESTECH RAP system. Intense preoperative patient evaluation and intraoperative monitoring are absolute prerequisites for safe application of the technique.

Coronary bypass grafting with the computer motion system

The ZEUS robotic microsurgical system (Computer Motion, Inc., Goleta, CA) has been used in the United States, Canada, and Europe to perform coronary bypass grafting. Initial procedures were done on the arrested heart using either a median sternotomy and conventional cardiopulmonary bypass, or using the Heartport system (Heartport, Inc, Redwood City, CA) and a minimally invasive incision.1Boehm DH Reichenspurner H Gulbins H et al.Early experience with robotic technology for coronary artery surgery.Ann Thorac Surg. 1999; 68: 1542-1546Abstract Full Text Full Text PDF PubMed Scopus (78) Google Scholar Recently, Dr. Herman Reichenspurner and Dr. Douglas Boyd have used the robotic system to perform coronary bypass grafting on the beating heart.2Boyd WD Rayman R Desai ND et al.Closed-chest coronary artery bypass grafting on the beating heart with the use of a computer-enhanced surgical robotic system.J Thorac Cardiovasc Surg. 2000; 120: 807-809Abstract Full Text Full Text PDF PubMed Scopus (96) Google Scholar, 3Reichenspurner H Boehm DH Gulbins H et al.Robotically assisted endoscopic coronary artery bypass procedures without cardiopulmonary bypass.J Thorac Cardiovasc Surg. 1999; 118: 960-961Abstract Full Text Full Text PDF PubMed Scopus (40) Google Scholar Dr. Boyd has accumulated a series of 17 patients who have undergone complete endoscopic coronary bypass grafting on the beating heart using the ZEUS system. The recommended training regimen with this system includes 80 to 100 hours of practice in inanimate models, live animals, and cadavers. Clinical sites are required to prove their mastery of predetermined skill drills that are carefully reviewed before proceeding to the next developmental stage. Initially, it is recommended that a center without previous robotic experience begin their clinical cases through a full sternotomy. This provides an excellent safety margin for the patient and allows the surgical team to become familiar with endoscopic surgery. Endoscopic experience increases gradually by requiring centers to first perform a series of robotically assisted endoscopic internal thoracic artery harvests. In these initial cases, the surgeon completes the anastomosis by hand. This format increases endoscopic learning and readies the surgeon and surgical team to perform a completely endoscopic case. Once the surgical team has had sufficient experience and is comfortable with endoscopic internal thoracic artery takedown and the anastomotic technique, the sternotomy and left thoracotomy may be abandoned. The surgeon can then proceed to performing a total endoscopic bypass graft procedure. Here, we describe the steps in performing a robotically assisted endoscopic anastomosis of the left internal thoracic artery (LITA) to the left anterior descending (LAD) coronary artery using either an anterior thoracotomy or a partial or total median sternotomy. We then describe the steps involved in totally endoscopic coronary bypass grafting.