Technique of closed chest coronary artery surgery on the beating heart

Minimally-invasive cardiac surgery: a bibliometric analysis of impact and force to identify key and facilitating advanced training

Background

The number of citations an article receives is a marker of its scientific influence within a particular specialty. This bibliometric analysis intended to recognise the top 100 cited articles in minimally-invasive cardiac surgery, to determine the fundamental subject areas that have borne considerable influence upon clinical practice and academic knowledge whilst also considering bibliometric scope. This is increasingly relevant in a continually advancing specialty and one where minimally-invasive cardiac procedures have the potential for huge benefits to patient outcomes.

Methods

The Web of Science (Clarivate Analytics) data citation index database was searched with the following terms: [Minimal* AND Invasive* AND Card* AND Surg*]. Results were limited to full text English language manuscripts and ranked by citation number. Further analysis of the top 100 cited articles was carried out according to subject, author, publication year, journal, institution and country of origin.

Results

A total of 4716 eligible manuscripts were retrieved. Of the top 100 papers, the median (range) citation number was 101 (51–414). The most cited paper by Lichtenstein et al. (Circulation 114(6):591–596, 2006) published in Circulation with 414 citations focused on transapical transcatheter aortic valve implantation as a viable alternative to aortic valve replacement with cardiopulmonary bypass in selected patients with aortic stenosis. The Annals of Thoracic Surgery published the most papers and received the most citations (n = 35; 3036 citations). The United States of America had the most publications and citations (n = 52; 5303 citations), followed by Germany (n = 27; 2598 citations). Harvard Medical School, Boston, Massachusetts, published the most papers of all institutions. Minimally-invasive cardiac surgery pertaining to valve surgery (n = 42) and coronary artery bypass surgery (n = 30) were the two most frequent topics by a large margin.

Conclusions

This work establishes a comprehensive and informative analysis of the most influential publications in minimally-invasive cardiac surgery and outlines what constitutes a citable article. Undertaking a quantitative evaluation of the top 100 papers aids in recognising the contributions of key authors and institutions as well as guiding future efforts in this field to continually improve the quality of care offered to complex cardiac patients.

Hemostatic Control of Coronary Arteries with Poloxamer 407 Reverse-Thermal Polymer during Off-Pump Coronary Artery Bypass Surgery in a Pig Model

Objective

To evaluate a new material, poloxamer 407 reversethermal polymer, which may be of value in controlling bleeding during off-pump coronary anastomoses.

Methods

Poloxamer 407 reverse-thermal polymer is a clear, nontoxic compound that is a viscous liquid at room temperature but instantly changes to a firm, water-soluble gel when warmed to body temperature. Six pigs underwent off-pump coronary artery bypass with the left internal mammary artery to the left anterior descending coronary artery. Blood loss from the arteriotomy was measured over a 15-minute period before and after injection of 500 μL intracoronary polymer. After completion of the anastomosis, 10 mL of cold saline was poured along the left anterior descending artery to facilitate dissolution of the polymer. The heart was allowed to beat 2 additional hours with blood flowing through the left internal mammary to left anterior descending graft, after which a completion angiogram was obtained to evaluate graft patency and to look for gross angiographic evidence of coronary branch occlusion or intraluminal filling defects. The animals were then humanely euthanized, and myocardium from the area subtended by the left anterior descending was harvested for histologic evaluation.

Results

All animals successfully underwent the surgical procedure and survived until study termination without any complications. The amount of bleeding from coronary arteriotomy was significantly higher before intracoronary injection of the polymer (5.25 ± 1.65 mL/min versus 0.54 ± 0.53 mL/min, P = 0.0004). Angiography demonstrated that the graft was patent, and there was no evidence of intraluminal foreign bodies. Myocardial samples from the subtended bed showed no evidence of intraarterial polymer or myonecrosis.

Conclusions

Poloxamer 407 reverse-thermal polymer may be a valuable tool in performing coronary anastomoses off-pump. Completion angiograms showed total dissolution of the material with no residual intraarterial polymer visible on tissue samples.

Robotically assisted totally endoscopic coronary artery bypass surgery

Robotically assisted totally endoscopic coronary artery bypass surgery has emerged as a feasible and efficient alternative to conventional full sternotomy coronary artery bypass graft surgery in selected patients. This minimally invasive approach using the daVinci robotic system allows fine intrathoracic maneuvers and excellent view of the coronary arteries. Both on-pump and off-pump operations can be performed to treat single and multivessel disease. Hybrid approaches have the potential of offering complete revascularization with the "best of both worlds" from surgery (internal mammary artery anastomosis in less invasive fashion) and percutaneous coronary intervention (least invasive approach). In this article we review the indications, techniques, short and long term results, as well as current developments in totally endoscopic robotic coronary artery bypass operations.

Anastomotic devices for coronary artery bypass grafting

With the advent of off-pump and minimally invasive coronary artery bypass grafting, efforts to facilitate construction of the graft to coronary anastomosis have increased. As a result, a number of anastomotic devices have been developed. While the ideal anastomotic device should be easy to use, produce a geometrically optimal anastomosis with minimal endothelial damage and minimal blood-exposed nonintimal surface, a number of design constraints apply. This review collects the available preclinical and clinical data for some of the devices, with special regard as to surgical outcome, patency rate and the need for additional perioperative anticoagulation treatment.

Total Endoscopic Beating-Heart Coronary Artery Bypass Grafting Using A New 3D Imaging System

OBJECTIVE

: Since 1999, the authors of this study have performed total endoscopic beating-heart coronary artery bypass. They have developed a new three-dimensional (3D) endoscopic imaging system and have used it successfully in three patients.

METHODS

: From January 2004, a new 3D endoscopic imaging system was used. This device, composed of an optical high-resolution, 3D endoscope and two liquid crystal monitors, gives bright, natural, 3D imaging and enables quick, precise manipulation. After the 15-mm port for the 3D endoscope was inserted through fourth intercostal space (ICS) in the posterior axillary line, the left internal thoracic artery (LITA) was taken down endoscopically in semiskeletonized fashion, using two instrumental 5-mm ports (third and sixth anterior axillary ICS). The pericardium was then opened, and the left anterior descending artery was identified. Another 10-mm port for an endoscopic needle holder was inserted through fourth ICS in the midclavicular line. Three ports were placed in the fourth ICS in line for the anastomosis. An original suction stabilizer was inserted through the first instrumental port, and the left anterior descending artery was immobilized. A conventional end-to-side anastomosis was done with 8-0 Prolene running sutures.

RESULTS

: The average LITA harvesting time was significantly shortened from 68 minutes with two-dimensional imaging to 36 minutes with new 3D imaging. The average anastomotic time was shortened from 34 minutes with two-dimensional imaging and 27 minutes with former 3D imaging to 17 minutes with new 3D imaging. There were no complications and no operative deaths.

CONCLUSIONS

: This new 3D endoscopic imaging system facilitates quick, precise anastomosis and is a useful device for endoscopic coronary bypass surgery.

Anatomical annotation on vascular structure in volume rendered images

The precise annotation of vascular structure is desired in computer-assisted systems to help surgeons identify each vessel branch. This paper proposes a method that annotates vessels on volume rendered images by rendering their names on them using a two-pass rendering process. In the first rendering pass, vessel surface models are generated using such properties as centerlines, radii, and running directions. Then the vessel names are drawn on the vessel surfaces. Finally, the vessel name images and the corresponding depth buffer are generated by a virtual camera at the viewpoint. In the second rendering pass, volume rendered images are generated by a ray casting volume rendering algorithm that considers the depth buffer generated in the first rendering pass. After the two-pass rendering is finished, an annotated image is generated by blending the volume rendered image with the surface rendered image. To confirm the effectiveness of our proposed method, we performed a computer-assisted system for the automated annotation of abdominal arteries. The experimental results show that vessel names can be drawn on the corresponding vessel surface in the volume rendered images at a computing cost that is nearly the same as that by volume rendering only. The proposed method has enormous potential to be adopted to annotate the vessels in the 3D medical images in clinical applications, such as image-guided surgery.

Anesthesia management for robotically assisted endoscopic coronary artery bypass grafting on beating heart

OBJECTIVE

To outline the initial anesthetic experience for robotically assisted coronary artery bypass grafting surgery on beating heart using the da Vinci surgical system.

METHODS

Between February 2007 and September 2009, 76 patients received the surgery with the da Vinci S Surgical System. The crucial issue of anesthesia for the surgery is to deal with the hemodynamic compromise, hypoxia and hypercarbia relevant to one-lung ventilation (OLV), and intrathoracic insufflation of CO2 with positive pressure (CO2 pneumothorax).

RESULTS

After initiation of OLV and CO2 pneumothorax, PaO2 and mixed venous saturation showed a significant decrease. Meanwhile, the SpO2 decreased to 92% in 14 of the 76 patients. In these patients, application of continuous positive airway pressure setting 5 to 15 cm H2O to the collapsed lung resulted in an increase in PaO2 from 59 ± 12 to 115 ± 23 mm Hg (P < 0.05). Moreover, at the beginning of CO2 pneumothorax, the most dramatic fall in mean arterial pressure and cardiac index was showed with an increase in mean pulmonary artery pressure and heart rate. The hemodynamic compromise was counteracted by transfusion and inotropes/vasopressors. Postoperatively, the average extubation time was 7.5 ± 3.1 hours, and median intensive care unit length of stay was 21 hours. One patient remained in the intensive care unit for 3 days for treatment of a postoperative pneumonia. There were two cases of new onset postoperative atrial fibrillation. All patients were discharged home 4 to 7 days after surgery.

CONCLUSIONS

Anesthetic management for the procedures requires detailed knowledge of OLV and CO2 pneumothorax in addition to expertise required in conventional cardiac surgery.

Early and midterm results of totally endoscopic coronary artery bypass grafting on the beating heart

OBJECTIVE

Despite the early introduction of totally endoscopic coronary artery bypass on the beating heart, only a limited number of cases have been performed. The limiting factor has been the concern about safety and graft patency of the anastomosis. This study describes our experience with totally endoscopic coronary artery bypass on the beating heart with robotic assistance and its early and midterm results.

METHODS

In 365 cases of robotic cardiac operations, 162 patients underwent robotic coronary artery bypass grafting on the beating heart, of whom 60 patients (46 male, 14 female) underwent totally endoscopic coronary artery bypass on the beating heart. The patients' mean age was 56.97 ± 9.7 years (33-77 years). Left internal thoracic artery to left anterior descending anastomosis was performed using the U-Clip device.

RESULTS

We completed 58 totally endoscopic coronary artery bypass procedures, in which 16 patients received hybrid procedures. Two patients had conversions to a minithoracotomy. The average left internal thoracic artery harvesting and anastomosis times were 31.3 ± 10.5 (18∼55) minutes and 11.3 ± 4.7 (5∼21) minutes, respectively. The mean operating room and operation times were 336.1 ± 58.5 (210∼580) minutes and 264.8 ± 65.6 (150∼420) minutes, respectively. The drainage was 164.9 ± 83.2 (70∼450) mL. Before discharge, 50 patients underwent angiography and 8 patients underwent computed tomography angiography, and the study showed that graft patency was 100%. Unexpectedly, the left internal thoracic artery graft developed a collateral branch in 2 patients. After discharge, all patients were followed up by computed tomography angiography. The average follow-up time was 12.67 ± 9.43 (1-40) months. One patient had gastric bleeding after surgery.

CONCLUSIONS

Totally endoscopic coronary artery bypass on the beating heart is a safe procedure in selected patients and produces excellent early and midterm patency of anastomosis.

Robotic coronary artery bypass grafting

Robotically assisted surgery enables coronary surgery to be performed totally or partially endoscopically. Using the Da Vinci robotic technology allows minimally invasive treatments. We report on our experience with coronary artery surgery in our department: patients requiring single or double vessel surgical revascularization were eligible. The procedure was performed without cardiopulmonary bypass on a beating heart. From April 2004 to May 2008, 55 consecutive patients were enrolled in the study, and were operated on by a single surgical team. Operative outcomes included operative time, estimated blood loss, transfusions, ventilation time, intensive care unit (ICU) and hospital length of stay. Average operative time was 270 ± 101 min with an estimated blood loss of 509 ± 328 ml, a postoperative ventilation time of 6 ± 12 h, ICU stay of 52 ± 23 h, and a hospital stay of 7 ± 3 days. Nine patients (16%) were converted to open techniques, and transfusion was required in four patients (7%). Follow-up was complete for all patients up to 1 year. There was one hospital death (1.7%) and two deaths at follow-up. Coronary anastomosis was controlled in 48 patients by either angiogram or computed tomography scan, revealing occlusion or anastomotic stenoses (>50%) in six patients. Overall permeability was 92%. Major adverse events occurred in 12 patients (21%). One-year survival was 96%. Our initial experience with robotically assisted coronary surgery is promising: it avoids sternotomy and with a methodical approach we were able to implement the procedure safely and effectively in our practice, combining minimal mortality with excellent survival.

Robotically-assisted coronary artery bypass grafting

Objectives. Robotic surgery enables to perform coronary surgery totally endoscopically. This report describes our experience using the da Vinci system for coronary artery bypass surgery. Methods. Patients requiring single-or-double vessel revascularization were eligible. The procedure was performed without cardiopulmonary bypass on a beating heart. Results. From April 2004 to May 2008, fifty-six patients were enrolled in the study. Twenty-four patients underwent robotic harvesting of the mammary conduit followed by minimal invasive direct coronary artery bypass (MIDCAB), and twenty-three patients had a totally endoscopic coronary artery bypass (TECAB) grafting. Nine patients (16%) were converted to open techniques. The mean total operating time for TECAB was 372 ± 104 minutes and for MIDCAB was 220 ± 69 minutes. Followup was complete for all patients up to one year. There was one hospital death following MIDCAB and two deaths at follow up. Forty-eight patients had an angiogram or CT scan revealing occlusion or anastomotic stenoses (>50%) in 6 patients. Overall permeability was 92%. Conclusions. Robotic surgery can be performed with promising results.

Beating-heart totally endoscopic coronary artery bypass grafting: report of a case

This case report presents beating-heart totally endoscopic coronary artery bypass grafting (TECAB) for single-vessel coronary artery disease. A 72-year-old man with isolated left anterior descending (LAD) coronary artery disease was considered eligible for TECAB. Left internal thoracic artery (LITA) mobilization and subsequent off-pump revascularization applying the LITA to the LAD in a closed chest environment was performed using the da Vinci surgical system (Intuitive Surgical, Mountain View, CA, USA). The LITA was first harvested completely in a totally skeletonized fashion through three incisions 1-2 cm long in the left thoracic wall. The LAD was immobilized with the aid of a heart stabilizer. The LITA was then anastomosed to the LAD with 10 interrupted sutures of a Nitinol self-closing S15 U-clip device (Medtronic, Minneapolis, MN, USA) on the beating heart without the use of cardiopulmonary bypass. The time acquired to perform anastomosis was 20 min, and the total operative time was 5 h 34 min. The postoperative course was uneventful and the patient was discharged 5 days after the operation. Beating-heart TECAB was successfully performed for this patient with single-vessel LAD disease. This approach may be an evolutionary step toward beating-heart multivessel TECAB.

Advances in paediatric interventional cardiology since 2000

Interventional paediatric and congenital cardiology is expanding at a rapid pace. Validated techniques (such as aortic or pulmonary valve dilatations and occlusion of persistent ductus arteriosus and atrial septal defects) are improving thanks to the use of smaller introducers and sheaths, low-profile balloons and novel devices. Moreover, catheter-based interventions have emerged as an attractive alternative to surgery in other fields: pulmonary valve replacement, balloon and stent implantation for native and recurrent coarctation, and percutaneous closure of ventricular septal defects. On the other hand, percutaneous interventions in the paediatric population may be limited by patient size or the anatomy of the defect. Hybrid approaches involving both cardiac interventionists and surgeons are being developed to overcome these limitations. Based on a better understanding of cardiac development, fetal cardiac interventions are being attempted in order to alter the history of severe obstructive lesions. Finally, some interventional procedures still carry a low success rate-for example, pulmonary vein stenosis, even with the use of conventional stents. Biodegradable stents and devices are being developed and may find an application in this setting as well as in others. The purpose of this review is to highlight the advances in paediatric interventional cardiology since the beginning of the third millennium.

Minimally invasive approaches in orthopaedic surgery

Performing orthopaedic interventions with reduced trauma to soft tissue is considered a way to shorten recovery time and improve surgical outcome. Based on an analysis of causes of invasiveness in orthopaedic surgery, associated fields of development are described that aim at the reduction of invasiveness. The causes in question are the need to have visual contact to the performed surgical action, to guide surgical instruments into the <I>situs</I>, and to introduce devices such as screws, plates, or endoprostheses for implantation. This article focuses in particular on the use of navigation technology as a visualization aid to overcome the first cause of invasiveness. Two pay-offs of this approach are discussed which have so far prevented computer-assisted surgery systems from being used less invasively than conventional instruments. Referencing of the anatomy is required to track the spatial position and orientation of the operated bone. Registration establishes a systematic link between all objects involved. Alternatively, contact-less solutions have been proposed for both actions; however, up to now with only limited success. Current trends in robotically supported surgery seem to indicate that this technology may play a more important role in minimally invasive interventions in the future.

Robotics and surgery: a long-term relationship?

This article introduces robotic surgical systems by explaining the shortcomings of traditional laparoscopic surgery, and how these new systems have been developed to address them. This is followed by a descriptive section of robotic systems past and present and their use in different surgical specialities. Finally, we discuss advances that are planned for the development of current systems and the future role of robotics in surgery.

Recent advances in minimal-access cardiac surgery using robotic-enhanced surgical systems

Recent advances in interventional cardiology and cardiac surgery have changed traditional therapeutic algorithms by altering indications, timing and patterns of referral for subsequent surgical treatment. Developments in coronary revascularization have focused on reducing both surgical invasiveness and trauma. Patients with significant comorbid pathologies, those undergoing reinterventions and especially the elderly may benefit from such hybrid procedures by avoiding cardiopulmonary bypass and a midline sternotomy. Minimally invasive techniques have revolutionized cardiothoracic surgery by increasing patient satisfaction and by reducing surgical trauma, hospital stay, and consequently overall costs. There are, however, limitations, but robot-assisted surgery endeavors to minimize these technical hindrances and thus allow better and more accurate surgical practice whilst minimizing surgical trauma.

Feasibility, safety, and efficacy of totally endoscopic coronary artery bypass grafting: multicenter European experience

OBJECTIVE

The invention of robotic systems has begun a new era of endoscopic cardiac surgery. Reports on totally endoscopic coronary artery bypass grafting are limited, however, and data regarding feasibility, safety, and efficacy are needed to determine this technique's position in the therapeutic armamentarium. This study describes the largest multicenter experience in the literature with robotic totally endoscopic coronary artery bypass grafting specifically addressing procedural feasibility, safety, and efficacy.

METHODS

Between September 1998 and November 2002, a total of 228 patients with coronary artery disease were scheduled for totally endoscopic coronary artery bypass grafting with the da Vinci Surgical System (Intuitive Surgical Inc, Sunnyvale, Calif.) at five European institutions. Patients underwent totally endoscopic coronary artery bypass grafting with either an on-pump (group A, n = 117) or an off-pump approach (group B, n = 111). Patients underwent postoperative angiography or stress electrocardiography and were followed up for 6 months.

RESULTS

Procedural feasibility was demonstrated through the completion of 164 successful totally endoscopic cases. Sixty-four patients (group C, 28%) had conversion to nonrobotic procedures. Conversion rates decreased with time. The overall procedural efficacy, as defined by angiographic patency or lack of ischemic signs on stress electrocardiography, was 97%. The incidence of major adverse cardiac events within 6 months was 5%.

CONCLUSION

Both on- and off-pump totally endoscopic coronary artery bypass grafting are feasible, with a conversion rate that diminishes with increasing experience. Conversion does not adversely affect outcome and thus constitutes a safe alternative. Although target vessel reintervention may be slightly higher than that reported for open coronary artery bypass grafting, graft patency and major adverse cardiac events for both approaches are comparable to those reported in the Society of Thoracic Surgeons database, demonstrating the safety and efficacy of the totally endoscopic coronary artery bypass grafting procedure.

Cardiac robotics: a review and St. Mary's experience

BACKGROUND

The introduction of the laparoscope led to the progress of surgery to a new era, where surgeries that were deemed major are now being performed through keyhole incisions with comparable outcomes to open surgery. However, with this new technique rose several problems like inaccurate depth perception, diminished tactile feedback, need for experienced assistance, and reduction in degrees of motion of the surgeons hands all of which inspired surgeons and engineers to look for mechanical tools to help in reducing these problems. Henceforth; came the application of robotics in surgery.

METHODS

A PubMed and Medline search was performed on cardiac robotic surgery and its applications in mitral valve repair and coronary artery surgery. A total of twenty one articles were picked that allude to the subject. A history of robotic surgery was outlined followed by applications of robotic manipulation in cardiac surgery was narrated. A quick overview of this technology in telemedicine was then outlined followed by future prospects of this technology in surgery was contemplated.

RESULTS

The experience of the group from St. Mary's Hospital, London in this field was outlined. During the period of 4 years a total of 102 cases of robotic cardiac surgery were performed. The mean length of hospital stay was 3.1 days with a standard deviation of 1.4 days and the morbidity of the series explained. There was no mortality.

CONCLUSION

Early studies have shown that minimally invasive cardiac surgery is feasible and yields results similar to conventional cardiac surgery, yet it is more technically demanding on the surgeon. As advantageous as this new modality is, further multicenter studies are needed to prove its efficacy.

Totally endoscopic sequential arterial coronary artery bypass grafting on the beating heart

A 50-year-old man was referred to the Department of Thoracic and Cardiovascular Surgery at the Johann Wolfgang-Goethe University (Frankfurt, Germany) with angina on exertion. An evaluation revealed critical stenosis involving the proximal portion of the left anterior descending artery and the first diagonal branch. The patient underwent successful sequential grafting of the left internal mammary artery to the left anterior descending artery and the diagonal branch using a totally endoscopic coronary artery bypass grafting technique on the beating heart with a new version of the da Vinci Surgical System (Intuitive Surgical, USA). To the authors' knowledge, this is the first report in literature to describe sequential arterial off-pump grafting of two anterior wall target vessels using a totally endoscopic technique on the beating heart.

Cost effectiveness analysis of minimally invasive internal thoracic artery bypass versus percutaneous revascularisation for isolated lesions of the left anterior descending artery

OBJECTIVE

To compare the cost effectiveness of percutaneous transluminal coronary artery stenting with minimally invasive internal thoracic artery bypass for isolated lesions of the left anterior descending artery.

DESIGN

Cost effectiveness analysis.

DATA SOURCES

Embase, Medline, Cochrane, Google Scholar, and Health Technology Assessment databases (1966-2005), and reference sources for utility values and economical variables.

METHODS

Decision analytical modelling and Markov simulation were used to model medium and long term costs, quality of life, and cost effectiveness after either intervention using data from referenced sources. Probabilistic sensitivity and alternative analyses were used to investigate the effect of uncertainty about the value of model variables and model structure.

RESULTS

Stenting was the dominant strategy in the first two years, being both more effective and less costly than bypass surgery. In the third year bypass surgery still remained more expensive but became marginally more effective. As the incremental cost effectiveness was 1,108,130.40 pounds sterling (1 682,146.00 euros; $2,179,194) per quality adjusted life year (QALY), the additional effectiveness could not be said to justify the additional cost at this stage. By five years, however, the incremental cost effectiveness ratio of 28,042.95 pounds sterling per QALY began to compare favourably with other interventions. At 10 years the additional effectiveness of 0.132 QALYs (range -0.166 to 0.430) probably justified the additional cost of 829.02 pounds sterling (range 205.56 pounds sterling to 1452.48 pounds sterling), with an incremental cost effectiveness of 6274.02 pounds sterling per QALY. Sensitivity and alternative analysis showed the results were sensitive to the time horizon and stent type.

CONCLUSIONS

Minimally invasive left internal thoracic artery bypass may be a more cost effective medium and long term alternative to percutaneous transluminal coronary artery stenting.

New instrument for robotic-enhanced skeletonized internal thoracic artery harvesting: triangular hook

OBJECTIVE

: The introduction of robotic surgery has generated innovations in minimally invasive coronary surgery, including instrumentation. We have developed a small instrument, named by us the Triangular Hook, that expedites robotic skeletonization of the internal thoracic artery and makes the procedure safer.

METHODS

: Bilateral skeletonized internal thoracic artery harvesting was performed in four dogs (weight, 22 to 36 kg), using the da Vinci surgical system (Intuitive Surgical, Inc, Sunnyvale, CA). One internal thoracic artery was harvested with the Triangular Hook; the other was harvested without it. Harvesting time was measured for each form of harvesting, with the data being reported as mean ± SD.

RESULTS

: All eight internal thoracic arteries were harvested successfully; they were patent at the end of harvesting. Significantly less time was required for the Triangular Hook (41.5 ± 2.8 minutes) than for harvesting without it (47.5 ± 3.9 minutes; P = 0.02).

CONCLUSIONS

: The Triangular Hook is practicable and safe in robotic skeletonization of the internal thoracic artery.

Robotically assisted totally endoscopic atrial septal defect repair: insights from operative times, learning curves, and clinical outcome

BACKGROUND

Remote access perfusion and robotics have enabled totally endoscopic closure of atrial septal defect and patent foramen ovale. The aim of this study was to address learning curve issues of totally endoscopic atrial septal defect repair on the basis of a single-center experience and to investigate whether long cardiopulmonary bypass and aortic occlusion times influence intraoperative and postoperative outcomes.

METHODS

Seventeen patients (median age, 35 years; range, 16 to 55 years) underwent totally endoscopic atrial septal defect repair using remote access perfusion and robotic technology (da Vinci telemanipulation system). Learning curves were assessed by means of regression analysis with logarithmic curve fit. The effect of operative variables on clinical outcome was analyzed by linear regression using the Spearman's rho coefficient.

RESULTS

No operative mortality or serious surgical complications were observed. No residual shunt was detected at intraoperative or postoperative echocardiography. Significant learning curves were noted for total operative time: y(min) = 406 - 49 ln(x) (r2 = 0.725; p = 0.002); cardiopulmonary bypass time: y(min) = 225 - 42 ln(x) (r2 = 0.699; p = 0.003); and aortic occlusion time: y(min) = 117 - 25 ln(x) (r2 = 0.517; p = 0.04), x = number of procedures. Median ventilation time, intensive care unit stay, and hospital length of stay were 7 hours (range, 2 to 19 hours), 26 hours (range, 15 to 120 hours), and 8 days (range, 5 to 14 days), respectively. No correlation was detected between cardiopulmonary bypass time and intubation time (r2 = 0.283; p = 0.326), intensive care unit stay (r2 = -0.138; p = 0.639), or total length of stay (r2 = 0.013; p = 0.962).

CONCLUSIONS

Totally endoscopic atrial septal defect repair can be performed safely, and learning curves for operative times are steep. Longer cardiopulmonary bypass times had no negative impact on intraoperative and postoperative outcome.

[Da Vinci advanced robotic laparoscopic surgery: origin and current clinical application in urology, and comparison with open and laparoscopic surgery]

Over the last decade, open surgery, which is able to perform large extirpations and repairs of fragile tissues, is gradually being substituted with laparoscopic surgery due to the high benefits the latter entails for the patients, an also due to the learning difficulties for surgeons who must make up for such deficiencies applying higher efforts and a larger amount of stress. Robotic surgery stands in for the limitations of conventional laparoscopic surgery by means of performing more ergonomic and more accurate surgeries, particularly in the case of the most complex and difficult to access operations, such as radical prostatectomy. This review will perform a reminder of the history and clinical applications of new advanced and robotic technologies, and also a comparison with open surgery and conventional laparoscopy.

Clinical characteristics of remote Zeus robot-assisted laparoscopic cholecystectomy: A report of 40 cases

AIM: To summarize the performing essentials and analyze the characteristics of remote Zeus robot-assisted laparoscopic cholecystectomy.

METHODS: Robot-assisted laparoscopic cholecystectomy was performed in 40 patients between May 2004 and July 2005. The operating procedures and a variety of clinical parameters were recorded and analyzed.

RESULTS: Forty laparoscopic cholecystectomy procedures were successfully completed with Zeus robotic system. And there were no post-operative complications. Total operating time, system setup time and performing time were 100.3 ± 18.5 min, 27.7 ± 8.8 min and 65.6 ± 18.3 min, respectively. The blood loss and post-operative hospital stay were 30.6 ± 10.2 mL and 2.8 ± 0.8 d, respectively. Camera clearing times and time used for operative field adjustment were 1.1 ± 1.0 min and 2.0 ± 0.8 min, respectively. The operative error was 7.5%.

CONCLUSION: Robot-assisted laparoscopic cholecystectomy following the principles of laparoscopic operation has specific performing essentials. It preserves the benefits of minimally invasive surgery and offers enhanced ability of controlling operation field, precise and stable operative manipulations.

Influence of anastomotic techniques in totally endoscopic coronary artery bypass

BACKGROUND

Beating heart totally endoscopic coronary artery bypass grafting (TECAB) utilizing a computer-enhanced telemanipulation system is a technically challenging procedure. The objective of our study was to compare two different anastomotic techniques.

METHODS

Ten canine beating heart TECAB procedures were performed using Intuitive's daVinci surgical system. Left internal mammary artery (LIMA) to left anterior descending coronary artery (LAD) anastomosis was performed on all subjects. Anastomosis varied between a conventional running suture (8-0 Gore-tex) (group I) and an interrupted nitinol u-clip anastomosis (group II). On-table angiography was then performed to assess graft patency.

RESULTS

While internal mammary artery (IMA) mobilization time decreased over the course of the study (p = 0.017), there was no significant difference in ischaemia time, anastomosis time or angiographic assessment between anastomotic techniques. Although operative time in group II was significantly shorter than in group I, this was likely due to the small sample size. There were no differences in anastomotic time or coronary occlusion time. There were also no significant differences in canine weight, IMA mobilization time, lipectomy/pericardiotomy, LAD identification, subxiphoid port placement, stabilizer position, or LAD dissection time between the cases performed with the conventional running suture and the cases performed with u-clips.

CONCLUSION

Interrupted nitinol clip anastomosis or conventional running suture anastomoses are equally favourable in the short term when performing a TECAB procedure.

Does Preoperative Multislice Computed Tomography Predict Operative Times in Total Endoscopic Coronary Artery Bypass Grafting?

OBJECTIVE

Multislice computed tomography (MSCT) is currently discussed as a potential tool for procedure planning in endoscopic heart surgery. We aimed to assess the influence of various thoracic measurements on operative times in arrested heart totally endoscopic coronary artery bypass grafting (AHTECAB).

METHODS

34 patients (aged 59 years, 71% male) scheduled for AHTECAB were examined prospectively with ECG-gated 16-channel MSCT angiography of coronary arteries and internal mammary arteries. All AHTECABs were single LIMA to LAD bypass operations using the Da Vinci telemanipulator and the ESTECH remote access perfusion system.

RESULTS

The LIMA-LAD distances were: I (at origin of the first diagonal branch) 4.3 cm (2.5-6.0), II (aortic valve level) 3.7 cm (1.1-6.4), III (mitral valve level) 2.9 cm (0.7-5.0), and IV (basis cordis) 2.3 cm (0.6-4.3). The anterioposterior thoracic diameter was 12.4 cm (8.9-15.6), and the transverse diameter was 24.9 cm (21.1-26.8). LIMA-LAD distances I (P = .025, r = .396) and III (P = .042, r = .356) significantly correlated with the anastomotic time. Increased rotation of the heart to the left was associated with a decreased cardiopulmonary bypass time (p = .016, r = -.451).

CONCLUSION

These data suggest that MSCT has the potential to predict operative times in robotic AHTECAB.

Total Endoscopic CABG Using Robotics on Beating Heart

BACKGROUND

The implementation of a total endoscopic coronary surgery on the beating heart with the aid of the Da Vinci surgical system (Intuitive, Sunnyvale, CA) requires a stepwise learning process. After cadaveric training and clinical start of the program in November 2002, we gained experience with arrested heart procedures starting in May 2003. In November 2003, we moved to beating heart surgery.

METHODS

From November 2003 to January 2005, 14 patients with coronary artery disease (mean age of 62 +/- 5 years, female to male ratio 2:12) were operated with the intention to perform a beating heart TECAB (totally endoscopic coronary artery bypass grafting) procedure.

RESULTS

Total conversion rate was 35% (5/14), due to pleural adhesions in 2 patients, injury of the lung during port placement, inability to occlude the LAD with saddle loops, atherosclerotic diseased mammary artery in 1 patient each. Mean operating time was 298 +/- 110 minutes with a steady decline throughout the study period (first 5 patients: 342 +/- 61 minutes, patients 6 to 9: 337 +/- 87 minutes, last 4 patients: 290 +/- 53 minutes), resulting in a 60 minute shorter operating time. Mean ICU stay was 1.3 days and hospital stay lasted on average 8.4 +/- 2.8 days.

CONCLUSION

Total endoscopic bypass surgery on the beating heart with the Da Vinci surgical system can be safely implemented in clinical use. The learning curve results in a constantly decreasing procedure time due to a more effective table team-console surgeon-robotic system interaction and a moderate conversion rate.

Minimal access coronary revascularisation without cardiopulmonary bypass—the impact of robotic technology in the current clinical practice

Recent advances in interventional cardiology and cardiac surgery have changed the traditional therapeutic algorithms by altering indications, timing and patterns of referral for subsequent surgical treatment. The traditional longitudinal sternomy incision has been the surgical approach of choice for multi-vessel coronary revascularisation. Drawbacks of this incision include potential postoperative morbidity, which translates to a prolonged postoperative length of stay. The combination of minimally invasive direct coronary artery bypass (MIDCAB) with percutaneous transluminal coronary angioplasty (PTCA) or stenting (a hybrid approach) is an alternative therapeutic method for patients with multivessel coronary artery disease. Recent advances in percutaneous interventions have attempted to address the problem of re-stenosis, initially through the deployment of bare metal intra-coronary stents and, more recently, with drug-eluting stents. Developments in coronary revascularisation have focused on reducing both surgical invasiveness and trauma. Patients with significant co-morbid pathologies, the ones undergoing re-interventions, and especially the elderly may benefit from such hybrid procedures by avoiding cardiopulmonary bypass and midline sternotomy. Minimally invasive techniques have revolutionized cardiothoracic surgery by increasing patient satisfaction and by reducing surgical trauma, hospital stay and consequently overall costs. There are however limitations. Robot assisted surgery endeavours to minimise these technical hindrances and so allow better and more accurate surgical practice whilst minimising surgical trauma.

Totally endoscopic coronary artery bypass graft: initial experience with an additional instrument arm and an advanced camera system

BACKGROUND

Robotically enhanced telemanipulation for totally endoscopic coronary artery bypass does not provide adequate tactile feedback, traction, or countertraction. The exposition of coronary target sites is difficult, the visual field is limited, and the epicardial stabilization may be troublesome. A fourth robotic arm for endothoracic instrumentation has been added to the da Vinci surgical system to facilitate totally endoscopic operations. The stereoendoscope was upgraded with a wide-angle feature.

METHODS

The procedure was performed in five patients. Four of these patients had left internal thoracic artery (LITA) to left anterior descending artery (LAD) grafting on the beating heart and the fifth had sequential bypass grafting (LITA to diagonal branch and LAD) on an arrested heart. The additional effector arm of the da Vinci surgical system was brought into the operative field beneath the operating table and used as a second right arm. The wide-angle view was activated by either the console or the patient side surgeon.

RESULTS

The mean operative, port placement, and anastomotic times for a beating-heart totally endoscopic coronary artery bypass were 195 +/- 58, 25 +/- 10, and 18 +/- 5 min, respectively. All procedures were free of morbidity and mortality, with satisfactory angiographic control. The sequential arterial bypass grafting procedure was fully completed in totally endoscopic technique.

CONCLUSIONS

The additional instrumentation arm and wide-angle visualization are useful technical improvements of the da Vinci surgical system, solving the problem of traction, countertraction, and facilitated exposition of target sites as well as visualization of the surgical field. They provide potential for wider acceptance of totally endoscopic coronary artery bypass grafting in a larger surgical community.

Current status of robotically assisted coronary revascularization

This article reviews the current status of totally endoscopic coronary revascularization using telemanipulation systems for robotic assistance. Current challenges in implementing a robotic surgical program are discussed, and application of the technology in both arrested and beating heart procedures is considered.

Chronic ultrastructural effects of temporary intraluminal shunts in a porcine off-pump model

BACKGROUND

Temporary intraluminal shunts (TILS) are routinely used in off-pump revascularization to facilitate the anastomosis while maintaining myocardial blood supply. Whereas tourniquet-occlusion can cause vessel wall trauma, potentially adverse chronic effects of TILS on the coronary intima have not been evaluated yet. This chronic large animal study investigated ultrastructural effects of TILS on the vessel wall.

METHODS

Four groups of acute and chronic pigs with either tourniquet-occlusion (TOUR) or TILS (40 kg; acute, n = 12; chronic, n = 20) were analyzed. Animals underwent median sternotomy, heparin (150 U/kg) administration, and left anterior descending coronary artery exposure. In groups with TOUR the left anterior descending coronary artery was temporarily occluded (10 minutes) with a tourniquet. In groups with TILS a silicone shunt (1.5 mm diameter, 12 mm length) was placed in the left anterior descending coronary artery more than 10 minutes and then removed, and the insertion was repaired. Thirty minutes after reperfusion all acute animals were sacrificed whereas chronic animals were extubated, maintained for 3 months, and then sacrificed. The left anterior descending coronary artery regions of occlusion or placement of the TILS silicone bulbs were examined histopathologically by scanning and transmission electron microscopy by a blinded pathologist.

RESULTS

In both acute and chronic investigations animals in the TILS group exhibited significantly less morphologic damage than animals in the TOUR group. In the acute phase significantly more loss of cell junction (p = 0.037), loss of endothelium (p = 0.032), and intimal edema (p = 0.037) in the TOUR group than in the TILS group was observed. Three months later, characteristic features with a changed pattern were detected: vacuolization of the cell (p = 0.03), loss of cell junction (p = 0.042), and removal of basal membrane (p = 0.046) as well as extensive loss of endothelium (p = 0.003) in the TOUR group compared with the TILS group.

CONCLUSIONS

Intimal lesions occur with both maneuvers early and late. However, animals in the TOUR group exhibited injuries significantly more often and more severely. Therefore, acute and chronic intimal integrity of the coronary vessel may be better preserved using TILS and may thus have a positive impact on the extent of de novo stenosis and long-term prognosis of the revascularized region.

Robotic skeletonizing of the internal thoracic artery: is it safe?

BACKGROUND

The advantages of internal thoracic artery skeletonization include early high blood flow, a longer conduit, and less bleeding than pedicle internal thoracic artery grafts. Longer conduits are needed for complete endoscopic arterial revascularization. Therefore this study was designed to determine the feasibility and safety of internal thoracic artery skeletonization using the da Vinci robotic system (Intuitive Surgical, Sunnyvale, CA).

METHODS

Nine dogs underwent bilateral robotic internal thoracic artery harvesting through three ports placed in the left chest. One internal thoracic artery was harvested as a pedicle in each dog, and the other was skeletonized. Internal thoracic artery blood flow was measured in each graft, and comparative endothelial histologic studies were performed. Data are mean +/- the standard error of the mean.

RESULTS

All 18 internal thoracic arteries were harvested successfully. Skeletonized internal thoracic artery harvests required more time (48.0 minutes +/- 1.8) than pedicle internal thoracic artery harvests (39.0 minutes +/- 1.4; p < 0.05). Internal thoracic artery flows during the final intervals were similar (skeletonized = 30.0 mL/min +/- 2.4 vs pedicle = 31.5 mL/min +/- 1.8; p = 0.9). Free internal thoracic artery bleeding flow was similar in both groups (skeletonized = 162.0 mL/min +/- 3.0 vs pedicle = 189.0 mL/min +/- 2.4; p = 0.4). Histologically, both groups were similar with minimal endothelial damage.

CONCLUSIONS

Robotically skeletonized harvesting is safe, but it requires more time (48.0 minutes +/- 1.8) than pedicle internal thoracic artery harvesting. Despite muted tactile feedback with robotics, neither technique was associated with histologic or functional damage. These encouraging results may represent an advantage for complete arterial revascularization in robotic coronary bypass patients.

Clinical experience with devices for facilitated anastomoses in coronary artery bypass surgery

Recent developments in minimally invasive coronary artery surgery have been driven by the introduction of new technologies which should facilitate precise surgical maneuvers on the beating heart within confined spaces. Such technologies include coronary stabilizer systems, cardiac positioning vacuum-assisted devices, and telemanipulative systems. Despite these developments, standard suturing techniques using running polypropylene material remains a limiting factor in the surgeon's ability to perform complete revascularization with high quality anastomoses through minimal approaches to the chest cavity. Clinical validation of proximal and distal anastomotic devices has the potential to substantially improve and perhaps revolutionize minimally invasive coronary surgery. Ideal characteristics of such devices would include applicability to all conduit types, all coronary sizes, interchangeable proximal/distal sequencing of the anastomosis, and safe bail out for device malfunction. However there is an urgent need to define the performance objectives of such systems as well as the general criteria for proper and comparable evaluation and validation of different systems in animal models and subsequently in controlled prospective clinical studies. This review summarizes the most interesting systems available in both experimental and clinical settings.

Robotic surgery: a current perspective

OBJECTIVE

To review the history, development, and current applications of robotics in surgery.

BACKGROUND

Surgical robotics is a new technology that holds significant promise. Robotic surgery is often heralded as the new revolution, and it is one of the most talked about subjects in surgery today. Up to this point in time, however, the drive to develop and obtain robotic devices has been largely driven by the market. There is no doubt that they will become an important tool in the surgical armamentarium, but the extent of their use is still evolving.

METHODS

A review of the literature was undertaken using Medline. Articles describing the history and development of surgical robots were identified as were articles reporting data on applications.

RESULTS

Several centers are currently using surgical robots and publishing data. Most of these early studies report that robotic surgery is feasible. There is, however, a paucity of data regarding costs and benefits of robotics versus conventional techniques.

CONCLUSIONS

Robotic surgery is still in its infancy and its niche has not yet been well defined. Its current practical uses are mostly confined to smaller surgical procedures.