Minimally invasive coronary artery bypass grafting: is it time for the robot?

Electrocoagulation-free strategy in minimally invasive direct coronary artery bypass with hybrid revascularisation - a case report

BACKGROUND

Hybrid coronary revascularisation benefits patients with multivessel disease, as it amalgamates the minimally invasive direct coronary artery bypass (MIDCAB) procedure and percutaneous coronary intervention (PCI). We present a 63-year-old female with triple-vessel coronary artery disease including marked ostial stenosis of the left main coronary artery, as well as moderate stenosis of the right coronary artery. The risk of death following heart surgery (EuroSCORE II) is 4.27%. The patient exhibited multiple morbidities including chronic obstructive pulmonary disease, renal impairment, extracardiac arteriopathy, and multiple prior gastrointestinal surgeries, as well as a recent episode of paroxysmal atrial fibrillation. A MIDCAB procedure without electrocoagulation was stipulated by the ENT specialist due to the patient's cochlear implant.

CONCLUSION

A successful MIDCAB procedure omitting electrocoagulation was performed for the first time for multivessel coronary disease in a multimorbid patient as part of a hybrid approach.

Long-term survival, cardiovascular, and functional outcomes after minimally invasive coronary artery bypass grafting in 566 patients

OBJECTIVE

Sternotomy has been the gold standard incision for surgical revascularization but may be associated with chronic pain and sternal malunion. Minimally invasive coronary artery bypass grafting allows for complete surgical revascularization through a small thoracotomy in selected patients. There is a paucity of long-term data, particularly functional outcomes, for patients who underwent minimally invasive coronary artery bypass grafting.

METHODS

Patients (N = 566) who underwent minimally invasive coronary artery bypass grafting at a single institution over a 17-year period were prospectively followed. The primary outcome was survival. At late follow-up, patients were contacted for a questionnaire on functional outcomes. Multivariable Cox proportional hazard model identified correlates of the primary outcome.

RESULTS

Clinical follow-up was complete for 100% of patients (mean 7.0 ± 4.4 years); a follow-up questionnaire was also completed for 83.9% (N = 427) of live patients. Fifty percent of patients (N = 283) had undergone multivessel grafting. At 12 years, survival for the entire cohort was 82.2% ± 2.6%. On late follow-up questionnaire, 12 patients (2.8%) had greater than Canadian Cardiovascular Score Class II angina and 19 patients (4.5%) had greater than New York Heart Association Class II symptoms. More than 98% of patients did not have pain related to the incision site. Cox proportional hazards analysis identified older age, peripheral vascular disease, prior myocardial infarction, left ventricular dysfunction, cancer in the past 5 years, intraoperative transfusion, and hybrid revascularization as correlates of mortality during follow-up.

CONCLUSIONS

Minimally invasive coronary artery bypass grafting is a safe and durable alternative to sternotomy coronary artery bypass grafting in selected patients, with excellent short- and long-term outcomes, including for multivessel coronary disease. At long-term follow-up, the proportion of patients with significant symptoms and incisional pain was low.

Current Applications and Future Perspectives of Artificial and Biomimetic Intelligence in Vascular Surgery and Peripheral Artery Disease

Artificial Intelligence (AI) made its first appearance in 1956, and since then it has progressively introduced itself in healthcare systems and patients' information and care. AI functions can be grouped under the following headings: Machine Learning (ML), Deep Learning (DL), Artificial Neural Network (ANN), Convolutional Neural Network (CNN), Computer Vision (CV). Biomimetic intelligence (BI) applies the principles of systems of nature to create biological algorithms, such as genetic and neural network, to be used in different scenarios. Chronic limb-threatening ischemia (CLTI) represents the last stage of peripheral artery disease (PAD) and has increased over recent years, together with the rise in prevalence of diabetes and population ageing. Nowadays, AI and BI grant the possibility of developing new diagnostic and treatment solutions in the vascular field, given the possibility of accessing clinical, biological, and imaging data. By assessing the vascular anatomy in every patient, as well as the burden of atherosclerosis, and classifying the level and degree of disease, sizing and planning the best endovascular treatment, defining the perioperative complications risk, integrating experiences and resources between different specialties, identifying latent PAD, thus offering evidence-based solutions and guiding surgeons in the choice of the best surgical technique, AI and BI challenge the role of the physician's experience in PAD treatment.

Maximizing Minimally Invasive Cardiac Surgery With Enhanced Recovery (ERAS)

We convened a group of cardiac surgeons, intensivists, and anesthesiologists with extensive experience in minimally invasive cardiac surgery (MICS) and perioperative care to identify the essential elements of a MICS program and the relationship with Enhanced Recovery After Surgery (ERAS). The MICS incision should minimize tissue invasion without compromising surgical goals. MICS also requires safe management of hemodynamics and preservation of cardiac function, which we have termed myocardial management. Finally, comprehensive perioperative care through an ERAS program should be provided to allow patients to achieve optimal recovery. Therefore, we propose that MICS requires 3 elements: (1) a less invasive surgical incision (non-full sternotomy), (2) optimized myocardial management, and (3) ERAS. We contend that the full benefit of MICS can be achieved only by also utilizing an ERAS platform.

Minimally Invasive Direct Coronary Artery Bypass Grafting: Sixteen Years of Single-Center Experience

Background: Coronary artery disease is a major cause of death globally. Minimally invasive direct coronary artery bypass (MIDCAB), using a small left anterior thoracotomy, aims to provide a less invasive alternative to traditional procedures, potentially improving patient outcomes with reduced recovery times. Methods: This retrospective, non-randomized study analyzed 310 patients who underwent MIDCAB between July 1999 and April 2022. Data were collected on demographics, clinical characteristics, operative and postoperative outcomes, and follow-up mortality and morbidity. Statistical analysis was conducted using IBM SPSS, with survival curves generated via the Kaplan-Meier method. Results: The cohort had a mean age of 63.3 ± 10.9 years, with 30.6% females. The majority of surgeries were elective (76.1%), with an average operating time of 129.7 ± 35.3 min. The median rate of intraoperative blood transfusions was 0.0 (CI 0.0-2.0) Units. The mean in-hospital stay was 8.7 ± 5.5 days, and the median ICU stay was just one day. Early postoperative complications were minimal, with a 0.64% in-hospital mortality rate. The 6-month and 1-year mortalities were 0.97%, with a 10-year survival rate of 94.3%. There were two cases of perioperative myocardial infarction and no instances of stroke or new onset dialysis. Conclusions: The MIDCAB approach demonstrates significant benefits in terms of patient recovery and long-term outcomes, offering a viable and effective alternative for patients suitable for less invasive procedures. Our results suggest that MIDCAB is a safe option with favorable survival rates, justifying its consideration in high-volume centers focused on minimally invasive techniques.

Perioperative Cardiovascular Risk Assessment and Management in Liver Transplant Recipients: A Review of the Literature Merging Guidelines and Interventions

Liver transplantation (LT) is the second most performed solid organ transplant. Coronary artery disease (CAD) is a critical consideration for LT candidacy, particularly in patients with known CAD or risk factors, including metabolic dysfunction associated with steatotic liver disease. The presence of severe CAD may exclude patients from LT; therefore, precise preoperative evaluation and interventions are necessary to achieve transplant candidacy. Cardiovascular complications represent the earliest nongraft-related cause of death post-transplantation. Timely intervention to reduce cardiovascular events depends on adequate CAD screening. Coronary disease screening in end-stage liver disease is challenging because standard noninvasive CAD screening tests have low sensitivity due to hyperdynamic state and vasodilatation. As a result, there is overuse of invasive coronary angiography to exclude severe CAD. Coronary artery calcium scoring using a computed tomography scan is a tool for the prediction of cardiovascular events, and can be used to achieve risk stratification in LT candidates. Recent literature shows that qualitative assessment on both noncontrast- and contrast-enhanced chest computed tomography can be used instead of calcium score to assess the presence of coronary calcium. With increasing prevalence, protocols to address CAD in LT candidates must be reconsidered. Percutaneous coronary intervention could allow a shorter duration of dual-antiplatelet therapy in simple lesions, with safer perioperative outcomes. Hybrid coronary revascularization is an option for high-risk LT candidates with multivessel disease nonamenable to percutaneous coronary intervention. The objective of this review is to evaluate existing methods for preoperative cardiovascular risk stratification, and to describe interventions before surgery to optimize patient outcomes and reduce cardiovascular event risk.

Designing the coronary artery bypass surgery operation of the future

PURPOSE OF REVIEW

This article discusses current shortcomings in coronary artery bypass surgery and ways to overcome them.

RECENT FINDINGS

Minimally invasive coronary bypass surgery, robotic coronary bypass, and hybrid approaches aim to avoid sternotomy, employ arterial grafts, and minimize the use of cardiopulmonary bypass. Other considerations such as bypass graft validation, the optimization of guideline-directed medical therapy, and the development of coronary surgery specialists are also crucial to further the benefits of coronary artery bypass grafting on future patients.

SUMMARY

Coronary artery bypass grafting must become less invasive, be better validated, and be carried out with an even higher emphasis on quality, including graft validation and preoperative/postoperative optimization, if it is to remain the best treatment for advanced, severe coronary artery disease.

Postoperative results of minimally invasive direct coronary artery bypass procedure in 234 patients

Introduction

Minimally invasive approach in cardiac surgery has gained popularity. In order to reduce surgical trauma in coronary surgery minimally invasive direct coronary artery bypass (MIDCAB) has already been established. This technique has been introduced for revascularisation of isolated left anterior descending (LAD). It can also be performed for hybrid revascularisation procedure in multi-vessel disease.

Methods

From 2017 to 2021, 234 patients received MIDCAB operation in our heartcenter 73% were male. Most of the patients had two or three vessel disease (74%). The average age of the patients was 66 ± 12 years mean. The left internal mammary artery (LIMA) was anastomosed to the LAD through left minithoracotomy approach. Multi-vessel MIDCAB (MV-MIDCAB) including two anastomoses (T-graft to LIMA with additional saphenous vein graft) was done in 15% (n = 35).

Results

The average operation time was 2.3 ± 0.8 h mean. The 30-day mortality was 1.7% (n = 4). The average amount of packed red blood cells (pRBC) that was given intra- and postoperatively was 0.4 ± 0.8 units mean. The mean intensive care unit stay (ICU) was 1 ± 1.2 days. Three patients (1.3%) had wound infection postoperatively. The rate of neurologic complications was 0.4% (n = 1). Two patients (0.9%) had myocardial infarction and received coronary re-angiography perioperatively including stent implantation of the right coronary artery.

Discussion

The MIDCAB procedure is a safe and less traumatic procedure for selected patients with proximal LAD lesions. It is also an option for hybrid procedure in multi-vessel disease. The ICU stay and application of pRBC's are low. Our MIDCAB results show a good postoperative clinical outcome. However, follow-up data are necessary to evaluate long-term outcome.

Unilateral left-sided thoracoscopic ablation of atrial fibrillation concomitant to minimally invasive bypass grafting of the left anterior descending artery

OBJECTIVES

Thoracoscopic ablation for atrial fibrillation (AF) and minimally invasive direct coronary artery bypass (MIDCAB) with robot-assisted left internal mammary artery (LIMA) harvesting may represent a safe and effective alternative to more invasive surgical approaches via sternotomy. The aim of our study was to describe the feasibility, safety and efficacy of a unilateral left-sided thoracoscopic AF ablation and concomitant MIDCAB surgery.

METHODS

Retrospective analysis of a prospectively gathered cohort was performed of all consecutive patients with AF and at least a critical left anterior descending artery (LAD) stenosis that underwent unilateral left-sided thoracoscopic AF ablation and concomitant off-pump MIDCAB surgery in the Maastricht University Medical Centre between 2017 and 2021.

RESULTS

Twenty-three patients were included [age 69 years (standard deviation = 8), paroxysmal AF 61%, left atrial volume index 42 ml/m2 (standard deviation = 11)]. Unilateral left-sided thoracoscopic isolation of the left (n = 23) and right (n = 22) pulmonary veins and box (n = 21) by radiofrequency ablation was succeeded by epicardial validation of exit- and entrance block (n = 22). All patients received robot-assisted LIMA harvesting and off-pump LIMA-LAD anastomosis through a left mini-thoracotomy. The perioperative complications consisted of one bleeding of the thoracotomy wound and one aborted myocardial infarction not requiring intervention. The mean duration of hospital stay was 6 days (standard deviation = 2). After discharge, cardiac hospital readmission occurred in 4 patients (AF n = 1; pleural- and pericardial effusion n = 2, myocardial infarction requiring the percutaneous intervention of the LIMA-LAD n = 1) within 1 year. After 12 months, 17/21 (81%) patients were in sinus rhythm when allowing anti-arrhythmic drugs. Finally, the left atrial ejection fraction improved postoperatively [26% (standard deviation = 11) to 38% (standard deviation = 7), P = 0.01].

CONCLUSIONS

In this initial feasibility and early safety study, unilateral left-sided thoracoscopic AF ablation and concomitant MIDCAB for LIMA-LAD grafting is a feasible, safe and efficacious for patients with AF and a critical LAD stenosis.

Minimally Invasive Coronary Revascularisation Surgery: A Focused Review of the Available Literature

Minimally invasive coronary revascularisation was originally developed in the mid 1990s as minimally invasive direct coronary artery bypass (MIDCAB) grafting is a less invasive approach compared to conventional coronary artery bypass grafting (CABG) to address targets in the left anterior descending coronary artery (LAD). Since then, MIDCAB has evolved with the adoption of a robotic platform and the possibility to perform multivessel bypass procedures. Minimally invasive coronary revascularisation surgery also allows for a combination between the benefits of CABG and percutaneous coronary interventions for non-LAD lesions – a hybrid approach. Hybrid coronary revascularisation results in fewer blood transfusions, shorter hospital stay, decreased ventilation times and patients return to work sooner when compared to conventional CABG. This article reviews the available literature, describes standard approaches and considers topics, such as limited access procedures, indications and patient selection, diagnostics and imaging, techniques, anastomotic devices, hybrid coronary revascularisation and outcome analysis.

Review of Contemporary Techniques for Minimally Invasive Coronary Revascularization

Minimally invasive coronary revascularization techniques aim to avoid median sternotomy with its associated complications, while facilitating recovery and maintaining the benefits of surgical revascularization. The 3 most common procedures are minimally invasive coronary artery bypass grafting, totally endoscopic coronary artery bypass, and hybrid coronary revascularization. For a variety of reasons, including cost and technical difficulty, not many centers are routinely performing minimally invasive coronary revascularization. Nevertheless, many studies have assessed the safety and efficacy of each of these procedures in different clinical contexts. Thus far results have been promising, and with the evolution of procedural techniques, these approaches have the potential to redefine coronary revascularization in the future. This review highlights the current state of minimally invasive coronary revascularization techniques by exploring their benefits, identifying barriers to their adoption, and discussing future potential paradigms.

Hiatal hernia after robotic-assisted coronary artery bypass graft surgery

Background

The aim of the present study is to determine the incidence/progression of hiatal hernia (HH) after robotic-assisted coronary artery bypass grafting (RA-CABG) surgery.

Methods

We reviewed the pre- and post-operative computed tomography (CT) of 491 patients who underwent RA-CABG between 2000 and 2017. Post-operative CT was acquired prospectively in a research protocol. CT was reviewed to assess the presence and the size of HH.

Results

We found 444/491 (90.4%) had pre-operative CT, while 201/491 (40.9%) had post-operative CT. In total, 155/491 (31.6%) had both pre- and long-term post-operative CT with a mean follow-up of 6.2 (±3.5) years. HH was more prevalent on post-operative CT, 64/155 (41.3%) compared to pre-operative CT, 44/155 (28.4%), P<0.0001. The diameter of pre-existing HH 2.8 (±1.8) cm was significantly greater after surgery 3.9 (±2.5) cm, P<0.0001. As well the volume of the pre-existing HH 5.8 (4.4-9.2) mL (quartile) was significantly greater after surgery 14.1 (7.2-64.9) mL, P<0.0001. 20/155 (12.9%) had a newly developed HH after RA-CABG. A binary multivariate regression including HH risk factors showed that male gender is a predictor of developing a HH after RA-CABG with Hazard Ratio of 3.038, confidence interval (1.10-8.43), P=0.033.

Conclusions

RA-CABG is associated with an increased risk of developing HH and increases the size of pre-existing HH.

Minimally Invasive coronary surgery compared to STernotomy coronary artery bypass grafting: The MIST trial

RATIONALE

Minimally invasive cardiac surgery has emerged as a safe alternative to standard cardiac surgery. Minimally invasive coronary surgery (MICS CABG) was developed to allow adequate exposure and complete revascularization in CABG from a small thoracotomy incision without cardiopulmonary bypass. Multiple studies have reported significant shorter length of hospital stay and earlier postoperative physical recovery for MICS CABG patients when compared to sternotomy CABG patients. However, there have been no convincing clinical trials that demonstrate improvement in post-operative quality of life for patients who undergo MICS CABG.

STUDY DESIGN

The Minimally Invasive Coronary Surgery compared to Sternotomy Coronary Artery Bypass Grafting (MIST) trial is a multi-centered, prospective randomized controlled trial that compares the quality of life and recovery in the early post-operative period between patients undergoing MICS CABG versus patients undergoing sternotomy CABG. Patients will be randomized either to the MICS CABG group or the sternotomy CABG group, and the target enrollment is 88 patients per group. The primary outcome is quality of life assessment performed by SF-36 questionnaire at 1 month.

CONCLUSION

The MIST trial is the first prospective study that compares the quality of life between MICS CABG and sternotomy CABG patients. The results of this trial may enhance the procedural desirability of MICS CABG by patients and provide an incentive for surgeons and institutions to increase the availability of MICS CABG in suitable patients.

A minimally invasive robotic surgery approach to perform totally endoscopic coronary artery bypass on beating hearts

The currently available robotic systems rely on rigid heart stabilizers to perform totally endoscopic coronary artery bypass (TECAB) surgery on beating hearts. Although such stabilizers facilitate the anastomosis procedure by immobilizing the heart and holding the surgery site steady, they can cause damage to the heart tissue and rupture of the capillary vessels, due to applying relatively large pressures on the epicardium. In this paper, we propose an advanced robotic approach to perform TECAB on a beating heart with minimal invasiveness. The idea comes from the fact that the main pulsations of the heart occur as excursions in normal direction, i.e., perpendicular to the heart surface. We devise a 1-DOF flexible heart stabilizer which eliminates the lateral movements of the heart, and a 1-DOF compensator mechanism which follows the heart trajectory in the normal direction, thus canceling the relative motion between the surgical tool and the heart surface. In fact, we bring a compromise between two radical approaches of operating on a completely immobilized beating heart with no heart motion compensation, and operating on a freely beating heart with full compensation of heart motion, considering the invasiveness of the first and the technical challenges of the second approach. We propose operating on a partially stabilized beating heart with unidirectional compensation of the heart motion; the flexible stabilizer would exert much less holding force to the heart tissue and the robotic system with unidirectional compensator would be technically feasible. In the proposed approach, a motion sensor mounted on the stabilizer measures the heart excursion data and sends it into a control unit. A predictive controller uses this data to generate an automated trajectory. The slave robots follow this trajectory, which is superimposed on the surgeon's tele-operation commands received from a master console. Finally, the tool-activation units in the slave robots actuate the articulated laparoscopic tools to perform the anastomosis procedure. The evaluation of the hypothesis showed that our solution for the robotic TECAB on beating heart is both practical and cost effective. We showed in an in-vivo study that the flexible stabilizer can effectively restrict the heart lateral movements, while allowing for its normal excursion. We found readily available linear motors which could afford the high forces, speeds and accelerations required for following the heart trajectory. Finally, we showed that the tool-activation unit is capable of providing the maneuverability and workspace required for the most challenging task of CABG procedure, i.e., anastomosis suturing.

Assessment of Physical Activity by Wearable Technology During Rehabilitation After Cardiac Surgery: Explorative Prospective Monocentric Observational Cohort Study

Background

Wearable technology is finding its way into clinical practice. Physical activity describes patients’ functional status after cardiac surgery and can be monitored remotely by using dedicated trackers.

Objective

The aim of this study was to compare the progress of physical activity in cardiac rehabilitation by using wearable fitness trackers in patients undergoing coronary artery bypass surgery by either the conventional off-pump coronary artery bypass (OPCAB) or the robotically assisted minimally invasive coronary artery bypass (RA-MIDCAB). We hypothesized faster recovery of physical activity after RA-MIDCAB in the first weeks after discharge as compared to OPCAB.

Methods

Patients undergoing RA-MIDCAB or OPCAB were included in the study. Each patient received a Fitbit Charge HR (Fitbit Inc, San Francisco, CA) physical activity tracker following discharge. Rehabilitation progress was assessed by measuring the number of steps and physical activity level daily. The physical activity level was calculated as energy expenditure divided by the basic metabolic rate.

Results

A total of 10 RA-MIDCAB patients with a median age of 68 (min, 55; max, 83) years and 12 OPCAB patients with a median age of 69 (min, 50; max, 82) years were included. Baseline characteristics were comparable except for body mass index (RA-MIDCAB: 26 kg/m²; min, 22; max, 28 versus OPCAB: 29 kg/m²; min, 27; max, 33; P<.001). Intubation time (P<.05) was significantly lower in the RA-MIDCAB group. A clear trend, although not statistically significant, was observed towards a higher number of steps in RA-MIDCAB patients in the first week following discharge.

Conclusions

RA-MIDCAB patients have an advantage in recovery in the first weeks of revalidation, which is reflected by the number of steps and physical activity level measured by the Fitbit Charge HR, as compared to OPCAB patients. However, unsupervised assessment of daily physical activity varied widely and could have consequences with regard to the use of these trackers as research tools.

Initiation and modification of minimally invasive coronary artery bypass grafting

Minimally invasive coronary artery bypass grafting (MICS CABG) via a small left thoracotomy has been proposed as an alternative to standard coronary artery bypass grafting. However, this technique is still limited to skillful surgeons. Off-pump multi-vessel bypass grafting and the use of bilateral internal thoracic arteries are particularly challenging via a small thoracotomy, while they are widely performed via a full median sternotomy. The purpose of this review is to serve as a guide for the proper introduction of MICS CABG in the current era. We examine the advances, current techniques, outcomes and learning curves of MICS CABG and discuss the safe introduction.

Evolution of Minimally Invasive Coronary Artery Bypass Grafting: Learning Curve

OBJECTIVE

Minimally invasive coronary surgery approach for coronary artery bypass grafting is a safe and reproducible procedure for multivessel revascularization. This study reviewed a single surgeon's experience with minimally invasive coronary surgery coronary artery bypass grafting, including operative time, number of bypasses, and conversion to sternotomy.

METHODS

A prospective database of consecutive minimally invasive coronary surgery coronary artery bypass grafting procedures from 2005 to 2013 was reviewed. A small anterolateral left thoracotomy allowed left internal mammary artery harvest, proximal anastomoses on the ascending aorta, and distal coronary anastomoses. Early cases were compared with the later cases, focusing on grafting strategies that led to a standardized approach with Propensity Score Matching analysis.

RESULTS

Seven hundred consecutive cases were divided into early (1-200) and late (201-700) groups. In the late group, the number of triple-vessel disease patients trended higher (50% vs. 57%, P = 0.0674) and the number of bypasses increased (2.3 ± 0.8 vs. 2.7 ± 1.0, P < 0.0001). Conversion to sternotomy significantly decreased between the groups (6% vs. 0.6%, P < 0.0001). There was no difference in rate of postoperative complications between the groups except for prolonged intubation (10% vs. 5%, P = 0.0236) and shortened length of stay (5.9 ± 6.7 vs. 5.5 ± 6.0, P = 0.0268). Propensity score matching analysis (n = 177) was significant for total bypass performed and time per bypass (P < 0.05). The late group was further divided into subgroups of one hundred each (subgroup 1 through 5). Operative times differed significantly (subgroup 1: 249 ± 71.2, subgroup 2: 259 ± 85.8, subgroup 3: 244 ± 71.0, subgroup 4: 270 ± 58.4, and subgroup 5: 246 ± 47.9, P < 0.005).

CONCLUSIONS

As experience with minimally invasive coronary surgery coronary artery bypass grafting increased, the ideal sequence of steps to optimize surgical outcome was defined. The number of bypassed vessels increased and the operative time and conversion to sternotomy decreased.

Minimally Invasive Cardiovascular Surgery: Incisions and Approaches

Throughout the modern era of cardiac surgery, most operations have been performed via median sternotomy with cardiopulmonary bypass. This paradigm is changing, however, as cardiovascular surgery is increasingly adopting minimally invasive techniques. Advances in patient evaluation, instrumentation, and operative technique have allowed surgeons to perform a wide variety of complex operations through smaller incisions and, in some cases, without cardiopulmonary bypass. With patients desiring less invasive operations and the literature supporting decreased blood loss, shorter hospital length of stay, improved postoperative pain, and better cosmesis, minimally invasive cardiac surgery should be widely practiced. Here, we review the incisions and approaches currently used in minimally invasive cardiovascular surgery.

Minimally invasive coronary artery bypass grafting: a systematic review

To minimize surgical morbidity in coronary artery bypass grafting, minimally invasive cardiac surgery has gained popularity. Minimally invasive coronary artery bypass grafting offers unique advantages compared to conventional off-pump coronary artery bypass or minimally invasive direct coronary artery bypass in that it enables the surgeon to harvest and graft bilateral internal thoracic arteries via a small thoracotomy while being conducted completely off-pump. This review focuses on current evidence behind off-pump coronary artery bypass, multi-arterial revascularization, patient populations that would most benefit from bilateral internal thoracic artery minimally invasive coronary artery bypass grafting, the surgical technique, and early outcomes. By overcoming the perceived inability to utilize bilateral internal thoracic arteries in minimally invasive coronary artery bypass grafting, the new technique further expands the armamentarium of surgeons and cardiologists. Hybrid coronary revascularization with bilateral internal thoracic artery minimally invasive coronary artery bypass grafting further augments the appeal of the next generation of minimally invasive cardiac surgery.

A new forecasting kinematic algorithm of automatic navigation for a laparoscopic minimally invasive surgical robotic system

This paper presents a novel forecasting kinematic algorithm for autonomously navigating the 3D visual window of laparoscopic minimally invasive surgical robotic system (LMISRS). By the application of the proposed technique, a constant distribution area ratio of the micro devices can be guaranteed in the visual window; real-time concurrency motion of the visual window of the laparoscope and the mark points of the instruments is realized, i.e. the visual window can keep tracking the movement of the marks automatically, so that the user does not have to switch between the master-slave controlling targets. The implementation of the new technique is summarized as follows: the robotic kinematics and space analytic geometry are thoroughly analyzed and modeled, and a “following kinematic algorithm” is proposed for the visual window of the laparoscope, which tracks the mark points of the instrument arms; a “forecasting kinematic algorithm” is established by using a combination of the “following kinematic algorithm”, the basic visual parameters of 3D visual field, the Verhulst Grey Model and the filtered amendment method. The proposed technique is verified by a series of simulations by using two groups of marks' motion trails with different sampling times, indicating that the technique is accurate, feasible and robust.

Minimally Invasive Coronary Artery Bypass Grating Using Bilateral In Situ Internal Thoracic Arteries

When performing minimally invasive coronary artery bypass grafting (MICS CABG), it is difficult to access the right internal thoracic artery (ITA) under direct vision. We successfully performed off-pump MICS CABG using the bilateral in situ ITAs through a 8-cm left thoracotomy under direct vision for a 76-year-old man. His postoperative course was uneventful and all the grafts were patent. This novel, minimally invasive approach safely preserves the sternum and delivers the benefits of bilateral in situ ITA grafting, providing an alternative to conventional CABG and off-pump CABG.

Off-Pump Minimally Invasive Coronary Artery Bypass Grafting with a Heart Positioner Direct Retraction for a Better Exposure

Objective

Lateral and inferior territories are difficult to expose during off-pump minimally invasive coronary artery bypass grafting (MICS CABG). The use of cardiopulmonary bypass is required at times. We initiated a direct retraction method by using a cardiac positioner for a better exposure, in order to complete off-pump, multivessel MICS CABG safely.

Methods

We recently initiated multivessel MICS CABG, performed via a 6- to 9-cm left thoracotomy. For distal anastomoses, the lateral pericardial edge was pulled to the chest wall to optimize exposure of the lateral and inferior area. Next, a single- or multisuction cardiac positioner was put on the sides of the target vessel through the small thoracotomy and pulled directly toward the incision. Finally, a distal anastomosis was made with an epicardial stabilizer via the thoracotomy, as in standard off-pump CABG.

Results

There was no mortality or conversion to sternotomy. A total of 10 cases were targeted for off-pump multivessel MICS CABG with this approach. Nine were completed, while 1 still required pump assist. The average number of distal anastomoses was 2.8 ± 0.8. Two were successful off-pump quadruple bypass grafting with sequential anastomoses. All patients were discharged and remain well to this day.

Conclusions

Most multivessel MICS CABG was feasible without pump assist even at the initiation period. This approach is easy and helpful in providing good exposure of target vessels without requirement of additional incisions.