Precision Incision: Robotic Coronary Revascularization via 3.9-cm Minithoracotomy

ABSTRACT: Coronary artery bypass grafting remains the treatment choice for coronary artery disease; but sternotomy, the most commonly used approach, compromises its benefits with postoperative morbidity, higher complication rates, and prolonged length of hospital stay. Despite this, minimally invasive and robotic-assisted technology has not been adopted or widely embraced because supporting literature on robotic-assisted coronary artery bypass grafting is extremely limited. Since 2005, the cardiothoracic surgical team at our institution has been developing and maturing an effective method using robotic harvesting of the left internal mammary artery (LIMA) and beating heart surgery through a minithoracotomy for coronary revascularization. This surgical technique involves precisely placing the robotic endoscopic port immediately over the left anterior descending (LAD) artery target site. The robotically harvested LIMA is secured to the epicardium at the LAD target, the robotic instruments are removed, and the endoscopic port site is enlarged slightly greater than 1 cm to become the minithoracotomy and allow for LIMA-to-LAD anastomosis. The other two robotic ports are used to complete the procedure without a need for additional incisions. This standardized method has been used in more than 750 patients, and since 2009, the last 377 consecutive non-rib-spreading minithoracotomy incisions measured a median of 3.9 cm (mean [SD], 4.16 [1.2748] cm; range, 2.3-12.0 cm). This "How I Do It" article describes our methods in detail and associated robotic nuances.     

Robotically assisted coronary endarterectomy

Robotic assistance has enabled coronary artery bypass surgery to be performed safely in a completely endoscopic fashion, but diffusely diseased target vessels may pose a technical challenge. We present a case in which coronary endarterectomy was performed on the left anterior descending coronary artery during a two-vessel totally endoscopic coronary artery bypass procedure. A 52-year-old woman presented with intermittent substernal pain. Preoperative studies showed diffuse disease in the left coronary artery system. Bilateral internal mammary arteries were harvested robotically using a skeletonized technique in a completely endoscopic fashion. Cardiopulmonary bypass was achieved via peripheral cannulation, and the heart was arrested with intermittent cold antegrade hyperkalemic blood cardioplegia delivered via an ascending aortic occlusion balloon catheter. The first obtuse marginal anastomosis was performed. The left anterior descending coronary artery was diffusely diseased and heavily calcified. An end-to-side anastomosis was attempted to the right internal mammary artery with unsatisfactory results. A localized coronary endarterectomy was performed, and an extended anastomosis was completed using the right internal mammary artery. The patient recovered uneventfully and was discharged home on postoperative day 6. Diffuse coronary artery disease was once thought to be a prohibitive challenge for minimally invasive coronary bypass procedures. This case demonstrates that local coronary endarterectomy is feasible and safe in robotic totally endoscopic coronary artery bypass surgery.     

Arterial end-to-side grafting in coronary artery bypass grafting: the Tector procedure

Background. The current treatment of choice in patients with three-vessel coronary disease is coronary artery bypass grafting. The use of the left internal mammary artery in bypass grafting has shown superior long-term outcomes compared with venous grafting. In our study we assess the safety and feasibility of all-arterial coronary artery bypass graft surgery using the procedure as described by Tector et al. in 2001.Methods. Between June 2001 and February 2007, we studied 133 patients eligible for non-emergency surgical revascularisation. Primary endpoints were death or re-infarction within a 30-day period. Secondary endpoints were the need for emergency coronary surgery, angioplasty and mediastinitis. Long-term follow-up had a mean duration of 33 months postoperatively.Results. All 133 patients were successfully revascularised, 98% with the off-pump technique. In 93% of the patients (n=124) full arterial grafting was achieved using both internal mammary arteries. Thirty-day mortality was 1.5% (n=2), ten re-thoracotomies were performed, one myocardial infarction and one case of mediastinitis were reported. In the next four years six additional patients died. Most of these deaths were due to non-cardiovascular causes. Two patients required angioplasty because of distal bypass graft failure and one for new native coronary artery disease. Conclusion. All-arterial bypass grafting using both internal mammary arteries with the technique as described by Tector is safe and feasible without excess deep sternal wound infections. Late major adverse cardiac events are rare and due to distal graft dysfunction, which can be treated by percutaneous coronary intervention. (Neth Heart J 2010;18:7-11.)     

Telemanipulatory application of a magnetic coupler on the beating heart with the daVinci surgical system]

The construction of a coronary anastomosis on the beating heart under totally endoscopic conditions is technically demanding. In this study the potential benefits of an endoscopic magnetic vascular coupler (MVP, Ventrica, Inc, Fremont, CA) designed to facilitate construction of a coronary anastomosis with the help of the daVinci telemanipulator (Intuitive Surgical Inc., Sunnyvale, CA) were evaluated in a totally endoscopic coronary arterial bypass (TECAB) operation on the beating heart in eight dogs. The telemanipulated instruments were used to guide and place the endoscopic MVP-application platform (prototype). All animals underwent angiography, and gross inspection of the anastomotic site was done after excision of the hearts. The procedure was accomplished in 169 minutes (155-190). With the exception of one premature deployment, all MVP-anastomoses were accomplished in 3 minutes (1-28). The following adverse events were encountered: Bleeding from the right ventricle caused by occlusion tape (1), anastomotic leakage upon reperfusion requiring repair stitches (2), anastomotic occlusion due to a thrombus (1). All but one animal that died on reperfusion despite a patent graft and anastomosis, survived the procedure. Overall patency was 7 out of 8. The combination of telemanipulator technology allowing increased manipulation dexterity in a total endoscopic environment and the effective and time saving magnetic technique for anastomotic coupling has the potential to facilitate TECAB on the beating heart.     

Free radical reaction products and antioxidant capacity in beating heart coronary artery surgery compared to conventional bypass

Oxygen-derived free radicals are important agents of tissue injury during ischemia and reperfusion. The aim of this study was to investigate changes in protein and lipid oxidation and antioxidant status in beating heart coronary artery surgery and conventional bypass and to compare oxidative stress parameters between the two bypass methods. Serum lipid hydroperoxide, nitric oxide, protein carbonyl, nitrotyrosine, vitamin E, and β-carotene levels and total antioxidant capacity were measured in blood of 30 patients undergoing beating heart coronary artery surgery (OPCAB, off-pump coronary artery bypass grafting) and 12 patients undergoing conventional bypass (CABG, on-pump coronary artery bypass grafting). In the OPCAB group, nitric oxide and nitrotyrosine levels decreased after reperfusion. Similarly, β-carotene level and total antioxidant capacity also decreased after anesthesia and reperfusion. In the CABG group, nitric oxide and nitrotyrosine levels decreased after ischemia and reperfusion. However, protein carbonyl levels elevated after ischemia and reperfusion. Vitamin E, β-carotene, and total antioxidant capacity decreased after ischemia and reperfusion. Significantly decreased nitration and impaired antioxidant status were seen after reperfusion in both groups. Moreover, elevated protein carbonyls were found in the CABG group. The off-pump procedure is associated with lower degree of oxidative stress than on-pump coronary surgery.     

Evaluation of a Novel Laser-assisted Coronary Anastomotic Connector - the Trinity Clip - in a Porcine Off-pump Bypass Model

To simplify and facilitate beating heart (i.e., off-pump), minimally invasive coronary artery bypass surgery, a new coronary anastomotic connector, the Trinity Clip, is developed based on the excimer laser-assisted nonocclusive anastomosis technique. The Trinity Clip connector enables simplified, sutureless, and nonocclusive connection of the graft to the coronary artery, and an excimer laser catheter laser-punches the opening of the anastomosis. Consequently, owing to the complete nonocclusive anastomosis construction, coronary conditioning (i.e., occluding or shunting) is not necessary, in contrast to the conventional anastomotic technique, hence simplifying the off-pump bypass procedure. Prior to clinical application in coronary artery bypass grafting, the safety and quality of this novel connector will be evaluated in a long-term experimental porcine off-pump coronary artery bypass (OPCAB) study. In this paper, we describe how to evaluate the coronary anastomosis in the porcine OPCAB model using various techniques to assess its quality. Representative results are summarized and visually demonstrated.     

Capacities of multidetector spiral computed tomography in the planning and postoperative examination of patients undergoing coronary artery bypass surgery

Multiple investigations show that multidetector spiral computed tomography (MSCT) bypass grafting becomes an alternative to invasive coronary angiography in detecting coronary graft stenoses and occlusions. The investigation retrospectively estimated the patency of aortocoronary and mammary coronary artery anastomoses by MSCT bypass grafting. Examinations were made in 85 (326 anastomoses) patients who had undergone aortocoronary and mammary coronary artery bypass surgery and had MSCT bypass grafting within 3 years after the surgery. In the first year following the surgery, 18 patients with graft stenotic changes, as evidenced by MSCT, underwent intervention coronary angiography, the sensitivity and specificity of which was 100%. The results of clinical and instrumental examinations were also compared with graft incompetence, as shown on MSCT that revealed that MSCT bypass grafting was the only noninvasive technique to evaluate early coronary graft closure both in the absence of clear signs of myocardial ischemia according to the data of exercise tests and in the presence of recurrent angina pectoris.     

Endoscopic lesser saphenous vein harvesting for coronary artery bypass grafting: first reported case

Endoscopic vessel harvesting has become a widely used modality for harvesting venous and arterial conduits for coronary artery bypass grafting. Specifically, it has been used to harvest the greater saphenous vein, internal thoracic artery, and the radial artery. A case of endoscopic lesser saphenous vein harvesting for coronary artery bypass grafting is reported.     

Simultaneous off-pump coronary artery bypass grafting and ascending aortobifemoral bypass graft via ventral abdominal route

Aortoiliac disease often coexists with coronary artery disease. It is not uncommon to subject a patient to two separate interventions. We report two cases in which in simultaneous off-pump coronary artery bypass grafting was done with an ascending aortobifemoral bypass graft through the ventral abdominal route without any additional morbidity. Combining a technically simple method of limb bypass with an off-pump cardiac surgery is a promising procedure for revascularization of myocardium and lower limbs. We discuss the merits of combining an off-pump coronary artery bypass grafting procedure with a limb bypass.     

Contemporary use of arterial and venous conduits in coronary artery bypass grafting: anatomical,functional and clinical aspects

Although the benefits of using the left internal mammary artery to bypass the left anterior descending artery (LAD) have been extensively ascertained, freedom from major cardiovascular events and survival after coronary artery bypass grafting (CABG) also correlate with the completeness of revascularisation. Hence, careful selection of the second-best graft conduit is crucial for CABG success. The more widespread use of saphenous vein grafts contrasts with the well-known long-term efficacy of multiple arterial grafting, which struggles to emerge as the procedure of choice due to concerns over increased technical difficulties and higher risk of postoperative complications. Conduit choice is at the discretion of the operator instead of being discussed by the heart team, where cardiologists are not usually engaged in such decisions due to a hypothetical lack of technical knowledge. Furthermore, according to the ESC/EACTS guidelines, traditional CABG remains the gold standard for multi-vessel coronary artery disease with complex LAD stenosis, but hybrid procedures using percutaneous coronary intervention for non-LAD targets could combine the best of two worlds. With the aim of raising the cardiologist’s awareness of the surgical treatment options, we provide a comprehensive overview of the anatomical, functional and clinical aspects guiding the decision-making process in CABG strategy.     

选择性冠状静脉动脉化搭桥术中不同移植物的应用疗效比较

目的:对比选择性冠状静脉动脉化(SCVBG)搭桥治疗弥漫性右冠状动脉狭窄病变中选择乳内动脉和大隐静脉作为桥血管的治疗效果。方法:选择2008年10月到2014年10月在我院行SCVBG搭桥的84例患者资料,其中选择大隐静脉作为桥血管进行冠状静脉动脉化搭桥患者46例(大隐静脉桥组),选择乳内动脉作为桥血管进行冠状静脉动脉化搭桥患者38例(乳内动脉桥组)。随访记录两组患者的生存情况、近期复查超声心动图、冠状动脉CTA及心绞痛复发率。结果:乳内动脉桥组患者总生存率(100%)明显高于大隐静脉桥组(82.6%)(P0.05)。乳内动脉桥组患者桥血管和心中静脉通畅率(100%)明显大于大隐静脉桥组(54.35%)(P0.05)。两组患者左心室射血分数(LVEF)较治疗前明显增加,左心室舒张期末内径(LVEDD)较治疗前明显减小(P0.05)。治疗后,乳内动脉桥组患者心绞痛复发率明显小于大隐静脉桥组(P0.05)。结论:SCVBG搭桥治疗弥漫性右冠状动脉狭窄病变中,选择乳内动脉桥效果优于大隐静脉桥,能明显提高桥血管和心中静脉通畅率,降低心绞痛复发率。     

A Comparison of Genome-Wide DNA Methylation Patterns between Different Vascular Tissues from Patients with Coronary Heart Disease

Epigenetic mechanisms of gene regulation in context of cardiovascular diseases are of considerable interest. So far, our current knowledge of the DNA methylation profiles for atherosclerosis affected and healthy human vascular tissues is still limited. Using the Illumina Infinium Human Methylation27 BeadChip, we performed a genome-wide analysis of DNA methylation in right coronary artery in the area of advanced atherosclerotic plaques, atherosclerotic-resistant internal mammary arteries, and great saphenous veins obtained from same patients with coronary heart disease. The resulting DNA methylation patterns were markedly different between all the vascular tissues. The genes hypomethylated in athero-prone arteries to compare with atherosclerotic-resistant arteries were predominately involved in regulation of inflammation and immune processes, as well as development. The great saphenous veins exhibited an increase of the DNA methylation age in comparison to the internal mammary arteries. Gene ontology analysis for genes harboring hypermethylated CpG-sites in veins revealed the enrichment for biological processes associated with the development. Four CpG-sites located within the MIR10B gene sequence and about 1 kb upstream of the HOXD4 gene were also confirmed as hypomethylated in the independent dataset of the right coronary arteries in the area of advanced atherosclerotic plaques in comparison with the other vascular tissues. The DNA methylation differences observed in vascular tissues of patients with coronary heart disease can provide new insights into the mechanisms underlying the development of pathology and explanation for the difference in graft patency after coronary artery bypass grafting surgery.     

Risk of iron overload is decreased in beating heart coronary artery surgery compared to conventional bypass.

Conventional cardiopulmonary bypass surgery (CCPB) increases the iron loading of plasma transferrin often to a state of plasma iron overload, with the presence of low molecular mass iron. Such iron is a potential risk factor for oxidative stress and microbial virulence. Here we assess 'off-pump' coronary artery surgery on the beating heart for changes in plasma iron chemistry. Seventeen patients undergoing cardiac surgery using the 'Octopus' myocardial wall stabilisation device were monitored at five time points for changes in plasma iron chemistry. This group was further divided into those (n=9) who had one- or two- (n=8) vessel grafts, and compared with eight patients undergoing conventional coronary artery surgery. Patients undergoing beating heart surgery had significantly lower levels of total plasma non-haem iron, and a decreased percentage saturation of their transferrin at all time points compared to conventional bypass patients. Plasma iron overload occurred in only one patient undergoing CCPB. Beating heart surgery appears to decrease red blood cell haemolysis, and tissue damage during the operative procedures and thereby significantly decreases the risk of plasma iron overload associated with conventional bypass.     

Acute repair of a full-thickness right ventricular defect with a composite myofascial pedicle flap.

A full-thickness defect of the right ventricle presented acutely after mediastinitis and sternal dehiscence. This developed 29 days after bilateral internal mammary artery harvest for coronary artery bypass grafting. The defect was managed successfully with a pedicled left rectus abdominis muscle flap using an attached island of the anterior rectus sheath for endocardial lining. The vascular anatomic basis for viability of the rectus abdominis muscle flap after internal mammary artery harvest is derived primarily from musculophrenic, lumbar, lower sixth intercostal, and subcostal artery communications. In addition, the advantages of a myofascial pedicle flap for reconstruction of full-thickness cardiac defects are its ready availability and a strong anterior fascial sheath that can be used as a neoendocardial lining. The patient did well and remains asymptomatic after 3 years.     

Biomechanical rationale of coronary artery bypass grafting of multivessel disease

The biomechanical model of human coronary arteries was modified for improving the quality of diagnosis and surgical treatment for coronary heart disease. The problem of hemodynamics in the left coronary artery with multivessel bed disease – 45% stenosis of the anterior descending branch and 75% stenosis of the circumflex branch – was particularly considered. Numerical simulation of the coronary arterial bypass of the main trunk was carried out to estimate the functional condition of the coronary arteries after restoring myocardial blood supply by surgery.     

The new era of cardiac surgery: hybrid therapy for cardiovascular disease

Surgical therapy for cardiovascular disease carries excellent long-term outcomes but it is relatively invasive. With the development of new devices and techniques, modern cardiovascular surgery is trending toward less invasive approaches, especially for patients at high risk for traditional open heart surgery. A hybrid strategy combines traditional surgical treatments performed in the operating room with treatments traditionally available only in the catheterization laboratory with the goal of offering patients the best available therapy for any set of cardiovascular diseases. Examples of hybrid procedures include hybrid coronary artery bypass grafting, hybrid valve surgery and percutaneous coronary intervention, hybrid endocardial and epicardial atrial fibrillation procedures, and hybrid coronary artery bypass grafting/carotid artery stenting. This multidisciplinary approach requires strong collaboration between cardiac surgeons, vascular surgeons, and interventional cardiologists to obtain optimal patient outcomes.     

Combined surgical approach to carotid and coronary artery disease

The aim of this study was to compare two different surgical approaches to patients with coexistent significant carotid and coronary artery obstruction. Patients were treated with combined operation of carotid endarterectomy and coronary artery bypass grafting (CEA/CABG). The first group of patients underwent the CABG procedure with the cardiopulmonary bypass (CPB) on arrested heart and the second group without the CPB on a beating heart--off pump. Between May 15 1998, and October 9 2003, thirty-five consecutive patients underwent the combined procedure. In both groups there were no cases of transient or permanent perioperative neurological events. Overall, early mortality was 5.6%. The incidence of a perioperative myocardial infarction was 5.5%. In the follow-up period there were no cases of late stroke. According to the presented results in this study, it was found that the combined CEA and CABG is an equally safe and effective procedure performed with or without cardiopulmonary bypass for patients with a severe coexistent carotid and coronary artery disease.     

Right Internal Mammary Artery Implantation into Right Ventricular Myocardium for Revascularization of the Entire Heart: Experimental Data and Preliminary Report

The left internal mammary artery implant combined with epicardiectomy and free omental graft provides three extra-coronary sources of blood. This operation tested in dogs with 92% main-stem occlusion of three coronary arteries protected 75% of the animals. Applied clinically in over 100 patients, the operation resulted in 90% improvement. To obtain complete myocardial revascularization, the right internal mammary artery has been used as a fourth source of extra-coronary blood. In 57 animals, the right internal mammary arteries were implanted into the anterior walls of the right ventricle; in 80% this vessel formed anastomoses with the right coronary tree, and in 65% with the right and left coronary arteriolar systems. Six patients are described who underwent right internal mammary artery implantation; five of these in addition had the combined operation of left internal mammary artery implant, epicardiectomy and free omental graft. All patients had completely blocked right coronary arteries; in addition, five had advanced disease of the left coronary arterial tree.     

Revascularization in the acute coronary syndromes

Coronary heart disease is the leading cause of death worldwide, and occurs when the coronary arteries are unable to supply adequate oxygenated blood to the myocardium, which in turn can lead to ischemia and infarction of myocardial tissue. There are three options for revascularization in the setting of acute coronary syndromes. In select patients, coronary artery bypass surgery remains an option. Thrombolytics were initially the mainstay of therapy, which has now shifted to angioplasty, with or without stents, when readily available. Revascularization has been demonstrated to improve patient outcomes, and has evolved rapidly in the recent past.     

Debate: PCI vs CABG: a moving target, but we are gaining

The treatment of patients with coronary artery disease continues to evolve; all three strategies – medical therapy, surgical revascularization, and percutaneous coronary intervention – have changed. Medical therapy with intense risk-factor modification and treatment with a statin, aspirin, and angiotensin-converting enzyme (ACE) inhibitors, should be used unless contraindicated. Surgical therapy has also changed with the introduction of minimally invasive, beating heart surgery. Percutaneous coronary intervention has perhaps changed the most radically with adjunctive therapy – glycoprotein IIb/IIIa inhibitors, thienopyridines, and reliance on stent implantation. The future, with new distal protection devices and drug-coated stents, should continue to see increased numbers of patients who can benefit from percutaneous intervention.