Current status of cardiovascular surgery in Japan, 2013 and 2014: A report based on the Japan Cardiovascular Surgery Database 3. Coronary artery bypass surgery

OBJECTIVE AND METHODS

Data on isolated coronary artery bypass grafting (CABG) performed in 2013 and 2014, and registered in the Japan Cardiovascular Surgery Database were reviewed for preoperative characteristics, postoperative outcomes, and choice of graft material for the left anterior descending artery (LAD).

RESULTS

Isolated CABG was performed off-pump in 54.7% of cases, and graft material for the LAD was left internal thoracic artery in 74.3% and right internal thoracic artery in 15.6%. Operative mortality was 2.0% in elective cases, 8.2% in emergency cases, and 3.0% overall. In elective cases, operative mortality was 1.1% for off-pump CABG compared with 3.0% for on-pump CABG.

CONCLUSIONS

Clinical results of our isolated CABG were reasonable and acceptable.

Off-Pump Coronary Artery Bypass Surgery

Off-pump coronary artery bypass surgery has been adopted enthusiastically worldwide. However, despite more than 6 years’ experience and refinement, many surgeons use it only sporadically and some hardly at all. This reluctance persists despite support for the procedure because of the lack of properly designed risk models and/or randomized studies. Although it has not been overwhelmingly shown that off-pump surgery is superior to the conventional on-pump procedure, the technique has its place in our specialty. It has been shown to be better for noncritical end points in selected patients in the hands of selected surgeons. That there are differences in surgical skill among surgeons is something we all know but rarely discuss in public. Until now, disparities in skill have been most salient with uncommon and extraordinarily challenging operations. Perhaps the off-pump procedure should be regarded as the “challenging” aspect of coronary artery bypass surgery, and self-restraint may need to remain in force if we are to continue to achieve the highest level of clinical excellence.

Trends in aortic clamp use during coronary artery bypass surgery: effect of aortic clamping strategies on neurologic outcomes

OBJECTIVE

The purpose of the present study was to determine the effect of different clamping strategies during coronary artery bypass grafting on the incidence of postoperative stroke.

METHODS

In the present case-control study, all patients at Emory hospitals from 2002 to 2009 with postoperative stroke after isolated coronary artery bypass grafting (n = 141) were matched 1:4 to a contemporaneous cohort of patients without postoperative stroke (n = 565). The patients were matched according to the Society of Thoracic Surgeons' predicted risk of postoperative stroke score, which is based on 26 variables. The patients who received on-pump and off-pump coronary artery bypass grafting were matched separately. Multiple logistic regression analysis with adjusted odds ratios was performed to identify the operative variables associated with postoperative stroke.

RESULTS

Among the on-pump cohort, the single crossclamp technique was associated with a decreased risk of stroke compared with the double clamp (crossclamp plus partial clamp) technique (odds ratio, 0.385; P = .044). Within the on-pump cohort, no significant difference was seen in the incidence of stroke according to clamp use. Epiaortic ultrasound of the ascending aorta increased from 45.3% in 2002 to 89.4% in 2009. From 2002 to 2009, clamp use decreased from 97.7% of cases to 72.7%.

CONCLUSIONS

During on-pump coronary artery bypass grafting, the use of a single crossclamp compared with the double clamp technique decreased the risk of postoperative stroke. The use of any aortic clamp decreased and epiaortic ultrasound use increased from 2002 to 2009, indicating a change in the operative technique and surgeon awareness of the potential complications associated with manipulation of the aorta.

[Renaissance of surgery for coronary artery disease]

Coronary bypass surgery is now a standard therapy for the treatment of coronary heart disease. Developed in the 1960s, the coronary artery bypass operation was the most performed operation at all in the 1980s. There was and still is rapidly advancing. The recovery of coronary surgery was held back in the 1970s with the introduction of heart catheterisation. To date, the number of interventional revascularizations has increased, while the number of bypass operations has reached a plateau. 30 resp. 40 years after the introduction of the two techniques it is still controversial which is the method of choice. According to the latest guidelines there is strong evidence that coronary artery surgery for patients with complex coronary artery disease is the gold standard: A Renaissance of bypass surgery.

Subxiphoid multi-arterial OPCAB: surgical technique and initial case report

BACKGROUND

The surgical technique of transsternal coronary artery bypass grafting (CABG) has remained relatively stagnant for the past three decades. Unlike general and orthopedic surgery, cardiac surgery has made very little progress in converting our most common procedure into a minimally invasive alternative. Minithoracotomy techniques introduced in 1995 enjoyed a brief period of popularity but were inherently single vessel (LIMA-LAD) procedures and thus not an answer to the need for a less invasive multivessel operation. Totally endoscopic CABG has been performed in a small number of cases but the learning curve is very steep and the rate of conversion to open surgery remains high with only a few successful multivessel cases. There remains a great need for a less invasive approach that has the potential to graft all coronary targets without disturbing the chest wall and which can be performed by all current and future surgeons with acceptable hospital costs. A small subxiphoid incision has been used for single vessel grafting to anterior or inferior targets, but until now lateral wall grafting has not been considered possible. Development of a successful multivessel subxiphoid technique on the beating heart, including lateral wall grafting, is now reported in this article.

METHODS

Subxiphoid multi-arterial bypass grafting was performed on a 79-year-old male using commercially available equipment but modified surgical techniques. Instead of midline sternotomy, full exposure to the heart was obtained by four essential steps: (1) removal of the xiphoid process, (2) vertical lifting of the lower sternum, (3) caudal retraction of the diaphragm, and (4) spreading of the wound using a specific retractor to create an adequate working portal. Both internal mammary arteries were harvested for their full length as skeletonized conduits using only direct vision (headlight and loupes). Off-pump distal anastomoses to the left anterior descending (LAD) and first obtuse marginal branch of the circumflex (OMB-1) were performed using available stabilizer systems. The obtuse marginal was exposed using the Medtronic Starfish suction-positioner without any hemodynamic compromise. The wound was closed with a simple running fascial suture and the patient discharged on postoperative day 4 with no complications and no angina.

CONCLUSIONS

Most practicing surgeons are reluctant to perform multiple distal grafts through small incisions because of the difficulty in simultaneously mastering a host of new skills at the same time (robotics, endoscopics, beating heart techniques). The subxiphoid approach offers the potential to perform distal anastomoses to all regions of the beating heart with excellent exposure while utilizing the same skill sets that surgeons now possess. There is potential that further evolution of this technique will permit outpatient CABG while providing long-term clinical outcomes superior to coronary stenting.

Living with off-pump coronary artery surgery: evolution, development, and clinical potential for coronary heart disease patients

The enormous progress in interventional cardiology during the last 10 years has resulted in a major change in the spectrum of patients referred for coronary bypass surgery. These patients are older and sicker and frequently have had previous percutaneous coronary interventions. Consequently, cardiac surgery is responding by adding new surgical techniques: off-pump open-chest coronary bypass surgery (OPCAB), minithoracotomy bypass surgery, videothoracoscopic (robotic) procedures, etc. Several registries published to date have proved OPCAB to be safe and clinically effective. Randomized studies and meta-analysis research in this field provide scientific support and suggest that myocardial, renal, and neurological functions, amongst others, are better preserved by OPCAB than by classic techniques that use a cardiopulmonary bypass pump (CPB). Moreover, avoidance of CPB yields significantly reduced oxidative stress and systemic inflammatory response. This results in higher safety for ischemic heart disease patients undergoing revascularization, thus offsetting the propensity to lower costs. The present review examines the physiological advantages and clinical outcomes of this simple mode of myocardial revascularisation and evaluates the wider implications arising from its evolution.

Off-pump coronary artery bypass grafting: a case report

It is easy to take for granted the seemingly effortless way cardiovascular surgeons are able to bypass atherosclerotic coronary arteries. The process used today was developed over many years of rigorous study, experimentation, success, and failure. Early cardiac surgery was performed blindly, through small incisions, on a beating heart. Advances in medicine allowed surgery to be performed on hearts stilled by cardioplegic arrest, while the circulation was continued through the use of a cardiopulmonary bypass (CPB) machine. The development of the CPB machine allowed surgeons to perform the delicate work of coronary artery bypass grafting (CABG), first attempted on dogs, and then humans. This article briefly outlines the historical evolution of cardiac surgery that led to the development of the technology necessary to perform off-pump coronary artery bypass grafting (OPCAB). A case report of a 72-year-old female who underwent OPCAB is outlined. Included is a discussion of some of the benefits and potential complications of CABG and OPCAB. Anesthetic considerations for OPCAB procedures also are presented.

[Off-pump coronary artery bypass grafting in Japan]

The number of coronary artery bypass grafting (CABG) procedures has reached more than 20,000 per year in Japan, and the operative mortality rate has decreased to less than 1.5% including emergent surgery. The mortality and morbidity rates of CABG are still high in patients with risk factors such as cerebrovascular disease, chronic renal failure on hemodialysis, atheromatous and calcified ascending aorta, and older age when cardiopulmonary bypass is used. Minimally invasive direct coronary bypass on a beating heart through a small left lateral anterior thoracotomy, in which the left internal thoracic artery (LITA) is used to revascularize the left anterior descending artery, was introduced for high-risk patients with single-vessel disease in the mid-1990s, although is not widely performed at present. Since the late 1990s off-pump coronary artery bypass grafting (OPCAB) has been widely performed as a treatment for multivessel disease through a median sternotomy with the evolution of stabilizers and apical suction devices, refined anesthetic management, and sophisticated surgical techniques. In 2004, 60% of all CABG procedures in Japan were performed without cardiopulmonary bypass. Due to competition from percutaneous coronary intervention with drug-eluting stents and better long-term outcomes, CABG with arterial grafts alone was carried out in 52% of total cases and in 66% of OPCAB cases. OPCAB is becoming the standard CABG in Japan.

Off pump coronary artery bypass surgery for significant left ventricular dysfunction: safety, feasibility, and trends in methodology over time--an early experience

OBJECTIVE

To examine the safety and applicability of off pump coronary artery bypass surgery (OPCAB) in patients with significant left ventricular dysfunction and to discuss the clinical implications for the surgical methods.

DESIGN

Retrospective study.

SETTING

Tertiary care university affiliated referral centre.

PARTICIPANTS

353 consecutive patients with preoperative left ventricular ejection fraction < or = 35% who underwent coronary artery bypass over a three year period.

MAIN OUTCOME MEASURES

Postoperative morbidity and mortality.

METHODS

144 patients operated by OPCAB were compared with 209 patients operated by conventional coronary artery bypass. Multivariate and univariate analyses were performed on the pre- and postoperative variables to predict risk factors associated with hospital morbidity and mortality.

RESULTS

Patients in the OPCAB group were more likely to be women and to have congestive heart failure, chronic obstructive pulmonary disease, hypertension, and diabetes; patients in the on pump group were more likely to have had a recent myocardial infarction and to have more severe angina pectoris and an urgent/emergent status. The groups did not differ significantly in length of stay, major postoperative complication rates, or mortality. Comparison of the impact of the procedures on surgical methods over time showed an increase in the use of OPCAB (13% to 67%), without any impact on morbidity or mortality.

CONCLUSIONS

OPCAB is feasible and applicable for patients with depressed left ventricular function. This high risk group can potentially benefit from the off pump approach.

Coronary artery bypass grafting on the beating heart: surgical revascularization for the next decade?

This review considers whether coronary artery bypass grafting (CABG) performed on the beating heart (off-pump or OPCAB) will supersede conventional CABG utilizing cardiopulmonary bypass (CPB) and cardioplegic arrest as the accepted gold standard. Randomized controlled trials, case-matched reports and observational studies have demonstrated lower morbidity in off-pump compared to conventional on-pump CABG with equivalent mid-term outcome at a significantly lower cost. Patients referred for surgical revascularization are increasingly elderly with more co-morbid medical conditions and elimination of CPB-related morbidity in these groups is associated with the most pronounced improvements in outcome, at least in observational studies. Long-term outcome, and in particular, long-term graft patency following OPCAB has not yet been reported. A barrier to the more widespread acceptance of OPCAB is the poor provision for training in off-pump techniques although structured cardiothoracic training that includes OPCAB surgery has been shown to be both possible and safe for patients. The evidence available to date therefore strongly supports the assertion that OPCAB may become the new gold standard in surgical revascularization. Whether it will ultimately replace conventional CABG, however, is dependent on the results of long-term patency studies and the wider development of adequate training programmes.