Seven-Year Follow-up After Minimally Invasive Direct Coronary Artery Bypass: Experience With More Than 1300 Patients

Minimally invasive direct coronary artery bypass versus off-pump coronary surgery through sternotomy

INTRODUCTION

Although it is not a new technique, minimally invasive direct coronary artery bypass (MIDCAB) is employed only by a few surgeons in the UK. We compared our experience with MIDCAB with that of single vessel off-pump coronary artery bypass (OPCAB) graft surgery through a standard median sternotomy.

METHODS

Patients who underwent either MIDCAB or OPCAB between April 2008 and July 2011 were reviewed. Exclusion criteria included patients with an ejection fraction of <0.5 or previous cardiac surgery. Data were obtained retrospectively from our prospective database, medical records and through general practitioners.

RESULTS

Overall, 74 patients were analysed in the MIDCAB group and 78 in the OPCAB group. Their demographics and EuroSCORE (European System for Cardiac Operative Risk Evaluation) values were comparable (p>0.05). There was no statistically significant difference in the two groups in terms of mortality, recurrent myocardial infarction, postoperative stroke, wound infection, atrial fibrillation or need for reintervention. The MIDCAB group had six conversions to a sternotomy. Eight patients in each group required blood transfusion, with the average transfusion being 1.8 units in the MIDCAB group and 3.2 units in the OPCAB group. The mean duration of ventilation and intensive care unit stay was 5.0 hours and 38.4 hours in the MIDCAB group and 5.4 and 47.8 hours in the OPCAB group. The mean hospital stay was significantly reduced in the MIDCAB population (6.1 vs 8.5 days, p<0.05).

CONCLUSIONS

MIDCAB can be performed safely in appropriately selected patients with outcomes comparable with OPCAB. The potential benefits include shorter hospital stay, reduced need for blood transfusion and faster recovery.

Minimally invasive direct coronary artery bypass in the era of percutaneous coronary intervention

AIM

Minimally invasive coronary artery bypass (MIDCAB) allows revascularization of the left anterior descending coronary (LAD) artery through a less traumatic surgical approach. However, the procedure is technically challenging and concern still exists, mainly based on graft patency. The purpose of this study is to critically evaluate short and long-term benefits of this surgical treatment.

METHODS

Between June 1997 and July 2012, 306 patients underwent MIDCAB on LAD. The mean age was 62 ± 10 years (range, 32-87 years) and 264 patients (86.3%) were men. Mean ejection fraction was 54%. Eighty-nine procedures (29.1%) were performed using a hybrid approach by means of MIDCAB and postoperative (60 patients, 67.4%) or preoperative (29 patients, 32.6%) percutaneous interventions on non-LAD vessels. A EuroScore more than 6 was found in 43 (14%) patients. The average follow-up time was 9.5 ± 3.2 years and was 89% complete.

RESULTS

Six patients (1.9%) required intraoperative conversion to sternotomy, whereas cardiopulmonary bypass institution after the sternotomy was necessary in one. Postoperative acute myocardial infarction occurring nine patients (2.9%), low output syndrome in four (1.3%). Postoperative mortality was 1.6% (n = 5), and perioperative stroke rate 0.6% (n = 2). Five and 10-year survival were 94.1 and 86.9%, respectively. Freedom from death due to cardiac events and major cardiac and cerebral events at 10 years was, respectively, 97.1 and 92.1%.

CONCLUSIONS

The results confirm the favorable short and long-term results of the MIDCAB procedure. MIDCAB, in experienced centers, can represent an alternative treatment option for LAD disease.

New technologies in coronary artery surgery

Coronary artery disease remains the leading cause of death in developed countries. Major recent studies such as SYNTAX and FREEDOM have confirmed that coronary artery bypass grafting (CABG) remains the gold standard treatment in terms of survival and freedom from myocardial infarction and the need for repeat revascularization. The current review explores the use of new technologies and future directions in coronary artery surgery, through 1) stressing the importance of multiple arterial conduits and especially the use of bilateral mammary artery; 2) discussing the advantages and disadvantages of off-pump coronary artery bypass; 3) presenting additional techniques, e.g. minimally invasive direct coronary artery bypass grafting, hybrid, and robotic-assisted CABG; and, finally, 4) debating a novel external stenting technique for saphenous vein grafts.

Surgical pitfalls of minimally invasive direct coronary artery bypass procedure from the viewpoint of a surgeon in the learning curve

Introduction

Minimally invasive direct coronary artery bypass grafting (MIDCAB) offers arterial revascularization of the left anterior descending (LAD) coronary artery especially in lesions unsuitable for percutaneous coronary interventions. By avoidance of sternotomy and cardiopulmonary bypass its invasiveness is less than that of conventional bypass surgery.

Aim

We in this study discuss our surgical experience in the MIDCAB procedure.

Material and methods

Thirteen patients were operated on with the MIDCAB procedure. The inclusion criteria for MIDCAB were pure LAD disease totally occluded or severely stenotic. Patient demographics and preoperative and postoperative data were analyzed.

Results

Mean age of the patients was 60.0 ±8.6 years. Patients’ preoperative and postoperative levels of cardiac CK-MB (creatine kinase MB) were not significantly different (p = 0.993). However, cardiac troponin I (p < 0.001), hemoglobin (p < 0.001) and hematocrit (p < 0.001) were significantly different. No perioperative myocardial infarctions or cerebrovascular accidents were seen. The patients were discharged at a mean day of 4.77 with oral antiaggregant therapy. No mortality was seen in the study population.

Conclusions

Minimally invasive direct coronary artery bypass is associated with few perioperative complications. Minimally invasive direct coronary artery bypass in our experience is a very good option for single vessel LAD disease.

Conversion to sternotomy during sternal-sparing coronary artery surgery

Conversion to a full sternotomy may complicate up to 1.8% of the sternal-sparing coronary artery surgery. Left internal mammary artery injury and anastomotic problems are the common causes. The purpose of this article is to retrospectively review the outcomes of six patients that required conversion to sternotomy during minimally invasive direct coronary artery bypass and also to point out technical aspects in order to avoid such a complication.

Surgical myocardial revascularization versus percutaneous coronary intervention with drug-eluting stents in octogenarian patients

OBJECTIVE

Our goal was to compare the clinical outcomes of octogenarian (or older) patients who are referred for either surgical or percutaneous coronary revascularization.

METHODS

We retrospectively evaluated the outcomes of all patients 80 years of age who had undergone coronary artery bypass grafting (CABG) with an internal mammary artery or had undergone a percutaneous coronary intervention (PCI) with a sirolimus-eluting stent to the left anterior descending artery in our center between May 2002 and December 2006.

RESULTS

Of the 301 patients, 120 underwent a PCI, and 181 underwent CABG. Surgical patients had higher rates of left main disease, triple-vessel disease, peripheral vascular disease, emergent procedures, and previous myocardial infarctions (39.7% versus 3.3% [P = .001], 76.1% versus 28.3% [P = .0001], 19.6% versus 7.5% [P = .004], 15.8% versus 2.5% [P = .0001], and 35.9% versus 25% [P = .04], respectively). CABG patients had a higher early mortality rate (9.9% versus 2.5%, P = .01). There were no differences in 1- and 4-year actuarial survival rates, with rates of 90% and 68%, respectively, for the PCI group and 85% and 71% for the CABG group (P = .85). The rates of actuarial freedom from major adverse cardiac events (MACEs) at 1 and 4 years were 83% and 75%, respectively, for the PCI group, and 86% and 78% for the CABG group (P = .33). The respective rates of freedom from reintervention were 87% and 83% for the PCI group, versus 99% and 97% for the CABG group (P < .001). The 4-year rate of freedom from recurring angina was 58% for the PCI group, versus 88% for CABG patients (P < .001). Revascularization strategy was not a predictor of adverse outcome in a multivariable analysis.

CONCLUSION

Octogenarian CABG patients were sicker and experienced a higher rate of early mortality. The 2 strategies had similar rates of late mortality and MACEs, with fewer reinterventions and recurring angina occurring following surgery.

Review of a 13-year single-center experience with minimally invasive direct coronary artery bypass as the primary surgical treatment of coronary artery disease

BACKGROUND AND AIM OF THE STUDY

In this study, we review our experience with 1768 minimally invasive direct coronary artery bypass (MIDCAB) operations. The focus is on long-term outcome with more than 10 years of follow-up.

METHODS

All patients undergoing standard MIDCAB between 1996 and 2009 were included. For all 1768 patients, pre-, intra-, and postoperative data could be completed. Long-term follow-up information about health status, major adverse cardiac and cerebrovascular events (MACCE), and freedom from angina was collected annually via questionnaire or personal contact. Five-year follow-up is available for 1313 patients, and 10-year-follow-up is available for 748 patients. A multivariate Cox regression analysis was performed to determine risk factors for long-term outcome.

RESULTS

Mean age was 63.4 ± 10.8 years, mean ejection fraction was 60.0% ± 14.2%, and perioperative mortality risk calculated by logistic EuroSCORE was 3.8 ± 6.2%. In 31 patients (1.75%) intraoperative conversion to sternotomy was necessary. Early postoperative mortality was 0.8% (15 patients); 0.4% (7 patients) had a perioperative stroke. Seven hundred twelve patients received routine postoperative angiogram, showing 95.5% early graft patency. Short-term target vessel reintervention was needed in 59 patients (3.3%) (11 percutaneous transluminal coronary angioplasty (PTCA)/stent, 48 re-operation). Kaplan-Meyer analysis revealed a 5-year survival rate of 88.3% (95% confidence interval [CI], 86.6% to 89.9%) and a 10-year-survival rate of 76.6% (95% CI, 73.5% to 78.7%). The freedom from MACCE and angina after 5 and 10 years was 85.3% (95% CI, 83.5% to 87.1%) and 70.9% (95% CI, 68.1% to 73.7%), respectively.

CONCLUSIONS

MIDCAB is a safe operation with low postoperative mortality and morbidity. With excellent short-term and long-term results, it is a very good alternative compared to both percutaneous coronary intervention (PCI) and conventional surgery.

The golden age of minimally invasive cardiothoracic surgery: current and future perspectives

Over the past decade, minimally invasive cardiothoracic surgery (MICS) has grown in popularity. This growth has been driven, in part, by a desire to translate many of the observed benefits of minimal access surgery, such as decreased pain and reduced surgical trauma, to the cardiac surgical arena. Initial enthusiasm for MICS was tempered by concerns over reduced surgical exposure in highly complex operations and the potential for prolonged operative times and patient safety. With innovations in perfusion techniques, refinement of transthoracic echocardiography and the development of specialized surgical instruments and robotic technology, cardiac surgery was provided with the necessary tools to progress to less invasive approaches. However, much of the early literature on MICS focused on technical reports or small case series. The safety and feasibility of MICS have been demonstrated, yet questions remain regarding the relative efficacy of MICS over traditional sternotomy approaches. Recently, there has been a growth in the body of published literature on MICS long-term outcomes, with most reports suggesting that major cardiac operations that have traditionally been performed through a median sternotomy can be performed through a variety of minimally invasive approaches with equivalent safety and durability. In this article, we examine the technological advancements that have made MICS possible and provide an update on the major areas of cardiac surgery where MICS has demonstrated the most growth, with consideration of current and future directions.

Hybrid coronary revascularization: a review

The long-term benefits of a left internal mammary artery bypass graft compared to the left anterior descending artery have been well described. The use of drug-eluting stents has minimized the morbidity of revascularization. Hybrid coronary revascularization is the planned use of minimally invasive surgical techniques for left internal mammary artery-left anterior descending artery grafting and the use of percutaneous coronary intervention for nonleft anterior descending coronary artery target revascularization. The optimal timing and order of revascularization in hybrid coronary revascularization remains unclear.

Is there an optimal minimally invasive technique for left anterior descending coronary artery bypass?

Background

The aim of this retrospective study was to evaluate the clinical outcome of three different minimally invasive surgical techniques for left anterior descending (LAD) coronary artery bypass grafting (CABG): Port-Access surgery (PA-CABG), minimally invasive direct CABG (MIDCAB) and off-pump totally endoscopic CABG (TECAB).

Methods

Over a decade, 160 eligible patients for elective LAD bypass were referred to one of the three techniques: 48 PA-CABG, 53 MIDCAB and 59 TECAB. In MIDCAB group, Euroscore was higher and target vessel quality was worse. In TECAB group, early patency was systematically evaluated using coronary CT scan. During follow-up (mean 2.7 ± 0.1 years, cumulated 438 years) symptom-based angiography was performed.

Results

There was no conversion from off-pump to on-pump procedure or to sternotomy approach. In TECAB group, there was one hospital cardiac death (1.7%), reoperation for bleeding was higher (8.5% vs 3.7% in MIDCAB and 2% in PA-CABG) and 3-month LAD reintervention was significantly higher (10% vs 1.8% in MIDCAB and 0% in PA-CABG). There was no difference between MIDCAB and PA-CABG groups. During follow-up, symptom-based angiography (n = 12) demonstrated a good patency of LAD bypass in all groups and 4 patients underwent a no LAD reintervention. At 3 years, there was no difference in survival; 3-year angina-free survival and reintervention-free survival were significantly lower in TECAB group (TECAB, 85 ± 12%, 88 ± 8%; MIDCAB, 100%, 98 ± 5%; PA-CABG, 94 ± 8%, 100%; respectively).

Conclusions

Our study confirmed that minimally invasive LAD grafting was safe and effective. TECAB is associated with a higher rate of early bypass failure and reintervention. MIDCAB is still the most reliable surgical technique for isolated LAD grafting and the least cost effective.

Combined Transapical Aortic Valve Replacement and Minimally Invasive Direct Coronary Bypass Grafting�A New Concept for Selected High-Risk Patients

Background: Transcatheter aortic valve implantation and minimally invasive direct coronary artery bypass (MIDCAB) procedures are both off-pump treatment options for a subset of higher-risk patients. We present a new, minimally invasive surgical concept involving combining the procedures and performing them through the same thoracic access in a patient with a vascular disorder.Case Report: We report on a 78-year-old patient with symptomatic calcified aortic stenosis and a critical lesion of the left anterior descending coronary artery. In addition, Rendu-Osler-Weber disease was diagnosed. He was successfully treated with combined off-pump transapical, transcatheter aortic valve implantation and MIDCAB grafting. The initial postoperative recovery was good; however, the patient died 3 months postoperatively from septic complications.Conclusion: This combined procedure performed through the same anterolateral incision was technically feasible and may be a promising, minimally invasive approach for selected patients.

Long-Term Survival after Minimal Invasive Direct Coronary Artery Bypass (MIDCAB) Surgery in Patients with Low Ejection Fraction

Objective

The long-term survival after minimal invasive direct coronary artery bypass (MIDCAB) surgery to any coronary territory in patients with ejection fraction of ≤30% was investigated for the first time in literature.

Methods

Seventy-three patients with primary MIDCAB and 89 patients with reoperative MIDCAB were studied including preoperative risk factors, operative details, early postoperative complications, and survival up to 10 years postoperatively.

Results

Despite the high-risk profile of the patients, the MIDCAB approach for targeted revascularization resulted in excellent short-term results. Ventricular arrhythmia contributed to four of six early deaths. Survival at 5 years postoperatively was 62.5% for primary MIDCAB and 43.2% for reoperative MIDCAB and at 10 years was 36.9% and 29.5%, respectively. Functionally complete vascularization correlates with significantly better long-term survival particularly in primary MIDCAB procedures.

Conclusions

MIDCAB is a valuable option for targeted revascularization in high-risk patients with low ejection fraction and reoperation.

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 multi-disciplinary approach requires strong collaboration between cardiac surgeons, vascular surgeons, and interventional cardiologists to obtain optimal patient outcomes.

Current state of surgical myocardial revascularization

Despite increasing competition from percutaneous interventions and other novel methods of non-surgical coronary revascularization, coronary artery bypass grafting (CABG) remains one of the most definitive and durable treatments for coronary artery disease, especially for those patients with extensive and diffuse disease. In recent years the CABG procedure itself has undergone innovation and evolution. This review article provides a brief historical perspective on the procedure, and examines the current state of modern variations including off-pump, limited-access, and robotic-assisted CABG.

Minimally Invasive Direct Coronary Artery Bypass as a Primary Strategy for Reoperative Myocardial Revascularization

Objective

Conventional reoperative coronary artery bypass grafting is associated with risk of sternal re-entry, injury to patent grafts, and embolization from diseased grafts. Sternal sparing minimally invasive direct coronary artery bypass (MIDCAB) avoids such risks in cases where it is technically feasible. We sought to examine in-hospital outcomes of reoperative MIDCAB surgery.

Methods

We recorded prospective standardized data from the New York Cardiac Surgical Reporting System database of 369 reoperative MIDCAB cases from 1996 to 2006 and compared with 822 primary MIDCAB patients in the same time period. We compared the preoperative risk profile and postoperative in-hospital outcomes and length of stay for both groups.

Results

There was a significantly higher risk profile typical of the reoperative patient population (P < 0.001 for stroke, peripheral/cerebrovascular disease, extensive aortic calcification, renal failure, and left ventricular ejection fraction <40%) compared with the primary MIDCAB group. Despite this fact, there was no difference in the in-hospital outcomes and length of hospital stay between the two groups.

Conclusions

Reoperative MIDCAB provides targeted coronary revascularization and avoids hazards of sternal re-entry, graft injury and manipulation, and deleterious effects of cardiopulmonary bypass. This hastens recovery and provides excellent early outcomes equivalent to primary MIDCAB procedures.

Coronary artery bypass grafting without full sternotomy

Coronary artery bypass grafting is performed without full sternotomy in selected patients because it is less invasive. Left internal thoracic artery-left anterior descending artery bypass (LITA-LAD bypass) via a small left anterior thoracotomy is a well established procedure, which achieves good graft patency with low mortality and morbidity rates. Multiple revascularization is possible with a limited lateral thoracotomy or L-figure approach. Axillary-coronary bypass and right gastroepiploic artery-right coronary artery bypass (RGEA-RCA bypass) are alternative methods, especially for redo surgery, in selected patients.

The primary and secondary prevention of coronary artery disease: American College of Chest Physicians Evidence-Based Clinical Practice Guidelines (8th Edition)

The following chapter devoted to antithrombotic therapy for chronic coronary artery disease (CAD) is part of the Antithrombotic and Thrombolytic Therapy: American College of Chest Physicians Evidence-Based Clinical Practice Guidelines (8th Edition). Grade 1 recommendations are strong and indicate that the benefits do or do not outweigh risks, burden, and costs. Grade 2 suggests that individual patient values may lead to different choices (for a full understanding of the grading see the "Grades of Recommendation" chapter by Guyatt et al in this supplement, CHEST 2008; 133[suppl]:123S-131S). Among the key recommendations in this chapter are the following: for patients with non-ST-segment elevation (NSTE)-acute coronary syndrome (ACS) we recommend daily oral aspirin (75-100 mg) [Grade 1A]. For patients with an aspirin allergy, we recommend clopidogrel, 75 mg/d (Grade 1A). For patients who have received clopidogrel and are scheduled for coronary bypass surgery, we suggest discontinuing clopidogrel for 5 days prior to the scheduled surgery (Grade 2A). For patients after myocardial infarction, after ACS, and those with stable CAD and patients after percutaneous coronary intervention (PCI), we recommend daily aspirin (75-100 mg) as indefinite therapy (Grade 1A). We recommend clopidogrel in combination with aspirin for patients experiencing ST-segment elevation (STE) and NSTE-ACS (Grade 1A). For patients with contraindications to aspirin, we recommend clopidogrel as monotherapy (Grade 1A). For long-term treatment after PCI in patients who receive antithrombotic agents such as clopidogrel or warfarin, we recommend aspirin (75 to 100 mg/d) [Grade 1B]. For patients who undergo bare metal stent placement, we recommend the combination of aspirin and clopidogrel for at least 4 weeks (Grade 1A). We recommend that patients receiving drug-eluting stents (DES) receive aspirin (325 mg/d for 3 months followed by 75-100 mg/d) and clopidogrel 75 mg/d for a minimum of 12 months (Grade 2B). For primary prevention in patients with moderate risk for a coronary event, we recommend aspirin, 75-100 mg/d, over either no antithrombotic therapy or vitamin K antagonist (Grade 1A).

Cumulative sum failure analysis for eight surgeons performing minimally invasive direct coronary artery bypass

OBJECTIVE

Analysis of average and individual surgical performance for minimally invasive direct coronary artery bypass was used to enhance quality control for that operation.

METHODS

A total of 1441 standard minimally invasive direct coronary artery bypass procedures performed from August 1996 to January 2006 were analyzed for mortality and 10 other major perioperative complications. Learning curves and assessment of perioperative outcome were calculated using descriptive statistics and cumulative sum observed minus expected failure analysis for 8 involved surgeons with a personal experience ranging from 27 to 443 procedures.

RESULTS

The incidence of in-hospital mortality was 0.9% and compared favorably with the predicted mortality calculated by the logistic EuroSCORE (3.6%, P < .01). Cumulative sum analysis revealed that 2 surgeons crossed the 95% reassurance boundary after 50 operations and that 2 surgeons crossed the 95% reassurance boundary after 100 operations. There were significant differences between surgeons with regard to the learning curves and perioperative complications (3.6%-29.6%, P < .01). Two surgeons crossed the 95% alarm-line indicating unacceptably high failure rates.

CONCLUSIONS

Minimally invasive direct coronary artery bypass has become a procedure with low mortality and low complication rates, but results are case-load and surgeon dependent. Cumulative sum analysis is a valuable method allowing for a breakdown of complication rates over time displaying individual surgeons' strengths.