Angiographic evaluation of graft patency in minimally invasive direct coronary artery bypass grafting

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.

Deleterious effects of cardiopulmonary bypass in coronary artery surgery and scientific interpretation of off-pump's logic

Cardiopulmonary bypass (CPB) has been suggested to be a cause of complex systemic inflammatory response that significantly contributes to several adverse postoperative complications. In the last few years, off-pump coronary artery bypass grafting (OPCAB) has gained widespread attention as an alternative technique to conventional on-pump coronary artery bypass grafting (ONCAB). However, a degree of uncertainty regarding the relative merits of ONCAB and OPCAB continues to be a significant issue. Surgeons supporting off-pump surgery, state that the avoidance of the CPB leads to significantly reduced myocardial ischemia-reperfusion injury, postoperative systemic inflammatory response and other biological derangements, a feature that may improve the clinical outcomes. However, perfection in perioperative care, surgical technique and methods of attenuating the untoward effects of CPB has resulted in better clinical outcome of ONCAB as well. Possible reasons of these controversial opinions are that high-quality studies have not comprehensively examined relevant patient outcomes and have enrolled a limited range of patients. Some studies may have been too small to detect clinically important differences in patient outcomes between these two modalities. We present a review of the available scientific interpretation of the literature on OPCAB with regard to safety, hemodynamic changes, inflammation, myocardial preservation and oxidative stress. We also sought to determine from different reported retrospective and randomized control studies, the initial and the long-term benefits of this approach, despite the substantial learning curve associated with OPCAB.

Long-Term Results of the Endoscopic Atraumatic Coronary Artery Bypass

BACKGROUND

This retrospective study was undertaken to determine the long-term angiographic patency and clinical outcomes of the endoscopic atraumatic coronary artery bypass (endoACAB) procedure.

METHODS

Between November 1997 and March 2005, 607 consecutive patients underwent an endoACAB consisting of (1) unilateral or bilateral manual, thoracoscopic internal mammary artery (IMA) harvesting, (2) creation of a needle-directed access port in the thoracic soft tissue (non-rib-spreading), (3) cardiac positioning and stabilization using port-based instrumentation, and (4) off-pump, direct-vision, hand-sewn anastomoses to the left anterior descending (LAD), diagonal, obtuse marginal, or main right coronary arteries, or a combination. Mean follow-up time was 18.0 +/- 16.0 months (range, 2.0 to 85.7 months).

RESULTS

The IMA was used to graft the LAD in all cases. A total of 721 anastomoses were constructed using 636 conduits. Thirty-day mortality was 1.0% (6/607). A total of 379 (62.4%) had coronary angiography after operation at a mean of 18.4 +/- 17.0 months. The overall patency for the LIMA to LAD was FitzGibbon A, 95.2% (324/340), and FitzGibbon A and B, 98.5% (335/340). At 5 years, event-free survival was 92% +/- 2.4%.

CONCLUSIONS

The clinical outcome and angiographic patency of grafting the LAD with the LIMA off pump through a non-rib-spreading incision compares favorably with the reported data of arrested heart grafting through a median sternotomy. The endoACAB offers an excellent alternative for patients with LAD disease as a stand-alone procedure, a multivessel grafting procedure in selected patients, or as part of a hybrid procedure in conjunction with a percutaneous intervention.

Results of the Prospective Multicenter Trial of Robotically Assisted Totally Endoscopic Coronary Artery Bypass Grafting

BACKGROUND

Robotic technology has been proven safe and efficacious in the performance of mitral valve repair and atrial septal defect repair. This report describes a Food and Drug Administration-sanctioned multicenter study of the safety and efficacy of the da Vinci system (Intuitive Surgical, Inc, Mountain View, CA) for totally endoscopic coronary artery bypass (TECAB) surgery.

METHODS

Patients requiring left anterior descending (LAD) coronary artery revascularization were eligible. The procedure was performed with femoro-femoral cardiopulmonary bypass (CPB), endoaortic balloon occlusion, and thoracoscopy. All aspects of the procedure were performed with the robotic system, from internal mammary artery harvest to coronary anastomosis.

RESULTS

Ninety-eight patients requiring single-vessel LAD revascularization were enrolled at 12 centers. Thirteen patients (13%) were excluded intraoperatively (eg, failed femoral cannulation, inadequate working space). In 85 patients (69 men, age 58 +/- 10 years) who underwent TECAB, CPB time was 117 +/- 44 minutes, cross-clamp time was 71 +/- 26 minutes, and hospital length of stay was 5.1 +/- 3.4 days. There were five (6%) conversions to open techniques. There were no deaths or strokes, one early reintervention, and one myocardial infarction (1.5%). Three-month angiography was performed in 76 patients, revealing significant anastomotic stenoses (> 50%) or occlusions in 6 patients. Overall freedom from reintervention or angiographic failure was 91%.

CONCLUSIONS

Robotic TECAB was accomplished with no mortality, low morbidity, and angiographic patency and reintervention rates comparable with published data. Although the use of CPB was a limitation of the technique, this experience represents a step toward more advanced procedures, such as multivessel or off-pump TECAB.

Clinical and six-month angiographic evaluation of coronary arterial graft interrupted anastomoses by use of a self-closing clip device: a multicenter prospective clinical trial

OBJECTIVES

To evaluate the safety and effectiveness of a self-closing surgical clip with an interrupted technique in left internal thoracic artery to left anterior descending artery bypass grafting.

METHODS

Eighty-two patients were enrolled and treated (February 2000 through August 2001) in a prospective, nonrandomized, multicenter trial. Left internal thoracic artery to left anterior descending artery anastomoses were performed in 60 off-pump coronary artery bypasses (73%), 12 conventional coronary artery bypass grafting (15%), and 10 minimally invasive direct coronary artery bypass (12%) procedures. Angiograms (64 to 383 days, mean 200 days) were obtained on 63 patients (77%). Qualitative and quantitative angiographic assessment was performed by an independent core laboratory.

RESULTS

The self-closing surgical clip was used for 82 left internal thoracic artery to left anterior descending artery interrupted anastomoses without the requirement for knot tying or primary suture management. Minimum left internal thoracic artery to left anterior descending artery anastomosis time was 3 minutes. There was one perioperative and one late death (both not heart related) and one reexploration for bleeding unrelated to the anastomotic site. FitzGibbon grades were as follows: A (n = 60, 95.2%), B (n = 3, 4.8%) including one kinked left internal thoracic artery, and O (n = 0, 0%). Quantitative analysis (n = 57) showed mean lumen diameters of left internal thoracic artery proximal to the anastomosis of 2.1 mm, at anastomosis of 2.0 mm, and in the left anterior descending artery distal to the anastomosis of 1.9 mm. The average ratio of the anastomosis to the left anterior descending artery diameter was 1.14 (0.45 to 1.93). Anastomotic stenosis as a percentage of average left internal thoracic artery to left anterior descending artery diameter was -2.3%, comparing favorably with results (23% to 24%) reported from the Patency, Outcomes, Economics, Minimally invasive direct coronary artery (POEM) bypass study.

CONCLUSIONS

The interrupted technique, facilitated by a self-closing anastomotic clip, yields favorable 6-month angiographic results when compared with other published studies.