Coronary Stenting and Coronary Bypass Grafting at the Same Time in a Specialty Built Operating Room

Coronary artery disease (CAD) is the leading cause of death in the United States and becomes more common as the population ages (American Heart Association, 2003). The symptoms of CAD may not become perceptible until the condition has advanced to a severe and serious stage, which might explain the large mortality and morbidity rates associated with heart disease.

At this point there are many procedures available to treat CAD all of which aim to improve myocardial blood flow, stop angina, increase exercise ability and ultimately free patients from medications and improve their quality of life. Medications are used to reduce blood pressure and relieve strain on the heart. Cardiologists use angioplasty, which compresses plaque deposits, and stenting, in which a small wire mesh tube is inserted into the diseased artery to revascularize the heart muscle. On-pump coronary artery bypass grafting (CABG) redirects blood flow around clogged vessels of the heart and is commonly used by cardiac surgeons to treat CAD because it has been proven to yield the lowest restenosis rate of all revascularization techniques (Cisowski, 2002). CABG is an effective yet painful and traumatic intervention.

The desire to discover a less distressing approach to coronary artery revascularization has led to a fairly new cardiac hybrid procedure that involves stenting followed by a minimally invasive left internal mammary artery (LIMA) to left anterior descending artery (LAD) bypass graft (Amodeo, 2002). The hybrid procedure for revascularization carries a lower morbidity than does on-pump CABG and is also quickly gaining acceptance in the surgical community (de Canniere et al, 2001). The two procedures of hybrid revascularization are currently performed within 24 to 48 hours of each other with little collaboration between cardiac surgeons and cardiologist.

This study will asses the efficacy and safety of cardiac hybrid surgery that combines stenting and robotic LIMA to LAD grafting in the same procedure in a specialty built operating room. Long term use of the antiplatelet inhibitor, clopidogrel, to be taken by patients in this study, was proven to significantly reduce the risk of adverse ischemic events after percutaneous coronary interventions (Steinhubl, 2002). In addition, the application of Bivalirudin (Direct Thrombin Inhibitor) will be assessed in this integrated myocardial revascularization scenario. The many attractive aspects of robotic hybrid bypass include the avoidance of the procedural phases (arrested heart, blood transfusion, median sternotomy and cardiopulmonary bypass) of on-pump CABG. Robotic LIMA to LAD bypass and stenting in the same procedure will allow cardiac surgeons and cardiologists to work together to help patients obtain safe and effective coronary artery revascularization.

Inclusion criteria

• Patients with class A or B1 low risk coronary artery lesion as defined by TIMI

Exclusion criteria

• Contraindications to PCI which include:

Occluded coronary vessels, PVD, Unable to achieve access, Fresh thrombus, Vessels <1.5mm

• Contraindications to Robotic Surgery which include:

Buried LAD, Unable to tolerate single lung ventilation, Inability to undergo beating heart surgery, Previous surgery of the left chest cavity, Lack of intrathoracic work space, Patients requiring emergency surgery,

The following patients are also excluded:

Patients with coagulation disorders; inability to tolerate GIIb/III inhibitors, Patients with ventricular arrhythmias, Patients with severe non-cardiac conditions with poor prognosis, Patients with a BMI >40, Patients with an ejection fraction of <30%, Patients with chronic renal insufficiency and creatinine >200umol/L, Patients who are >85 years of age, Patients participating in any other investigational device or study drug, Patients who have had previous thoracic surgery, Patients who have a pre-op intra-aortic balloon pump, Patients who are not able to follow the protocol requirements, Patients undergoing concomitant surgery; CABG + Valve surgery