How safe is the port access technique in minimally invasive coronary artery bypass grafting?

BACKGROUND

This study compares conventional coronary artery bypass grafting (CABG) with port access CABG via a left anterior small thoracotomy in patients requiring surgical multivessel revascularization. Clinical, neuropsychological, and angiographic outcomes were studied, as well as parameters of myocardial and cerebral protection. Pathogenicity of cardiopulmonary bypass (CPB) was further evaluated by measuring parameters of peripheral limb ischemia and inflammatory whole-body response.

METHODS

In a prospective randomized study, 40 patients who required multivessel CABG were assigned to either conventional CABG via complete median sternotomy (group A) or port access CABG via minithoracotomy (group B). Control angiograms were performed in group B only. In addition, patients underwent neuropsychological testing after the operation. CK, CK-MB, and Troponin T levels were documented. S-100B protein and neuron-specific enolase (NSE) served to quantify cerebral injury. The terminal complement complex (C5b-9) and myeloperoxidase concentrations were determined to analyze inflammatory whole-body response after CPB.

RESULTS

There was no mortality. One patient suffered a retrograde aortic dissection immediately after onset of CPB, but had an uneventful postoperative course after surgical repair. Troponin T and CK-MB showed no difference between groups. CK and myoglobin were significantly higher in the minimally invasive cohort. Changes in complement activation (C5b-9) and myeloperoxidase during CPB markers of the whole-body inflammatory response were similar in both groups. S-100B concentrations in the port access group were significantly higher, whereas NSE levels were similar in both groups. Both groups did not display any significant difference in neuropsychological testing.

CONCLUSIONS

Minimally invasive multivessel CABG via minithoracotomy using port access technology is feasible and safe. Though prolonged operating and CPB times with significantly higher S-100B concentrations were observed in group B, equivalent myocardial and cerebral protection and similar whole-body inflammatory response were documented.