Preoperative noncontrast chest computed tomography identifies potential aortic emboli

Intraoperative epiaortic scanning identifies aortic atheroma. Avoiding atheroma manipulation reduces cerebral vascular accidents (CVA). Unfortunately, epiaortic scanning can only be performed after the time of sternotomy. We sought to determine whether (1) preoperative noncontrast chest computed tomography (CT) identifies areas of aorta at risk for embolization in high-risk patients, and (2) operative strategies designed at the reduction of aortic manipulation of these areas can reduce permanent strokes.

The rate of permanent strokes was examined at a single institution between two time periods using the chi2 method. From January 2002 through June 2003 (pre-CT) 230 patients underwent elective cardiac procedures. All patients received routine intraoperative transesophageal echocardiography but only selective epiaortic scanning. From July 2003 through December 2005 (post-CT), 273 patients underwent cardiac operations and 114 patients at high risk for a stroke (history of CVA or transient ischemic attack, peripheral vascular disease, end-stage renal disease, age >70 years old or calcifications on cardiac catheterization) also received a preoperative noncontrast chest CT.

In the pre-CT period, 7 patients received epiaortic scans that resulted in a change in operative strategy in only 1 patient. In the post-CT period, the 114 CT scans identified 20 patients with significant calcifications in the ascending aorta. Operative strategy was altered in 19 patients, including 12 axillary artery cannulations, four off-pump, no-touch aorta coronary bypasses, and three ascending aortic replacements. The CVA rate was 3.04% in the pre-CT period and 0.73% in the post-CT period (p = 0.05).

Aggressive screening and avoidance of ascending aortic atheroma reduces stroke. Preoperative CT scans in patients at high risk may help identify aortic areas at risk before entering the operating room, lead to more thorough screening in the operating room, and result in a more aggressive strategy to avoid calcified areas.