Stroke after coronary artery bypass grafting. Is there place for a stroke-risk stratification model?

Preoperative carotid screening is common in the prevention of perioperative stroke. The authors describe our experience with selective screening of patients with a recent (<1 year) neurological event. Because many variables are related with the development of perioperative stroke we additionally evaluate the value of a stroke-risk stratification model.

Of 1 442 isolated myocardial revascularizations performed between January 2002 and December 2005, 118 patients had a history of preoperative stroke. Twenty-four patients had a recent stroke. In 5/24 patients duplex revealed significant stenosis of the internal carotid artery, which was treated prophylactically.

Eleven patients (0.83%) developed a perioperative stroke. Three patients recovered completely during hospital stay, three died related to their stroke. Of the other 94 patients with a history of stroke, 5 had a stroke, none of them had a significant stenosis of the carotid artery. Of the 1,224 patients without a history of stroke, 6 developed a perioperative stroke. Three of them had a significant carotid artery stenosis, however in two patients stroke deficit was on the ipsilateral side and the third patient had a transient ischemic attack. All eleven patients had a calculated stroke risk of 3 or higher corresponding with a expected risk of at least 0.9%.

With the used protocol, in the described patient population, perioperative stroke incidence is low. on the other hand, the complexity of the mechanism of perioperative stroke is confirmed and the use of a stroke-risk stratification model seems us justified for a better identification of patients at risk.