Central nervous system damage following surgery using cardiopulmonary bypass--a retrospective analysis of 1386 cases.

In order to determine the incidence and risk of central nervous system damage (CNSD) which accompanies cardiovascular surgery, a retrospective analysis was carried out on 1386 patients who received surgery utilizing cardiopulmonary bypass. CNSD occurred in 32 of the 1386 patients, the total incidence being 2.3 per cent. The major risk factors which led to a high incidence of CNSD were found to be reoperation, thrombus in the left atrium (TLA) and calcification of the ascending aorta (Cal aAo). In the primary surgical series, CNSD was found in only 29 of 1350 patients (2.2 per cent), however, of a total 36 patients who underwent reoperation, 3 (8.3 per cent) patients developed CNSD (p less than 0.05). In a surgical series done on 562 patients with mitral valve disease, the prevalence of CNSD was much higher in patients who suffered TLA than in those who did not, being 4/85 cases (4.7 per cent) vs 11/477 cases (2.3 per cent), respectively. Moreover, a significantly higher incidence of CNSD was noted in patients with Cal aAo, occurring in 6/10 cases (60 per cent) with Cal aAo vs 4/333 cases (1.2 per cent) without Cal aAo (p less than 0.001). The results of this study showed that patients with CNSD, who had received coronary artery bypass surgery and aortic arch replacement tended to follow a poor clinical course, suggesting that atheromatous plaque embolization may be the leading cause of the poor prognosis following CNSD in patients having undergone cardiopulmonary bypass.