Yag. Louagie et al., OPERATION FOR UNSTABLE ANGINA-PECTORIS - FACTORS INFLUENCING ADVERSE IN-HOSPITAL OUTCOME, The Annals of thoracic surgery, 59(5), 1995, pp. 1141-1149
Coronary artery bypass grafting for the treatment of unstable angina i
s still associated with increased operative risk and postoperative mor
bidity. The impact of the extended use of arterial grafts on early res
ults is incompletely defined. In a 7-year period (1986 to 1993), 474 p
atients (average age, 65 years; range, 34 to 85 years) underwent coron
ary artery bypass grafting for the treatment of unstable angina. Sixty
-eight patients were operated on emergently and 406 urgently. They rec
eived an average of 3.0 distal anastomoses (range, 1 to 6). Seventy-ni
ne patients had exclusively venous grafts, 316 had one internal thorac
ic artery graft, 79 had bilateral internal thoracic artery grafts, and
20 had inferior epigastric artery grafts. Sequential internal thoraci
c artery grafting was performed in 70 patients. Redo operations were p
erformed in 26 patients. Thirty-four patients (7.2%) experienced a new
myocardial infarction. Eighty-nine patients (18.8%) had an intraaorti
c balloon pump inserted preoperatively, intraoperatively, or postopera
tively. Eight patients (1.7%) died intraoperatively and 24 patients (5
.1%) died postoperatively. Seventy-seven patients (16.2%) had an adver
se outcome, as shown by the need for an intraaortic balloon pump (intr
aoperatively or postoperatively) or hospital death, or by both. Forty
variables were examined by multivariate analysis for their influence o
n the occurrence of an adverse outcome. Aortic cross-clamp time (p = 0
.0004), transfer from the intensive care unit (p = 0.0023), female sex
(p = 0.0023), operation performed in early years (p = 0.0041), left v
entricular aneurysm (p 0.0068), the number of diseased coronary vessel
s (p = 0.0312), and reoperation (p = 0.0318) were all found to be sign
ificant independent predictors of increased risk. Thus, aortic cross-c
lamp duration remains the main determining factor of postoperative hos
pital outcome, which suggests the need for improved myocardial protect
ion techniques. Outcome was not found to be adversely affected by the
extended use of arterial grafts.