Internal mammary artery grafting in patients with smaller body structure.

The results of internal mammary artery grafting in 50 patients with a body surface area less than 1.6 m2 were compared with those in 54 patients with a larger body surface area. Age (58.8 +/- 8.2 versus 54.9 +/- 10.3 years old) and prevalence of female gender (28% versus 4%) were significantly different between the group of patients with a small body surface area and the group with a large body surface area, respectively. However, the prevalence of unstable angina, previous myocardial infarction, extent of coronary artery disease, and preoperative ejection fraction was not significantly different between the two groups. The mean number of distal anastomoses was 3.0 and 2.8, and the mean duration of aortic occlusion was 65.6 +/- 23.0 minutes and 59.5 +/- 21.7 minutes in the small and large body surface area groups, respectively (not significant). The mean free flow rate of the internal mammary artery was 65.6 +/- 16.8 ml/min in the small body surface area group and 78.0 +/- 21.6 ml/min in the large body surface area group (p less than 0.05). The diameters of the anterior descending and the circumflex arteries were significantly smaller in the small body surface area group. Two patients (4%) died within 30 days of operation and one patient died later in the small body surface area group, whereas no death was noted in the large body surface area group (not significant). No significant differences were found in the incidence of aortic balloon pumping, perioperative myocardial infarction, and serious postoperative complications between the two groups. Symptomatic relief was equally good in both groups (92% and 96%). The patency rate of the internal mammary artery was 95% (42/44) in the small body surface area group and 100% (48/48) in the large body surface area group within 1 year, mean 2.3 +/- 2.4 months. In conclusion, internal mammary artery grafting can be performed safely and effectively even in patients with small body structure. Though the blood flow of the internal mammary artery and the size of the coronary arteries were smaller in patients with small body structure, excellent patency of the internal mammary artery graft and satisfactory symptomatic relief can be expected.