DUPLEX ULTRASNOGRAPHIC EVALUATION OF RADIAL AND ULNAR ARTERIES PRIOR TO RADIAL ARTERY HARVEST IN CORONARY ARTERY BYPASS GRAFTING

Purpose: Use of radial artery (RA) in coronary artery bypass grafting (CABG) became the most preferable graft choice after internal mammary artery. Purpose of the study was to evaluate by duplex-US the caliber and patency of RA and ulnar artery (UA), presence and intensity of atherosclerotic changes, and to determine the adequacy of collateral forearm circulation in pts scheduled for CABG procedure.

Methods and Materials: RA and UA of 343 pts that were candidates for CABG surgery were examined using Logiq 9 scanner (G.E.)with 9–14MHz linear transducer. Vessel size and PSV were measured. Presence of atherosclerotic changes and their degree (mild, moderate, severe) were assessed. To evaluate collateral circulation after RA harvest two functional tests were performed: (1) radial artery compression test (RACT) with measurements of PSV in UA during RA compression – increase of UA PSV >20% was considered normal; (2) testing of flow in superficial palmar branch of RA – complete absence of flow during RACT was considered abnormal. 274 patients were male, 69 female, age range 36–83 (median 63yrs). Descriptive statistics, parametric and nonparametric tests were used for analysis of observed differences. We did not recommend harvesting of RA in cases of diffuse and severe atherosclerotic changes, of RA hypoplasia, or of abnormal functional tests.

Results: The diameters of RA and UA were significantly larger in males (p<0.01) and RA had larger diameter compared to UA in 66% of pts on the right side, and 60% of pts on the left side. Hypoplasia (diameter<2mm) was present in 4.6% of examined vessels. Abnormal RACT with insufficient PSV increase in UA was observed in 7.5% of pts. Abnormal superficial branch of RA test was observed in 7.9% of pts. Atherosclerotic changes were present in 33% and 27% of pts, severe changes being more pronounced in UA than in RA (7.3% vs. 3.1%; p<0.01). In 6 pts (<2%) stenosis >50% was noted in UA or RA. In 7 pts subclavian steal syndrom was diagnosed. In 10.5% of pts RA harvest on one or both sides was not recommended. In 107 patients in whom RA was harvested no cases of acute postoperative hand ischemia occured and no motoric and/or sensory deficites that would affect normal function were observed in the follow-up period of 1 months to 2 years.

Conclusions: Duplex US is suitable for preoperative evaluation of forearm arteries prior to RA harvesting for CABG. It provides useful information about anatomy and degree of atherosclerotic changes of forearm arteries, and about the sufficiency of collateral forearm circulation after RA harvesting. US can identify arteries that are not suitable for CABG in approximately 10% of pts, and can thus alter approach to CABG.