Comparison of left internal mammary artery diameter before and after left stellate ganglion block.

ABSTRACT

Aims and Objectives: Left internal mammary artery (LIMA) is the preferred arterial conduit for coronary artery bypass grafting. Various pharmacological agents are known to increase LIMA blood flow. Sympathetic blockade mediated by stellate ganglion block (SGB) has been used to provide vasodilatation in the upper extremities and in the treatment of refractory angina. We investigated effect of left stellate ganglion block (LSGB) on LIMA diameter. Materials and Methods: In 30 diagnosed patients of triple vessel coronary artery disease, LSGB was given under fluoroscopic guidance by C6 transverse process approach using 10 ml of 1% lignocaine. LIMA diameter was measured before and 20 min after the block at 2nd, 3rd, 4th and at 5th rib level. Heart rate (HR), systolic blood pressure (SBP), diastolic blood pressure (DBP) and mean arterial pressure (MAP) were recorded before and 20 min after the block. Results: The LIMA diameter increased significantly at 2nd (2.56 ± 0.39 vs. 2.99 ± 0.40; P < 0.0001), 3rd (2.46 ± 0.38 vs. 2.90 ± 0.40; P < 0.0001), 4th (2.39 ± 0.38 vs. 2.84 ± 0.41; P < 0.0001) and 5th rib level (2.35 ± 0.38 vs. 2.78 ± 0.40; P < 0.0001). No statistically significant change occurred in HR, SBP, DBP and MAP before and 20 min after LSGB. Conclusions: LSGB significantly increased the LIMA diameter. The LSGB can be considered as an alternative to topical and systemic vasodilators for reducing vasospasm of LIMA.