In vitro evaluation of the distribution of blood flow within a canine bipedicled latissimus dorsi muscle flap

Abstract

Objective - To identify the predominant perforating artery in the canine latissimus dorsi muscle and demonstrate that perfusion of the predominant perforating artery improves blood flow in segments of the latissimus dorsi muscle that are located distally from the thoracodorsal artery. Sample Population - Latissimus dorsi muscles dissected from 7 dogs. Procedures - Colored microspheres were used to determine the degree of perfusion of the latissimus dorsi muscle via the thoracodorsal artery, predominant perforating artery, or the thoracodorsal artery and predominant perforating artery together. The latissimus dorsi muscle was divided into 4 proximal to distal segments relative to the thoracodorsal artery (segments A, B, C, and D, respectively). Results - The perforating artery, located at the level of the fifth intercostal space, predominantly supplied perfusion to segments B, C, and D. The number of microspheres received by segment C was significantly higher when the thoracodorsal artery and perforating artery were used for muscle perfusion (181.40 ± 44.90 microspheres/300 g of tissue for every 3,000 spheres injected), compared with use of the thoracodorsal artery alone (60.00 ± 13.70 microspheres/300 g of tissue for every 3,000 spheres injected). Conclusions and Clinical Relevance - Blood flow via the predominant perforating artery improves perfusion to the middle part of the latissimus dorsi muscle in dogs. A bipedicled latissimus dorsi muscle flap would provide a healthier muscle for cardiac assist in the treatment of dilated cardiomyopathy in dogs.