Balloon Pulmonary Angioplasty for Chronic Thromboembolic Pulmonary Hypertension.

Chronic thromboembolic pulmonary hypertension (CTEPH) is a potentially lethal outcome of pulmonary embolism. Balloon pulmonary angioplasty (BPA) is aimed at improving pulmonary perfusion and pulmonary hemodynamics and has gained a lot of interest recently in patients either unsuitable for or refractory to surgical pulmonary endarterectomy. This article outlines the clinical features and diagnostic criteria, imaging evaluation, current medical and surgical treatment options for CTEPH. BPA is discussed in detail, focusing on the rationale, patient selection, technical details, post-procedural care and outcomes.

Comparison of muscle mass preservation in denervated muscle and transplanted muscle flaps after motor and sensory reinnervation and neurotization.

The gracilis muscle model was used either as a denervated muscle in situ or as a transplanted flap in 273 rats to compare the trophic effects of muscle reinnervation and neurotization using sensory and motor nerves. The average gracilis muscle flap weighed 626 +/- 94 mg at the time of the initial procedure. Experimental muscles were examined 6 months following the procedure. In denervated, nontransplanted muscles, both motor nerve reinnervation and neurotization resulted in significantly preserved muscle mass, averaging 570 +/- 69 and 521 +/- 116 mg, respectively, compared with the denervated control average of 178 +/- 22 mg (p < 0.05). Sensory nerve reinnervation and neurotization produced much smaller trophic effects (p > 0.05). In transplanted gracilis free flaps, however, only direct reinnervation with motor or sensory nerves resulted in improved bulk preservation, with average weights of 313 +/- 83 and 327 +/- 91 mg compared with the control average of 201 +/- 76 mg (p < 0.05). Neither sensory nor motor neurotization was significantly effective in the free-flap model (p > 0.05). These data suggest that transplantation may alter the response of muscle to reinnervation.

A new automated method for detection and recording of animal moving path.

A new electronic system has been developed to trace the location and movement of small animals in an open-field environment. The system, incorporated with a conventional touch panel position sensor (TPPS) and an IBM AT compatible computer, automtically digitizes and records the moving path of the animal. The detection principle of the TPPS is based on the pressure effect. Whenever an animal is put on the TPPS, the location of the animal can be detected. The personal computer system is in corporate to record the locomotion data of the animal. The system described here is shown to be a reliable and accurate tool to record the moving path of an animal. This measurement did not require extra light or other stimuli, and the apparatus is low priced, and simple to build up and user friendly.

Microvascular vein-graft patency in the rat model.

This study establishes a controlled model, to examine the patency rates of simple, arterial and venous anastomoses, compared to vessel repairs performed with 10-mm, size-matched, interpositional, vein grafts in the rat femoral artery and vein. Patency rates in two control groups, consisting of 68 Sprague-Dawley rats in which simple, femoral-vessel repairs were performed, were compared to three experimental groups, consisting of 94 animals in which the femoral vessels were repaired with interpositional vein grafts. No statistically significant difference was found in the patency rates of arterial (p = 0.487) or venous repairs (p = 0.472) in the control groups. Nor was a significant difference found in arterial vein-graft patency (p = 0.560) or venous vein-graft patency (p = 0.862), when compared to the control groups. This study illustrates that, in the controlled laboratory setting, 10-mm, size-matched, interpositional, vein grafts have statistically the same patency rates as simple repairs of the rat femoral artery and vein.

Microvascular vein grafts in the rat cutaneous free-flap model.

This study utilizes the rat free groin-flap model to evaluate the survival of free flaps following revascularization with interpositional vein grafts. One hundred and fifty-three Sprague-Dawley rats were divided into a control group in which the groin flap was revascularized by simple end-to-end anastomosis, and three experimental groups revascularized with 10-mm, size-matched, interpositional, vein grafts to the femoral artery (Experimental Group 1), to the femoral vein (Experimental Group 2), and to both arterial and venous femoral vessels (Experimental Group 3). No statistically significant difference was noted in survival rates, when the experimental groups were compared to the control group (p1 = 0.619, p2 = 0.677, p3 = 0.666). As demonstrated by this study, free-tissue transfers in the rat, utilizing 10-mm, interpositional, vein grafts that are size-matched, and performed in a controlled laboratory setting, have the same survival rates as those revascularized by primary arterial and venous repairs.

Pectoralis major muscle free flap in rat model.

The rat pectoralis muscle can serve as a vascularized, innervated muscle flap model. The muscle, consisting of superficialis and profundus portions, is supplied by separate neurovascular systems. The vessels to pectoralis profundus (averaging 0.3 mm in diameter) can be taken in continuity with the axillary vessels (averaging 11 mm in diameter), which are used for transplantation. The profundus portion of muscle weighed an average of 1.8 g, and the average pedicle length was 0.9 cm. Nine of 11 transplanted muscles were viable, with intact circulation at 72 hours. An example of muscle transplantation for tissue defect coverage was attempted. The pectoralis profundus transplant was technically reliable, and the muscle bulk and contour could allow biochemical and functional studies.