Department of Medical Biophysics, University of Toronto, Canada; Sunnybrook Research Institute, Sunnybrook Health Sciences Centre, Toronto, Canada.
Ultrasonics. 2014 Jan;54(1):20-4. doi: 10.1016/j.ultras.2013.07.014. Epub 2013 Jul 29.
Arterial chronic total occlusions (CTOs) pose considerable challenges for percutaneous interventions, due primarily to the presence of stiff proximal fibrous caps (PFCs) which act as a barrier to the penetration of guide wires. A new approach under development for improving the success rate of guide wire crossing in CTOs is to employ collagenase to degrade the mechanical integrity of the PFCs. This has been shown to be feasible in preclinical work and in a Phase 1 clinical trial. In a recent study we demonstrated using ex vivo experimental CTO specimens that ultrasound-stimulated microbubbles (USMBs) could potentiate the effects of collagenase and result in increased mechanical degradation of the PFCs of CTOs. Here we report the results of the first in vivo study examining the feasibility of this approach, which demonstrates that the force required to puncture through the PFCs of CTOs is reduced with combined USMB+collagenase treatments relative to collagenase only treatments. This approach has the potential to further improve the efficacy of the emerging technique of collagenase facilitation of percutaneous interventions for CTO.
动脉慢性完全闭塞（CTO）给经皮介入治疗带来了相当大的挑战，主要是由于存在坚硬的近端纤维帽（PFC），它是导丝穿透的障碍。为了提高 CTO 中导丝穿越的成功率，正在开发一种新的方法，即使用胶原酶来降解 PFC 的机械完整性。这在临床前工作和 1 期临床试验中已经证明是可行的。在最近的一项研究中，我们使用离体实验性 CTO 标本证明，超声刺激微泡（USMB）可以增强胶原酶的作用，并导致 CTO 的 PFC 机械降解增加。在这里，我们报告了首次体内研究的结果，该研究检查了这种方法的可行性，结果表明，与单独使用胶原酶治疗相比，联合使用 USMB+胶原酶治疗可降低穿透 CTO 的 PFC 所需的力。这种方法有可能进一步提高胶原酶促进经皮介入治疗 CTO 这一新兴技术的疗效。
