Perioperative Impella 5.5 Support for Surgical Aortic Valve Replacement: Pull Back/Push Through Technique, Safeguards, and Pitfalls.

In patients undergoing aortic valve surgery, preoperative reduced left ventricular ejection fraction is not uncommon and is associated with poor outcomes. Mechanical circulatory support (MCS) may be preemptively used in patients presenting with high periprocedural risk. The Impella 5.5 is a percutaneous left ventricular assist device that has been increasingly used in various cardiac surgeries. In this article, we present a step-by-step guide, safeguards, and pitfalls on how to replace the aortic valve and preserve this transaortic MCS device for postoperative support in patients with concomitant aortic valve pathology and left ventricular dysfunction.

An Egr-1 master switch for arteriogenesis: studies in Egr-1 homozygous negative and wild-type animals.

BACKGROUND: Arteriogenesis has been implicated as an important biologic response to acute vascular occlusion. The early growth response 1 (Egr-1) gene encodes an immediate-early response transcription factor that is upregulated by changes in vascular strain and that in turn upregulates a number of putative angiogenic and arteriogenic growth factors. We therefore hypothesized that early growth response 1 might be a critical arteriogenic messenger that induces revascularization in the setting of acute vascular occlusions. METHODS: Wild-type or Egr-1-/- (null) C57 BL mice, or Sprague-Dawley rats, underwent unilateral iliofemoral artery excision and subsequent analyses for angiogenesis and arteriogenesis through cell-specific immunohistochemistry. Rats were also administered an adenoviral vector encoding for Egr-1 (AdEgr group), noncoding vectors (AdNull group), or saline, after which these animals were assessed by means of serial laser Doppler perfusion imaging and morphologic examination of rat foot-pad ischemic lesions. RESULTS: Egr-1 wild-type mice demonstrated an equivalent number of capillaries but a greater number of arterioles following excision versus Egr-1 null mice. AdEgr group rats demonstrated greater distal perfusion from 7 to 21 days after excision compared with control animals (P < .02), which approximated normal perfusion at 21 days after excision. AdEgr group rats also demonstrated greater arteriolar density and less severe ischemic foot-pad lesions than control animals. CONCLUSION: These data suggest the importance of Egr-1 as a critical and potentially therapeutic mediator of revascularization after vascular occlusion and implicate arteriogenesis (collateral vessel formation) as a critical component of this process.