ABSTRACT
Transcatheter aortic valve replacement (TAVR) is a new, rapidly evolving technology used in severe cases of aortic stenosis. Some TAVR procedures have failed to deliver the prosthetic valve due to challenges. In these cases, it is difficult to pass a bulky prosthesis through a narrowed and calcified aortic valve. Special techniques may be needed in these challenging cases. In our case, the extreme calcification and the horizontal aorta caused the delivery system to hang up on the aortic valve. We used a buddy balloon from the contralateral femoral artery to assist in crossing the native aortic valve.
ABSTRACT
A 63-year-old man was admitted with chest pain after a previous aortic valve replacement. Computed tomographic scan identified a 7-cm pseudoaneurysm of the ascending aorta, and he was referred for repair. At operation, endoaortic occlusion of the aorta was used to arrest the heart and decompress the aorta to facilitate sternal reentry, dissection, and subsequent control. To our knowledge, this technique has not been reported and represents a useful maneuver in this challenging clinical situation.
Subject(s)
Aneurysm, False/therapy , Aortic Aneurysm/therapy , Balloon Occlusion/methods , Aneurysm, False/diagnosis , Aneurysm, False/etiology , Aortic Aneurysm/diagnosis , Aortic Aneurysm/etiology , Heart Valve Prosthesis Implantation/adverse effects , Humans , Male , Middle Aged , Postoperative ComplicationsABSTRACT
BACKGROUND: Severe traumatic injury elicits a neuroendocrine response that activates the sympathetic nervous system. Our previous work suggests that norepinephrine (NE) influences the bone marrow (BM) erythropoietic response. However, the dose-response relationship between NE and erythropoiesis remains unclear. MATERIALS AND METHODS: Two days following chemical sympathectomy with 6-hydroxydopamine (6-OHDA) or injection with saline vehicle (SHAM), male Sprague-Dawley rats were infused continuously with either saline (NS) or increasing doses of NE for 5 d via osmotic pumps. Erythropoiesis was assessed by growth of erythroid progenitor colonies (BFU-E and CFU-E for early and late progenitors, respectively). RESULTS: Following chemical sympathectomy with 6-OHDA, both BFU-E and CFU-E growth is inhibited (42%∗ and 43%∗ versus 100% SHAM, ∗P < 0.05). SHAM rats with continuous infusion of exogenous NE show a clear dose-response inhibition of both BFU-E and CFU-E colony growth. In the 6-OHDA rats, continuous infusion of NE restored BFU-E and CFU-E growth at 10(-8) g/h and 10(-9) g/h, respectively. CONCLUSIONS: Erythroid precursor colony growth is inhibited in sympathectomized rats. In addition, supraphysiologic doses of exogenous NE inhibit normal erythropoiesis in a dose-dependent fashion. Following chemical sympathectomy with 6-OHDA, exogenous NE restores erythropoiesis in a narrow window. Therefore, NE has a complex interaction within the BM and the elevation of NE following traumatic injury impacts BM erythropoietic function.