Acute Presentation of Bioprosthetic Mitral Valve Thrombosis in a Patient on Venoarterial Extracorporeal Membranous Oxygenation.

The management of patients presenting with bioprosthetic valve thrombosis presents a major clinical challenge from a diagnostic and management standpoint. This patient population becomes especially challenging to manage when presenting with cardiogenic shock and additional risks for bleeding. In this clinical conference, the authors present the case of a 64-year-old male who developed intraoperative bioprosthetic mitral valve thrombosis and cardiogenic shock necessitating support with venoarterial extracorporeal membrane oxygenation. The discussion focuses on the diagnostic challenges with transesophageal echocardiography and the difficulty in determining the proper approach to systemic anticoagulation.

Anesthetic Considerations for Aortic Arch Stenting.

With advances in modern day imaging techniques for the aorta, there has been an increasing incidence of vascular diseases involving the aortic arch. Historically, the only treatment option for arch disease has been open arch replacement under circulatory arrest conditions with or without selective cerebral perfusion. However, this open procedure has significant morbidity and mortality, especially in elderly patients with multiple comorbidities. To potentially mitigate the risks associated with open replacement, endovascular arch repair has gained momentum as an alternative treatment option. Currently, aortic arch stenting is being trialed in multiple international medical centers across Europe and the United States. The outcomes data available thus far are promising, which suggest that there likely will be an increase in patients being referred for aortic arch stenting procedures in the future. In this emerging technology review, multiple aspects of the aortic arch stenting procedure are discussed including the currently available endovascular arch devices, the unique surgical and anesthetic considerations for arch stent implantation, and the early outcomes data published to date.

Early remodeling of repolarizing K+ currents in the αMHC403/+ mouse model of familial hypertrophic cardiomyopathy.

Familial hypertrophic cardiomyopathy (HCM), linked to mutations in myosin, myosin-binding proteins and other sarcolemmal proteins, is associated with increased risk of life threatening ventricular arrhythmias, and a number of animal models have been developed to facilitate analysis of disease progression and mechanisms. In the experiments here, we use the αMHC403/+ mouse line in which one αMHC allele harbors a common HCM mutation (in ßMHC, Arg403 Gln). Here, we demonstrate marked prolongation of QT intervals in young adult (10-12week) male αMHC403/+ mice, well in advance of the onset of measurable left ventricular hypertrophy. Electrophysiological recordings from myocytes isolated from the interventricular septum of these animals revealed significantly (P<0.001) lower peak repolarizing voltage-gated K+ (Kv) current (IK,peak) amplitudes, compared with cells isolated from wild type (WT) littermate controls. Analysis of Kv current waveforms revealed that the amplitudes of the inactivating components of the total outward Kv current, Ito,f, Ito,s and IK,slow, were significantly lower in αMHC403/+, compared with WT, septum cells, whereas Iss amplitudes were similar. The amplitudes/densities of IK,peak and IK,slow were also lower in αMHC403/+, compared with WT, LV wall and LV apex myocytes, whereas Ito,f was attenuated in αMHC403/+ LV wall, but not LV apex, cells. These regional differences in the remodeling of repolarizing Kv currents in the αMHC403/+ mice would be expected to increase the dispersion of ventricular repolarization and be proarrhythmic. Quantitative RT-PCR analysis revealed reductions in the expression of transcripts encoding several K+ channel subunits in the interventricular septum, LV free wall and LV apex of (10-12week) αMHC403/+ mice, although this transcriptional remodeling was not correlated with the observed decreases in K+ current amplitudes.

Liver Transplantation Followed by Renal Transplantation on Extracorporeal Membrane Oxygenation: A Case Report.

We report the case of a 68-year-old woman with end-stage liver disease and end-stage renal disease scheduled for simultaneous liver and kidney transplant. Intraoperatively, she became hemodynamically unstable during her liver transplant surgery, and her renal transplant had to be postponed. On the following day, she required extracorporeal membrane oxygenation and ABIOMED Impella support for managing her severe cardiovascular decompensation. At the same time, the renal transplant was conducted to use the donor kidney already allocated for this patient. The patient was successfully managed postoperatively in the cardiothoracic intensive care unit and was discharged after 2 months. This case is unique because there are no similar cases previously reported in which renal transplantation was performed with extracorporeal membrane oxygenation and Impella support following cardiogenic shock after a liver transplant.