ASAIO Journal最新文献

The vortex that forms in the aortic sinus plays a vital role in optimizing blood flow. Disruption of the vortex can result in flow stagnation and activate thrombus formation in the aortic root, especially when aortic valve flow is reduced as during left ventricular assist device (LVAD) support. Our goal in this study was to visualize vortex formation in an experimental model of the aortic root as flow is progressively reduced. A mock circulatory loop that reproduces heart failure hemodynamics was combined with a HeartMate II LVAD and velocity measured in a transparent aortic root with a bioprosthetic valve. The aortic valve sinus vortices are clearly visible as counter-rotating structures in the velocity field at baseline and for all conditions with flow through the aortic valve. As LVAD speed increases, the central jet narrows but the vortices persist, disappearing only when the valve is completely closed. The vortices preserve fluid momentum and generate shear stress along the tissue surfaces which disrupts flow stasis. These features underscore the importance of maintaining "intermittent" aortic valve opening, as recommended for LVAD patients. This study is the first to report vortex formation in the aortic root during LVAD support, providing a motivation for further evaluation.

The intricate management of hemostatic disorders in extracorporeal membrane oxygenation (ECMO) assisted patients poses challenges, particularly when procoagulant administration is necessary. We hereby report the performance of the Nautilus* Smart ECMO Module in three patients with hemostatic disorders. We collected data from ECMO procedures with Nautilus* Smart ECMO Module and analyzed the performance: the operating pressures and resistance of the device in addition to the coagulation status of the patients. During the three procedures, partial pressure oxygen post-oxygenator (paO 2 ) stayed above 100 mm Hg and partial pressure carbon dioxide post-oxygenator (paCO 2 ) did not exceed 45 mm Hg. Membrane FiO 2 (fractional inspired O 2 ) did not exceed 75% and air flow remained within a 1:1 ratio with blood flow in veno-arterial ECMO (V-A) and within 1:2 in veno-venous ECMO (V-V). There was no evidence of excessive operating pressure for the device, with a pressure drop consistently below 28 mm Hg and a maximum peak resistance of 7 Δmm Hg/L/min. The Nautilus* Smart ECMO Module showed good performance in patients with hemostatic disorders despite the implications associated with procoagulant administration.

The impact of cardiac resynchronization therapy (CRT) in patients receiving durable left ventricular assist device (LVAD) implantation remains unclear and there is no consensus regarding postoperative management. We sought to determine the impact of postoperative management of CRT on clinical outcomes following LVAD implantation. A total of 789 patients underwent LVAD implantation at our institution from 2007 to 2022 including 195 patients (24.7%) with preoperative CRT. Patients with preoperative CRT were significantly older and more frequently received an LVAD as destination therapy compared to patients without preoperative CRT. After LVAD implantation, 85 patients had CRT programmed "off" and 74 patients had CRT programmed "on." The risk of mortality was significantly increased amongst patients with preoperative CRT that was turned "on" following LVAD implantation compared to patients with preoperative CRT turned "off" following implant (subdistribution hazard ratio [sdHR] = 1.54; 1.06-2.37 95% confidence interval [CI]; p = 0.036). There was no significant difference between incidence of ventricular arrhythmias in patients with and without postoperative CRT "on" (35.1% vs . 48.2%; p = 0.095). Additional clinical trials are warranted to determine the best CRT programming strategy following LVAD implantation.

The use of cardiac devices, including mechanical circulatory support (MCS), cardiac implantable electronic devices (CIEDs), and pacing wires, has increased and significantly improved survival in patients with severe cardiac failure. However, these devices are frequently associated with acute brain injuries (ABIs) including ischemic strokes, intracranial hemorrhages, seizures, and hypoxic-ischemic brain injury which contribute substantially to morbidity and mortality. Computed tomography (CT) and magnetic resonance imaging (MRI), the standard imaging modalities for ABI diagnosis, can pose significant challenges in this patient population due to the risks associated with patient transportation and the incompatibility of ferromagnetic components of certain cardiac devices with high magnetic field of the MRI. This review discusses the application of Ultralow-field portable MRI (ULF-pMRI), which operates at much lower magnetic field (0.064 T), with the potential to allow safe bedside imaging of critically ill patients. In this review, we detail the clinical studies and research findings defining the safety, feasibility, and diagnostic utility of ULF-pMRI in detecting ABI in the critically ill. We further discuss the potential broader applications of ULF-pMRI, as a standard diagnostic tool for neurocritical care in patients with cardiac devices. The integration of such technology into current practice promises to enhance diagnostic accuracy, improve patient outcomes, and optimize healthcare resources.

Adult patients with congenital heart disease (ACHD) requiring heart transplantation (HT) usually show complex anatomies, posing surgical challenges. Consequently, we analyzed technical aspects and early and long-term outcomes of additional surgical repairs during HT in ACHD. Forty patients were identified (23 males, median age: 38 years, interquartile range [IQR]: 26-50). Of these, 17 (42.5%) required additional surgical repair (7 systemic veins repair, 13 pulmonary arteries repair). These procedures were more associated with univentricular physiology ( p < 0.001) and prior Fontan palliation ( p < 0.001). Eight (20.0%) experienced 30 day mortality. At a median follow-up of 5.6 (IQR: 2.0-11.9) years, 5 (12.5%) patients died. Additional surgical repair did not affect postoperative 30 day and long-term follow-up mortality ( p = 0.451 and p = 0.330, respectively).

The use of an alteplase (Activase) purge solution to address Impella ventricular assist device "thrombosis" or "purge system occlusion" has been mainly documented with earlier generation Impella devices (CP, 2.5, 5.0). Here, we report the use of an alteplase purge solution to manage Impella 5.5 purge system occlusion in a 31-year-old male admitted to the cardiac care unit in cardiogenic shock and listed for a heart transplant. Throughout the purge system occlusion, the patient demonstrated hemodynamic stability and overall pump flow and cardiac output were preserved. Initially, there was a lack of response in purge flow and pressure observed at the lower concentration of alteplase purge solution (0.04 mg/ml), yet after using the alteplase 4 mg/50 ml purge (0.08 mg/ml) solution concentration, a response was seen. No bleeding or hemodynamic complications were observed. In addition, a suggested management workflow and review of the case reports and case series published to date regarding Impella purge system occlusion is included in this article.