Cardio-Obstetric Shock: Mechanical Circulatory Support as a Bridge to Pregnancy Viability.

Cardiogenic shock in pregnancy is rare but is associated with significant morbidity and mortality. Timely recognition with multidisciplinary management is necessary for optimal maternal and fetal outcomes. Here we present a case of cardiogenic shock in the antepartum period managed with mechanical circulatory support as a bridge to pregnancy viability.

Normalizing arterial blood pressure in patients with aortic stenosis does not prevent grading discrepancies between pre-cardiopulmonary bypass transesophageal echocardiography and transthoracic echocardiography.

Background: Aortic stenosis (AS) grading discrepancies exist between pre-cardiopulmonary (pre-CPB) transesophageal echocardiography (TEE) and preoperative transthoracic echocardiography (TTE). Prior studies have not systematically controlled blood pressure.

Aims: We hypothesized that normalizing arterial blood pressure during pre-CPB TEE for patients undergoing valve replacement for AS would result in equivalent grading measurements when compared to TTE.

Asymptomatic Severe Aortic Stenosis and Noncardiac Surgery.

The patient with severe asymptomatic aortic stenosis presenting for elective noncardiac surgery poses a unique challenge. These patients are not traditionally offered surgical aortic valve replacement or transcatheter aortic valve replacement given their lack of symptoms; however, they are at increased risk for postsurgical complications given the severity of their aortic stenosis. The decision to proceed with elective noncardiac surgery should be based on individual and surgical risk factors.

Use of three-dimensional transesophageal echocardiography to evaluate mitral valve morphology for risk stratification prior to mitral valvuloplasty.

Unlabelled: Mitral stenosis is often managed percutaneously with an interventional procedure such as balloon commissurotomy. Although this often results in an increased mitral valve area and improved clinical symptoms, this procedure is not benign and may have serious complications including the development of hemodynamically significant mitral valve regurgitation. Multiple scoring systems have been developed to attempt to risk stratify these patients prior to their procedure.

Finite Element Study of a Lumbar Intervertebral Disc Nucleus Replacement Device.

Nucleus replacement technologies are a minimally invasive alternative to spinal fusion and total disc replacement that have the potential to reduce pain and restore motion for patients with degenerative disc disease. Finite element modeling can be used to determine the biomechanics associated with nucleus replacement technologies. The current study focuses on a new nucleus replacement device designed as a conforming silicone implant with an internal void.

Development and validation of a statistical shape modeling-based finite element model of the cervical spine under low-level multiple direction loading conditions.

Cervical spinal injuries are a significant concern in all trauma injuries. Recent military conflicts have demonstrated the substantial risk of spinal injury for the modern warfighter. Finite element models used to investigate injury mechanisms often fail to examine the effects of variation in geometry or material properties on mechanical behavior.

Implementation and validation of probabilistic models of the anterior longitudinal ligament and posterior longitudinal ligament of the cervical spine.

The objective of this investigation was to develop probabilistic finite element (FE) models of the anterior longitudinal ligament (ALL) and posterior longitudinal ligament (PLL) of the cervical spine that incorporate the natural variability of biological specimens. In addition to the model development, a rigorous validation methodology was developed to quantify model performance. Experimental data for the geometry and dynamic properties of the ALL and PLL were used to create probabilistic FE models capable of predicting not only the mean dynamic relaxation response but also the observed experimental variation of that response.

Dendritic processes of osteocytes are mechanotransducers that induce the opening of hemichannels.

Osteocytes with long dendritic processes are known to sense mechanical loading, which is essential for bone remodeling. There has been a long-standing debate with regard to which part(s) of osteocyte, the cell body versus the dendritic process, acts as a mechanical sensor. To address this question experimentally, we used a transwell filter system that differentiates the cell body from the dendritic processes.