Preservation of von Willebrand Factor Activity With the ModulHeart Device

Association of Left Ventricular Size on Outcomes in Patients With Left Main Coronary Artery Myocardial Infarction Complicated by Cardiogenic Shock

BACKGROUND

Cardiogenic shock in left main coronary artery acute myocardial infarction patients has high mortality rates. This study investigates the association between left ventricular size and outcomes in these patients treated with veno-arterial extracorporeal membrane oxygenation.

METHODS

This retrospective single-center study examined patients who underwent percutaneous coronary intervention for left main coronary artery acute myocardial infarction and developed refractory cardiogenic shock between April 2013 and August 2021. Baseline characteristics and echocardiographic assessments were conducted 24-48 h after veno-arterial extracorporeal membrane oxygenation initiation. Patients were divided into two groups: small left ventricle (S-group, ≤ 23 mm/m2 for males and ≤ 26 mm/m2 for females, n = 11) and regular left ventricle (R-group, n = 22). The primary outcome was a 1-year survival. The analysis included survival and adjusted multivariate Cox proportional hazards modeling.

RESULTS

The S-group showed a significantly higher mortality rate during support (63.6% vs. 4.5%, p = 0.001). In the unadjusted survival analysis, the 1-year survival rate was significantly lower in the S-group (9.0% [95% CI, 1.4-58.9] vs. 59.1% [95% CI, 41.7-83.6], p < 0.01). After adjusting for confounders, multivariate Cox analysis identified a small left ventricle (adjusted HR 8.38, 95% CI 2.33-30.16, p = 0.001), advanced age (per 10-year increase, adjusted HR 2.35, 95% CI 1.39-3.98, p = 0.001), and lower baseline left ventricular ejection fraction (per 10% decrease, adjusted HR 0.48, 95% CI 0.26-0.88, p = 0.018) as significant predictors of 1-year all-cause mortality.

CONCLUSIONS

In patients with severe cardiogenic shock following left main coronary artery acute myocardial infarction requiring veno-arterial extracorporeal membrane oxygenation, a small left ventricle is associated with a poor prognosis.

Numerical investigation of the flow induced by a transcatheter intra-aortic entrainment pump

This study evaluates the fluid dynamics inside and outside transcatheter blood pump positioned in the aorta. We focus on the pump's impact on blood component damage and arterial wall stress. CFD simulations were performed for rotational speeds ranging from 6000 to 15000 rpm, with a blood flow rate of 1.6 L/min. Results show that significant blood damage may occur at speeds as low as 12000 rpm, and the pump's outflow jet induces elevated wall shear stress, potentially leading to arterial aneurysms. These findings suggest the need for further design improvements to reduce risks when used in prolonged or transplant-related applications.

Organ blood flow assessment with the ModulHeart cardiorenal support device

BACKGROUND

ModulHeart (Puzzle Medical Devices Inc) is a novel percutaneous flow entrainment pump anchored in the descending aorta. The current study evaluates the hemodynamic effect of ModulHeart support and its impact on cerebral, myocardial, and renal blood flow.

METHODS

ModulHeart was implanted in the descending aorta of four healthy calves. A ramp protocol (2000 RPM increments) was performed with the pump operating at five different speeds from 14 000 to 22 000 RPM. For each speed, pressures proximal and distal to the pump, and right heart catheterization measurements were recorded. Stable-isotope labeled microspheres were injected in the left ventricle to evaluate organ perfusion.

RESULTS

Thermodilution cardiac output increased by 23% at 22 000 RPM. Greater pump speeds resulted in greater pump gradients, up to 10 mm Hg in mean arterial pressure at 22 000 RPM, without significant reduction of proximal perfusion pressures. Arterial pulse pressure remained stable at all speeds. ModulHeart was not associated with a reduction in cerebral or myocardial blood flow at any speed. Renal cortical and medullary blood flow increased by up to 50% and 40%, respectively.

CONCLUSION

The ModulHeart device implanted in the descending aorta of healthy calves resulted in significant arterial pressure gradients and preserved pulse pressure. Greater pump speeds translated into greater increases in renal blood flow, with no decrease in cerebral or myocardial perfusion.