[1009] Cardiovascular and Hemodynamic Propulsion Research

In the Hemodynamic Propulsion Laboratory Charles Hahn the group of cardiovascular research and hemodynamic propulsion supported by the collaborators of cardiovascular surgery department have developed an integrative platform that allows to simulate the of flow and pressure mechanisms under near-real pulsatile conditions replicating the cardiac cycle. The four main research axes of the group are largely based on this platform:

The first axis deals with the topic of heart failure, the second axis treats structural heart disease and valvulopathies, the third axis challenges hemodynamics and flow modeling and the fourth axis is used to develop and optimize new therapeutic devices.

In addition to these four vertical research axes, there are four horizontal platforms: "cellular and tissue research platform", a pulsatile organ perfusion research platform, a pulsatile circuit research platform and finally an intravascular and intracardiac imaging research platform.

CARDIAC INSUFFICIENCY

Focuses on the issues of myocardial ischemia and reperfusion injury induced cardioplegic arrest as well as on the development and testing of new mechanical devices such as circulatory assistance or ventricular reduction devices for new or expanded indications in the field of heart failure. Overview of research projects:

  • Development of a left ventricular assist device to be implanted through minimal invasive access to the left ventricular apex with ventriculo-aortic intra-cardiac propulsion.
  • Evaluation of the vascular wall impact of new therapeutic agents such as calcium sensitizers or adenosine receptor blockers and modulators of endothelin, vasopressin or cytokine in organ bath conditions.
  • Repair and regenerate damaged and dysfunctional myocardial tissue through cell therapy.
  • Development a novel left heart discharge catheter during temporary mechanical heart support.

STRUCTURAL CARDIOPATHY AND VALVULOPATHY

Works on the anatomo-pathology aspect ie cardiac functionality. A multitude of questions with respect to the combination of valvulopathy interaction arises in clinical daily life. The effects on cardiac decompensation and on the patients symptoms are only scarcely understood. With a series of research projects this problem is reviewed and examined. A second aspect is the various valvular reconstruction techniques with or without respect for the sub-valvular apparatus and their consequences on the development of heart failure. Overview of research projects:

  • To measure the impact of mitral insufficiency in the presence of aortic stenosis to determine the best treatment strategy.
  • Evaluate the left ventricular variable geometry in functional mitral insufficiency versus the alignment of papillary muscles in regards of left ventricular ejection fraction.
  • Test different techniques such as the direct resection and reconstruction with or without annuloplasty.
  • The use of neo-cordage
  • The approximation of the papillary muscles and the impact of dimensional reduction devices of the left ventricle with respect to the functioning of the leaflets and the interaction on the mitral apparatus.

HEMODYNAMIC RESEARCH AND FLOW MODALIZATION

Discusses the causes of aortic dissection in the dilated aorta compared to the diameter and measures the impact of haemodynamics on ante- and retrograde dissection propagation. Flow phenomena in variable tubular geometries can cause aneurysmal dilatation. Post-stenotic dilation is a good example but it’s presence is variable. Through a series of in vitro experiments the cause-impact effect is examined. Another recurrent and little understood problem is the impact of endo-leaks after impantation of aortic endo-prostheses. The impact of the persistent flow into the residual aneurysm sac by an artery that feeds the aneurysm retrograde in relation to its size and its flow – a so called a type II endoleak. Overview of research projects:

  • The evaluation of dissection mechanisms and their dynamics of distribution by a aortic in vitro model with variable diameter exposed to a multitude of pulsatile hemodynamic conditions.
  • In-vitro modeling of the residual aneurysmal after endo-prosthesis implantation submitted to an endo-leakage type II in a model that allows to vary size, flow and pressure.
  • The analysis of the changes of flow patterns and sheer stresses following variation of angle of the supra-aortic vessels on the aortic arch and simulation and measure of compliance changes in the aortic arch as well a generation of non-laminar flow.
  • Visualization of transaortal flows in aortic valvular stenosis in the context of tricuspid and bicuspid valves and after reconstruction of the aortic valve and measurement of the impact on dilation downstream of the lesion.

DEVICES

Endo-cardiac and endovascular therapies show significant growth It is conceivable that the permanent cardiac assistant is implanted quasi-percutaneously as mentioned in position 1.1 with a device that allows to collect the blood in the left ventricle and propels it endo-vascularly through the aortic or pulmonary valve. Other techniques and devices are intended to facilitate an existing endovascular procedure or to improve devices in clinical use. Finally the development of new devices is essential to the progress in cardiovascular medicine. Overview of Research Projects:

  • Development of a novel Left Ventricular Assist Device
  • Development of a prosthesis to exclude aneurysms and dissection of the aortic arch implanted via bi-directional left femoral and left apical access.
  • Development of a facilitator catheter to canulate the contralateral side of a bifurcated aortic prosthesis.
  • Development of a device for closing the left atrial appendix for surgical and endo-cardiac use.
  • Development of wire technologies to allow for a fully percutaneous transapical large caliber access.

Publications of the group