Stent-based approach for ventricle-to-coronary artery bypass

Area of Science:

• Cardiovascular Surgery
• Biomedical Engineering
• Interventional Cardiology

Background:

• Ventricle-to-coronary artery bypass (VCAB) is an experimental revascularization technique.
• VCAB primarily delivers systolic blood flow to the coronary artery.

Purpose of the Study:

• To develop and evaluate a stent-based procedure (VSTENT) for creating a VCAB.
• To assess the efficacy of VSTENT in preserving myocardial blood flow and function under conditions of coronary artery stenosis and occlusion.

Main Methods:

• A covered stent (VSTENT) was implanted between the left ventricle and the left anterior descending coronary artery (LAD) in a pig model.
• Distal LAD flow, regional myocardial function, and intracoronary pressures were measured during varying degrees of LAD stenosis and complete occlusion.
• The influence of VSTENT positioning and a potential valve-like diastolic mechanism on flow preservation was investigated.

Main Results:

• VSTENT preserved 70±6% of baseline net forward flow and 71±8% of regional myocardial function during 3 hours of LAD occlusion.
• Flow preservation was influenced by VSTENT positioning, with enhanced preservation when a valve-like mechanism was present during diastole.
• Systolic inflow predominated at significant LAD stenosis (>70%), and mean diastolic intracoronary pressure correlated linearly with net flow (r=0.88, P<0.001).

Conclusions:

• The stent-based ventricle-to-coronary artery bypass (VSTENT) is a feasible procedure.
• VSTENT successfully preserved significant myocardial blood flow and function during complete LAD occlusion.
• The diastolic valve-like mechanism created by VSTENT positioning and favorable interaction with residual diastolic flow in stenotic arteries contribute to favorable outcomes.