Closed-Loop Extracorporeal Vascular Cleaning by Staged Chemical Dissolution

A closed-loop extracorporeal system for the removal of atherosclerotic plaque from accessible vascular segments by targeted chemical dissolution in a blood-free environment is proposed. The target segment is isolated by balloon occlusion, drained of blood, and connected to an external bypass that maintains distal perfusion. With the treatment zone converted to a sealed saline chamber, concentrated chemical agents, each targeting a specific plaque component, dissolve the atheroma in situ: ethylenediaminetetraacetic acid (EDTA) for calcified deposits, surfactants for the lipid-rich necrotic core, and collagenase for the fibrous cap. The agents are cycled iteratively to penetrate layered plaque, and dissolved material is flushed out under alternating unidirectional flow, with real-time effluent chemistry providing both treatment endpoint and quantitative plaque composition without imaging. The access geometry uses n+1 balloon catheters to isolate arbitrary vessel topologies, from straight segments to bifurcations and higher-order branch points. An iterative protocol interleaves gentle cleaning sessions with pharmacological lipid and calcium mobilization, progressively draining plaque burden from inaccessible microvascular sites toward accessible ones. Six testable predictions are specified for validation in a porcine atherosclerosis model.