Conceptual Framework of Collateral-promoting Therapy for Coronary Artery Disease

Human coronary collateral circulation (CCC) serves as an alternative blood-conveying circuit to the ischaemic myocardium. Functional potentiation of CCC is considered as a therapeutic approach in patients with intractable angina for whom revascularisation procedures such as percutaneous coronary intervention and coronary artery bypass graft surgery are not indicated. Augmentation of CCC is established by collateral recruitment and growth. Nitrates and sarpogrelate are representative drugs that enhance collateral recruitment. Exercise, enhanced external counterpulsation and whole-body periodic acceleration accelerate and potentiate collateral growth via increased mechanical stress at pre-existent collateral arterioles. Granulocyte macrophage colony-stimulating factor and heparin favourably modulate the cascade of coronary collateral growth. Further experimental and clinical studies will be needed to create more sophisticated coronary collateral-promoting therapies.