An unusual cause for coronary bypass graft stenosis

Abstract

We report a case of a 61-year-old male who presented for diagnostic angiography for further investigation of poorly controlled angina. This patient had a significant cardiovascular disease history including coronary artery bypass grafting of the LIMA to LAD, SVG to OM1, SVG to D2 and SVG to PDA 21 years prior. Over the subsequent years he required percutaneous coronary intervention (PCI) to the SVG-OM twice and once to the SVG-PDA. The last angiogram in 2011 resulted in PCI to the LIMA-LAD. His remaining past medical history comprised hypertension, hyperlipidaemia and a significant smoking habit. The native vessel study, via the femoral approach, was unchanged from the prior angiogram with diffuse disease requiring no intervention. The graft study demonstrated a 75% proximal in-stent re-stenosis in the SVG-OM that was successfully managed with balloon angioplasty. On engaging the SVGD2, a 70% proximal short stenosis (figure 1a) was present that resolved after wiring and injection of 150mcg of glyceryl trinitrate (figure 1b). This lesion represented a vein graft spasm. The procedure was completed without further complications and the patient was discharged on dual antiplatelet therapy for 12 months with aggressive risk factor modification. This case highlighted the potential for vein graft spasm during coronary angiography of grafts. The usual management of these events involves the use of nitrates with relative success. Vein graft spasm is very unusual as there is no muscular layer of vein graft. The key learning point is that the vein graft spasm does occur and recognise it. (Figure presented).<br />