Abstract
AIMS: The aim of this study was to determine whether revascularisation of an infarct-related artery chronic total occlusion (IRA-CTO) has a modulatory effect on myocardial scar composition. METHODS AND RESULTS: This is a unique, first-time report of three consecutive patients presenting with myocardial scar-related recurrent ventricular tachycardia (rVT) on a background of ischaemic cardiomyopathy. Electro-anatomic mapping of the left ventricular endocardium was performed before and immediately after IRA-CTO percutaneous coronary intervention (PCI) to assess for changes in scar composition and size. There were substantial percentage reductions in the low voltage area of scar compared to baseline after IRA-CTO PCI (Patient 1: -12.8%, Patient 2: -27.0%, and Patient 3: -15.3%). Interval remapping ≥6 months after the index procedure demonstrated extensive net reductions in all areas of myocardial scar (Patient 1: dense scar =-7.5%, border zone scar =-54.9%, low voltage area =-32.7%, and Patient 2: dense scar =-38.6%, border zone scar =-59.6%, low voltage area =-51.7%). Patient 3 declined interval remapping but has remained free of rVT at one-year follow-up. CONCLUSIONS: IRA-CTO PCI may positively modify the size and composition of myocardial scar associated with rVT in the context of ischaemic cardiomyopathy.