Introduction

Left bundle area pacing (LBP) promises a revolution for treating bradycardia and achieving cardiac resynchronization1–4, but has lower success rates in ischemic cardiomyopathy2,3,5The reasons are not clear but may include difficulty in reaching the left bundle area or stimulating it adequately. For such patients, operators therefore sometimes aim for His bundle pacing accepting the potential for higher capture thresholds and lower amplitude R waves.
The technique for LBP involves deploying the lead through the interventricular septum, which may be scarred in patients in patients with ischemic cardiomyopathy. Late gadolinium enhancement (LGE) on MRI is a reliable way of detecting, localizing and quantifying myocardial scar6,7non-invasively. However, the 3830 SelectSecure lead (Medtronic, Minneapolis, MN) when implanted for LBP is currently not MRI conditional, and therefore post-procedure scanning would be more challenging.
We therefore conducted a systematic protocol of MRI scanning before attempting LBP, to test whether localized late gadolinium enhancement might reveal the mechanism of the difficulties seen in some patients.