Objective: To evaluate regional, remote, and global effects of percutaneous transluminal septal myocardial ablation (PTSMA) in hypertrophic obstructive cardiomyopathy (HOCM) using magnetic resonance (MR) imaging.
Methods: Twenty-one patients with HOCM underwent cine and delayed contrast-enhanced MR imaging. The regional effects of ablated myocardium as well as remote and global effects of PTSMA were assessed.
Results: The ablated interventricular septal myocardium was hyperenhanced and thinned after successful PTSMA. Decreases in posterior wall thickness and myocardial mass were observed more than 12 weeks after PTSMA. Decreases in posterior wall thickness, myocardial mass, and left atrial diameter were observed in patients without myocardial hyperenhancement before PTSMA. Neither reduction nor increase in hyperenhancing myocardium, except for the ablated myocardium, was observed after PTSMA.
Conclusions: Cardiac MR imaging showed regional, remote, and global effects of PTSMA on the myocardium in HOCM and might indicate patients with a good global response to PTSMA.