Effects of percutaneous transluminal angioplasty on muscle BOLD-MRI in patients with peripheral arterial occlusive disease: preliminary results

The purpose was to evaluate the effect of percutaneous transluminal angioplasty (PTA) of the superficial femoral artery (SFA) on the blood oxygenation level-dependent (BOLD) signal change in the calf musculature of patients with intermittent claudication. Ten patients (mean age, 63.4+/-11.6 years) with symptomatic peripheral arterial occlusive disease (PAOD) caused by SFA stenoses were investigated before and after PTA. Patients underwent BOLD-MRI 1 day before and 6 weeks after PTA. A T2*-weighted single-shot multi-echo echo-planar MR-imaging technique was applied. The BOLD measurements were acquired at mid-calf level during reactive hyperaemia at 1.5 T. This transient hyperperfusion of the muscle tissue was provoked by suprasystolic cuff compression. Key parameters describing the BOLD signal curve included maximum T2* (T2*(max)), time-to-peak to reach T2*(max) (TTP) and T2* end value (EV) after 600 s of hyperemia. Paired t-tests were applied for statistic comparison. Between baseline and post-PTA, T2*(max) increased from 11.1+/-3.6% to 12.3+/-3.8% (p=0.51), TTP decreased from 48.5+/-20.8 s to 35.3+/-11.6 s (p=0.11) and EV decreased from 6.1+/-6.4% to 5.0+/-4.2% (p=0.69). In conclusion, BOLD-MRI reveals changes of the key parameters T2*(max), TTP, and EV after successful PTA of the calf muscles during reactive hyperaemia.