[Emergency stent implantation in the area of extensive muscle bridging of the anterior interventricular ramus after post-interventional dissection].

In a 64-year-old male patient with severe angina pectoris (CCS III) a systolic compression caused by a coronary muscle bridging in the left anterior descending artery could be detected by coronary angiography. Intravascular ultrasound (IVUS) as well as intracoronary Doppler examination showed a significant systolic reduction of the cross-sectional luminal area of 35.9% and a reduced coronary flow velocity ratio (CFVR) of 2.6. Two highly significant stenosis were detected proximal and distal of the muscle bridge. Percutaneous transluminal coronary angioplasty was performed at the distal lesion, resulting in a flow reducing dissection, and therefore subsequently a stent implantation was performed. Since the transition between the stent and the muscle bridge showed a severe flexion with continued systolic compression of the vessel, two further stents were employed to reinforce the entire area of the muscle bridging. A fourth stent was implanted in the proximal lesion. In the following angiographic and IVUS examinations a systolic compression was not detectable and the CFVR increased to 3.3. In the 6 months follow-up coronary angiography a restenosis in the stented area by intimal hyperplasia could be observed. However, IVUS showed all stents to be circular and fully expanded without signs of compression by the muscle bridge.