Effect of Percutaneous Transluminal Angioplasty on Severely Stenotic Femoral Lesions
In Vivo Demonstration by Noninvasive Magnetic Resonance Imaging
The angiogram of a 68-year-old woman with severe claudication (Rutherford clinical class 3) of the right leg revealed a chronic high-grade preocclusive stenosis of the distal superficial femoral artery, with multiple collateral vessels (Figure 1A). Post-percutaneous transluminal angioplasty (PTA) angiography demonstrated restoration of both lumen and antegrade flow (Figure 1B). Cross-sectional magnetic resonance (MR) imaging performed 24 hours after PTA at the level of the arterial occlusion (Figure 2) revealed severe disruption and splitting of the atherosclerotic plaque, resulting in an irregularly shaped lumen. Angiographic and MR images were clearly discrepant, with angiography underestimating the residual lesion. The arrow in Figure 2F mimics the angio- graphic projection and explains why the angiography overestimated the result of the PTA.
This case provides in vivo evidence of extensive plaque disruption induced by balloon angioplasty, and may explain mechanisms of complications of this technique. Once such mechanisms such as thrombus formation are identified, targeted therapies can be more effectively chosen. In addition, it highlights the potential overestimation of PTA results by X-ray angiography as it underestimates the residual plaque size. Therefore, cross-sectional analysis by MR imaging could be useful in follow-up to define plaque remodeling and, perhaps, to identify prognostic factors for restenosis (eg, plaque splitting).
*Drs Corti and Wyttenbach contributed equally to this article.
The editor of Images in Cardiovascular Medicine is Hugh A. McAllister, Jr, MD, Chief, Department of Pathology, St Luke’s Episcopal Hospital and Texas Heart Institute, and Clinical Professor of Pathology, University of Texas Medical School and Baylor College of Medicine.
Circulation encourages readers to submit cardiovascular images to the Circulation Editorial Office, St Luke’s Episcopal Hospital/Texas Heart Institute, 6720 Bertner Ave, MC1-267, Houston, TX 77030.