Standing Arterial Waves Is NOT Fibromuscular Dysplasia

First International Consensus on the diagnosis and management of fibromuscular dysplasia

“…Entities that may be confused with multifocal FMD Systemic arterial mediolysis (SAM) 46 • Non-inflammatory, non-atherosclerotic disease • Manifests as spontaneous arterial dissection, rupture, occlusion, or aneurysm, most often in the abdominal visceral arteries • May be indistinct from multifocal FMD on angiographic imaging • Definitive diagnosis requires histopathological examination demonstrating vacuolar degeneration of the artery media Arterial spasm Standing waves 57,58 • Benign radiologic findings due to vasospasm such as those induced by ergotamine derivatives or sympathomimetic drugs or catheter-related vasospasm • Transient flow-related physiologic changes in the artery resulting in regular oscillations distinct from multifocal FMD (beading of varying size) • Neither entity requires further evaluation or follow-up when identified Imaging artifacts…”

Fibromuscular Dysplasia: State of the Science and Critical Unanswered Questions

“…There are times when this is mistaken for multifocal FMD (medial fibroplasia). 116 However, in standing waves, the undulations are in a regular pattern, without significant stenosis, and this rapidly reverses with infusion of a vasodilator or withdrawal of the catheter. 117 On the other hand, medial fibroplasia produces irregular areas of stenosis and dilatation.…”

Standing waves are not distinctive to conventional angiograms

“…Retrograde flow within the artery due to oscillations and physiological changes in the artery due to the contrast load injection are other potential theories. 1,2 Norton et al have reported standing waves on magnetic resonance imaging while Kroger et al have shown an angiographic correlation of the standing waves on ultrasonography. 3,4 These case reports, as well as our two cases, support the theory of standing waves being secondary to arterial flow-related physiologic changes and question the long-held belief that standing waves are specific to a conventional angiogram.…”