Mesenteric Arteriopathies: Pathologies and Mimickers

Transcription

1 Mesenteric Arteriopathies: Pathologies and Mimickers Aditya Sharma Medical Director, Vascular Medicine Associate Professor of Median arcuate ligament syndrome Segmental arterial mediolysis Mesenteric vasculitis Spontaneous mesenteric dissections Mesenteric fibromuscular dysplasia Mesenteric Arteriopathies Median arcuate ligament syndrome / Celiac Artery Compression Syndrome / Dunbar syndrome Anatomical compression of the celiac axis and/or celiac ganglion by the MAL and diaphragmatic crura More in women (ratio of 4:1) Ages of 30 to 50 years & thin body habitus Symptoms: chronic postprandial abdominal pain (>80%), nausea, vomiting (55%), diarrhea, and unintentional weight loss (50%) Pathophysiology: Theories compressed celiac artery causes foregut ischemia resulting in epigastric pain (?collaterals) Pain is neuropathic from a combination of chronic compression & overstimulation of the celiac ganglion leading to direct irritation of sympathetic pain fibers and/or splanchnic vasoconstriction and ischemia. Radiographic studies: 10-24% have MAL physiology Symptomatic MALS: 2 /100,000 Radiographics Sep-Oct;25(5): JAMA Surg. 2016;151(5): AmSurg.2006;72(4): Korean J Radiol. 2001;2 (1):8-13. Median arcuate ligament syndrome: Diagnosis Expiration Inspiration Duplex abdominal ultrasonography during inspiration & deep expiration Compression noted in B-mode or color images Increased velocities in expiration and lowering of elevated velocities in inspiration Reliable indicator: Maximum expiratory peak velocity >350 cm/s & deflection-angles >50 Dynamic maneuvers are performed in CTA/ MRA/ conventional angiogram American Journal of Cardiovascular Disease Research. 2013, 1(1), 7-11 Eur J Vasc Endovasc Surg Feb;51(2): JAMA Surg. 2016;151(5): Ann Vasc Surg Jan;29(1):122.e1-7 Med Ultrason Mar;14(1):5-9.

2 Surgery. 1974;76(6): JAMA Surg. 2016;151(5): J Vasc Surg. 1985;2(1): Langenbecks Arch Surg. 2009;394(6): J Vasc Surg. 2007;46(4): J Vasc Interv Radiol. 1995;6(2): J Vasc Surg. 2015;62(1): J Vasc Surg.2009;50(1): Open Surgery: Decompression alone Decompression with celiac dilatation Decompression with reconstruction and bypass of the stenosed artery Patch angioplasty / reimplantation of celiac / bypass Ganglionectomy: pain resolution Laproscopic: small incisions & less postop morbidity Difficulty in controlling hemorrhage, potential for incomplete release, & higher risk of aortic injury Angioplasty alone has failed as 1 st line Rx Recurrent symptoms and stenosis: 1 st line Angioplasty +/- stenting Mesenteric bypass Symptom relief: Complete: 50% Partial: 73-82% Pancreaticoduodenal Artery Aneurysm Associated with Celiac Trunk Stenosis CT angiogram shows isolated pancreaticoduodenal artery aneurysm (white arrowhead) with peri-pancreatic hematoma between the hepatic artery (white arrow) and the superior mesenteric artery (black arrow). Pancreaticoduodenal arcades and the dorsal pancreatic artery form the main collateral pathways between the celiac axis and the SMA Not usually visible unless there is celiac or SMA stenosis Pathogenesis of PDA aneurysms: Increased flow in the small caliber vessels results in local arterial hypertension which then causes focal arterial wall weakening and true aneurysm formation Eur J Vasc Endovasc Surg Feb;51(2): Treatment: Ann Vasc Surg Jan;29(1):122.e1-7 Symptomatic i.e. bleeding aneurysm Coil embolization +/- MALS repair Asymptomatic aneurysm follow up imaging vs. Coil embolization with MALS repair vs. MALS repair Image courtesy: Bruce Gray, MD Mesenteric Fibromuscular Dysplasia Non-atherosclerotic / Non-inflammatory condition Commonly appears like a string of beads Visceral artery FMD: Prevalence US FMD registry: 19.3% (95/493) French ARCADIA registry: 17.5% (82/469) Polish ARCARDIA-POL registry: Mesenteric: 13.2% (19/144) Symptoms: Post-prandial, flank or abdominal pain, mesenteric ischemia, aneurysms, dissections or bruit HIGHER PREVALENCE OF ANEURYSMS & DISSECTIONS Visceral vs. non-visceral FMD: 41.2% or 35.6% vs. 19.7% vs. 20.6% (p<0.0001) US registry: 13.0% and 5.9% of all aneurysms and dissections respectively were visceral J Am Coll Cardiol Jul 12;68(2): Hypertension Sep;70(3):652-8 Journal of Hypertension. 2017;35:e151-e2 Circulation Jun 26;125(25): small aneurysms of middle colic artery Aneurysm of middle colic artery (arrowhead), string-of-beads appearance of SMA (small arrows), and small aneurysm of gastroduodenal artery Segmental Arterial Mediolysis Non-inflammatory Presentation: often emergent Hemorrhage, dissection, bowel infarction No sex predilection with mean age in late 50 s Mortality is VERY HIGH initially Radiographic appearance: arterial dilation, aneurysm/s (string of beads), dissecting hematoma, stenosis, occlusion Etiology: Unknown Correlation with abdominal surgery, Rx with adrenergic agonists, vasopressors and spinal anesthesia OFTEN CONSIDERED DIAGNOSIS OF EXCLUSION Arteries affected: Most common: celiac & branches (up to half cases) SMA & IMA & branches Renal & iliacs Cerebral and coronaries Some similarities to FMD, genetic disorders : Vascular Ehler s-danlos syndrome, vasculitis Histopathology: Vacuolar degeneration of the media Some preserved muscle cells (unlike cystic medial necrosis) RBC clusters and fibrin deposition in outer media AJR Am J Roentgenol Dec;187(6): Cardiovasc Pathol 2012;21:334 World Journal of Cardiovascular Disease 2013;3:64 J Vasc Interv Radiol 2011;22:1380

3 Congenital Vascular / Connective Tissue Disorders When to suspect? Presence of vascular abnormalities in other locations dissections, aneurysms, tortuosity Family history of aneurysms, sudden death, dissections Physical exam: Hyperflexibility, high-arched palate, high beighton score, bifid uvula, easy bruising, fragile skin, scoliosis, pectus abnormalities etc Lack of abnormal inflammatory markers Isolated Spontaneous Visceral Artery Dissection Often can be associated with connective tissue disorders such as Ehlers-Danlos syndrome, Loeys-Dietz syndrome, fibromuscular dysplasia Often have traditional cardiovascular risk factors: HTN, HLD & Smoking Conditions Ehlers-Danlos syndrome Loeys-Dietz syndrome Familial TAAD Marfan syndrome Mutations in Gene COL3A1 TGFBR1, TGFBR2, SMAD3, TGFB2, TGFB3 ACTA2, TGFBR2 FBN1 Types of dissection: Sakamoto classification Type I: Patent false lumen Type II: Cul-de-sac blind-ending false lumen without re-entry Type III: Thrombosed false lumen with ulcer-like projection Type IV: Thrombosed false lumen without ulcer-like projection Vascular Medicine 2017, Vol. 22(6) Eur J Radiol 2007; 64: Isolated Spontaneous Visceral Artery Dissection Long term complications: extension of the dissection aneurysmal degeneration chronic pain symptoms. Vasculitidies When to suspect? Constitutional symptoms: fever, chills, arthralgias, generalized symptoms Elevated inflammatory markers ESR/ CRP RF, ANA, ANCA etc Skin lesions: purpura, livedo reticularis Bowel thickening Vessel wall thickening: chronic long segment stenosis Microaneurysms / aneurysms in mesenterics and renals Purpuric erythema within the GI mucosa Vascular Medicine 2017, Vol. 22(6) J Vasc Surg 2011; 54:461-6 Tech Vasc Interv Radiol Dec;17(4): Best Practice & Research Clinical Gastroenterology 31 (2017) 85e96 RadioGraphics 2000; 20: Tech Vasc Interventional Rad 18:38-42

4 Vasculitis Imaging Other features Polyarteritis Nodosa Localized vasculitis of GI tract IgA vasculitis ANCA-associated vasculitis Takayasu arteritis Lupus vasculitis RA associated vasculitis Behcet s disease Hypocomplementemic urticarial vasculitis Microaneurysms w/ stenosis (renals, mesenteric & hepatic) Wall thickening w/ stenosis Bowel wall thickening & dilatation, intussusception, endoscopy- purpuric erythema of GI tract mucosa Bowel ulceration & ischemia Circumferential vessel wall thickening, stenosis, occlusion and aneurysms (chronic phase) Bowel and vessel wall thickening/edema, dilated bowels Bowel infarcts / edema / thickening Ileocecal ulcerations, VTE esp portal vein, pulmonary artery aneurysms Bowel edema Mononeuritis multiplex, skin lesions, orchitis, absent ANCA or glomerulonephritis Incidentally on surgical pathology Skin purpura, arthritis, hematuria, colicky abdominal pain + ANCA, glomerulonephritis, eosinophilia, Treatment: Immunosuppressive therapy Ischemia: Endovascular or surgical therapy Age<40, women, absent upper extremity pulses, bruits, Rash, arthritis, pleurisy, glomerulonephritis, low WBC/platelets + ANA, dsdna, anti-smith, low complements + RF / CCP, arthritis Oral / genital ulcers, skin lesions, pathergy test, PE, pulmonary artery aneurysms, ocular disease Angioedema, purpura, + anti-c1q antibody Mimics Best Practice & Research Clinical Gastroenterology 31 (2017) 85e96 Tech Vasc Interventional Rad 18:38-42 Standing/ Stationary Waves Benign radiological findings of unclear etiology Initially seen on angiograms but now even reported on CTA or MRA Etiology: Hypothesis Vasospasm Retrograde flow within the artery due to oscillations and physiological changes in the artery due to the contrast load injection Difference from FMD: Smooth and regular beads Case: 61-year old female patient with abdominal pain Vascular Medicine 2018, Vol. 23(2) Circulation: Cardiovascular Interventions. 2012;5:e9-e11 Courtesy Bruce Gray, MD

5 left colic artery biopsy: Fibromuscular dysplasia Multiple medial tears and dissections with aneurysmal formation without inflammation or atherosclerosis Secondary fibrointimal thickening with focal deficient internal elastic membrane in aneurysmal areas and poorly defined external elastic laminae The medial layer is mostly absent in areas of intimal proliferation, with focal preserved areas There is adventitial expansion An overlying organized thrombus is observed in one section, secondary to the medial tear and dissection observed Right Renal Artery Inferior Mesenteric Artery

6 Superior Mesenteric Artery Approach to Evaluation for Mesenteric Arteriopathies Circumferential wall thickening Vasculitis Connective tissue diseases : Other findings of CTD and aneurysms Trauma or procedural Intimal flap, Intramural hematoma Dissection Spontaneous No evidence of atherosclerosis or arterial thrombosis or embolism CT / MR findings Clinical hx: emergent presentation, constitutional symptoms, other symptoms- PT, migraines, hx of RA / SLE etc Physical exam: hyperflexibilty, skin lesions, livedo reticularis, arthritis Family hx: sudden deaths, aneurysms Imaging: aneurysms, dissections, MALS, wall thickening Labs: Inflammatory markers, rheum labs, genetic testing COL3A1, TGFBR2 etc Dynamic celiac compression +/- PDA aneurysms Beaded appearance Isolated multiple mesenteric aneurysms +/- GI bleed Median arcuate ligament syndrome Fibromuscular dysplasia: Likely FMD in other locations Regular beads: Standing waves Segmental arterial mediolysis FMD with mesenteric dissection