Chapter 103 - Atheromatous embolization and its management Flashcards
Synonyms of atheromatous embolization
1) cholesterol crystal emboli
2) Blue/purple toe syndrome
3) Atheroembolism
4) Pseudovasculitis
Treatment goals of atheromatous embolization
1) treat organ damage
2) prevent further embolization
3) risk factor modification for cardiovascular m&m
Incidence of atheromatous embolization
0.8-2.4%
Elder: 8.6-12.3%
Pt with cardiac/vascular procedure: 22-27%
Pt with AAA 77%
First description of atheromatous embolization
Panum in Germany centry ago
Flory 1945 characterized it accurately
Risks of atheromatous embolization: plaque characteristics
1) high plaque ulceration
2) thin fibrous cap with large lipid core
3) protruding mobile atheroma > 4 mm
4) lack of plaque calcification
Causes of atheromatous embolization
1) spontaneous
2) traumatic
3) iatrogenic
Histology of cholesterol crystal
1) white
2) rhomboidal/rectangular
3) elongate needle shape (if fixed in paraffin since it’ll dissolve)
4) 10 - 250 micron
5) double refractile crystal
6) Schultz stain: blue green
Pathogenesis of atheromatous embolization
1) inflammatory response with immediate infiltration of PMN and eosinophil
2) chronic inflammation 2-4 weeks
3) endothelial proliferation with fibrous tissue
4) luminal obliteration
Risk factors of atheromatous embolization: patient factors
1) aortic atherosclerosis
2) age > 60
3) CAD
4) PAD
5) AAA
Incidence of atheromatous embolization in cardiac surgery
0.2%
Incidence of atheromatous embolization in vascular surgery
2.9%
Use of anticoagulation in atheromatous embolization
controversial may increase embolization
Thrombolysis in atheromatous embolization
controversial
Cutaneous manifestation of atheromatous embolization
1) Livedo reticularis: net-like blue-red mottling
2) blue toe syndrome
3) petechiae
4) purpura
5) splinter hemorrhage
6) ulcers
7) raised nodules
Livedo reticularis differential
1) obstructive: antiphosphiolipid antibody, cryoglobulinemia, endocarditis, atrial myxoma
2) vasculitis
3) drug induced: quinidine, quinine, amantidine, catecholamine
4) physiologic: cutis marmorata
5) idiopathic: livedo vasculitis
Blue toe syndrome
cool painful cyanotic toes in presence of palpable distal pulses
Most common manifestation of atheromatous embolization
1) extremity
2) renal
3) GI
Pathogenesis of renal atheromatous embolization
1) mechanical obstruction
2) inflammatory reaction
3) glomerular sclerosis
4) tubular atrophy
5) intestinal fibrosis
Four different patterns of renal embolic disease
1) marked immediate impairment: massive embolization with catastrophic consequences
2) subacute disease (most frequent) with onset weeks after due to delayed inflammation
3) Insidious with stable subclinical chronic renal failure
4) HD-dependence with 21-39% resolve with partial recovery
Classic sign of atheromatous embolization renal failure
resistent hypertension
Mechanism of spontaneous renal recovery after atheromatous embolization HD dependence
1) reversal of inflammation
2) resolution of ATN
3) hypertrophy of surviving nephrons
Risk factors of poor renal recovery following atheromatous embolization
1) CHF
2) iatrogenic emboli
3) CKD
4) age > 70
5) acute/subacute onset
6) leg/GI involvement
7) DM
Protective factor for renal recovery following atheromatous embolization
Statins
Most common GI site for atheromatous embolization
1) colon 42%
2) SB 33%
3) stomach 12%
4) pancreas and liver –> rarely pancreatitis/hepatitis
5) gall bladder –> rare site but will cause chronic acaculous or acute gangrene cholecystitis
Most common GI symptoms following atheromatous embolization
1) GI bleed
2) abd pain
3) diarrhea
Diagnosis for GI embolism following atheromatous embolization
1) biopsy for cholesterol crystal
2) endoscopy - non-specific
Retinal involvement of atheromatous embolization manifest as this
Hollenhorst plaque
Hollenhorst plaque are
1) yellow
2) high refractile
3) retinal cholesterol emboli
4) low rate of concurrent ICA disease overall
Cerebral manifestation of atheromatous embolization
1) TIA/stroke
2) mental status change
3) headache
4) dizziness
5) organic brain syndrome
Laboratory investigations for atheromatous embolization
non-specific
only organ failure tests
atheromatous embolization vs ATN differences
1) ATN has pigmented cast and renal tubular cell, emboli is clear or microhematuria
2) ATN onset 48-72 hr while emboli has 7-10d delay
3) ATN likely full recovery while emboli rarely recover fully
4) ATN has normal BP while emboli has refractory HTN
Preventing atheromatous embolization
1) pre-op planning
2) proper endo technique
3) distal protection
4) glycoprotein IIb/IIIa inhibitor Abciximab
Treatment following atheromatous embolization: targeting source
1) steroids - poor evidence
2) statin for plaque stabilization
3) iloprost (prostacyclin analogue)
4) LDL apheresis
Surgical principles in treating atheromatous embolization source plaque
1) infrarenal aortic recon safer than suprarenal
2) endarterectomy or interpositional vs extraanatomical
3) endo may not be safe but covered stent better
Pain control following lower extremity atheromatous embolization
1) sympathectomy
2) spinal cord stimulation
1 year mortality following diseminated embolization
64-81%
