Arterial thrombosis at Unusual sites (EJH 2018)
Intro
Arterial thrombosis usually occurs as a result of atherosclerosis
Non-atherosclerotic causes for arterial thrombosis vary depending on the thrombotic site
A small minority of arterial thromboses remain unexplained - cryptogenic - after common causes have been excluded
No guidelines (that I am aware of, 2023) available for the haematological Ix/Mx of cryptogenic events.
Stats below are taken from review article linked in the title above, much of it based on very limited data
work-up for cryptogenic arterial infarct
After assessing for atherosclerosis, peripheral vascular disease, cancer screening, smoking/drug use, consider:
Cardioembolic causes: ECG, Telemetry, Doppler Echo
Acquired thrombophilia: FBC, PT/APTT, Antiphospholipid antibodies, JAK2 +/- BCR-ABL, HIT Screen, PNH Screen
intracardiac thrombi
Incidence: 2.7% post STEMI, 9% post anterior STEMI
Common causes: Anteroapical MI (LV thrombus), AF (atrial thrombus)
Hypercoagulable causes: Hypereosinophilic syndrome (HES)
Acute Mx: Triple therapy - DAPT + Oral anticoagulation for 3 months. Steroids + anticoagulation if HES
Notes: DOAC acceptable alternative to warfarin
primary aortic mural thrombus
Thrombus that appears almost free floating with potential to embolise. Most cases asymptomatic until embolism.
Incidence: 9% of pulmonary embolism
Common causes: Atherosclerosis, Aortic aneurysm, Primary aortic mural thrombus (absence of atherosclerosis)
Investigations: Echo, CT angiogram
Acute Mx: Anticoagulation, Aortic stenting, Surgical thrombectomy
Recurrence: High recurrence rate when treated with anticoagulation alone
renal infarction
Presentation: Abdo pain, flank pain, vomiting, fever
Incidence: 0.003% of hospital admissions
Common causes: Cardioembolic, Renal artery injury (e.g Traumatic, connective tissue disorders), Cryptogenic
Hypercoagulable causes: Nephrotic syndrome, Antiphospholipid syndrome
Investigations: Metabolic bloods, CT, Telemetry, Echo, Antiphospholipid antibodies, Vasculitis screen
Acute Mx: Interventional radiology
acute mesenteric (SMA) infarction
Incidence: 0.1% of hospital admissions
Common causes: Cardioembolic, Thrombosis, Dissection, Cryptogenic
Hypercoagulable causes: Nephrotic syndrome, Antiphospholipid syndrome
Investigations: ECG, Telemetry, Echo, FBC, Lactate, Antiphospholipid antibodies
Acute Mx: IV Heparin infusion, IV Abx, IV Fluids, Vascular surgery
Chronic Mx: CVS risk management, 1-3 months DAPT if endovascular repair, indefinite anticoagulation if cryptogenic/thrombophilia
adrenal infarction
Incidence: 3% of adrenal tumours
Common causes: Adrenal tumours, Meningococcal sepsis, IBD, Cardioembolic
Hypercoagulable causes: HIT, MDS, Antiphospholipid syndrome
Investigations: Metabolic bloods, PT/APTT, Echo, Telemetry, CT, HIT screen, JAK2, Antiphospholipid antibodies
Acute Mx: Treat underlying cause, anticoagulation if no associated haemorrhage
splenic infarction
Incidence: 0.016% of hospital admissions
Common causes: Cardioembolic, Haematological diseases associated with splenomegaly, Infection, Endocarditis, Malignancy, Cryptogenic
Hypercoagulable causes: Any hypercoagulable state
Investigations: FBC, CT, ECG, Echo, JAK2, Antiphospholipid antibodies, EBV serology, Haemoglobin electrophoresis
Acute Mx: Conservative with management of underlying cause. Anticoagulation. Surgery if complications present.
Chronic Mx: Indefinite anticoagulation for cryptogenic cases
cryptogenic acute limb ischaemia
Incidence: <0.1% of hospital admissions
Common causes: Peripheral vascular disease, Embolus from proximal thrombus, Trauma, Idiopathic
Hypercoagulable causes: Vasculitis, Antiphospholipid Syndrome
Investigations: CT/MR angiography, Telemetry, Echo, Vasculitis screen, Antiphospholipid antibodies
Acute Mx: IV Heparin infusion + Vascular surgery
Chronic Mx: Indefinite anticoagulation, warfarin or DOAC
Recurrence: 25% in cryptogenic cases