Medical Archive

Peripheral artery disease

Etiology

• Thrombosis in situ (~40%)
• Cardiac origin (~38%)
• Graft/angioplasty occlusion (~15%)
• Trauma

Diagnosis

• Intermittent claudication
  • Acute-on-chronic limb ischemia often lack classic features or develop them more slowly (eg, over 1 day) b/c of preexisting collateral circulation.
• Diminished pulses in ABI
  • Abnormal ABI (<1) – can be pulseless.
  • Severe ABI (<0.4)
• Thin, shiny, hairless skin

Treatment

• Graded daily exercise program
  • First-line.
  • Does not decreases future morbidity and mortality
• Antiplatelet
  • Aspirin, clopidogrel, ticagrelor
  • Reduces the risk of ischemic stroke, MI, and vascular death in patients with symptomatic PAD. But no symptomatic improvement.
• Anticoagulation
  • IV heparin
• ?????
  • Cilostazol (class I)
    • PDEi – inhibits platelet aggregation and acts as a direct arterial vasodilator.
    • P4 S3 C114 Antiplatelet, Anticoagulant, and Fibrinolytic Drugs
  • Pentoxifylline (class IIb)
  • Does not decreases future morbidity and mortality
• Prostacyclin (class III)
  • Prostaglandin E1: IV – alprostadil
  • Prostaglandin I2 (prostacyclin): po – Beraprost
• Thrombectomy
• Revascularization
  • With severe ABI (<0.4)
  • Angioplasty
  • Arteriography

Prognosis

Claudication

• 10%-20% of patients progress to worsening claudication
• 1%-2% progress to develop critical limb ischemia with rest pain, nonhealing ulcer, and tissue gangrene that may require limb amputation.

Cardiovascular morbidity and mortality

• Patients with PAD and intermittent claudication
  • 20% 5-year risk of nonfatal MI and stroke
  • 15-30% 5-year risk of death d/t cardiovascular causes
• Critical limb ischemia
  • 25% 1-year risk of cardiovascular mortality

Fibromuscular dysplasia

Pathophysiology

• Loss of internal elastic lamina. which can lead to the formation of aneurysms due to weakening of the wall.
• Alternating fibromuscular webs and aneurysmal dilation.
• FMD can involve any artery but most commonly the renal, cerebral(e.g., carotid, vertebral), and visceral arteries.

Clinical presentation

• 90% women (in adults)
• Internal carotid artery stenosis
  • Recurrent headache
  • Pulsatile tinnitus
  • Transient ischemic attack
  • Stroke
• Renal artery stenosis
  • Secondary hypertension
  • Flank pain

Physical exam

• Subauricular systoli bruit
  • In contrast with the carotid bulb, is not commonly affected by atherosclerosis.
• Abdominal bruit

Diagnosis

• Imaging preferred (eg, duplex US, CTA, MRA)
• Catheter-based arteriography

Treatment

• Antihypertensives (ACEi or ARBs 1st line)
• Percutaneous transluminal angioplasty or surgery
• Surgery (if PTA unsuccessful)

Thromboangiitis obliterans

= Buerger disease

Etiology

Segmental small & medium-sized vessel vasculitis
Likely triggered by tobacco smoke

Histopathology

Segmental, inflammatory vasculitis that affects the small- and medium-sized arteries and veins
Inflammatory intraluminal thrombi with vessel wall sparing
Extension into contiguous veins & nerves
Necrotizing vasculitis involving digits

Clinical features

• Age <45, predominantly men
• Symptoms typically begin distally (eg, digital ischemia) before progressing proximally.
• Presents with ulceration, gangrene, and autoamputation of fingers and toes; Raynaud phenomenon is often present.
• Often have normal distal pulses.

Treatment

• General measures
  • Complete cessation of smoking and the use of tobacco products is the single most important therapeutic measure 
  • Protection of fingers and toes from cold to prevent Raynaud phenomenon
• Medical therapy 
  • Prostaglandin analogue (iloprost)
  • Calcium channel blockers (nifedipine, amlodipine)
  • Hyperbaric oxygen therapy 
• Surgical therapy
  • Revascularization procedures (e.g., bypass grafting, angioplasty) usually cannot be performed because, typically, distal small and medium-sized arteries are involved. 
  • Patients with ulcers may require debridement and treatment with antibiotics.
  • Patients who develop gangrene in the extremities will require amputation.

Vasculitis

Acute limb ischemia

Atheroembolism

Thoracic outlet compression syndrome

Popliteal artery entrapment

Popliteal artery embolism

Arteriovenous fistula

• Femoral vein
  • Continuous bruit with a palpable thrill
  • Distal pulses may be diminished in the affected extremity
  • Untreated AVF can progressively enlarge and lead to limb edema, limb ischemia, and high-output heart failure.

Management

• Small AVFs: observation (sometimes resulting in spontaneous closure) or ultrasound-guided compression)
• Large AVFs: typically require surgical repair.

Raynaud’s phenomenon

	Primary	Secondary
Etiology	–	Connective tissue disease Occlusive vascular conditions Sympthomimetic drugs Vibrating tools Hyperviscosity syndromes Nicotine
Clinical presentation	Usually women age <30 No tissue injury Negative ANA & ESR	Usually men age >40 Symptoms of underlying disease Tissue injury or digital ulcers Abnormal anil fold capillary examination
Management	Avoid aggravating factors CCB for persistent symptoms	Evaluate & treat underlying disorder CCB for persistent symptoms, aspirin for patients at risk for digital ulceration.

Workup

• CBC and metabolic panel
• Urinalysis
• ANA and RF
  • If ANA is positive, specific antibodies (eg, antitopoisomerase-1 for systemic sclerosis) may be obtained)
• ESR and complement levels (C3 and C4)

Acrocyanosis

Livedo reticularis

Pernio(chilblains)

Erythromelalgia

Frostbite