What are the clinical manifestations of Arteriovenous Malformations (AVMs) in the hand?

Clinical Manifestations of Hand AVMs

Hand arteriovenous malformations typically present as visible clusters of abnormal vessels without an associated solid mass, often accompanied by warmth, pulsatile swelling, and in advanced cases, signs of ischemia including pale/blue discoloration, pain, and potentially fingertip necrosis. 1

Visual and Physical Appearance

Fast-Flow Characteristics

• AVMs appear as a cluster of vessels without an associated solid tissue mass, distinguishing them from vascular tumors like hemangiomas 1
• The affected hand or digits may appear warm to touch with palpable pulses, even in cases with ischemic symptoms 1
• Visible dilated, tortuous vessels may be apparent on the skin surface, representing the abnormal arteriovenous connections 2, 3
• A pulsatile mass or swelling may be present in the affected area 2, 4

Progressive Ischemic Changes (Steal Phenomenon)

The hand can paradoxically show signs of inadequate blood flow despite increased vascular flow through the AVM, progressing through distinct stages 1:

Stage I: Pale/blue and/or cold hand without pain 1

Stage II: Pain during exercise or activity 1

Stage III: Pain at rest 1

Stage IV: Ulcers, necrosis, or gangrene of fingertips 1

Critical Warning Signs

Fingertip Necrosis

• Fingertip necroses are an alarming symptom that typically show initially slow progression over weeks, followed by rapid final deterioration leading to necrosis and gangrene 1
• This represents a surgical emergency requiring immediate vascular surgery referral, as delay can lead to catastrophic gangrene and hand amputation 1

Advanced Disease Presentation

• In severe cases, patients may present with digit necrosis, soft tissue infection, and osteomyelitis requiring amputation 5
• Hand-threatening ischemia secondary to steal phenomenon can occur when multiple AVMs divert blood flow away from distal structures 5

Diagnostic Imaging Appearance

Ultrasound with Doppler

• Fast-flow on Doppler ultrasound is the hallmark finding, showing arterialized flow in draining veins 1
• Multiple anechoic (dark) vascular spaces representing the abnormal vessel network 1
• Both arterial and venous waveforms are typically demonstrated 1

Angiography Findings

• Numerous AVMs with filiform (thread-like) flow through affected arteries 5
• Poor opacification of normal arterial structures in the hand due to steal phenomenon 5
• Direct arteriovenous shunting without normal intervening capillary bed 3, 4

Important Clinical Pitfalls

Differentiate from other conditions: Hand ischemia from AVMs must be distinguished from carpal tunnel compression syndrome, tissue acidosis, and edema from venous hypertension 1

Warm hand with ischemia: The presence of a warm hand with palpable pulses does NOT exclude severe ischemia—this paradoxical finding can occur with steal phenomenon and represents a critical diagnostic trap 1

Progressive nature: AVMs in the hand are evolutive lesions that can worsen over time, leading to serious complications including bleeding, skin ulceration, and in extreme cases, high-output cardiac failure 3