What is the next step in managing a patient with a history of coronary artery bypass grafting (CABG) surgery, severe hyperpigmentation, and recurrent lower leg wounds/ulcers, with normal ankle-brachial indices (ABIs) and no evidence of small vessel disease?

Management of Recurrent Lower Leg Wounds with Normal ABIs Post-CABG

This patient requires referral to specialized wound care and evaluation for chronic venous insufficiency (CVI) as the primary cause of recurrent ulceration, given the severe hyperpigmentation and normal arterial perfusion studies. 1

Key Clinical Assessment

The normal ABIs (right 1.14, left 1.20) and normal toe-brachial indices definitively exclude peripheral arterial disease as the cause of these recurrent wounds. 1 The severe hyperpigmentation is a hallmark finding of chronic venous insufficiency, representing hemosiderin and melanin deposition from chronic venular hypertension and erythrodiapedesis. 2 This clinical picture—recurrent ulceration with hyperpigmentation in the setting of normal arterial perfusion—strongly indicates venous pathology rather than arterial insufficiency. 2

Immediate Next Steps

Specialized Wound Care Referral

• Patients with skin breakdown and recurrent ulceration should be referred immediately to healthcare providers with specialized expertise in wound care. 1
• The wound care specialist should devise a comprehensive plan to achieve complete wound healing, including appropriate debridement to convert chronic wounds into acute wounds that can progress through normal healing stages. 1, 3

Venous Insufficiency Evaluation

• Duplex ultrasound of the lower extremities is indicated to diagnose the anatomic location and severity of venous reflux. 1
• The evaluation should specifically assess for incompetent perforator veins, which are commonly associated with severe hyperpigmentation and trophic ulceration in the gaiter area. 4
• Assessment should include both superficial and deep venous systems to identify horizontal venous reflux patterns. 4

Treatment Algorithm

Primary Wound Management

• Aggressive debridement of nonviable tissue is the key initial step, as it converts chronic wounds into acute wounds capable of normal healing progression. 3
• Negative-pressure wound therapy (NPWT) dressings are helpful adjuncts when primary or delayed secondary closure is not immediately feasible. 1
• Specialized dressings and offloading strategies should be implemented based on wound characteristics. 1

Venous Insufficiency Treatment

• If significant venous reflux is identified on duplex ultrasound, surgical correction of horizontal venous reflux through subfascial perforator vein dissection should be considered, particularly given the severity of trophic changes. 4
• Compression therapy is the cornerstone of chronic venous insufficiency management, but must be carefully applied given the patient's post-CABG status and need to monitor for any arterial compromise. 5
• Inelastic compression (30-40 mm Hg) is more effective than elastic bandaging for managing venous edema while minimizing risk to arterial flow. 5

Cardiovascular Risk Factor Management

• Comprehensive cardiovascular risk factor modification must continue, including assessment of adherence to antiplatelet therapy, lipid management, and smoking cessation efforts. 1
• Given the four-vessel CABG history, this patient requires ongoing periodic clinical evaluation by a vascular specialist. 1

Common Pitfalls to Avoid

• Do not assume arterial insufficiency is the cause simply because of CABG history—the normal ABIs and TBIs exclude this diagnosis. 1
• Do not delay wound care referral—chronic wounds with severe hyperpigmentation require specialized expertise that goes beyond standard wound dressing changes. 1
• Do not initiate compression therapy without first confirming adequate arterial perfusion—although already confirmed in this case with normal ABIs, this is a critical safety check. 5
• Do not overlook venous pathology—severe hyperpigmentation with recurrent ulceration and normal arterial studies is pathognomonic for chronic venous insufficiency until proven otherwise. 2, 4

Follow-up Strategy

• Regular foot and leg examination with shoes and socks removed should occur at each follow-up visit after successful wound healing. 1
• Patients should receive verbal and written instructions regarding self-surveillance for wound recurrence. 1
• At least twice-yearly evaluation by a vascular specialist is warranted given the high recurrence rate of venous ulceration. 1
• Repeat duplex ultrasound should be performed if symptoms recur or new areas of hyperpigmentation develop. 1