Chronic Venous Insufficiency and Duplex Ultrasound Examination

Jul 25, 2024

Chronic Venous Insufficiency and Duplex Ultrasound Examination

Introduction

  • Speaker: Philip Bendick, Technical Director, William Beaumont Hospital
  • Topic: Chronic Venous Insufficiency (CVI) and Lower Extremity Venous Duplex Ultrasound Examination

Overview of Venous Disease

  • Acute Venous Disease: Deep vein thrombosis (DVT), pulmonary embolism (PE)
  • Chronic Venous Disease: Predominantly CVI due to chronic changes post-thrombosis
  • Prevalence in the US:
    • Coronary atherosclerotic disease: ~3 million
    • Peripheral arterial disease: >5 million
    • Coronary artery disease: ~12 million (leading cause of death)
    • Chronic venous insufficiency: ~25 million (varicose veins and related conditions)
  • Economic Impact: Significant medical and economic problem

Pathophysiology

  • Elevated Venous Pressure: Chronic ambulatory venous hypertension
  • Standing vs. Supine:
    • Supine: Low venous pressure (5-10 mmHg)
    • Standing: Elevated venous pressure (up to 100 mmHg)
  • Chronic Changes: Dilation, leakage, tissue damage, and physical findings in lower extremities
  • Hemodynamics: Slow changes, respiratory cycle influence, and augmented flow with manual compression

CEAP Classification

  • Clinical signs: Grades 4-6, skin changes, and ulcerations
  • Etiology: Congenital, primary varicose veins, and secondary to other issues like DVT
  • Anatomy: Deep, superficial, and perforator systems
  • Pathophysiology: Obstruction, reflux, or both
  • Venous Clinical Severity Score: Tracks clinical progress and healing

Valvular Incompetence

  • Normal Valve Function: Prevents reflux, allows flow back to heart
  • Grading Incompetence:
    • Deep veins: Closure time <1 second normal
    • Calf veins, great/small saphenous veins: Closure time <0.5 seconds normal
    • Perforating veins: Closure time <0.33 seconds normal
  • Clinically Significant Reflux: Sustained reflux flow during and after augmentation

Three Venous Systems

  1. Deep Venous System:
    • Obstruction from thrombus, valvular incompetence
    • Examples of normal flow, obstruction, and recanalization
  2. Superficial Venous System:
    • Greater and Small Saphenous Veins (GSV and SSV)
    • New Terminology: GSV (medial thigh/calf), SSV (posterior calf)
    • Importance of fascial sheath in identifying true veins vs branches
  3. Perforator Venous System:
    • Connects deep and superficial systems
    • Important Perforators: Cockett, Boyd, Dodds
    • Function and incompetence leading to chronic venous changes

Hemodynamic Responses

  • Calf Muscle Pump: Enhances venous emptying, prevents ambulatory venous hypertension
  • Primary Varicose Veins: Failure to decrease pressure, leading to chronic issues
  • Augmentation Testing: Detection of reflux and valvular incompetence

Historical Context

  • Ancient Treatments: Vein stripping, ligation, and excision techniques
  • Modern Treatments: Ablation techniques (radiofrequency, laser), sclerotherapy

Post-Thrombotic Syndrome

  • Chronic Changes: Obstruction, valvular incompetence, combination
  • Venous Stasis Ulcers: Difficult to heal, often associated with incompetent perforators
  • Calf Muscle Pump Dysfunction: Leads to increased venous pressure

Treatment and Outcomes

  • Duplex Ultrasound: Key tool for documenting patterns of venous insufficiency
  • Saphenous Vein Treatment: Effective in preventing venous stasis ulcer recurrence
  • Incompetent Perforators: Importance in post-thrombotic patients

Conclusion

  • Duplex ultrasound is critical in documenting and managing chronic venous insufficiency patterns in superficial, deep, and perforator venous systems.