Characterization of atherosclerosis in a patient with familial high-density lipoprotein deficiency

Area of Science:

• Cardiovascular Medicine
• Lipid Metabolism
• Genetics

Background:

• Familial HDL deficiency, or Tangier disease, is characterized by extremely low levels of high-density lipoprotein (HDL) cholesterol.
• This condition is associated with massive foam cell accumulation in various tissues.
• The impact of severe HDL deficiency on atherosclerosis development remains incompletely understood.

Observation:

• A 60-year-old homozygous patient with Tangier disease presented with chest pain.
• Coronary angiography and intravascular ultrasound were performed to assess cardiovascular status.
• Left ventricular function was normal, with diffuse coronary sclerosis but no critical stenosis.

Findings:

• Intravascular ultrasound showed normal arterial wall structure without significant atherosclerotic plaques, intimal hyperplasia, or calcification.
• Only a single, discrete atherosclerotic lesion was noted in one iliac artery segment.
• Contrary to expectations, severe atherosclerosis was not observed despite the patient's known HDL deficiency and foam cell formation.

Implications:

• These findings suggest that severe HDL deficiency and foam cell formation in Tangier disease may not invariably lead to accelerated or severe atherosclerosis.
• Further research is needed to elucidate the complex interplay between HDL levels, lipid metabolism, and atherogenesis in rare genetic disorders.
• This case highlights the potential for cardiovascular health despite profound lipid abnormalities, prompting a re-evaluation of atherosclerosis risk factors.