What are the causes of aortic insufficiency (AI)?

From the Guidelines

Causes of Aortic Insufficiency

Aortic insufficiency is primarily caused by conditions that lead to dilation or damage of the aortic valve or root, including endocarditis, rheumatic heart disease, and congenital abnormalities, such as bicuspid aortic valve 1.

• Common causes include:
  • Idiopathic dilatation of the aorta
  • Congenital abnormalities of the aortic valve, most notably bicuspid valves 1
  • Calcific degeneration
  • Rheumatic disease
  • Infective endocarditis
  • Systemic hypertension
  • Myxomatous degeneration
  • Dissection of the ascending aorta
  • Marfan syndrome 1
• Less common causes include:
  • Traumatic injuries to the aortic valve
  • Ankylosing spondylitis
  • Syphilitic aortitis
  • Rheumatoid arthritis
  • Osteogenesis imperfecta
  • Giant cell aortitis
  • Ehlers-Danlos syndrome
  • Reiter’s syndrome
  • Discrete subaortic stenosis
  • Ventricular septal defects with prolapse of an aortic cusp 1 These conditions can lead to aortic root dilation and subsequent valve incompetence, resulting in aortic insufficiency 1.

From the Research

Causes of Aortic Insufficiency

The causes of aortic insufficiency (AI) can be attributed to various factors, including:

• Intrinsic abnormalities of the aortic valve itself, such as leaflet destruction, prolapse, or restriction 2, 3
• Dilatation or geometric distortion of the aortic root 3, 4
• Aortitis, which can be caused by rheumatologic diseases such as ankylosing spondylitis, systemic lupus erythematosus, and Takayasu arteritis 2
• Syphilitic aortitis, which can lead to obliterative endarteritis and necrosis of the muscular and elastic fibers in the aortic media 5
• Diseases affecting the aortic valve, such as infective endocarditis, congenital bicuspid, and rheumatic valve disease 6
• Diseases affecting the walls of the aorta, such as syphilis and Marfan's dissection 6
• Diseases affecting both the aorta and the valve, such as ankylosing spondylitis 6

Underlying Mechanisms

The underlying mechanisms of AI can be complex and involve a combination of factors, including:

• Alteration of specific molecular pathways 3
• Genetic predisposition 3
• Changes in the mechanotransductive properties of the aortic valve apparatus 3
• Dilatation of the sinotubular junction, distortion or dilatation of the sinuses of Valsalva, and annuloaortic ectasia 4