Investigation of the Morphology of the Bicuspid Aortic Valve and Its Association with the Severity of Aortic Stenosis, Aortic Regurgitation, Ascending Aortic Dilation, and Associated Anomalies

Document Type : Original Article

Authors

1 Department of Cardiology, Imam Reza Hospital, Mashhad University of Medical Sciences, Mashhad, Iran.

2 Vascular and Endovascular Surgery Research Center, Mashhad university of Medical Sciences, Mashhad, Iran.

3 Medical Student, Mashhad University of Medical Sciences, Mashhad, Iran.

Abstract

Introduction: The bicuspid aortic valve (BAV) is the most common congenital cardiac anomaly. The abnormal bicuspid morphology of the aortic valve leads to valvular dysfunction and aortopathy. However, the clinical presentations of BAV are quite heterogeneous with variable valvular dysfunction and abnormalities. We aim to study the correlations between degrees of aortic stenosis and insufficiency, ascending aorta dilation and associated anomalies in different BAV phenotypes in our local population.
Method: In this cross-sectional study, patients who were referred for echocardiography for any reason and were diagnosed with BAV accidentally, as well as those who were candidates for cardiac surgery due to complications of BAV and referred for echocardiography before surgery, were included. The BAV phenotype was defined as anterior-posterior leaflet orientation (BAV-AP) or right-left leaflet orientation (BAV-RL). Aortic stenosis and insufficiency were assessed. Aortic dimensions were measured at the aortic annulus, sinuses of Valsalva, sinotubular junction (STJ) and ascending aorta. Other cardiac anomalies were also recorded.
Results: A total of 141 patients (mean age 34±12.8 ranging from 11 to 74 years) with BAV were enrolled. The male to female ratio was 3:1. The prevalence of BAV-AP and BAV-RL was 56.7% and 43.3%, respectively. Comparing BAV-AP and BAV-RL, no differences in age or in the prevalence of male sex were identified. The pattern of valvular dysfunction was not statistically different between the  two BAV phenotypes, with moderate-to-severe AI being the most common finding (60% in BAV-AP vs. 57.4% in BAV-AP; p= 0.982). Aortic diameter was larger with BAV-AP than BAV-RL at the sinuses (3.49±0.656 cm vs. 3.27±0.507 cm; p= 0.039). Additionally, ascending aorta dilation using the cut off according to sex, age, and body surface area was more common in patients with BAV-AP (60.8% vs. 43.1% in BAVRL; p= 0.043). The most common cardiac anomalies in all patients were patent foramen ovale (8.5%) and aortic coarctation(7.1%) .
Conclusion: This study shows that moderate-to-severe AI is the most common valvular dysfunction in BAV patients, which is one of the independent risk factors for cardiac events in these patients; however, the pattern of valvular dysfunction is not different according to BAV phenotype. BAV-AP is associated with larger sinuses of Valsalva and more prevalent ascending aorta dilation, suggesting the possibility of different hemodynamic derangements or etiological entities between the two types of BAV.

Keywords


  1. BACON AP, MATTHEWS MB. Congenital bicuspid aortic valves and the aetiology of isolated aortic valvular stenosis. QJM: An International Journal of Medicine. 1959 Oct 1;28(4):545-60.
  2.  Fenoglio Jr JJ, McAllister Jr HA, DeCastro CM, Davia JE, Cheitlin MD. Congenital bicuspid aortic valve after age 20. The American journal of cardiology. 1977 Feb 1;39(2):164-9.
  3. Yener N, Oktar GL, Erer D, Yardimci MM, Yener A. Bicuspid aortic valve. Annals of thoracic and cardiovascular surgery. 2002 Oct 1;8(5):264-7.
  4. Losenno KL, Goodman RL, Chu MW. Bicuspid aortic valve disease and ascending aortic aneurysms: gaps in knowledge. Cardiology Research and Practice. 2012;2012(1):145202.
  5. Lamas CC, Eykyn SJ. Bicuspid aortic valve—a silent danger: analysis of 50 cases of infective endocarditis. Clinical infectious diseases. 2000 Feb 1;30(2):336-41.
  6. Duran AC, Frescura C, Sans-Coma V, Angelini A, Basso C, Thiene G. Bicuspid aortic valves in hearts with other congenital heart disease. The Journal of heart valve disease. 1995 Nov 1;4(6):581-90.
  7. Kappetein AP, Gittenberger-de Groot AC, Zwinderman AH, Rohmer J, Poelmann RE, Huysmans HA. The neural crest as a possible pathogenetic factor in coarctation of the aorta and bicuspid aortic valve. The Journal of thoracic and cardiovascular surgery. 1991 Dec 1;102(6):830-6.
  8. Fernández B, Durán AC, Fernández-Gallego T, Fernández MC, Such M, Arqué JM, et al. Bicuspid aortic valves with different spatial orientations of the leaflets are distinct etiological entities. Journal of the American College of Cardiology. 2009 Dec 8;54(24):2312-8.
  9. Beppu S, Suzuki S, Matsuda H, Ohmori F, Nagata S, Miyatake K. Rapidity of progression of aortic stenosis in patients with congenital bicuspid aortic valves. The American journal of cardiology. 1993 Feb 1;71(4):322-7.
  10. Huang FQ, Le Tan J. Pattern of aortic dilatation in different bicuspid aortic valve phenotypes and its association with aortic valvular dysfunction and elasticity. Heart, Lung and Circulation. 2014 Jan 1;23(1):32-8.
  11. Dan L, Longo F, Harrison TR, Longo DL. Harrison's principles of internal medicine: McGraw-hill; 2011.
  12. Bonow RO, Mann DL, Zipes DP, Libby P. Braunwald's heart disease e-book: A textbook of cardiovascular medicine. Elsevier Health Sciences; 2011 Feb 25.
  13. Basso C, Boschello M, Perrone C, Mecenero A, Cera A, Bicego D, et al. An echocardiographic survey of primary school children for bicuspid aortic valve. The American journal of cardiology. 2004 Mar 1;93(5):661-3.
  14. Larson EW, Edwards WD. Risk factors for aortic dissection: a necropsy study of 161 cases. The American journal of cardiology. 1984 Mar 1;53(6):849-55.
  15. Osler W. The bicuspid condition of the aortic valves. Transactions of the Association of American Physicians. 1886;1:185-92.
  16. Siu SC, Silversides CK. Bicuspid aortic valve disease. Journal of the American College of Cardiology. 2010 Jun 22;55(25):2789-800.
  17. Michelena HI, Desjardins VA, Avierinos JF, Russo A, Nkomo VT, Sundt TM, et al. Natural history of asymptomatic patients with normally functioning or minimally dysfunctional bicuspid aortic valve in the community. Circulation. 2008 May 27;117(21):2776-84.
  18. Roberts WC, Ko JM. Frequency by decades of unicuspid, bicuspid, and tricuspid aortic valves in adults having isolated aortic valve replacement for aortic stenosis, with or without associated aortic regurgitation. Circulation. 2005 Feb 22;111(7):920-5.
  19. Tzemos N, Therrien J, Yip J, Thanassoulis G, Tremblay S, Jamorski MT, et al. Outcomes in adults with bicuspid aortic valves. Jama. 2008 Sep 17;300(11):1317-25.