Alterations in Left ventricular End-systolic Wall Stress During Short-term Follow-up After Correction of Isolated Congenital Aortic Stenosis

선천성 대동맥 협착증의 술전 및 술후 단기간의 수축말기 좌심실 내벽 스트레스의 변화

  • 김시호 (연세대학교 심장혈관센터 심장혈관외과)
  • Published : 2000.10.01

Abstract

Congenital aortic stenosis in children is characterized by "excessive" left ventricular hypertrophy with reduced left ventricular systolic wall stress that allows for supernormal ejection performance. We hypothesized that left ventricular wall stress was decreased immediately after surgical correction of pure congenital aortic stenosis. Also measuring postoperative left ventricular wall stress was a useful noninvasive measurement that allowed direct assessment for oxygen consumption of myocardium than measuring the peak systolic pressure gradient between ascending aorta and left ventricle for the assessment of surgical results. Material and Method: Between September 1993 and August 1999, 8 patients with isolated congenital aortic stenosis who underwent surgical correction at Yonsei cardiovascular center were evaluated. There were 6 male and 2 female patients ranging in age from 2 to 11 years(mean age, 10 years). Combined Hemodynamic-Ultrasonic method was used for studying left ventricular wall stress. We compared the wall stress peak systolic pressure gradient and ejection fraction preoperatively and postoperatively. Result: After surgical correction peak aortic gradient fell from 58.4${\pm}$17.6, to 23.7${\pm}$17.7 mmHg(p=0.018) and left ventricular ejection fraction decreased but it is not statistically significant. In the consideration of some factors that influence left ventricular end-systolic wall stress excluding one patient who underwent reoperation for restenosis of left ventricular outflow tract left ventricular end-systolic pressure and left ventricular end-systolic dimension were fell from 170.6${\pm}$24.3 to 143.7${\pm}$27.1 mmHg and from 1.78${\pm}$0.4 to 1.76${\pm}$0.4 cm respectively and left ventricular posterior wall thickness was increased from 1.10${\pm}$0.2, to 1.27${\pm}$0.3cm but it was not statistically singificant whereas left ventricular end-systolic wall stress fell from 79.2${\pm}$24.9 to 57.1${\pm}$27.6 kdynes/cm2(p=0.018) in 7 patients. For one patient who underwent reoperation peak aortic gradient fell from 83.0 to 59.7 mmHg whereas left ventricular end-systolic wall stress increased from 67.2 to 97.0 kdynes/cm2 The intervals did not change significnatly. Conclusion ; We believe that probably some factors that are related to left ventricular geometry influenced the decreased left ventricular wall stress immediately after surgical correction of isolated congenital aortic stenosis. Left ventricular wall stress is a noninvasive measurement and can allow for more direct assesment than measuring peak aortic gradient particularly in consideration of the stress and oxygen consumption of the myocardium therefore we can conclude it is a useful measurement for postoperative assessment of congenital aortic stenosis.

Keywords

References

  1. Am. J. Cardiol v.42 Congental heart diseasem a cohorl of 19,502 birth long-lerm follow up Hoffman JE, Christianson, R.
  2. Study of 51 patnents. Am. J. Cardiol v.38 Discrete subralvular aortic stenosts in cluldhood Newfeld EA, Muster AJ, Paul MH,(et al)
  3. Circulation v.60 Ventrcular performance pump fucntion and compensatory mechanisms in patients with aortic stenosis Spann JF, Bove AA, Natarjan, G, Kreulen T.
  4. Circulation v.75 Unexpected peristence into adulthood of low wall stress in patrents with congental aortic stenosts : Is there a fundamental difference in the hypertrophic response to a pressure ovelload present from birth Assey ME, Wisenbaugh T, Spann JF(et al)
  5. Am. J. Catdiol v.37 Combined hemodynanucultrasonic method for studying left ventrl cular wall stress Druce RB, Lambert PM, William, G
  6. Princlples and practocle of echocardiography. 2nd Ed Weyman AE.
  7. Circulation v.57 Interval as a predictor of sudden death in patents with myocardial infarction Schwartz PI, Wolf S. QT
  8. Circulation v.78 Alterations in left ventricular geometry wall stress and ejection preformance after correction of congenital aortic stenosts Dorn GW, Donnet R. Assey ME, Spann JF Jr,(et al)
  9. J. Clin Invest v.47 Control of myocardial oxygen consumption Graham TP Jr, Covell JW, Sonnenblick EH,(et al)
  10. Cardiac catheterization and Angiography. 3rd Ed. Grossman W.
  11. Am. J. Cardiol v.52 Fixed subaortic stenosis in the young : medical and surgical course in 83 patients Wright GB, Keane JF, Nadas AS,(et al)
  12. Br Heatt. J v.43 Fate of patients with flsed subaortic stenosis after surgical removal Somerville J, Stone S, Ross D
  13. Follow up of 17 years. Circulation v.66 Clintcal presentation and natural history of mild dicrete subaortic stenosis Shem-Tov A, Newfeld HN
  14. Circulation v.72 no.3 Altered left ventricular mechanics in pathents with ralvular aortic stenosis and coarcuon of the aorta effects on systohc performance and late outcome Botow K.M, Colan SD, Neumann A.
  15. Ped Cardiol v.14 Altered cardiac repolarization during exercise in congennal aortic stenosis Bastianon V, Del Bolgia F, Boscioni M(et al.)
  16. Pediatries v.53 Sudden death in young patients with congental aortic stenosis Kiely B.
  17. Am. J. Cardiol v.34 Sudden imexpected death from candrovascular disease in children Lambert, E, Menon VA, Wagner HR, Vlad P.
  18. Am. Heart. J v.54 Congenital deaf-mutism and functional heart disease with prolongation of the QT interval and sudden cardiac death Jervell A. Lange Nielsen F