| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
Ann Thorac Surg 1999;67:599-600
© 1999 The Society of Thoracic Surgeons
a Department of Thoracic Cardiovascular Surgery, Sapporo Medical University School of Medicine, South 1 West 16, Chuo-ku, Sapporo 060-8556 Japan
We thank Drs Choo and Duran for their comments. They have raised crucial points regarding our article [1]. The concept of root remodeling operations is to obtain appropriate coaptation of the aortic valve during diastole by tightening the dilated aortic root secondary to the aneurysm or dissection with a tube graft. In this operation, we aim not to copy the native aortic root, but to recreate the aortic root so that it produces maximal coaptation of the aortic valve [2]. We realize that the aortic root distends with pressure. Usually, the aortic valve remains competent, despite this distensibility. This phenomenon occurs at the expense of the width of the coaptation at the center [3]. The width decreases as the aortic root increases in diameter. The large redundancy of the coapting surfaces serves to keep the aortic valve from regurgitating. From this point of view, once, even in the flaccid heart, the diameter of the sinotubular junction is determined for the leaflets to meet at the center, the aortic valve will remain competent at various pressures. In addition, because the graft material is so stiff that the reconstructed aortic root does not expand despite high pressure, it is more likely that the leaflets will coapt centrally.
Another concern that Drs Choo and Duran address is that each intercommissural distance is not equal. However, we believe that the difference is so small that we can ignore it. For example, Sands and associates [4] reported that the percent of leaflet contribution to the total valve circumference was 34.3% in the noncoronary leaflet, 33.6% in the right coronary leaflet, and 32.2% in the left coronary leaflet. We have received similar criticisms, which have prompted us to conduct further studies. A comparison was performed between the predicted diameter obtained from our equation [1] and the measured one, using a molding technique [3]. A simple linear regression analysis showed a strong correlation between them. We plan to publish our results immediately after completion of this study.
Despite the considerable change in the sinotubular junction, the reason why we persist in determining its diameter is that the primary mechanism of this operation includes reducing the dilated sinotubular junction so that the aortic valve becomes competent. In patients with aortic valve regurgitation, information revealing appropriate graft sizing cannot be obtained easily from the beating heart. It is easier to predict the graft size with the aortic valve competent in the arrested heart. Yacoub and associates [2] also determine the size of the graft intraoperatively. We fully agree with Drs Choo and Duran that we still lack a precise knowledge of the aortic root. Further investigation of this issue is needed.
References
Related Article
This article has been cited by other articles:
|
|
 |
|
  R. A. Hopkins Aortic valve leaflet sparing and salvage surgery: evolution of techniques for aortic root reconstruction Eur. J. Cardiothorac. Surg., December 1, 2003; 24(6): 886 - 897. [Abstract] [Full Text] [PDF]
|
|
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| ANN THORAC SURG | ASIAN CARDIOVASC THORAC ANN | EUR J CARDIOTHORAC SURG |
| J THORAC CARDIOVASC SURG | ICVTS | ALL CTSNet JOURNALS |
