Zeitschrift für Kardiologie

, Volume 90, Supplement 6, pp 100–104

Turbulenz und High Intensity Transient Signals (HITS) als Parameter für die optimale Orientierung mechanischer Herzklappen

  • Mathias Perthel
  • J. Michael Hasenkam
  • Hans Nygaard
  • Wolfram Kupper
  • Joachim Laas
Article

Zusammenfassung

Hintergrund: Frühere Studien zeigten den Einfluss der Orientierung auf das hämodynamische Verhalten von mechanischen Aortenklappen. Diese Studie untersucht Turbulenz (RNS) und High intensity transient signals (HITS) als neue und objektive Parameter zur Beurteilung des hämodynamischen Verhaltens der mechanischen Aortenklappenprothesen, MH (Medtronic Hall) und SJM (St. Jude Medical). Methode: 4 Schweinen wurde ein Rotationsgerät implantiert, in welches sich sowohl SJM als auch MH-Klappen einsetzen ließen und welches die Drehung der Klappe ohne erneute Eröffnung der Aorta erlaubt. Anschließend wurden RNS und HITS in verschiedenen Orientierungen gemessen. Ergebnisse: RNS und HITS unterschieden sich in verschiedenen Orientierungen bei beiden Klappen. MH-Klappen zeigten die besseren Ergebnisse in ihrer hämodynamisch günstigsten Orientierung. RNS und HITS verhielten sich ähnlich, jedoch war keine 1:1-Korrelation nachzuweisen. Diskussion: RNS und HITS variieren in verschiedenen Klappendesigns und Orientierungen. Sowohl MH- als auch SJM-Klappen zeigten weniger RNS und weniger HITS in ihrer jeweils hämodynamisch günstigsten Position. Die besseren Ergebnisse ergaben sich für MH-Klappen. HITS stehen im Zusammenhang mit RNS und dem hämodynamischen Verhalten von mechanischen Aortenklappen.

Schlüsselwörter

Tubulenz High intensity transient signals (HITS) mechanische Aortenklappen 

Turbulence and high intensity transient signals (HITS) as a parameter for optimum orientation of mechanical heart valves

Summary

Background: In previous studies, the impact of valve orientation on the hemodynamic performance of mechanical aortic valves has been demonstrated. This study investigates Turbulence (RNS values) and High Intensity Transient Signals (HITS) as a new and objective parameter for hemodynamics in various orientations of Medtronic Hall (MH) and St. Jude Medical (SJM) aortic valves. Methods: Rotation devices carrying a MH or SJM valve were implanted into four pigs. The device allowed valve rotation without reopening the aorta. In various orientations, turbulent shear stresses (RNS values) and HITS were measured. Results: RNS and HITS changed for both valve designs in the different orientations, with superior results for the MH in the hemodynamically best orientation. Downstream turbulence (RNS) and HITS varied in the same direction, but a one to one correlation was not observed. Conclusions: RNS and HITS vary with respect to valve orientation and design with superior results for the tilting disc valve. Both MH and SJM valves showed lower turbulence and HITS counts in their hemodynamically best orientations. HITS were related to downstream turbulence and the hemodynamic performance of the mechanical aortic valves.

Key words

Turbulence high intensity transient signals (HITS) mechanical aortic valves 

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Copyright information

© Steinkopff Verlag 2001

Authors and Affiliations

  • Mathias Perthel
    • 1
  • J. Michael Hasenkam
    • 2
  • Hans Nygaard
    • 2
  • Wolfram Kupper
    • 3
  • Joachim Laas
    • 1
  1. 1.Herz-Kreislauf-Klinik Bevensen Herz- und ThoraxchirurgieBad BevensenGermany
  2. 2.Department of Cardiovascular ResearchUniversity Hospital Skejby SygehusAarhusDenmak
  3. 3.Herz-Kreislauf-Klinik Bevensen Kardiologie AkutBad BeversenGermany

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