Atrial fibrillation is frequently observed in patients who undergo M V R. It causes low cardiac output syndrome and is sometimes fatal.
The purpose of this study is a hemodynamic comparison of two kinds of prosthetic valves, the Hancock porcine xenograft and the Starr-Edwards 6520 discoid valve, by the observation of stroke volume measured by Minnesota impedance cardiography in the patients who had atrial fibrillation after MVR.
As a result, when a preceding R-R interval became less than 0.5sec, stroke volume was reduced to less than 10ml, in the patients who had tachy-arrhythmia after MVR, with the use of the Starr-Edwards 6520 discoid valve.
On the other hand, in patients in whom the Hancock porcine xenograft was used, the preceding R-R interval became less than 0.5sec and stroke volume was more than 10ml.
In conclusion the Hancock porcine xenograft is hemodynamically superior with the occurrence of tachy-arrhythmia compared with the Starr-Edwards 6520 discoid valve.
