Τίτλος:
Effects of transient myocardial ischemia on the ventricular
defibrillation threshold
Γλώσσες Τεκμηρίου:
Αγγλικά
Περίληψη:
Background: Acute myocardial ischemia and the mode of ventricular
fibrillation (VF) induction influence the ventricular defibrillation
threshold (DFT).
Methods: Ventricular effective refractory period (ERP), ventricular
fibrillation threshold (VFT), and DFT were measured under nonischemic
conditions (control) in 26 pigs weighing 25-35 kg. Myocardial ischemia
was then induced by occlusion of the mid left anterior descending
coronary artery, and measurements of ERP and VFT were repeated after 2
minutes of Occlusion. The coronary artery ligation was released
immediately after the onset of VF and DFT was measured.
Results: LV ERP was unchanged by ischemia (199 +/- 19 ms at control vs.
200 22 Ins under ischemic conditions, P=0.799), whereas VFT was
significantly lower during coronary Occlusion (10.7 +/- 15.4 mA vs. 37.7
+/- 13 mA, P = 0.000). Brief myocardial ischemia caused a significant
increase in DFT (13.5 +/- 12.6 J after coronary occlusion vs. 6.8 +/-
6.8 J at control, P = 0.023). The duration of coronary occlusion was not
Correlated with the amounts of energy required to defibrillate (P =
0.526).
Conclusions: This experimental study shows that transient myocardial
ischemia markedly increases the DFT suggesting that specific
defibrillation algorithms should be designed for recipients of
implantable defibrillators at risk of myocardial ischemia.
Συγγραφείς:
Anastasiou-Nana, MI
Tsagalou, EP
Charitos, C
Siafakas, KX
and Drakos, S
Terrovitis, JV
Ntalianis, A
Doufas, A and
Mavrikakis, J
Nanas, JN
Περιοδικό:
PACE - Pacing and Clinical Electrophysiology
Λέξεις-κλειδιά:
defibrillation; ventricular fibrillation; ventricular ischemia
DOI:
10.1111/j.1540-8159.2005.09303.x
