Madias Christopher, Garlitski Ann C, Kalin John, Link Mark S
Cardiac Electrophysiology Service, Section of Cardiology, Rush University Medical Center, Chicago, IL, USA.
Cardiac Arrhythmia Center, Division of Cardiology, Tufts Medical Center (TMC), P.O. Box 197, 800 Washington Street, Boston, MA 02111, USA.
Cardiol Res Pract. 2016;2016:5191683. doi: 10.1155/2016/5191683. Epub 2016 Jan 26.
Background. In a commotio cordis swine model, ventricular fibrillation (VF) can be induced by a ball blow to the chest believed secondary to activation of mechanosensitive ion channels. The purpose of the current study is to evaluate whether stretch induced activation of the L-type calcium channel may cause intracellular calcium overload and underlie the VF in commotio cordis. Method and Results. Anesthetized juvenile swine received 6 chest wall strikes with a 17.9 m/s lacrosse ball timed to the vulnerable period for VF induction. Animals were randomized to IV verapamil (n = 6) or placebo (n = 6). There was no difference in the observed frequency of VF between verapamil (19/26: 73%) and placebo (20/36: 56%) treated animals (p = 0.16). There was also no significant difference in the combined endpoint of VF or nonsustained VF (21/26: 81% in verapamil versus 24/36: 67% in controls, p = 0.22). Conclusions. In this experimental model of commotio cordis, verapamil did not prevent VF induction. Thus, in commotio cordis it is unlikely that stretch activation of the L-type calcium channel with resultant intracellular calcium overload plays a prominent role.
背景。在心脏震荡猪模型中，胸部受到球击可诱发心室颤动（VF），据信这是机械敏感离子通道激活的继发结果。本研究的目的是评估牵张诱导的L型钙通道激活是否可能导致细胞内钙超载，并成为心脏震荡中VF的基础。方法与结果。对麻醉的幼年猪在VF诱发的易损期用速度为17.9米/秒的曲棍球对其胸壁进行6次打击。将动物随机分为静脉注射维拉帕米组（n = 6）和安慰剂组（n = 6）。维拉帕米治疗组（19/26：73%）和安慰剂治疗组（20/36：56%）动物观察到的VF频率无差异（p = 0.16）。VF或非持续性VF的联合终点也无显著差异（维拉帕米组为21/26：81%，对照组为24/36：67%，p = 0.22）。结论。在这个心脏震荡实验模型中，维拉帕米不能预防VF的诱发。因此，在心脏震荡中，L型钙通道的牵张激活以及由此导致的细胞内钙超载不太可能起主要作用。
