Department of Medical Biology, Experimental and Clinical Pharmacology Research Group, UiT, The Arctic University of Norway, Tromsø, Norway.
Division of Diagnostic Services, Department of Clinical Pharmacology, University Hospital of North Norway, Tromsø, Norway.
Cardiovasc Res. 2019 Mar 1;115(3):501-509. doi: 10.1093/cvr/cvy305.
Moderate therapeutic hypothermia procedures are used in post-cardiac arrest care, while in surgical procedures, lower core temperatures are often utilized to provide cerebral protection. Involuntary reduction of core body temperature takes place in accidental hypothermia and ventricular arrhythmias are recognized as a principal cause for a high mortality rate in these patients. We assessed both clinical and experimental literature through a systematic literature search in the PubMed database, to review the effect of hypothermia on cardiac electrophysiology. From included studies, there is common experimental and clinical evidence that progressive cooling will induce changes in cardiac electrophysiology. The QT interval is prolonged and appears more sensitive to decreases in temperature than the QRS interval. Severe hypothermia is associated with more pronounced changes, some of which are proarrhythmic. This is supported clinically where severe accidental hypothermia is commonly associated with ventricular fibrillation or asystole. J-waves in human electrocardiogram recordings are regularly but not always observed in hypothermia. Its relation to ventricular repolarization and arrhythmias is not obvious. Little clinical data exist on efficacy of anti-arrhythmic drugs in hypothermia, while experimental data show the potential of some agents, such as the class III antiarrhythmic bretylium. It is apparent that QT-prolonging drugs should be avoided.
中度治疗性低温治疗用于心脏骤停后的护理，而在外科手术中，常采用较低的核心温度来提供脑保护。意外低温和室性心律失常会导致核心体温无意识下降，这些患者的高死亡率被认为是主要原因。我们通过在 PubMed 数据库中进行系统文献检索，评估了临床和实验文献，以综述低温对心脏电生理学的影响。从纳入的研究中，有共同的实验和临床证据表明，逐渐降温会引起心脏电生理学的变化。QT 间期延长，并且比 QRS 间期对温度降低更敏感。严重低温与更明显的变化相关，其中一些是致心律失常的。这在临床上得到了支持，严重的意外低温通常与心室颤动或心搏停止有关。在人类心电图记录中，J 波经常出现，但并不总是出现在低温中。它与心室复极和心律失常的关系并不明显。关于低温下抗心律失常药物的疗效的临床数据很少，而实验数据表明一些药物，如 III 类抗心律失常药物 Bretylium，具有潜在的作用。显然，应该避免使用延长 QT 间期的药物。
