Sleep Apnea and Sudden Cardiac Death

Abstract

Sleep plays an integral role in maintaining health and quality of life. Obstructive sleep apnea (OSA) is a prevalent sleep disorder recognized as a risk factor for cardiovascular disease (CVD) and arrhythmias. Sudden cardiac death (SCD) is a common and devastating event. Out-of-hospital SCD accounts for the majority of deaths from cardiac disease, which is the leading cause of death globally. A limited but emerging body of research have further elaborated on the link between OSA and SCD. In this article, we aim to provide a critical review of the existing evidence by addressing the following: What epidemiologic evidence exists linking OSA to SCD? What evidence exists for a pathophysiologic connection between OSA and SCD? Are there electrocardiographic markers of SCD found in patients with OSA? Does heart failure represent a major effect modifier regarding the relationship between OSA and SCD? What is the impact of sleep apnea treatment on SCD and cardiovascular outcomes? Finally, we elaborate on ongoing research to enhance our understanding of the OSA-SCD association.

Keywords: Obstructive sleep apnea; QTc; Sleep; Sudden cardiac death; Ventricular arrhythmia.

Figure 1.

Shared risk factors between sudden cardiac death and obstructive sleep apnea. CAD, coronary artery disease; HRV, heart rate variability; HTN, hypertension.

Figure 2.

Proposed complex pathophysiology connecting obstructive sleep apnea (OSA) and sudden cardiac death (SCD). APD50, action potential duration 50%; I_Kr, rapid delayed rectifier current; I_Ks, slow delayed rectifier current; I_Kur, ultra rapid delayed rectifier current; I_Na-L, late sodium current; ITP, intrathoracic pressure; LTCC, L-type calcium channel; ROS, reactive oxygen species.