Predictors of Sudden Cardiac Arrest in Sarcoidosis

Quick Takes

  • In patients with the diagnosis of sarcoidosis, abnormal AV nodal function and bundle branch block substantially increase the risk of sudden cardiac arrest (SCA) in 8.6% of patients.
  • Other predictors of SCA include atrial fibrillation, heart failure, younger age, and African American identity.

Study Questions:

What are the electrocardiographic (ECG) and clinical predictors of sudden cardiac arrest (SCA) in sarcoidosis?


The authors examined the National Inpatient Sample (2005–2017) for sarcoidosis and SCA.


ECG markers of atrioventricular (AV) node dysfunction or bundle branch block were associated with substantially increased risk of SCA in a limited proportion of patients (8.6%). Second-degree AV block and third-degree AV block as well as right bundle branch block, left bundle branch block, and fascicular blocks were independently predictive of higher rates of SCA. This association was also observed among younger patients (<40 years) and those with normal ventricular function and African Americans. The presence of atrial fibrillation (AF) and heart failure was associated with higher odds of SCA.


The authors concluded that ECG evidence of AV nodal dysfunction or distal conduction disease should raise suspicion for cardiac involvement in patients with sarcoidosis and is associated with increased risk of SCA. The sensitivity of ECGs is, however, limited and presence of a normal ECG does not reflect a low risk of SCA.


SCA may be the initial presentation of cardiac involvement in patients with extracardiac sarcoidosis. The diagnosis of cardiac involvement usually requires advanced imaging such as positron emission tomography and cardiac magnetic resonance, but these are expensive and do not lend themselves for screening in the general population of patients with extracardiac sarcoidosis. The authors of this study identified AV nodal dysfunction and distal conduction disease as predictors of higher risk of SCA in those patients, with high specificity but poor sensitivity. It is notable that 68% of the SCA occurred in patients with normal left ventricular function, and that African American patients with cardiac sarcoidosis are at the greatest risk of SCA.

Clinical Topics: Arrhythmias and Clinical EP, Heart Failure and Cardiomyopathies, Noninvasive Imaging, Prevention, Implantable Devices, EP Basic Science, SCD/Ventricular Arrhythmias, Atrial Fibrillation/Supraventricular Arrhythmias, Acute Heart Failure, Computed Tomography, Magnetic Resonance Imaging, Nuclear Imaging

Keywords: African Americans, Arrhythmias, Cardiac, Atrial Fibrillation, Atrioventricular Block, Bundle-Branch Block, Death, Sudden, Cardiac, Electrocardiography, Heart Arrest, Heart Failure, Magnetic Resonance Imaging, Positron-Emission Tomography, Risk Factors, Sarcoidosis, Secondary Prevention

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