Complete Atrioventricular Block Complicating Hypothyrodism

Abstract

An 85-year old Thai woman was admitted to the hospital for dyspnea. Her ECG showed complete atrioventricular (AV) block. Her laboratory data upon admission revealed low serum thyroxine level and elevated thyrotropin level. Levothyroxine was started, and the AV conduction block was supported by a temporary pacemaker. At the end of the second week, her free T4 fell within normal range. The temporary pacemaker was subsequently removed. She was discharged without permanent pacing. This case demonstrated that hypothyroidism can cause complete atrioventricular block. Levothyroxine replacement can restore AV conduction in the hypothyroid patient.An 85-year old Thai woman was admitted to the hospital for dyspnea. Her ECG showed complete atrioventricular (AV) block. Her laboratory data upon admission revealed low serum thyroxine level and elevated thyrotropin level. Levothyroxine was started, and the AV conduction block was supported by a temporary pacemaker. At the end of the second week, her free T4 fell within normal range. The temporary pacemaker was subsequently removed. She was discharged without permanent pacing. This case demonstrated that hypothyroidism can cause complete atrioventricular block. Levothyroxine replacement can restore AV conduction in the hypothyroid patient.