Published online Mar 6, 2023. doi: 10.12998/wjcc.v11.i7.1549
Peer-review started: October 19, 2022
First decision: December 26, 2022
Revised: January 13, 2023
Accepted: February 15, 2023
Article in press: February 15, 2023
Published online: March 6, 2023
Processing time: 133 Days and 22 Hours
Hyperthyroidism often leads to tachycardia, but there are also sporadic reports of hyperthyroidism with severe bradycardia, such as sick sinus syndrome (SSS) and atrioventricular block. These disorders are a challenge for clinicians.
We describe three cases of hyperthyroidism with SSS and found 31 similar cases in a PubMed literature search. Through the analysis of these 34 cases, we found 21 cases of atrioventricular block and 13 cases of SSS, with 67.6% of the patients experiencing bradycardia symptoms. After drug treatment, temporary pacemaker implantation, or anti-hyperthyroidism treatment, the bradycardia of 27 patients (79.4%) was relieved, and the median recovery time was 5.5 (2-8) d. Only 7 cases (20.6%) needed permanent pacemaker implantation.
Patients with hyperthyroidism should be aware of the risk of severe bradycardia. In most cases, drug treatment or temporary pacemaker placement is recommended for initial treatment. If the bradycardia does not improve after 1 wk, a permanent pacemaker should be implanted.
Core Tip: Severe bradycardia, such as sick sinus syndrome and atrioventricular block, can occasionally be encountered in patients with hyperthyroidism. These pose a challenge for physicians. We report three cases of hyperthyroidism with severe bradycardia and identified an additional 31 cases indexed in PubMed. We found that hyperthyroidism with severe bradycardia may require 1 wk of observation before deciding whether to implant a permanent pacemaker. The use of drugs (e.g., atropine, isoproterenol, and/or anti-hyperthyroidism treatment), implantation of temporary pacemakers, and correcting the electrolyte disorder are recommended before permanent pacemaker implantation.