Preoperative Thyroid Assessment in Pacemaker Recipients: Are We Falling Short?

Area of Science:

• Cardiology
• Endocrinology
• Medical Databases

Background:

• Hypothyroidism is a reversible cause of bradyarrhythmias like atrioventricular blocks and sinus node dysfunction.
• Current guidelines recommend thyroid function assessment before pacemaker implantation.
• The study investigates the prevalence of preoperative thyroid dysfunction evaluation in pacemaker recipients.

Purpose of the Study:

• To assess the extent of preoperative thyroid function testing in patients undergoing pacemaker implantation.
• To identify the prevalence of different thyroid states (euthyroid, hypothyroid, hyperthyroid) in this population.
• To explore demographic and comorbidity factors associated with thyroid dysfunction in pacemaker recipients.

Main Methods:

• Analysis of a national database of transvenous pacemaker recipients from October 2004 to October 2024.
• Evaluation of preoperative thyroid-stimulating hormone (TSH) testing rates within 3, 6, and 12 months prior to implantation.
• Classification of patients based on thyroid profiles (euthyroid, subclinical hypothyroid, overt hypothyroid, subclinical hyperthyroid).

Main Results:

• Thyroid-stimulating hormone (TSH) testing was performed in 37.1% (3 months), 52.7% (6 months), and 70.2% (12 months) of recipients.
• Screening rates increased over time and with advancing age.
• Among 31,774 patients with available data, 15.7% had thyroid dysfunction (12.2% subclinical hypothyroid, 0.7% overt hypothyroid, 2.7% subclinical hyperthyroid).
• Patients with thyroid dysfunction were more likely to be female, older, and have more comorbidities.

Conclusions:

• Significant gaps persist in preoperative thyroid function evaluation for pacemaker recipients.
• A notable proportion of patients with thyroid dysfunction remain undiagnosed or undertreated before pacemaker implantation.
• Further investigation is crucial to clarify the relationship between thyroid status and the reversibility of cardiac conduction abnormalities.