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Anterior pituitary hormone dysfunction among individuals with complete heart block requiring pacemaker
Bashir Ahmad Laway1, Arun Viswanath S1, Mohammad Salem Baba1
1Department of Endocrinology, Sher-I-Kashmir Institute of Medical Sciences, Srinagar, Jammu & Kashmir, India.
The Indian Journal of Medical Research
|October 9, 2024
Summary
Complete heart block (CHB) patients may develop hypopituitarism, characterized by anterior pituitary hormone loss. This study found significant hormone deficiencies in CHB individuals at 12-month follow-up, highlighting potential risks.
Area of Science:
- Endocrinology
- Cardiology
- Neurology
Background:
- Neuronal hypoxia, linked to traumatic brain injury and cardiac arrhythmias, is associated with hypopituitarism.
- Individuals with complete heart block (CHB) may be susceptible to long-term anterior pituitary hormone dysfunction.
Purpose of the Study:
- To investigate anterior pituitary hormone functions in individuals following CHB.
- To assess the prevalence of hypopituitarism in CHB patients.
Main Methods:
- A prospective cohort study of 30 CHB patients undergoing pacemaker implantation.
- Hormone levels (FSH, LH, TSH, TT4, FT4, cortisol, IGF-1, testosterone, estradiol) were measured.
- Fixed-dose glucagon stimulation test (GST) assessed growth hormone (GH) and adrenocorticotrophic hormone (ACTH) axes.
Main Results:
- At 12-month follow-up, 56.7% had low IGF-1, with 23% diagnosed with growth hormone deficiency (GHD).
- 20% exhibited ACTH deficiency, and one patient had TSH deficiency.
- Overall, 30% of participants showed anterior pituitary hormone deficiencies.
Conclusions:
- This pilot study indicates a significant incidence of anterior pituitary hormone loss in CHB individuals at 12 months.
- Undiagnosed hypopituitarism in CHB patients may contribute to morbidity and mortality.
- Further research is warranted to explore the long-term consequences and management strategies.
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