“Increased Myocardial Wall Thickness in a Patient with Severe Hypothyroidism, Showed Complete Reversibility After Thyroid Hormone Replacement Therapy” Case Report and Literature Review

Abstract

Introduction: Hypothyroidism affects the cardiovascular system in various ways. This may include bradycardia, diastolic hypertension, increased systemic vascular resistance (SVR), decreased cardiac contractility, and cardiac output. Increased myocardial thickness is seldomly reported. The thickness can be secondary to edema, hypertrophy, substance deposition, or the combination of all three. Case summary: In this case report and review we present a patient with severe hypothyroidism and massive recurrent pericardial effusion, leading to cardiac tamponade that needed drainage twice at one-month intervals. Increased myocardial wall thickness of both the septum and the posterior walls was detected. The increased thickness completely recovered in six months duration after thyroid hormone replacement and restoration of euthyroid status. We ran a review on the effects of hypothyroidism on the heart and vascular system, with a focus on the incidence, possible etiology, and reversibility of increased tissue thickness in different body organs in hypothyroid patients. These organs are the skin, the myocardium, and the carotid intima. Conclusion: Severe hypothyroidism can cause increased myocardial thickness that is reversible after thyroid hormone replacement therapy. Increased thickness is also seen in the skin and the carotid intima. The pathophysiology is probable of various etiology, however myocardial edema seems to be a strong reason considering the quick recovery after treatment.