This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Endocrinology, Subject name: Medicine
Which of the following statements regarding treatment of hypothyroidism in a patient with Ischemic hea disease is true - 
Select and explain. 
A. Low dose of Levothyroxine, B. Normal dose of Levothyroxine, C. Do not use Levothyroxine, D. Use thyroid extract
A: Low dose of Levothyroxine
Answer: A: Low dose of Levothyroxine 
Explanation: In patients with known ischemic hea disease, thyroid hormone replacement using levothyroxine should be introduced at low dose and increased very slowly. The staing dose of levothyroxine is 12.5-25 mg/d with similar increments every 2-3 months until TSH is normalized. Exacerbation of myocardial ischemia, MI and sudden death are recognised complications of levothyroxine replacement, even using doses as low as 25 mg/day. Coronary angioplasty or bypass surgery may be required if angina is exacerbated by levothyroxine replacement therapy. Reference : page 2293 Harrison's Principles of Internal Medicine 19th edition and page 744 Davidson's Principles and practice of Medicine 22nd edition