Endocrine Abstracts

Changes in thyroid hormone function may have deleterious effects during cardiovascular surgery. Thus meticulous endocrinology consultation is demanded preoperatively. Thyroid dysfunction may present as subclinical or overt hypothyroidism, subclinical or overt hyperthyroidism, euthyroid sick syndrome, nodular goitre or minor elevations in thyroid hormone levels with normal TSH. The aim of the study was to determine retrospectively the prevelance of thyroid dysfunction in patients undergoing cardiac surgery.

Data from the endocrinology consultations for thyroid problems preoperatively for patients operated between the dates of 1’st of June 2008 to the 15’th of November 2008 at Kartal Kosuyolu Heart Education and Research Hospital were examined. Patients were operated for coronary bypass surgery, cardiac valvular surgery or peripheral bypass surgery. Total number of cardiovascular surgery was determined from the hospital database.

Of the 1615 patients operated 106 (6.5%) patients were consulted. Twenty patients (18.8%) had overt, 37 patients (34.8%) had subclinical hyperthyroidism, 22 patients (20.7%) had overt, 8 patients (7.6%) had subclinical hypothyroidism, 11 patients (10.5%) had minor elevations in free T4 levels, 3 patients (2.8%) had nodular goitre and were euthyroid and 5 patients (4.8%) had euthyroid sick syndrome. Among the patients with overt hyperthyroidism, 11 patients had diffuse uptake on thyroid scan, 6 had uptake suggestive of toxic nodules and 3 had no uptake. All patients had undergone angiography in a period of one week to 2 months prior to consultation.

In conclusion among thyroid disorders for which patients are consulted prior to cardiovascular surgery, subclinical followed by overt hyperthyroidism are more common than the other disorders. This may possibly be due to previous contrast patients are recieveing during angiography.