Euthyroid Sick syndrome And Cardiac Failure In Zaria, Nigeria

The study was aimed at establishing the existence of sick euthyroid syndrome in our patients with cardiac failure and to find out whether the syndrome in the our patients has a peculiar pattern

Thirty subjects diagnosed with cardiac failure in NYHA class 3 and 4 were studied; they had clinical evaluation, electrocardiograph, chest radiograph and echocardiograph. The biochemical investigation included urea, electrolyte, and creatinine, thyroid function test (T3, T4 and TSH). Thirty individuals who served as control (age and sex matched) also had similar evaluation to the subjects.

The subjects' ages ranging from 17 to 85 years and a mean of 51.0 +/- 15.8 years compared to controls with a mean age of 48.9 +/- 8.1 years (p < 0.1). Twenty-two and eight patients were in NYHA class3 and 4 respectively. The subjects had a lower mean T3 than controls of 1.42 +/- 0.07 ug/l and 2.3 +/- 1.0 ug/l respectively and p < 0.001. The mean T4 levels were higher in the subjects than controls (85.4 +/- 26 ug/l and 70.0 +/- 1.7 ug/l respectively and p < 0.001) but TSH levels were similar in the two groups. The subjects had higher mean values of LAD, aortic root diameter, IVSD, LVIDD, LVPW, EDV ESV, LVM and LVMI (p < 0.05). The LV ejection fraction and fractional shortening were lower in subjects than controls (p <0.01). Six, seventeen and seven subjects had diastolic, systolic and combined diastolic-systolic dysfunction on echocardiography respectively. There was a positive correlation between T3 with duration of cardiac failure and ejection fraction (p < 0.05). There was a negative correlation between T3 and LVM, LVMI, LVIDD, EDV, LAD and cardio-thoracic ratio. The levels of T4 showed a positive relationship with LAD and CTR. Partial correlation was statistically significant between T3 and duration of cardiac failure, duration of aetiology of cardiac failure and LVM. The various forms of cardiac failure (diastolic, systolic and combined diastolic-systolic dysfunction) showed no statistically significant difference in mean levels of T3, T4 and TSH.

Euthyroid sick syndrome is also seen in Nigerians with cardiac failure as reported elsewhere and the levels of T3 seemed to be inversely proportional to LAD, CTR, LVIDD, LVM and LVMI. Serum T3 levels are also directly proportional to EF and FS. Low serum levels of T3 with normal T4 and TSH is associated with severe cardiac failure.