Hyperthyroidism Associated Congestive Heart Failure: A Case-Control Study

Hyperthyroidism has been associated with cardiomyopathy and heart failure (hf). this study aims to evaluate clinical, laboratory and echocardiographic para-meters, at admission and 12 months fol-lowing euthyroidism restoration, in patients with hyperthyroidism-associated hf. mechanisms un-derlying hyperthyroidism-associated hf and the outcomes of echocardiographic parameters along the study period are both discussed. materials & methods: patients with newly di-agnosed overt hyperthyroidism and hf (group 1), age and sex-matched euthyroid hf subjects (group 2), and a control group were enrolled. results: in the 38-month study period, 56 pa-tients were admitted for hyperthyroidism-associated hf, of whom 71% had a pre-existing, mainly hypertensive, cardiomyopathy vs 68% of group 2 subjects. mean heart rate was signifi-cantly higher in group 1 than group 2 (127±38 vs 110±17bpm; p <0.02); 30 group 1 (54%) and 16 (29%) group 2 patients presented with atrial fi-brillation. at admission, left ventricular ejection fraction (lvef), end diastolic (lvedd) and end systolic (lvesd) diameters were lower, whilst lv mass (lvm), interventricular septum thick-ness (ivst) and lv posterior wall thickness (lvpwt) were increased in both groups com-pared to controls. at the end of the study, de-spite achievement of euthyroidism in all hyper-thyroid patients, mean lvef was not significant-ly different in group 2 but was significantly lower in group 1 patients compared to controls; lvm, ivst and lvpwt did not change in both study groups. conclusion: in our series, newly diagnosed hyperthyroidism-associated hf had 2.4% preva-lence. at the end of the study, lvef significant-ly improved in euthyroid, but not in hyperthy-roidism-associated hf patients compared to con-trols.