Echocardiographic left ventricular functional changes in acute hypothyroidism vs. subclinical hyperthyroidism in patients with differentiated thyroid carcinoma

In order to assess echocardiographic left ventricular functional indices in patients with differentiated thyroid carcinoma (DTC), after L-T4 withdrawal (short-term overt hypothyroidism) and during TSH suppressive therapy, we have evaluated cardiac hemodynamics in a single cohort study. 24 patients with DTC were studied in two phases: 1: at least 4 weeks after L-T4 withdrawal, 2: at least 8 weeks after beginning TSH suppressive therapy. All patients underwent conventional, Doppler and tissue Doppler echocardiography. Although early diastolic mitral inflow velocity (E wave) (p=0.033), and early diastolic velocity of mitral annulus [E(m)] (p Short-term overt hypothyroidism or L-T4 suppressive therapy in patients with DTC may have undesirable cardiovascular effects. So in patients with known history of cardiovascular abnormalities, the caring physician should be aware of the cardiovascular complications during hypothyroidism or suppressive therapy.