Objective: To study the clinical significance of the function of heart and lung in patients with hypothyroidism with ple-thysmograph. Methods: The heart output and respiratory muscular force were measured by body plethysmography in 21 pa-tients before and after thyroidization. Results: The Qc, CI, SV, SI, FVC and FEV1 in the patients were significantly lower than those in control. Meanwhile, the decreased Qc, CI, SV, SI and FVC in the patients significantly restored along with the treatment of thyroidization. Conclusion: The heart output and respiratory muscular force were low in patients with hypothyroidism. But these changes could be conversed with thyroidization. The simple and non-invasive body plethys-mograph provides a new method to observe heart and lung function in patients with hypothyroidism.

To study the changes of pulmonary capillary blood flow and respiratory muscular force in patients with hyperthyroidism and the effect of antithyroidotherapy on them. Methods: The cardiac function and respiratory muscular force in 34 patients with hyperthyroidism were measured. Results:In patients,the levels of Qc and CI were higher and the levels of FVC,FEV1 and FIVC were lower than levels in the normal. Through antithyroidotherapy, these abnormal changes all re turned to normal. Conclusion:There are increased cardiac output and decreased respiratory muscular force in patients with hyperthyroidism, which are restorable during a therapeutic period.