TY - JOUR
T1 - Early peripheral responses to intravenous L-thyroxine in primary hypothyroidism
AU - Ladenson, Paul W.
AU - Goldenheim, Paul D.
AU - Cooper, David S.
AU - Miller, Matthew A.
AU - Ridgway, E. Chester
PY - 1982/10
Y1 - 1982/10
N2 - The metabolic, cardiovascular, renal, and pulmonary responses of 10 hypothyroid patients were studied during the first week of therapy with intravenous levothyroxine (L-thyroxine), 100 μg per day. Mean serum thyroxine, triiodothyronine, and reverse triiodothyronine concentrations were normalized within four days. Significant decreases in serum thyrotropin, creatine phosphokinase, and cholesterol levels, and an increase in the basal metabolic rate, were observed. An early cardiovascular response was demonstrated by serial measurement of the mean pre-ejection period (138 to 134 msec, p < 0.05), its ratio to left ventricular ejection time (0.49 to 0.46, p < 0.02), and pulse-wave arrival time (236 to 224 msec, p < 0.05). The mean renal excretion of a water toad (four hours) increased (54 to 77 percent, p < 0.02) by the fourth day. The blunted ventilatory responses to hypercapnea seen in two patients were improved. We conclude that a physiologic replacement dose of intravenous L-thyroxine for one week produces significant responses in organ systems responsible for the common clinical complications of myxedema.
AB - The metabolic, cardiovascular, renal, and pulmonary responses of 10 hypothyroid patients were studied during the first week of therapy with intravenous levothyroxine (L-thyroxine), 100 μg per day. Mean serum thyroxine, triiodothyronine, and reverse triiodothyronine concentrations were normalized within four days. Significant decreases in serum thyrotropin, creatine phosphokinase, and cholesterol levels, and an increase in the basal metabolic rate, were observed. An early cardiovascular response was demonstrated by serial measurement of the mean pre-ejection period (138 to 134 msec, p < 0.05), its ratio to left ventricular ejection time (0.49 to 0.46, p < 0.02), and pulse-wave arrival time (236 to 224 msec, p < 0.05). The mean renal excretion of a water toad (four hours) increased (54 to 77 percent, p < 0.02) by the fourth day. The blunted ventilatory responses to hypercapnea seen in two patients were improved. We conclude that a physiologic replacement dose of intravenous L-thyroxine for one week produces significant responses in organ systems responsible for the common clinical complications of myxedema.
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U2 - 10.1016/0002-9343(82)90323-0
DO - 10.1016/0002-9343(82)90323-0
M3 - Article
C2 - 7124775
AN - SCOPUS:0019918767
SN - 0002-9343
VL - 73
SP - 467
EP - 474
JO - The American journal of medicine
JF - The American journal of medicine
IS - 4
ER -