The potential use of thiamine in patients with cardiac insufficiency.

Incremental doses of vitamin B1 were injected into patients with myocardial and pulmonary insufficiency treated in the post-operative period in the ICU (intensive care unit) after repairment of abdominal aneurysm. Compared to the control situation thiamine in a total dose of 50 mg/Kg induced a rise of blood pressure by at least 20 mmHg and a moderate elevation of central venous pressure by 3 mmHg. Heart rate was not affected and the EEG exhibited arousal effects after B1 treatment. It is suggested that in the failing heart with increased sympathetic tone thiamine acts as a mild peripheral vasodilator followed by a diminished pump outflow impedance and a resultant increase in systolic blood pressure. The redistribution of volume to the low pressure side is associated with a rise in central venous pressure. Effects of B1 on the EEG suggest an arousal reaction probably due to an interaction with a neurotransmitter system such as acethylcholine.