noun. The inability of a bodily organ or system, especially the circulatory system, to maintain adequate physiological function in the presence of disease.

noun. The inability to maintain defense mechanisms in response to stress, resulting in personality disturbance or psychological imbalance.

noun. Failing compensation of the heart in valvular disease.

noun. The inability of a diseased or weakened organic system or organ to compensate for its deficiency, resulting in functional deterioration.

noun. The deterioration of cognitive or emotional functionality in a person who is distressed or who suffers from a psychological disorder.

"Fetal echocardiography is essential for monitoring the pump twin for signs of decompensation and possible intervention."

decompensate  

Cath.  alkalosis  arrhythmia  broncho-pneumonia  cardialgia