In both dogs and cats pulmonary oedema is a sign of left-sided congestive heart failure. In the cat pleural effusion may also be a side of left-sided congestive heart failure, whereas in the dog pleural effusion is always a sign of right-sided congestive heart failure. This species difference occurs because a proportion of the visceral pleural surface drains into the pulmonary veins, and this anatomic arrangement is more prominent in cats. | In both dogs and cats pulmonary oedema is a sign of left-sided congestive heart failure. In the cat pleural effusion may also be a side of left-sided congestive heart failure, whereas in the dog pleural effusion is always a sign of right-sided congestive heart failure. This species difference occurs because a proportion of the visceral pleural surface drains into the pulmonary veins, and this anatomic arrangement is more prominent in cats. |