There is no approved adulticide (medications to kill adult heartworms) treatments for cats. Adulticides are themselves dangerous. A single dead worm can be fatal in cats as it can break away and cause a blockage of the pulmonary artery (pulmonary embolism). Heartworms in cats have a shorter lifespan than those in dogs; therefore it is preferable to manage symptoms and use a wait and see approach.
Rapid breathing (tachypnea) is a respiratory disorder characterised by abnormal breathing that is rapid and shallow.  It is caused by a reduced level of oxygen, mechanical disorders (where the lungs aren’t able to expand as they should, usually due to a build-up of fluid in or around the lungs), and physiological disorders in which the cat’s respiratory centre in the brain is over stimulated.
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