However, over-dosing or giving the drug for extended periods of time longer than one week has been shown to cause bradycardia (a slowing of the heartbeat) in some dogs, so it is not recommended for use
in dogs with heart problems.
Therefore, Merrick Classic does not provide the best «anti-inflammatory» food, nor the best choice
for dogs with heart problems, as it contains salt.
Those are often the toy breeds that have narrow or collapsed tracheas (windpipes)(ref),
dogs with heart problems or those debilitated by other chronic disease or old age.
For instance, the diabetic dog will require consistent energy and carbohydrate intake; dogs with kidney problems, a protein diet containing high quality protein; and
dogs with heart problems, a low salt diet.
Finally,
dogs with heart problems may have issues with the stresses associated with flying.
Dogs with heart problems should be get examined every 4 — 6 months for any heart related issues.
Similarly,
Dogs with a heart problem may cough after exercise or excitement, to reduce pressure of enlarged heart over lungs.