Sudden Cat Death: Tips for Understanding Why It Happens

One of the worst things a pet lover can experience is the sudden loss of their beloved cat. Trying to understand sudden cat death is excruciatingly painful. You want to make sense of what happened, consider what you could have done differently, and determine if there were health issues that you didn’t observe. It is most difficult to understand sudden cat death when it happens to a young animal. In this article, we discuss some of the possible causes of sudden cat death.

Feline Life Expectancy vs. Risk of Sudden Death

The life expectancy of cats can be anywhere from 14 to 22 years of age. There is a substantial difference in life expectancy depending on the individual cat lifestyle. Life expectancy can vary depending on if the cat is indoor only, indoor and outdoor, or outdoor only.

Indoor-only cats have the longest life expectancy, followed by cats that are both indoor and outdoor. Cats that live outdoors have the shortest lifespan, due to exposure to toxins, trauma, animal attacks, and infectious diseases. While this trend is a generalization, there are outdoor-only cats with good genes that are provided with a nutritious diet and veterinary care that have very long lifespans.

Possible Causes of Sudden Death in Cats

There are many causes of unexpected or sudden cat death.

As we consider illness and death in cats, one thing that is important to remember is that cats are very good at hiding their illness as a survival measure, which allows cats to be sick for a long time before anyone is aware. This can be especially true for those who spend everyday with their cat and don’t notice subtle changes like weight loss, shedding, sleeping more, or a dull hair coat. As our cats get older, we may believe that symptoms such as weight loss, less activity, and/or lethargy are from them slowing with age rather than from an illness.

Causes of sudden death in cats include:

• Trauma. This is more frequent in outdoor cats, but can occur to any animal. Examples of trauma include being hit by a vehicle, attacks or bites from dogs or other animals, gunshot wounds, falls, or random trauma, such as being crushed in a recliner. To learn more – read Trauma and Injuries in Cats. Outdoor cats are also at risk of getting lost and inadvertently putting themselves in harm’s way. Microchipping your pet can improve the chances of being reunited before an accident occurs. Click here to learn more.
• Toxins. Ingestion and/or exposure to toxins and medications is more common in outdoor cats, but can occur in indoor cats as well. Common toxins include antifreeze, potpourri, medications that contain acetaminophen, plant toxicity (such as from Easter lilies), and ingestion of rat poison. To learn more about toxic items, go to Toxins in Cats.
• Heart Disease. Heart disease may come with little to no warning sign. While some cats may have a history of a heart murmur, other cats can have no history of problems or abnormal symptoms. Some cats will demonstrate subtle symptoms such as playing less, sleeping more, decreased appetite, weight loss, or increased breathing rates. It is very common for cats to be of perfect health, only to show signs of illness rapidly and with grave circumstances. Cats with heart disease can develop difficulty breathing or have difficulty using their back legs, which may result in them crying out in pain. Some cat owners will simply find their cat dead without any indication of symptoms. The most common heart disease in cats is Hypertrophic Cardiomyopathy (HCM), a condition resulting in an abnormally thickened heart muscle. Feline heartworm disease can also cause sudden death.
• Heart Failure. When heart failure occurs, it means that the heart is no longer able to keep up with normal demands and functions of the body. This most commonly causes a fluid accumulation in the lungs known as pulmonary edema. The most common underlying cause for heart failure is Hypertrophic Cardiomyopathy. Signs of heart failure most often include a subtle decrease in appetite, less engagement in normal activities, and an increased respiratory rate. Some cats will be so short of breath that they will appear to pant with their mouths open, and cats will carefully mask their signs until they are in a state of fulminant and life-threatening heart failure.
• Heart Attack. A “heart attack” is the term commonly applied to people who have suffered a myocardial infarction (MI), often caused by coronary artery disease. The myocardium is the muscular tissue of the heart that receives nutrients and oxygen from the coronary arteries. Coronary arteries are small blood vessels in the heart muscle that bring blood from the aorta, which is the main artery of the body. When the muscle doesn’t receive normal blood supply, a heart attack occurs. Learn more about Heart Attacks in Cats.
• Blood Clot. A blood clot, also called a thromboembolism, may be caused by many different health issues, including heart disease in cats. Blood clots can go to the brain, lungs, or blood vessels in the back legs, resulting in sudden death in cats.
• Chronic Kidney Disease. Chronic renal failure (CRF) is a very common problem in cats. When the kidneys fail, they are no longer able to remove waste products that lead to the build-up of toxins in the blood. This produces clinical signs of kidney disease that include weight loss, decreased appetite, vomiting, and lethargy as the kidney disease progresses. Some cats with kidney disease will also have increased thirst and urination. This is most common in older cats, but can occur at any age. To learn more, read Chronic Kidney Disease in Cats.
• Feline Urinary Obstruction. Feline urinary obstruction (UO) is an acute obstruction of the urinary tract, and although this disease can affect any cat, it is most commonly found in males. This is also known as a “Blocked Cat.” Typical signs are straining to urinate and crying. When untreated, most cats will die within 72 hours. To learn more, go to Urinary Obstruction in Cats.
• Stroke in Cats. “Stroke” is a term commonly applied to people who have suffered a cerebrovascular accident (CVA) caused by cerebrovascular disease. A stroke is caused by the disruption of blood supply to the brain, which precipitates failure of nerve impulses to be transmitted from the brain to the rest of the body. The symptoms can come on quickly and cause sudden cat death. Signs of a stroke include difficulty walking, weakness, falling to one side, paralysis of one side of the body, and/or seizures. Click here to learn more about Strokes in Cats.
• Infections. Severe infections, commonly known as sepsis, can cause a progressive group of symptoms including lethargy, anorexia, weight loss, dehydration, fever, and sudden death in cats.
• Shock. Shock is defined as a profound life-threatening syndrome that results in low blood pressure and can lead to death. This can be caused by an allergic reaction, heart damage, severe infection (sepsis), trauma, blood loss, toxins, fluid loss, and spinal cord trauma. Cats with shock can die quickly, which may present as a sudden death.
• High Blood Sugar in Cats. Severe symptoms caused by uncontrolled diabetes can lead to weakness, lethargy, vomiting, coma, and death. Learn more about Diabetic Ketoacidosis (DKA) in Cats.
• Low Blood Sugar. Low blood sugar, also known as hypoglycemia, can cause lethargy, weakness, seizures, and sudden death. This can be an ill consequence of diabetes, from trauma, and/or various infectious diseases.

While it is extremely difficult to understand the loss of a beloved cat, especially at a young age, it does happen. There are reports of young athletes with no prior health problems suddenly dying while playing their sport, or a young “in shape” person in their 40s who goes out for a jog and drops dead. Sudden death can happen in cats as well, which can be just as devastating and make as little sense.

The only comfort you can take from this situation is knowing that you did the best you could and that you gave your cat a wonderful life. We at PetPlace hope this gives you some comfort.