I knew I should have kept my dog on heartworm preventive all year-round, but I just let it slip my mind. Now that he has heartworms, does that mean the end?

No, heartworm disease is not a death sentence for your dog. Since at least 1970, there has been effective heartworm treatment to remove heartworms from dogs. Until 10 years ago, heartworm treatments had greater risk than they do now, and the likelihood of failure to remove all of the adult heartworms with one treatment was greater, but even then the diagnosis wasn’t a death sentence.

Still, a finding of a positive test for heartworms in your dog is cause for concern. Your dog must undergo a thorough evaluation. At a minimum, he must have a physical examination, which will evaluate all of the things your pet’s doctor can see, feel, hear and smell about your dog.

If there are areas of the physical examination that concern him, or other factors such as age or cough, blood and urine tests may be ordered. A chest X-ray may be needed, possibly with both top-to-bottom and side-to-side views of the heart and lungs. An electrocardiogram (EKG) may be required as well. Each patient will be evaluated individually.

The recommendation for most parts of the world is for dogs to be on heartworm preventive year-round. Taking your pet off preventive for the winter, only to have him tested and put back on in the spring, is neither safe nor cost-effective.

Jim Randolph is a veterinarian at Animal General Hospital in Long Beach, Miss.