erm . . . While I do feed my dog high quality food and bottled spring water* and use leftover meat and veggies for treats, I do not vaccinate yearly, nor do I use heartworm meds year round.
First of all, it's unnecessary to vaxx yearly. Most of the vaxxes last a lifetime. For example, what's the difference between a 1 year rabies vaxx and a 3 year rabies vaxx? Chemically, nothing. The manufacturer decided to test the 1 year vaxx for 3 years, it worked, so they sell a 3 year variety. The truth is, most vaxxes last at least 10-15 years, i.e., the lifetime of the average American dog.
Secondly, in a climate like Chicago and Northeastern PA, it is completely unnecessary to treat for heartworms year round. Heartworms are only a problem when misquitoes are present. Misquitoes aren't present in PA from October to May. Even when misquitoes are present, the heartworms won't grow unless you get 2 solid weeks when the temperature gets above 80F every day and never falls below 57F. In PA, that's usually June through September.
There are heartworm maps where you can find reported incidences of heartworm in your area. In mine, there are, on average, 5 reported cases a year. Mind you, that's just where the vet was who reported it, not where the dog was infected. A good many people in the Northeast own rescues transported from shelters in the South. All 5 of those dogs could have been infected in the South, then transported up north and diagnosed.
Anyway, this is all with the blessing of my vet, and from the experiences of my mother and grandfather, who did the same and never had a dog with rabies or heartworm.
*I'm not totally crazy. Even I can smell the chlorine in the tap water, I wouldn't expect a dog to drink it.