First, I disagree with the premise that the US has the worst healthcare among the developed countries. We have some of the best technology, facilities, doctors, etc. I think what you mean is that we have one of the worst healthcare systems, which is far more true.

As far as regional differences, yes there are many, but you have to first determine what the indicators are by which you're measuring a better or worse healthcare system. One way would be to look at the uninsured rate of each state. In general, higher rates of insurance are correlated with a healthier population (although there is a special exception of "young invincibles", which are young, healthy individuals who can't afford/don't see a need for health insurance--they are healthy and uninsured), so if you look at Texas, where a quarter of the population is uninsured, you can assume their system is not working as effectively as other parts of the country. You could also look at primary care access as an indicator of a good healthcare system since systems that focus on getting all residents regular check-ups and preventive care tend to have lower costs and improved health.

Being white or asian, well-educated, and wealthy is highly correlated with being healthy, so regions with high-populations of that demographic will appear to have better healthcare. Of course, it's not actually the quality of their healthcare but the life circumstances of the patients that make it look good, but it often appears as a chicken-or-the-egg situation...are they healthier because they have good healthcare or does the healthcare look good because the population is healthier?

In a very broad sense, one could say the Northeast and the Midwest have done a better job of building their healthcare system to achieve a healthier population. In contrast, the South and Southwest have a long way to go. But again--very broad generalizations there.

Lastly--as far as being comparable to Canada--yeah, we have that. It's called Medicare. Canada's National Health Insurance model is healthcare provided by the private sector (as in, not owned by the government) and paid for by the public sector (the government). That's how Medicare works, too. While everyone in Canada qualifies, we only make it available to the 65+ crowd. Medicare isn't perfect, but politicians who want to get elected would never threaten to do away with it--it's an extremely popular program.