Asked by user in Michigan.
My husband was on the job and had a heart attack. His employer put him in his care and left him there. He called me four hours later and I had to initiate the 911 call.
Generally speaking, there is no duty to render aid. However, the Michigan Supreme Court recognized a duty to render aid when there is a special relationship between the parties. One such special relationship is the "employer-employee" relationship. When a special relationship exists, the parties are required to render "reasonable care under the circumstances."
In other words, your husband's employer had a legal duty to render "reasonable care" to your husband. If your husband's employer failed to call 9-1-1 after learning that your husband had a heart attack, then they likely breached their legal duty to render reasonable care and could be held liable for any resulting harm.
I would recommend scheduling an initial consultation with a Michigan personal injury attorney to discuss your legal options.