I hope this message finds you well, present circumstances excluded. I am a licensed attorney with over a decade of practice experience handling matters like this one. It is a pleasure to assist you today, though I wish the circumstances were different.
Quite honestly, it is hard for me to tell you that you have a sure fire law suit as a result of this issue without knowing the entire medical history, etc. That said, any lawyer that unequivocally tells you that you do or don't have a case without first looking at the medicals (and having an expert review the files), is lying to you. Just a word of advice.
That said, in order to have a viable medical malpractice claim, you must be able to show that the health care provider (HCP) breached the applicable standard of care for your geographic locale. The standard of care is the care that should be administered in your area by a reasonable and competent physician or HCP under the circumstances. The issue with the heart and proceeding forward makes me wonder if the standard of care was breached.
In order to win the case, you must show that the HCP had a duty, breached that duty, that the breach resulted in injury and you must prove damages. The duty and the breach of the duty are typically proven by the use of medical experts.
Based on what you have shared with me, in particular about the aggressive nature of the treatment and the results thereof, it sounds like you guys have a viable law suit here. However, there are variables in cases like this one - especially with individuals that have prior health issues.
You should most certainly visit with two or more different malpractice firms to discuss the case. You can use the above referenced information to keep them in check because you know the standards to bring and win the case.
Let me know if you have any other questions or comments.
Please also rate my answer positively (three or more stars).
Best wishes going forward to you guys and a speedy, full recovery.