Also there is a close connection between the heart, kidney, kidneys and other organs.
For instance, ACE1 and ACE2 receptors are involved in a complex hormonal system that manages your blood volume, blood pressure, etc. Antihypertensive drugs target this system at different points. (ACE inhibitor drugs such as Lisinopril target the ACE1 receptor and don't bind much to ACE2 at all)
Liver failure can present with symptoms similar to asthma because if your kidneys can't get rid of water, the water will leak out of your lungs.
I had a friend who passed away last year from a bacterial infection that got to his heart. We all have bacteria that live on our skin without problems, but if you get a wound they can get into your blood and go to your heart.
He had heart valve damage which is bad because if your heart valves work improperly, it can damage your blood the way you can 'damage' cream by whipping it. This can cause clots to go into your lungs or your brain with bad results either way.
He had open heart surgery but they had a hard time restarting his heart and he was in a coma for a few months before they removed his feeding tube.
One reason why penicillin was a miracle was that all sorts of people who got even minor wounds (e.g. soldiers, children, farmers, ...) would progress like that before WWII.