Can coughing stop a heart attack?

Q: Can coughing stop a heart attack? A doctor told me that it can. Is that true?
Krishna: The moment I saw this I knew this cannot be applied to all heart attacks.
Heart attacks are not the same thing as cardiac arrest.
So here is the expert explanation to 'your doctor's "mythical" advice'.
Can coughing stop a heart attack?
Internet myths have resurrected the idea that coughing can stop a heart attack in its tracks or fix an irregular heart rhythm.
But according to these specialists - Cardiac surgeon A. Marc Gillinov, MD, and cardiologist Steven Nissen, MD, University of Chicago Medicine cardiologist and professor of medicine Matthew Sorrentino, MD:

Heart attacks occur when the heart’s oxygen supply gets cut off, which is usually caused by blockages in the cardiac arteries that feed the heart oxygen-rich blood. When you have a heart attack, tissue in the heart can die. However, your heart usually keeps on beating. Cough CPR is ineffective for heart attacks.

Cardiac arrest is the largest cause of natural death in several parts of the world. During cardiac arrest, your heart can suddenly stop beating and serious irregularity in the heartbeat (arrhythmia) can cause this. You may have a higher risk of cardiac arrest if you had a previous heart attack.

“Cough CPR is an effective way to maintain circulation for a minute or two following cardiac arrest,” says Dr. Nissen. “However, it’s not useful in a patient with a heart attack and shouldn’t delay calling".

Why it doesn’t work most of the time
“Some rhythms could lead to cardiac arrest, that’s why people thought, ‘Oh, if the cough will prevent the cardiac rhythm maybe it will help the cardiac arrest.’” “But most patients that go into cardiac arrest are going to go into a more chaotic rhythm.”

Chaotic rhythms are what prove the method false. Simply coughing will not always correct an irregular chaotic rhythm, and it cannot prevent the patient from going into cardiac arrest.

So what should you do if you’re having a cardiac event or you’re with someone else who is? The best initial response is to call 911 in US (102, 108 or 112 in India) . If you or someone else is properly trained, start CPR and, if available, use an automatic external defibrillator (AED).

Coughing doesn't always help. It's not effective in all patients.

Coughing away a heart attack could delay medical help.

Sources: 

https://www.uchicagomedicine.org/forefront/heart-and-vascular-artic...

https://www.heart.org/en/health-topics/cardiac-arrest/emergency-tre...

https://health.clevelandclinic.org/can-you-cough-away-a-heart-attack/