The best cure is to know the cause
Heartburn is not caused by too much acid, but because of weak stomach acids. ACV and other digestible acids, like dill pickle juice, can be used to strengthen your stomach acids. The worst thing you can do for heartburn is to take anti acids, for they weaken and already weak stomach acid. Thereby the stomach must produce more acid, which causes acid reflux. So the next time you get heartburn, just take a swig of your favorite pickle juice, and overtime you will discover your problem with heartburn will be a thing of the past.