Hello There,
PPIs (Proton Pump Inhibitors) are usefull in the Hyperacidity or GERD (Gastro esophageal Reflux disease) to reduce the acidity. In your case if you are taking PPIs for chest tightness and it really gives you relief then your Chest tightness might be due to GRRD as a associated symptom.
You may stop taking PPIs if you feel better now. You may start them anytime if you feel same problem again.
Next Steps
Visit to Physician if problem aggravates. ECG test must be done with Physician's consult.
Health Tips
Take PPIs 30 minutes before meal or an empty stomach early in the morning for better effect.