Chest/Heart location squeezing/burning feeling

Over the past 2.5 years during exercise when my HR is above 133BPM I am experiencing the feeling of squeezing/burning feeling in the same spot of my left chest. I have had every CAT scan, 2 stress tests, echos, blood work, etc…(many visits with cardiologist, pulmonologist, ENT, etc…)now I am on an acid reflux med!!!!???!!
Blockages have been ruled out by a CATH procedure thru my wrist yesterday because of a positive stress test!
This is the result of my recent extensive ECHO back in January: ‘Left ventricle is smaller than normal. Mildly increased wall Ventricle thickness. Findings consistent with concentric hypertrophy.
Normal systolic function with an estimated EF of 55 - 60%.
Grade 2 diastolic function. Elevated left ventricular filling pressure.’
Still having the squeezing, any thoughts? Thanks.
Mmc