ECG is a resting evaluation of heart, whereas treadmill TMT give this information on exercise Related Cardiac issues. If physical exertion provokes ischaemia it is considered as positive TMT. If you have other risk factors and symptoms suggestive of CardIAC Illness you should undergo a coronary angiogram either conventional CAG or CTCAG
Next Steps
Lifestyle modification, healthy diet, physical exertion, yoga meditation, avoid addictions if any.