Hi,
Few lab work needed are ECG, echocardiograpgy, 
lipid profile, these tests will tell further treatment options to be done, as a supporter your 
heart rate can naturally be low, it is common but for variation you must go to physician. For long term help keep check on lipid profile also. There are some other options which are in generalized helpful are, do some deep 
breathing exercise [art of living sahaj samadhi workshop], it shows good results in patients with similar history. Diet should be simple [vegetables, salads, lots of fruits, 7-8 glasses lots of water]. Avoid going near area of 
smoking, caffeine, alcohol, canned products are avoided.
Take care. Hope I have answered your question. Let me know if I can assist you further.
Regards,
Dr. Sunny Madar, General & Family Physician