Class I indication for oral nitrate therapy:
- chronic systolic HF + NYHA Class II - IV symptoms + stable angina pectoris refractory to treatment with one antianginal drug.

Class IIa indication for oral nitrate therapy:
- chronic systolic HF + NYHA Class II - IV symptoms + stable angina pectoris + poor tolerance of B-blockers.

Class IIb indication for oral nitrate therapy:
- chronic systolic HF + NYHA Class II - IV symptoms + stable angina pectoris refractory to treatment with two antianginal drugs.