Medical Therapy for Relief of Symptoms 4.4.3.1. Use of Anti-ischemic Medications: Recommendations Class I 1. Beta blockers should be prescribed as initial therapy for relief of symptoms in patients with SIHD.757,765,766 (Level of Evidence: B) 2. Calcium channel blockers or long-acting nitrates should be prescribed for relief of symptoms when beta blockers are contraindicated or cause unaccept- able side effects in patients with SIHD.420,768,769 (Level of Evidence: B) 3. Calcium channel blockers or long-acting nitrates, in combination with beta blockers, should be pre- scribed for relief of symptoms when initial treatment with beta blockers is unsuccessful in patients with SIHD.420 (Level of Evidence: B) 4. Sublingual nitroglycerin or nitroglycerin spray is recommended for immediate relief of angina in patients with SIHD.843 845 (Level of Evidence: B) Class IIa 1. Treatment with a long-acting nondihydropyridine calcium channel blocker (verapamil or diltiazem) instead of a beta blocker as initial therapy for relief of symptoms is reasonable in patients with SIHD.420 (Level of Evidence: B) 2. Ranolazine can be useful when prescribed as a substitute for beta blockers for relief of symptoms in patients with SIHD if initial treatment with beta blockers leads to unacceptable side effects or is ineffective or if initial treatment with beta blockers is contraindicated.846 (Level of Evidence: B) 3. Ranolazine in combination with beta blockers can be useful when prescribed for relief of symptoms when initial treatment with beta blockers is not successful in patients with SIHD.847,848 (Level of Evidence: A) 4.4.3.1.1. Beta Blockers. Beta blockers are recommended as the initial agents to relieve symptoms in most patients with SIHD. Beta blockers reduce myocardial oxygen consumption by reducing heart rate, myocardial contractility, and afterload, with attenuation of cardiovascular remodeling by decreasing LV wall tension with long-term use. 