Antianginal Drugs

Antianginal Drugs

1. Definition & scope

• Antianginal drugs are agents that prevent, abort or terminate attacks of angina pectoris (KDT 8e Ch.40, p.584).
• Angina pectoris is chest pain (a heavy, pressing substernal discomfort, rather than true "pain") arising from accumulation of metabolites when there is an imbalance between myocardial O₂ supply and O₂ demand; the term literally means a "strangling feeling in the chest" (G&G 14e Ch.31, p.608; Katzung 16e Ch.12, p.200).
• Typical pain radiates to the left shoulder, flexor aspect of the left arm, jaw or epigastrium; women, the elderly and diabetics more often present with atypical symptoms (G&G 14e Ch.31, p.608).
• Ischemic heart disease (IHD) spans pathologies causing myocardial ischemia (reversible cell injury) through to myocardial infarction (irreversible necrosis) (G&G 14e Ch.31, p.607).
• Myocardial ischemia may be silent — ECG/echo/radionuclide evidence without symptoms; β blockers are more effective than Ca²⁺ channel blockers at preventing silent ischemic episodes, but abolishing all silent ischemia confers no extra benefit over conventional therapy (G&G 14e Ch.31, pp.608–609).