Revise MBBS

Paper I — 2022 May (Supplementary) (2010 Scheme) — Q2

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Paper I
2022 May (Supplementary) (2010 Scheme) · 40 marks · 120 min

Question

A 60-year-old man gives history of chest pain, sweating and breathlessness on brisk walking, which is relieved on taking rest.  Classify drugs that are useful in this condition.  Explain the mechanism and pharmacological actions, uses and adverse effects of nitrates (2+4)

Q26 marksEssays

Answer

The presentation (exertional chest pain, sweating, breathlessness, relieved by rest) is classic stable (classical) angina — myocardial oxygen supply-demand mismatch on exertion.

Classification of antianginal drugs

ClassExamplesPrimary effect
Organic nitratesGlyceryl trinitrate, Isosorbide dinitrate, Isosorbide mononitrateVenodilation → ↓preload
Beta-blockersPropranolol, Metoprolol, Atenolol↓Heart rate and contractility → ↓O₂ demand
Calcium channel blockersVerapamil, Diltiazem, Amlodipine↓Afterload, coronary vasodilation
Newer/second-lineNicorandil, Ranolazine, Trimetazidine, IvabradineVaried — K⁺-channel opening, late Na⁺-current inhibition, metabolic modulation, If-channel inhibition

Mechanism, actions, uses, and adverse effects of nitrates

  • Mechanism: nitrate → released as nitric oxide (NO) → activates guanylyl cyclase → ↑cGMP → vascular smooth muscle relaxation.
  • Actions: predominant venodilation (↓preload, ↓ventricular wall tension and O₂ demand) at low doses; arteriolar dilation (↓afterload) at higher doses; also dilates large coronary vessels and collaterals, redistributing blood flow toward ischemic subendocardium.
  • Uses: acute anginal attack (sublingual GTN — rapid onset), prophylaxis of exertional angina (longer-acting oral/transdermal nitrates), acute left ventricular failure/pulmonary edema (preload reduction).
  • Adverse effects: throbbing headache (meningeal vasodilation), postural hypotension and reflex tachycardia, flushing, tolerance with continuous use (requires a nitrate-free interval), methemoglobinemia with very high doses.
  • Key interaction: contraindicated within 24 hours of PDE-5 inhibitors (sildenafil and similar) — risk of severe, sometimes fatal, potentiated hypotension.
  1. 1Antianginal Drugs

Other Years Asked

  1. 1Mr. X, a 65-year-old retired teacher had severe retrosternal chest pain radiating to shoulder and left arm. He was profusely sweating and his ECG revealed ST elevation and a diagnosis of Acute Myocardial infarction was made. (2022 February (2019 Scheme)Essay · 15 marks
  2. 2(2022 July (Supplementary) (2019 Scheme)Essay · 9 marks
  3. 3(2024 June (Supplementary) (2019 Scheme)Short Essay · 8 marks
  4. 4Classify drugs used in the treatment of angina pectoris. What is the effect of nitrates on coronary blood flow. Describe the mechanism of action and any two adverse effects of nitrates. (2+1+2+1 =6)2017 February (2010 Scheme)Essay · 6 marks
  5. 5Nicorandil2013 April (2010 Scheme)Short Note · 3 marks
  6. 6Calcium channel blockers2019 July (Supplementary) (2010 Scheme)Short Note · 3 marks
  7. 7Amlodipine2023 March (Supplementary) (2010 Scheme)Short Note · 3 marks
  8. 8Two uses and two adverse effects of calcium channel blockers.2014 September (Supplementary) (2010 Scheme)Short Answer · 1 mark
  9. 9Use of morphine in left ventricular failure2017 February (2010 Scheme)Short Answer · 1 mark
  10. 10Amlodipine and metoprolol in angina2023 July (Supplementary) (2010 Scheme)Short Answer · 1 mark
  11. 11Calcium channel blockers2018 July (Supplementary) (2010 Scheme)Short Answer · 1 mark
  12. 12Rationale of combining beta blockers with long acting nitrates2013 April (2010 Scheme)Short Answer · 1 mark
  13. 13Morphine in Acute myocardial infarction2024 March (Supplementary) (2010 Scheme)Short Answer · 1 mark
  14. 14Glyceryl trinitrate.2025 March (Supplementary) (2010 Scheme)Short Answer · 1 mark
  15. 15Rationale for use of calcium channel blockers in angina2015 September (Supplementary) (2010 Scheme)Short Answer · 1 mark
  16. 16Angina pectoris2013 September (Supplementary) (2010 Scheme)Short Answer · 1 mark
  17. 17Rationale for the use of nitrates in angina pectoris.2014 September (Supplementary) (2010 Scheme)Short Answer · 1 mark
  18. 18Nitrates in acute attack of angina.2016 February (2010 Scheme)Short Answer · 1 mark
  19. 19Isosorbidedinitrate2021 February (Supplementary) (2010 Scheme)Short Answer · 1 mark
  20. 20Mechanism of action of nitrates.2017 August (Supplementary) (2010 Scheme)Short Answer · 1 mark
  21. 21Morphine in Acute left ventricular failure.2025 March (Supplementary) (2010 Scheme)Short Answer · 1 mark
  22. 22Drugs for the prophylaxis of angina pectoris2014 March (2010 Scheme)Short Answer · 1 mark
  23. 23Morphine in Acute left ventricular failure2023 March (Supplementary) (2010 Scheme)Short Answer · 1 mark
  24. 24Two uses and two adverse effect of nifedipine.2016 February (2010 Scheme)Short Answer · 1 mark
  25. 25Sodium nitrite in the treatment of Cyanide poisoning2024 August (Supplementary) (2010 Scheme)Short Answer · 1 mark
  26. 26Beta blockers in angina2020 February (Supplementary) (2010 Scheme)Short Answer · 1 mark
  27. 27Anti anginal agents2024 March (Supplementary) (2010 Scheme)Short Answer · 0.3 marks
  28. 28Drugs used for PSVT2020 February (Supplementary) (2010 Scheme)Short Answer · 0.3 marks

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