New Paradigm of Anti Anginal Therapy

dr.Yerizal Karani SpPD,SpJP(K)

Angina Pectoris• Angina pectoris sudden severe pressing

chest pain or heaviness radiating to the neck, jaw, back and arms associated with diaphoresis, tachypnea and nausea.

• Angina insufficient coronary flow to meet oxygen demands of the myocardium precipitated by any activity/process that creates an imbalance in O2 supply and demand

Types of Angina

• Angina occurs in three overlapping patterns:– Stable angina– Unstable angina– Prinzmetal (variant)

angina

Nitrat

• Nitrogliserin (gliseril trinitrat) very fast onset sublingually acute condition

• Isosorbide dinitrate fast onset sublingually (substitute of gliseril trinitrat)

• Isosorbide mononitrate slow onset used in preventing angina

" Decrease in the effect of a drugwhen administered in a long-acting form"

Nitrates Tolerance

• Develops with all nitrates

• Is dose-dependent

• Disappears in 24 h. after stopping the drug

• Tolerance can be avoided– Using the least effective dose

– Creating discontinuous plasma levels

WITH CAUTION:� Constrictive pericarditis� Intracranial hypertension� Hypertrophic cardiomyopathy

Nitrates Contraindications• Previous hypersensitivity• Hypotension ( < 80 mmHg)• AMI with low ventricular filling pressure • 1st trimester of pregnancy

Contraindication B-Blocker

• Hypotension: BP < 100 mmHg

• Bradycardia: HR < 50 bpm

• Chronic bronchitis, ASTHMA

• Severe chronic renal insufficiency

Reasons for Using Nitrates and Beta Blockers in Combination in Angina

• Beta Blockers prevent reflex tachycardia and contractility produced by nitrate-induced hypotension.

• Nitrates prevent any coronary vasospasm produced by Beta Blockers.

• Nitrates prevent increases in left ventricular filling pressure or preload resulting from the negative inotropic effects produced by Beta Blockers.

• Nitrates and Beta Blockers both reduce myocardial oxygen consumption by different mechanisms.

• Nitrates and Beta Blockers both increase subendocardial blood flow by different mechanisms

Anti Anginal EffectNitrate B-Blocker CCB

Endocardial blood flow ↑↑ ↑ ↑

Collateral ↑↑ → ↑↑

Wall tension ↓ →↑ ↓

Heart rate ↑ (reflex) ↓↓ ↑↓

Contractility ↑ (reflex) ↓↓ ↓→↑

Cardiac work ↓↓ ↓↓ ↓↓

Take Home Messages

• Angina pectoris imbalance of O2 in supply & demand of the myocardium

• Nitrogliserin: very fast onset of nitrate in angina pectoris

THANK YOU...