WITH CAUTION - Cardiology Update FK UNAND

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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
Nitrates Tolerance
" Decrease in the effect of a drug
when administered in a long-acting form"
• 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
Nitrates Contraindications
•
•
•
•
Previous hypersensitivity
Hypotension ( < 80 mmHg)
AMI with low ventricular filling pressure
1st trimester of pregnancy
WITH CAUTION:
ž
ž
ž
Constrictive pericarditis
Intracranial hypertension
Hypertrophic cardiomyopathy
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 Effect
Endocardial blood flow
Collateral
Wall tension
Heart rate
Contractility
Cardiac work
Nitrate
B-Blocker
CCB
↑↑
↑
↑
↑↑
→
↑↑
↓
→↑
↓
↑ (reflex)
↓↓
↑↓
↑ (reflex)
↓↓
↓→↑
↓↓
↓↓
↓↓
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...
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