Drug treatments for cardiovascular disease 1 Flashcards
Ischaemic heart disease
Narrowing of lumen of coronary arteries resulting in imbalance between supply of oxygen and myocardial demand resulting in myocardial ischaemia and chest pain
Regulation of cardiac workload
End diastolic volume regulated by sympathetic system, RAAS (contractility of venules), RAAS (Na+ and H2O retention)
Heart rate (sympathetic system/ Ca2+)
Contractility (sympathetic system/ Ca2+)
Total peripheral resistance (sympathetic system, RAAS)
Stable angina
A predictable pattern of pain during exercise that is relieved by rest
Side effects of nitrates
Postural hypotension
Reflex tachycardia
Headache
Dizziness
Reflex tachycardia
Due to activation of sympathetic nervous system
If treatment causes this, look to block effects of SNS using a beta blocker (atenolol)
Beta blockers
Decrease frequency and force contraction
Decreased cardiac output
Inhibit renin release from kidney so inhibit RAAS
Side effects of beta blockers
Bronchoconstriction
Fatigue
Contraindicated in patients with peripheral vascular disease
Bisoprolol
Ca2+ channel antagonists
Decrease frequency and force contraction (phenylalkylamines/ benzothiazepines)
Increase dilation in arterioles (dihydropyridines)
Decrease cardiac workload
Ivabradine
Blocks the pacemaker current in the nodal tissue of the heart (blocks Na+ entry)
Side effects:
- luminous phenomena in retina
- blurred vision
- dizziness
Alternatives
Long acting nitrates (isosorbide mononitrate)
- decrease preload
Nicorandil
- decreases afterload
Ranolazine
- reduces work done by the heart
Trimetazidine
- rebalances energy metabolism in the cell
Treatment to reduce hypocholesterolaemia secondary prevention
Drugs designed to either inhibit uptake from GI tract or reduce production in liver
Frontline treatment are statins
- simvastatin
- atorvastatin
Statins
Decrease production of cholesterol in liver by inhibiting the HMG CoA enzyme
Stimulates liver cells to express LDL receptors and allows liver cells to scavenge LDL cholesterol from plasma
Further secondary prevention
Aspirin
- antiplatelet agents
- aspirin/ clopidogrel
ACE inhibitors
- decrease the workload on the heart
- ramipril
ARBs
- decrease the workload on the heart
- losartan
Mechanism of action of prasugrel
Rapid absorption after oral ingestion
Hydrolysis by esterases
Oxidation by cytochrome P-450
Active metabolite binds to ADP P2Y receptor
Platelet activation decreased
Diagnosis of myocardial infarction
Pain
Sweating, tachycardia, cold clammy skin