Ischaemic heart disease of the heart.pptx

Ischaemic heart disease also called angina pectoris is a disorder affecting the heart muscle

1. ISCHAEMIC HEART DISEASE Kyambadde Bonny Bpharm (MUK)

2. Defn A condition in which there is insufficient blood flow through the coronary arteries of the, thus leading to ischaemia and/ or infarction

3. Epidemiology Men die earlier from IHD and acute myocardial infarction than women A ging of both sexes is associated with a higher incidence of these afflictions The presenting manifestation in women is more commonly angina, whereas men more frequently have myocardial infarction as the initial event

4. Pathopysiology Ischaemic heart disease is nearly always caused by atheroma in one or more of the coronary arteries. is often asymptomatic When the obstruction caused by an uncomplicated atheromatous plaque exceeds a critical value, myocardial oxygen demand during exercise exceeds the ability of the stenosed vessel to supply oxygenated blood, resulting in chest pain brought on predictably by exertion and relieved within a few minutes on resting (‘angina pectoris’) . Treatment of patients with ischaemic heart disease is directed at the three pathophysiological elements identified above , namely atheroma, haemodynamics and thrombosis.

5. Classification of angina Stable angina Most patients with angina pectoris experience attacks of pain in a constant stable pattern Unstable angina A ttacks occur at rest , or they may occur with increasing frequency and severity on less and less exertion

6. MANAGEMENT OF STABLE ANGINA GOALS OF THERAPY The short-term goals of therapy for ischemic heart disease are to reduce or prevent the symptoms of angina that limit exercise capability and impair quality of life. Long -term goals of therapy are to prevent CHD events such as myocardial infarction, arrhythmias , and heart failure and to extend the patient’s life. Because there is little evidence that revascularization procedures such as angioplasty and coronary artery bypass surgery extend life, the primary focus should be on altering the underlying and ongoing process of atherosclerosis through risk factor modification while providingsymptomatic relief through the use of nitrates, β-blockers, calcium channel blockers, and ranolazine for anginal symptoms.

7. MODIFIABLE RISK FACTORS Modifiable risk factors include smoking, hypertension, hypercholesterolaemia , diabetes mellitus, obesity and lack of exercise. The object of defining these factors is to improve them in individual patients, thereby preventing progression (and hopefully causing regression) of coronary atheroma

8. PAIN RELIEF An attack of angina is relieved by glyceryl trinitrate (GTN) , which is given by sublingual administration. However, in patients with chronic stable angina, pain usually resolves within a few minutes of stopping exercise even without treatment , so prophylaxis is usually more important than relief of an attack . In patients hospitalized with acute coronary syndrome , GTN is often administered by intravenous infusion; its short half- life allows rapid titration, thus permitting effective pain relief whilst promptly averting any adverse haemodynamic consequences (in particular, hypotension).

9. PROPHYLAXIS Antithrombotic therapy with aspirin reduces the incidence of myocardial infarction GTN is best used for ‘ acute’ prophylaxis . A dose is taken immediately before undertaking activity that usually brings on pain Alternatively, long-acting nitrates ( e.g. isosorbide mononitrate ) may be taken regularly to reduce the frequency of attacks Beta-blockers (usually of the ‘ cardioselective ’ type , e.g. atenolol , metoprolol or bisoprolol ) or calcium -channel blockers (most commonly diltiazem , less commonly verapamil or one of the dihydropyridine drugs ,such as nifedipine or amlodipine) are also useful for chronic prophylaxis Statins (e.g. S imvastatin or atorvastatin) should be prescribed routinely for cholesterol lowering unless there is a contraindication

10. CONSIDERATION OF SURGERY/ANGIOPLASTY Cardiac catheterization identifies patients who would benefit from coronary artery bypass graft (CABG) surgery or percutaneous coronary intervention (PCI, which most commonly involves balloon angioplasty of the affected coronary arteries with concomitant stent insertion). Coronary artery disease is progressive and there are two roles for such interventions: 1. symptom relief; 2. to improve outcome

11. ACUTE CORONARY SYNDROME Acute coronary syndrome (ACS) is a blanket term used to describe the consequences of coronary artery occlusion , whether transient or permanent, partial or complete These different patterns of coronary occlusion give rise to the different types of ACS, namely unstable angina (where no detectable myocardial necrosis is present), non- ST segment elevation myocardial infarction (NSTEMI) and ST segment elevation myocardial infarction (STEMI, usually larger in extent and fuller in thickness of myocardial wall affected than NSTEMI ) MANAGEMENT OF UNSTABLE CORONARY DISEASE

12. CONT … Patients with ACS require urgent antiplatelet therapy, in the form of aspirin and clopidogrel (Chapter 30), plus antithrombotic therapy with heparin (nowadays most often lowmolecular -weight heparin administered subcutaneously This antiplatelet/ antithrombotic regime approximately halves the likelihood of myocardial infarction By contrast, GTN , while very effective in relieving pain associated with unstable angina , does not improve outcome A β -blocker is prescribed if not contraindicated If β-blockers are contraindicated , a long-acting Ca2-antagonist is a useful alternative. Diltiazem is often used as it does not cause reflex tachycardia and is less negatively inotropic than verapamil . Coronary angiography is indicated in patients who are potentially suitable for PCI or CABG, and should be considered as an emergency in patients who fail to settle on medical therapy.

13. ST-ELEVATION- MYOCARDIAL INFARCTION ( STEMI) ACUTE MANAGEMENT Oxygen This is given in the highest concentration available ( unless there is coincident pulmonary disease with carbon dioxide retention ) delivered by face mask (FiO2 approximately 60%) or by nasal prongs if a face mask is not tolerated . Pain relief This usually requires an intravenous opiate (morphine or diamorphine ; see Chapter 25) and concurrent treatment with an anti-emetic (e.g. promethazine or metoclopramide)

14. Cont.. Infarct limitation In centres where immediate access is available to the cardiac catheterization laboratory, the treatment of choice for limitation of infarct size and severity is generally considered to be primary angioplasty Consideration of surgery

15. DRUGS USED IN ISCHAEMIC HEART DISEASE DRUGS THAT INFLUENCE HAEMODYNAMICS ORGANIC NITRATES β-ADRENOCEPTOR ANTAGONISTS ANGIOTENSIN -CONVERTING ENZYME INHIBITOR ( ACEI) AND ANGIOTENSIN RECEPTOR BLOCKERS CALCIUM ANTAGONISTS DRUGS THAT INFLUENCE THROMBOSIS ASPIRIN CLOPIDOGREL

16. FIBRINOLYTIC DRUGS Streptokinase Alteplase Reteplase Tenecteplase DRUGS THAT ARE USED TO INFLUENCE ATHEROSCLEROSIS

17. For each drug/drug class MOA Contraindications Adverse effects Pks Drug interactions

18. END