CORONARY ARTERY DISEASE Year 4 Internal Medicine Notes

CORONARY ARTERY DISEASE Year 4 · Internal Medicine Collection: 4TH YEAR ALL NOTES / IMED / IMED 4.2 / Ngugi -- Slide 1 CORONARY ARTERY DISEASE JAEL CHEPKOECH FREDRICK MUGAMBI Slide 2 This is the most common form of heart disease.\nIn 2018, CAD accounted for 2.95% of total deaths in Kenya. CAD is almost always due to atherosclerosis and its complications, particularly thrombosis. Rarely it can occur due to aortatitis, vasculities or autoimmune connective tissue disorders. INTRODUCTION Slide 3 Def - thickening of intima due to plaque formation in medium and large sized vessels. It is a progressive inflammatory disorder characterized by focal lipid rich deposits of atheroma that remain clinically silent until they become large enough to impair arterial perfusion or until disruption of the lesion results in thrombotic occlusion or embolization of the affected vessels.\n This commonly occurs in abdominal, popliteal and coronary arteries. Atherosclerosis Slide 4 Non - Modifiable Age Gender Genetic predisposition Modifiable - smoking, DM, hypercholesterolemia, hypertension RISK FACTORS Slide 5 Stenosis - Results in angina, Peripheral artery disease (popliteal A) and Ischemic bowel disease (abdominal A). Plaque rupture with thrombosis - Myocardial infarction or Stroke (MCA) Plaque rupture with embolization... Aneurysm - secondary to weakening of the vessel wall. Complications Slide 6 Coronary Artery Disease clinically manifests as\nSTABLE ANGINA UNSTABLE ANGINA MYOCARDIAL INFARCTION HEART FAILURE ARRYTHMIAS SUDDEN DEATH CAD CONT.. Slide 7 This is a symptom complex caused by transient myocardial ischaemia. It occurs when there is an imbalance between myocardial oxygen supply (coronary blood flow) and demand (cardiac work). ETIOLOGY Coronary atheroma - commonly Others - aortic valve disease, hypertrophic cardiomyopathy etc. STABLE ANGINA Slide 8 Atherosclerosis is the most common cause\n Coronary artery spasm Other causes- aortic stenosis, hypertrophic obstructive cardiomyopathy, aortitis. Pathogenesis of stable angina Slide 9 Clinical features Central chest pain Discomfort and breathlessness that is precipitated by exertion aand is promptly relieved by rest. Some patients experience ‘warm up angina’ -discomfort when they start walking and that later does not return despite greater effort. Slide 10 Canadian cardiovascular society Angina Score. Used to document severity of angina and to assess prognosis. Four classes: Class I- angina only during strenous or prolonged physical activity Class II - slight limitation, with angina only during vigorous physical activity Class III - moderate limitation where symptoms occur with everyday activities. Class IV- inability to perform any activity /angina at rest. Slide 11 HISTORYFor pain SITE- Central chest pain CHARACTER- Tight/squeezing/choking RADIATING- Jaw/neck/shoulder/arm/back ALLEVIATING FACTORS- Rest and Nitrates EXACERBATING FACTORS- Exertion and emotion ASSOCIATED FEATURES- Breathlessness DIAGNOSIS Slide 12 HISTORY RISK FACTORS should be considered. HYPERTENSION DIABETES Smoking Sedentary lifestyle\nObesity /hypercholestrolaemia Haemostatic factors- platelet activation and high plasma fibrinogen Age and gender- disease rates lower in pre-menopausal women, HRT associated with increased risk. DIAGNOSIS Slide 13 PHYSICAL EXAMINATION Usually unremarkable. Look for evidence of; Aortic Valve Disease (Murmurs, shortness of breath particularly when lying down) Left ventricular dysfunction( cardiomegaly, gallop rhythm)\nManifestations of arterial disease\nOther conditions that may exacerbate angina ( anemia, thyrotoxicosis). DIAGNOSIS Slide 14 Baseline tests - FBC, TFTs, Lipid profile, RBS... Stress testing and non invasive imaging usually done to assess extent of CAD Exercise ECG - first line. Performed using a treadmill/ bicycle ergometre protocol while monitoring patient’s pulse, BP and general condition. Downsloping or planar ST segments indicative of ischemia. Amount of exercise that can be tooerated and the extent of ST segment change may be used to assess severity. INVESTIGATIONS Slide 15 Further myocardial imaging or stress echocardiography is indicated if the exercise ECG is normal or inconclusive. CT Coronary arteriography is increasingly gaining use to document presence or absence of CAD. Coronary angiography - usually performed when coronary artery bypass graft surgery or percutaneous coronary intervention is being considered. Slide 16 Principles of management:\nCarefully assess the likely extent and severity of arterial disease Identify and control risk factors e.g. smoking, hypertension, etc. Control symptoms using drugs. Identify high-risk patients for treatment to improve life expectancy MANAGEMENT Slide 17 PHARMACOLOGICAL THERAPY. Anti-platelet therapy Low dose Aspirin (75mg)- reduces risk of getting MI. Clopidogrel (75mg daily)- alternative for those that experience dyspepsia with aspirin. MANAGEMENT Slide 18 Anti-anginal therapy\nNitrates eg GTN (glyceryl tri