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FAMILY MEDICINE COURSE (FAM530) CV Risk factors & IHD. Presented by :. Learning objective. At the end of this session, the student will be able to: Discuss the differential diagnosis of a patient presented with chest pain.
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FAMILY MEDICINE COURSE (FAM530) CV Risk factors & IHD Presented by :
Learning objective • At the end of this session, the student will be able to: • Discuss the differential diagnosis of a patient presented with chest pain. • Describe the current epidemiology of coronary artery disease (CHD). • Identify major and minor risk factors for coronary heart disease. • Utilize the Framingham formula to predict future cardiovascular risk. • Recognize the available diagnostic tests for CHD, including the scientific foundations underlying each test, advantages and disadvantages, risks, and benefits. • Describe lifestyle and pharmacological interventions for treating CHDrisk factors, as well as CHD itself.
Case Scenario A 52-year-old, business man, presents with 7 months H/o mild chest pain of no specific character. Sometimes brought by exertion but could be felt on rest. PMH: unremarkable Non-smoker Bp: 124 / 82 mmHg BMI: 23 kg/m² FH: - his father died at age of 54 by heart attack - His elder brother had CABG at age of 48 FPG: 5.1 mmol/l (91.8 mg/dl ) T. Cholesterol: 4.6 mmol/L ( 82.8 mg/dl ) LDL.C: 2.57 mmol/l ( 46.26 mg/dl ) HDL.C: 1.09mmol/l (19.62 mg/dl ) Trig.: 1.74 mmol/L ( 31.31mg/dl ) ECG: Normal
Ihd overview • Ischemic heart disease (IHD) is defined as an imbalance between cardiac blood supply ( perfusion ) and myocardial oxygen demand resulting in Myocardial Ischemia.
Epidemiology The Leading Causes of Death From Cardiovascular Disease Data from American Heart Association, 2006.
Epidemiology Globally, there is an uneven distribution of age-adjusted CVD mortality. The lowest age-adjusted mortality rates are in the advanced industrialized countries and parts of Latin America, whereas the highest rates today are found in Eastern Europe and a number of low and middle income countries. Overall, age-adjusted CVD death rates are today higher in major low and middle income countries than in developed countries. (WHO, 2008b).
Globally, there is an uneven distribution of age-adjusted CVD mortality. Age-standardized deaths due to cardiovascular disease (rate per 100,000), 2004
Cardiovascular diseases in KSA: the third most common cause of hospital-based mortality second to accident and senility. (35 percent) were due to cardiovascular disease. Vascular injury accumulates in adolescence, making it necessary for primary preventive measures to be taken from childhood. WHO report, 2008
Clinical manifestations of Ihd • 1) An acute coronary syndrome (ACS) which includes • unstable angina • non–ST-segment elevation MI • ST-segment elevation MI • 2) Chronic stable exertional angina • 3) Asymptomatic: ischemia due to coronary artery vasospasm (variant or Prinzmetalangina). • 4) Arrhythmia • 5) Heart failure • 6) Sudden death
Causes Ischemia can result from : 1) Increase oxygen demand (e.g. increase heart rate or hypertension ) 2) Diminished oxygen-carrying capacity (e.g. anemia or carbon monoxide poisoning) 3) In the vast majority of IHD cases is relatively due to coronary atherosclerosis that begins early in life but manifests only after the vascular occlusions reach a critical stage.
Atherosclerosis pathogenesis video http://www.youtube.com/watch?v=fLonh7ZesKs
Manifestations of Atherosclerosis • : Heart • Myocardial Ischemia • Angina • Myocardial Infarction • : Brain • Transient ischemic attack (TIA) • Cerebrovascular accident (stroke) • Legs: • Intermittent claudication
Manifestations of Atherosclerosis Myocardial Ischemia : -LV stiffening & decreased diastolic filling (diastolic dysfunction) - Impaired LV systolic emptying - ECG changes associated with altered repolarization - Angina Pectoris : transient, referred cardiac pain resulting from ischemia
Manifestations of Atherosclerosis Angina : Angina pectoris - Symptom not a disease - Chest discomfort associated with abnormal myocardial function in the absence of myocardial necrosis
Manifestations of Atherosclerosis • Characteristics of “typical” or “classic” • - Pressure, tightness, squeezing, heaviness, or choking • - Radiates down left arm, back, and/or jaw • - Occurs with physical activity, emotional stress, cold weather, heavy meals • - Last few minutes ( 15sec to 15 min) or until activity ceases • -May be relieved by rest or nitroglycerine. • -May be associated with nausea, vomiting, or diaphoresis
Manifestations of Atherosclerosis Angina – Types: Silent ischemia: no pain stable or typical angina :chest pain associated with exertion or some other forms of stress. Usually relieved by rest or sublingual nitroglycerin Unstable Angina: Pain occurs with progressively increasing frequency, is precipitated by less exertion, even at rest, and tends to be of more prolonged duration. Unstable angina is often the precursor of subsequent acute MI. Thus this referred to as pre-infarction angina. Variant prinzmetal angina: uncommon pattern that occurs at rest and is due to coronary artery spasm and not related to atherosclerotic disease.
Manifestations of Atherosclerosis Myocardial Infarction Diagnosis: 2 of 3 criteria: 1) Chest pain > 30 minutes 2) ECG: - ST segment elevation - T wave intervention 3) Cardiac enzymes: -Creatinephosphokinase (CK) Normal = 0-195 -Troponin T – Normal < 0.03
Manifestations of Atherosclerosis Myocardial Infarction • Signs & Symptoms: • - Angina • - GI upset • - Dyspnea • - Diaphoresis • - Syncope
Nob-modifiable risk factors Family History Twice the risk of MI if one first-degree relative with MI Triple the risk of MI if 2+ first-degree relatives with MI Risk is strongest if MI occurred at age 55 or less Advancing Age Increases with age Gender Men >pre menopausal women Men = post menopausal women
dyslipidemia Much research to support the link between abnormal serum lipid levels and CAD LDL = risk of CAD HDL = risk of CAD TGs = risk of CAD Abnormal lipid levels are known to be the basis of the atherosclerotic process
dyslipidemia Lipid Targets for CAD Primary Targets: The previous guidelines recommended treating to an LDL goal of below 100 mg/dL in people at high cardiovascular risk, but also recommended a goal of 70 mg/dL or lower for patients at very high risk.
dyslipidemia Other factors : Metabolic syndrome can be a secondary target of risk reduction after LDL-C has been addressed. This syndrome is characterized by Abdominal Obesity: Weight Circumference Men ≥ 102 cm Women ≥ 88 cm Triglycerides ≥ 1.7 mmol/L (150 mg/dL) Or on medication HDL cholesterol men < 1.05 mmol/L (40 mg/dL) women < 1.30 mmol/L (50 mg/dL) Or on medication for HDL-C Blood Pressure ≥ 130/85 or on antihypertensive Medication Fasting Glucose ≥ 100 mg/dl (5.6 mmol/L) or any medication for high blood glucose
Hypertension - Primary risk factor for CAD - Hypertension is associated with three to four times increased risk for CAD, MI & PVD
diabetes People with diabetes have 2 to 7 times increased risk of developing CAD than people without diabetes Endothelial damage - Increased platelet aggregation - Insulin promotes synthesis of lipids and uptake of lipids by smooth muscle Excess sugar in vessels damages the lining making it vulnerable to plaques and clots
diabetes Careful control of blood sugar levels reduces the risk of developing the complications of diabetes
Tobacco smoking - More in men. - Declines to almost normal after 10 years of abstention How Does Smoking Increase CAD Risk? Increased HR and BP Increased vasoconstriction Decreased HDL Increased LDL and Triglycerides Increased LDL oxidation Increased platelet aggregation Decreased O2 carrying capacity
obesity Risk in central obesity > peripheral obesity. Obesity is often associated with - Diabetes - Hypertension - Dyslipidemia - Inactivity
obesity • Waist Circumference • - ACSM Waist Circumference Targets Body Mass Index (BMI) - Measured in Kg/m2 -ACSM BMI Targets
Sedentary lifestyle Physical activity reduces the risk of CAD through: - Improved balance between myocardial O2 supply and demand - Decreased platelet aggregation - Decreased susceptibility to malignant ventricular arrhythmias - Improved endothelial tone - Beneficial effect on other CAD risk factors (ie. diabetes, dyslipidemia, hypertension, obesity, stress)
Psychosocial factors Work stress Lack of social support Depression Anxiety Type A personality
Psychosocial factors Influence CAD risk via : Catacholamine release - Increased BP & HR - Vasoconstriction - Increased O2 demand
Other risk factors • Drugs (contraceptive pill, nucleoside analogues) • Heavy alcohol consumption • Poor oral health • Diets ( High in fats and low in antioxidant) • Infectious agents • High levels of coagulation factors – high fibrinogen, factor VII • Elevated C-reactive protein (inflammatory marker)
What is happening to the prevalence of risk factors ? Mortality rates for heart disease have steadily declined in the US. These declines are related to improvements in some risk factors: • Improved treatments for hypertension and hyperlipidaemia. • Increase community awareness • Declines in smoking Increases in obesity and diabetes may threaten this decline in the future.
Framingham Cardiovascular Risk Calculation Framingham Cardiovascular Risk Calculator, uses recent data from the Framingham Heart Study to estimate 10-year risk for coronary heart disease outcomes (myocardial infarction and coronary death). It is designed to estimate risk in adults aged 20 and older who do not have heart disease or diabetes The various degrees of risk associated with five categories: • AGE • TOTAL CHOLESTEROL LEVEL • HDL-C LEVEL • SMOKING • Systolic Bp
For persons without known CHD, other forms of atherosclerotic disease, or diabetes: Count the number of risk factors. Use Framingham scoring for persons with 2 risk factors to determine the absolute 10-year CHD risk. • Assessment of Risk For persons with 0–1 risk factor, Framingham calculations are not necessary.
NOTE: Cardiovascular risk calculator should not be used if - BP >185 or <100 mmHg - total cholesterol >8mmol/l (144mg/dl ). Estimated risks do not allow for factors such as family history and this should be borne in mind.
Case Scenario A 52-year-old, business man, presents with 7 months H/o mild chest pain of no specific character. Sometimes brought by exertion but could be felt on rest. PMH: unremarkable Non-smoker Bp: 124 / 82 mmHg BMI: 23 kg/m² FH: - his father died at age of 54 by heart attack - His elder brother had CABG at age of 48 FPG: 5.1 mmol/l (91.8 mg/dl ) T. Cholesterol: 4.6 mmol/L ( 82.8 mg/dl ) LDL.C: 2.57 mmol/l ( 46.26 mg/dl ) HDL.C: 1.09mmol/l (19.62 mg/dl ) Trig.: 1.74 mmol/L ( 31.31mg/dl ) ECG: Normal
Assessment of Risk Step 1: Age MEN WOMEN Expert Panel on Detection, Evaluation, and Treatment of High BloodCholesterol in Adults. JAMA. 2001;285:2486-2497.
Step 2: Total Cholesterol Men Women
Assessment of Risk Step 3: HDL- Cholesterol Men Women
Assessment of Risk Step 4: Systolic Blood Pressure Men Women
Assessment of Risk Step 5: smoking status Men Women
Assessment of Risk Step 6: adding up the points (Sum From Steps 1–5)