Ischemic Heart Disease PDF

College of Pharmacy Fourth year. Clinical Pharmacy Cardiovascular disorders Ischemic Heart Disease Introduction 1-Ischemic heart disease (IHD) is defined as lack of oxygen and decreased or no blood flow to the myocardium resulting from coronary artery narrowing or obstruction. 2-It may present as ac...

College of Pharmacy Fourth year. Clinical Pharmacy Cardiovascular disorders Ischemic Heart Disease Introduction 1-Ischemic heart disease (IHD) is defined as lack of oxygen and decreased or no blood flow to the myocardium resulting from coronary artery narrowing or obstruction. 2-It may present as acute coronary syndrome (ACS) [which includes unstable angina and non–ST-segment elevation (NSTE) or ST-segment elevation (STE) myocardial infarction (MI)], chronic stable exertional angina, ischemia without symptoms, microvascular angina, or ischemia due to coronary artery vasospasm (variant or Prinzmetal angina). Pathophysiology 1-Angina pectoris usually results from increased myocardial oxygen demand in the setting of a fixed decrease in myocardial oxygen supply because of atherosclerotic plaque. 2-Coronary plaques that occupy less than 50%–70% of the vessel luminal diameter rarely produce ischemia or angina. However, smaller plaques have a lipid-rich core and thin fibrous cap and are more prone to rupture and cause acute thrombosis. 3-When the luminal diameter of epicardial vessels is reduced by 70% or more, minimal physical exertion may result in a flow deficit with myocardial ischemia and often angina. 4-Patients with variant (Prinzmetal) angina usually do not have a coronary flowobstructing plaque but instead have significant reduction in myocardial oxygen supply due to vasospasm in epicardial vessels. Clinical presentation 1-Patients typically complain of chest pain precipitated by exertion or activities of daily living that is described as squeezing, crushing, heaviness, or chest tightness. It can also be more vague and described as a numbness or burning in the chest. 2-The location is often substernal and may radiate to the right or left shoulder or arm (left more commonly), neck, back, or abdomen. Ischemic symptoms may be associated with diaphoresis, nausea, vomiting, and dyspnea. 3-Chest pain generally lasts from 5 to 20 minutes and is usually relieved by rest or sublingual nitroglycerin (SL NTG). 4-Some patients (especially women and older individuals) present with atypical chest pain. Patients with diabetes mellitus may have decreased pain sensation due to neuropathy. 5-Patients with variant (Prinzmetal) angina are typically younger and may present with chest pain at rest, often early in the morning. 1 Diagnosis 1-Obtain the medical history to identify the quality and severity of chest pain, precipitating factors, location, duration, pain radiation, and response to nitroglycerin or rest. 2-Assess nonmodifiable risk factors for coronary artery disease (CAD): age, sex, and family history of premature atherosclerotic disease in first degree relatives (male onset before age 55 or female before age 65). 3-Identify the presence of modifiable CAD risk factors: hypertension, diabetes mellitus, dyslipidemia, and cigarette smoking. 4-Cardiac troponin concentrations are not typically elevated in stable IHD. 5-Resting ECG is normal in at least half of patients with angina who are not experiencing acute ischemia. About 50% of patients develop ischemic ECG changes during an episode of angina, which can be observed on the ECG during an exercise stress test. 6-Coronary angiography is the most accurate test for confirming CAD but is invasive and requires arterial access. Myocardial perfusion imaging, cardiac magnetic resonance, and CT angiography can also be used to detect CAD. Treatment Goals of Treatment: 1-A primary goal of therapy is complete (or nearly complete) elimination of anginal chest pain and return to normal activities. 2-Long-term goals are to slow progression of atherosclerosis and prevent complications such as MI, heart failure, stroke, and death. Nonpharmacologic Therapy 1-Lifestyle modifications include daily physical activity, weight management, dietary therapy (reduced intake of saturated fats, and cholesterol), smoking cessation, psychological interventions (eg, screening and treatment for depression if appropriate), limitation of alcohol intake, and avoiding exposure to air pollution. 2-Surgical revascularization options for select patients include coronary artery bypass grafting (CABG) or percutaneous coronary intervention (PCI) with or without stent placement. Pharmacologic Therapy 1-Guideline-directed medical therapy (GDMT) reduces the rates of death and MI similar to revascularization therapy. 2-Approaches to risk factor modification include the following recommendations: Dyslipidemia: Use moderate- or high-dose statin therapy in addition to lifestyle changes. Addition of ezetimibe (first) or a PCSK9 inhibitor (second) is reasonable for patients who do not tolerate statins or do not attain a 50% decrease in LDL cholesterol (or LDL remains above 70–100 mg/dL). Blood pressure: If BP is ≥130/80 mm Hg, institute drug therapy in addition to or after a trial of lifestyle modifications. 2 Diabetes mellitus: Pharmacotherapy to achieve a target A1C of ≤7% is reasonable for select patients (eg, short duration of diabetes and long life expectancy). An A1C goal of