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Also called angina pectoris No worries! We‘ve got your back. Try BYJU‘S free classes today! Not common among young ones No worries! We‘ve got your back. Try BYJU‘S free classes today! Enough oxygen does not reach to the heart muscles No worries! We‘ve got your back. Try BYJU‘S free classes today! Right on! Give the BNAT exam to get a 100% scholarship for BYJUS courses Open in App Solution The correct option is B All of the aboveAngina is a condition of acute chest pain that appears when the heart muscles do not receive adequate supply of oxygenated blood. It is also called ‘angina pectoris’. Angina can occur in men and women of any age, but it is more common in middle aged and elderly. This condition affects the blood flow to the heart muscles.Angina pectoris is a clinical syndrome of precordial discomfort or pressure due to transient myocardial ischemia without infarction. It is typically precipitated by exertion or psychologic stress and relieved by rest or sublingual nitroglycerin. Diagnosis is by symptoms, electrocardiography, and myocardial imaging. Treatment may include antiplatelet drugs, nitrates, beta-blockers, calcium channel blockers, angiotensin-converting enzyme inhibitors, statins, and coronary angioplasty or coronary artery bypass graft surgery. Angina pectoris occurs when
Such imbalance between supply and demand can occur when the arteries are narrowed. Narrowing usually results from Narrowing of the coronary arteries can also result from
Because myocardial oxygen demand is determined mainly by heart rate, systolic wall tension, and contractility, narrowing of a coronary artery typically results in angina that occurs during exertion and is relieved by rest. In addition to exertion, cardiac workload can be increased by disorders such as hypertension
Hypertension Hypertension is sustained elevation of resting systolic blood pressure (≥ 130 mm Hg), diastolic blood pressure (≥ 80 mm Hg), or both. Hypertension with no known cause (primary; formerly, essential... read more
A decreased oxygen supply, as in severe anemia or hypoxia, can precipitate or aggravate angina. Angina may be
In stable angina, the relationship between workload or demand and ischemia is usually relatively predictable. Atherosclerotic arterial narrowing is not entirely fixed; it varies with the normal fluctuations in arterial tone that occur in all people. Thus, more people have angina in the morning, when arterial tone is relatively high. Also, abnormal endothelial function may contribute to variations in arterial tone; eg, in endothelium damaged by atheromas, stress of a catecholamine surge causes vasoconstriction rather than dilation (normal response). As the myocardium becomes ischemic, coronary sinus blood pH falls, cellular potassium is lost, lactate accumulates, ECG abnormalities appear, and ventricular function (both systolic and diastolic) deteriorates. Left ventricular (LV) diastolic pressure usually increases during angina, sometimes inducing pulmonary congestion and dyspnea. The exact mechanism by which ischemia causes discomfort is unclear but may involve nerve stimulation by hypoxic metabolites. Symptoms and Signs of Angina Pectoris
Angina may be a vague, barely troublesome ache or may rapidly become a severe, intense precordial crushing sensation. It is rarely described as "pain." Discomfort is most commonly felt beneath the sternum, although location varies. Discomfort may radiate to the left shoulder and down the inside of the left arm, even to the fingers; straight through to the back; into the throat, jaws, and teeth; and, occasionally, down the inside of the right arm. It may also be felt in the upper abdomen. The discomfort of angina is never above the ears or below the umbilicus. Women are more likely to have atypical symptoms such as burning or tenderness in the back, shoulders, arms, or jaw. Atypical angina (eg, with bloating, gas, abdominal distress) may occur in some patients. These patients often ascribe symptoms to indigestion; belching may even relieve the symptoms. Other patients have dyspnea due to the sharp, reversible increase in LV filling pressure that often accompanies ischemia. Frequently, the patient’s description is imprecise, and whether the problem is angina, dyspnea, or both may be difficult to determine. Because ischemic symptoms require a minute or more to resolve, brief, fleeting sensations rarely represent angina. Between and even during attacks of angina, physical findings may be normal. However, during the attack, heart rate may increase modestly, blood pressure (BP) is often elevated, heart sounds become more distant, and the apical impulse is more diffuse. The 2nd heart sound (S2) may become paradoxical because LV ejection is more prolonged during an ischemic attack. A 4th heart sound (S4) is common, and a 3rd heart sound (S3) may develop. A mid or late systolic apical murmur, shrill or blowing—but not especially loud—may occur if ischemia causes localized papillary muscle dysfunction, causing mitral regurgitation. Angina pectoris is typically triggered by exertion or strong emotion, usually persists no more than a few
minutes, and subsides with rest. Response to exertion is usually predictable, but in some patients, exercise that is tolerated one day may precipitate angina the next because of variations in arterial tone. Symptoms are exaggerated when exertion follows a meal or occurs in cold weather; walking into the wind or first contact with cold air after leaving a warm room may precipitate an attack. Symptom severity is often classified by the degree of exertion resulting in angina (see table
Canadian Cardiovascular Classification System for Angina Pectoris
Canadian Cardiovascular Society Classification System for Angina Pectoris Canadian Cardiovascular Society Classification System for Angina Pectoris
Attacks may vary from several a day to symptom-free intervals of weeks, months, or years. Attacks may increase in frequency (called crescendo angina), leading to an MI or death. Conversely, attacks may gradually decrease or disappear if adequate collateral coronary circulation develops, the ischemic area infarcts, or heart failure or intermittent claudication supervenes and limits activity. Nocturnal angina may occur if a dream causes striking changes in respiration, pulse rate, and BP. Nocturnal angina may also be a sign of recurrent LV failure, an equivalent of nocturnal dyspnea. The recumbent position increases venous return, stretching the myocardium and increasing wall stress, which increases oxygen demand. Angina decubitus is angina that occurs spontaneously during rest. It is usually accompanied by a modestly increased heart rate and a sometimes markedly higher BP, which increase oxygen demand. These increases may be the cause of rest angina or the result of ischemia induced by plaque rupture and thrombus formation. If angina is not relieved, unmet myocardial oxygen demand increases further, making MI more likely. Unstable anginaSilent ischemia
Chest
discomfort Chest Pain Chest pain is a very common complaint. Many patients are well aware that it is a warning of potential life-threatening disorders and seek evaluation for minimal symptoms. Other patients, including... read more may
also be caused by gastrointestinal disorders (eg, gastroesophageal reflux
Gastroesophageal Reflux Disease (GERD) Incompetence of the lower esophageal sphincter allows reflux of gastric contents into the esophagus, causing burning pain. Prolonged reflux may lead to esophagitis, stricture, and rarely metaplasia... read more
ECG is always done. More specific tests include stress testing with ECG or with myocardial imaging (eg, echocardiography, radionuclide imaging, PET, MRI) and coronary angiography. Noninvasive tests are considered first. If done during an angina attack, ECG is likely to show reversible ischemic changes:
Between angina attacks, the ECG (and usually LV function) at rest is normal in about 30% of patients with a typical history of angina pectoris, even those with extensive 3-vessel disease. In the remaining 70%, the ECG shows evidence of previous infarction, hypertrophy, or nonspecific ST-segment and T-wave (ST-T) abnormalities. An abnormal resting ECG alone does not establish or refute the diagnosis.
If the clinical or working diagnosis is unstable angina, early stress testing is contraindicated. Exercise stress testing with ECG is done if a patient has a normal resting ECG and can exercise. In men with chest discomfort suggesting angina, stress ECG testing has a specificity of 70%; sensitivity is 90%. Sensitivity is similar in women, but specificity is lower, particularly in women < 55 (< 70%). However, women are more likely than men to have an abnormal resting ECG when CAD is present (32% vs 23%). Although sensitivity is reasonably high, exercise ECG can miss severe CAD (even left main or 3-vessel disease). In patients with atypical symptoms, a negative stress ECG usually rules out angina pectoris and CAD; a positive result may or may not represent coronary ischemia and indicates need for further testing. Stress testing with myocardial imaging is done when the resting ECG is abnormal because false-positive ST-segment shifts are common on the stress ECG. Exercise or pharmacologic stress (eg, with dobutamine or dipyridamole infusion) may be used. Imaging options include stress echocardiography, myocardial perfusion imaging with single-photon emission CT (SPECT) or PET, and stress MRI. The choice of imaging technique depends on institutional availability and expertise. Imaging tests can help assess LV function and response to stress; identify areas of ischemia, infarction, and viable tissue; and determine the site and extent of myocardium at risk. Stress echocardiography can also detect ischemia-induced mitral regurgitation. Coronary
angiography Angiography Cardiac catheterization is the passage of a catheter through peripheral arteries or veins into cardiac chambers, the pulmonary artery, and coronary arteries and veins. Cardiac catheterization... read more
Intravascular ultrasonography provides images of coronary artery structure. An ultrasound probe on the tip of a catheter is inserted in the coronary arteries during angiography. This test can provide more information about coronary anatomy than other tests; it is indicated when the nature of lesions is unclear or when apparent disease severity does not match symptom severity. Used with angioplasty, it can help ensure optimal placement of stents. Guidewires with pressure or flow sensors can be used to estimate blood flow across stenoses. Blood flow is expressed as fractional flow reserve (FFR), which is the ratio of maximal flow through the stenotic area to normal maximal flow. These flow measurements are most useful when evaluating the need for angioplasty or CABG in patients with lesions of questionable severity (40 to 70% stenosis). An FFR of 1.0 is considered normal, while an FFR < 0.75 to 0.8 is associated with myocardial ischemia. Lesions with an FFR > 0.8 are less likely to benefit from stent placement. Imaging studies done at rest can evaluate the coronary arteries. Electron beam CT can detect the amount of calcium present in coronary artery plaque. The calcium score is roughly proportional to the risk of subsequent coronary events. However, because calcium may be present in the absence of significant stenosis, the score does not correlate well with the need for angioplasty or CABG. Thus, the American Heart Association recommends that screening with electron beam CT should be done only for select groups of patients and is most valuable when combined with historical and clinical data to estimate risk of death or nonfatal myocardial infarction (1 Diagnosis references Angina pectoris is a clinical syndrome of precordial discomfort or pressure due to transient myocardial ischemia without infarction. It is typically precipitated by exertion or psychologic stress... read more ). These groups may include asymptomatic patients with an intermediate 10-year atherosclerotic cardiovascular disease (ASCVD) risk estimate (10 to 20%) and symptomatic patients with equivocal stress test results. Electron beam CT is particularly useful in ruling out significant CAD in patients presenting to the emergency department with atypical symptoms, normal troponin levels, and a low probability of hemodynamically significant coronary artery disease. These patients may have noninvasive testing as outpatients. Multidetector row CT (MDRCT) coronary angiography can accurately identify coronary stenosis and has a number of advantages. The test is noninvasive, can exclude coronary stenosis with high accuracy, can establish stent or bypass graft patency, can show cardiac and coronary venous anatomy, and can assess calcified and noncalcified plaque burden. Estimation of the fractional flow reserve (FFR) across significant lesions and estimation of lesion-specific ischemia are also possible (2 Diagnosis references Angina pectoris is a clinical syndrome of precordial discomfort or pressure due to transient myocardial ischemia without infarction. It is typically precipitated by exertion or psychologic stress... read more ). However, radiation exposure is significant, and the test is not suitable for patients with a heart rate of > 65 beats/minute, those with irregular heart beats, and pregnant women. Patients must also be able to hold their breath for 15 to 20 seconds, 3 to 4 times during the study. Evolving indications for MDRCT coronary angiography include
Cardiac MRI is invaluable in evaluating many cardiac and great vessel abnormalities. It may be used to evaluate CAD by several techniques, which enable direct visualization of coronary stenosis, assessment of flow in the coronary arteries, evaluation of myocardial perfusion and metabolism, evaluation of wall motion abnormalities during stress, and assessment of infarcted myocardium vs viable myocardium. Indications for cardiac MRI include evaluation of cardiac structure and function and assessment of myocardial viability. Cardiac MRI, specifically stress perfusion MRI and quantitative myocardial blood flow analysis, may also be indicated for diagnosis and risk assessment in patients with either known or suspected CAD.
The main adverse outcomes of angina pectoris are
unstable angina
Unstable Angina Unstable angina results from acute obstruction of a coronary artery without myocardial infarction. Symptoms include chest discomfort with or without dyspnea, nausea, and diaphoresis. Diagnosis... read more ,
myocardial infarction
Acute Myocardial Infarction (MI) Acute myocardial infarction is myocardial necrosis resulting from acute obstruction of a coronary artery. Symptoms include chest discomfort with or without dyspnea, nausea, and/or diaphoresis... read more
Prognosis worsens with increasing age, increasingly severe anginal symptoms, presence of anatomic lesions, and poor ventricular function. Lesions in the left main coronary artery or proximal left anterior descending artery indicate particularly high risk. Although prognosis correlates with number and severity of coronary arteries affected, prognosis is surprisingly good for patients with stable angina, even those with 3-vessel disease, if ventricular function is normal.
Reversible risk
factors are modified Treatment Atherosclerosis is characterized by patchy intimal plaques (atheromas) that encroach on the lumen of medium-sized and large arteries. The plaques contain lipids, inflammatory cells, smooth muscle... read more
The main goals of angina treatment are to
To relieve symptoms during an acute attack, sublingual nitroglycerin is the most effective drug. Nitroglycerin is a potent smooth-muscle relaxant and vasodilator. Its main sites of action are in the peripheral vascular tree, especially in the venous or capacitance system, and in coronary blood vessels. Even severely atherosclerotic vessels may dilate in areas without atheroma. Nitroglycerin lowers systolic BP and dilates systemic veins, thus reducing myocardial wall tension, a major determinant of myocardial oxygen need. Sublingual nitroglycerin is given for an acute attack or for prevention before exertion. Dramatic relief usually occurs within 1.5 to 3 minutes, is complete by about 5 minutes, and lasts up to 30 minutes. The dose may be repeated every 4 to 5 minutes up to 3 times if relief is incomplete. Patients should always carry nitroglycerin tablets or aerosol spray to use promptly at the onset of an angina attack. Patients should store tablets in a tightly sealed, light-resistant glass container, so that potency is not lost. Because the drug deteriorates quickly, small amounts should be obtained frequently. To prevent ischemia, several classes of drugs are used:
Antiplatelet drugs inhibit platelet aggregation. Aspirin binds irreversibly to platelets and inhibits cyclooxygenase and platelet aggregation. Other antiplatelet drugs (eg, clopidogrel, prasugrel, and ticagrelor) block adenosine diphosphate–induced platelet aggregation. These drugs can reduce risk of ischemic events (MI, sudden death), but the drugs are most effective when given with aspirin. Patients unable to tolerate one should receive the other drug alone. Beta-blockers limit symptoms and prevent infarction and sudden death better than other drugs. Beta-blockers block sympathetic stimulation of the heart and reduce systolic BP, heart rate, contractility, and cardiac output, thus decreasing myocardial oxygen demand and increasing exercise tolerance. Beta-blockers also increase the threshold for ventricular fibrillation. Most patients tolerate these drugs well. Many beta-blockers are available and effective. Dose is titrated upward as needed until limited by bradycardia or adverse effects. Patients who cannot tolerate beta-blockers are given a calcium channel blocker with negative chronotropic effects (eg, diltiazem, verapamil). Those at risk of beta-blocker intolerance (eg, those with asthma) may be tried on a cardioselective beta-blocker (eg, bisoprolol) perhaps with pulmonary function testing before and after drug administration to detect drug-induced bronchospasm. Long-acting nitrates (oral or transdermal) are used if symptoms persist after the beta-blocker dose is maximized. If angina occurs at predictable times, a nitrate is given to cover those times. Oral nitrates include isosorbide dinitrate and mononitrate (the active metabolite of the dinitrate). They are effective within 1 to 2 hours; their effect lasts 4 to 6 hours. Sustained-release formulations of isosorbide mononitrate appear to be effective throughout the day. For transdermal use, cutaneous nitroglycerin patches have largely replaced nitroglycerin ointments primarily because ointments are inconvenient and messy. Patches slowly release the drug for a prolonged effect; exercise capacity improves 4 hours after patch application and wanes in 18 to 24 hours. Nitrate tolerance may occur, especially when plasma concentrations are kept constant. Because risk of myocardial infarction is highest in early morning, an afternoon or early evening respite period from nitrates is reasonable unless a patient commonly has angina at that time. For nitroglycerin, an 8- to 10-hour respite period seems sufficient. Isosorbide may require a 12-hour respite period. If given once a day, sustained-release isosorbide mononitrate does not appear to elicit tolerance. Ranolazine is a sodium channel blocker that can be used to treat chronic angina. Because ranolazine may also prolong QTc, it is usually reserved for patients in whom symptoms persist despite optimal treatment with other antianginal drugs. Dizziness, headache, constipation, and nausea are the most common adverse effects. Ivabradine is a sinus node inhibitor that inhibits inward sodium/potassium current in a certain gated channel (funny or "f" channel) in sinus node cells, thus slowing heart rate without decreasing contractility. It can be used for symptomatic treatment of chronic stable angina pectoris in patients with normal sinus rhythm who cannot take beta-blockers or in combination with beta-blockers in patients inadequately controlled by beta-blocker alone and whose heart rate is > 60 beats/minute
Revascularization
Revascularization for Acute Coronary Syndromes Revascularization is the restoration of blood supply to ischemic myocardium in an effort to limit ongoing damage, reduce ventricular irritability, and improve short-term and long-term outcomes... read more , either with
PCI
Percutaneous Coronary Interventions (PCI) Percutaneous coronary interventions (PCI) include percutaneous transluminal coronary angioplasty (PTCA) with or without stent insertion. Primary indications are treatment of Angina pectoris... read more
PCI is usually preferred for 1- or 2-vessel disease with suitable anatomic lesions and is increasingly being used for 3-vessel disease. Lesions that are long or near bifurcation points are often not amenable to PCI. However, as stent technology improves, PCI is being used for more complicated cases. CABG is very effective in selected patients with angina. CABG is superior to PCI in patients with diabetes and in patients with multivessel disease amenable to grafting. The ideal candidate has severe angina pectoris and localized disease, or diabetes mellitus. About 85% of patients have complete or dramatic symptom relief. Exercise stress testing shows positive correlation between graft patency and improved exercise tolerance, but exercise tolerance sometimes remains improved despite graft closure. CABG improves survival for patients with left main disease, those with 3-vessel disease and poor left ventricular function, and some patients with 2-vessel disease. However, for patients with mild or moderate angina (CCS class 1 or 2) or 3-vessel disease and good ventricular function, CABG appears to only marginally improve survival. PCI is increasingly being used for unprotected left main stenosis (ie, no left anterior descending or circumflex graft present), with outcomes at one year that are similar to CABG. Several studies show better long term outcomes following CABG than with PCI for patients with diabetes and proximal left anterior descending disease. For patients with 1-vessel disease, outcomes with drug therapy, PCI, and CABG are similar; exceptions are left main disease and proximal left anterior descending disease, for which revascularization appears advantageous.
Where is the pain in myocardial infarction?Chest pain is the most common presenting complaint of acute myocardial infarction. The classic manifestation of ischemia is usually described as a heavy chest pressure or squeezing, a “burning” feeling, or difficulty in breathing. The discomfort or pain often radiates to the left shoulder, neck, or arm.
How does myocardial infarction cause pain?The chest pain caused by a heart attack is a direct result of the heart muscle cells not receiving enough blood. This is similar in mechanism to when not getting enough oxygen to your skeletal muscles while exercising can cause them to cramp or spasm.
Is death by myocardial infarction painful?During a heart attack, a person may feel pain in the middle of the chest that can spread to the back, jaw or arms. The pain may also be felt in all of these places and not the chest. Sometime the pain is felt in the stomach area, where it may be taken for indigestion.
Which of the following is the most common symptom of myocardial infarction?Common heart attack symptoms include: Chest pain that may feel like pressure, tightness, pain, squeezing or aching.
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