Coronary ischemia: Difference between revisions
m v2.03b - Bot T20 CW#61 - WP:WCW project (Reference before punctuation) |
Added a new section on stress echocardiography to complement section on stress electrocardiogram |
||
| Line 35: | Line 35: | ||
A [[treadmill]] or [[exercise bike]] will be used. The incline or resistance of the bike are steadily increased until the target heart rate for the person's age and weight is reached.<ref name="DCH" /> However, an exercise stress test is not always accurate in determining the presence of a blockage in the arteries. Women and those who are young may show abnormalities on their test even though no signs of coronary ischemia or CAD are present.<ref name="DCH" /> |
A [[treadmill]] or [[exercise bike]] will be used. The incline or resistance of the bike are steadily increased until the target heart rate for the person's age and weight is reached.<ref name="DCH" /> However, an exercise stress test is not always accurate in determining the presence of a blockage in the arteries. Women and those who are young may show abnormalities on their test even though no signs of coronary ischemia or CAD are present.<ref name="DCH" /> |
||
=== Stress Echocardiography === |
|||
Stress echocardiography is very commonly used in assessing for ischemia resulting from coronary artery disease. It can be performed exercising, preferably with a bicycle that allows the patient to exercise while lying flat, which allows for imaging throughout the entire testing period<ref>{{Cite journal|last=Banerjee|first=A.|last2=Newman|first2=D. R.|last3=Van den Bruel|first3=A.|last4=Heneghan|first4=C.|date=2012-05|title=Diagnostic accuracy of exercise stress testing for coronary artery disease: a systematic review and meta-analysis of prospective studies|url=https://pubmed.ncbi.nlm.nih.gov/22512607|journal=International Journal of Clinical Practice|volume=66|issue=5|pages=477–492|doi=10.1111/j.1742-1241.2012.02900.x|issn=1742-1241|pmid=22512607}}</ref>. While the patient is exercising, images of the of the heart in motion are generated<ref name=":0">{{Cite journal|last=Gurunathan|first=Sothinathan|last2=Senior|first2=Roxy|date=10 18, 2017|title=Stress Echocardiography in Stable Coronary Artery Disease|url=https://pubmed.ncbi.nlm.nih.gov/29046974|journal=Current Cardiology Reports|volume=19|issue=12|pages=121|doi=10.1007/s11886-017-0935-x|issn=1534-3170|pmid=29046974}}</ref>. Ischemia can be detected by visualizing abnormalities in the movement of the heart and the thickness of the heart wall during exercise<ref name=":0" />. |
|||
Some people may be unable to exercise in order to achieve a sufficient heart rate for a useful test. In these cases, high-dose dobutamine may be used to chemically increase heart rate<ref name=":1">{{Cite journal|last=Mordi|first=Ify R.|last2=Badar|first2=Athar A.|last3=Irving|first3=R. John|last4=Weir-McCall|first4=Jonathan R.|last5=Houston|first5=J. Graeme|last6=Lang|first6=Chim C.|date=2017|title=Efficacy of noninvasive cardiac imaging tests in diagnosis and management of stable coronary artery disease|url=https://pubmed.ncbi.nlm.nih.gov/29200864|journal=Vascular Health and Risk Management|volume=13|pages=427–437|doi=10.2147/VHRM.S106838|issn=1178-2048|pmc=5701553|pmid=29200864}}</ref>. If dobutamine is insufficient for this purpose, atropine be added to reach goal heart rate<ref name=":1" />. Dipyridamole is an alternative to dobutamine but it is less effective in detecting abnormalities<ref name=":0" />. While exercise echocardiograms are more effective in detecting coronary artery disease, all forms of stress echocardiograms are more effective than exercise EKG in detecting coronary ischemia secondary to coronary artery disease<ref name=":1" />. If stress echocardiography is normal, risk of future adverse cardiac events is low enough that invasive coronary angiography is not needed<ref name=":0" />. |
|||
===Coronary angiography=== |
===Coronary angiography=== |
||
Revision as of 16:19, 24 November 2020
Coronary ischemia, myocardial ischemia,[1] or cardiac ischemia,[2] is a medical term for a reduced blood flow in the coronary circulation through the coronary arteries.[3] Coronary ischemia is linked to heart disease, and heart attacks.
Symptoms and signs
Symptoms of coronary ischemia can last for a short time, or for a longer time which may suggest a heart attack.[2] The main symptom is chest pain. Symptoms of coronary ischemia can be classified as typical or atypical.[2]
Typical
Chest pain is a major indication of coronary ischemia. If chest pain occurs while exercising, or during sex, but it doesn't persist after rest, it may be coronary ischemia, or what is called, angina.[2] Some people characterize the pain they feel as though an elephant is sitting on their chest. Other typical symptoms include perspiration including sweaty palms, and clammy skin, nausea or vomiting, or shortness of breath.[2] Chest pain radiating down the left arm is also a symptom, and the pain can radiate directly to the back in some instances.
Atypical
Most atypical symptoms are seen in women, diabetics, and the elderly more than anyone else.[2] These type of symptoms include stomach pain, and simply fatigue. It can also include heartburn and anxiety.[2] If no symptoms are present it is called silent ischemia.[4]
Consequences
Coronary ischemia has some serious consequences if it is not treated. It can cause high blood pressure, and high cholesterol if not treated, which can lead to a heart attack or stroke.[5] There may be temporary chest pain or angina. A heart attack can cause arrythmias, as well as permanent damage to the heart muscle.[5]
Causes
Coronary artery disease (CAD) occurs when fatty substances adhere to the walls of coronary arteries supplying the heart, narrowing them and constricting blood flow, a process known as atherosclerosis, the most common cause of coronary ischemia.[5] Lack of oxygen may also result in a myocardial infarction (heart attack).[6]
CAD can be contracted over time. Risk factors include a family history of CAD, smoking, high blood pressure, diabetes, obesity, inactive lifestyle and high cholesterol.[6]
Diagnosis
If coronary ischemia is suspected, a series of tests will be undertaken for confirmation. The most common tests used are an electrocardiogram, an exercise stress test, and a coronary angiography.[7] A medical history will be taken, including queries about past incidences of chest pain or shortness of breath. The duration and frequency of symptoms will be noted as will any measures taken to relieve the symptoms.[7]
Electrocardiogram
An electrocardiogram (ECG) involves the use of electrodes that are placed on the arms, chest, and legs.[7] These sensors detect any abnormal rhythms that the heart may be producing. This test is painless and it helps detect insufficient blood flow to the heart.[7] An ECG can also detect any damage that has been done in the past to the heart. This test can also detect any thickening in the walls of the left ventricles as well as any defects in the electrical impulses of the heart.[7] It is quick and provides the Physician with the P/PR, Heart Rate, QRS, QT/QTcF, P/QRS/T, and axis results.
Exercise stress test
A cardiac stress test, puts stress on the heart through exercise. A series of exercises to measure the tolerance for stress on the heart will be carried out. This test uses an ECG to detect the electrical impulses of the heart during physical exertion.[7]
A treadmill or exercise bike will be used. The incline or resistance of the bike are steadily increased until the target heart rate for the person's age and weight is reached.[7] However, an exercise stress test is not always accurate in determining the presence of a blockage in the arteries. Women and those who are young may show abnormalities on their test even though no signs of coronary ischemia or CAD are present.[7]
Stress Echocardiography
Stress echocardiography is very commonly used in assessing for ischemia resulting from coronary artery disease. It can be performed exercising, preferably with a bicycle that allows the patient to exercise while lying flat, which allows for imaging throughout the entire testing period[8]. While the patient is exercising, images of the of the heart in motion are generated[9]. Ischemia can be detected by visualizing abnormalities in the movement of the heart and the thickness of the heart wall during exercise[9].
Some people may be unable to exercise in order to achieve a sufficient heart rate for a useful test. In these cases, high-dose dobutamine may be used to chemically increase heart rate[10]. If dobutamine is insufficient for this purpose, atropine be added to reach goal heart rate[10]. Dipyridamole is an alternative to dobutamine but it is less effective in detecting abnormalities[9]. While exercise echocardiograms are more effective in detecting coronary artery disease, all forms of stress echocardiograms are more effective than exercise EKG in detecting coronary ischemia secondary to coronary artery disease[10]. If stress echocardiography is normal, risk of future adverse cardiac events is low enough that invasive coronary angiography is not needed[9].
Coronary angiography
A coronary angiography is performed only after a stress test or ECG shows a sign of coronary ischemia or CAD. This test is very important in finding where the blockages are in the arteries.[7] This test helps determine if an angioplasty or bypass surgery is needed.
During this test the doctor makes a small incision in the patient's groin (femoral) or wrist (radial) and inserts a catheter. The catheter has a very small video camera on the end of it so that the doctor can find the arteries.[7] Once he has found the arteries, he injects a dye in them so that he/she can detect any blockages in the arteries. The dye is able to be seen on a special x-ray machine.[7] The test takes one to two hours.
Treatment
 |
Coronary ischemia can be treated but not cured.[11] By changing lifestyle, further blockages can be prevented. A change in lifestyle, mixed with prescribed medication, can improve health.
Not smoking
A study showed that those who quit smoking reduced their risk of being hospitalized over the next two years.[11] Smoking increases blood pressure, as well as increases the risk of high cholesterol. Quitting can lower blood pressure, and triglyceride levels. Secondhand smoke is also bad for the heart health.[11]
Healthy diet
A healthy diet is a very important factor in preventing coronary ischemia or coronary artery disease.[11] A heart healthy diet is low in saturated fat and cholesterol and high in complex carbohydrates.[11] Complex carbohydrates include fruits, vegetables, and whole grains. These food choices can reduce the risk of a heart attack or any other congestive heart failure event.[11] A heart healthy diet also includes low sodium intake and a higher potassium intake.[11] A low potassium intake raises blood pressure, as does a diet high in sodium.
Physical activity
By increasing physical activity, it is possible to manage body weight, reduce blood pressure, and relieve stress.[11] The Center for Disease Control recommends 30 minutes of physical activity a day.[11] Instead of 30 minutes a day at one time, short bursts of physical activity for 8–10 minutes three times a day are also suitable. Exercising this way can reduce the risk of getting heart disease or coronary ischemia, if it is performed at moderate intensity.[11]
References
- ^ "Myocardial ischemia". Mayo Clinic. Retrieved 2019-11-29.
- ^ a b c d e f g Potochny, Evy. "Cardiac Ischemia Symptoms." LiveStrong. Demand Media, 9 March 2010. Web. 6 Nov. 2010.
- ^ "Sacred Heart Medical Center. Spokane, Washington. Coronary Ischemia". Shmc.org. Retrieved 2008-12-28.
- ^ "Silent Ischemia and Ischemic Heart Disease". www.heart.org.
- ^ a b c ["Ischemia." Ischemic Heart Disease. Ischemic Heart Disease, n.d. Web. 6 Nov. 2010.]
- ^ a b [RelayHealth. "Coronary Artery Disease." Adult Health Advisor (July 2009): 1. Consumer Health Complete. Web. 4 Nov. 2010.]
- ^ a b c d e f g h i j k [Gerstenblith, Gary, and Simeon. Margolis. "Diagnosis of Coronary Heart Disease." Hopkins Heart (Jan. 2008): 18-25. Consumer Health Complete. Web. 17 Nov. 2010.]
- ^ Banerjee, A.; Newman, D. R.; Van den Bruel, A.; Heneghan, C. (2012-05). "Diagnostic accuracy of exercise stress testing for coronary artery disease: a systematic review and meta-analysis of prospective studies". International Journal of Clinical Practice. 66 (5): 477–492. doi:10.1111/j.1742-1241.2012.02900.x. ISSN 1742-1241. PMID 22512607.
{{cite journal}}: Check date values in:|date=(help) - ^ a b c d Gurunathan, Sothinathan; Senior, Roxy (10 18, 2017). "Stress Echocardiography in Stable Coronary Artery Disease". Current Cardiology Reports. 19 (12): 121. doi:10.1007/s11886-017-0935-x. ISSN 1534-3170. PMID 29046974.
{{cite journal}}: Check date values in:|date=(help) - ^ a b c Mordi, Ify R.; Badar, Athar A.; Irving, R. John; Weir-McCall, Jonathan R.; Houston, J. Graeme; Lang, Chim C. (2017). "Efficacy of noninvasive cardiac imaging tests in diagnosis and management of stable coronary artery disease". Vascular Health and Risk Management. 13: 427–437. doi:10.2147/VHRM.S106838. ISSN 1178-2048. PMC 5701553. PMID 29200864.
{{cite journal}}: CS1 maint: unflagged free DOI (link) - ^ a b c d e f g h i j [Gerstenblith, Gary, and Simeon Margolis. "Lifestyle Measures to Prevent and Treat Coronary Artery Disease." Hopkins Heart (Jan. 2008): 25-36. Consumer Health Complete. Web. 29 Nov. 2010.]