Inferior wall myocardial infarction stems from ischemia and necrosis due to occlusion of the right coronary and/or distal circumflex arteries that supply this area of the heart. The clinical presentation most commonly encompasses chest pain that often spreads to other parts of the body (the extremities, the back, or the head and neck), whereas an array of additional symptoms can be present - nausea, vomiting, diaphoresis, palpitations, weakness, etc. The diagnosis rests on a prompt clinical assessment followed by a laboratory investigation with electrocardiography.
The clinical presentation of an inferior wall myocardial infarction is no different from other types of infarctions. Occlusion of the arterial vessel (the right coronary and the distal circumflex arteries supply the inferior myocardial wall) leads to ischemia and subsequent necrosis of local tissue, resulting in the appearance of signs . Chest pain is widely described as the predominant finding in the setting of a myocardial infarction and is present in virtually all patients   . The pain (generally located retrosternally or precordially) is reported as "burning" or as a heavy "squeezing" pressure on the chest, lasting > 20 minutes in more than 90% of cases . An important feature of chest pain seen in myocardial infarction is its frequent radiation to other parts of the body - the head and neck area (particularly the jaw), the shoulders, arms and forearms; and the back and interscapular region, either in a unilateral or less commonly bilateral fashion  . The pain may significantly range in terms of severity- some report only mild discomfort, whereas others complain of excruciating pain  . Important additional symptoms are vomiting, nausea, weakness, fatigue, shortness of breath, excessive sweating, abdominal pain, or even palpitations  .
- Chest Pain
ST segment elevation in the right precordial leads was short lived, having disappeared within 10 hours after the onset of chest pain in half of our patients with right ventricular involvement. [ncbi.nlm.nih.gov]
Chest pain is widely described as the predominant finding in the setting of a myocardial infarction and is present in virtually all patients. [symptoma.com]
- Heart Disease
Smoking and diabetes were more prevalent in RVMI group, while hypertension and family history of ischemic heart disease were more common in isolated IWMI. Ninety per cent of patients received thrombolytic therapy. [ncbi.nlm.nih.gov]
Ischemic heart diseases Use Additional code to identify presence of hypertension ( I10-I16 ) Ischemic heart diseases I21 ICD-10-CM Diagnosis Code I21 Acute myocardial infarction 2016 2017 2018 - Revised Code 2019 Non-Billable/Non-Specific Code Includes [icd10data.com]
National Heart Attack Alert Program: How is a Heart Attack Treated? Available online at http://www.nhlbi.nih.gov/health/dci/Diseases/HeartAttack/HeartAttack_Treatments.html. Accessed September 2008. [labtestsonline.it]
Usually there is no history of angina or heart attack, and risk factors for ischemic heart disease may not be present [ 2 ]. This is a case of a 59-year old woman with acute ST-elevated myocardial infarction (STEMI) with normal coronary arteries. 2. [pubs.sciepub.com]
- Retrosternal Chest Pain
A 56-years old female comes with acute onset retrosternal chest pain of 6 hours duration along with palpitation, sweating, giddiness and dyspnoea. She was a known case of diabetes mellitus and hypertension since last 10 years. [praveenkumargupta2002.blogspot.com]
Myocardial infarction is a medical emergency and a prompt diagnosis is potentially life-saving. Through a detailed patient history and a comprehensive clinical examination, the physician plays a key role in raising initial suspicion. The onset of signs, as well as their progression and severity, should be assessed during the initial encounter with the patient. To make a solid diagnosis, however, two important steps of the workup should be covered - cardiac markers and electrocardiography     . The calcium-dependent troponins are currently regarded as the most specific test used to identify myocardial changes    . Troponins T and I are cardiac-specific markers that are pathologically elevated about 6 hours after myocardial ischemia ensued, while their peak values are seen about 24 hours after the event . Creatine kinase myocardial band (CK-MB), on the other hand, was until recently included in the biochemical panel, but its very low accuracy and value to physicians have led to its elimination from the workup of these individuals . On electrocardiography, inferior myocardial infarction exhibits pathological changes in limb leads II, III, and aVF, in the form of ST elevation or depression, and/or T wave inversion in 2 contiguous leads as diagnostic criteria   . Coronary angiography can be further used to assess the severity of the infarction .
- Inferior Q Wave
Bundle branch block during acute Q wave inferior wall myocardial infarction was present in 108 patients (4.9%), 85 of whom had right and 23 left bundle branch block. [ncbi.nlm.nih.gov]
Q waves - not Old Inferior Wall Myocardial Infarction (MI) ECG Old Inferior Wall Myocardial Infarction (MI) ECG (Example 1) Old Inferior Wall Myocardial Infarction (MI) ECG (Example 2) References: 1. [healio.com]
(necrosis) (Pathologic Q waves are usually defined as duration ≥ 0.04 s or ≥ 25% of R-wave amplitude) Pathologic Q waves, T wave inversion (necrosis and fibrosis) Pathologic Q waves, upright T waves (fibrosis) Inferior MI Family (includes inferior, true [ecg.utah.edu]
- Narrow QRS Complex
Electrophysiologic study performed in one patient and a narrow QRS complex in the other patient during the alternate Wenckebach periods confirmed the atrioventricular node as the level of block. [ncbi.nlm.nih.gov]
QT, RR, ST Intervals
- ST Elevation
In left circumflex artery (LCX) occlusions, significantly more ST depression was seen in leads V1-3 (most significantly in lead V2) and ST elevation in lead II. [ncbi.nlm.nih.gov]
ST elevation (STEMI) myocardial infarction involving other coronary artery of anterior wall I21.1 ST elevation (STEMI) myocardial infarction of inferior wall I21.11 ST elevation (STEMI) myocardial infarction involving right coronary artery I21.19 ST [icd10data.com]
I21.0 ST elevation (STEMI) myocardial infarction of anterior wall Inclusion term(s): Type 1 ST elevation myocardial infarction of anterior wall I21.01 ST elevation (STEMI) myocardial infarction involving left main coronary artery I21.02 ST elevation [icd10coded.com]
In our study, ST elevation in lead III>II was seen in 91 patients (75.21%) whereas ST elevation in lead II>III was seen in 30 patients (24.79%). [omicsonline.org]
- T Wave Inversion
Diagnostic Q waves were defined as a significant Q or QS of at least 30-ms duration. Diagnostic T-wave inversion was defined as complete T inversion or biphasic waves with initial, predominantly negative deflection. [ncbi.nlm.nih.gov]
On electrocardiography, inferior myocardial infarction exhibits pathological changes in limb leads II, III, and aVF, in the form of ST elevation or depression, and/or T wave inversion in 2 contiguous leads as diagnostic criteria. [symptoma.com]
Within a few hours, you can begin to see negative T waves or T wave inversion as the MI evolves. The T wave inversion can persist for months after the MI. [dummies.com]
ST segment depression and T wave inversion 5 components of Pain Assessment P - precipitating Q - quality R - radiation S - severity T - timing 1. [quizlet.com]
[…] of fibrinolytic treatment--is often faced. [revespcardiol.org]
The average heart rate decreased from 82 +/- 11 to 69 +/- 9 beats/min (p less than 0.05) and the mean arterial blood pressure increased from 81 +/- 12 mm Hg before metaraminol treatment to 126 +/- 8 mm Hg after treatment. [ncbi.nlm.nih.gov]
CONCLUSIONS: RVI is associated with worse prognosis and increased number of in-hospital complications. Older patients aged >70 years have definitely poorer prognosis. Thrombolytic therapy in a subgroup of older patients with RVI remains ineffective. [ncbi.nlm.nih.gov]
It is well known that congestive heart failure (CHF) complicating acute MI has poor prognosis. [link.springer.com]
Right ventricular infarctions as an independent predictor of prognosis after acute inferior myocardial infarction. N Engl J Med. 1993;328:981-988. 5. Turhan H, Yilmaz MB, Yetkin E, et al. [consultant360.com]
Electrocardiographic signs of LAH in the presence of IWMI are outlined, and the behavior and etiology of the T-wave changes are analyzed. [ncbi.nlm.nih.gov]
Certain conditions have both an underlying etiology and multiple body system manifestations due to the underlying etiology. [icd10coded.com]
ETIOLOGY 7. CLINICAL FEATURES 8. DIAGNOSIS 9. TREATMENT 10. COMPLICATIONS 11. CONCLUSION 12. TAKE HOME MESSAGE THE PIONEERS HAROLD ENSIGN BENNET PARDEE EINTHOVEN PAUL DUDLEY WHITE 13. 2D ECHO 14. [slideshare.net]
[…] biomarkers of myocardial necrosis Epidemiology incidence increases with age risk factors hypertension cigarette smoking hyperlipidemia hypercholesterolemia male postmenopause genetic and behavioral predispositions to arteriosclerosis e.g., high-fat diet Etiology [medbullets.com]
EPIDEMIOLOGY-India In India, cardiovascular disease (CVD) is the leading cause of death. 32% of all deaths in 2007. Relatively new epidemic in India. [slideshare.net]
Epidemiology It is difficult to be sure of the percentage of myocardial infarctions that are posterior because it seems likely that many are missed. [ 3 ] The risk factors are the same for any cardiovascular disease, such as smoking, hypertension, diabetes [patient.info]
[…] necrosis are present Non-STEMI (NSTEMI) an ACS without ST-segment elevations found on ECG biomarkers of myocardial necrosis are present unstable angina an ACS without ST-segment elevations found on ECG and no elevation biomarkers of myocardial necrosis Epidemiology [medbullets.com]
"Epidemiology of heart failure and left ventricular systolic dysfunction after acute myocardial infarction: prevalence, clinical characteristics, and prognostic importance". [en.wikipedia.org]
These findings, together with earlier ones, may contribute to our understanding of the pathophysiology of the presence of ST-segment depression in the precordial leads in inferior wall acute MI. [ncbi.nlm.nih.gov]
[…] subsequent thrombi expansion vasospasm emboli, which can be secondary to atrial fibrillation, sending an embolus from the left atrium to the coronary arteries vegetations from infective endocarditis material from an intracardiac prosthetic paradoxical emboli Pathophysiology [medbullets.com]
Right ventricular myocardial infarction: From pathophysiology to prognosis. Exp. Clin. Cardiol., 18: 27-30. Direct Link | Rudski, L.G., W.W. Lai, J. Afilalo, L. Hua and M.D. Handschumacher et al ., 2010. [scialert.net]
Pathophysiology of Heart Disease: A Collaborative Project of Medical Students and Faculty. Lippincott Williams & Wilkins. p. 172. ISBN 9781469816685. [en.wikipedia.org]
Delay in diagnosis may also contribute. [ 7 ] Prevention See the separate Prevention of Cardiovascular Disease article. [patient.info]
"Vitamin and mineral supplements in the primary prevention of cardiovascular disease and cancer: An updated systematic evidence review for the U.S. Preventive Services Task Force". [en.wikipedia.org]
But if you do get quick treatment, you may be able to prevent or limit damage to the heart muscle. That's why it's important to know the symptoms of a heart attack and call 9-1-1 if you or someone else is having them. [icdlist.com]
For secondary prevention, beta-blocker therapy will continue after discharge because it decreases mortality after MI by 30%. [americannursetoday.com]
Through this case report, we emphasise the importance of intracoronary fibrinolysis for LMCA thrombosis to prevent the risk of distal embolisation with thrombectomy. [healthcare-bulletin.com]
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