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ATI Comprehensive Predictor 2023 Exit Exam A
ATI Comprehensive Predictor 2023 Exit Exam A ( 176 Questions)
A nurse is providing care for a client who experienced a myocardial infarction prior to a cardiac arrest. Which of the following laboratory tests will identify early injury to the cardiac muscle?
Creatine kinase (CK) test: While creatine kinase isoenzymes, including CK-MB, can be elevated following myocardial infarction (MI), they are not specific to cardiac muscle injury. CK is found in various tissues throughout the body, so elevated levels can also indicate damage to skeletal muscle or brain tissue, among other sources.
Creatine kinase-myocardial band (CK-MB) test: CK-MB is a cardiac-specific isoform of creatine kinase, and elevated levels can indicate myocardial injury, particularly in the context of an acute MI. However, troponin T is a more sensitive and specific marker for myocardial injury.
Brain natriuretic peptide (BNP) test: Brain natriuretic peptide is primarily used in the diagnosis and management of heart failure. While elevated BNP levels can indicate heart muscle strain or stress, they are not specific markers for acute myocardial infarction or early injury to the cardiac muscle.
Troponin T test: This is the correct answer. Troponin T is a highly specific marker for cardiac muscle injury. Elevated troponin levels can be detected within hours of myocardial infarction and persist for several days, making it an essential tool in the diagnosis of acute coronary syndromes, including myocardial infarction. Troponin T is considered one of the gold standard biomarkers for detecting early injury to the cardiac muscle.
Answer: D. Troponin T test
Rationale:
A. Creatine kinase (CK) test: While creatine kinase isoenzymes, including CK-MB, can be elevated following myocardial infarction (MI), they are not specific to cardiac muscle injury. CK is found in various tissues throughout the body, so elevated levels can also indicate damage to skeletal muscle or brain tissue, among other sources.
B. Creatine kinase-myocardial band (CK-MB) test: CK-MB is a cardiac-specific isoform of creatine kinase, and elevated levels can indicate myocardial injury, particularly in the context of an acute MI. However, troponin T is a more sensitive and specific marker for myocardial injury.
C. Brain natriuretic peptide (BNP) test: Brain natriuretic peptide is primarily used in the diagnosis and management of heart failure. While elevated BNP levels can indicate heart muscle strain or stress, they are not specific markers for acute myocardial infarction or early injury to the cardiac muscle.
D. Troponin T test: This is the correct answer. Troponin T is a highly specific marker for cardiac muscle injury. Elevated troponin levels can be detected within hours of myocardial infarction and persist for several days, making it an essential tool in the diagnosis of acute coronary syndromes, including myocardial infarction. Troponin T is considered one of the gold standard biomarkers for detecting early injury to the cardiac muscle.