Cardiology Flashcards
Cardiac Markers
CTNT < 22 < 14
CKMB < 10
Definition of acute myocardial infarction (MI)
- Rise and/or fall of troponin with at least one value above the upper 99% reference value and at least one of the following:
-ischemic sx, Q waves, ECG changes, imaging evidence of loss of myocardium, intracoronary thrombus - Cardiac death prior to getting biomarkers
- MI following cardiac intervention
Classification of MIs
Type 1: Spontaneous MI related to intraluminal thrombus
Type 2: MI secondary to an ischemic imbalance between myocardial oxygen supply and/or demand
Type 3: MI resulting in death when biomarker values are unavailable
Type 4a: MI related to percutaneous coronary intervention (PCI)
Type 4b: MI related to stent thrombosis
Type 4c: MI related to in-stent restenosis
Type 5: MI related to coronary artery bypass grafting (CABG)
Markers of highest degree of cardiac specificity
cTnI and cTnT
have different isoenzymes from those found in skeletal muscle, and thus they are specific for cardiac injury
CK Index
CKMB / Total CK x 100
CKMB within reference range and an index < 2.5 is considered
NORMAL
CKMB above reference range and an index > 2.5 suggests
CARDIAC DAMAGE
CKMB above reference range and an index < 2.5 suggests
SKELETAL DAMAGE
During first 24 hours:
at least three samples be drawn for in order to pinpoint the peak of the elevation of CKMB
An elevation of CKMB above ___ with an elevated CK index indicates MI with very high specificity
10 ng/ml
Drug Therapy for AMI
thrombolytics, anti platelets, anticoags, BB, vasodilators, analgesics
Measurement of ___ may be preferred in patients taking sacubitril
NT-pro-BNP
Comorbidities may also affect natriuretic peptide levels
Higher in patients with renal failure, acute coronary syndromes, and diabetes
Lower in patients with obesity
Reference Intervals for Natriuretic Peptides
BNP < 100
proBNP < 50 = < 450
proBNP 50-74 = < 900
proBNP 75+ = < 1800
