TEST ASSOCIATED WITH CARDIAC DISORDER

1. TEST ASSOCIATED
WITH CARDIAC
DISORDER
Presented By
Pooja
Dept. Pharmacy Practice
Grace College Of Pharmacy

2. ELECTROCARDIOGRAPHY
Electrocardiography is the recording of the electrical activity of the heart on an
electrocardiogram(ECG).
CONDUCTION SYSTEM OF HEART

3. • Electrocardiography is based on the measurement of change in forces that result from
depolarization and repolarization of cells in the conduction system and heart muscle.
The standard external 12-lead ECG uses : two sets of leads: limb and chest.
The six limb leads , Limb lead nomenclature is as
• follows: lead I, right arm/left arm
• lead II, right arm/left leg
• lead III , left arm/left leg.
• Altering resistances create the augmented limb leads, which are called aVR
(augmented vector right ), aVL, and aVF.
Unipolar chest leads are
• positioned across the chest and labelled V1 to V6

5. The classic ECG pattern of myocardial infraction is reflected by three changes
1.T-wave inversion
2.ST-segment elevation
3. Appearance of Q wave

6. LABORATORY TEST
Biochemical Cardiac marker:
Infraction of myocardial cells disrupt membrane integrity, leaking intracellular
macromolecules into the peripheral circulation where they are detected.
Several biochemical cardiac markers are:
CARDIAC SPECIFIC TROPONINS
CREATINE KINASE
CREATINE KINASE ISOENZYME
MYOGLOBIN

7. CARDIAC SPECIFIC TROPONINS
Cardiac specific troponins biochemical markers of choice in the evaluation of ACS.
ᴥ Cardiac Specific Troponin I : Diagnostic level : <1.5ng/mL
ᴥ Cardiac specific troponin T : Diagnostic value :<0.1ng/ml
Troponin is a protein complex consist of three subunits :
ᴥ Troponin C (binds to calcium ions to produce a conformational change in TnI),
ᴥ Troponin T (binds to tropomysin, interlocking them to form a troponin-tropomyosin complex).
ᴥ Troponin I(binds to actin in thin myofilaments to hold the troponin-tropomyosin complex in place),
Three subunits located along thin filament of myofibrils and they regulate ca2+mediated actin and
myosin for the contraction of cardiac muscles.
MARKER Range of time to
initial level
elevation (hrs.)
Mean time to
peak elevations
Time to return to
normal range
cTnI 3-12 24 hrs. 5-10 days
cTnT 3-12 12 hrs.- 2 days 5-14 days

9. CREATINE KINASE
ᴥ Normal range : 40-200 IU/L(Male), 35-150 IU/L (female )
Creatine Kinase is an enzyme that stimulate the transfer of high-energy phosphate
groups .CK found in skeletal muscles ,myocardium and the brain .
ᴥ Skeletal muscles causes: muscle dystrophy, Rhabdomyolyis ,seizure , trauma .
ᴥ Cardiac causes: Myocarditis, Pericarditis ,AMI.
ᴥ Other causes : Hypothyroidism ,Renal failure, Cerebrovascular accident.
ᴥ Medication : Ethanol, Lithium
MARKER Range of time to initial
level elevation (hrs.)
Mean time to peak
elevations
Time to return to
normal range
CK 4-8 24 hrs. 3-4 days

10. CREATINE KINASE ISOENZYME
Normal range : CK-MB<12 IU/L
There are three isoenzyme three found in different sources :
CK-BB (brain , lungs, intestine )
CK-MM (skeletal and cardiac muscles)
CK-MB (predominantly in the myocardium but also in skeletal muscles .
CK-MB specific for myocardial tissue used for diagnosis of AMI.
The diagnosis of AMI is strongly suggested when CK-MB concentration was greater than
10 IU/L.
MARKER Range of time to initial
level elevation (hrs.)
Mean time to peak
elevations
Time to return to
normal range
CK-MB 3-12 24 hrs. 2-3 days

11. To differentiate between cardiac and non cardiac cause ,Relative index is measured can
be used.
RI = Measured CK-MB (ng/mL)x 100
Total CK Activity(International unit)
* an index greater than 2 is suggestive of myocardial necrosis .
MYOCARDIAL CAUSES
Myocardial infraction
Myocarditis
Pericarditis

12. MYOGLOBIN
Myoglobin is low molecular-weight heme protein found in cardiac and skeletal muscle.
The early rise of myoglobin levels after onset of symptoms makes it the most
appropriate and convenient test for early detection of AMI.
MARKER Range of time to initial
level elevation (hrs.)
Mean time to peak
elevations
Time to
return to
normal range
Myoglobin 1-4 6-7 hrs. 24 hrs.

13. LACTATE DEHYDROGENASE
Normal range : 100-210 IU/L
Lactate dehydrogenase is an enzyme that catalyzes the reversible formation of lactate
from pyruvate .
LDH have five major isoenzyme (LDH1-LDH5)
Heart contain mainly LDH 1 and to lesser extent LDH 2. Elevation of LDH1 :LDH2
greater than one was used in the differential diagnosis of AMI.
MARKER Range of time to initial
level elevation (hrs.)
Mean time to peak
elevations
Time to return to
normal range
Lactate Dehydrogenase
(LDH)
24-48 2-3 days 8-14days

14. ASPARTATE AMINO TRANSFERASE:
Normal range : 0-37 IU/L (male), 0-31 IU/L(female)
Have poor specificity.
MARKER Range of time to initial level
elevation (hrs.)
Mean time to peak
elevations
Time to return to
normal range
AST 12 24-48 hrs. 3-4 days

15. OTHER BIOCHEMICAL MARKER
C-REACTIVE PROTEIN
CRP is a non specific enzyme that is released in presence of inflammatory process
caused by various aetiology .
Inflammation plays a very important role in the pathophysiologic process leading to
atherosclerosis plaque rupture ,serum and plasma level of CRP is are elevated in patient
with ACS and CAD.
Natriuretic Peptides:
Natriuretic peptides are naturally-secreated hormones that are released by various cell
in response to increased volume or pressure .
It include ;
Atrial natriuretic peptide(ANP)
B-type natriuretic peptide
C-type natriuretic peptide

16. ANP and BNP are known cardiac specific peptide
They are both structurally similar and exert potent diuretic effect and vascular smooth
muscle relaxing effect.
It is found in higher concentration in cardiac ventricles and secreated by left ventricular
myocytes in response to volume overload and increased ventricular tension.
PREPRO BNP (Precursor of BNP)
PRO BNP
C-terminal pro BNP N-terminal pro BNP (NT-proBNP)
BNP and NT pro BNP levels are measured for evaluation of patient suspected of having
heart failure ,assessment of severity of heart failure.

17. B-type natriuretic peptide (BNP)
Diagnostic cut off :100pg/mL
BNP level greater than 100 pg/ml is 90% sensitive for diagnosis of heart failure.
NT-pro BNP
NT-pro BNP are more stable than BNP .They are typically higher than BNP and are
elevated in elderly and accordingly the diagnostic cut off level are made :
Diagnostic cut off : 125pg/ml for patient <75 years of age; 450pg/mL for patient >75
years of age

18. IMAGING STUDIES :
1. CHEST ROENTGENOGRAM :
• Chest radiography provides an early estimation of the size of the left heart chambers
• Chest roentgenogram findings of heart failure include cardiac enlargement ,vascular
redistribution, interstitial and alveolar edema and pleural effusions.
• Cardiac enlargement on chest roentgenogram in patients with heart failure is
associated with a higher morbidity rate
2.ECHOCARDIOGRAPHY
• Echocardiography is based on sound transmitted to and through the heart .
• Transthoracic echocardiography involve sound waves from a transducers positioned
on the anterior of the chest directed across the cardiac tissues. The sound is reflected
back in different frequencies and image of cardiac anatomy are displayed on monitor .
• Clinical uses include anatomic assessment of the heart and functional assessment of
cardiac chamber.

19. NONINVASIVEE STRESS TESTING
Exercise stress testing
Physical exercise is performed using graded exercise protocol on a treadmill .Most
widely used protocol is the Bruce protocol.
Endpoint is symptoms of exhaustion, decrease in systolic BP ,ST segment depression on
ECG.
Patient who are unable to exercise may be stressed by pharmacologically using a
a. Vasodilating agent (adenosine )
b. Positive inotropic agent (dobutamine)

20. Cardiac Catherization
Introduction of catheter through the femoral or brachial artery advanced to heart
guided by fluroscopy .
Determines intracardiac pressure, hemodynamic data and blood flow in the heart
chamber.
Coronary angiography
Contrast media is injected into the coronary arteries .X-ray exposure of the coronary
artery are examined to asses the location and severity of coronary atherosclerotic
lesions.
Left Ventriculography :
Contrast media is injected into the left ventricles to asses its structure and function

21. Nuclear imaging :
Nuclear imaging involves the injection of trace amounts of radioactive elements.
Nuclear imaging is use to asses blood flow through the heart and myocardial perfusion .
Computed tomography :
CT involves in intense ,focused electron and X ray tube inside the machine rotates around
body and collects images of heart and chest.
Cardiac CT scan useful in assessment of cardiac structure and pulmonary disease
Magnetic resonance imaging :
MRI involve placing patient in device generating a powerful magnetic field and passing
radio waves, waves are detected by a scanner and converted to images.
Asses congenital, aortic, precordial diseases ,tumours and intravascular thrombus.

22. Positron emission tomography
PET is a nuclear imaging technique capable of measuring myocardial blood flow and
cellular metabolism of substrate such ass fatty acids, glucose and oxygen in vivo.
Blood pooling image :
Used to evaluate ventricular wall motion and function as well as left ventricular volume.
Human serum albumin or patient red blood cells are tagged with Tc-99m and injected
IV into the patient. A scintillation camera records and multiple images are taken.

23. • REFERENCE:
Basic Skill In Interpreting Laboratory Data ,Fourth Edition BY MARY LEE Page no :207