This document provides an overview of various diagnostic tools used in cardiology, including electrocardiography (ECG), non-invasive cardiac imaging modalities like echocardiography and nuclear imaging, and invasive diagnostic procedures like cardiac catheterization and coronary angiography. It describes the basic principles, clinical applications, and abnormalities detected by each diagnostic modality.

1. DIAGNOSTIC TOOL
BY
KAPIL MOHAN
7TH BATCH,INTERN
JMCTH
CVS

2. TYPES
1. Ecg
2. Non invasive cardiac imaging
a. echocardiography
b. nuclear cardiology
c. mri/ct imaging
3. Diagnostic cardiac catheterization &
Coronary angiography

3. ECG/EKG
Graphical recording of electric potentials
generated by heart, signals detected by means
of metal electrodes attached to extremities and
chest wall.
Clinincal utility:
Immediate, noninvasive, inexpensive, highly
versatile test

4. ECG LEADS
12 conventional ECG leads are there divided
into two groups : 6 limb leads (extremity) 6
chest leads ( precordial )
Limb leads record potentials transmitted onto
frontal plane and chest leads record potentials
transmitted onto horizontal plane.

7.  Ecg leads are configured so that
+ive(upright) deflection is recorded if wave of
depolarisation spreads towards postive pole
of lead and –ive deflection is recorded if
wave spreads towards negative pole.

8. EINTHOVEN TRIANGLE
 The 3 standard limb leads form an equilateral
triangle at centre of heart.

9. GENESIS OF ECG
 P wave
 QRS complex
 T wave
 U wave

12. RHYTHM OF HEART
 Normal rhythm is sinus rhythm.
 Cardiac pacemaker: SA node (60-100 bpm)
 Other potenial pacemakers are known as
ectopic or subsidary pacemakers
 atrial/junctional pacemaker- 40-60bpm
 Ventricular pacemaker:20-40bpm

13. IRREGULARITY
Regeularly irregular- premature beats during
any rhtyhm , bigeminal rhythm
Irregularly irregular – atrial fibrillation( disrete p
waves of sinus rhythm are replaced by
numerous, small fibrillating waves.
Ventricular fibrillation- rapid small deformed
deflections

14. R-R INTERVAL- HEART RATE
 Heart rate- number of heart beats / min.
 In ECG- number of cardiac cycles occuring
during a 60 sec continuos recording of ecg.
 Method: 300/ no. of large squares between
two R waves.

15. P WAVE
 Produced by atrial depolarisation
 Normally upright in most of ecg leads except
avR ( dirction of atrial activation is away from
this lead )
 Height : < 0. 25 mv
 width : < 0.10 sec

16. ABNORMALITIES OF P WAVE
 Absent
atrial fibrillation
atrial flutter( saw toothed apperance of
baseline)
venticular tacycardia
Hyperkalemia
 Broad p wave
left atrial enlargement >0.10 sec

17.  Inverted p wave
junctional rhythm
by pass tract
 Tall p wave
right atrial enlagement
p pulmonale (pulmonary hypertension)
p congenitale ( congenital heart disease )

18. QRS COMPLEX
 Produced by ventricular depolarisation, r
wave is positive while q and s waves are
negative
 Q wave – seen in L1, aVL, V5, V6
(physiological)
width:<0.04sec, depth <25%of R wave
pathological q wave due to necrosis of heart
muscle or MI and criteria is ≥0.04 sec , >1/4
of R wave, +nt in other leads than in those
with

19.  R wave : almost all the leads except aVR.
Gradually increases as we move from V1 to
V6(V1 ≤0.4 mV ; V6 ≤2.5 mV)
Abnormalities : tall R wave
In V1 lead: rvh, rbbb, wpw syndrome, true
posterior wall infarction
In V6: lvh, lbbb

20. S WAVE
 Negative deflection that follows R wave.
 Normally greater than R wave in V1: smaller
than R wave in V6

21. ABNORMAL QRS COMPLEX
 Normal width : 0.04 sec to 0.08 sec
 >0.08 sec
 Bundle branch block: rbbb, lbbb
 Intraventricular conduction defect:
antiarrhythmic drugs eg amiodarone,
electroltye imbalance eg hyperkalemia,
myocardial disease eg myocarditis

22.  Ventricular preexcitation : wpw syndrome, lgl
syndrome
 Wide QRS arrhythmias :atrial fibrillation with
VT

23. T WAVE
Produced by ventricular depolarisation
Normally upright in most leads . Inverted in
aVR along with inversion of P wave and QRS
complex
Also in lead V1, V2, V3, L3
Amplitude : ≤5mm in limb leads; ≤ 10mm in
precordial leads.

24.  Abnormalities of T wave
 Inverted T wave :
physiological- heavy metals, smoking, anxiety,
tachycardia, hyperventilation
extracardiac causes- systemic ( shock,
haemorrhage), cranial (CVA) , abdominal
(pancreatitis, cholecystitis), respi ( pulmonary
embolism ), endocrine ( hypothyroidism)

25.  Specific causes-
 1º abnormality- pharmacological
(digitalis),metabolic(cardiomyopathy),
pericardial( pericarditis, pericardial effusion ),
ischaemic ( infarction, coronary insufficiency)
 2º abnormality- venticular hypertrophy, bbb,
wpw syndrome

26. THE INTERVALS
 P-R interval
 Q-T interval

27. P-R INTERVAL
 From onset of P wave to beginning of QRS
complex.
 Normal PR interval – 0.12 – 0.20 sec

28. ABNORMALITIES OF PR INTERVAL
 Prolonged PR interval >0.20 sec
Indicates increased AV nodal conduction
delay
or 1st degree AV block.
Causes- vagal domination in athelets, ARF,
CAD,
drugs acting on av node eg digitalis, CCBs

29.  Reduced PR interval
 Causes- AV nodal or junctional rhthym, wpw
syndrome with pre-excitation
 Variable PR interval
 causes- type 1 , 2nd degree av block,
complete av block, wandering pacemaker
rhtyhm

30. AXIS DEVIATION
 Right axis deviation
 Left axis deviation

31. RIGHT VENTRICULAR HYPERTROPY
 Criteria for diagnosis
 R wave in V1 :> 4mm
 R:S in V1:>1
 S wave in V6 >7mm
 R in V1+ S in V6: >10 mm

32. CAUSES OF RVH
Pulmonitary HTN
Congenital heart disease
Chronic cor pulmonale
Pulmonary valve stenosis
Isolated congenital PS
PS of TOF

33. LEFT VENTRICULAR HYPERTROPHY
 Voltage criteria
 S in V1 or V2+ R in V5 or V6 >35 mm
(sokolow)
 R in V5+V6>25 mm; R in aVL >11 mm
(framingham)
 S in V3+ R in aVL >28 mm (men ), >20mm
(women ) (cornell)

34. CAUSES OF LEFT VENTRICULAR HYPERTROPHY
 Systolic LV overload- systemic HTN, AS
(valvular, subvalvular), coarction of aorta,
HOCM
 Diastolic LV overload –AR, MR,VSD,PDA

35. NON INVASIVE CARDIAC IMAGING
 Echocardiography
 Nuclear cardiology
 MRI/CT imaging

36. ECHOCARDIOGRAPHY
 Types
 2D
 Doppler
 Stress
 Transesophageal

38. 2D ECHOCARDIOGRAPHY
 Principle-ultrasound reflection off cardiac
structures to produce images of heart.
 For TTE (transthoracic ) echocardiogram,
imaging is performed with a handheld
transducer placed directly on chest wall
 Advantage – instantaneous images of
cardiac structures is obtained for
interpretation
 Ideal for cardiac emergencies.

40.  Useful in
 LV hypertrophy
 Hypertropic cardiomyopathy
 Valve abnormalities – gold standard . ex- MS
 Pericardial disease – modality of choice for
pericardial effusion.
 Intracardiac masses. Appear as echo dense
strutures.

41. DOPPLER ECHOCARDIOGRAPHY
 Principle:uses ultrasound reflecting off
moving rbc to measure the velocity of blood
flow across valves, with cardiac chambers
and through great vessels.
 Different color indicates different direction of
blood flow
 Red towards and blue away from transducer
with green superimposed when there is
turbulent flow.

42.  Modified Bernoulli equation:
 Pressure change=4 times (velocity)²
 High velocity of blood flow directed along the
line of doppler beam is measured such as in
valve stenosis, valve regurgitation, or
intracardiac shunts.
 These high velocities are used to determine
intracardiac pressure gradients

44. STRESS ECHOCARDIOGRAM
 2D and Doppler are usually performed with
patient in resting state. Further information
can be obtained by reimaging during either
exercise or pharmacologic stress.
 Indications – confirm suspicion of IHD and
determine extent of ischaemia.
 Exercise testing done using either upright
treadmill or bicycle, pharmacologic testing by
infusion of dobutamine.

46. TRANSESOPHAGEAL ECHOCARDIOGRAM
 Used when limited information is obtained
from TTE, TEE is useful.
 Used for
 Diseases of aorta- aortic dissection
 Atrial thrombi
 Patent foramen ovale
 Presence of vegetations in infective
endocarditis

47. NUCLEAR CARDIOLOGY
 Nuclear (or radionuclide ) imaging requires iv
administration of radiopharmaceuticals (
isotopes or tracers )
 Once injected , isotope traces physiologic
process and undergoes uptake in specific
organs. Radiation is emitted in form of
photons, generally gamma rays.
 Special camera detects these photons and
creates images via computer interface

48.  Most commonly used technologies are
 1. SPECT (single photon emission computed
tomography )
 2. PET ( positron emission tomography )
 Both differ in intrumentation, acquisition,
resolution and nuclides used.

50. MRI IMAGING
 Principle- based on magnetic properties of
hydrogen nuclei.
 Larger vessels can be visualised on mri
without contrast agents, gadolinium is
frequently employed as contrast agent to
produce magnetic resonance angiograms.
 Both static and cine images can usually be
obtained using electrocardiographic
triggering, often within short breadth holds of
10-15secs.

51.  MRI is of great value in defining anatomic
relationships in patients with complex
congenital heart disease and
cardiomyopathies

53. CT SCAN
 Fast simple, noninvasive technique that provide
images of myocardium and great vessels with
excellent spatial resolution and good soft tissue
contrast.
 Important clinical applications
 Pericardial calcification
 Cardiac masses, particularly those containing
fat or calcium.
 Suspected arrhythmogenic right ventricular
dysplasia

54.  Suspected pulmonary embolism –
examination of choice.
 Aortic dissetion

56. INVASIVE CARDIAC IMAGING
 Types:
 Cardiac catheterization
 Coronary angiography
 Both are indicated to evaluate the extent and
severity of cardiac disease in symptomatic
patients and to determine if medical, surgical,
or catheter based interventions are
warranted

57. .

58. TECHNIQUES
 Dependent upon patient’s symptoms and clinical
condition with some direction provided by
noninvasive studies.
 Vascular access- percutaneous technique used
to enter femoral artery and vein as the preferred
access site for left and right heart
catherterization , respectively.
 Flexible sheath is inserted into vessel over a
guidewire, allowing diagnostic catheters to be
introduced into vessel and advance towards
heart using fluroscopic guidance.

59.  Other blood vessels being used are-
 Brachial or radial artery-
 (normal allen’s test confirming dual blood
supply to hand from radial and ulnar arteries
is prerequisite to access this site.

60.  Hemodynamics –shape and magnitude of
pressure wave forms provides important
diagnostic information.
 In absence of valvular heart disease, atria
and ventricles are “one chamber” during
diastole when tricuspid and mitral valves are
open while in systole when pulmonary and
aortic valves are open, ventricles and their
respective outflow tracts are considered “one
chamber”.

61.  When aortic stenosis is present , there is
systolic pressure gradient between left
ventricle and aorta.

64. THANK YOU !!!