22.8.2013 Flashcards
Electrical alternans
Beat to beat variation of QRS complexes by 1mm
Tall waves,DD
Chamber enlargement
Young individuals
Thin,Emaciated individuals
Mastectomy pts
Calculation of heart rate,boxes
100 use small boxes
Causes of low voltage QRS complexes
Obesity COPD Pleural or pericardial effusion Generalised Edema Hypothyroidism Amyloidosis
Causes of electrical alternans
Cardiac tamponade
Poor conduction in ventricles alternating with normal conduction
SVT
Severe myocardial ischemia
Normal intrinsicoid deflection in V1 and V2
<0.03S
Normal intrinsicoid deflection in V5 and V6
<0.05S
Components of QRS
Ventricular activation time
Intrinsicoid deflection
Sequence of ventricular activation
- septum
- free wall of both ventricles
- posterobasal wall of septum and left ventricle
Total duration of septal q wave should not exceed
0.03S
Normal sinus rhythm is indicated by
Upright p wave in lead 2
Measurements of inverted portion of p wave
Less than 1mm in depth and duration
ECG of rt atrial enlargement
Tall(>2.5mm) peaked p waves in leads 2,3,avF
Axis of p wave shifted to right of 60’
P3>P1
Normal p wave duration
<110ms
Causes of rt atrial enlargement
Tricuspid or pulmonary valvular disease
Pulmonary hypertension
Acute pulmonary embolism
Right ventricular failure or hypertrophy
Inverted p wave in V1
Lt atrial hypertrophy
Emphysema
ECG changes of left atrial enlargement
P mitrale(duration>2.5boxes) in lead I,II,aVF,V5,V6
Axis of p wave is shifted to left,P1>P3
Inverted portion of P wave in lead V1 is more than 1mm vertically and horizontally
LVH without increased voltage
Obesity Anasarca Peripheral Edema Increased diameter of chest Emphysema Large breasts Biventricular hypertrophy Amyloidosis Pericardial effusion Pleural effusion Hypothyroidism
Increased voltage not resulting from LVH
Lt Mastectomy
Adolescent boys
Anemia
Thin individuals
Intrinsicoid deflection and ventricular hypertrophy
Delayed in V1 and V2 in RVH
Delayed in V5 and V6 in LVH
ECG changes of LVH due to volume overload
Tall R waves
Prominent Q waves
Tall and upright T waves in V5 and V6
Conduction defects associated with LVH
Incomplete BBB
LAFB
Anti hypertensive medications not effective in reducing LVH
Hydralzine
Minoxidil
ECG finding that is a must for RVH
Rt axis deviation
Lead 1 sign
Seen in emphysema and chronic bronchitis where diaphragm is shifted downwards Small complexes in lead 1 and V6 Poor R wave progression Right axis deviation P pulmonale
Most frequent ECG findings of pulmonary embolism
Sinus tachycardia
Incomplete RBBB
ECG findings in RVH
Rt axis deviation qR in V1 R wave in V1 more than 7mm R wave taller than S wave in V1 Delayed onset of intrinsicoid deflection(V1>0.03) rS complex in V1-V6 with rt axis S1S2S3 pattern in adults
ECG changes of acute pulmonary embolism
Sinus tachycardia,atrial flutter,atrial fibrillation
Rt axis
S1Q3T3
rSR’ pattern in V1 of acute onset
V1 shows QS,qR or R>S pattern
Clockwise rotation with persistent S in V6
P pulmonale
Ta wave exaggeration resulting in ST depression in inferior leads
ST elevation in V1
T wave inversion in V1-V3
ECG findings of biventricular hypertrophy
Katz wachtel phenomenon
P pulmonale with LVH
Voltage discordance
ECG findings of RVH are more prominent in
TOF
congenital pulmonary stenosis
Type A RVH is seen in
Primary pulmonary hypertension
Severe pulmonic stenosis
Mitral stenosis with severe pulmonary hypertension
Type A RVH
Rt axis deviation of more than 120’
Monophasic R waves in V1
Deep S waves in V5,V6
Type B RVH causes
ASD
MS with mild to moderate pulmonary hypertension
Type B RVH
R wave in V1 is slightly taller than S wave
rsr’ pattern in V1
Normal QRS in V5 and V6
Axis is at 90’
Type C RVH causes
Pulmonary disease
Acute pulmonary embolism
Type C RVH
Deep S wave in V1-V6
Axis less than 90’
QRS prolongation in RVH
Doesnot occur unless there is RBBB
