Cardiology Flashcards
PR interval
0.12-0.20
PR segment
0.05-0.12
QRS complex
0.08-0.12
QT interval
Less than or equal to 0.45 in males, 0.46 in females
Corrected QT
Bazett’s formula: QT interval/square root of RR in seconds
When to correct for QT
Tachycardia or bradycardia
How to measure heart rate for regular rhythm
1500/number of small boxes from R-R
1 small box: second/s
0.04
5 small boxes (1 big box): second/s
0.2
1 small box: mm
1
5 small boxes (1 big box): mm
5
Normal axis
-30 to 100
Examples of LAD (4)
1) LVH
2) Inferior wall MI
3) Hyperkalemia
4) Normal variant
Examples of RAD (6)
1) RVH
2) Anterolateral wall MI
3) Pulmonary embolism
4) Chronic lung disease
5) ASD, VSD
6) Normal variant in children and thin adults
Leads for eyeballing of axis
1) Lead I
2) aVF
Heart rate in sinus rhythm
60-100bpm
Heart rate in junctional rhythm
40-60bpm
Heart rate in idioventricular rhythm
15-40
Anterior wall: Supplied by
LAD
Anterior wall: Leads
v1-4
Anteroseptal wall: Supplied by
LAD
Anteroseptal wall: Leads
V1-2
Anterolateral wall: Supplied by
LCX
Anterolateral wall: Leads
V4-6
Lateral wall: Supplied by
LCX
Lateral wall: Leads
I, aVL
Inferior wall: Supplied by
RCA
Inferior wall: Leads
II, III, aVF
Vessels that comprise the largest total cross-sectional and surface area of circulation
Capillaries
T/F: Venules have autonomic innervation
T
Correponds to the distensibility of blood vessel
Capacitance/compliance
Artery vs vein: Greater capacitance
Vein
Most important determinant of pulse pressure
Stroke volume
Palpation mtd of BP measurement: Artery used
1) Brachial
2) Radial
Palpation mtd of BP measurement: Inflate the cuff ___ mmHg above the point where loss of pulse is noted
30
Auscultation mtd of BP measurement: Inflate cuff ___ mmHg above systolic pressure
30
Palpation mtd of BP measurement: Rate of decrease in pressure should be
2-3 mmHg/sec
Korotkoff phase: Onset of tapping
Phase 1
Korotkoff phase: Reappearance of tapping sound
Phase 3
Korotkoff phase: Disappearance of sound
Phase 5
Korotkoff phase: 10-15mmHg lower than previous phase during which a murmur may be heard after tap
Phase 2
Korotkoff phase: Muffling of heart sound
Phase 4
Normal BP difference of both arms
Less than 10 mmHg
UE vs LE: Higher BP
LE
BP is __mmHg higher in legs than arms
20
Orthostatic hypotension: Fall in SBP by __mmHg
20
Orthostatic hypotension: Fall in DBP by __mmHg
> 10
Effect of inspiration to SBP
Decrease
Exaggerated fall in SBP with normal respiration
Pulsus paradoxus
mmHg fall in pulsus paradoxus
10mmHg or more
Slow rise in arterial pulse
Pulsus tardus
Pulsus tardus is seen in
Aortic stenosis
Non-cardiac causes of rapid rise in arterial pressure or bounding pulse (3)
1) Thyrotoxicosis
2) Pregnancy
3) Anemia
Cardiac causes of rapid rise in arterial pressure or bounding pulse (3)
1) PDA
2) AR
3) Coarctation of the aorta
Twice beating or double-peaked arterial pulse
Pulsus bisferiens
Condition: Pulsus bisferiens
AR
Single most common cause of heart failure
CAD
***Most common cause of pump failure hence CHF
Myocardial hypertrophy usually sec to htn
Measure of LV function
EF
Heart failure with depressed EF
Systolic failure
Heart failure with preserved EF
Diastolic failure
Treatment for systolic failure
Digoxin
Most common manifestation of left-sided heart failure
Pulmonary congestion and edema
Heart failure cells
Hemosiderin-laden macrophages
Most common cause of right-sided heart failure
Left-sided heart failure
Left vs right sided heart failure, etiology: Pulmonary emboli
Right
Left vs right sided heart failure, etiology: Any disease interfering with pulmonary ventilation
Right
Left vs right sided heart failure, etiology: Cystic fibrosis
Right
Left vs right sided heart failure, etiology: Ischemia
Left
Left vs right sided heart failure, etiology: Systemic htn
Left
Left vs right sided heart failure, etiology: Myocardial disease/cardiomyopathy
Left
Right-sided heart failure caused by pulmonary htn from intrinsic lung dse
Cor pulmonale
Right-sided heart failure results on __ in the liver
Chronic passive congestion
Histologic morphology of liver in right-sided heart failure
Centrilobular congestion and atrophy of central hepatocytes described as nutmeg liver
Functional capacity class: Ordinary physical activity does not cause undue fatigue
I
Functional capacity class: SLIGHT limitation. Ordinary physical activity results in fatigue.
II
Functional capacity class: MARKED limitation. Less than ordinary activity causes fatigue.
III
Functional capacity class: Symptoms present even at rest
IV
Cardinal symptoms of heart failure (2)
1) Fatigue
2) Shortness of breath
Periodic respiration or cyclic respiration
Cheyne-Stokes
Mgt of heart failure with depressed EF (less than 40%)
1) Screen and treat comorbidities
2) Stop smoking and limit alcohol
3) Avoid extremes of temp and heavy physical exertion
4) Diuretics
Most common sustained arrhythmia
Atrial fibrillation
Typical rate of afib
120-160bpm