What are the four landmarks of the heart?
- 1. Precordium: area on anterior chest overlying the heart and great vessels
- 2. Mediastinum: midthoracic cavity that contains the heart and great vessels
- - location: 2nd to 5th ICS, right sternal border to left MCL
- 3. Base
- 4. Apex: 5th ICS, 7 to 9 cm left of midsternal line (approximately at MCL)- the heart is rotated so that the right side is anterior and the left side is posterior.
What are the structures of the heart?
- 1. Pericardium: attached to vessels, esophagus, sternum and pleura; anchored to the diaphragm
- 2. Epicardium
- 3. Myocardium
- 4. endocardium
Name two characteristics of the Valves.
- - Unidirectional
- - open and close passively
What are the two atrioventricular valves?
- 1. Left: mitral
- 2. Right: tricuspid
- - chordae tendinea attach the AV valves to the papillary muscles and
- provide stability to valves during systole (rupture of the chordae tendinea may be life threatening.
Name the 2 semilunar valves?
- Right= Pulmonic
- Left= Aortic
Name the two systems in the heart that work together.
1. Conduction system (electrical system that initiates and conducts the heart beat)
2. Hemodynamic system (moves blood through the heart and vessels)
What is the electrical pathway of the conduction system?
- 1. SA node transmitted across the
- 2. AV node
- 3. Bundle of His
- 4. Perkinje fibers in the ventricles
What is an electrocardiogram (ECG)?
reflects the electrical conduction through the heart.
What does the P wave mean?
- - depolarization of atria- spread of stimuli through atria
- - If the SA node isn't firing properly or doesn't fire at all, then the P wave will look abnormal or be absent.
- - the SA node should fire at a rate of 60-100 bpm
- - if a lower pacemaker takes over (e.g. AV node), then the rate will be
What is the PR interval?
time from stimulation of atria to stimulation of ventricles
What is the QRS complex?
depolarization of ventricles- spread of stimuli through ventricles
What is the T wave?
(repolarization of ventricles)- resting phase
final ventricular repolarization
Trace the flow of blood from the lower body to the body again.
- 1. lower body
- 2. inferior vena cava
- 3. RA
- 4. Head and neck
- 5. superior vena cava
- 6. RA
- 7. tricuspid valve
- 8. RV
- 9. pulmonary semilunar valve
- 10. pulmonary arteries (unoxygenated blood)
- 11. lungs/alveoli
- 12. pulmonary veins (oxygenated blood)
- 13. LA
- 14. mitral valve
- 15. LV
- 16. aortic semilunar valve
- 17. aorta
- 18. body
What would happen if backward flow occurred in the right heart?
- - no valves between right atrium and vena cava
- - if pressure in the right atrium is greater than the vena cava, then blood back flows to the veins of the neck and PV system and results in distended neck veins and peripheral edema- r/t valve disease, lung disease, etc.
What would happen if backflow occurred in the left heart?
- - no valves between left atrium and pulmonary veins
- - if pressure in the left atrium is greater than the pulmonary veins, then blood backflows to the lungs and results in pulmonary congestion (e.g. crackles/rales)-r/t valve disease, HTN, etc
What is cardiac output? What's the normal rate?
- CO= HR x SV
- Normal (4-6 L/min)
What is Preload (left ventricular end diastolic volume)?
- increased left ventricular volume causes more stretch on the myocaridal muscle fibers at the end of diastole.
- the goal is the maximize preload (volume) in order to maximize left ventricular contraction and cardiac output.
- however, excessive preload leads to decreased CO and heart failure
What is Frank Starling law?
the greater the stretch of the muscle fibers, the stronger the contraction.
What is afterload (aka SVR or PVR)?
- the opposing pressure the ventricle must generate to open the aortic valve during systole.
- - increased SVR (afterload) causes increased aortic pressures
- - excessive afterload increases myocardial workload and O2 consumption
- - may be caused by arteriosclerosis, HTN, sympathetic nervous stimulation
- (stress), excessive alcohol intake
How are heart sounds produced and which ones are louder?
- - heart sounds are produced by closure of the valves
- - valves are louder on the left side (e.g. mitral valve closure is louder than tricuspid and aortic valve closure is louder than pulmonic)
Where is the aortic valve site located?
2nd ICS, RT sternal border
Where is the pulmonic valve located?
2nd ICS, LT sternal border
Where is the tricuspid valve located?
4th ICS, LT sternal border
Where is the mitral valve located?
5th ICS, MCL
Where is Erbs point located?
3rd ICS, LT sternal border (good location for referred sounds)
What is the best position for hearing aortic murmurs?
sitting and leaning forward is best.
What is the best way for listening to extra heart sounds?
left lateral decubitus position is best.
What makes the first heart sound?
- mitral/tricuspid valves close---> creates S1
- - when aortic/pulmonic valves open (when ventricular pressure exceeds aortic)--> ventricles contract and blood is ejected from ventricles
- ends diastole; begins systole.
What makes the second heart sound?
- aortic/pulmonic valves close ---> creates S2
- - mitral/tricuspid valves open
- - rapid filling phase (passive initial filling of ventricles)
- - atrial kick (atrial contraction ejects last 25% of SV into ventricles)
- - ends systole; begins diastole
Extra heart sounds are also known as?
diastolic heart sounds
S3 makes a sound that sounds like...
- S1---------S2, S3
What does S3 indicate and when does it occur?
- - Indicates ventricular resistance to early passive filling
- - occurs in early diastole (immediately after S2)
What are the causes of S3?
- - decreased ventricular compliance (early sign of HF)
- - high output conditions such as hyperthyroid, pregnancy, etc.
S4 makes a sounds that sounds like....
- S4, S1-------S2
What is a summation gallop?
S3 & S4 combined
What is a Split S1 sound? Is it common or uncommon?
- mitral valve closing before the tricuspid valve due to higher pressures on the left
- - uncommon since closure of tricuspid is usually too faint to hear
- - may be mistaken for an S4
What is a Split S2 sound?
- - aortic valve closing before the tricuspid valve due to higher pressures on the left
- - common
- - changes in intrathoracic pressure with deep inspiration causes asynchronous valve closure.
- - may be mistaken for an S3 although an S3 is not affected by breathing patterns.
- - most prominent at 2nd ICS, left sternal border at peak inspiration (in contrast to an S3 which is best heard at the apex)
What are murmurs and how are they caused?
They are blowing/swooshing sound that occurs with turbulent flow through valves or great vessels.
- Caused by:
- - increased velocity (exercise)
- - decreased viscosity (thin)
- - decreased volume (anemia)
- - defective valves (forward or backward flow)
- - septal defects (ABN openings between chambers)
What are stenotic murmurs?
- occurs when a valve is open.
- - prevents adequate forward flow through thick, stiff valves
- - causes harsh murmurs
What is a regurgitant murmur?
- occurs when a valve is closed
- - also referred to as insufficiency
- - results in backward flow due to poor valve closure
- - causes turbulent sound
What is systolic murmurs?
- heard in systole after S1.
- - aortic/pulmonic stenosis- when semilunar valves are open
- - mitral/tricuspid insufficiency- when AV valves are closed
What are diastolic Murmurs?
- heard in diastole after S2
- - mitral/tricuspid stenosis- when AV valves are open
- - aortic/pulmonic insufficiency- when semilunar valves are closed
How do you know which Murmur you are hearing?
- 1. know if you are in systole or diastole
- one way to tell if you are in systole or diastole is to palpate the carotid pulse while listening to the heart sounds; if you feel the pulse immediately after you hear the heart sound, then you are in systole.
- 2. identify at which valve site the murmur is loudest
- 3. know which valves are open and closed to determine if it is a stenotic or regurgitant murmur
Name three characteristic of Murmurs
- 1. Timing
- - systolic versus diastolic
- - early, mid, or late cycle
- - entire cycle
- - holodiastolic (between S2 and S1)
- - holosystolic (between S1 and S2)
- 2. Intensity (graded 1 [soft] through 6 [loud])
- 3. location (valve site)
What is an innocent murmur?
- it is a functional murmur.
- - no valve, cardiac or other pathology
- - common in childhood (usually due to increased blood flow)
Chest Pain etiology would entail....
- 1. Cardiac (angina, MI, mitral valve prolapse)
- 2. Pulmonary (pneumonia, pleurisy, embolis)
- 3. Pericardial (pericarditis)
- 4. Musculoskeletal/chest wall (costochondritis, arthritis)- hurts with palpation
- 5. Gastrointestinal (may mimic MI)- ulcer, hiatal hernia, esophagitis, indigestion
- 6. Neurotic- anxiety
You would include when describing symptoms:
- 1. Onset: at rest, with activity, after eating, etc.
- 2. Location: substernal, localized versus radiating
- 3. Duration
- 4. Character (burning, sharp/stabbing, crushing, pressure, etc. )
What is angina, describe the symptoms.
- angina: myocardial ischemia-imbalance between 02 supply and demand (thus, more common with exercise)
- - SX: chest discomfort with or without radiation, SOB
- - should resolve in a couple of minutes with rest and or treatment (NTG) --->
- may progress to an MI if not treated - prolonged symptoms may indicate an MI
What is an myocardial infarction?
- heart attack
- - SX: similar to angina; may also have diaphoresis, N/V, palpations, sense of impending doom
What are some atypical symptoms of CAD?
- - SOB
- - sharp chest pain
- - fatigue
What are risk factors for CAD? (6)
- 1. age (males > 45, females >55 or postmenopausal)
- 2. HTN or hypertensive treatment
- 3. Smoking
- 4. Hyperlipidemia
- 5. Diabetes
- 5. Family history of premature CAD in 1st degree relative (male <55; female <65)
Name nine other subjective data components?
- 1. SOB caused by dynspnea, DOE, PND and orthopnea
- 2. cough
- 3. fatigue
- 4. Syncope
- 5. Edema and Nocturia (recumbent position increases venous return to heart which increases renal blood flow --->increases U/O)
- 6. Past hx (HTN, CAD, DM, obesity, congenital heart disease, genetically transmitted disease.
- 7. Personal habits
- - diet (high fat, sodium)
- - smoking (vasoconstricts)- increased heart rate, myocardial workload and
- O2 consumption.
- - ETOH (increases afterload) --cardiac depressent causing sympathetic compensatory response
- - exercise (increases HDL, myocardial muscle tone)
- - medications (digitalis, diuretics, beta blockers, calcium channel blockers, etc.)
The objective data (physical exam) includes:
- 1. assess for cyanosis or clubbing
- 2. neck vessels (inspect, palpate and auscultate)
- - carotid arteries
- - jugular veins
- 3. Precordium
- 4. Auscultate
How do you assess for carotid arteries?
- - visualized at top of neck near mandible
- - palpate in lower 1/3 of neck between trachea and SCM muscle (avoid carotid sinus which slows HR)
- - Palpate one artery at a time
- - pulse strength 2+ (diminished with decreased stroke volume)
- - auscultate for bruits
How do you assess for jugular veins?
- - indirect measure of RA pressure
- - jugular veins reflect changes in filling pressures
- - no valves between jugular veins and RT atrium
- - increased RT atrial pressure= JVD
- - external jugular vein (lies over SCM)
- - internal jugular vein (IJV)- underneath and medial to SCM
- - more reliable than external jugular vein for measuring RA pressure (attached directly to SVC)
- - can't see IJV (can only see waves or fluctuations)
- - slightly rotate head to side (look for pulsations at the right base of the
- neck (caused by the IJ moving the SCM)
How do you differentiate carotids from internal jugular veins?
- Internal jugular veins:
- - pulsation visible but not palpable
- - two undulating waves or fluctuations
- - Palpable pulsation (one brisk pulsation wave)
How do you assess jugular venous distention and Jugular venous pressure?
- - Raise HOB 30-45 degrees and locate the top of the IJ pulsation in the Right neck
- - Jugular Venous Distention
- - norms: 3-4 cm above sternal angle
- - Jugular Venous Pressure (estimate of RA pressure)
- - JVP= JVD + 5cm (distance of R atrium from sternal angle)
- - Norms: < 9 cm
What is an abnormal or normal finding of hepatojugular reflex?
Normal: (when pressure is applied to the liver border, the jugular vein on the right side of the neck will distend for a few seconds, then return to normal)
Abnormal: jugular veins will remain elevated as long as pressure is applied to liver-suggestive of CHF
For the Precordium we will inspect and palpate for:
- 1. Apical Pulse
- - located at 4th or 5th ICS, left MCL)- palpable in 1/2 of adults
- (decreased with obesity and thick chest walls)
- - if shifted farther to the left, this may indicate cardiomegaly (enlarged heart)
- 2. Heaves (lifts)
- 3. Thrill (palpable vibrations)
What is a heave?
- sustained forceful thrusting of ventricle during systole
- visualized and palpated at the apex
What is a thrill?
- associated with loud harsh murmurs
- palpate across precordium
What are you auscultating for?
- 1. rate (norm 60-100)
- 2. rhythm (regular; regular-irregular; irregular)
- 3. heart sounds-listen to each valve with the diaphragm and bell
What are the heart sounds we are auscultating for?
- 1. S1
- 2. S2
- 3. Split Sounds
- 4. Gallops (S3, S4)
- 5. Rubs and clicks
- 6. Murmurs
S1 is loudest at which site?
- The apex
- - corresponds with R wave on ECG
- - Diminished sounds (pericardial effusion, obesity, emphysema)
S2 sounds are loudest at the...
- - aortic valve sounds best heard with the pt sitting and leaning forward
How do you auscultate for gallops?
turn pt to left side; often more pronounced over apex
Where do we auscultate for murmurs?
listen over the valve sites and note any radiation across the precordium