Heart Murmurs & Ischemia Flashcards
What happens during S1 in the cardiac cycle?
Closure of the mitral & tricuspid valves
What happens during S2 of the cardiac cycle?
Closure of the pulmonic aortic & pulmonic valves
Do the mitral & tricuspid valve open right after S1 or S2?
S2
What is the most common cause of murmurs?
disease of heart valve
What are the 2 main mechanisms of murmurs?
- Obstructed flow due to stenotic valve
2. Backwards flow through a leaky valve= regurgitation (aka insufficiency)
What are the 3 types of systolic murmurs?
- Mitral regurgitation (MR)
- Mitral valve prolapse (MVP)
- Aortic stenosis (AS)
What are the 2 diastolic murmurs?
Mitral stenosis (MS) Aortic regurgitation (AR)
What artery pulse could you use to help you determine S1 and S2?
Carotid artery
Does the carotid pulse occur during systole or diastole?
During systole
S1 –> carotid pulse –> S2
Which valve is being described? Closed during systole, blood cannot flow backwards from LV to LA
Normal Mitral Valve
What happens during mitral regurgitation?
mitral valve allows backwards blood flow from LV to LV during ALL of systole.
AKA- holosystolic (pansystolic) murmur
When does mitral regurgitation occur during the cardiac cycle? What is the intensity like?
Occurs from S1 to S2
Same intensity throughout the murmur- doesn’t change
Where is mitral regurgitation best heard? Where might it radiate?
Apex
May radiate to axilla or posterior lung bases
What are the causes of mitral regurgitation?
Rheumatic heart disease (immigrants)
Post-myocardial infarction
CT diseases (ex= Marfans)
Mitral Valve Prolapse
Explain a mitral valve prolapse.
Redundant valve tissue with elongated chordae tendinae so the valve balloons up into the LA.
This causes an upward displacement of the mitral valve leaflets during systole
What is heard during a MVP? Where do you hear this best?
Mid-systolic click/ late systolic murmur
- Apex
Is aortic stenosis heard during systole or diastole?
Systole
known as a systolic ejection murmur
What does an aortic stenosis murmur sound like and where is it best heard? Radiates?
Crescendo-decrescendo
- intensity increases then decreases again during systole
- 2nd right intercostal space
- radiates to the neck or heart apex
What are the causes of aortic stenosis?
- congenital bicuspid valve (should be tricuspid)
- more susceptible to wear & tear
- calcific degeneration (in patients over 70)
What are the symptoms of aortic stenosis?
Triad:
- Dyspnea on exertion- 75%
- Angina- 10%
- Presyncope- 10% / Syncope- 5%
How would aortic stenosis lead to heart failure?
Left ventricular outflow obstruction leads to left ventricular hypertrophy –> could lead to heart failure
Explain aortic regurgitation
due to retrograde flow of blood from aorta into the LV- the valve is supposed to be closed but is leaky
When do you hear aortic regurgitation and where is it best heard?
Early diastolic descrescendo murmur
- lower left sternal border- may get patient to lean forward & hold breath
What are causes of aortic regurgitation
Congenital bicuspid valve
Rheumatic heart disease
CT disorders
What can aortic regurgitation lead to?
- volume overload in LV
- combined LV hypertrophy & dilation
- heart failure
Explain mitral stenosis
partially obstructed flow of blood from LA to LV
What does mitral stenosis sound like and where is it best heard? Radiate?
- opening snap followed by a decrescendo diastolic rumble
- apex
- may have patient lie on left side
- doesn’t radiate
What can mitral stenosis lead to?
- Elevated left atrial pressure
- pulmonary hypertension
- eventually right sided heart failure
( blood backs up into lungs causing R sided heart problems)
What is the common cause of mitral stenosis?
Rheumatic fever
What is a cause other than rheumatic fever for mitral stenosis?
- history of long illness following a sore throat in childhood
Which murmur typically has a 20 year latent period before cardiac signs/symptoms are shown?
Mitral stenosis
What do you suggest if you find that a patient has a murmur?
Get an ECHO evaluation
Explain an innocent murmur
- some murmurs are physiologic (benign)
- may originate from a NORMAL aortic or pulmonic valve
- most often in children/young adults or conditioned athletes
What is usually known as a soft systolic murmur?
Innocent murmur
If a patients chief complaint is chest pain, what is your primary goal?
Decide if it is angina or non-angina chest pain
What is angina?
Ischemia heart pain
What is angina caused by?
Imbalance of oxygen supply & demand at myocardium
What happen if myocardial demand is not being met by the coronary arteries?
Intramyocardial vessels dilate to increase blood supply. This extra volume= coronary flow reserve.
What might cause angina?
oxygen demand may not be met due to:
- atherosclerosis
- failure of intramyocardial vasodilation
What are the 2 types of typical angina?
Stable (most common)
Unstable (needs urgent evaluation)
Describe stable angina.
Has a consistent, predictable patterns
- exercise induced
- consistent duration (1-5 mins)
- rest-relieved
- predictable symptoms
- usually in the substernal region = Levine’s sign
Is angina always felt right over your heart?
no- could be felt form umbilicus to eyebrows
What is the most common trigger for typical angina?
Exercise
How is typical angina similar to PAD?
It is often exercise induced and relieved with rest
For typical angina, what would you expect to find in an examination?
- findings are often normal, so you may want to look for indications of atherosclerosis in other areas
examples: - Decreased LE pulses (PAD)
- carotid bruits
Describe unstable angina.
Typically means that angina is worsening due to increased atherosclerosis
- symptoms occur with increased intensity or frequency
- ** no longer require exercise to trigger angina
- plaque > 90&
What is prinzmetal’s angina? What’s the trigger?
Vasospasm of coronary arteries. The triggers are unknown
What might trigger atypical angina?
- cold weather
- heavy meals
- exercise
Who is most likely to experience atypical angina?
elderly
females
diabetics
What is atypical angina?
Dysfunction or occlusion of the “microvasculature”
What are risk factors of atypical angina?
Microvascular disease
Diabetes
Hypertension
Collagen vascular diseases
Does atypical angina require plaque issues or cholesterol issues?
No
What % of patients having an MI experience pleuritic pain?
14%
What % of patients having an MI don’t experience chest pain?
33%
If a patient having an MI doesn’t fall into the category of having no chest pain, or having pleuritic pain what angina equivalents may they experience?
- Dyspnea
- Nausea
- Fatigue
- Pre-syncope
(more common in elderly & diabetics)
What are some symptoms of a MI?
- sympathetic NS is triggered, therefore, they may be:
- tachycardic
- increased BP
- diaphoresis
However, physical exam may be relatively normal
What does acute coronary syndrome refer to?
- it is a blanket term for unstable angina, MI, or sudden cardiac death
- death of myocardium can cause pump failure and/or electrical instability
