Heart Murmur Types Flashcards
(16 cards)
What is a heart murmur?
- The sound produced when blood flowing through the heart is turbulent
- The flow of blood is usually smooth, however, abnormalities may cause turbulence, which creates a sound (murmur)
What are the causes of heart murmurs? (4)
- Blood flowing through an abnormal narrowing (AS, MS, PS)
- Blood flowing in the wrong direction through the heart, and mixing with blood flowing in the normal direction (MR, TR)
- Abnormal connection between 2 different parts of the heart (atrial septal defect, patent ductus arteriosus)
- Blood flowing faster through the heart (functional murmurs in sepsis and thyrotoxicosis)
Examples of murmurs that are transmitted? (2)
- Aortic stenosis
2. Mitral regurgitation
Where does aortic stenosis radiate to?
Carotid arteries
Where does mitral regurgitation radiate to?
Axilla
Describe systole
- Ventricles contract
- Aortic and pulmonary valves open to allow blood to flow through – narrowing => systolic murmur
- Mitral and tricuspid valves close shut to prevent blood flowing backwards – regurgitation => systolic murmur
Describe diastole
- Ventricles and atria relax at the start of diastole (early diastole)
- Aortic and pulmonary valves shut to prevent blood from flowing backwards – regurgitation => early diastolic murmur
- Atria contract towards the end of diastole (mid or late-diastole)
- Mitral and tricuspid valves open to allow blood flow to ventricles – narrowing => mid, late or end-systolic murmur
What are the heart sounds?
S1 (first heart sound)
S2 (second heart sound)
Describe S1 (first heart sound)
- Caused by the closure of the mitral and tricuspid valves
- Denotes the start of systole
- Peripheral pulse will be felt at the same time or just after S1
Describe S2 (second heart sound)
- Caused by the closure of the aortic and pulmonary valves
- Denotes the end of systole and start of diastole
- The pulmonary valve may close just after the aortic valve
What murmurs are heard in systole?
- Aortic and pulmonary stenosis
- Mitral and tricuspid regurgitation
- Mitral valve prolapse (gives a systolic murmur with an opening click)
What murmurs are heard in early diastole?
Aortic and pulmonary regurgitation
What murmurs are heard in mid/ late-diastole?
Mitral and tricuspid stenosis
What are the characteristics of systolic murmurs?
- Ejection systolic (crescendo-decrescendo)
2. Pansystolic
What are the causes of ejection systolic murmurs?
- Aortic and pulmonary stenosis
- Aortic sclerosis
- Hypertrophic obstructive cardiomyopathy (HOCM)
What causes pansystolic murmur?
Mitral and tricuspid regurgitation
