These are Murmurs which occurs during any part of diastole
1.Early diastolic murmurs
They begin with or shortly after second heartsound S2 as soon as corresponding ventricular pressure falls enough below that in the aorta or pulmonary artery
Causes of early diastolic murmurs:
- AR (aortic regurgitation)-heard in right 2nd ICS (interscapular space) and Erb’s area,increases on expiration
- PR (pulmonary regurgitation) -left 2nd ICS,increases on inspiration
2.Mid diastolic murmurs
Arise from mitral or tricuspid valves,they occur during early ventricular filling , produced due to disproportion between valve orifices and flow rate.
Common causes :Mitral stenosis,Tricuspid stenosis
Uncommon causes:
- Carey - Coombs’ murmur
- Austin-Flint’s murmur
- Acute severe
- Ritan’s murmur
- Flow MDM in high output states
Flow MDM across tricuspid valve occur in
- Atrial septal defect
- Tricuspid regurgitation
- Total anomalous pulmonary venous connection
Flow MDM across mitral valve is seen in
- Ventricular septal defect
- Patent ductus arteriosis
- Mitral regurgitation
- Aortic regurgitation
3.Late diastolic/presystolic murmurs
Begin during period of ventricular filling and follows atrial contraction and therefore occur in sinus rhythm
Causes
- Mitral stenosis
- Tricuspid stenosis
- Atrial myxomas
- Complete heart block
