From the Research
Transmission of Aortic Stenosis Murmur to Carotid Arteries
- The murmur of aortic stenosis can transmit to the carotid arteries, as evidenced by studies that have investigated the relationship between aortic valve murmurs and carotid bruits 1, 2, 3.
- A study published in the American Heart Journal found that aortic stenosis usually presents as a murmur maximal in the aortic area, which is associated with a carotid bruit 1.
- However, another study published in Chest found that aortic systolic murmurs are less frequently transmitted to the carotid and subclavian arteries, where they are usually considerably attenuated 2.
- Phonoangiography has been shown to be capable of accurate differentiation of radiated murmurs from intrinsic carotid bruits and of quantitation of the latter even in the presence of radiated sounds 3.
Characteristics of Transmitted Murmur
- The transmitted murmur to the carotid arteries can be characterized by a bisferious pulse contour, which is a pattern of two systolic peaks, and diastolic reversal of flow direction 4.
- A study published in the AJR American Journal of Roentgenology found that the bisferious pattern was demonstrated in 50% of patients with aortic regurgitation or combined aortic regurgitation and aortic stenosis, and that this pattern is reversible after aortic valve replacement 4.
- Clinically, patients with moderate or severe aortic stenosis have a pulsus parvus et tardus of the carotid artery more often than patients with only slight or no evidence of aortic stenosis, and the murmur radiates more often to the carotid vessels 5.