engleski

Beta Stiffness Index in the common Carotid Artery Measured by Three-dimensional Ultrasound

Beta stiffness index is the most common marker for assessment of subclinical atherosclerosis. The aim of this investigation was to explore three-dimensional ultrasound for luminal and midwall circumferential arterial strain (CAS) evaluation and for luminal and midwall beta stiffness index (beta index) evaluation. The investigation was conducted on 10 healthy volunteers. Measurements were performed on Aloka 5500-SSD Prosound ultrasound platform in B and M modes on common carotid artery (CCA) and compared with those obtained with three-dimensional TomTec Imaging software freehandedly over 10 seconds. No ECG trigger was used. Beta indexes were computed. Nonparametric statistics for two related samples was used for evaluation. There were 9 women and 1 man, aged 39, 3+/-9, 2 yrs. There was 1 borderline hypertensive and 4 subjects were active smokers. Average blood pressure values were 113+/-11, 83 over 71+/-8, 43 mmHg and pulse pressure was 42+/-6, 32 mmHg. Average heart rate was 68, 05 +/-6, 85 beats per minute. Average respiration rate was 8+/-2, 1 inspirations per minute. Average body-mass index was 23, 85+/-5, 83 kg/m2. Average IMT was 0, 42+/-0, 06 mm. Luminal CAS was 0, 12+/-0, 03 and midwall CAS was 0, 10+/-0, 04 ; luminal beta index was 4, 43+/-1, 24 and midwall beta was 5, 34+/-2, 12. Using three-dimensional ultrasound luminal CAS was 0, 10+/-0, 05 and midwall CAS was 0, 08+/-0, 05 ; luminal beta index was 6, 39+/-3, 66 and midwall beta was 7, 53+/-3, 84. Statistically, the comparison between conventional and three-dimensional ultrasound corroborated consistency in the left CCA (p>0, 05). Three-dimensional ultrasound was thus far used for exploration of overt carotid disease offering the potential to provide better resolution than conventional ultrasound regarding plaque progression or plaque ulceration. Additionally, three-dimensional arterial wall analysis was performed only in biotechnical studies in place of modeling studies. The advantage of such analysis in vivo might be greater measurement accuracy. The disadvantage could arise from possible motion artifacts caused by hand movement or respiration. The amount of vascular motion present on postprocessed three-dimensional images best fitted that of heart rate. We found this examination to be plausible and will continue with research. This investigation proved that three-dimensional ultrasound could be used for evaluation of CAS and beta index on CCA, especially when evaluating left CCA. Proposed use of three-dimensional ultrasound might provide an answer to the question whether arterial stiffness is equally circumferentially distributed around the examined carotid wall segment and whether it changes in respect to closeness to the carotid bifurcation.

three-dimensional ultrasound; beta stiffness index

ISBN 978-3-8055-8037-3