Impact of Echo-Contrast (Definity®) to Enhance Spectral Doppler Tricuspid Regurgitation Signals

Abstract

we prospectively analysed radiation dose and determinants in four cohorts of consecutive patients (n = 525) undergoing CCT at pre-defined time points -post-installation, post console upgrades and post introduction of an iterative image reconstruction algorithm (AIDR3D). The impact of these updates on radiation dose were analysed by BMI subgroups (BMI ≤ 20,20 < BMI ≤ 25,25 < BMI ≤ 30,30 < BMI ≤ 35,35 < BMI). Summary statistics were compared with means or medians (S.D. or interquartile range) as appropriate. Comparisons of radiation dose between cohorts were by independent samples median test. Baseline characteristics (age, sex, BMI) were similar between all cohorts.Results: Progressive reductions in radiation dose were seen across all BMI subgroups. Comparing the first and fourth cohorts there were significant reductions in median radiation dose across all subgroups (p < 0.02). Individuals with a BMI > 35 had reduced median dose-length product from 1142.3 mGy cm (IQR: 915-1759, n = 31) (1st cohort) to 318.4 mGy cm (IQR: 254-515, n = 16) (4th cohort) (p < 0.001). All CCTs were of diagnostic quality.

Contrast microsphere enhancement of the tricuspid regurgitant spectral Doppler signal - Is it still necessary with contemporary scanners?

“…However, all these studies have used a first generation contrast agent such as sonicated albumin or Levovist © (Bayer, Germany). The current evidence base for the utility of a second generation contrast agent in spectral Doppler signal enhancement coupled with contemporary scanners is almost non-existent, limited to just one abstract and a single case report [8] , [36] . Second generation contrast agents backscatter ultrasound at a rate 100 million times that of red blood cells [37] .…”

“…In those patients with sub-optimal or no TR spectral Doppler signals, injection of agitated saline or echocardiographic contrast agents is recommended to enhance the Doppler signal [1] , [3] , [4] , [5] , [7] . However, the evidence base for this recommendation using second generation contrast agents and contemporary scanners is scant [8] . The aim of this study was to evaluate whether administration of a second generation contrast agent, Definity® (Lantheus Medical Imaging, North Billerica, MA, USA) whilst using contemporary scanners, would improve the derivation and measurement of the TR spectral Doppler envelope compared to conventional unenhanced imaging.…”