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

Abstract

BackgroundAccurate evaluation of the tricuspid regurgitant (TR) spectral Doppler signal is important during transthoracic echocardiographic (TTE) evaluation for pulmonary hypertension (PHT). Contrast enhancement improves Doppler backscatter. However, its incremental benefit with contemporary scanners is less well established. The aim of this study was to assess whether the TR spectral Doppler signal using contemporary scanners was improved using a second generation contrast agent, Definity® (CE), compared to unenhanced TTE (UE).MethodsAnalysis of patients who underwent UE then CE TR interrogation was performed. TR signal was evaluated by an experienced reader and graded 1 (clear-high level of confidence of interpretation and complete spectral Doppler envelope), 2 (suboptimal with medium-low level of confidence of interpretation and incomplete envelope), 3 (poor-absent and no measurable spectral Doppler signal). Maximal TR velocity (TRV) was defined as peak velocity that could be clearly identified. An inexperienced sonographer read 30 randomly selected studies.Results176 TTE were performed in 173 patients (mean age 57 ± 14.8 years). Wilcoxon signed rank test demonstrated significant improvement (p < 0.0001) in TR spectral Doppler signal quality with CE TTE. Mean score CE TTE vs. TTE = 2.32 ± 0.85 vs. 2.56 ± 0.75 respectively (p < 0.0001). Mean maximal TRV CE TTE vs. UE TTE = 2.61 ± 0.44 m/s vs. 2.54 ± 0.49 m/s respectively (p < 0.0001). The inexperienced reader had a greater improvement in scoring CE TTE signals vs. UE TTE (p < 0.0001).ConclusionIn the era of contemporary scanners, CE improved the ability to detect and measure TRV, except in those with clear unenhanced TR spectral Doppler signals or greater than mild tricuspid regurgitation.

Echocardiographic assessment of pulmonary hypertension: a guideline protocol from the British Society of Echocardiography

“…1 ). In patients with a trivial TR jet or sub optimal continuous wave Doppler spectrum, injection of intravenous agitated saline can be considered to improve the Doppler signal allowing measurement of peak TR velocity ( 37 ) ( Fig. 3 ).…”

Echocardiography to Screen for Pulmonary Hypertension in CKD

“… 29 Although indices of right ventricular size and function strongly associated with PH in our study, severe right ventricular dysfunction may paradoxically lower the pulmonary artery pressure and evade detection of PH in select patients. 30 Although TRV is difficult to measure in certain cases, select maneuvers, such as the use of contrast or agitated saline, may improve the ability to measure TRV 31 ; we were not able to standardize or capture the use of these techniques in this study. We also could not control for reversible volume overload, especially regarding the timing of the echocardiogram or catheterization relative to hemodialysis in persons with end-stage kidney disease.…”

A better method to evaluate the reliability of echocardiography for assessment of pulmonary hypertension: comparison of tricuspid regurgitant spectrum quality grading and tricuspid valve regurgitation degree

“…Therefore, a large proportion of low spectra quality (TR-SQG I 20.00% and TR-SQG II 32.31%) in mild TR could explain the inaccurate assessment and the poor agreement. This problem can be alleviated in part by using contrast bubbles in the right side of the heart or injecting of intravenous agitated saline ( 31 ). In addition, a study by Jeon et al ( 32 ) demonstrated that the correlations were further improved and the best limits of agreement were obtained between echocardiography and RHC measurements using a 10% air, 10% blood, and 80% saline mixture.…”