Feasibility of resting transthoracic LAD color Doppler targeting and coronary flow velocity sampling in the PENSIAMOCI-PRIMA screening cohort
D Donelli, N Gaibazzi, A Moreo, F RigoAbstract
Background
Resting transthoracic coronary Doppler could enable coronary risk phenotyping, but LAD color Doppler visualization for targeting and feasibility of LAD flow velocity sampling is not well established.
Methods
In an asymptomatic primary-prevention cohort undergoing cardiovascular ultrasound screening, LAD color Doppler visibility was graded as 0 (not visible), 1 (partially visible, sufficient to guide PW Doppler sampling), or 2 (fully visible, unequivocal). The primary feasibility endpoint was PW feasibility (visibility ≥1). Secondary endpoints were full visibility (visibility=2) and determinants of non-feasibility and full vs partial visibility using logistic regression; overall visibility grade was also evaluated with ordinal regression. Examinations were performed using ultrasound systems equipped with a standard single-crystal phased-array cardiac transducer.
Results
Among 1,100 examinations, LAD visibility was 0 in 5 (0.46%), 1 in 1,020 (92.7%), and 2 in 75 (6.82%). Color-targeted PW Doppler sampling was feasible in 1,095/1,100 (99.55%; 95% CI 98.94–99.85), whereas full LAD visualization was achieved in 75/1,100 (6.82%; 95% CI 5.40–8.47). Non-feasibility was extremely rare (n=5); in univariable bias-reduced logistic regression, abdominal circumference showed the strongest association with non-feasibility (OR 1.03 per cm, 95% CI 0.99–1.07; p=0.135). Among feasible examinations (partial vs full), LAD visibility was associated with diabetes, higher sinus heart rate, and larger abdominal circumference, suggesting that visibility grade may reflect both acoustic window and flow-signal/acquisition conditions.
Conclusions
In a primary prevention screening setting, LAD color Doppler visualization is sufficient to guide PW Doppler flow velocity sampling, despite a low rate of unequivocal (“fully visible”) color Doppler delineation. The visibility grade appears to be influenced by both acquisition-related and clinical factors. These findings support the scalability of resting transthoracic coronary Doppler for large-scale screening and coronary risk phenotyping. Importantly, PW Doppler sampling feasibility, rather than unequivocal color Doppler visualization, may represent the most pragmatic endpoint when considering the dissemination of coronary Doppler within screening workflows.