BACKGROUND AND AIM OF THE STUDY: Discrepancies between Doppler and catheter gradients have been reported for bileaflet aortic valve prostheses. Whether modifications in geometric design of newly developed bileaflet valves lead to a different Doppler-catheter gradient relationship has not been evaluated. Variable results have been reported for tilting-disc prostheses. In addition, the effect of aortic size on the Doppler-catheter gradient relationship remains unclear. METHODS: Various sizes of On-X and Edwards Mira (identical with Sorin Bicarbon) bileaflet valves and Sorin Allcarbon tilting-disc aortic valves (19-25 mm) were studied in a pulsatile flow model. Doppler and catheter gradients were measured simultaneously. Aortic diameters between 1.8 and 4 cm were evaluated. RESULTS: Correlation between Doppler and catheter gradients was excellent (r = 0.98-0.99 for peak and mean gradients), but in bileaflet valves Doppler significantly overestimated the corresponding catheter gradients as reflected by slopes of the regression lines (1.57-1.8). In the range of relevant gradients > or = 10 mmHg, Doppler exceeded catheter gradients by 40 +/- 17% (peak) and 39 +/- 16% (mean) in Mira valves, and by 46 +/- 19% (peak) and 43 +/- 14% (mean) in On-X valves. In the Sorin tilting-disc valve, Doppler accurately reflected catheter gradients (slopes of regression lines 1.05-1.14). The aortic diameter significantly influenced results in only tilting-disc valves, but in absolute terms the effect was clinically less relevant. CONCLUSION: Discrepancies between Doppler and catheter gradients are common to all bileaflet valves, regardless of their specific geometric design, whereas tilting-disc valves must be considered individually. The influence of aortic size on the Doppler-catheter gradient relationship appears clinically to be less relevant in prosthetic valves.
BACKGROUND AND AIM OF THE STUDY: Discrepancies between Doppler and catheter gradients have been reported for bileaflet aortic valve prostheses. Whether modifications in geometric design of newly developed bileaflet valves lead to a different Doppler-catheter gradient relationship has not been evaluated. Variable results have been reported for tilting-disc prostheses. In addition, the effect of aortic size on the Doppler-catheter gradient relationship remains unclear. METHODS: Various sizes of On-X and Edwards Mira (identical with Sorin Bicarbon) bileaflet valves and Sorin Allcarbon tilting-disc aortic valves (19-25 mm) were studied in a pulsatile flow model. Doppler and catheter gradients were measured simultaneously. Aortic diameters between 1.8 and 4 cm were evaluated. RESULTS: Correlation between Doppler and catheter gradients was excellent (r = 0.98-0.99 for peak and mean gradients), but in bileaflet valves Doppler significantly overestimated the corresponding catheter gradients as reflected by slopes of the regression lines (1.57-1.8). In the range of relevant gradients > or = 10 mmHg, Doppler exceeded catheter gradients by 40 +/- 17% (peak) and 39 +/- 16% (mean) in Mira valves, and by 46 +/- 19% (peak) and 43 +/- 14% (mean) in On-X valves. In the Sorin tilting-disc valve, Doppler accurately reflected catheter gradients (slopes of regression lines 1.05-1.14). The aortic diameter significantly influenced results in only tilting-disc valves, but in absolute terms the effect was clinically less relevant. CONCLUSION: Discrepancies between Doppler and catheter gradients are common to all bileaflet valves, regardless of their specific geometric design, whereas tilting-disc valves must be considered individually. The influence of aortic size on the Doppler-catheter gradient relationship appears clinically to be less relevant in prosthetic valves.
Authors: Amr E Abbas; Ramy Mando; Amer Kadri; Houman Khalili; George Hanzel; Francis Shannon; Karim Al-Azizi; Thomas Waggoner; Safwan Kassas; Thomas Pilgrim; Taishi Okuno; Alexander Camacho; Alexandra Selberg; Sammy Elmariah; Anthony Bavry; Julien Ternacle; Jared Christensen; Neil Gheewala; Philippe Pibarot; Michael Mack Journal: J Am Heart Assoc Date: 2021-09-29 Impact factor: 5.501