Cinefluoroscopy for assessment of mechanical heart valves with suspected dysfunction

Background: Mechanical heart valves (MHVs) are preferred prosthesis types
in many, especially younger patients who need surgical valve replacement.
Although echocardiography is most frequently performed for prosthesis
assessment during follow-up, ultrasound artifacts usually preclude a precise
investigation of prosthesis function. Cinefluoroscopy (CF) is a simple and
effective method to analyze and quantify opening and closing of prosthesis
leaflets but requires careful visualization of the valve using optimal viewing
angles. Here, we investigated the quality of CF studies in clinical routine and
their suitability for quantitative analysis of prosthesis function.
Methods and results: We retrospectively identified 94 patients with 118
cinefluoroscopies performed by 31 different investigators in one tertiary
center from 2012 to 2021. Of 150 MHVs (98% bi-leaflet prostheses), 87
(58%) were aortic, 53 (34%) mitral, 7 (5%) tricuspid, and 5 (3%) pulmonary
valve prostheses, respectively. CF studies were categorized by their suitability
to quantitatively assess opening and closing angles. Visualization of valve
function was “sufficient” in 23%, “suboptimal” in 46%, and “unsuitable” in 31%
of the cases.
Conclusion: In clinical routine, only one-fourth of CF studies allow for a
complete assessment of leaflet motion of MHVs. Although this may be in part
due to the varying experience of operators, the high number of unsuitable
studies suggests that optimal viewing angles may not be achievable in all
patients. Further research is required to investigate standard viewing angles
and anatomy after MHV implantation to improve the quality of CF studies and
reduce radiation exposure of patients and operators.