Flow acceleration time and ratio of acceleration time to ejection time for prosthetic aortic valve function

Area of Science:

• Cardiovascular Medicine
• Echocardiography
• Prosthetic Valve Dysfunction

Background:

• Diagnosing prosthetic aortic valve (PAV) stenosis, particularly in mechanical valves, presents clinical challenges.
• Accurate diagnosis of PAV stenosis is crucial for patient management and clinical outcomes.

Purpose of the Study:

• To evaluate ejection dynamics, specifically acceleration time (AT) and AT/ET ratio, for differentiating PAV stenosis.
• To compare these parameters against controls and prosthesis-patient mismatch (PPM).

Main Methods:

• Doppler echocardiography was performed on 88 patients with PAV (mechanical and bioprosthetic).
• Quantitative Doppler parameters included ejection dynamics (AT, ET, AT/ET) and conventional PAV parameters.
• Patients were categorized into PAV stenosis, PPM, and control groups.

Main Results:

• PAV stenosis showed significantly lower effective orifice area (EOA) and higher gradients than controls and PPM.
• Ejection dynamics (AT and AT/ET) were significantly longer in stenotic valves compared to PPM and controls.
• AT and AT/ET demonstrated high diagnostic accuracy (AUC 0.92 and 0.88, respectively) for identifying PAV stenosis.

Conclusions:

• Ejection dynamics, particularly AT and AT/ET, are reliable and angle-independent parameters for assessing PAV function.
• These parameters effectively aid in the identification of prosthetic aortic valve stenosis.
• The findings support the use of ejection dynamics in routine clinical evaluation of PAVs.