Abstract 841 Impact of pressure recovery on the assessment of pulmonary homograft function using Doppler ultrasound

Abstract:

Background Relevant pressure (PR) recovery has been shown to increase functional stenotic aortic valve orifice area and reduce left ventricular load. However, little is known about the relevance of PR in the pulmonary artery.

Objectives:
The study examined the impact of PR using 2D-echocardiography in the pulmonary artery distal to the degenerated homograft in patients after Ross surgery.

Methods 92 patients with pulmonary homograft were investigated by Doppler echocardiography (mean time interval after surgery 31±26 months). PR was measured as a function of pulmonary artery diameter as determined by CT angiography. Homograft orifice area, valve resistance and transvalvular stroke work were calculated with and without consideration of PR.

Results:
PR decreased as the pulmonary artery diameter increased. PR was 41.5+/-7.1% of the Doppler-derived pressure gradient (Pmax), which resulted in a markedly increased homograft orifice area (energy loss coefficient index (ELCOI) vs. effective orifice area index (EOAI), 1.3+/- 0.4cm²/m² vs. 0.9+/-0.4cm²/m², p <0.001), and caused significantly less calculated homograft resistance and transvalvular stroke work. The correlations to the latter parameters were significantly better and 11 of 18 patients (61%) in the group with severe homograft stenosis could be reclassified as moderate stenosis when PR was calculated.

Conclusion:
Our results showed that the uncorrected Doppler measurements overestimated the degree of homograft stenosis and thus the right ventricular load, when a significant pressure recovery was determined in the pulmonary artery. As a result, Doppler measurements that ignore pressure recovery can misclassify homograft stenosis and may lead to premature surgery.

Clin Res Cardiol (2022). https://doi.org/10.1007/s00392-022-02002-5
Impact of pressure recovery on the assessment of pulmonary homograft function using Doppler ultrasound
C. Marquetand¹, J.-C. Reil¹, C. Busch-Tilge², A. Aboud², S. Ensminger², E. Charitos³, G.-H. Reil⁴, U. Stierle⁵
¹Medizinische Klinik II / Kardiologie, Angiologie, Intensivmedizin, Universitätsklinikum Schleswig-Holstein, Lübeck; ²Klinik für Herz- und thorakale Gefäßchirurgie, Universitätsklinikum Schleswig-Holstein, Lübeck; ³Abteilung für Herzchirurgie, Kerckhoff Klinik GmbH, Bad Nauheim; ⁴Klinik für Kardiologie, Klinikum Oldenburg AöR, Oldenburg; ⁵Praxis, Lübeck;
Abstract: Background Relevant pressure (PR) recovery has been shown to increase functional stenotic aortic valve orifice area and reduce left ventricular load. However, little is known about the relevance of PR in the pulmonary artery. Objectives: The study examined the impact of PR using 2D-echocardiography in the pulmonary artery distal to the degenerated homograft in patients after Ross surgery. Methods 92 patients with pulmonary homograft were investigated by Doppler echocardiography (mean time interval after surgery 31±26 months). PR was measured as a function of pulmonary artery diameter as determined by CT angiography. Homograft orifice area, valve resistance and transvalvular stroke work were calculated with and without consideration of PR. Results: PR decreased as the pulmonary artery diameter increased. PR was 41.5+/-7.1% of the Doppler-derived pressure gradient (Pmax), which resulted in a markedly increased homograft orifice area (energy loss coefficient index (ELCOI) vs. effective orifice area index (EOAI), 1.3+/- 0.4cm²/m² vs. 0.9+/-0.4cm²/m², p <0.001), and caused significantly less calculated homograft resistance and transvalvular stroke work. The correlations to the latter parameters were significantly better and 11 of 18 patients (61%) in the group with severe homograft stenosis could be reclassified as moderate stenosis when PR was calculated. Conclusion: Our results showed that the uncorrected Doppler measurements overestimated the degree of homograft stenosis and thus the right ventricular load, when a significant pressure recovery was determined in the pulmonary artery. As a result, Doppler measurements that ignore pressure recovery can misclassify homograft stenosis and may lead to premature surgery.
https://dgk.org/kongress_programme/jt2022/aP1868.html