Early Doppler-echocardiography evaluation of 597 prosthetic aortic valves

Effective valve opening area in the detection of dysfunctional aortic valve prostheses: a differentiated statistical analysis of this parameter including the introduction of minimal expected normal values as borderline to dysfunctional stenotic prostheses

BACKGROUND

Dysfunction of heart valve prostheses (VP) is a life-threatening complication and the diagnosis remains difficult. The motivation for this study was to improve the detection of dysfunctional VP by optimizing application of the prosthetic effective orifice area (VA). For this reason the minimal expected normal VA (VA(expected)) was introduced.

METHODS

We investigated echocardiographically 1,369 normally functioning aortic valve prostheses (AVP). Mean VA, transprosthetic peak (PPG) and mean pressure gradients (MPG) were evaluated to gain reference values depending on prosthetic size and construction principle. Mean VA(expected) was calculated by applying a simple formula that was developed empirically using statistical analyses. The results were compared with those of 65 dysfunctional AVPs.

RESULTS

VA(expected) can be applied as a threshold between normal and dysfunctional stenotic AVP and showed a correct estimation in 87% of all normally functioning and 100% of dysfunctional stenotic VPs. The sensitivity for all prosthetic sizes is 1.0, independently of the constructional principle of the VP. Specificity ranged between 0.8 and 1.0, dependent on VP size. The formula representing VA(expected) is simple and can be executed easily.

CONCLUSION

As nearly independent of stroke volume and in consideration of VA(expected), VA seems to have become one of the preferable parameters for detecting pathological stenotic AVPs echocardiographically. The additional application of PPG/MPG and other parameters permits prostheses with relevant isolated regurgitation and patient-prosthesis-mismatch to be distinguished.

Early Doppler-echocardiography evaluation of Carpentier-Edwards Standard and Carpentier-Edwards Magna aortic prosthetic valve: comparison of hemodynamic performance

OBJECTIVES

This study was designed to describe Doppler-echocardiography values of Carpentier-Edwards Perimount Standard (CEPS) and Carpentier-Edwards Perimount Magna (CEPM) aortic prosthetic valves, evaluated by a single, experienced echo-laboratory, early in the postoperative phase.

METHODS

Three-hundred-seventy-seven consecutive patients, who had had a CEPS or a CEPM implanted in our Hospital due to aortic stenosis and/or insufficiency, underwent baseline Doppler echocardiography evaluation within 7 days after surgery. Hemodynamic performances of CEPS and CEPM were accurately described, evaluating flow-dependent (transprosthetic velocities and gradients) and flow-independent (effective orifice area, indexed effective orifice area and Doppler velocity index) Doppler-echocardiography parameters.

RESULTS

Out of the 377 patients 48.8% were men (n = 184), mean age was 74.63 ± 6.77 years, mean BSA was 1.78 ± 0.18 m2, mean ejection fraction was 57.78 ± 8%. Two-hundred and sixty two CEPS and 115 CEPM were implanted. Comparing size-by-size CEPS with CEPM, both prostheses showed a good hemodynamic profile, with fairly similar values of pressure gradients (PGmax and mean, in mmHg, = 37,18 ± 11.57 and 20.81 ± 7.44 in CEPS n°19 compared to 32,47 ± 7,76 and 17,67 ± 4.63 in CEPM n°19 and progressively lower in higher sized prostheses, having PGmax and mean 15 ± 3,16 and 9.15 ± 1,29 in CEPS n°29 compared to 15,67 ± 1,53 and 9 ± 1 in CEPM n°29) and EOAi (being 0,65 ± 0,33 cm²/m² in CEPS n°19 compared to 0,77 ± 0,29 cm²/m² in CEPM n°19 and progressively higher in higher sized prostheses, being 1,28 ± 0,59 cm²/m² in CEPS n°29 compared to 1,07 ± 0,18 cm²/m² in CEPM n°29), the latter resulting, however, basically less flow obstructive.

CONCLUSIONS

Our data confirm the good hemodynamic performance of both aortic bioprostheses and the more favourable hemodynamic profile of CEPM compared to CEPS, pointing out the need to perform routinely an accurate baseline Doppler-echocardiography evaluation early after surgery to allow an adequate interpretation of data at follow-up.