Author + information
- Received June 8, 2011
- Revision received August 2, 2011
- Accepted August 18, 2011
- Published online November 1, 2011.
- Sagit Ben Zekry, MD⁎,
- Robert M. Saad, MD⁎,
- Mehmet Özkan, MD†,
- Maie S. Al Shahid, MD‡,
- Mauro Pepi, MD§,
- Manuela Muratori, MD§,
- Jiaqiong Xu, PhD∥,
- Stephen H. Little, MD⁎ and
- William A. Zoghbi, MD⁎,⁎ ()
- ↵⁎Reprint requests and correspondence:
Dr. William A. Zoghbi, Cardiovascular Imaging Institute, The Methodist DeBakey Heart and Vascular Center, 6550 Fannin Street, SM 677, Houston, Texas 77030
Objectives We sought to evaluate whether ejection dynamics, particularly acceleration time (AT) and the ratio of AT to ejection time (ET), can differentiate prosthetic aortic valve (PAV) stenosis from controls and prosthesis–patient mismatch (PPM).
Background Diagnosing PAV stenosis, especially in mechanical valves, may be challenging and has significant clinical implications.
Methods Doppler echocardiography was quantitated in 88 patients with PAV (44 mechanical and 44 bioprosthetic; age 63 ± 16 years; valve size range 18 to 25 mm) of whom 22 patients had documented PAV stenosis, 22 had PPM, and 44 served as controls. Quantitative Doppler parameters included ejection dynamics (AT, ET, and AT/ET) and conventional PAV parameters.
Results Patients with PAV stenosis had significantly lower effective orifice area (EOA) values and higher gradients compared with controls and PPM. Flow ejection parameters (AT and AT/ET) were significantly longer in the stenotic valves compared with PPM and controls (respective values for AT: 120 ± 24 ms, 89 ± 16 ms, and 71 ± 15 ms; for AT/ET: 0.4, 0.32, and 0.3, p ≤ 0.001). Patients with PPM had gradients and ejection dynamics that were intermediate between normal and stenotic valves. Receiver-operator characteristic (ROC) curve analysis showed that AT and AT/ET discriminated PAV stenosis from PPM and controls (area under ROC curve = 0.92 and 0.88, respectively). Combining AT with the conventional Doppler velocity index gave the highest area under the curve of 0.98 but was not statistically different from that of AT alone (p = 0.12). A cutoff of AT = 100 ms had a sensitivity and specificity of 86% for identifying PAV stenosis; for an AT/ET = 0.37, the sensitivity and specificity were 96% and 82%, respectively. Analysis by valve type (mechanical and biological) revealed similar results; however, biological valves had slightly higher areas under the curve for all systolic time intervals.
Conclusions Ejection dynamics through PAV, particularly AT and AT/ET, are reliable angle-independent parameters that can help evaluate valve function and identify PAV stenosis.
Dr. Little has received research support from St. Jude Medical and Siemens Medical Imaging. All other authors have reported that they have no relationships relevant to the contents of this paper to disclose. Jeroen J. Bax, MD, PhD, served as Guest Editor for this paper.
Presented in part at the Annual Scientific Sessions of the American Heart Association, November 2008, New Orleans, Louisiana.
- Received June 8, 2011.
- Revision received August 2, 2011.
- Accepted August 18, 2011.
- American College of Cardiology Foundation