Comparison of magnetic resonance imaging and transthoracic echocardiography for the identification of LV mass and volume regression indices 6 months after mitral valve repair.

BACKGROUND: Magnetic Resonance Imaging (MRI) and transthoracic echocardiography have been shown to be noninvasive highly sensitive diagnostic tools to identify changes in LV mass and volume. We therefore investigated the effects of mitral valve repair (MVR) on LV function parameters including ejection fraction (EF; %), indices of LV mass (LVMI; g/m2) and volume (LVEDVI, LVESVI; mL/m2) as detected by MRI and echocardiography. METHODS: Eight consecutive patients (mean age 53.3 +/- 10.0 years) with severe mitral regurgitation (MR; grade III-IV), normal LV function and sinus rhythm were included in this prospective study. Cine MRI and transthoracic M-mode echocardiography were performed pre-operatively, as well as 6 months post-op, to identify changes in EF and in LV mass and volume. Data are given as mean +/- standard deviation. RESULTS: Post-op MR was grade 0-I in all patients. Early mortality and late mortality was 0%. EF by either method did not change significantly within the follow-up period. A significant improvement of indices of LV mass and volume was detected by Cine MRI and echocardiography within 6 months following surgery (LVMIMRI: pre-op: 76.3 +/- 20.1 vs. post-op: 66.5 +/- 14.3, p < 0.05; LVMIEcho: pre-op: 184.2 +/- 38.1 vs. post-op: 136.5 +/- 28.4, p < 0.05. LVEDVIMRI: pre-op: 119.3 +/- 26.0 vs. post-op: 75.4 +/- 13.1, p < 0.05; LVEDVIEcho: pre-op: 97.4 +/- 28.8 vs. post-op: 69.2 +/- 13.1, p < 0.05. LVESVIMRI: pre-op: 44.6 +/- 12.0 vs. post-op: 32.5 +/- 9.5, p < 0.05; LVESVIEcho: pre-op: 29.3 +/- 8.3 vs. post-op: 21.8 +/- 4.6, p < 0.05). CONCLUSIONS: MRI and echocardiography show a significant reduction of LV volume and mass 6 months after MVR. The data show that for routine follow-up transthoracic M-mode echocardiography provides reliable information for the identification of LV mass and volume regression in patients after MVR.

Hemodynamic performance and incidence of patient-prosthesis mismatch of the complete supraannular perimount magna bioprosthesis in the aortic position.

BACKGROUND: Complete supraannular placement and smaller stent design allow the implantation of a Perimount Magna bioprosthesis with a larger inner diameter than that of a standard Perimount. This study compares the hemodynamic performance and the incidence of patient-prosthesis mismatch (PPM) of both prostheses. METHODS: 128 patients underwent aortic valve replacement, receiving either a Magna (n = 57) or a standard (n = 71) prosthesis. Inner aortic annulus diameter was measured intraoperatively by a hegar dilator to match echocardiographically obtained results to the annulus diameter instead of matching them to labelled valve size. RESULTS: The Magna was significantly superior with respect to mean pressure gradient and effective orifice area in patients with an annulus diameter of 22-23 mm. In patients with an annulus diameter < 22 mm or > 23 mm, there was a non-significant trend towards superior hemodynamics in the Magna group. Severe PPM (effective orifice area index < or = 0.65 cm (2)/m (2)) was present in 11.1% (Magna) vs. 42.1% (Standard) of patients with an annulus diameter < 22 mm; in 0% (Magna) vs. 13.8% (Standard) with an annulus diameter of 22-23 mm; no PPM was seen in patients with annulus diameter > 23 mm in both groups. CONCLUSIONS: The Perimount Magna had a significantly reduced incidence of patient-prosthesis mismatch and superior hemodynamics compared to the standard Perimount.