Right ventricular free wall strain predicts quality of life in repaired tetralogy of Fallot
© Lu et al; licensee BioMed Central Ltd. 2013
Published: 30 January 2013
After repair of tetralogy of Fallot (rTOF), left (LVEF) and right (RVEF) ventricular ejection fraction are important markers of clinical status and outcome, but may not improve after pulmonary valve replacement. Strain is a sensitive marker of ventricular dysfunction, but the potential relation to quality of life in this population has not been evaluated.
Fifty-nine patients with rTOF (median age 28 years, range 15-69) underwent cardiovascular magnetic resonance (CMR) from 2008-2009 and completed the Short Form 36 (a validated quality of life assessment). A midventricular short-axis slice was analyzed for left ventricular global circumferential strain (LVGCS) with feature tracking software (TomTec, Unterschleissheim, Germany). A four-chamber slice was analyzed for left ventricular longitudinal strain (LVGLS), and right ventricular longitudinal strain (RVLS), using the three segments of the right ventricular free wall. A subset of 30 patients was re-analyzed for intraobserver and interobserver variability. The physical component summary (PCS) and subscales of physical functioning (PF), role-physical (RP) and general health (GH) were chosen for analysis, and age-adjusted z-score ≤-1 was considered a clinically significant decreased quality of life.
Odds ratios of age-adjusted z-score ≤-1 with strain value below the median. Data presented as odds ratio (95% confidence interval).
1.7 (0.5-6.1) p= 0.39
2.8 (0.8-12) p= 0.13
2.7 (0.6-14) p= 0.19
1.7 (0.5-5.5) p= 0.40
1.7 (0.5-6.1) p= 0.39
1.2 (0.3-4.5) p= 0.76
0.6 (0.1-2.6) p= 0.51
1.2 (0.4-3.8) p= 0.78
2.1 (0.6-7.3) p= 0.12
5.4 (1.4-27) p= 0.01
3.4 (0.8-18) p= 0.10
3.5 (1.1-13) p= 0.04
Although RVLS reflects right ventricular sinus function and not necessarily overall RVEF, it appears to have discriminative ability in this population for decreased quality of life, and may yield incremental prognostic value beyond global RVEF assessment. However, clinical use may be limited by reproducibility. Further study is needed to evaluate techniques to limit variability, and to evaluate longitudinal changes in this population.
The authors have nothing to disclose.
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