Factors associated with right ventricular dilatation and dysfunction in patients with chronic pulmonary regurgitation after repair of tetralogy of Fallot: analysis of magnetic resonance imaging data from 218 patients.

The aim of the present study was to identify the factors associated with right ventricular (RV) dilatation and dysfunction in patients with chronic pulmonary regurgitation (PR) after repair of tetralogy of Fallot. From April 2002 to June 2013, 218 patients with repaired tetralogy of Fallot underwent magnetic resonance imaging; 165 (76%) underwent transannular repair and 36 (17%) underwent nontransannular repair. Linear regression analyses were used to identify the predictors for RV end-diastolic volume index (EDVI), end-systolic volume index (ESVI), and ejection fraction. On univariable analysis, male sex, ventricular septal defect (VSD) closure through the right ventricle, larger pulmonary artery index, and greater PR fraction were associated with greater RV volume indexes. Multivariable analyses identified male sex (β = 17.55, P < .001 for RV EDVI; β = 14.08, P = .001 for RV ESVI), VSD closure through RV (β = 8.49, P = .048 for RV ESVI), longer interval since repair (β = 1.29, P = .014 for RV EDVI), and greater PR fraction (β = 1.92, P < .001 for RV EDVI; β = 1.38, P < .001 for RV ESVI) as independent predictors for greater RV volume indexes. On univariable analysis, male sex, VSD closure through the right ventricle, and greater PR fraction were associated with a lower RV ejection fraction. Multivariable analysis identified male sex (β = -3.10, P = .018), VSD closure through the right ventricle (β = -3.05, P = .020), and greater PR fraction (β = -0.27, P < .001) as independent predictors for a lower RV ejection fraction. Male sex, VSD closure through the right ventricle, longer interval since repair, and greater PR fraction were independent predictors of RV dilatation after tetralogy of Fallot repair. Male sex, VSD closure through the right ventricle, and greater PR fraction were also independent predictors of RV dysfunction.

Lee C ，Lee CH ，Kwak JG ，Kim SH ，Shim WS ，Lee SY ，Jang SI ，Park SJ ，Kim YM ... -  《-》

Impact of pressure load caused by right ventricular outflow tract obstruction on right ventricular volume overload in patients with repaired tetralogy of Fallot.

In correction of tetralogy of Fallot (TOF), surgical strategies to minimize right ventricular outflow tract (RVOT) enlargement have recently been preferred. However, we may be confronted with residual pulmonary stenosis (PS) combined with pulmonary regurgitation (PR), and how the pressure load affects these patients is not evident. We compared 51 patients with PR and significant PS (PR with PS group) with 87 patients with PR without significant PS (PR group) using echocardiography and cardiac magnetic imaging. We evaluated the differences in parameters derived by magnetic resonance imaging between the 2 groups and the influence of the pressure load on right ventricular (RV) volume and function. Although the PR fraction was similar between the 2 groups, the PR with PS group showed significantly smaller RV end-diastolic volume (136.7 ± 26.5 mL/m(2) vs 151.2 ± 34.7 mL/m(2); P = .01), RV end-systolic volume (68.1 ± 23.7 mL/m(2) vs 80.2 ± 27.5 mL/m(2); P = .01), and slightly better RV ejection fraction (51.1% ± 9.8% vs 47.6% ± 8.9%; P = .03) than the PR group. For influence of the pressure load, PR fraction (r = -0.18, P = .03), RV end-diastolic volume (r = -0.25, P = .003), and RV end-systolic volume (r = -0.24, P = .005) were decreased as peak pressure gradient of PS was higher. Linear regression analysis revealed that both PR fraction and peak pressure gradient of PS were independent predictors for RV volume. Our study demonstrated that the RV pressure load prevented RV dilatation from chronic PR without systolic dysfunction. It is suggested that a proper relief of RVOT obstruction with acceptable residual stenosis is more advantageous than aggressive RVOT enlargement in the long-term outcome of repaired TOF.

Yoo BW ，Kim JO ，Kim YJ ，Choi JY ，Park HK ，Park YH ，Sul JH ... -  《-》

Power loss and right ventricular efficiency in patients after tetralogy of Fallot repair with pulmonary insufficiency: clinical implications.

To quantify right ventricular output power and efficiency and correlate these to ventricular function in patients with repaired tetralogy of Fallot. This might aid in determining the optimal timing for pulmonary valve replacement. We reviewed the cardiac catheterization and magnetic resonance imaging data of 13 patients with tetralogy of Fallot (age, 22 ± 17 years). Using pressure and flow measurements in the main pulmonary artery, cardiac output and regurgitation fraction, right ventricular (RV) power output, loss, and efficiency were calculated. The RV function was evaluated using cardiac magnetic resonance imaging. The RV systolic power was 1.08 ± 0.62 W, with 20.3% ± 8.6% power loss owing to 41% ± 14% pulmonary regurgitation (efficiency, 79.7% ± 8.6%; 0.84 ± 0.73 W), resulting in a net cardiac output of 4.24 ± 1.82 L/min. Power loss correlated significantly with the indexed RV end-diastolic and end-systolic volume (R = 0.78, P = .002 and R = 0.69, P = .009, respectively). The normalized RV power output had a significant negative correlation with RV end-diastolic and end-systolic volumes (both R = -0.87, P = .002 and R = -0.68, P = .023, respectively). A rapid decrease occurred in the RV power capacity with an increasing RV volume, with the curve flattening out at an indexed RV end-diastolic and end-systolic volume threshold of 139 mL/m(2) and 75 mL/m(2), respectively. Significant power loss is present in patients with repaired tetralogy of Fallot and pulmonary regurgitation. A rapid decrease in efficiency occurs with increasing RV volume, suggesting that pulmonary valve replacement should be done before the critical value of 139 mL/m(2) and 75 mL/m(2) for the RV end-diastolic and end-systolic volume, respectively, to preserve RV function.

Fogel MA ，Sundareswaran KS ，de Zelicourt D ，Dasi LP ，Pawlowski T ，Rome J ，Yoganathan AP ... -  《-》

Relative Impact of Right Ventricular Electromechanical Dyssynchrony Versus Pulmonary Regurgitation on Right Ventricular Dysfunction and Exercise Intolerance in Patients After Repair of Tetralogy of Fallot.

Lumens J ，Fan CS ，Walmsley J ，Yim D ，Manlhiot C ，Dragulescu A ，Grosse-Wortmann L ，Mertens L ，Prinzen FW ，Delhaas T ，Friedberg MK ... -  《Journal of the American Heart Association》

Does limited right ventriculotomy prevent right ventricular dilatation and dysfunction in patients who undergo transannular repair of tetralogy of Fallot? Matched comparison of magnetic resonance imaging parameters with conventional right ventriculotomy l

The objective of this study was to test the hypothesis that limited (<1 cm) right ventriculotomy (RV-tomy) in the setting of transannular tetralogy of Fallot (TOF) repair might result in less right ventricular (RV) dilatation and dysfunction compared with conventional RV-tomy. Between June 2002 and April 2012, 113 patients with transannular repair of TOF underwent magnetic resonance imaging (MRI). Patients were divided into a limited RV-tomy group (n = 39) and a conventional RV-tomy group (n = 74). Thirty-nine patients from each group were matched for comparison using propensity scores. The MRI parameters of the 2 groups were compared. The interval between TOF repair and MRI examination was shorter in the limited RV-tomy group (limited, 12.7 ± 3.8 years; conventional, 17.2 ± 4.7 years; P < .001). Indexed RV volumes were similar between the groups (RV end-diastolic volume index: 149 ± 31 mL/m(2) vs 152 ± 42 mL/m(2); P = .704. RV end-systolic volume index: 70 ± 24 mL/m(2) vs 77 ± 38 mL/m(2); P = .313). There was no difference in the RV ejection fraction between the groups (54% ± 9% vs 51% ± 9%; P = .160). Propensity score-matched comparison also revealed no differences in RV volume and function. No long-term benefits of limited RV-tomy were demonstrated compared with conventional RV-tomy in patients who underwent transannular TOF repair, at least in terms of RV volume and function. Further studies are necessary to define the role of limited RV-tomy in patients who undergo transannular TOF repair.

Lee C ，Lee CH ，Kwak JG ，Kim SH ，Shim WS ，Lee SY ，Baek JS ，Jang SI ，Kim YM ... -  《-》