The relation of right ventricular outflow tract measurements with in-hospital clinical outcomes after tricuspid valve surgery

Right ventricular (RV) function is a determining factor for clinical outcomes in patients undergoing tricuspid valve surgery (TVS). Our aim was to investigate the importance of the function of the right ventricular outflow tract (RVOT), which is an important anatomical region of the RV, in patients underwent TVS. 104 patients who underwent TVS were analyzed retrospectively. Patients with previous cardiac surgery, congenital heart disease, or heart failure were excluded. The parasternal short-axis view at the level of the aortic root was used to measure RVOT dimensions and RVOT fractional shortening (RVOT-FS). The effect of RVOT diameter and function on major adverse cardiac events (MACE) after TVS was investigated. In our study, MACE, consisting of pacemaker implantation, acute kidney injury, postoperative atrial fibrillation and mortality, was developed at 44 (42.3%) patients.We compared the predictive performances of RVOT end-systolic (RVOTs) diameter, RVOT end-diastolic (RVOTd) diameter, RVOT-FS and RV diameters in prediction of MACE. The model including the RVOTs had higher AUC, R2 and likelihood ratio X2 values (0.775, 0.287 and 25.0, respectively) than RVOTd (0.770, 0.279 and 24.2, respectively) and RVOT-FS (0.750, 0.215 and 18.1, respectively). RVOT diameters showed better performance in predicting MACE than RV diameters. Moreover, there was statistically significant association between RVOTs, RVOTd and MACE (p value were 0.014 and 0.027, respectively), while no association between RVOT-FS and MACE (p value was 0.177). In summary, we determined that the RVOT diameters are important predictors for the in-hospital clinical outcomes of patients who underwent TVS.

Color tissue doppler imaging of tricuspid annular plane systolic and diastolic excursion in children: A comparison of normal, volume-overloaded and pressure overloaded right ventricles

BACKGROUND

Tricuspid annular plane (TAP) systolic excursion (TAPSE) is a reproducible M-mode parameter for the measurement of longitudinal shortening of the right ventricle (RV). To date, all attention has been focused on the systolic excursion of TAP and the diastolic excursion of the annular plane back to the base has been ignored. This study aims to compare the quantitative (excursion, slope, and duration) and qualitative (velocity, acceleration, and indentation) characteristics of TAP systolic and diastolic excursion, using color tissue Doppler imaging, in three groups of children with normal RV (NORV), volume overloaded RV (VORV), and pressure overloaded RV (PORV) and normal pulmonary arterial pressure.

SUBJECTS AND METHODS

A prospective case-control study was performed in three groups of children with normal heart, VORV and PORV. TAPSE and tricuspid annular plane diastolic excursion (TAPDE) were quantitatively and qualitatively analyzed and compared between the three groups. Statistical analysis was performed using IBM SPSS Statistics for Windows.

RESULTS

TAPSE, TAPDE, TAPSE slope, TAPSE slope/TAPDE slope, TAPDE duration and TAPDE duration/RR interval were lower in PORV (TAPSE: PORV: 14.45 ± 4.30, NORV: 20.45 ± 5.46, P = .003, TAPDE:PORV: 14.39 ± 4.61, NORV: 20.28 ± 5.65, P = .004, TAPSE slope:PORV: 4.79 ± 1.40, NORV: 7.15 ± 1.98, P = .001, .001, TAPDE duration:PORV: 201.1 ± 87.9 ms, NORV: 292.1 ± 97.9, P = .006, TAPDE duration/RR interval: PORV: .37 ± .09, NORV: .48 ± .08, P = .0002).

CONCLUSION

Pressure-overload on RV produced more impairment of TAPSE and TAPDE patterns than volume overload. Values of TAPSE and TAPDE in patients with VORV and PORV stay in two ends of the normal spectrum. The harmful impact of pre-tricuspid volume overload seems to be less than the post-tricuspid volume overload.

Assessment of regional and global right ventricular systolic function in children with repaired tetralogy of Fallot

BACKGROUND

Echo assessment of right ventricular function is difficult due to its complex geometry and regional differences in wall motion. In patients with repaired tetralogy of Fallot, cardiac MRI is the gold standard for assessment of right ventricular function. There is scant data regarding the correlation of echo measures of right ventricular function with cardiac MRI right ventricular function in the paediatric population.

METHODS

Echocardiographic measures of regional and global right ventricular function were reviewed in 56 patients with repaired tetralogy of Fallot and 27 patients with structurally normal hearts. These measures were compared to global right ventricular ejection fraction by cardiac MRI.

RESULTS

Despite having the same right ventricular ejection fraction by cardiac MRI as normal controls, patients with repaired tetralogy of Fallot had significantly worse global and regional echocardiographic measures of right ventricular function. Right ventricular fractional area change and fractional shortening of the right ventricular outflow tract correlated best with global right ventricular function by MRI. Incorporation of these measures into a regression model allowed accurate prediction of global right ventricular function by cardiac MRI.

CONCLUSION

Children with repaired tetralogy of Fallot have abnormal regional and global right ventricular function compared to patients with normal hearts. Despite the presence of patch material, the right ventricular outflow tract significantly contributes to global right ventricular function by cardiac MRI. When incorporated into a model that includes regional and global echocardiographic measures of right ventricular function, right ventricular outflow tract fractional shortening helps predict global right ventricular function by MRI.

Impaired Exercise Tolerance in Repaired Tetralogy of Fallot Is Associated With Impaired Biventricular Contractile Reserve: An Exercise-Stress Real-Time Cardiovascular Magnetic Resonance Study

BACKGROUND

Correction of tetralogy of Fallot (cTOF) often results in pulmonary valve pathology and right ventricular (RV) dysfunction. Reduced exercise capacity in cTOF patients cannot be explained by these findings alone. We aimed to explore why cTOF patients exhibit impaired exercise capacity with the aid of a comprehensive cardiopulmonary exercise testing (CPET) and real-time cardiovascular magnetic resonance exercise testing (CMR-ET) protocol.

METHODS

Thirty three cTOF patients and 35 matched healthy controls underwent CPET and CMR-ET in a prospective case-control study. Real-time steady-state free precession cine and phase-contrast sequences were obtained during incremental supine in-scanner cycling at 50, 70, and 90 W. RV and left ventricle (LV) volumes and pulmonary blood flow (Qp) were calculated. Differences of CPET and CMR-ET between cTOF versus controls and correlations between CPET and CMR-ET parameters in cTOF were evaluated statistically for all CMR exercise levels using Mann-Whitney U and Spearman rank-order correlation tests.

RESULTS

CPET capacity was significantly lower in cTOF than in controls. cTOF patients exhibited not only significantly reduced Qp and RV function but also lower LV function on CMR-ET. Higher CPET values in cTOF correlated with higher Qp (Qp 90 W versus carbon dioxide ventilatory equivalent %: R=-0.519, P<0.05), higher LV-end-diastolic volume indexed to body surface area (LV-end-diastolic volume indexed to body surface area at 50 W versus oxygen uptake in % at maximum exercise on CPET R=0.452, P<0.05), and change in LV ejection fraction (EF; LV-EF at 90 W versus Watt %: r=-0.463, P<0.05). No correlation was found with regard to RV-EF. Significant RV-LV interaction was observed during CMR-ET (RV-EF versus LV-EF at 50 W and 70 W: r=0.66, P<0.02 and r=0.52, P<0.05, respectively).

CONCLUSIONS

Impaired exercise capacity in cTOF resulted from a reduction in not only RV, but also LV function. cTOF with good exercise capacity on CPET demonstrated higher LV reserve and pulmonary blood flow during incremental CMR-ET. Apart from RV parameters, CMR-ET-derived LV function could be a valuable tool to stratify cTOF patients for pulmonary valve replacement.

Systolic Function of Right Ventricular Outflow Tract is a Better Predictor to Exercise Performance After Pulmonary Valve Replacement in Tetralogy of Fallot

Debate on the proper timing of pulmonary valve replacement (PVR) after repair of tetralogy of Fallot is still continuing. We aim to clarify how the different components of right ventricle (RV) changed with relieved volume overload in the remodeling process after pulmonary valve replacement and gain a clear idea of the relationship between different right ventricle components function and exercise capacity after PVR in these patients. The medical records and results of cardiac magnetic resonance imaging and cardiopulmonary exercise testing of 25 consecutive eligible patients were reviewed. End-diastolic, end-systolic, and ejection fraction (EF) were determined for the total RV and its components before and after PVR. There was a marked increase in EF for the outlet after PVR (39.5 ± 11.4 vs. 45.6 ± 12.7, P = 0.04); however, EF and volume change for the other components showed no significant difference. Peak oxygen consumption (VO₂) correlated better with the RV outflow tract EF than with the EF of other components of the RV or the global EF (r = 0.382, P = 0.018), and the time interval between initial repair and PVR showed a significant correlation with peak VO₂ (r = -0.339, P = 0.037). Multivariate analysis showed the RV outflow tract EF to be the only independent predictor of exercise capacity (β = 0.479; P = 0.046). The systolic function of the RV outflow tract could be a reliable determinant of intrinsic RV performance in repaired TOF (rTOF) patients and a promising parameter for deciding timing of pulmonary valve replacement so as to achieve the best possible exercise capacity in repaired TOF patients.

Effect of ventricular function and volumes on exercise capacity in adults with repaired Tetralogy of Fallot

Objectives

Investigate the effects of left and right ventricular function and severity of pulmonary valve regurgitation, quantified by cardiac magnetic resonance (CMR), on exercise tolerance in adult patients who underwent ToF repair at a young age.

Methods

This is a retrospective cohort study of 52 patients after ToF surgery and 33 age- and sex-matched healthy volunteers. CMR and cardiopulmonary exercise testing (CPET) were performed on all patients; CPET was performed on control subjects.

Results

The main finding of CPET was a severe decrease in oxygen uptake at peak exercise VO_2peak in TOF patients. The patients were characterized also by lower pulse O_2peak and heart rate at peak exercise. Ejection fraction of the right and left ventricles was correlated (r = 0,32; p = 0,03). Left ventricle ejection fraction was negatively correlated with right ventricular volumes (r = −0,34; p = 0,01) and right ventricular mass (r = −046; p < 0,00). Right ventricular mass was positively correlated with left ventricular variables (left ventricle end diastolic volume, r = 0,43; p = 0,002; left ventricle end systolic volume, r = 0,54; p < 0,00) as was VO_2peak: LVEDV (r = 0,38; p = 0,01); LVESV (r = 0,33; p = 0,03) and LV mass (r = 0,42; p = 0,006).

Conclusion

Exercise intolerance in adults with repaired ToF is markedly depressed. The decreased exercise capacity is correlated with impaired RV function and may be associated also with LV dysfunction, which suggests right-to-left ventricular interaction.