Assessment of Right Ventricular-Pulmonary Arterial Coupling in Chronic Pulmonary Regurgitation.

BACKGROUND: We hypothesized that noninvasively measured right ventricular (RV) to pulmonary arterial (RV-PA) coupling would be abnormal in chronic pulmonary regurgitation (PR) even in the setting of normal RV ejection fraction, and that RV-PA coupling indices would have a better correlation with peak oxygen consumption (VO2) compared with RV systolic indices alone. METHODS: This was a retrospective study of 129 adults (repaired tetralogy of Fallot [TOF] n = 84 and valvular pulmonic stenosis [VPS] with previous intervention n = 45) with ≥ moderate native PR and RV ejection fraction > 50%. The 84 TOF patients were propensity matched with 84 patients with normal echocardiogram (control); age 28 ± 7 years and male sex n = 39 (46%). RV-PA coupling was measured according to fractional area change (FAC)/RV systolic pressure (RVSP) and tricuspid annular plane systolic excursion (TAPSE)/RVSP. RESULTS: RV systolic function indices were similar between TOF and control groups (FAC 43 ± 6% vs 41 ± 5% [P = 0.164] and TAPSE 22 ± 5 mm vs 24 ± 6 mm [P = 0.263]). However, RV-PA coupling was lower in the TOF group (FAC/RVSP 1.10 ± 0.29 vs 1.48 ± 0.22 [P < 0.001]; TAPSE/RVSP 0.51 ± 0.15 vs 0.78 ± 0.11 [P < 0.001]) because of higher RV afterload (RVSP 42 ± 3 mm Hg vs 31 ± 3 mm Hg [P = 0.012]). FAC/RVSP (r = 0.61; P < 0.001) and TAPSE/RVSP (r = 0.69; P < 0.001) correlated with peak VO2 especially in the patients with impaired exercise capacity whereas FAC and TAPSE were independent of peak VO2. Similar comparisons between VPS and control groups showed no difference in TAPSE and FAC between groups, but lower FAC/RVSP and TAPSE/RVSP in the VPS group. CONCLUSIONS: There is abnormal RV-PA coupling in chronic PR, and noninvasively measured RV-PA coupling might potentially be prognostic because of its correlation with exercise capacity.

3D-assessment of RVOT dimensions prior percutaneous pulmonary valve implantation: comparison of contrast-enhanced magnetic resonance angiography versus 3D steady-state free precession sequence.

To compare contrast-enhanced magnetic resonance angiography (ceMRA) and 3D steady-state free precession (SSFP) during systole and diastole for assessment of the right ventricle outflow tract (RVOT) in patients considered for percutaneous pulmonary valve implantation (PPVI) after tetralogy of Fallot (TOF) repair. We retrospectively evaluated 89 patients (male: 45, mean age 19 ± 8 years), who underwent cardiac-MRI after surgical TOF-repair. Datasets covering the whole heart in systole and diastole were acquired using ECG-gated 3D SSFP and non-gated ceMRA. Measurements were performed in SSFP-sequences and in ceMRA in the narrowest region of the RVOT to obtain the minimum, maximum and effective diameter. Invasive balloon sizing as the gold standard was available in 12 patients. The minimum diameter in diastolic SSFP, systolic SSFP and ceMRA were 21.4 mm (± 6.1 mm), 22.6 mm (± 6.2 mm) and 22.6 mm (± 6.0 mm), respectively. Maximum diameter was 29.9 mm (± 9.5 mm), 30.0 mm (± 7.0 mm) and 28.8 mm (± 8.1 mm) respectively. The effective diameter was 23.2 mm (± 5.7 mm), 27.4 mm (± 6.7 mm) and 24.4 mm (± 6.2 mm), differing significantly between diastole and systole (p < 0.0001). Measurements in ECG-gated SSFP showed a better inter- and intraobserver variability compared to measurements in non-ECG-gated ceMRA. Comparing invasive balloon sizing with our analysis, we found the highest correlation coefficients for the maximum and effective diameter measured in systolic SSFP (R = 0.99 respectively). ECG-gated 3D SSFP enables the identification and characterization of a potential landing zone for PPVI. The maximum and effective systolic diameter allow precise sizing for PPVI. Patients with TOF-repair could benefit from cardiac MRI before PPVI.

Percutaneous Versus Surgical Pulmonic Valve Implantation for Right Ventricular Outflow Tract Dysfunction.

BACKGROUND/PURPOSE: Percutaneous pulmonic valve implantation (PPVI) is an alternative treatment strategy to surgical pulmonic valve implantation (SPVI) for right ventricular outflow tract (RVOT) dysfunction. This study sought to compare outcomes of both treatment strategies. METHODS: The study population was extracted from the 2014 Nationwide Readmissions Database (NRD) using International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) codes for PPVI and SPVI. Study outcomes included all-cause in-hospital mortality, length of index hospital stay (LOS), post-procedural bleeding, mechanical complications of heart valve prosthesis, vascular complications (VC), infective endocarditis (IE), total hospitalization charges, and 30-day readmission rates. RESULTS: A total of 975 patient discharges (176 in PPVI and 799 in SPVI group) were identified (average age 25.7 years; 57.5% male). PPVI was associated with significantly shorter median LOS (1 versus 5 days, p < 0.01), lower risk of bleeding (4.6% versus 26.4%, p < 0.01), and lower total hospitalization charges ($169,551.7 versus $210,681.8, p = 0.02). There was no significant difference between both groups in terms of all-cause in-hospital mortality (0% versus 1.4%, p = 0.12), mechanical complications of heart valve prosthesis (1.7% versus 2.0%, p = 0.78), VC (2.3% versus 2.0%, p = 0.82), IE (1.7% versus 3.1%, p = 0.31), or 30-day readmission rates (4.4% versus 7.6%, p = 0.16). CONCLUSION: Compared with SPVI, PPVI was associated with shorter LOS, lower bleeding, and lower total charges. There was no significant difference between the two strategies in terms of all-cause in-hospital mortality, mechanical complications of heart valve prosthesis, VC, IE, or 30-day readmission rates.

Sequential Right and Left Ventricular Assessment in Posttetralogy of Fallot Patients with Significant Pulmonary Regurgitation.

BACKGROUND: The natural history of right ventricular (RV) and left ventricular (LV) size and function among adults with tetralogy of Fallot (TOF) repair and hemodynamically significant pulmonary regurgitation (PR) is not known. The main aim of this study was to determine changes in RV and LV size and function over time in an adult population with TOF repair and hemodynamically significant pulmonary regurgitation. METHODS: Forty patients with repaired TOF and hemodynamically significant PR were included. These patients were identified on the basis of having more than one CMR between January 2008 and 2015. Patients with a prosthetic pulmonary valve or any cardiac intervention between CMR studies were excluded. Rate of progression (ROP) of RV dilation was determined for both indexed right ventricular end-systolic volume (RVESVi) and indexed right ventricular end-diastolic volume (RVEDVi), and calculated as the difference between the last and first volumes divided by the number of years between CMR#1 and CMR#2. Subjects were also divided into two groups based on the distribution of the ROP of RV dilation: Group I-rapid ROP (>50th percentile) and Group II-slower ROP (≤50th percentile). RESULTS: The interval between CMR#1 and CMR#2 was 3.9 ± 1.7 years (range 1-8 years). We did find a significant change in RVEDVi and RVESVi over this time period, although the magnitude of change was small. Nine patients (23%) had a reduction in right ventricular ejection fraction (RVEF) by greater than 5%, 13 patients (33%) had an increase in RVEDVi by greater than 10 mL/m2 and seven patients (18%) had an increase in RVESVi by greater than 10 mL/m2 . Median ROP for RVEDVi was 1.8 (range -10.4 to 21.8) mL/(m2 year); RVESVi 1.1 (range -5.8 to 24.5) mL/(m2 year) and RVEF -0.5 (range -8 to 4)%/year. Patients with a rapid ROP had significantly larger RV volumes at the time of CMR#1 and lower RVEF as compared to the slow ROP group. There was no overall significant change in LVEDVi, LVESVi, or LVEF over this time period. CONCLUSIONS: We have demonstrated, in a small population of patients with hemodynamically significant PR, that there is a small increase in RV volumes and decrease in RVEF over a mean 4-year period. We believe it to be reasonable practice to perform CMR at least every 4 years in asymptomatic patients with repaired TOF and hemodynamically significant PR. We found that LV volumes and function remained stable during the study period, suggesting that significant progressive LV changes are less likely to occur over a shorter time period. Our results inform a safe standardized approach to monitoring adults with hemodynamically significant PR post TOF repair and assist in planning allocation of this expensive and limited resource.

Pulmonary valve replacement and quality-of-life assessment.

BACKGROUND: Chronic pulmonary regurgitation is common after repair of tetralogy of Fallot. Despite the deleterious effects of chronic pulmonary regurgitation on right ventricular function, many patients with repaired tetralogy of Fallot remain asymptomatic. Health is defined not only by the absence of disease but also by physical, mental, and social wellbeing. We sought to examine the impact of pulmonary valve replacement on quality of life in asymptomatic patients with repaired tetralogy of Fallot and chronic pulmonary regurgitation. METHODS: From January 2009 to December 2012, 25 (18 male) asymptomatic patients (mean age 23.4 ± 7.4 years) who underwent pulmonary valve replacement for significant pulmonary regurgitation were recruited. Cardiac magnetic resonance was performed pre- and postoperatively. Quality of life was assessed using the Chinese version of the SF-36v2 evaluation tool. Demographics, clinical data, magnetic resonance findings, and quality-of-life scores were collected and calculated for comparison. RESULTS: After surgery, the indexed right ventricular end-diastolic volume (193 ± 47.3 vs. 105.6 ± 29.6 mL m(-2), p < 0.001) and indexed right ventricular end-systolic volume (108.5 ± 32.9 vs. 61.1 ± 23 mL m(-2), p < 0.001) decreased significantly. The response rates for pre- and postoperative quality-of-life assessments were 100%. Patients demonstrated improvements in all 8 domains of the SF-36v2 assessment. The physical (46.5 ± 6.6 vs. 49.9 ± 6.4, p = 0.012) and mental (43.7 ± 7.8 vs. 51.9 ± 7.6, p < 0.001) component summary scores increased after surgery. CONCLUSION: Pulmonary valve replacement can improve the quality of life in patients with chronic asymptomatic pulmonary regurgitation.

Methodology for implementing patient-specific spatial boundary condition during a cardiac cycle from phase-contrast MRI for hemodynamic assessment.

Pulmonary insufficiency (PI) can render the right ventricle dysfunctional due to volume overloading and hypertrophy. The treatment requires a pulmonary valve replacement surgery. However, determining the right time for the valve replacement surgery has been difficult with currently employed clinical techniques such as, echocardiography and cardiac MRI. Therefore, there is a clinical need to improve the diagnosis of PI by using patient-specific (PS) hemodynamic endpoints. While there are many reported studies on the use of PS geometry with time varying boundary conditions (BC) for hemodynamic computation, few use spatially varying PS velocity measurement at each time point of the cardiac cycle. In other words, the gap is that, there are limited number of studies which implement both spatially- and time-varying physiologic BC directly with patient specific geometry. The uniqueness of this research is in the incorporation of spatially varying PS velocity data obtained from phase-contrast MRI (PC-MRI) at each time point of the cardiac cycle with PS geometry obtained from angiographic MRI. This methodology was applied to model the complex developing flow in human pulmonary artery (PA) distal to pulmonary valve, in a normal and a subject with PI. To validate the methodology, the flow rates from the proposed method were compared with those obtained using QFlow software, which is a standard of care clinical technique. For the normal subject, the computed time average flow rates from this study differed from those obtained using the standard of care technique (QFlow) by 0.8 ml/s (0.9%) at the main PA, by 2 ml/s (3.4%) at the left PA and by 1.4 ml/s (3.8%) at the right PA. For the subject with PI, the difference was 7 ml/s (12.4%) at the main PA, 5.5 ml/s (22.6%) at the left PA and 4.9 ml/s (18.0%) at the right PA. The higher percentage differences for the subject with PI, was the result of overall lower values of the forward mean flow rate caused by excessive flow regurgitation. This methodology is expected to provide improved computational results when PS geometry from angiographic MRI is used in conjunction with PS PC-MRI data for solving the flow field.

Multivariable assessment of the right ventricle by echocardiography in patients with repaired tetralogy of Fallot undergoing pulmonary valve replacement: a comparative study with magnetic resonance imaging.

BACKGROUND: Evaluation of the right ventricle (RV) using transthoracic echocardiography is challenging in patients with repaired tetralogy of Fallot (rTOF). AIMS: To evaluate the accuracy of conventional echocardiographic variables and real-time three-dimensional echocardiography (RT3DE) in assessing right ventricular (RV) volumes and function compared with magnetic resonance imaging (MRI), in adult patients with rTOF and referred for pulmonary valve replacement (PVR). METHODS: Complete echocardiography was performed on 26 consecutive patients referred for PVR, before and 1 year after surgery. All variables were compared with MRI. RESULTS: Correlations between conventional variables and MRI were absent or poor when assessing RV ejection fraction (RVEF), except for fractional area of change (FAC; r=0.70, P<0.01 before PVR; r=0.68, P<0.01 after PVR) and RT3DE (r=0.96, P<0.01 before PVR; r=0.98, P<0.01 after PVR). The RV volume correlation between RT3DE and MRI was excellent before and after surgery for RV end-diastolic volume (r=0.88, P<0.01 and r=0.91, P<0.01, respectively) and RV end-systolic volume (r=0.92, P<0.01 and r=0.95, P<0.01, respectively). The accuracy of these indices, as a diagnostic test for impaired RV (<45%), was good: Youden's indexes varied from 0.47 to 0.89; areas under the receiver operating characteristic curve before and after PVR were 0.86 and 0.81 for FAC and 0.98 and 0.97 for RT3DE, respectively. CONCLUSION: Commonly used echocardiography variables, such as tricuspid annular plane systolic excursion and tricuspid annular peak systolic velocity, did not sensitively evaluate global RVEF. A global approach, that includes the whole RV and integration of its different components, was more reliable in patients with rTOF.

Hemodynamic outcomes of transcatheter aortic valve implantation with the CoreValve system: an early assessment.

BACKGROUND AND AIMS: Transcatheter aortic valve implantation (TAVI) is an established method for the treatment of high-risk patients with aortic stenosis (AS). The beneficial effects of TAVI in cardiac hemodynamics have been described in recent studies, but those investigations were mostly performed after an interval of more than 6 months following aortic valve implantation. The aim of this study is to investigate the acute and short-term alterations in hemodynamic conditions using the echocardiography outcomes in patients undergoing TAVI. METHODS AND RESULTS: A total of 60 patients (26 males, 34 females; age 84·7 ± 5·8) who underwent TAVI with CoreValve system were included in the study. Echocardiography was performed before hospital discharge and at 3 months follow-up. As expected, TAVI was associated with an immediate significant improvement in aortic valve area (AVA) (from 0·64 ± 0·16 cm(2) to 1·67 ± 0·41 cm(2) , P-value<0·001) and mean gradient (from 51·9 ± 15·4 mmHg to 8·8 ± 3·8 mmHg, P-value<0·001). At 3-month follow-up, systolic LV function was augmented (EF: 50 ± 14% to 54 ± 11%, P-value = 0·024). Left ventricle (LV) mass and left atrium (LA) volume were significantly reduced (LV mass index from 126·5 ± 30·5 g m(-2) to 102·4 ± 32·4 g m(-2) ; LA index from 42·9 ± 17·3 ml m(-2) to 33·6 ± 10·6 ml m(-2) ; P-value<0·001 for both). Furthermore, a decrement in systolic pulmonary artery pressure (SPAP) from 47·5 ± 13·5 mmHg to 42·5 ± 11·2 mmHg, P-value = 0·02 was also observed. Despite the high incidence of paravalvular regurgitation (PVR) (80%), most of the patients presented mild or trace PVR and no significant progress of the regurgitation grade was seen after 3 months. CONCLUSION: This study demonstrates that the beneficial effects of TAVI in cardiac function and hemodynamics occur already after a short period following aortic valve implantation.

Assessment of left ventricular preload by cardiac magnetic resonance imaging predicts exercise capacity in adult operated tetralogy of Fallot: a retrospective study.

BACKGROUND: The optimal timing of pulmonary homograft valve replacement (PVR) is uncertain. Cardiopulmonary exercise testing (CPET) and cardiac magnetic resonance (CMR) are often used to guide the clinical decision for PVR in operated tetralogy of Fallot (TOF) patients with significant pulmonary regurgitation (PR). We aim to study the relationship between exercise capacity and CMR in these patients. METHODS: The study is a single-centre retrospective analysis of 36 operated TOF patients [median 21.4 (interquartile range 16.4, 26.4) years post-repair; 30 NYHA I, 6 NYHA II; median age 25.2 (interquartile range 19.5-31.7) years, 29 males] with significant PR on CMR who underwent CPET within 15 [median 2.0 (interquartile range 0.8-7.2)] months from CMR. CPET parameters were compared with 30 age- and sex-matched healthy controls [median age 27.8 (interquartile range 21.0-32.8) years; 24 males]. RESULTS: Peak systolic blood pressure (177 versus 192 mmHg, p = 0.007), Mets (7.3 versus 9.9, p < 0.001), peak oxygen consumption (VO2max) (29.2 versus 34.5 ml/kg/min, p < 0.001) and peak oxygen pulse (11.0 versus 13.7 ml/beat, p = 0.003) were significantly lower in TOF group versus control. Univariate analyses showed negative correlation between PR fraction and anaerobic threshold. There was a positive correlation between indexed left (LV) and right (RV) ventricular end-diastolic volumes, as well as indexed LV and effective RV stroke volumes, on CMR and VO2max and Mets achieved on CPET. These remained significant after adjustment for age and sex. CONCLUSIONS: TOF subjects have near normal exercise capacity but significantly lower Mets, VO2max and peak oygen pulse achieved compared to controls. Increased PR fraction in TOF subjects was associated with lower anaerobic threshold. Higher indexed effective RV stroke volume, a measure of LV preload, was associated with higher VO2max and Mets achieved, and may potentially be used as a predictor of exercise capacity.

Quantitative assessment of right ventricular function and pulmonary regurgitation in surgically repaired tetralogy of Fallot using 256-slice CT: comparison with 3-Tesla MRI.

OBJECTIVES: To compare 256-slice cardiac computed tomography (CCT) with cardiac magnetic resonance (CMR) imaging to assess right ventricular (RV) function and pulmonary regurgitant fraction (PRF) in patients with repaired tetralogy of Fallot (TOF). METHODS: Thirty-three consecutive patients with repaired TOF underwent retrospective ECG-gated CCT and 3-Tesla CMR. RV and left ventricular (LV) end-diastolic volume (EDV), end-systolic volume (ESV), stroke volume (SV) and ejection fraction (EF) were measured using CCT and CMR. PRF-CCT (%) was defined as (RVSV - LVSV)/RVSV. PRF-CMR (%) was measured by the phase-contrast method. Repeated measurements were performed to determine intra- and interobserver variability. RESULTS: CCT measurements, including PRF, correlated highly with the CMR reference (r = 0.71-0.96). CCT overestimated RVEDV (mean difference, 17.1 ± 2.9 ml), RVESV (12.9 ± 2.1 ml) and RVSV (4.2 ± 2.0 ml), and underestimated RVEF (-2.6 ± 1.0%) and PRF (-9.1 ± 2.0%) compared with CMR. The limits of agreement between CCT and CMR were in a good range for all measurements. The variability in CCT measurements was lower than those in CMR. The estimated effective radiation dose was 7.6 ± 2.6 mSv. CONCLUSIONS: 256-slice CCT can assess RV function and PRF with relatively low dose radiation exposure in patients with repaired TOF, but overestimates RV volume and underestimates PRF. KEY POINTS: 256-slice CT assessment of RV function is highly reproducible in repaired TOF. Pulmonary regurgitation can be evaluated by biventricular systolic volume difference. CT overestimates RV volume and underestimates pulmonary regurgitation, compared with MRI.

CMR assessment of right ventricular function in patients with combined pulmonary stenosis and insufficiency after correction of tetralogy of Fallot.

BACKGROUND: Tetralogy of Fallot (TOF) is one of the most common types of congenital heart disease and requires prompt surgical correction. Post-correction pulmonary insufficiency (PI) often ensues in adulthood. At times, the PI is accompanied by residual pulmonary stenosis (PS). Little is known regarding right ventricular (RV) function in the setting of combined PS and PI. PURPOSE: To compare cardiac magnetic resonance (CMR) parameters for the assessment of RV function between patients with combined pulmonary stenosis and pulmonary insufficiency (PSPI) and isolated PI following surgical repair of TOF. MATERIAL AND METHODS: Retrospective review of patients with comparable corrected TOF and similar PI was performed. Seventeen patients (median age, 24 years; range, 10-52 years) had combined PSPI and 30 patients (median age, 30 years; range, 6-70 years) had isolated PI. Cine magnetic resonance (MR) images (Philips Medical Systems, Best, The Netherlands) in the short-axis plane were used to calculate end-systolic, end-diastolic, and stroke volumes (RVESV, RVEDV, RVSV) and to measure RV wall thickness. Velocity-encoded cine MR images were used to measure pulmonary regurgitation fraction (PRF) by calculating the ratio of backward flow and total forward flow, obtained from the main pulmonary flow analysis. Peak pressure gradient across the pulmonary valve was obtained from spectral Doppler echocardiography. RESULTS: RVEF was 51 ± 8% in the PSPI patients and 39 ± 11%, in the patients with isolated PI (P = 0.001). Additionally, RV wall thickness was 5.2 ± 0.8 mm in the PSPI patients compared to 2.6 ± 0.9 mm in the isolated PI patients (P = 0.001). RVESVi and RVEDVi were significantly lower (P < 0.05) in patients with combined PSPI (60 ± 21 mL/m(2), 121 ± 35 mL/m(2), respectively) compared to the patients with isolated PI (95 ± 48 mL/m(2), 152 ± 61 mL/m(2), respectively). CONCLUSION: RV function is preserved in patients with PSPI when compared to patients with PI following surgical repair of TOF.

Volumetric and functional assessment using cardiac magnetic resonance imaging in young children exposed to acute pulmonary regurgitation: is pulmonary regurgitation just a long-term matter?

BACKGROUND: The early effect of pulmonary regurgitation (PR) on both ventricular volume and function has not been well established in children. We evaluated the early effect of PR on both ventricular volume and function in young children. METHODS: Among patients who underwent total repair of pulmonary atresia with ventricular septal defect between January 2007 and December 2008, cardiac magnetic resonance imaging (CMRI) was performed in 12 patients at a median interval of 15.6 months (6-22 months). Valveless right ventricular outflow tract (RVOT) reconstruction was performed in five patients (valveless group) and RVOT reconstruction using valved conduit in seven patients (valve group). Age and weight at operation, and the interval between the operation and CMRI were not different between the groups. RESULTS: We observed a higher pulmonary regurgitant fraction (p = 0.003), a higher right ventricular end-diastolic volume index (RVEDVI) (p = 0.003), a higher right ventricular end-systolic volume index (p = 0.003), a higher left ventricular end-diastolic volume index (p = 0.010), a higher left ventricular end-systolic volume index (p = 0.018), and a lower left ventricular ejection fraction (LVEF; p = 0.048) in the valveless group. Right ventricular ejection fraction (RVEF) was not different between two groups. The RVEDVI was negatively correlated with RVEF (rho = -0.601, p = 0.039) and LVEF (rho = -0.580, p = 0.048). CONCLUSIONS: Both ventricular volumes increased and left ventricular function was compromised, but right ventricular function was preserved early after the exposure to PR in children. Right ventricular volume was associated with both ventricular functions.

Echocardiographic assessment of diastolic biventricular properties in patients operated for severe pulmonary regurgitation and association with exercise capacity.

AIMS: We aimed to assess the impact of surgical pulmonary valve replacement (PVR) for severe pulmonary regurgitation (PR) on biventricular function and its effect on exercise capacity. METHODS AND RESULTS: Seventy-three patients (mean age 23.6±11.5 years, 47 females) underwent surgical PVR for PR. Echocardiogram and magnetic resonance imaging to assess ventricular size and function, and a cardiopulmonary exercise test were performed before, and 1-year post-surgery. Median New York Heart Association class improved from 2 to 1 but peak oxygen uptake (VO2) did not change. Left ventricular (LV) cardiac output increased from 3.2±0.9 to 3.5±0.7 L/min (P=0.003). However, this was not associated with increased trans-mitral velocities (▵E=-0.13, P=0.004; ▵A=0.03, P=0.395), or increased heart rate (-0.002%, P=0.993). Trans-tricuspid rapid right ventricular (RV) filling increased significantly, whereas early diastolic myocardial velocity in RV wall decreased (E velocity: 0.57±0.14-0.65±0.21, P=0.034; and E/e' from 6.7±1.9 to 14.8±7.0, P<0.0001). RV and LV late diastolic velocities and their ratio to early velocities (A, a', E/A, and e'/a') correlated with pre- and/or post-PVR peak VO2. No correlations were found between indexes of systolic function and peak VO2, either before or after surgery. Doppler evidence of restrictive RV physiology resolved after elimination of PR. CONCLUSION: Surgical PVR for PR improves RV filling and increases left ventricular stroke volume, however, this could not be demonstrated by conventional Doppler echocardiography. Diastolic ventricular function was associated with exercise capacity. Because of its load dependency, E/e' ratio failed in assessing diastolic function. Pre-systolic flow in pulmonary trunk in presence of severe PR does not determine intrinsic myocardial stiffness.

Quantitative assessment of pulmonary regurgitation in patients with and without right ventricular tract obstruction.

BACKGROUND: There are concerns whether there is a difference in clinical utility of pulmonary regurgitation (PR) fraction (PRF) and PR volume (PRV) in subgroups of patients with isolated PR and individuals with combined PR and right ventricular outflow tract obstruction (RVOTO). The aim of the study was to compare PRF and PRV in patients with or without RVOTO. METHODS AND RESULTS: 82 consecutive patients after repair of tetralogy of Fallot (TOF) who underwent cardiovascular magnetic resonance and echocardiography were studied. There was no difference in PRF between patients with moderate and severe right ventricular (RV) dilatation (32±13% vs. 37±12%; p=0.18). Significant difference in PRV was observed between these groups (23±10 ml/m2 vs. 31±12 ml/m2, respectively; p=0.02). PRV had better ability than PRF in identification of severe RV dilatation, both in group with RVOTO [area under the curve (AUC) 0.82 vs. 0.72, p=0.005] and in patients without RVOTO (AUC 0.83 vs. 0.77, p=0.04). A strong correlation was seen between PRF and PRV both in patients with and without RVOTO [r=0.93, p<0.0001 and r=0.92, p<0.0001, respectively]. In both subgroups high variability of PRF was found in subjects with similar degree of PRV. CONCLUSIONS: PRV shows better ability than PRF in evaluating influence of PR on RV in patients after TOF repair, both in population with and without concomitant RVOTO.

Flow assessment through four heart valves simultaneously using 3-dimensional 3-directional velocity-encoded magnetic resonance imaging with retrospective valve tracking in healthy volunteers and patients with valvular regurgitation.

OBJECTIVES: To validate 3-dimensional (3D) 3-directional velocity-encoded (VE) magnetic resonance imaging (MRI) for flow assessment through all 4 heart valves simultaneously with retrospective valve-tracking during off-line analysis in healthy volunteers and in patients with valvular regurgitation. MATERIAL AND METHODS: Three-dimensional 3-directional VE MRI was performed in 22 healthy volunteers and in 29 patients with ischemic cardiomyopathy who were suspected of valvular regurgitation and net flow volumes through the 4 heart valves were compared. Furthermore, the analysis was repeated for each valve in 10 healthy volunteers and in 10 regurgitant valves to assess intra- and interobserver agreement for assessment of respectively net flow volumes and regurgitation fraction. RESULTS: In healthy volunteers, the average net flow volume through the mitral valve, tricuspid valve, aortic valve, and pulmonary valve was 85 +/- 20 mL, 85 +/- 21 mL, 83 +/- 19 mL, 82 +/- 21 mL, respectively. Strong correlations between net flow volumes through the 4 heart valves were observed (intraclass correlation coefficients [ICC] 0.93-0.95) and the coefficient of variance (CV) was small (6%-9%). The repeated analysis by the same observer and by a second observer yielded good agreement for measurement of net flow volumes (ICC: 0.93-0.99 and CV: 3%-7%). Strong correlations between the net flow volumes through the 4 heart valves were also observed in the patients with valvular regurgitation (ICC: 0.85-0.95 and CV: 7%-18%). The average net flow volume through the mitral valve, tricuspid valve, aortic valve, and pulmonary valve was 63 +/- 20 mL, 63 +/- 20 mL, 63 +/- 20 mL, 63 +/- 20 mL, respectively. Furthermore, the intra- and interobserver agreement for assessment of regurgitation fraction was good (ICC: 0.86 and 0.85, CV: 12% and 13%). CONCLUSIONS: Flow assessment using 3D 3-directional VE MR with retrospective valve-tracking during off-line analysis enables accurate quantification of net flow volumes through 4 heart valves within a single acquisition in healthy volunteers and in patients with valvular regurgitation.

Quantitative assessment of homograft function 1 year after insertion into the pulmonary position: impact of in situ homograft geometry on valve competence.

AIMS: To prospectively evaluate homograft function with cardiac magnetic resonance (CMR) imaging 1 year after insertion into the pulmonary position, and to assess the impact of in situ homograft geometry, surgical factors, and 'intrinsic' homograft properties on early valve incompetence. METHODS AND RESULTS: A total of 60 patients (mean age 21 +/- 10 years; 35 females) with congenital heart disease underwent pulmonary valve replacement with homograft insertion and were prospectively enrolled into a study protocol that included serial echocardiography and CMR 1 year after surgery. None of the patients had homograft stenosis but 10 (17%) had significant homograft incompetence (i.e. pulmonary regurgitation fraction >20% on CMR). A higher incidence of 'eccentric' pulmonary forward flow pattern (P < 0.001, Fisher's exact test), more acute 'homograft distortion angle' (P < 0.001), larger relative 'annular' size (P < 0.01), and greater pre-homograft right ventricular outflow tract (RVOT) diameters (P = 0.01) at CMR was seen in those with worse homograft function. In a backward multivariate linear regression model, 'eccentric' pulmonary forward flow pattern (r(part) = 0.36, P < 0.001), 'homograft distortion angle' (r(part) = 0.31, P = 0.001), and pre-homograft RVOT diameter (r(part) = 0.19, P = 0.03) were independently associated with the degree of pulmonary regurgitation (in %) at 1 year. CONCLUSION: Using CMR, in this prospective cohort study, we have shown that significant valve incompetence is present in one-sixth of patients after homograft insertion into the pulmonary position, and that alterations in the in situ homograft geometry were associated with the likelihood of developing valve incompetence. These findings imply that mechanical factors may have an important impact on homograft performance.

[Right ventricular assessment with echocardiography]. / Analyse échocardiographique du ventricule droit.

Right ventricular (RV) function is essential in cardio--pulmonary physiology and physiopathology. RV dysfunction has prognostic impact in inferior myocardial infarction, significant valvulopathies, congenital cardiopathies, arterial pulmonary hypertension and in patients suffering from acute or chronic heart failure. RV analysis relies on non invasive (echocardiography-Doppler, isotopic technology, cardiac magnetic resonance imaging) and/or invasive approaches (right cardiac catheterization). Neglected a short time ago, RV assessment has regained interest with tissular Doppler imaging, strain imaging and 2D speckle tracking. We review echocardiography and Doppler -parameters used for right -ventricular assessment.

Assessment of myocardial function in pediatric patients with operated tetralogy of Fallot: preliminary results with 2D strain echocardiography.

The global myocardial function in patients after repair of tetralogy of Fallot (TOF) can be assessed by cardiovascular magnetic resonance (CMR) and measurement of B-type natriuretic peptides. Two-dimensional echocardiography-derived strain and strain rate (2D strain) facilitate the assessment of regional myocardial function. We evaluated myocardial function in 16 children with residual severe pulmonary valve regurgitation and right ventricular (RV) volume overload after TOF repair before, 1 month after, and 6 months after pulmonary valve replacement (PVR). In 2D strain echocardiography preoperatively, the longitudinal systolic RV strain was reduced (p < 0.05). One month after PVR, longitudinal systolic RV strain decreased further (p < 0.05), while systolic and early diastolic radial left ventricular strain and strain rate increased (each p < 0.05), followed by a return toward preoperative values after 6 months. Six months after PVR, preoperatively elevated RV end-diastolic volume (p < 0.01) assessed by CMR and N-terminal pro-B-type natriuretic peptide (p < 0.05) decreased. In conclusion, the impairment of the regional myocardial after TOF repair and transient changes after PVR can be subtly analyzed by 2D strain echocardiography in addition to the established assessment of myocardial function with CMR and measurement of B-type natriuretic peptides.

Doppler-echocardiographic assessment of pulmonary regurgitation in adults with repaired tetralogy of Fallot: comparison with cardiovascular magnetic resonance imaging.

AIMS: The purpose of this study was to compare the noninvasive assessment of severity of pulmonary regurgitation with Doppler echocardiography versus cardiovascular magnetic resonance imaging (CMR) in adult patients with repaired tetralogy of Fallot (rTOF). METHODS: We studied 52 (22 females) consecutive patients (aged 32 +/- 2 years, 23 +/- 5 years after rTOF) using Doppler echocardiography and compared these findings with CMR. From the continuous-wave Doppler trace, the duration of pulmonary regurgitation and of total diastole was measured and the ratio between the 2 was defined as pulmonary regurgitation index (PRi). Pulmonary regurgitant fraction (PRF) was assessed with flow phase velocity mapping with CMR. RESULTS: Patients were divided into 2 groups according to the median value (24.5%) of PRF measured by CMR: Group I (26 patients) with PRF < or =24.5% and Group II with PRF >24.5%. There was no difference between patients' age, sex, or age at repair between the 2 groups. More patients from Group II had a right ventricular outflow or transannular patch repair compared to Group I (12/26 [46%] vs 6/26 [23%], P <.01). Mean pulmonary regurgitation time was shorter (340 +/- 60 vs 440 +/- 135 ms, P =.001) and PRi was lower (0.61 +/- 0.11 vs 0.91 +/- 0.11, P <.001) in Group II compared to Group I. Color Doppler regurgitant jet was also broader in Group II (1.4 +/- 0.4 vs 0.7 +/- 0.5 cm, P <.001), signifying more severe pulmonary regurgitation. Doppler-measured PRi correlated closely with CMR regurgitant fraction (r = -0.82, P <.001) and with color Doppler pulmonary regurgitant jet width (r = -0.66, P <.001); the latter correlated with PRF assessed with CMR (r = 0.72, P <.001). A PRi <0.77 had 100% sensitivity and 84.6% specificity for identifying patients with pulmonary regurgitant fraction >24.5%, with a predictive accuracy of 95%. Furthermore, echocardiographically-assessed right ventricular end-diastolic dimensions correlated with CMR end-diastolic volume index (r = 0.49, P <.001 ). CONCLUSIONS: Pulmonary regurgitation is common in asymptomatic adults with rTOF. Severity of pulmonary regurgitation and its effects on right ventricular dimensions in these patients can be assessed noninvasively by Doppler echocardiography and CMR, with reasonable agreement between the 2 techniques.