Degree Of Pulmonary Regurgitation Research Articles

PHYSICAL AND MECHANICAL PROPERTIES OF CONDUITS DURING THE FORMATION OF THE OUTFLOW TRACT INTO THE PULMONARY ARTERY

HighlightsWe have evaluated the rigidity and distensibility of conduits in the long-term period using transthoracic echocardiography. The assessment of elastic properties will make it possible to predict degenerative changes in the conduit and choose the optimal prosthesis. AbstractAim. To evaluate changes in the rigidity and distensibility of conduits in patients after the formation of an outflow tract into the pulmonary artery in comparison with the control group of “healthy” children.Methods. The prospective non-randomized two-center study included 58 people with right ventricular dysfunction who underwent primary conduit implantation between the ages of 3 and 15 years. To assess the elastic properties of the pulmonary artery, a control group of 25 patients (healthy children who agreed to participate in the study) was introduced. The study was carried out at the Meshalkin National Medical Research Center and the Almazov National Medical Research Centre. All patients were divided into 4 groups: healthy children (n = 25), formation of the outflow tract with a pulmonary homograft (n = 28), and formation of the outflow tract with Contegra conduit (n = 19), formation with a xenopericardial conduit (n = 11).Results. The only differences between the groups were the RV EDV index, RV CVD index, RV FIP, severe pulmonary regurgitation, and tricuspid regurgitation. There is a significant difference between the groups in the long-term period (after 12 and 24 months), both in terms of rigidity and elasticity. The only difference in the long-term period after 12 months was the degree of tricuspid regurgitation, which was significantly lower in the control group. After 24 months, the peak gradient between the right ventricle and the pulmonary artery was different, which was significantly higher in the group of xenopericardial conduits and the degree of pulmonary regurgitation, which was significantly lower in the control group.Conclusion. The conduits show higher stiffness in the long-term period in contrast to the normal pulmonary artery, which may affect the durability of the conduits.

Relationship of Balloon Size in Pulmonary Valvuloplasty Outcome

Objective: To evaluate the relation between balloon size and outcome of patients undergoing pulmonary valvuloplasty. Study Design: A quasi-experimental study. Place and Duration: Pediatric Cardiology Department of Chaudhary Pervaiz Elahi Institute of Cardiology, Multan, Pakistan from January 2021 to June 2022. Methodology: Children of both genders aged less than 15 years having severe pulmonary stenosis and who underwent pulmonary valvuloplasty during the study period were analyzed. After 24 hours post procedure, echocardiography was done to see echo gradient across pulmonary valve, tricuspid regurgitation, pulmonary regurgitation, right ventricular dysfunction or pericardial effusion. Procedure was considered successful if the residual gradient across pulmonary valve was < 40 mmHg, pulmonary regurgitation < moderate and patients had no major complications. Results: In a total of 75 children, 42 (56.3%) were male. The mean age was 6.24 ± 4.81 years. Cyanosis was observed in 10 (13.3%) children while there was right ventricular dysfunction in 6 (8.0%) children. The pulmonary valvuloplasty procedure was successful in 53 (70.6%) cases while in remaining 22 (29.4%) cases, the procedure was partially successful because of infundibular obstruction. We observed that the degree of pulmonary regurgitation was greater when annulus- balloon ratio was 1.3 or more than that (p<0.0001). Practical Implications: Large balloons do not impart advantages beyond that produced by balloons between 1.2-1.4 times of the annular size but further research is required to ascertain these findings Conclusion: Signification relation exists regarding balloon size and outcome of children undergoing pulmonary valvuloplasty as the degree of pulmonary regurgitation was greater when annulus- balloon ratio was 1.3 or more. Keywords: Cyanosis, pulmonary regurgitation, pulmonary valvuloplasty, right ventricular dysfunction.

Echocardiographic comparison between pulmonary valve preservation and transannular patch techniques in children with repaired Tetralogy of Fallot

Abstract Funding Acknowledgements Type of funding sources: None. INTRODUCTION Many centers have recently adopted pulmonary valve (PV) preservation procedures to prevent the detrimental long-term effects of chronic pulmonary regurgitation after tetralogy of Fallot (ToF) repair. PURPOSE The aim of our study was to investigate pulmonary valve (PV) and right ventricular function by echocardiography in paediatric patients with repaired Tetralogy of Fallot (ToF), comparing PV preservation surgical strategies to standard transannular patch (TAP) repair. METHODS All patients undergoing transatrial-transpulmonary repair for ToF at our institution between January 2007 and May 2020 were reviewed retrospectively. Patients were divided into 2 main groups, according to the different techniques used: patients undergoing a PV preservation strategy and patients undergoing TAP repair. All patients underwent standard echo-Doppler study including RV end-diastolic area (RVEDA), end-systolic area (RVESA), fractional area change (FAC) and TAPSE; PR was assessed by Color Doppler, continuous-wave (CW) Doppler and derived parameters such as pressure half time (PHT) and pulmonary regurgitation (PR) index. By speckle tracking we measured also, in a subgroup of patients, right atrial strain (RAS), RV and left ventricle (LV) global longitudinal strain (RVGLS, LVGLS) and their time to peak (TTP) values. RESULTS Overall, 82 patients underwent a successful PV preservation strategy while 34 underwent a standard TAP repair. At index surgery, BSA (0.31 ± 0.1 m2, P = 0.3), age (4.8 ± 0.3 months, P = 0.5) and preoperative PV Z-score (-3.20 ± 0.1, P = 0.1) did not different between groups. Five-year actuarial freedom from moderate/severe PV regurgitation was significantly higher in the PV preservation group compared to the TAP (61.3% [95% CI: 48-73%] vs 25.9% [95% CI: 12-43%], respectively; p = 0.02). After adjusting for age, gender, BSA, and type of PV, the use of a TAP was still significantly associated with an increased risk for PV regurgitation at follow up (HR: 1.85, 95% CI: 1.09, 3.15; p = 0.02). At a mean follow-up of 6.9 ± 0.3 years, patients undergoing PV preservation showed an increased right ventricular fractional area change (46.9 ± 0.8% vs 42.5 ± 1.7%, P < 0.001) and tricuspid annular plane systolic excursion (TAPSE) z-score (-3.36 ± 0.3% vs -4.7 ± 0.4%, P = 0.005), while maintaining better PV competence in terms of pulmonary regurgitation index (87.9 ± 1.2% vs 82.7 ± 2.4%, P = 0.02). At speckle tracking subanalysis, patients undergoing PV preservation (n= 23), compared to the TAP group (n = 13) showed also higher values of RAS (37.5 ± 6.0% vs 29.3 ± 8.2% , P < 0.006), shorter right TTP (319 ± 39ms vs 357.5 ± 45.2 ms, P < 0.01) and higher values of LVGLS (-20,6 ± 4,2% vs -17.5 ± 3.0, P < 0.03). CONCLUSIONS Surgical repair of ToF with PV preservation provides excellent outcomes in terms of PV competence and right ventricular function and should be advocated whenever possible. Abstract Figure. Degree of pulmonary regurgitation

Abstract 14576: Durability of Valve-sparing Tetralogy of Fallot Repair

Introduction: While valve-sparing repair is ideal for Tetralogy of Fallot (TOF), it’s durability and which patients may benefit from a transannular patch remains unclear. To this end, we reviewed our experience with valve-sparing TOF repair. Methods: Retrospective review was performed of all primary TOF operations at our institution from 1/2008 to 12/2018. Standard demographic, operative, and echo data were collected, along with clinical outcomes. Transannular patch and valve-sparing repair groups were then compared. Results: Sixty-eight patients underwent TOF repair with a mean age of 4.1±2.2 months and weight of 5.7±1.8 kg. There was no difference in age or weight between patients who underwent a transannular patch repair and valve-sparing repair (Table). There was also no difference in the frequency of hypercyanotic spells or beta-blocker use. As expected the pre-operative pulmonary valve size and z-score were significantly different between groups. Bypass times were longer in the transannular patch group (176±40 vs. 144±40 minutes, p=0.005). There were no differences in post-operative complications. At last follow-up (median 41.5 months) there was a trend of a higher peak pulmonary valve gradient (p=0.07) in the valve-sparing group, but no difference in pulmonary valve annulus z-scores. Additionally, the pulmonary valve z-scores in the valve-sparing group decreased from -2.3±1.0 on pre-discharge echocardiogram to -1.2±1.6 on last follow-up, with the peak gradient on pre-discharge 20 (33) mmHg stable on last follow-up at 18 (29) mmHg and degree of pulmonary regurgitation stable. There was one reoperation in the cohort: a pulmonary valve replacement in a patient who had undergone a transannular patch repair 6 years prior. Conclusions: Valve-sparing TOF patients demonstrated stable repairs with pulmonary valve growth, acceptable gradients, minimal regurgitation, and high freedom from re-intervention during follow-up.

Long-term follow-up of percutaneous balloon pulmonary valvuloplasty in pulmonary valve stenosis in 230 children

Objective To evaluate the safety and efficacy of percutaneous balloon pulmonary valvuloplasty (PBPV) in the treatment of the children with pulmonary stenosis (PS), and to observe the long-term prognosis and analyze the influencing factors. Methods The total of 230 children were collected, who had been diagnosed with pulmonary valve stenosis and had undergone percutaneous balloon pulmonary valvuloplasty between November 1987 and November 2015 in Shandong Provincial Hospital Affiliated to Shandong University.Their ages ranged from 4 months to 17 years, and the follow-up duration lasted from 1 month to 29 years.The data included clinical data and long-term follow-up data of hospitalized children, and the echocardiography data from the healthy peers in the same period.Then the data were analyzed statistically. Results In this study, 228 cases of children were successfully performed PBPV, and the success rate was 99%(228/230 cases). The pulmonary transvalvular gradient (△P) of preoperation, 24 hours postoperatively, half a year postoperatively, 2 years postoperatively, 5 years postoperatively, and 10 years postope-ratively was (63.5±23.8) mmHg(1 mmHg=0.133 kPa), (26.2±11.1) mmHg, (24.8±9.8) mmHg, (20.9±8.9) mmHg, (18.1±8.7) mmHg, (15.3±7.3) mmHg and (15.3±7.3) mmHg, respectively.The immediate postoperative △P was significantly lower than that of preoperation (P<0.01), and the △P of the most children decreased in the long-term follow-up.The results of Logistic regression analysis showed that valve dysplasia with right ventricular outflow tract stenosis and the immediate postoperative residual transvalvular gradient degree were the risk factors for long term curative effect of PBPV in children who could not reach the best standard.The restenosis rate was 4.6%(3/65 cases) with children followed up for more than 10 years.The incidence of long-term follow-up pulmonary valve regurgitation (83%) was significantly higher than that before operation (58%) and short term (68%) after operation, and the degree of regurgitation also increased (P<0.05), while the degree of regurgitation of the tricuspid regurgitation decreased gradually during the follow-up (P<0.05); the right ventricular diastolic diameter of the patients at 10 years or more after the operation was measured as (19.27±3.03) mm, which was significantly higher than that (15.24±2.89) mm of the healthy children of at the same term healthy age (P<0.05). Conclusions The PBPV has a high success rate in the treatment of children with PS, and it has good medium-long-term curative effect, less complications and lower restenosis rate.Therefore, PBPV can be used as the first choice for PS.However, the incidence and degree of pulmonary regurgitation has an increasing trend after PBPV and the right ventricular diastolic diameter is still larger than that of the healthy children.Therefore, the long-term follow-up is necessary out of the hospital. Key words: Percutaneous balloon pulmonary valvuloplasty; Pulmonary valve stenosis; Child; Follow-up

Results of pulmonary balloon valvuloplasty persist and improve at late follow-up in isolated pulmonary valve stenosis

Pulmonary balloon valvuloplasty is a safe and effective treatment for children with pulmonary valve stenosis. A few studies evaluate the long-term outcomes of the procedure, particularly the degree of pulmonary regurgitation. We evaluated the outcomes of children >1 year following valvuloplasty for pulmonary valve stenosis. A retrospective analysis of children with pulmonary valve stenosis following pulmonary balloon valvuloplasty at a single institution was performed. Clinic summaries, catheterisation data, and echocardiographic data were reviewed. Inclusion criteria were isolated pulmonary valve stenosis, age <19 years at the time of intervention, and at least one echocardiogram performed at least 1 year after valvuloplasty. A total of 53 patients met inclusion criteria. The median age at valvuloplasty was 0.4 years (0.01-10.6 years). The last follow-up was 4.8±2.3 years following valvuloplasty. The pre-valvuloplasty peak instantaneous gradient by echocardiography was 60.6±14.6 mmHg. The peak gradient at the first postoperative echocardiography was reduced to 25.5±12 mmHg (p<0.001), and further decreased to 14.8±15.8 mmHg (p<0.001) at the most recent follow-up. The degree of regurgitation increased from before valvuloplasty to after valvuloplasty (p<0.001) but did not progress at the most recent follow-up (p=0.17). Only three patients (5.7%) required re-intervention for increasing pulmonary stenosis (two surgical; one repeat balloon). No significant procedural complications occurred. Pulmonary balloon valvuloplasty remains a safe and effective treatment for children with isolated pulmonary valve stenosis, with excellent long-term outcomes and no mortality. A few patients require further intervention. Long-term follow-up demonstrates decreased, residual stenosis. Patients have a small, acute increase in pulmonary regurgitation following valvuloplasty, but no long-term progression.

Earlier Pulmonary Valve Replacement in Down Syndrome Patients Following Tetralogy of Fallot Repair.

The association between Down syndrome and pulmonary hypertension could contribute to more severe pulmonary regurgitation after tetralogy of Fallot repair and possibly earlier pulmonary valve replacement. We compared cardiac magnetic resonance measures of pulmonary regurgitation and right ventricular dilation as well as timing of pulmonary valve replacement between those with and without Down syndrome after tetralogy of Fallot repair. Review of our surgical database from 2000 to 2015 identified patients with tetralogy of Fallot with pulmonary stenosis. Those with Down syndrome were compared to those without. The primary outcome of interest was time from repair to pulmonary valve replacement. Secondary outcomes included pulmonary regurgitation and indexed right ventricular volume on cardiac magnetic resonance imaging. The cohort of 284 patients included 35 (12%) with Down syndrome. Transannular patch repair was performed in 210 (74%). Down syndrome showed greater degree of pulmonary regurgitation (55±14 vs. 37±16%, p=0.01) without a significantly greater rate of right ventricular dilation (p=0.09). In multivariable analysis, Down syndrome (HR 2.3, 95% CI 1.2-4.5, p=0.02) and transannular patch repair (HR 5.5, 95% CI 1.7-17.6, p=0.004) were significant risk factors for valve replacement. Those with Down syndrome had significantly lower freedom from valve replacement (p=0.03). Down syndrome is associated with an increased degree of pulmonary regurgitation and earlier pulmonary valve replacement after tetralogy of Fallot repair. These patients require earlier assessment by cardiac magnetic resonance imaging to determine timing of pulmonary valve replacement and evaluation for and treatment of preventable causes of pulmonary hypertension.

NT-proBNP as Marker of Ventricular Dilatation and Pulmonary Regurgitation After Surgical Correction of Tetralogy of Fallot: A MRI Validation Study.

The goal of this study is to evaluate whether NT-proBNP plasma levels may help as a screening biomarker for monitoring right ventricular dilatation, pulmonary regurgitation and the onset of heart failure in patients with repaired Tetralogy of Fallot. Our single-centre observational prospective study involved 43 patients (15.1years, SD=8) with corrected Tetralogy of Fallot. Data collection included: clinical parameters (electrocardiogram, chest X-ray, NYHA scale, time since last surgery), biochemistry (NT-proBNP levels) and MRI values (ventricular volumetry, pulmonary flow assessment). Mean time since last surgery was 13.5years (SD=7.8). There was a statistically significant correlation between the NT-proBNP levels (187.4pg/ml, SD=154.9) and right ventricular dilatation for both the right ventricular end-diastolic volume (124.9ml/m2, SD=31.2) (Pearson=0.19, p<0.01) and end-systolic volume (56.1ml/m2, SD=18.8) (Pearson=0.21, p<0.01) and also with the pulmonary regurgitation fraction (36.5%, SD=16, Pearson=0.12, p<0.01). No significant correlation was found between NT-proBNP and right ventricular ejection fraction (54.6%, SD=10.6, Pearson=-0.07), left ventricular ejection fraction (59.9%, SD=7.1, Pearson=-0.18) or any clinical parameters. The receiver operating curve analysis evidenced that a NT-proBNP cut-off value above 133.2pg/ml predicted the presence of dilated right ventricular end-diastolic and end-systolic volumes over centile 95 (sensitivity 82 and 83% and specificity 93 and 79%, respectively). In conclusion, in patients with surgically corrected Tetralogy of Fallot, NT-proBNP levels correlate with right ventricular dilatation and the degree of pulmonary regurgitation. Ambulatory determination of NT-proBNP might be an easy, readily available and cost-effective alternative for MRI follow-up evaluation of these patients.

Increased left ventricular myocardial extracellular volume is associated with longer cardiopulmonary bypass times, biventricular enlargement and reduced exercise tolerance in children after repair of Tetralogy of Fallot

BackgroundUnfavorable left ventricular (LV) remodelling may be associated with adverse outcomes after Tetralogy of Fallot (TOF) repair. We sought to assess T1 cardiovascular magnetic resonance (CMR) markers of diffuse LV myocardial fibrosis in children after TOF repair, and associated factors.MethodsIn this prospective, cross-sectional study, native (=non-contrast) T1 times and extracellular volume fraction (ECV) were quantified in the LV myocardium using CMR. Results were related to ventricular volumes and function, degree of pulmonary regurgitation, as well as surgical characteristics, and exercise capacity.ResultsThere was no difference in native T1 times or ECV between 31 TOF patients (age at CMR 13.9 ± 2.4 years, 19 male) and 15 controls (age at CMR 13.4 ± 2.6 years, 7 male). Female TOF patients had higher ECVs than males (25.2 ± 2.9 % versus 22.7 ± 3.3 %, p < 0.05). In the patient group, higher native T1 and ECV correlated with higher Z-Scores of right and left ventricular end-diastolic volumes, but not with reduced left and right ventricular ejection fraction or higher pulmonary regurgitation fraction. Longer cardiopulmonary bypass and aortic cross clamp times at surgery correlated with increased native T1 times and ECVs (r = 0.48, p < 0.05 and r = 0.65, p < 0.01, respectively). Maximum workload (percent of predicted for normal) correlated inversely with ECV (r = -0.62, p < 0.05). Higher native T1 times correlated with worse LV longitudinal (r = 0.50, p < 0.05) and mid short axis circumferential strain (r = 0.38, p < 0.05).ConclusionsAs compared to controls, TOF patients did not express higher markers of diffuse fibrosis. Longer cardiopulmonary bypass and aortic cross clamp times at surgery as well as biventricular enlargement and reduced exercise tolerance are associated with markers of diffuse myocardial fibrosis after TOF repair. Female patients have higher markers of diffuse myocardial fibrosis than males.

Impact of residual right ventricular outflow tract obstruction on biventricular strain and synchrony in patients after repair of tetralogy of Fallot: a cardiac magnetic resonance feature tracking study.

Residual right ventricular outflow tract (RVOT) obstruction (RVOTO) is considered beneficial in patients after repair of tetralogy of Fallot (TOF) although underlying mechanisms are unknown. We sought to elucidate differences in myocardial strain and dyssynchrony parameters in patients after TOF repair with and without residual RVOTO using cardiovascular magnetic resonance (CMR) feature-tracking (CMR-FT) analysis. Fifty-four patients (mean age 16.4 ± 8.4 years) were assessed by CMR 14.2 ± 7.3 years after repair of TOF. Residual RVOTO on echocardiography was defined as a peak systolic RVOT gradient >25 mmHg and was present in 27 patients (no RVOTO in n = 27 patients). Right ventricular (RV) and left ventricular (LV) strain measurements were performed using CMR-FT software. The two groups were well matched for age at CMR scan, time and type of surgical repair. There was no difference in the degree of pulmonary regurgitation (PR) and RV end-diastolic volume. Patients with RVOTO showed significant higher RV circumferential strain (CS) (P = 0.02) and RV radial strain (RS) (P = 0.02) values, whereas RV longitudinal strain (LS) did not differ between the two groups (P = 0.39). The degree of RVOTO showed a significant correlation with RV-CS (r = 0.37; P = 0.006) and RV-RS (r = 0.30; P = 0.03) while RV-LS was unrelated to RVOTO (r = 0.06; P = 0.68). Significant relationships between RV and LV strain parameters were only found in the RVOTO group. Interventricular dyssynchrony was significantly higher in the group without RVOTO (P = 0.03) while LV-LS (P = 0.03) and LV intraventricular synchrony (P = 0.05) were impaired in the RVOTO group. In patients after TOF repair, residual RVOTO seems to preserve RV strain and results in stronger RV-LV interactions and less interventricular dyssynchrony and may therefore possess an early protective effect on RV remodelling. However, the potential negative impact of residual pulmonary stenosis on LV strain and intraventricular synchrony needs further investigation.

Cardiovascular magnetic resonance assessment of aortic root dilatation in adult patients after tetralogy of fallot repair

Purpose: Cardiovascular magnetic resonance (CMR) is an important tool in the follow-up of repaired tetralogy of Fallot (ToF). The dilatation of the aortic root (Ao dil) with risk of aneurysm and dissection is a recognized complication. We aimed to find possible predictors of Ao dil late after ToF repair. Methods: We included patients (pts) aged ≥ 18 years and we measured the maximal absolute diameter of the aortic root at the level of the sinuses of Valsalva (AoD), assessed by CMR, using SSFP cine sequences and angiography. We defined two groups: group 1 - with Ao dil (AoD ≥ 38 mm) and group 2 - without Ao dil (AoD < 38 mm). The CMR protocol included the evaluation of biventricular volumes and systolic function, and degree of pulmonary regurgitation. Exclusion criteria were: Associated heart disease congenital or acquired, genetic syndromes, unrepaired ToF, pregnancy, claustrophobia and contraindications for CMR. Results: We included 53 consecutive pts from March 2011 till December 2012 (mean age 32±10 years; 62% female); 46 pts (87%) were asymptomatic. The mean follow-up time since ToF repair was 23±7 years. In 29 pts (55%) an aortopulmonary (AP) shunt was done prior to complete ToF repair, with a median interval of 3 years. In 17 pts complete repair used a transannular patch. In 10 pts (19%; 9 male) we identified Ao dil. Only 3 out of 10 pts with right aortic arch had Ao dil. Male gender (p<0.0001), older age (39±12 vs 30±9 years; p=0.014), and higher body surface area (BSA 1.92±0.11 vs 1.65±0.19 m2; p<0.0001), left ventricle end-diastolic volume (LVEDV 170±41 vs 124±29 mL; p<0.0001), LVEDV indexed to BSA (LVEDV index 88±19 vs 75±14 mL/m2; p=0.023), left ventricle end-systolic volume (LVESV 76±26 vs 51±17 mL; p=0.022), LVESV indexed to BSA (39±12 vs 31±9 mL/m2; p=0.024) and left ventricle mass indexed to BSA (60±14 vs 52±9 g/m2; p<0.0001) were associated with Ao dil. None of the surgical variables studied (previous AP shunt, transannular patch, time to AP shunt, time between AP shunt and complete repair, time to complete repair) were significantly different between group 1 and 2. In multivariate analysis male gender was the only independent predictor of Ao dil (odds ratio 27.42, 95% confidence interval 1.95-386.48; p=0.014), after adjusting for age, previous AP shunt, follow-up time since ToF surgical repair and for LVEDV index. Conclusions: In this study male gender was the only independent predictor of aortic root dilatation late after ToF repair. In this context, CMR can be used in the screening of pts at risk of late Ao dil and therefore can contribute to prevent its potential complications.

The effects of pregnancy on right ventricular remodeling in women with repaired tetralogy of Fallot

The aim of this study was to better understand the quantitative volumetric changes associated with pregnancy in women with repaired tetralogy of Fallot (TOF), utilizing sequential cardiovascular magnetic resonance (CMR) imaging. An increasing number of women with repaired TOF are reaching childbearing age. Limited echocardiographic studies suggest accelerated remodeling of the right ventricle (RV) in women with repaired TOF after pregnancy. Sequential CMRs from a group of women with repaired TOF who completed pregnancy and from a matched comparison group of nulliparous women with repaired TOF were evaluated. The two groups were matched according to baseline QRS duration, RV end-diastolic volume (EDV), age at CMR and time between CMRs. Longitudinal change of CMR parameters was compared between the groups. Thirteen women (mean age 26.6 ± 7.4 years) with repaired TOF who completed pregnancy and 26 nulliparous women with repaired TOF (mean age 22.6 ± 8.0 years) were included in this analysis. The rate of increase of RV EDV in the pregnancy group was higher than the comparison group (4.1 ± 1.1 ml/m(2)/year vs. 1.6 ± 0.6 ml/m(2)/year, p=0.07). RV EF did not change significantly in either group. No definitive interaction between degree of pulmonary regurgitation and increase of RV EDV was identified. Women with repaired TOF who have completed pregnancy appear to experience an accelerated rate of right ventricular remodeling, defined as an increase in end-diastolic volume; however RV systolic function does not deteriorate. Further investigations with a prospective study design, larger cohorts, and longer follow-up are needed to confirm these initial observations.

Beneficial Effects of Residual Right Ventricular Outflow Tract Obstruction on Right Ventricular Volume and Function in Patients After Repair of Tetralogy of Fallot

Preservation of the pulmonary valve, even at the expense of a mild residual stenosis, is the current surgical policy for the management of patients with tetralogy of Fallot (TOF). This study aimed to assess the long-term effect of a residual right ventricular outflow tract obstruction (RVOTO) on RV dimension and function. This study prospectively assessed 53 children (mean age, 13.4 ± 6.4 years) after repair of TOF using cardiovascular magnetic resonance imaging. Residual RVOTO on echocardiography was defined as a peak systolic RVOT gradient of 25 mmHg or higher. Patients with RVOTO (n = 29) had significantly less pulmonary regurgitation (25.2 ± 10.6 %) than patients without RVOTO (30.8 ± 9.3 %; p = 0.05) (n = 24). Compared with patients who had no RVOTO, children with RVOTO had significantly smaller RV end-diastolic volume (94.0 ± 2.6 vs 104.0 ± 20.7 ml/m(2); p < 0.05) and end-systolic volume (42.9 ± 20.0 vs 48.9 ± 13.2 ml/m(2); p < 0.05), whereas RV ejection fraction did not differ significantly between the two groups (55.5 ± 8.4 vs 54.0 ± 6.6 %). Restrictive physiology, assessed by late diastolic forward flow in the main pulmonary artery, was equally distributed within the two groups (31 vs 25 %; nonsignificant difference). According to the study data, residual RVOTO after repair of TOF does not affect RV function, whereas RV dimensions and the degree of pulmonary regurgitation are more favorable in the long-term follow-up evaluation of those patients. These results confirm the beneficial effects of the current strategy for repair of TOF.

Mid-Term Results of Balloon Pulmonary Valvuloplasty in Children at Queen Alia Heart Institute

Objective: To evaluate the mid-term results of balloon pulmonary valvuloplasty (BPV) in children. Design: Prospective study. Settings: Pediatric Cardiology Department of Queen Alia Heart (QAHI), Jordan. Methods: One hundred and thirty-two patients with a median age of 3 years (range 1 day to 16 years), underwent (BPV) between January 1999 and January 2006. We evaluated our patients with regard to peak pressure gradient across the right ventricular outflow tract before and after BPV. Thereafter we followed them at the Outpatient Clinic regarding the peak instantaneous gradient pressure, the pulmonary valve incompetence, right ventricular function based on echocardiographic findings, and the need for repeat BPV. Results: There was significant reduction in the peak to peak gradient from 93.5 ± 32.3 mmHg to 26.1 ± 9.6 mmHg (p &lt; 0.001). Echo-Doppler data showed that residual peak instantaneous gradient dropped from 26.1 ± 9. 6 to 19 ± 6 mmHg; (p &lt; 0.001) on follow-up for 6 years. Mild to moderarte pulmonary valve regurgitation was noticed in 34 patients (27.8%) at one year and in 43 patients (38%) at mid term follow-up, but non had right ventricular dilatation or paradoxical interventricular septal motion. Conclusions: The results of mid-term follow up after balloon dilatation of the pulmonary valve are encouraging. The degree of pulmonary regurgitation is increasing with time. Longer term follow-up studies should be undertaken to evaluate the significance of residual pulmonary regurgitation.

The influence of pulmonary regurgitation on regional right ventricular function in children after surgical repair of tetralogy of Fallot

Pulmonary regurgitation after repair of tetralogy of Fallot (TOF) results in right ventricular (RV) dysfunction with significant late morbidity and mortality. The aim was to assess the influence of pulmonary regurgitation on regional RV function. In 48 asymptomatic children (age 11.1 +/- 3.3 years) with repair of TOF, peak systolic strain rate (SR) and end-systolic strain (epsilon) were acquired using colour Doppler myocardial imaging. RV indices were quantified by magnetic resonance imaging. Echocardiography and exercise capacity was also performed. Forty complete data sets were analysed. An inverse linear relationship was demonstrated between the degree of pulmonary regurgitation and right ventricle end-systolic epsilon (r = -0.53, P < 0.01) as well as a correlation with peak systolic SR (r = -0.35, P < 0.01). A correlation existed between peak VO(2) and peak systolic SR (r = 0.51, P = 0.001) and end-systolic epsilon (r = 0.33, P < 0.05). In asymptomatic children after repair of TOF, pulmonary regurgitation is associated with impaired regional systolic RV deformation indices. Regional strain and SR may be an early indicator of RV dysfunction in patients with post-TOF and pulmonary regurgitation.

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

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. 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. 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.

Risk factors for early pulmonary valve replacement after valve disruption in congenital pulmonary stenosis and tetralogy of Fallot

Congenital heart defects with a component of pulmonary stenosis are often palliated in childhood by disrupting the pulmonary valve, either by means of dilation or excision. It is unclear what factors affect a patient's ability to tolerate long-term pulmonary insufficiency before requiring pulmonary valve replacement. We analyze potential factors that are related to the interval between pulmonary valve disruption and pulmonary valve replacement. One hundred seven patients were analyzed. They had a congenital diagnosis of pulmonary stenosis or tetralogy of Fallot, had their first pulmonary valve replacement between 2002 and 2008, and had a known interval between pulmonary valve disruption and pulmonary valve replacement. The median age at the time of surgical intervention was 2 years for pulmonary valve disruption (range, 0-56 years) and 26 years for pulmonary valve replacement (range, 1-72 years). The median interval was 23 years (range, 0-51 years). Potential related factors were sex, race, initial diagnosis and procedure, age at pulmonary valve disruption, prior shunt operation, presence of branch pulmonary artery stenosis, and degree of pulmonary regurgitation. As determined by using univariate analysis, male patients had a shorter interval than female patients (median, 16 vs 26 years; P = .01), and African American patients had a shorter interval than white patients (median, 16 vs 25 years; P = .049). A significant correlation was also identified between age at the time of pulmonary valve disruption and the subsequent interval to pulmonary valve replacement. Overall, the interval tended to increase as age at disruption increased (P < .0001). Although the presence of branch pulmonary artery stenosis determined by the need for concomitant pulmonary arterioplasty was associated with a significantly shorter interval to pulmonary valve replacement (21 vs 24 years, P = .02), stenosis determined based on small branch pulmonary artery diameter was correlated to a prolonged interval to pulmonary valve replacement (P = .009). Initial diagnosis, prior palliative shunt operation, and degree of pulmonary regurgitation had no effect on the interval between pulmonary valve disruption and subsequent pulmonary valve replacement. As determined by using multivariate analysis, only male sex and small pulmonary artery diameter remained significant factors. Male sex appears to shorten the interval between pulmonary valve disruption and pulmonary valve replacement, whereas small branch pulmonary artery diameter appears to lengthen the interval. Knowing which factors are detrimental and which are protective might help identify patients who are prone to a more rapid progression of right heart failure from free pulmonary insufficiency, possibly steering them toward more frequent follow-up or more aggressive heart failure medical regimens.

Clinical Summaries

Clinical Summaries

Immunologically Untreated Fresh Xenograft Implantation in a Pig-to-Goat Model

Immunologically untreated frozen-stored xenografts show controlled rejection and repair due to reduced cellularity in our previous study. To clarify the issue, we compared results obtained using fresh and frozen-stored xenografts. Porcine pulmonary valved conduits were prepared without immunologic treatment and implanted in the right ventricular outflow tract of goats under cardiopulmonary bypass immediately after harvest without frozen storage (the fresh group) or after frozen storage (-70 degrees C for 3 - 7 days) (the frozen group). Four goats were assigned to be raised for 3 (N = 1) or 6 (N = 3) months postoperatively in each group. One goat in the frozen group assigned for the 6-month observation expired at 2 months postoperatively because of thrombotic occlusion of the pulmonary valve. The other goats survived until the scheduled sacrifice. According to echocardiographic findings, one animal sacrificed at 3 months in the frozen group showed more than a moderate degree of pulmonary regurgitation, but all animals in the fresh group showed less than a mild degree. On gross examination, leaflets were slightly better preserved in the fresh group and aneurysmal dilatation of the pulmonary artery was observed at 3 months only in the frozen group. Microscopically, pulmonary arteries showed less severe degenerative changes in the fresh group. Moreover, in the fresh group, viable donor valve cells were still present until 3 months postoperatively (though it disappeared at 6 months postoperatively) and a linear endothelial lining of viable host cells was prominent on all leaflets, whereas this was not the case in the frozen group. In conclusion, fresh xenografts preserved cellular viability and showed fewer degenerative changes than frozen-stored xenografts. Thus, immunologically untreated fresh xenografts could provide a potential valve substitute with distinctive advantages in terms of self-healing potential as compared with frozen-stored xenografts.

Comparison of Echocardiographic and Cardiac Magnetic Resonance Imaging for Assessing Right Ventricular Function in Adults With Repaired Tetralogy of Fallot

Adults with repaired tetralogy of Fallot and significant chronic pulmonary regurgitation are at risk for progressive right ventricular (RV) dilatation and dysfunction. The assessment of RV function is important in the management in these patients. There is still a lack of an adequate geometric model to quantify RV function by echocardiography. The myocardial performance index (MPI) is a nonvolumetric method to quantify global ventricular function. In this study, the accuracy of MPI obtained by echocardiography to quantify RV function was assessed in 57 adults with repaired tetralogy of Fallot. The MPI measurement was compared with the RV ejection fraction (EF) derived by cardiac magnetic resonance imaging. There was a negative linear correlation between the MPI and the RVEF (r = 0.73, p <0.001). A MPI cutoff of > or =0.40 had a sensitivity of 81% and a specificity of 85% to diagnose a RVEF <35%. A MPI cutoff of <0.25 had a sensitivity of 70% and a specificity of 89% to identify patients with RVEFs > or =0.50. In a multivariate regression model, the MPI was not affected by the degree of pulmonary regurgitation, the presence of tricuspid regurgitation, or the QRS duration. In conclusion, the Doppler-derived MPI is a simple and reliable method for the evaluation of RV systolic function in adults with repaired tetralogy of Fallot.