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Background and Objective: Assessing the severity of pulmonary regurgitation (PR) and identifying optimal clinically relevant indicators for its treatment is crucial, yet standards for quantifying PR remain unclear in clinical practice. Computational modelling of the heart is in the process of providing valuable insights and information for cardiovascular physiology research. However, the advancements of finite element computational models have not been widely applied to simulate cardiac outputs in patients with PR. Furthermore, a computational model that incorporates both the left ventricle (LV) and right ventricle (RV) can be valuable in assessing the relationship between left and right ventricular morphometry and septal motion in PR patients. To enhance our understanding of the effect of PR on cardiac functions and mechanical behaviour, we developed a human bi-ventricle model to simulate five cases with varying degrees of PR severity., Methods: This bi-ventricle model was built using a patient-specific geometry and a widely used myofibre architecture. The myocardial material properties were described by a hyperelastic passive constitutive law and a modified time-varying elastance active tension model. To simulate realistic cardiac functions and the dysfunction of the pulmonary valve in PR disease cases, open-loop lumped parameter models representing systemic and pulmonary circulatory systems were designed., Results: In the baseline case, pressures in the aorta and main pulmonary artery and ejection fractions of both the LV and RV were within normal physiological ranges reported in the literature. The end-diastolic volume (EDV) of the RV under varying degrees of PR was comparable to the reported cardiac magnetic resonance imaging data. Moreover, RV dilation and interventricular septum motion from the baseline to the PR cases were clearly observed through the long-axis and short-axis views of the bi-ventricle geometry. The RV EDV in the severe PR case increased by 50.3% compared to the baseline case, while the LV EDV decreased by 18.1%. The motion of the interventricular septum was consistent with the literature. Furthermore, ejection fractions of both the LV and RV decreased as PR became severe, with LV ejection fraction decreasing from 60.5% at baseline to 56.3% in the severe case and RV ejection fraction decreasing from 51.8% to 46.8%. Additionally, the average myofibre stress of the RV wall at end-diastole significantly increased due to PR, from 2.7±12.1 kPa at baseline to 10.9±26.5 kPa in the severe case. The average myofibre stress of the LV wall at end-diastole increased from 3.7±18.1 kPa to 4.3±20.3 kPa., Conclusions: This study established a foundation for the computational modelling of PR. The simulated results showed that severe PR leads to reduced cardiac outputs in both the LV and RV, clearly observable septum motion, and a significant increase in the average myofibre stress in the RV wall. These findings demonstrate the potential of the model for further exploration of PR., Competing Interests: Declaration of Competing Interest The authors declare that they have no conflict of interest., (Copyright © 2023 The Author(s). Published by Elsevier B.V. All rights reserved.)

Pulmonary fibroelastomas are a rare primary cardiac tumor with less than 50 cases reported in the literature to date. We performed a minimally invasive valve-sparing tumor resection through a left anterior mini-incision (LAMI). The procedure was performed without cardiac arrest or aortic cross clamp, expediting postoperative recovery and allowing for an uncomplicated discharge on postoperative day 5. LAMI is a safe and reliable alternative to median sternotomy for patients requiring interventions on the right ventricular outflow tract and main pulmonary artery, including pulmonary fibroelastoma resection and pulmonary valve replacement when needed.

Background: We reviewed our revised surgical strategy for tetralogy of Fallot (TOF) total correction to minimize early exposure to significant pulmonary regurgitation (PR) and to avoid right ventriculotomy (RV-tomy). Methods and Results: Since February 2016, we have tried to preserve, first, pulmonary valve (PV) function to minimize PR by extensive commissurotomy with annulus saving; and second, RV infundibular function by avoiding RV-tomy. With this strategy, we performed total correction for 50 consecutive patients with TOF until May 2018. We reviewed the early outcomes of 27 of 50 patients who received follow-up for ≥3 months. Mean patient age at operation was 10.2±5.0 months, and mean body weight was 8.8±1.2 kg. The preoperative pressure gradient at the RV outflow tract and the PV z-score were improved at most recent echocardiography from 82.0±7.1 to 26.8±6.4 mmHg, and from -2.35±0.49 to -0.55±0.54, respectively, during 11.1±1.6 months of follow-up after operation. One patient required re-intervention for residual pulmonary stenosis. Twenty-two patients had less than moderate PR (none, 1; trivial, 8; mild, 13), and 5 patients had moderate PR. There was no free or severe PR., Conclusions: At 1-year follow-up, the patients who underwent total TOF correction with our revised surgical strategy had acceptable results in terms of PV function. The preserved PV had a tendency to grow on short-term follow-up.

Background: Patients with surgically repaired tetralogy of Fallot (rTOF) often have residual pulmonic valve regurgitation, leading to abnormal remodeling and dysfunction of the right ventricle often requiring pulmonic valve replacement. We tested the hypothesis that 3D analysis of right ventricular (RV) shape and function may reveal differences in regional adaptive remodeling that occurs in patients with rTOF, depending on whether a transannular patch (TAP) was utilized., Methods: Forty patients with rTOF who underwent cardiac magnetic resonance imaging (1.5 T), including 20 with and 20 without TAP, and 10 normal controls were studied. Images were analyzed to measure RV endocardial curvature and global and regional volume and function., Results: RV ejection fraction (EF) was 42 ± 11% in TAP and 38 ± 9% in no-TAP (p = 0.19), both lower than 54 ± 3% in controls (p < 0.01). Left ventricular (LV) EF was 54 ± 9% in TAP, 54 ± 8% in no-TAP (p = 0.87) and 61 ± 16% in controls (both p < 0.01). Indexed LV end-diastolic volumes were higher in no-TAP than in TAP subgroup (p = 0.02). With TAP, mid RV septum showed lower curvature during diastole (less convex), than the mid and apical free walls and free wall adjacent to the RV outflow tract (RVOT; more convex). There were no differences in curvature during systole between rTOF subgroups but mid and RVOT free walls showed higher curvature versus controls., Conclusions: This is the first study to comprehensively describe the influence of TAP on changes in regional RV shape in patients with rTOF. Understanding these differences may help guide therapeutic options for residual pulmonary valve regurgitation in rTOF patients., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Aim: Longitudinal ventricular contraction is a parameter of cardiac performance with predictive power. Right ventricular (RV) longitudinal function is impaired in patients with free pulmonary regurgitation (PR) following corrective surgery for Tetralogy of Fallot (TOF). It remains unclear whether this is a consequence of the surgical repair, or whether it is inherent to PR. The aim of this study was to assess the relationship between longitudinal, lateral and septal pumping in a porcine model of isolated PR., Methods: Piglets were divided into a control (n = 8) group and a treatment (n = 12) group, which received a stent in the pulmonary valve orifice, inducing PR. After 2-3 months, animals were subjected to cardiac magnetic resonance imaging. A subset of animals (n = 6) then underwent percutaneous pulmonary valve replacement (PPVR) with follow-up 1 month later. Longitudinal, lateral and septal contributions to stroke volume (SV) were quantified by measuring volumetric displacements from end-diastole to end-systole in the cardiac short axis and long axis., Results: PR resulted in a lower longitudinal contribution to RV stroke volume, compared to controls (60.0 ± 2.6% vs. 73.6 ± 3.8%; P = 0.012). Furthermore, a compensatory increase in septal contribution to RVSV was observed (11.0 ± 1.6% vs. -3.1 ± 1.5%; P < 0.0001). The left ventricle (LV) showed counter-regulation with an increased longitudinal LVSV. Changes in RV longitudinal function were reversed by PPVR., Conclusion: These findings suggest that PR contributes to decreased RV longitudinal function in the absence of scarring from cardiac surgery. Measurement of longitudinal RVSV may aid risk stratification and timing for interventional correction of PR in TOF patients., (© 2017 The Authors. Acta Physiologica published by John Wiley & Sons Ltd on behalf of Scandinavian Physiological Society.)

In patients with carcinoid syndrome, the development of carcinoid valve disease typically carries an unfavorable prognosis. We present the case of a patient with significant valvular dysfunction secondary to carcinoid valve disease. Valve replacement surgery was complicated by the development of prosthetic valve degeneration, ultimately requiring percutaneous valve implantation in a valve-in-valve fashion. The technical details of the case, as well as a review of carcinoid valve disease, including its pathophysiology, clinical manifestations, diagnostic features and management considerations, are presented.

Patients may develop hemodynamic abnormalities after right ventricular outflow tract (RVOT) repair. Re-intervention timing remains a dilemma. This study evaluates exercise capacity and RV function before and after intervention using age-related comparisons. Twenty-six patients with severe pulmonary regurgitation (PR) after initial repair scheduled for pulmonary valve replacement (PVR) were enrolled. Metabolic treadmill testing (EST) and MRI were obtained before and after surgery. EST results were compared with matched controls. Preoperative exercise time and peak oxygen consumption (VO2 max) were significantly diminished compared with controls but were not significantly different postoperatively. The patients were then split into age-related cohorts. When comparing pre-PVR and post-PVR exercise time and VO2 max among themselves, neither cohort showed significant differences. However, patients younger than 25 years had better postoperative results, an age-related difference not seen in the controls. Preoperative MRI showed significantly dilated RV, PR, and low normal function. After PVR, the right to left ventricular end-diastolic volume ratio (RVEDV:LVEDV) and pulmonary artery regurgitant fraction (RF) significantly decreased. There was no change in ventricular ejection fractions (EF). Severe PR, decreased RVEF, and RV dilation can significantly diminish exercise capacity. PVR improves RVEDV:LVEDV and RF, but not EF. Younger patients had better exercise capacity that was maintained postoperatively. This age-related difference was not seen in the controls, indicating that earlier intervention may preserve exercise capacity. Serial ESTs in patients with severe PR following RVOT repair may identify deteriorating exercise capacity as an early indicator for the need for PVR.

Objectives: We examined interventionally implanted valved Melody conduits after surgical explantation by means of histology and immunohistochemistry and matched these findings with clinical data in order to assess in vivo biocompatibility and to identify risk factors for graft failure., Methods: 9 Melody valves had been implanted in 8 patients (pulmonary n = 7, tricuspid position n = 1). Indication for explantation included significant obstruction in 7 patients and valve insufficiency in 1 patient. 4 of 8 patients had suffered from endocarditis. Mean interval between implantation and explantation was 3.2 (1.8-5.2) years. All explants were worked up using a uniform protocol with fixation in formalin and embedding in methylmethacrylate., Results: All but one valve of the explanted Melody grafts were thin and histologically intact without any pathological findings. Complete neo-endothelialization could be demonstrated by means of immunohistochemistry. All 4 Melody valves from patients with endocarditis showed dense granulocytic infiltrations, 3 of these showed thrombotic material within the valves., Conclusion: This report covers the first series of explanted Melody valves from humans applying a uniform protocol for histopathological examination. Good biocompatibility of the Melody valves could be demonstrated after a mid-term follow-up. Factors for graft failure included endocarditis, outgrowth, and residual stenosis. These findings may have significant implications for the implant procedure as well as care of the patients during long-term follow-up., (Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.)

In this review, we discuss right-sided heart valve disease, namely tricuspid regurgitation (TR), tricuspid stenosis, pulmonary regurgitation, pulmonary stenosis and right-sided endocarditis. These are frequently seen in conjunction with other diseases, making assessment of their significance more difficult, but it has become increasingly clear that moderate or severe right-sided heart valve disease, in particular TR, is associated with worse prognosis. There remain large gaps in our knowledge of medical and interventional treatment, but in this article we outline what is known about the causes, presentation and management of these commonly seen conditions., (© 2014 John Wiley & Sons Ltd.)

Pulmonary valve disease constitutes a wide spectrum of conditions. Traditionally, echocardiography has been the technique of choice for the evaluation of pulmonary and other valvular disease. However, with advances in technology, computed tomography (CT) and magnetic resonance imaging (MRI) are playing increasingly important roles in the evaluation of these disorders. In this article, we review the normal appearance of the pulmonary valve and then illustrate various variants and pathological entities of the pulmonary valve., (Copyright © 2014 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.)

Septal systolic motion is towards the left ventricle (LV) in healthy hearts. Patients with pulmonary regurgitation (PR) and right ventricular (RV) volume overload have systolic septal motion toward the RV. This may affect the longitudinal contribution from atrioventricular plane displacement (AVPD) and septal and lateral contribution to stroke volume (SV). The study aimed to quantify these contributions to SV in patients with PR. Cardiac magnetic resonance imaging was used for assessment of cardiac volumes. Patients (n = 30; age 9-59 yr) with PR due to surgically corrected tetralogy of Fallot and 54 healthy controls (age 10-66 yr) were studied. Longitudinal contribution to RVSV was 47 ± 2% (means ± SE) in patients with PR and 79 ± 1% in controls (P < 0.001). Lateral contribution to RVSV and LVSV was 40 ± 1 and 62 ± 2% in patients and 31 ± 1 and 36 ± 1% in controls (P < 0.001 for both). Septal motion contributed to RVSV by 8 ± 1% in patients and by 7 ± 1% to LVSV in controls (P < 0.001). PR patients have decreased longitudinal contribution to RVSV and increased lateral pumping, resulting in larger outer volume changes and septal motion towards the RV. The changes in RV pumping physiology may be explained by RV remodeling resulting in lower systolic inflow of blood into the right atrium in relation to SV. This avoids the development of pendulum volume between the caval veins and right atrium, which would occur in PR patients if longitudinal contribution to SV was preserved. Decreased AVPD suggests that tricuspid annular excursion, a marker of RV function, is less valid in these patients.

Background: Transcatheter pulmonary valve (TPV) replacement is an emerging therapy intended to restore pulmonary valve function in patients with right ventricular outflow tract conduit dysfunction; the impact of this technique on ventricular strain and synchrony is not known., Methods and Results: Cardiac magnetic resonance and ECG data acquired at 1 center as part of the US Melody TPV trial were analyzed. Biventricular strain and mechanical synchrony measurements were made based on short-axis and 4-chamber steady-state free precession images using feature tracking software. Post- versus pre-TPV replacement findings were compared for all patients (n=31) and subgroups with predominant pulmonary regurgitation (n=13) or stenosis (n=18). Most patients had tetralogy of Fallot (18/31). After TPV replacement, left ventricular (LV) circumferential strain increased for the whole cohort (P<0.001) and both subgroups (pulmonary regurgitation P=0.01; pulmonary stenosis P=0.02). LV longitudinal strain increased for the whole cohort (P=0.02) and pulmonary regurgitation subgroup (P=0.05); circumferential right ventricular strain increased for the pulmonary stenosis group only (P=0.05). LV longitudinal synchrony improved significantly in the pulmonary regurgitation group (maximum wall delay P=0.03; cross-correlation delay P=0.01). Electric measures of synchrony did not improve., Conclusions: In patients with right ventricular outflow tract conduit dysfunction, TPV replacement is associated with improved global LV strain, as well as improved right ventricular strain and LV synchrony in subgroups. Given the associations between strain and synchrony and clinical outcomes, these findings support potential long-term benefits of TPV replacement.

Clinical/methodical Issue: Right ventricular outflow tract (RVOT) dysfunction with pulmonary regurgitation or obstruction is a common postsurgical consequence in congenital heart disease., Standard Radiological Methods: Magnetic resonance imaging (MRI) is widely accepted as standard method of imaging in congenital heart disease. It provides anatomical and functional information without radiation exposure and is therefore well suited for serial examinations., Methodical Innovations: Percutaneous pulmonary valve implantation (PPVI) has been shown to be a safe and effective treatment option for patients with pulmonary valve insufficiency or stenosis. Correct patient selection for PPVI is crucial. It is important to be familiar with the indications and anatomical requirements for stent placement and to tailor imaging protocols., Performance: Imaging the RVOT, assessment of right ventricular volumes and function and calculation of pulmonary flow and regurgitation are core elements of the MRI examination prior to PPVI. Low interobserver and intraobserver variation allows even small changes to be detected., Achievements: Imaging provides relevant information for correct patient selection for PPVI and is part of postinterventional follow-up. Imaging is an important tool for documentation of success and for detection of complications., Practical Recommendations: Several imaging modalities are used for evaluation of RVOTs; however, MRI can provide answers to most questions without radiation exposure.

Objective: Tetralogy of Fallot (TOF) is the most common form of cyanotic congenital heart disease. Today, we are faced with an increasing number of patients with residual pulmonary regurgitation (PR) late after TOF repair. The right ventricular (RV) volumes and function are among the most important factors influencing clinical decision-making. Cardiac magnetic resonance (CMR) is the gold standard method for the quantitative assessment of the RV function; it is, however, expensive for routine clinical follow-up and sometimes is contraindicated. We sought to evaluate the RV systolic function via CMR and compare it with Doppler-derived strain(S) and strain rate (SR) imaging in patients with repaired TOF., Methods: In an observational cross-sectional study, 70 patients (22 women, mean age=22±4.9 years) late after TOF repair with severe PR were evaluated. Peak systolic strain and SR in the basal, mid, and apical segments of RV free wall (RVFW) were measured and compared with the RV function measured in the short-axis cine MR. Associations between RVEF and S/SR, investigated by ordinal logistic regression models., Results: Significant association was observed between RV function and mean S of all the three segments of the RVFW segments [OR (CI95%): 1.17 (1.05-1.31)]. Association between RV function and mean SR of all the three segments of the RVFW segments was borderline significant [OR (CI95%): 1.7 (0.97-2.93)]., Conclusion: There was a significant correlation between the Doppler-derived mean strain of RVFW and the RV function measured by CMR in adults late after TOF repair. These quantitative methods improved the assessment of the RV function and served as an additional method to follow up patients with contraindications to CMR.

Background: Patients may suffer from right ventricular (RV) failure and malignant cardiac arrhythmias after late pulmonary valve replacement correcting pulmonary regurgitation (PR). But the underlying mechanisms of the refractory arrhythmias are not well understood., Methods: The aim of present study was to characterize the RV myocardium after percutaneous pulmonary valve implantation (PPVI) in a porcine model after severe PR for 3months. RV histology was evaluated with morphometric methods and RV function was assessed with electrophysiology, echocardiography, and biochemical measures: The results were compared with age-matched sham-operated animals., Results: At euthanasia, RV weight was increased compared to sham-animals, median 127 g (115-137) vs. 71 g (69.5-76.5), p=0.0007. RV myocyte diameters corrected for individual variation with the RV/LV ratio were enlarged, 1.06 (1.02-1.13) vs. 0.84 (0.80-0.91), p=0.0006. There were no excess collagen tissue (RV/LV ratio), p=0.77. Electrophysiological stimulation resulted in RV arrhythmia in 67% of the animals compared to 25% in the sham-operated animals, but this difference was not statistically significant, p=0.28. Echocardiography revealed geometrical dilation in end-systolic RV area, mean ± SD, 11.8 ± 4.9 cm(2) vs. 6.0 ± 3.5 cm(2), p=0.05, and end-diastolic area, 23.3 ± 10.4 cm(2) vs. 12.7 ± 2.5 cm(2), p=0.08. RV anterior free wall thickness was not increased, 0.7 ± 0.2 cm vs. 0.7 ± 0.1 cm, p=0.66. Echocardiographic functional parameters and plasma natriuretic peptides were unchanged., Conclusions: The RV does not completely recover after three months of PR with persistent myocardial hypertrophy one month after PPVI. Future studies should address whether RV chamber and cellular hypertrophy, without fibrosis or interventional scar tissue, may be substrate for arrhythmia., (Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.)

Aims: To validate patient-specific computational testing of a second-generation device for percutaneous pulmonary valve implantation (PPVI), against realistic in vitro data., Methods and Results: Tests were initially carried out in a simple loading mode, performing a compliance test on a rapid prototyped cylinder. This model was reproduced computationally and validated against the experimental data. A second-generation PPVI stent-graft, with no valve mounted, was then deployed in a simplified cylindrical geometry, measuring its displacement when subjected to a pressure pulse. Experimental and computational measurements were in good agreement. Finally, having selected a patient regarded as unsuitable for first-generation PPVI, but potentially suitable for a second-generation device, the stent-graft was studied in the rapidly prototyped patient-specific right ventricular outflow tract (RVOT). Stent positioning and radial displacements with pulsatile flow were observed in a mock circuit using fluoroscopy imaging. Stent deformation and anchoring were measured both in vitro and computationally. Both tests indicated that the stent was well anchored in the RVOT, especially in the distal position, and its central region was rounded, ensuring, were a valve present, optimal valve function., Conclusion: We suggest that an experimentally validated computational model can be used for preclinical device characterisation and patient selection.

Objectives: In patients with corrected Tetralogy of Fallot (cToF), pulmonary regurgitation and subsequent increased right ventricular (RV) end-diastolic volume are diastolic parameters related to adverse outcome. In addition, abnormalities of the RV outflow tract (RVOT) independently promote RV dilatation in cToF patients. Tissue Doppler imaging (TDI) and tissue-velocity magnetic resonance imaging (TV-MRI) enable quantitative assessment of regional diastolic performance by measuring myocardial velocities. Assessment of regional diastolic velocities of the RV may provide insight into the relation between RVOT dysfunction and RV dilatation in cToF patients. The aim of the study was to perform a direct comparison of TV-MRI against TDI to assess regional RV diastolic velocities in cToF patients and control subjects. In addition, the relationship between regional RV diastolic velocities and RV dilatation was investigated., Materials and Methods: Thirty-four cToF patients (8-18 years) and 19 controls were studied. Early (E') and late (A') peak diastolic velocities and E'/A' ratio were assessed with TDI and TV-MRI at the RV free wall and at the RVOT. RV volumes and pulmonary regurgitation were quantified with planimetric and 3-dimensional flow MRI, respectively., Results: Good correlation and agreement were observed between TDI and TV-MRI at both regions of the RV (RV free wall: E': r = 0.92, mean bias: 0.5 cm/s, A': r = 0.92, mean bias: 0.4 cm/s; RVOT: E': r = 0.92, mean bias: -0.3 cm/s, A': r = 0.95, mean bias: 0.03 cm/s). With both imaging techniques, regional RV diastolic velocities were significantly reduced in cToF patients. The E'/A' ratio at the RVOT (assessed with both TDI and TV-MRI) was related to RV end-diastolic volume, even after correction for pulmonary regurgitation (TDI: P < 0.01, TV-MRI: P = 0.05)., Conclusions: TDI and TV-MRI can be used interchangeably for the assessment of regional diastolic velocities and performance of the RV in cToF patients and in healthy controls. Regional diastolic velocities at the RVOT are reduced in cToF patients as compared with controls. In addition to pulmonary regurgitation, impaired diastolic performance at the RVOT is independently related to RV dilatation.

Background and Aim of the Study: The treatment of pulmonary insufficiency (PI) following reconstructive surgery of the right ventricular outflow tract (RVOT) in repair of the tetralogy of Fallot remains a significant challenge. The study aim was to establish an ovine model of dilated RVOT and PI, and to quantify the degree of PI and right ventricular remodeling over an eight-week period, using magnetic resonance imaging (MRI)., Methods: Five sheep underwent baseline MRI scanning and catheterization. The weight-indexed right and left ventricular end-diastolic volume (EDV), end-systolic volume (ESV), stroke volume (SV), ejection fraction (EF) and pulmonary regurgitant fraction (RF) were measured at baseline. The animals then underwent pulmonary valvectomy and transannular patch repair of the RVOT. Repeat MRI and hemodynamic measurements were obtained after an eight-week period., Results: The indexed RVEDV increased from 49 +/- 4.0 ml/m2 at baseline to 80 +/- 10.3 ml/m2 at eight weeks after valvectomy (p = 0.01), while the indexed RVESV increased from 13 +/- 3.4 ml/m2 to 33 +/- 8.8 ml/m2 (p = 0.01). The indexed RVSV increased from 36 +/- 3.7 ml/m2 to 47 +/- 1.7 ml/m2 (p = 0.01). The RVEF at baseline was 74 +/- 6%, and this decreased to 59 +/- 5% at follow up (p = 0.02). The RF at baseline was 0 +/- 0% and was increased to 37 +/- 3% at eight weeks after valvectomy (p < 0.001). The left ventricular (LV) function was also diminished: LVEF at baseline was 67 +/- 2%, versus 49 +/- 10% at follow up (p = 0.01). Both, the RV and LV end-diastolic pressures were significantly elevated at follow up., Conclusion: All five animals developed pulmonary regurgitation sufficient to cause significant RV dilatation and diminished RV and LV functions. This model may be used to investigate novel therapeutic approaches in the treatment of this difficult clinical problem.

Given late outcomes of patients with tetralogy of Fallot repaired in the 1970s and 1980s, as well as a better understanding of the late deleterious effects of pulmonary regurgitation, there is a tendency toward preservation of the pulmonary valve function during primary repair of tetralogy of Fallot. The bar keeps moving downward, to include smaller and more dysmorphic pulmonary valves. This article reviews some useful indications and techniques for valve-sparing options, including intraoperative balloon dilation and cusp reconstruction using a patch. Just like other valve repair techniques, no one technique can be applied uniformly, and surgeons must master a wide armamentarium of techniques., (Copyright © 2012 Elsevier Inc. All rights reserved.)

The pulmonary valve consists of 3 leaflets and is similar in anatomy to the aortic valve. It is the least likely to be affected by acquired disease, and thus, most disorders affecting it are congenital. The most common hemodynamic abnormality of the pulmonary valve is the congenitally narrowed domed valve of pulmonic stenosis. Pulmonary stenosis is usually well tolerated in its mild and moderate forms. This article discusses the clinical evaluation, cardiac catheterization, and echocardiography of pulmonary stenosis and pulmonary regurgitation.

Objective: This study aimed to compare the results of angiocardiography and cardiovascular magnetic resonance imaging in the assessment of pulmonary regurgitation following repair of tetralogy of Fallot., Methods: We prospectively studied 37 patients with repaired tetralogy of Fallot. After routine examination cardiovascular magnetic resonance imaging (CMR) and cardiac catheterization and angiography were performed. Pulmonary regurgitation (PR) was classified according to the following criteria, using a left lateral angiogram of the main pulmonary artery; insufficiency jet is limited to right ventricular outflow tract (mild); jet reaches the body of right ventricle (moderate); jet fills the apex of the right ventricle (severe)., Results: Pulmonary regurgitation determined by angiocardiography and CMR was severe in 51.4% and 32.4%, moderate in 27% and 40.5%, and none or mild in 21.6% and 27% of patients respectively. The ability of semi-quantitative estimation of PR determined by cardiac catheterization to distinguish between mild, moderate and severe pulmonary regurgitation was shown to have significant correlation with pulmonary regurgitant fraction obtained by CMR., Conclusions: Angiography obtained during invasive study can be used for the diagnosis and follow-up of pulmonary regurgitation confidently in patients with repaired tetralogy of Fallot and residual pulmonary regurgitation.

Isolated absent pulmonary valve syndrome is a very rare entity. We report the case of a four-year-old boy who had congenital absent pulmonary valve with a thin and aneurysmal right ventricular infundibulum. The histological picture was suggestive of Uhl's anomaly. This association of partial right ventricular Uhl's anomaly with absent pulmonary valve syndrome has not been described before. We discuss the embryological and clinical significance of this association.

The right ventricle (RV) tolerates acute pulmonary valvular regurgitation fairly well, however, in the long-term dilatation and failure often ensues. There is little known of the structural and functional myocardial alterations following this pathophysiology, and therefore animal models are sought. We aimed to develop an animal experimental model for RV dilatation emphasizing feasibility, reproducibility and human compatibility. Free pulmonary valve insufficiency and RV dilatation were created with a novel external suture plication technique in nine 5 kg piglets. Six matched animals served as controls. After 10 weeks cardiac dimensions and physiology were assessed with in vivo cardiovascular MRI and conductance technique. RV end-diastolic volume increased 31% in the intervention group (P=0.03). The regurgitation fraction was 37% in the intervention group compared to -2% in controls (P<0.001). Conductance measurements showed preserved RV contractile function, but significant left ventricular diastolic impairment. This study is the first to show that pulmonary valve regurgitation, RV dilatation and functional impairment can be achieved by external leaflet plication. Compared to known methods, the advantages of this model are: 1) no induction of stenosis over time, 2) no risk of stent migration, and 3) very simple and reproducible.

Around 75% of patients with severe pulmonary insufficiency requiring valvular replacement are excluded from percutaneous pulmonary valve implantation (PPVI) due to a large ventricular outflow tract. To extend the indication of PPVI to these patients, a new size reducer has been designed. This 35-mm size reducer was successfully deployed inside the main pulmonary artery through a 21-Fr delivery catheter in six sheep. A 20-mm pericardial valved stent was subsequently deployed inside the size reducer to restore pulmonary valve continence. We successfully verified the efficiency of the delivery catheter by controlling the deployment precisely and reversibly. In all six cases, device positioning was satisfactory. There was no post-procedural residual stenosis in the right ventricular outflow tract in haemodynamic (9.5+/-3 mm Hg), echocardiographic and angiographic studies. After 8-12 weeks of follow-up, no prosthetic migration occurred. The transprosthetic systolic gradient remained low (4+/-2.5 mm Hg) during follow-up. There was one trivial persistent paraprosthetic leak. This study confirmed the feasibility and the effectiveness of this new size reducer to reduce the size of the pulmonary artery., (Copyright (c) 2009 European Association for Cardio-Thoracic Surgery. Published by Elsevier B.V. All rights reserved.)

The data describing the change in exercise capacity after surgical or interventional management of the patient with right ventricular (RV) outflow tract (OT) dysfunction are conflicting. The pathophysiologic consequences of RVOT interventions and the subsequent change in exercise performance are still poorly understood. We sought to assess the effect of percutaneous pulmonary valve implantation (PPVI) on exercise capacity in (1) patients with predominantly pulmonary stenosis (PS) and (2) in patients with predominantly pulmonary regurgitation (PR). A total of 63 patients with either predominantly PS (n = 37) or PR (n = 26) underwent PPVI. Cardiopulmonary exercise testing and magnetic resonance imaging were performed before and within 1 month after PPVI. On magnetic resonance imaging, the at rest effective biventricular stroke volumes improved in both groups after PPVI (p <0.001), but the ejection fraction improved only in the PS group. In the PS group, exercise capacity (peak oxygen uptake, p <0.001), ventilatory efficiency (p <0.001), and peak oxygen pulse (p <0.001) improved after PPVI. In the PR group, none of these parameters changed after PPVI (p = 0.6, p = 0.12, and p = 0.9, respectively). On multivariate analysis, the reduction in RVOT gradient was the only predictor of improved peak oxygen uptake when assessed in the whole patient group (r(part) = -0.59; p <0.001) or in the PS (r(part) = -0.45; p = 0.002) or PR groups alone (r(part) = -0.45; p = 0.02). In conclusion, acutely after PPVI, exercise capacity improves with the relief of stenosis but not regurgitation. A reduction in the RVOT gradient, even small gradients, was the only independent predictor of improved peak oxygen uptake in both patient groups, irrespective of improved pulmonary valve competence., (Copyright 2010 Elsevier Inc. All rights reserved.)

In this report, we present our experience with successful pulmonary valve repair for pulmonary regurgitation in a 15-year-old patient who had undergone percutaneous pulmonary balloon valvuloplasty for pulmonary stenosis in the neonatal period. The pathological findings and the technique of repair are described in detail as the number of such patients is expected to increase in future.

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.

Objective: 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., Methods: 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., Results: 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., Conclusions: 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.

Background: Treatment of right ventricular outflow tract obstruction is possible with a bare metal stent (BMS), although this treatment causes pulmonary regurgitation. In this study, we assessed the acute physiological effects of BMS versus percutaneous pulmonary valve implantation (PPVI) using an x-ray/magnetic resonance hybrid laboratory., Methods and Results: Fourteen consecutive children (median age, 12.9 years) with significant right ventricular outflow tract obstruction underwent BMS followed by PPVI. Magnetic resonance imaging (ventricular volumes and function and great vessel blood flow) and hemodynamic assessment (invasive pressure measurements) were performed before BMS, after BMS, and after PPVI; all were performed under general anesthesia in an x-ray/magnetic resonance hybrid laboratory. BMS significantly reduced the ratio of right ventricular to systemic pressure (0.75+/-0.17% versus 0.41+/-0.14%; P<0.001) with no further change after PPVI (0.42+/-0.11; P=1.0). However, BMS resulted in free pulmonary regurgitation (21.3+/-10.7% versus 41.4+/-7.5%; P<0.001), which was nearly abolished after PPVI (3.6+/-5.6%; P<0.001). Effective right ventricular stroke volume (right ventricular stroke volume minus pulmonary regurgitant volume) after BMS remained unchanged (33.8+/-7.3 versus 32.6+/-8.7 mL/m2; P=1.0) but was significantly increased after revalvulation with PPVI (41.0+/-8.0 mL/m2; P=0.004). These improvements after PPVI were accompanied by a significant heart rate reduction (75.5+/-17.7 bpm after BMS versus 69.0+/-16.9 bpm after PPVI; P=0.006) at maintained cardiac output (2.5+/-0.5 versus 2.4+/-0.5 versus 2.7+/-0.5 mL x min(-1) x m(-2); P=0.14)., Conclusions: Using an x-ray/magnetic resonance hybrid laboratory, we have demonstrated the superior acute hemodynamic effects of PPVI over BMS in patients with right ventricular outflow tract obstruction.

Background: In patients with percutaneous device implantation for closure of patent foramen ovale (PFO), a 10% incidence of new or worsened aortic regurgitation within 12 months has been reported with echocardiography. Cardiac magnetic resonance imaging is a powerful noninvasive tool to quantify volume and fraction of valve insufficiencies. We studied the acute and long-term impact of percutaneous device implantation for PFO closure on valve insufficiencies in cardiac magnetic resonance imaging., Methods and Results: Sequential cardiac magnetic resonance imaging studies were performed in 102 patients with cryptogenic ischemic events. Cardiac magnetic resonance imaging was performed before PFO closure, the day after device implantation, and at 12 months of follow-up. There was no difference in volumetric and hemodynamic parameters before PFO closure compared with 12 months of follow-up. With a cutoff for relevant regurgitation fraction of 5%, there were no statistically significant differences in regurgitation fraction of the semilunar and atrioventricular valves. The median fraction of aortic valve insufficiency was 3.9% (interquartile range [IQR] 2.0% to 5.1%) before PFO closure, 5.4% (IQR 4.1% to 5.9%) after device implantation, and 4.3% (IQR 3.3% to 6.0%) at 12 months of follow-up. The size and type of the occluder had no impact on aortic valve insufficiency. Median regurgitation fraction for the pulmonary valve was 3.6% (IQR 2.4% to 6.7%) before intervention, 7.3% (IQR 5.1% to 8.2%) after occluder implantation and 5.8% (IQR 4.8% to 7.4%) at 12 months of follow-up. Values for the mitral valve were 3.1% (IQR 1.4% to 6.0%), 5.5% (IQR 3.5% to 7.3%), and 3.8% (IQR 1.5% to 7.9%) and for the tricuspid valve were 5.4% (IQR 0.1% to 8.8%), 5.8% (IQR 1.4% to 9.2%), and 6.0% (IQR 1.1% to 8.4%), respectively., Conclusions: Percutaneous PFO closure with device implantation has no impact on valve insufficiencies as determined by cardiac magnetic resonance imaging.

Percutaneous pulmonary valve implantation helps in prolonging the lifespan of surgically placed right ventricle-to-pulmonary artery (RV-PA) conduits, and represents a less invasive alternative to repeat open-heart surgery. The clinical indications for treatment match those of surgery. As far as the suitability is concerned, the current ideal substrate is a degenerated RV-PA conduit, because of the presence of a certain degree of calcification that offers a safe anchoring point. So far, patients have been treated with low morbidity and mortality that were further improved with increasing experience. After percutaneous pulmonary valve implantation, patients experience a subjective improvement, mirrored by an objective increase of measured exercise capacity parameters and by reduced RV-PA gradient, regurgitant fraction, and RV volumes. New developments in the experimental field should result in an extension of indications in the future.

Aging is associated with morphologic and functional alterations of the rat's left ventricle. However, the time-course of valvular function and morphology in normal aging rats has not yet been studied. For this purpose, 30 male Wistar rats (318 +/- 5g, 10 weeks old) underwent serial echocardiograms for 58 weeks under sodium pentobarbital 50 mg/kg IP anesthetization followed by necropsy. Histopathology was also performed in two additional groups of 10 rats at 10 and 30 weeks of age. Regurgitations were considered as any retrograde flow on 2-D or M-mode color Doppler echocardiography. Tricuspid regurgitation was already found at 10 weeks of age and became more frequent with age. Pulmonary, mitral and aortic regurgitation was seldom observed at 10 weeks but became more frequent after 30 weeks. For the mitral and aortic valve, this was also associated with an increase in valvular thickness because of nodular or segmental myxoid leaflet changes. The severity of valvular regurgitations did not increase with age. In conclusion, aging leads to morphologic and functional valvular changes in normal rats. This is important when investigating models of valvular heart disease in small animals.

Impairment of right ventricular functions, especially due to chronic pulmonary regurgitation (PR), is a well-known entity in patients with tetralogy of Fallot (ToF) after repair. The aim of this study was to examine the relation between B-type natriuretic peptide (BNP) levels and right ventricular dysfunction by cardiopulmonary exercise test (ET) in patients after repair of ToF. Twenty-five patients with a mean age of 14.1 +/- 4.4 years at follow-up who underwent repair of ToF at a mean age of 4.9 +/- 5.1 years and 29 age- and sex-matched healthy children at a mean age of 13.1 +/- 2.8 years were enrolled in this study. Plasma BNP levels were measured at baseline and at maximal exercise. The volume of right ventricle (RV) and the degree of PR were assessed by two-dimensional echocardiography and color Doppler. Plasma BNP levels were significantly higher in patients with ToF than in controls (28.3 +/- 24.1 vs 7.4 +/- 2.3 pg/mL, p = 0.0001). Exercise was associated with increased plasma BNP levels in both groups. A greater increase in BNP was noted in patients with ToF than in controls (37.6 +/- 27.5 vs 11.3 +/- 4.5 pg/mL, p = 0.0001). Forced vital capacity (FVC%) (84.9 +/- 16.9 vs 98.4 +/- 18.2, p = 0.01) and forced expiratory volume during the 1st second (FEV1%) (91.5 +/- 19.3 vs 103.8 +/- 16.1, p = 0.02) were decreased, exercise duration (ED) (10.1 +/- 1.9 vs 11.4 +/- 1.7 min, p = 0.02), maximum heart rate (HRmax) (171.2 +/- 18.9 vs 186.4 +/- 13.9 /min, p = 0.004), and maximum oxygen uptake (VO(2)max) (1.56 +/- 0.53 vs 2.1 +/- 0.6 L/min, p = 0.007) were lower in patients with ToF. There were significant correlations between the degree of PR and ED (r =-0.3, p = 0.009), HRmax (r =-0.4, p = 0.001), and VO(2)max (r =-0.4, p = 0.001). The correlations were significant both before and after exercise, being more pronounced after exercise between BNP level and the degree of PR (r = 0.6, p = 0.0001). As a result, the severity of PR has a negative influence on right ventricular functions and there is significant relation between right ventricular functions and exercise capacity after repair of tetralogy of Fallot.

We report the morphological changes in a patient with combined pulmonary autograft and homograft dysfunction after 9 years of implantation. The case highlights long-term adaptive changes in the autograft to withstand systemic blood pressure with formation of exuberant pannus rich in elastic tissue. In the homograft, maturation of pannus had produced shortening of the 3 cusps with resultant incompetence.

Aims: To investigate the early clinical and physiological consequences of relieving chronic right ventricular (RV) volume overload with percutaneous pulmonary valve implantation (PPVI)., Methods and Results: We selected 17 patients (age 21.2 +/- 8.7 years), from a total of 125 who underwent PPVI, because they had important pulmonary regurgitation (PR) [regurgitant fraction > 25% on magnetic resonance (MR)] and an echocardiographic gradient < 50 mmHg across the RV outflow tract. Cardiopulmonary exercise testing, tissue Doppler and MR were performed before and within 3 months of PPVI. Following PPVI, PR (40.7 +/- 7.3 to 4.1 +/- 6.1%, P < 0.001) and RV end-diastolic volume fell (115.4 +/- 33.1 to 98.9 +/- 32.0 mL/m(2), P = 0.001); effective RV stroke volume increased (34.3 +/- 7.8 to 44.4 +/- 9.3 mL/m(2), P < 0.001). Left ventricular end-diastolic volume (66.6 +/- 18.0 to 73.4 +/- 16.5 mL/m(2), P = 0.014), stroke volume (38.4 +/- 11.1 to 46.4 +/- 10.2 mL/m(2), P = 0.001) and ejection fraction (57.8 +/- 8.1 to 63.5 +/- 5.2 mL/m(2), P = 0.001) increased. Pulmonary artery diastolic pressure (8.9 +/- 4.5 to 12.5 +/- 5.2 mmHg, P = 0.041) and mitral E/Ea increased (from 9.0 +/- 2.0 to 11.6 +/- 3.1, P = 0.003). Patients felt better, but standard measures of exercise capacity were unchanged., Conclusion: PPVI relieves PR and restores compensatory cardiac performance. The lack of improvement in exercise parameters suggests that, in contrast to pressure overload, the contractile reserve of chronically volume-overloaded myocardium is limited.

Background: To facilitate the optimal timing of pulmonary valve replacement, we analyzed preoperative thresholds of right ventricular (RV) volumes above which no decrease or normalization of RV size takes place after surgery., Methods and Results: Between 1993 and 2006, 71 adult patients with corrected tetralogy of Fallot underwent pulmonary valve replacement in a nationwide, prospective follow-up study. Patients were evaluated with cardiovascular magnetic resonance both preoperatively and postoperatively. Changes in RV volumes were expressed as relative change from baseline. RV volumes decreased with a mean of 28%. RV ejection fraction did not change significantly after surgery (from 42+/-10% to 43+/-10%; P=0.34). Concomitant RV outflow tract reduction resulted in a 25% larger decrease of RV volumes. After correction for surgical RV outflow tract reduction, higher preoperative RV volumes (mL/m2) were independently associated with a larger decrease of RV volumes (RV end-diastolic volume: beta=0.41; P<0.001). Receiver operating characteristic analysis revealed a cutoff value of 160 mL/m2 for normalization of RV end-diastolic volume or 82 mL/m2 for RV end-systolic volume., Conclusions: Overall, we could not find a threshold above which RV volumes did not decrease after surgery. Preoperative RV volumes were independently associated with RV remodeling and also when corrected for a surgical reduction of the RV outflow tract. However, normalization could be achieved when preoperative RV end-diastolic volume was <160 mL/m2 or RV end-systolic volume was <82 mL/m2.

Background: Sepsis often results in severe pulmonary dysfunction. Via the thoracic duct, the lung is the first organ exposed to gut-derived inflammatory mediators released into mesenteric lymph during sepsis., Aim: To investigate whether an enteral immunonutrition during sepsis improves pulmonary function., Methods: Mesenteric lymph was obtained from lymph fistula donor rats after intra peritoneal (i.p.) saline (control lymph) or lipopolysaccharide (sepsis lymph) injection. Sepsis lymph was also collected during enteral immunonutrition with omega-3 enriched, long-chain fatty acids (SMOF lipid). Control, sepsis, or sepsis-SMOF lymph was reinfused into the jugular vein of separate recipient rats. The lungs were then harvested, stained with hematoxylin-eosin, and analyzed for: (1) perpendicular parenchyma thickness of the alveolar wall; (2) myeloperoxidase-positive cells; and (3) terminal deoxynucleotidyl transferase Biotin-dUTP nick end labeling (TUNEL)-positive cells., Results: Enteral immunonutrition during sepsis reduced the release of TNFalpha into mesenteric lymph by about 4.5-fold within the first 2 h. Infusion of sepsis lymph into recipient rats induced thickening of alveolar walls, inflammatory reaction, and apoptosis. Infusion of sepsis lymph obtained during enteral immunonutrition did not cause anatomical changes, induced only a mild inflammatory reaction, and prevented apoptosis in the lungs of recipient rats., Conclusions: Mediators in sepsis lymph induce pulmonary dysfunction such as an increased distance for oxygen transport, inflammatory reaction, and apoptosis. The lung may be protected by an enteral immunonutrition containing long-chain fatty acids.

We present a 22 year old Moroccan woman with chronic severe pulmonary regurgitation, who becomes symptomatic in her fourth month of pregnancy. Cardiovascular magnetic resonance, during pregnancy, revealed a large pulmonary aneurysm and turbulent blood flow in the pulmonary trunk with severe pulmonary regurgitation. After gestation, the branch pulmonary arteries were assessed with magnetic resonance angiography and the severely dilated pulmonary arterial trunk and valve were replaced by a pulmonary homograft. We briefly review this rare syndrome, the management of pulmonary regurgitation during pregnancy and the role of CMR during pregnancy.

Background: Patients with repaired tetralogy of Fallot (ToF) featuring severe pulmonary regurgitation (PR) and/or right ventricular (RV) dysfunction have reduced exercise tolerance., Aims: To assess the impact of PR and of RV function on the ability to recover from exercise in ToF patients., Methods: 61 consecutive patients aged 23.1+/-12.1 years underwent maximal cardiopulmonary exercise test (CPX), transthoracic echocardiography and magnetic resonance imaging. This data was compared to those of 153 matched healthy subjects., Results: 19 patients (31%) had severe PR. RV dysfunction was noted in 19 patients (31%). Nine patients (15%) had both severe PR and RV dysfunction. Patients had lower peak oxygen uptake (VO2), VO2 slope, carbon dioxide production (VCO2) slope and O2 pulse slope (p < 0.0001), especially those with severe PR and RV dysfunction (p < 0.0001). Heart rate slope was similar between groups. No patient with severe PR and RV dysfunction had a predicted peak VO2 > 40%. CPX had a high sensitivity and specificity to identify patients with severe PR and RV dysfunction., Conclusions: In ToF patients, severe PR and RV dysfunction lead to delayed recovery from exercise. CPX can identify patients with severe PR and RV dysfunction and may be useful to guide the pulmonary valve replacement decision-making process.

Background: Cardiac volumetry by magnetic resonance imaging can guide the timing for reoperation in minimally symptomatic or asymptomatic patients with pulmonary insufficiency after corrected tetralogy of Fallot. Pro-brain natriuretic peptide (BNP) is a marker of ventricular dysfunction and wall stress, and levels may complement magnetic resonance imaging in cardiac assessment before and after pulmonary valve replacement., Methods: Between May 2004 and October 2005, 23 consecutive patients with corrected tetralogy, severe pulmonary insufficiency, and right ventricular end-diastolic volume index greater than 150 mL/m2 underwent elective pulmonary valve replacement. Plasma proBNP levels and magnetic resonance imaging were obtained before and 6 months after pulmonary valve replacement., Results: There was no surgical mortality or morbidity. Preoperative right ventricular end-diastolic volume index correlated with pulmonary insufficiency, and inversely so with left ventricular ejection fraction, reflecting interventricular interaction. Preoperatively (r = -0.47) and 6 months postoperatively (r = -0.54), log BNP was inversely correlated with right ventricular ejection fraction. Mean preoperative proBNP levels, right ventricular end-diastolic volume index, and pulmonary insufficiency significantly (p < 0.0001) diminished 6 months after pulmonary valve replacement (231 versus 114 ng/L, 184 versus 109 mL/m2, and 44% versus 2%, respectively)., Conclusions: Plasma proBNP is elevated in patients with corrected tetralogy, severe pulmonary insufficiency, and right ventricular dilatation, and it significantly diminishes 6 months after pulmonary valve replacement, mirroring magnetic resonance imaging-documented better right ventricular ejection fraction and smaller right ventricular end-diastolic volume index. Pro-brain natriuretic peptide complements magnetic resonance imaging for cardiac assessment in patients requiring pulmonary valve insertion. Future validation of cutoff levels are required to establish proBNP as a useful diagnostic and follow-up tool in patients with chronic pulmonary insufficiency and failing right ventricles.

In patients with congenital heart disease the right ventricle (RV) may support the pulmonary (subpulmonary RV) or the systemic circulation (systemic RV). During the last 50 years evidence is accumulating that RV dysfunction develops in many of these patients and leads to considerable morbidity and mortality. Therefore RV function in certain groups of congenital heart disease patients needs close surveillance and timely and appropriate intervention to optimise outcomes. Despite major progress being made, assessing the RV either in the subpulmonary or the systemic circulation remains challenging, often requiring a multi-imaging approach and expertise (echocardiography, magnetic resonance imaging, nuclear and occasionally invasive assessment with angiography). This review discusses the implications of volume and pressure loading of the RV in the context of congenital heart disease and describes the most relevant imaging modalities for monitoring RV function.

Patients with right ventricular outflow tract reconstruction often require redo operations with time. Unique surgical problems exist in this group of patients. We report an innovative method of implantation of a pulmonary valve without the use of cardiopulmonary bypass.

Background: Right ventricular outflow tract (RVOT) reconstruction with valved conduits in infancy and childhood leads to reintervention for pulmonary regurgitation and stenosis in later life., Methods and Results: Patients with pulmonary regurgitation with or without stenosis after repair of congenital heart disease had percutaneous pulmonary valve implantation (PPVI). Mortality, hemodynamic improvement, freedom from explantation, and subjective and objective changes in exercise tolerance were end points. PPVI was performed successfully in 58 patients, 32 male, with a median age of 16 years and median weight of 56 kg. The majority had a variant of tetralogy of Fallot (n=36), or transposition of the great arteries, ventricular septal defect with pulmonary stenosis (n=8). The right ventricular (RV) pressure (64.4+/-17.2 to 50.4+/-14 mm Hg, P<0.001), RVOT gradient (33+/-24.6 to 19.5+/-15.3, P<0.001), and pulmonary regurgitation (PR) (grade 2 of greater before, none greater than grade 2 after, P<0.001) decreased significantly after PPVI. MRI showed significant reduction in PR fraction (21+/-13% versus 3+/-4%, P<0.001) and in RV end-diastolic volume (EDV) (94+/-28 versus 82+/-24 mL.beat(-1).m(-2), P<0.001) and a significant increase in left ventricular EDV (64+/-12 versus 71+/-13 mL.beat(-1).m(-2), P=0.005) and effective RV stroke volume (37+/-7 versus 42+/-9 mL.beat(-1).m(-2), P=0.006) in 28 patients (age 19+/-8 years). A further 16 subjects, on metabolic exercise testing, showed significant improvement in VO2max (26+/-7 versus 29+/-6 mL.kg(-1).min(-1), P<0.001). There was no mortality., Conclusions: PPVI is feasible at low risk, with quantifiable improvement in MRI-defined ventricular parameters and pulmonary regurgitation, and results in subjective and objective improvement in exercise capacity.

Aims: Late after total correction, Fallot patients with a long QRS duration are prone to serious arrhythmias and sudden cardiac death. Pulmonary regurgitation is a common cause of right ventricular (RV) failure and QRS lengthening. We studied the effects of pulmonary valve replacement (PVR) on QRS duration and RV volume., Methods and Results: Twenty-six consecutive Fallot patients were evaluated both pre-operatively and 6-12 months post-operatively by cardiac magnetic resonance (CMR). In this study, we present the computer-assisted analysis of the standard 12-lead electrocardiograms closest in time to the CMR studies. For the whole group, QRS duration shortened by 6+/-8 ms, from 151+/-30 to 144+/-29 ms (P=0.002). QRS duration decreased in 18 of 26 patients by 10+/-6 ms, from 152+/-32 to 142+/-31 ms. QRS duration remained constant or increased slightly in eight of 26 patients by 3+/-3 ms, from 148+/-27 to 151+/-25 ms. CMR showed a decrease in RV end-diastolic volume from 305+/-87 to 210+/-62 mL (P=0.000004). QRS duration changes correlated with RV end-diastolic volume changes (r=0.54, P=0.01)., Conclusion: Our study shows that PVR reduces QRS duration. The amount of QRS reduction is related to the success of the operation, as expressed by the reduction in RV end-diastolic volume.