Biomechanical Modeling to Inform Pulmonary Valve Replacement in Tetralogy of Fallot Patients After Complete Repair.

BACKGROUND: A biomechanical model of the heart can be used to incorporate multiple data sources (electrocardiography, imaging, invasive hemodynamics). The purpose of this study was to use this approach in a cohort of patients with tetralogy of Fallot after complete repair (rTOF) to assess comparative influences of residual right ventricular outflow tract obstruction (RVOTO) and pulmonary regurgitation on ventricular health. METHODS: Twenty patients with rTOF who underwent percutaneous pulmonary valve replacement (PVR) and cardiovascular magnetic resonance imaging were included in this retrospective study. Biomechanical models specific to individual patient and physiology (before and after PVR) were created and used to estimate the RV myocardial contractility. The ability of models to capture post-PVR changes of right ventricular (RV) end-diastolic volume (EDV) and effective flow in the pulmonary artery (Qeff) was also compared with expected values. RESULTS: RV contractility before PVR (mean 66 ± 16 kPa, mean ± standard deviation) was increased in patients with rTOF compared with normal RV (38-48 kPa) (P < 0.05). The contractility decreased significantly in all patients after PVR (P < 0.05). Patients with predominantly RVOTO demonstrated greater reduction in contractility (median decrease 35%) after PVR than those with predominant pulmonary regurgitation (median decrease 11%). The model simulated post-PVR decreased EDV for the majority and suggested an increase of Qeff-both in line with published data. CONCLUSIONS: This study used a biomechanical model to synthesize multiple clinical inputs and give an insight into RV health. Individualized modeling allows us to predict the RV response to PVR. Initial data suggest that residual RVOTO imposes greater ventricular work than isolated pulmonary regurgitation.

Percutaneous pulmonary valve implant: Two Colombian case reports.

Los pacientes con cardiopatías congénitas que afectan la continuidad del ventrículo derecho con la arteria pulmonar deben someterse con frecuencia a intervenciones debido a la limitada vida útil de los conductos quirúrgicos, lo que lleva al desarrollo de disfunción ventricular derecha por cambios en la geometría ventricular y predisposición a arritmias letales, con el consiguiente riesgo de reintervenciones. El implante valvular percutáneo pulmonar es una nueva alternativa terapéutica, menos invasiva en comparación con la quirúrgica, para pacientes seleccionados. Se realiza una revisión de las publicaciones médicas actuales disponibles y se describe la experiencia inicial del implante valvular pulmonar percutáneo en un centro colombiano de alta complejidad para el tratamiento de enfermedades cardiovasculares, en dos pacientes con disfunción del homoinjerto aórtico en posición pulmonar con doble lesión valvular, en los cuales el implante valvular pulmonar percutáneo fue una conducta exitosa. Se eligió a pacientes con cardiopatías congénitas, conductos quirúrgicos disfuncionales con estenosis o insuficiencia pulmonar significativa, y disfunción y dilatación ventricular derechas. Se empleó la técnica regular para el implante de la válvula pulmonar Melody, sin documentarse complicaciones durante el procedimiento ni al año de seguimiento. El implante percutáneo de la válvula pulmonar es un gran avance en el tratamiento de pacientes con cardiopatías congénitas, con resultados favorables a corto y mediano plazos, lo cual hace posible la restauración de la función ventricular con riesgo mínimo, frente al reemplazo quirúrgico en pacientes seleccionados.Patients with congenital heart disease that involves reconstruction of the right ventricular outflow tract must frequently undergo interventions derived from the limited useful life of the surgical canals, which leads to the development of right ventricular dysfunction due to changes in the ventricular geometry and predisposition to lethal arrhythmias, with the consequent risk of reinterventions. The percutaneous pulmonary valvular implant is a new therapeutic alternative, less invasive, compared to surgery, for selected patients. A review of the available literature is made and the initial experience of percutaneous pulmonary valve implantation in a Colombian center of high complexity for the treatment of cardiovascular diseases is described, in two patients with aortic homograft dysfunction in a pulmonary position with double valvular lesion, in which the percutaneous pulmonary valve implant was a successful strategy. Patients with congenital heart disease were chosen, with dysfunctional surgical conduits with stenosis or significant pulmonary insufficiency, with dysfunction and right ventricular dilatation. The standard technique for the implantation of the Melody pulmonary valve was used, without complications during the procedure or one year of follow-up. Percutaneous implantation of the pulmonary valve is a great advance in the management of patients with congenital heart diseases, with favorable results in the short and medium term, allowing the restoration of ventricular function with minimal risk, compared to surgical replacement in selected patients.

Implante percutáneo de válvula pulmonar: a propósito de dos casos colombianos / Percutaneous pulmonary valve implant: Two Colombian case reports

Resumen Los pacientes con cardiopatías congénitas que afectan la continuidad del ventrículo derecho con la arteria pulmonar deben someterse con frecuencia a intervenciones debido a la limitada vida útil de los conductos quirúrgicos, lo que lleva al desarrollo de disfunción ventricular derecha por cambios en la geometría ventricular y predisposición a arritmias letales, con el consiguiente riesgo de reintervenciones. El implante valvular percutáneo pulmonar es una nueva alternativa terapéutica, menos invasiva en comparación con la quirúrgica, para pacientes seleccionados. Se realiza una revisión de las publicaciones médicas actuales disponibles y se describe la experiencia inicial del implante valvular pulmonar percutáneo en un centro colombiano de alta complejidad para el tratamiento de enfermedades cardiovasculares, en dos pacientes con disfunción del homoinjerto aórtico en posición pulmonar con doble lesión valvular, en los cuales el implante valvular pulmonar percutáneo fue una conducta exitosa. Se eligió a pacientes con cardiopatías congénitas, conductos quirúrgicos disfuncionales con estenosis o insuficiencia pulmonar significativa, y disfunción y dilatación ventricular derechas. Se empleó la técnica regular para el implante de la válvula pulmonar Melody, sin documentarse complicaciones durante el procedimiento ni al año de seguimiento. El implante percutáneo de la válvula pulmonar es un gran avance en el tratamiento de pacientes con cardiopatías congénitas, con resultados favorables a corto y mediano plazos, lo cual hace posible la restauración de la función ventricular con riesgo mínimo, frente al reemplazo quirúrgico en pacientes seleccionados.

Abstract Patients with congenital heart disease that involves reconstruction of the right ventricular outflow tract must frequently undergo interventions derived from the limited useful life of the surgical canals, which leads to the development of right ventricular dysfunction due to changes in the ventricular geometry and predisposition to lethal arrhythmias, with the consequent risk of reinterventions. The percutaneous pulmonary valvular implant is a new therapeutic alternative, less invasive, compared to surgery, for selected patients. A review of the available literature is made and the initial experience of percutaneous pulmonary valve implantation in a Colombian center of high complexity for the treatment of cardiovascular diseases is described, in two patients with aortic homograft dysfunction in a pulmonary position with double valvular lesion, in which the percutaneous pulmonary valve implant was a successful strategy. Patients with congenital heart disease were chosen, with dysfunctional surgical conduits with stenosis or significant pulmonary insufficiency, with dysfunction and right ventricular dilatation. The standard technique for the implantation of the Melody pulmonary valve was used, without complications during the procedure or one year of follow-up. Percutaneous implantation of the pulmonary valve is a great advance in the management of patients with congenital heart diseases, with favorable results in the short and medium term, allowing the restoration of ventricular function with minimal risk, compared to surgical replacement in selected patients.

Multimodality imaging of quadricuspid pulmonary valve associated with pulmonary artery aneurysm.

Quadricuspid pulmonary valve is a rare entity that can be associated with pulmonary artery aneurysm. It is usually asymptomatic and diagnosed incidentally. Association with other congenital or acquired heart diseases has been reported. Echocardiography and gated CT angiography can provide useful functional and anatomic information that can help in the diagnosis and management.

Endurance Training on Congenital Valvular Regurgitation: An Athlete Case Series.

BACKGROUND: Both intense endurance training and valvular regurgitation place a volume load on the right and left ventricles, potentially leading to dilation, but their effects in combination are not well-known. PURPOSE: The purpose of this case series is to describe the combined volume load of intense endurance athletic training and regurgitant valvular disease as well as the challenging assessment of each component's cardiovascular effect. METHODS: In this article, the clinical course of three elite endurance athletes with congenital valvular disease were reviewed. RESULTS: A swimmer with aortic regurgitation, a cyclist with aortic regurgitation, and a cyclist with pulmonary regurgitation were found to have severe dilation of the associated ventricles despite continuing to train at an elite level without symptoms. CONCLUSIONS: Because of the cumulative effects of endurance training and valvular regurgitation, each athlete manifested ventricular dilation out of proportion to their valvular disease and symptoms. Although the effects of congenital valvular disease and athletic remodeling on ventricular dilation have been thoroughly studied individually, their cumulative effect is not well understood. This complicates the assessment of athletes with valvular regurgitation and underscores the need for athlete-specific recommendations for valve replacement.

[Percutaneous catheter-based implantation of artificial pulmonary valves in patients with congenital heart defects]. / Perkutan kateterbasert innsetting av kunstig pulmonalklaff ved medfødt hjertefeil.

BACKGROUND: Percutaneous catheter-based implantation of artificial heart valves is a new technique that may supplement surgery and which may be used more in the future. We here report our first experience with implantation of artificial pulmonary valves in children with congenital heart defects. MATERIAL AND METHODS: Eligible patients were those with symptoms of heart failure combined with stenosis and/or insufficiency in an established artificial right ventricular outflow tract. The valve was inserted through a catheter from a vein in the groin or neck. Symptoms, echocardiography, invasive measurements and angiography were assessed for evaluation of treatment effect. Our treatment results are reported for the period April 2007-September 2009. RESULTS: Ten patients (seven men and three women, median age 17 years) were assessed. The procedure reduced pressure in the right ventricle (p = 0.008) and resolved the pulmonary insufficiency in all patients. The median time in hospital was two days. No patients had complications that were directly associated with the implantation procedure. One patient developed a pseudoaneurysm in the femoral artery, another had a short-lasting fever two days after the procedure and one patient experienced a stent fracture that required surgery 9 months after the implantation. After 6 months all patients had a reduced pressure gradient in the right ventricular outflow tract (p = 0.008), the pulmonary insufficiency had improved (p = 0.006) and they all reported improval of symptoms. These results persisted for at least 24 months for the four patients who were monitored until then. INTERPRETATION: Percutaneous catheter-based implantation of artificial pulmonary valves improves hemodynamics in the right ventricle of selected patients with congenital heart defects. A randomized controlled study should be undertaken to provide a stronger evidence-base for usefulness of this procedure.

The pulmonary valve.

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.

First-in-man implantation of a novel percutaneous valve: a new approach to medical device development.

AIMS: To present our experience of 'first-in-man' implantation of a new percutaneous pulmonary valve into a dilated pulmonary trunk, using patient specific data to influence the design of the device and ensure patient safety. METHODS AND RESULTS: A 42-year-old with severe pulmonary insufficiency underwent computed tomography assessment of his pulmonary trunk. This information was utilised to create computer and rapid prototyping models that were used to customise and test the device, which was subsequently implanted into the patient. Following the procedure, the clinical, haemodynamic and morphological success of this approach was determined. The new device was safely and successfully implanted as predicted by the pre-procedural modelling. There was excellent device stability, no stent fractures, no pulmonary incompetence and only trivial para-device leak at six months follow-up. The patient described marked symptomatic improvement. CONCLUSIONS: Safe, effective percutaneous pulmonary valve implantation is possible in a patient with a dilated, native pulmonary trunk. Our methodologies, which have evolved as a direct result of recent advances in four-dimensional imaging techniques, challenge the conventional stepwise pathway of bench and animal testing prior to human application, and may be safer and more relevant, potentially reducing the number of animal experiments necessary for testing new medical devices.

Quadricuspid pulmonary valve identified by transthoracic echocardiography.

The quadricuspid pulmonary valve is a rare congenital anomaly. It tends to be clinically quiescent. Its diagnosis by two-dimensional echocardiography could be very difficult because of the anatomical features. We report on the echocardiographic findings of a 66-year-old female patient with mitral and aortic regurgitation of rheumatic origin and severe pulmonary hypertension. There was an aneurismatic dilation of the pulmonary artery trunk allowing visualization of the short-axis view of the pulmonary valve. It showed four cusps of similar size and an important deficit of central coaptation. Very few cases of the quadricuspid pulmonary valve are documented in live patients.

Perventricular pulmonary valvuloplasty under echocardiographic guidance.

We report the case of a small neonate with a complex congenital heart disease who successfully underwent a perventricular pulmonary valvuloplasty during the early postoperative period, using echocardiographic guidance alone without fluoroscopy. We describe the technique and the advantages of this novel procedure.

Tetralogy of Fallot with absent pulmonary valve syndrome.

Tetralogy of Fallot with absent pulmonary valve syndrome is a rare variant of tetralogy of Fallot marked by severe pulmonary insufficiency in utero and significant, sometimes massive, dilation of the pulmonary arteries. This syndrome can be associated with airway abnormalities that can cause respiratory compromise. Patients who present with respiratory symptoms early in life continue to present a major clinical challenge associated with relatively high mortality rates, typically in the 20% to 30% range. A variety of surgical techniques have been developed to address absent pulmonary valve syndrome that may improve long-term outcomes.

Right atrial isomerism in four siblings.

Heterotaxy syndromes, right or left atrial isomerism, result from disruption of left-right axis determination and their manifestations include complicated heart defects. Recent studies in model organisms have revealed complex genetic pathways and several genes involved in this process. In affected humans, however, molecular studies have identified mutations in a small number of individuals, while in most the cause remains unknown. Furthermore, although family data suggest, autosomal recessive inheritance, such genes have not yet been identified. We have studied six members of a family, four children affected with right atrial isomerism (RAI) and their healthy parents, for disturbances of left-right axis development. The children, one female and three males who all had complicated heart defects, succumbed and had an autopsy. Their nonconsanguineous parents were examined by cardiac and abdominal ultrasound or MRI. In all four children the heart defects included single ventricle with dysplastic atrioventricular (AV) valve, total anomalous pulmonary venous drainage (TAPVD), and malposition of great arteries (MGA) with pulmonary stenosis (PS). All had asplenia; two also had dextrocardia and abdominal situs inversus. The diagnosis of RAI was made postnatally in the first child and prenatally in others. Two siblings had no surgery and died as a newborn, one with obstructed supracardiac TAPVD and the other with regurgitating AV valve. Two children underwent heart surgery. One had repair of obstructive infracardiac TAPVD but died in infancy. The other underwent both hemi-Fontan operation and heart transplantation but died at the age of 2 years. This is the first report describing four children with RAI in the same family. The occurrence of RAI in male and female siblings without any indication of left-right axis abnormalities in their parents suggests autosomal recessive inheritance of human isomerism.

Correction of absent pulmonary valve syndrome using a pericardial valved conduit.

Absent pulmonary valve syndrome in a 4-month-old infant was successfully corrected using a fresh autologous pericardial trileaflet valved conduit. He recovered from operation with only mild pulmonary regurgitation at 4 months postoperatively. This technique is an effective alternative for infants with congenital heart disease who need tissue valved conduits. It may be more suitable than the aortic homograft by reason of the shortage of small homografts and its lower costs.

Isolated congenital absence of a single pulmonary valve cusp.

Isolated absence of a single pulmonary valve is extremely unusual. We present a 16-year-old male with the absence of one cusp resulting in significant pulmonary regurgitation, right ventricular enlargement, and dilatation of the main pulmonary artery and its branches. Surgery consisted of creating a valve cusp from the posterior wall of the pulmonary artery at the base of the pulmonary trunk. Follow-up at 3.5 years revealed good results with only mild pulmonary stenosis and regurgitation.

Diagnosis and natural history of isolated congenital pulmonary regurgitation in fetal life.

We describe a rare instance of isolated pulmonary regurgitation caused by a dysplastic pulmonary valve which was detected prenatally. Fetal echocardiography demonstrated severe pulmonary regurgitation, and progressive cardiomegaly because of right ventricular volume overload. After birth, conservative therapy was successful in alleviating the pulmonary vascular resistance, and the pulmonary regurgitation gradually decreased.

Echocardiographic evaluation of isolated pulmonary valve disease in adolescents and adults.

Congenital pulmonary valve disease is often not discovered until adolescence or adulthood. Transthoracic two-dimensional echocardiography can provide detailed information regarding right ventricular outflow anatomy, although images are often less satisfactory than those obtained in infants and children. The more recent addition of biplanar transesophageal echocardiography has enhanced our ability to image the right ventricular outflow tract, pulmonary valve, and pulmonary artery noninvasively. Pulsed and continuous-wave Doppler estimates of subvalvular and transvalvular gradients have proved to be accurate. Doppler color flow mapping has proved useful in determining the location and direction of stenotic and regurgitant flow. With no accepted standard for comparison, quantification of regurgitation remains problematic. In many cases, echocardiography has replaced catheterization and angiography in the evaluation and long-term follow-up of congenital pulmonary valve disease before and after intervention.