Pulmonary valve stenosis in the adult patient: pathophysiology, diagnosis and management

Pulmonary Valve Stenosis: From Diagnosis to Current Management Techniques and Future Prospects

Pulmonary stenosis (PS) is mainly a congenital defect that accounts for 7-12% of congenital heart diseases (CHD). It can be isolated or, more frequently, associated with other congenital defects (25-30%) involving anomalies of the pulmonary vascular tree. For the diagnosis of PS an integrated approach with echocardiography, cardiac computed tomography and cardiac magnetic resonance (CMR) is of paramount importance for the planning of the interventional treatment. In recent years, transcatheter approaches for the treatment of PS have increased however, meaning surgery is a possible option for complicated cases with anatomy not suitable for percutaneous treatment. The present review aims to summarize current knowledge regarding diagnosis and treatment of PS.

Multimodality Imaging of the Neglected Valve: Role of Echocardiography, Cardiac Magnetic Resonance and Cardiac Computed Tomography in Pulmonary Stenosis and Regurgitation

The pulmonary valve (PV) is the least imaged among the heart valves. However, pulmonary regurgitation (PR) and pulmonary stenosis (PS) can occur in a variety of patients ranging from fetuses, newborns (e.g., tetralogy of Fallot) to adults (e.g., endocarditis, carcinoid syndrome, complications of operated tetralogy of Fallot). Due to their complexity, PR and PS are studied using multimodality imaging to assess their mechanism, severity, and hemodynamic consequences. Multimodality imaging is crucial to plan the correct management and to follow up patients with pulmonary valvulopathy. Echocardiography remains the first line methodology to assess patients with PR and PS, but the information obtained with this technique are often integrated with cardiac magnetic resonance (CMR) and computed tomography (CT). This state-of-the-art review aims to provide an updated overview of the usefulness, strengths, and limits of multimodality imaging in patients with PR and PS.

Exercise cardiac magnetic resonance imaging to assess dynamic right ventricular outflow tract obstruction in congenital heart disease: a case report

Background

Right ventricular outflow tract obstruction in patients with congenital heart disease is usually assessed using echocardiographic peak instantaneous gradient at rest. Since right ventricular outflow tract obstruction may change during exercise (dynamic right ventricular outflow tract obstruction), we present a case emphasizing the potential use of exercise cardiac magnetic resonance imaging (CMR).

Case summary

We discuss a 15-year-old patient with repaired mid-ventricular sub-pulmonary stenosis type double-chambered right ventricle causing right ventricular outflow tract obstruction and symptoms on exertion. In this case, exercise CMR imaging provided additional information, allowing adequate surgical planning.

Discussion

The additional value of exercise CMR imaging in a case of right ventricular outflow tract obstruction was described. Although exercise cardiac magnetic resonance imaging did not show a significant increase in peak gradient across the right ventricular outflow tract obstruction, shifting and D-shaping of the interventricular septum with subsequent insufficient left ventricular filling (preload) was observed in the patient with recurrent double-chambered right ventricle. This case demonstrates how exercise CMR imaging can be helpful in the clinical decision beyond standard echocardiographic evaluation by providing additional evidence of adverse haemodynamics during exercise.

Echocardiographic assessment of the tricuspid and pulmonary valves: a practical guideline from the British Society of Echocardiography

Transthoracic echocardiography is the first-line imaging modality in the assessment of right-sided valve disease. The principle objectives of the echocardiographic study are to determine the aetiology, mechanism and severity of valvular dysfunction, as well as consequences on right heart remodelling and estimations of pulmonary artery pressure. Echocardiographic data must be integrated with symptoms, to inform optimal timing and technique of interventions. The most common tricuspid valve abnormality is regurgitation secondary to annular dilatation in the context of atrial fibrillation or left-sided heart disease. Significant pulmonary valve disease is most commonly seen in congenital heart abnormalities. The aetiology and mechanism of tricuspid and pulmonary valve disease can usually be identified by 2D assessment of leaflet morphology and motion. Colour flow and spectral Doppler are required for assessment of severity, which must integrate data from multiple imaging planes and modalities. Transoesophageal echo is used when transthoracic data is incomplete, although the anterior position of the right heart means that transthoracic imaging is often superior. Three-dimensional echocardiography is a pivotal tool for accurate quantification of right ventricular volumes and regurgitant lesion severity, anatomical characterisation of valve morphology and remodelling pattern, and procedural guidance for catheter-based interventions. Exercise echocardiography may be used to elucidate symptom status and demonstrate functional reserve. Cardiac magnetic resonance and CT should be considered for complimentary data including right ventricular volume quantification, and precise cardiac and extracardiac anatomy. This British Society of Echocardiography guideline aims to give practical advice on the standardised acquisition and interpretation of echocardiographic data relating to the pulmonary and tricuspid valves.