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Pulmonary regurgitation after repair of tetralogy of Fallot (ToF) is almost inevitable and in the past has required repeat surgery for replacing the regurgitant pulmonary valve. After 2000, percutaneous pulmonary valve implantation (PPVI) with balloon-expandable valves has replaced the surgical approach in a select group of patients. However, PPVI with the commercially available balloon-expandable valves have limitations because of their size, being applicable to right ventricle–pulmonary artery conduits or bioprosthetic valves. They have not been considered suitable for native dilated right ventricular outflow tracts (RVOT) after a transannular patch repair technique, which form about 70–75% of the patients. Novel self-expanding pulmonary valves have been developed for use in such dilated native outflow tracts. Early experience with these valves, although limited, has been encouraging, suggesting that self-expandable pulmonary valves can be implanted safely, with good short- and mid-term results in patients with native RVOT. This chapter summarises the new transcatheter self-expanding valves available for the management of pulmonary regurgitation after surgical repair of ToF, in patients in whom the shape and size of the RVOT, have previously been considered unsuitable for transcatheter valve implantation.

Pulmonary stenosis is a common cardiac defect. It is present either in isolation or associated with other congenital heart defects. Obstruction may occur at various levels. The presentation and clinical manifestations depend on the age, severity of the obstruction and associated cardiac defects. The goal of treatment is to relieve obstruction without significant pulmonary regurgitation or residual gradient. Currently catheter-based interventions remain the standard treatment for acute symptoms and to prevent progressive right ventricular failure related to pulmonary stenosis. Surgery is reserved for failed catheter interventions, multi-level obstructions, complex cases or need for additional source of pulmonary blood flow.

Echocardiography remains the gold standard and first level choice for the study of heart valve diseases because of its availability, high temporal resolution for the study of valvular flows, limited costs and possibility to perform the examination in any condition. Nevertheless CMR has specific advantages to be considered in specific settings. CMR offers specific advantages: better accuracy in the evaluation of biventricular volumes and function, possibility of tissue characterization (scar assessment) and more accurate quantification of aortic and pulmonary regurgitation than echocardiography.

While a substantial minority of patients with repaired tetralogy of Fallot (rTOF) have normal exercise performance, as a group their performance is mild-moderately decreased, and there is a cohort with markedly decreased exercise capacity. The factors responsible for the rTOF patient’s exercise intolerance are probably diverse and may vary from patient to patient. In most cases, residual cardiovascular lesions (pulmonary stenosis, pulmonary regurgitation, and especially right ventricular dysfunction) are the most important issues. The dynamic interplay between these variables and their effect on exercise function is complex, however, and can vary over time. The combination of an incompetent pulmonary valve and residual pulmonary artery stenoses is particularly deleterious and results in interesting physiology that is uniquely appreciated in the exercise physiology laboratory. Exercise testing can be safely performed in a wide range of TOF patients. Data from exercise testing in rTOF patients has important prognostic and clinical implications.

In this chapter, we will present an overview of diseases that affect the tricuspid and pulmonary valves, discuss 2D and 3D echocardiographic methods that allow their precise description, and highlight how to assess the severity of valvular regurgitation and stenosis.

The characteristic features of tetralogy of Fallot including the large perimembranous malalignment VSD, overriding of the aorta and obstruction of the right ventricular outflow tract can be well displayed by 2D echocardiography. Colour Doppler provides important information regarding shunting across the VSD, allows detection of additional muscular VSDs and helps to clarify the sites of obstruction of the right ventricular outflow tract. Colour Doppler is also required for clarification of collateral lung perfusion and laterality of the aortic arch as well as for detection of subclavian artery anomalies. PW and CW Doppler provide the possibility to quantify the gradient across the right ventricular outflow tract. Following surgical repair, PW and CW Doppler are important tools for quantification of systolic right ventricular pressure, residual gradient across the right ventricular outflow tract and pulmonary regurgitation.

Approximately 22 % of all congenital heart disease patients have an abnormality of the right ventricular outflow tract. During the course of surgery for this condition, approximately 23 % of the patients will receive some form of a valved RV to PA conduit. These patients are candidates for the Medtronic Melody transcatheter pulmonary valve (TPV) (Medtronic, Minneapolis, MN) or, in some parts of the world, the Edwards SAPIEN pulmonic valve (Edwards Lifesciences Corp., Irvine, CA). However, approximately 77 % of patients will have surgical correction of the RV outflow tract with patch enlargement, with or without pulmonary valvectomy, and many will have a transannular patch placed. Most of these patients will be left with significant pulmonary regurgitation (PR) resulting in RV volume overload and potential RV dysfunction later in life. Developing a transcatheter pulmonary valve to fit this complex anatomy was much more challenging than the design of the Melody TPV for RV-PA conduit dysfunction.

A 20-year-old woman with a history of atypical chest pain was referred to our echocardiography laboratory for more precise evaluation. Physical examination showed a systolic ejection murmur (grade III/VI) and a diastolic murmur (grade II/VI) in the second left intercostal space. Echocardiography revealed normal left and right ventricular sizes and functions, together with mild right ventricular hypertrophy.