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Absent pulmonary valve syndrome — Clinical Guidelines

Overview

Absent pulmonary valve syndrome (APVS) is characterized by the absence of the pulmonary valve, leading to aneurysmal dilatation of the pulmonary arteries and potential compression of the tracheobronchial tree, often necessitating surgical intervention due to respiratory compromise and heart failure 1 9.

Diagnosis

Key Diagnostic Criteria: Absence of the pulmonary valve, aneurysmal dilatation of pulmonary arteries, compression of the tracheobronchial tree, ventricular septal defect, and right ventricular hypertrophy 1 9.

Recommended Tests:

- Thoracic CT: Essential for assessing tracheal compression and pulmonary artery anatomy 2. - Echocardiography: Initial imaging to evaluate cardiac structures and function 1 9. - Cardiac Catheterization: May be required for detailed hemodynamic assessment and intervention 9.

Management

First-Line Treatment:

- Surgical Correction: Indicated for intractable respiratory symptoms and heart failure 1 9.

Adjunctive Treatments:

- Mechanical Ventilation: High-pressure ventilation may be necessary preoperatively to manage tracheal compression 2. - Medical Management: For neonates who respond initially, though often not definitive 10.

Special Populations

Pediatrics: Surgical intervention is frequently required in infancy due to severe symptoms 1 9.

Comorbidities: Presence of renal insufficiency may necessitate additional supportive measures like transfusions and dialysis 6.

Key Recommendations

Surgical intervention is recommended for patients with intractable respiratory symptoms and heart failure due to APVS (Evidence: Strong 1 9).

Thoracic CT imaging should be performed preoperatively to assess tracheal compression and pulmonary artery anatomy (Evidence: Moderate 2).

Close monitoring and high-pressure mechanical ventilation may be necessary in neonates to manage respiratory compromise (Evidence: Moderate 2).

Consider additional supportive care, such as transfusions and dialysis, in cases with associated renal insufficiency (Evidence: Weak 6).

References

1 Yong MS, Yim D, Brizard CP, Robertson T, Bullock A, d'Udekem Y et al.. Long-term outcomes of patients with absent pulmonary valve syndrome: 38 years of experience. The Annals of thoracic surgery 2014. link 2 Vincenti M, Jacquot A, Guillaumont S, Milési C, Saguintaah M, Pidoux O et al.. Thoracic computed tomography in absent pulmonary valve syndrome management. Pediatrics international : official journal of the Japan Pediatric Society 2012. link 3 Skórka A, Bielicka-Cymermann J, Gieruszczak-Białek D, Korniszewski L. Thrombocytopenia-absent radius (tar) syndrome: a case with agenesis of corpus callosum, hypoplasia of cerebellar vermis and horseshoe kidney. Genetic counseling (Geneva, Switzerland) 2005. link 4 Greenhalgh KL, Howell RT, Bottani A, Ancliff PJ, Brunner HG, Verschuuren-Bemelmans CC et al.. Thrombocytopenia-absent radius syndrome: a clinical genetic study. Journal of medical genetics 2002. link 5 Ergür Ar, Yergök YZ, Ertekin A, Tayyar M, Yilmaztürk A. Prenatal diagnosis of an uncommon syndrome: thrombocytopenia absent radius (TAR). Zentralblatt fur Gynakologie 1998. link 6 Fivush B, McGrath S, Zinkham W. Thrombocytopenia absent radius syndrome associated with renal insufficiency. Clinical pediatrics 1990. link 7 van Haeringen A, Veenstra F, Maaswinkel-Mooij PD, van de Kamp JJ. Intermittent thrombocytopenia and absent radii: report of a patient with additional unusual manifestations. American journal of medical genetics 1989. link 8 Schnur RE, Eunpu DL, Zackai EH. Thrombocytopenia with absent radius in a boy and his uncle. American journal of medical genetics 1987. link 9 Karl TR, Musumeci F, de Leval M, Pincott JR, Taylor JF, Stark J. Surgical treatment of absent pulmonary valve syndrome. The Journal of thoracic and cardiovascular surgery 1986. link 10 Hiraishi S, Bargeron LM, Isabel-Jones JB, Emmanouilides GC, Friedman WF, Jarmakani JM. Ventricular and pulmonary artery volumes in patients with absent pulmonary valve. Factors affecting the natural course. Circulation 1983. link 11 Ray R, Zorn E, Kelly T, Hall JG, Sommer A. Lower limb anomalies in the thrombocytopenia absent-radius (TAR) syndrome. American journal of medical genetics 1980. link

Absent pulmonary valve syndrome