Background
Tetralogy of Fallot is a rare congenital cardiac diseases occurring in one of every 35,0000-30,000 live births. This malformation consists of ventricular septal defect, obstruction of the right ventricular outflow tract, override of the ventricular septum by the aortic root, and in consequence right ventricular hypertrophy. It is the most common cyanotic heart defect. Abnormalities of the pulmonary arteries following palliative or corrective surgery for tetralogy of Fallot (TOF) are common. There are only a few written cases of Tetralogy of Fallot with absence of pulmonary branch. Approximately 15% of patients with ToF have
a deletion of chromosome 22q11.
Case description
A 21-year-old woman with Tetralogy of Fallot, pulmonary valve stenosis and absence of the right pulmonary artery was admitted to hospital. Surgical correction was performed at the age of 8 years. She has reported reduced exercise tolerance and frequent upper respiratory tract infections since operation. The patient was in NYHA class II on admission. Over the base of the heart systolic murmur was heard. Chest x-ray revealed high position of the right diaphragm, reduced pulmonary vascularity and moderately enlarged cardiac silhouette.
The ECG at rest showed sinus rhythm with a heart rate of 60 beats/minute, right axis deviation, right bundle branch block and right ventricular hypertrophy. Holter monitoring did not reveal significant cardiac arrhythmias or conduction disturbances. The cardiopulmonary exercise test showed reduced exercise tolerance and maximal oxygen consumption (VO2 max 17, 7 ml/kg/min, 54% expected value). The oxygen saturation of arterial blood during exercise decreased from 94% at rest to 86% at peak exercise. The echocardiography found normal left ventricular size and function, enlarged right ventricle and right atrium, muscular ridge causing obstruction of the right ventricular outflow tract, thickened pulmonary valve leaflets, moderate tricuspid and pulmonary regurgitation. The measured pressure gradient in the right ventricular outflow tract was 62/37 mmHg. No ventricular shunting was observed. CT scanning confirmed the absence of the right pulmonary artery. MR imaging confirmed subvalvular pulmonary stenosis with peak pressure gradient 33 mmHg in the right ventricular outflow tract. The measured pressure gradient across the pulmonary valve was 19 mmHg. The end diastolic right ventricular volume was 135 ml.
Guidelines
2010 ESC Guidelines for the management of grown-up congenital heart disease:
After correction of tetralogy of Fallot the residual right ventricular outflow tract obstruction is a common late complication. This can occur at the infundibulum, at the level of the pulmonary valve and main pulmonary trunk, distally, beyond the bifurcation, and occasionally in the branches of the left and right pulmonary artery. Reoperations should be performed in symptomatic patients with severe pulmonary regurgitation and/or stenosis (RV systolic pressure >60 mmHg, TR velocity >3.5m/s) – class I C.
Reoperations should be considered in asymptomatic patients with severe pulmonary regurgitation and/or pulmonary stenosis when at least one of the following criteria is present:
• Decrease in objective exercise capacity
• Progressive right ventricular dilation
• Progressive right ventricular systolic dysfunction
• Progressive tricuspid regurgitation (at least moderate)
• RVOTO with RV systolic pressure >80 mmHg (TR velocity >4.3 m/s)
• Sustained atrial/ventricular arrhythmias – class IIa C.
References
1. Greenberg SB, Crisci KL, Koenig P, Robinson B, Anisman P, Russo P. Magnetic resonance imaging compared with echocardiography in the evaluation of pulmonary artery abnormalities in children with tetralogy of Fallot following palliative and corrective surgery. Pediatr Radiol. 1997 Dec;27(12):932-5.
2. ESC Guidelines for the management of grown-up congenital heart disease. European Heart Journal (2010) 31, 2915–2957
Experts’ comments:
1. Janusz Skalski, MD, PhD: Because of elevated pressure gradient in the right ventricular outflow tract repair of outflow tract obstruction should be performed.
2. Jacek Pająk, MD, PhD: The patient is clinically stable and conservative treatment is proposed. Surgical intervention should be considered in case of clinical symptoms, increased RVOT gradient, significant tricuspid regurgitation or cardiac arrhythmias.
3. Olga Trojnarska MD, PhD: Pulmonary stenosis in this patient is moderate, therefore it does not require surgical repair. Taking into consideration normal function of the left ventricle and slightly decreased blood oxygen saturation I do have doubts concerning cardiopulmonary test result (RQ>1). If the patient stays under supervision of anexperienced medical center, planned pregnancy is of moderate risk.
4. Zbigniew Gąsior, MD, PhD: Stress echocardiography should be performed before planning pregnancy to determine how the pressure gradient in the right ventricular outflow tract responds to stress.
5. Tomasz Miszalski-Jamka MD, PhD: MR imaging confirms subvalvular pulmonary stenosis – peak pressure gradient of 33 mmHg in the right ventricular outflow tract and pressure gradient across the pulmonary valve is 19 mmHg.
6. Grzegorz Kopeć MD, PhD: Serial echocardiographic studies should be considered to evaluate the progression of pulmonary stenosis. Stress echo may help stratify the risk associated with planned pregnancy.
Conclusions:
The patient qualifies for observation. Successful pregnancy in this patient is possible but not recommended due to high risk. Stress echocardiography before planning pregnancy is recommended to determine the pressure gradient in the right ventricular outflow tract.
Authors:
Lidia Tomkiewicz-Pająk1, Leszek Drabik1, Maciej Krupiński2, Jakub Podolec3, Paweł Banyś2, Paweł Rubiś1, Piotr Podolec1
Experts:
Janusz Skalski4, Jacek Pająk5, Olga Trojnarska6, Zbigniew Gąsior7, Tomasz Miszalski – Jamka 2
1 Department of Cardiac and Vascular Diseases, John Paul II Hospital, Krakow, Poland
2 Center for Diagnosis, Prevention and Telemedicine, John Paul II Hospital, Krakow, Poland
3 Department of Hemodynamics and Angiocardiography, John Paul II Hospital, Krakow, Poland
4 Department of Pediatric Cardiac Surgery, Polish-American Children’s Hospital, Jagiellonian University, Krakow, Poland
5 Independent Public Clinical Hospital No.6, Medical University of Silesia in Katowice, Upper Silesia Center of the children’s Health. John Paul II, Pediatric Heart Surgery Department, Poland
6 1st Department of Cardiology, Poznan University of Medical Sciences, Poznan, Poland
7 2nd Department of Cardiology, Medical University of Silesia, Katowice, Poland
