Background
Bicuspid aortic valve (BAV) is the most common heart defect that occurs in 1-2% live births. BAV is associated with abnormalities of elastic fibres in aortic media that often leads to aortic dilatation. Moreover, aortic stenosis (AS) may develop, even at a young age. Patients with AS can remain asymptomatic for many years. Among the asymptomatic patients with preserved LV systolic function the risk of death is about 1%, but increases significantly when symptoms occur. Deterioration of the left ventricle (LV) systolic function is associated with the worse outcome after surgical treatment. Standard treatment of AS is aortic valve replacement (AVR) which is associated with operative mortality of 1.2% in patients under the age of 56 and increases with more advanced age. Aortic valve repair is possible only when the valve morphology is suitable and usually can be performed only in children without previous interventions on the valve. Transcatheter aortic valve implantation (TAVI) seem to be very promising but nowadays is reserved for patients disqualified from AVR due to high operative risk. Moreover, TAVI is currently contraindicated in bicuspid aortic valve.
Case presentation
We present a case of a 17-year-old man with congenital aortic stenosis. The patient was admitted to our center in October 2012 for further evaluation. He denied symptoms (chest pain, dyspnea, syncope) or decreased exercise capacity. In 2003 baloon valvuloplasty had been carried out. The transtoracic echocardiography and clinical examination was performed every year in pediatric cardiology and progression of the transvalvular gradient as well as left ventricle (LV) hypertrophy development was observed (table 1).
The patient was admitted to our hospital for further evaluation and qualification to aortic valve replacement. Physical examination revealed systolic murmur best heard on upper right sternal border, heart rate was regular 60 bpm, blood pressure 100/70 mmHg, vesicular breath sounds. The liver edge was not palpable. The patient didn’t have peripheral edema. The laboratory tests were unremarkable (table 2). The ECG showed sinus rhythm 60 bpm, left ventricle hypertrophy. In the 24-hours ECG monitoring minimal heart rate was 44 bpm at 10.17 PM, maximal heart rate 109 bpm and mean hart rate 60 bpm. The echocardiographic examination showed concentric left ventricle (LV) hypertrophy (interventricular septum thickness of 14.3 mm and posterior wall of 12.9 mm), bicuspid AV (fusion of the left- and right coronary leaflets) with the gradient of 74/42 mmHg, aortic valve area (AVA) of 1.44 cm² and AVA indexed to body surface area of 0.75 cm²/m². Left ventricle (LV) systolic function was normal with ejection fraction (EF) of 74% , also LV diastolic function was normal (E/A =1.86, E’lateral= 0.11 m/s, E/E’lateral= 0.78). The exercise test was performed and despite lack of symptoms showed ST segment depression in II, III, aVF, V5-V6 up to 2.2 mm. Maximal oxygen consumption was 26.5 ml/kg/min that is 60% of predicted values.
The patient was initially treated by metoprolol succinate 50 mg in the morning then by metoprolol tartrate 25 mg twice a day. The patient’s medical history was presented on the Meeting of the Center for Rare Cardiovascular Diseases where he was qualified to the surgical treatment.
| 05.2010 | 05.2011 |
| LV hypertrophy, MVR I°, AVA 3.3 cm²,AVAI 1.8 cm² /m² , AVG 56/29 mmHg, Ao root 37.8 mm, LVPW 10mm, IVS 9/13 mm, LVmass 121g/m² | LV hypertrophy, AVA 2.6 cm², AVG 59-61 mmHg, mild AVR, mild MVR, Ao root 33 mm, LVEF 79.4% |
Table 1. LV-left ventricle, EF-ejection fraction, AVA-aortic valve area, MVR- mitral valve reguritance, Ao- aorta, LVPW- LV posterior wall, IVS- intrerventricular septum
| •WBC 4.98 x10³/µl |
| •RBC 4.98 x10³/µl |
| •Hemoglobin 14.7 g/dl |
| •HCT 43.0 % |
| •PLT 107 x10³/µl |
| •INR 1.00 |
| •Creatynine 79 µmol/l |
| •Total cholesterol 3.49 mmol/l |
| •HsCRP 1.41 mg/L |
| •ALT 14 U/l |
| •AST 16 U/l |
| •Glucose 5.3 mmol/l |
Table 2.
Current guidelines
According to the current guidelines patients with symptomatic severe AS, patients with severe AS and impaired LV systolic function (LV ejection fraction<50%), patients with symptomps occurring during exercise test and patients with severe AS undergoing CABG, surgery on ascending aorta or other valve should be scheduled for the AVR. The surgical treatment should be considered in patients with severe AS and high risk when they are suitable for TAVI, in asymptomatic patients when drop of the blood pressure during exercise is observed, with moderate AS when CABG, surgery on ascending aorta or other valve is planned, with low-flow low-gradient AS with preserved LV systolic function- after careful examination, with low-flow low-gradient AS with compromised LV systolic function- after confirmation of flow reserve, finally, in asymptomatic severe AS if surgical risk is low and peak transvalvular velocity is over 5.5 m/s and/or when valve is severly calcified and yearly progression of the velocity ≥ 0.3. AVR may be considered in symptomatic patients with low-flow, low-gradient severe AS and no flow reserve as well as in patients with asymptomatic severe AS with normal systolic LV function when al least one of factors are present: markedly elevated level of the natiuretic peptide, increase of mean pressure gradient more than 20 mmHg during exercise or large LV hypertrophy in patient without hypertension.
References
1. Vahanian A, Alfieri O, Andreotti F et al. Guidelines on the management of valvular heart disease (version 2012): the Joint Task Force on the Management of Valvular Heart Disease of the European Society of Cardiology (ESC) and the European Association for Cardio-Thoracic Surgery (EACTS). Eur J Cardiothorac Surg. 2012;42:S1-44.
2. The European Association for Cardio-Thoracic Surgery. Fourth EACTS adult cardiac surgical
database report 2010. Henley-on-Thames, UK Dendrite Clinical Systems Ltd; ISBN 9781-9039-682-60.
3. Baumgartner H, Bonhoeffer P, De Groot NM et al. ESC Guidelines for the management of grown-up congenital heart disease (new version2010). Eur Heart J. 2010;31:2915-57.
Expert’s comments:(Written authorization required from each expert)
1. Bogusław Kapelak, MD, PhD
In the future the patient should be qualified to the AVR. The aortic valve repair is not possible in this case because of previous balloon valvuloplasty and calyfications on the non-coronary leaflet. Currently , due to asymptomatic status, preserved LV function, good exercise capacity and young age the patient can be observed. The control echocardiography and clinical assessment is necessary after 6 months.
2. Jacek Kołcz MD, PhD
The patient should be monitored and have controlled echocardiographic examination within six months.
3. Prof. Tadeusz Przewłocki MD, PhD
The patient should be monitored and definitive treatment should be performed when the growth period will be over. AVR will be necessary.
Expert’s conclusions:
The patient did not have any symptoms, there was no blood pressure drop on exercise test, systolic as well as diastolic function of the left ventricle was normal. Because of that the definitive treatment can be delayed. Due to previous balloon valvuloplasty and calcifications on the leaflets aortic valve repair probably will not be possible. The patient should be monitored and clinical assessment with echocardiographic examination should be performed within six months period. Aortic valve replacement will be unavoidable in the future.
Authors:
Joanna Łuszczak MD1, Lidia Tomkiewicz- Pajak MD, PhD1, Maria Olszowska MD, PhD1, Prof. Piotr Podolec MD, PhD1, Paweł Rubiś MD, PhD1, Jakub Podolec MD.1
Experts:
Bogusław Kapelak MD, PhD2, Jacek Kołcz MD, PhD3, Prof. Tadeusz Przewłocki MD, PhD2
1Department of Cardiac and Vascular Disease in John Paul II Hospital, Institute of Cardiology, Faculty of Medicine, Jagiellonian University, Krakow, Poland.
2Department of Cardiac, Vessels Surgery and Transplantology, Jagiellonian University College of Medicine, John Paul II Hospital, Krakow, Poland
3Department of Pediatric Cardiac Surgery, Polish-American Children’s Hospital, Krakow, Poland