Pulmonary atresia with intact ventricular septum: long term follow-up after biventricular vs. univentricular correction

Biventricular surgical repair has been employed as a definitive repair in
patients with pulmonary atresia with intact ventricular septum (PA/IVS).
Theoretically, biventricular physiology is superior to classic univentricular
correction (Fontan procedure), because the right ventricle actively sustains
the pulmonary circulation. This approach may prevent right sided congestion
with tachyarrhythmias, liver function and coagulation disorders, frequently
encountered in the group with univentricular repair. However, biventricular
repair may not be a guarantee for superior performance over univentricular
repair in PA/IVS as shown by recent small studies. Impaired left and right
ventricular performance at the time of definitive repair might be responsible
for some disappointing results in the biventricular group. Structural anomalies
of the right ventricle such as hypoplasia and coronary perfusion variations may
play an important role. In addition, LV function in PA/IVS may be impaired
although this has not been adequately investigated in detail. Data on long-term
follow-up are limited in this patient group and need further investigation.

1- To investigate cardiac performance and clinical course after biventricular
vs. univentricular repair in PA/IVS. 2- To correlate pre- operative RV and LV
function with present RV and LV function. 3- To assess myocardial structural
anomalies, which could contribute to decreased post-operative cardiac
performance. 4- To assess retrospectively which patients with PA/IVS could have
benefited from biventricular repair.

Prospective patient based study
Cardiac performance is assessed using dobutamine stress MRI. Delayed contrast
hyperenhancement MRI is used for identification of myocardial fibrosis.
Clinical outcome will be evaluated by: exercise test, NYHA functional class,
and quality of life questionnaires. Serum BNP is measured as parameter for
cardiac failure. Echocardiographic studies are performed and compared with
preoperative data regarding size of the tricuspid valve and RV. The data of the
two PA/IVS groups will be compared.

The burden of participation are that the patient has to visit the MAC twice.
During the first visit the questionaries will be discussed and the exercise
will be performed. During this test the patient will be asked to exercise to
his or her maximum. During this test a (pediatric) cardiologist will be present
and the patient can resign at any moment. This examination will pose no
additional burden or risk than performance of exercise during normal life.
During the second visit, blood will be taken during the placement of an
IV-canula, neede during the MRI examination, to determine BNP. This procedure
is painful but short. During the MRI-examination the IV-canula is used to
infuse contrastagent. The patient will notice the infusion because of a cold
feeling in his or her arm. This contrastagent poses no risk in this
patientgroup and is widely used. Therse is a small risk of allergic reaction
for this contrastagent, whcih is rare.
During the exercise part of the MRI-examination, dobutamine will be used to
mimic physical exercise. During infusion of dobutamine the heart rate and
cardiac output will increase. The patient will notice increase of the
heartrate. If all precausions are made this examination will pose minimal risks
to the patient. A (pediatric)cardiologist will be present during all
examinations and during the MRI-scan the will be monitored using a camera, an
alarmbutton, a continuous ECG registration and a continous oxygen-registration

The patient will benefit from participation to this study because his cardiac
function and performence will be evaluated in detail and if decreased possible
underlying factors can be identified.
Furthermore, the results of this study will help to further rfine the surgical
approach to patients born with PA-IVS.