Newborn with hydrops fetalis and a severe supraventricular arrhythmia

Abstract

A 33+1-week female baby was born by caesarean section for worsening hydrops fetalis (HF) detected in the third trimester of pregnancy. Prenatal ultrasound showed a moderate enlargement of the right heart sections with a mild tricuspid insufficiency, without tachycardia, polyhydramnios, placentamegaly, renal agenesis and oesophageal atresia. At delivery, she developed transient hypotonia and apnoea and received nasal continuous positive airway pressure. Physical examination showed tachypnoea (70 breaths/min) and a moderate generalised subcutaneous oedema. Chest X-ray showed a cardiothoracic index of 0.82. At 90 min of life, her heart rate was 200–250 per minute. An ECG showed a paroxysmal supraventricular tachycardia (PSVT) with narrow complexes (figure 1). Vagal manoeuvres and five boluses of adenosine (250 μg/kg/dose) were ineffective, but she responded to amiodarone. Echocardiography showed severe tricuspid insufficiency and dilated right cardiac chambers. The baby presented further transient PSVT episodes, but these gradually improved on amiodarone, hydrochlorothiazide, spironolactone and furosemide. A primitive tricuspid valvulopathy with heart failure secondary to PSVT was diagnosed. …