A rare cause of neonatal death: Long QT syndrome

Objective: Long QT syndrome is a rare syndrome with a high mortality rate in neonatal period. We report a newborn who was admitted to the outpatient clinic with complaints of cyanosis and breastfeeding difficulties, diagnosed as ventricular tachycardia due to long QT syndrome with no response to the treatment, and evaluate the diagnostic and therapeutic approaches in the context of current literature. Case: A newborn delivered at 41th week of pregnancy by cesarean delivery with a birth weight of 3460 grams was admitted to the emeregency outpatient clinic at postnatal seventh day with complaints of breastfeeding difficulty and cyanosis. Newborn was in a poor general condition with impaired peripherical circulation, with respiratory rate 80/min, heart rate 280/min, and oxygen saturation 60%. The newborn was intubated and admitted to the neonatal intensive care unit (NICU). Electrical cardioversion at 1 joule/kg was performed due to ventricular tachycardia (VT) detected at electrocardiography (ECG). After restoration of sinus rhythm, corrected QT (QTc) interval was measured as 0.53 sec. Echocardiography was performed and no structural cardiac anomaly was detected but severe mitral and tricuspid valve regurgitations were present and the ejection fraction (EF) was 30%. Because of recurrence of ventricular tachycardia (VT), synchronized cardioversion at 1 joule/ kg and 2 joule/kg were performed, followed by lidocaine therapy when no response was obtained. Due to the resistant VT, amiodarone, flecainide and esmolol were administered subsequently. Patient failed to respond to any antiarrhythmic treatment and was lost on day 3 of follow-up, after emerging ventricular fibrillation.
Conclusion: Long QT syndrome is a rare disease with high mortality in the newborn. Early diagnosis may help in terms of treatment but the main prognostic factors are the length of QT interval and the associated structural anomalies. Screening of newborns with risk factors by electrocardiography is controversial, but it may be considered in cases with determined risk factors. Also interventional procedures may be considered in severe cases resistant to medical treatments.

Yenidoðan mortalitesinin nadir bir nedeni: Uzun QT sendromu

Amaç: Uzun QT sendromu yenidoðan döneminde nadir görülen mortalitesi yüksek bir sendromdur. Olgumuz yenidoðan polikliniðine morarma ve emmede azalma þikayeti ile getirilen, uzun QT’ye baðlý venriküler taþikardisi geliþen ve tedaviye yanýt alýnamayan hastada gerçekleþtirilen tanýsal ve tedavisel yaklaþýmlarýn güncel literatür eþliðinde tartýþýlmasý amacýyla sunuldu.
Olgu: 41 gestasyonel haftasýnda sezaryen ile 3460 gr doðan bebek, postnatal 7. gününde emmede azalma ve morarma nedeniyle acil polikliniðimize getirildi. Genel durumu kötü, periferik dolaþýmý bozuk, solunum sayýsý 80/dk, kalp tepe atýmý ise 280/dk, oksijen saturasyonu %60 olan hasta entübe edilerek yenidoðan yoðun bakým ünitemize alýndý. Elektrokardiyogramýnda ventriküler taþikardisi saptanan (VT) hastaya 1j/kg kardiyoversiyon uygulandý. Sinüs ritmine döndükten sonra çekilen EKG’sinde düzeltilmiþ QT süresi 53 sn saptandý. Ekokardiyografisinde; yapýsal anomali izlenmemekle beraber ejeksiyon fraksiyonu %30, önemli mitral ve triküspit yetmezliði saptandý. VT’si devam eden hastaya 1 joule/kg ve 2 joule/kg’dan senkronize kardiyoversiyon yapýldý ve cevap alýnamayýnca lidokain tedavisi baþalndý. Ventriküler taþikardisi dirençli seyreden hastaya amiadoron, flekainid ve esmolol tedavileri sýrasýyla uygulandý. Antiaritmik tedavilere yanýt vermeyen hasta takibinin 3. gününde ventriküler fibrilasyona girerek kaybedildi.
Sonuç: Uzun QT sendromu yenidoðanda nadir görülen mortalitesi yüksek hastalýktýr. Erken taný tedavi açýsýndan yardýmcý olabilmekle beraber QT süresinin uzunluðu ve eþlik eden yapýsal anomaliler prognozu belirlemektedir. Risk faktörü olan yenidoðanlarýn EKG ile taranmasý tartýþmalýdýr. Hastalýðýn risk faktörleri belirlenmiþ vakalarda erken tanýmlanmasý için EKG çekilerek taranmasý ve medikal tedaviye dirençli aðýr olgularda giriþimsel metodolojinin uygulanmasý düþünülebilir.