Pediatric patients with Long QT Syndrome – contemporary follow-up results – a single-center experience

Abstract

Aim: Long QT Syndrome (LQTS) is a genetically transmitted or acquired cardiac channelopathy that can lead to lethal arrhythmia and sudden cardiac death (SCD) in children. The clinical characteristics of LQTS are variable. We aimed to analyse the data of congenital and acquired LQTS patients that we follow and compare the results with the literature. Method: The data of LQTS patients were reviewed retrospectively via our recording system from January 2018 to August 2021. Results: There were 26 patients, of whom 21 (10 male) were congenital and five (four male) were acquired. The mean age in congenital patients was 9.83±4.24 years and it was 12.6±4.87 years in acquired ones. The most common presentation for congenital ones was asymptomatic patients (10/21). Others were seizures/epilepsy in four patients, stress induced syncope in two patients and cardiac arrest in two patients. The mean Schwartz score was 4.69±2.19 (1-8).Pathogenic mutations were detected in 11 cases. Patients with a QTC duration longer then 470 msn and symptoms had been given beta blocker therapy. One patient had been inserted implantable cardioverter-defibrillator.The most common symptom was bradycardia in acquired LQTS (5/5). The most common related causes were drugs and hypokalemia. Median follow-up time was 18.45±14.52 months (3-36). No patients died during the follow-up. Risk factors for major cardiac events were QTC value as >500 ms, T wave alternans, female gender, Jervell and Lange-Nielsen syndrome and hypokalemia. Conclusion: LQTS related SCD could be prevented by early evaluation if it’s come to mind in differential diagnosis. Treatment plan would be due to symptoms, risk factors and the type whether it was congenital or acquired.

Keywords

• Long QT Syndrome
• children
• arrhythmia
• genetic

Uzun QT sendromu ile takip edilen çocuk hastalar- Yakın yaman takip ve sonuçları- tek merkezli bir çalışma

Abstract

Amaç: Uzun QT Sendromu (UQTS) çocuklarda hayatı tehdit eden aritmilere ve ani kardiyak ölüme neden olabilen, genetik olarak geçen veya edinilmiş kardiyak bir kanalopati bozukluğudur. Klinik özellikler değişken olabilir. Bu çalışmada kliniğimizde takip ettiğimiz doğumsal (konjenital) ve edinilmiş UQTS olan hastaların verilerini inceleyerek literatürle karşılaştırmayı amaçladık. Yöntem: 2018 Ocak – 2021 Ağustos tarihleri arasında kliniğimizde UQTS tanısı alarak takip edilen hastaların verilerini bilgisayar ve dosya sistemi üzerinden geriye dönük olarak taradık. Bulgular: UQTS tanısı alan 26 hasta tespit edildi. Bunların 21’i (10 erkek) doğumsal, beşi (dört erkek) edinilmiş UQTS idi. Doğumsal UQTS’de ortalama yaş 9.83±4.24 yıl iken edinilmişte 12.6±4.87 yıldı. Doğumsal tipte en sık asemptomatik vakalar vardı (10/21). Bunu dört vakada nöbet/epilepsi, iki vakada ise stresle bayılma takip etmekteydi. İki hasta ise kardiyak arrest ile acile gelmişti. Ortalama Schwartz skoru 4.69±2.19 (1-8) idi. 11 hastada patojenik mutasyon tespit edildi. Semptomatik olan ve QTC 470 msn olan her hastaya beta blokör tedavi başlandı. İzlemde bir hastaya implante kardiyoverter-defibrilatör (ICD) takıldı. Edinilmiş UQTS’de en sık semptom bradikardi idi (5/5). Torsades de Pointes (TdP) olup tedavi gerektiren bir hasta oldu. En sık neden ilaçlar ve hipokalemi idi. Tüm hastalar ortalama 18.45±14.52 ay (3-36 ay) takip edildiler ve bu süreçte ölen hasta olmadı. Major kardiyak olaylar ve semptomlar göz önüne alındığında T dalga alternansı, QTC>500 msn olması, kız cinsiyet ve Jervell Lange-Nielsen Sendromu ile hipokalemi önemli risk faktörleri olarak sayıldılar. Sonuç: UQTS’nin ayırıcı tanıda akılda tutulması ve hastalığın erken tanısıyla ani kardiyak ölüm önlenebilir. Hastaların semptom, risk durumları ve doğumsal veya edinsel UQTS olmasına göre tedavi planı değişecektir.

Keywords

• Uzun QT sendromu
• çocuklar
• aritmi
• genetik

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