Latent Clinical Outcomes of Appropriate and Inappropriate ICD Shocks

Abstract

Introduction: Despite the proven survival benefits, ICD (implantable cardioverter defibrillator) therapy has still some drawbacks. It is clearly known that inappropriate shocks increase mortality however, randomized controlled trials showed us that appropriate shocks might also increase mortality. Left untreated, ventricular arrhythmias are known to be fatal and in this case ICD shock therapy is life-saving so it is appropriate to assess the effects of ATP (Antitachycardial Pacing) therapy and shock separately. The aim of our study is to determine the effects of inappropriate and appropriate shocks in a population of ICD implanted patients.Patients and Methods: We retrospectively screened ICD implanted patients between January 2003 and December 2013 in our department. Additionally, patients were called by telephone and parameters such as survival and rehospitalization were updated. During the retrospective follow-up, the occurrence of inappropriate-appropriate ICD shocks and mortality causes were noted. Characteristics of patients suffering from shocks were also investigated. Results: A total of 260 ICD implanted patients were included in the study. 40 of them experienced inappropriate shocks (defined as at least one inappropriate shock, not any appropriate shocks). 69 patients experienced appropriate shocks (defined as at least one appropriate shock, not inoppropriate shocks). Retrospective mean follow up period was 49 months, minimum follow up period was 6 months. Among 40 patients experiencing inappropriate shocks 13 deaths (32.5%) occured (p=0.039). Among 69 patients experiencing appropriate shocks 24 deaths (34.8%) occured (p=0.001).Conclusion: In a large cohort of ICD patients, inappropriate and appropriate shocks were common. The most important finding was the association between appropriate shocks and mortality.

Keywords

• Implantable Cardioverter-Defibrillators, Heart Failure, Cardiac Arrhythmias

Uygun ve Uygunsuz ICD Şoklamalarının Latent Klinik Sonuçları

Abstract

Giriş: Kanıtlanmış faydalarına rağmen, ICD (implantable cardioverter defibrillator) tedavisinin halen bazı dezavantajları bulunmaktadır. Net olarak bilinmektedir ki, uygunsuz ICD şoklamaları mortaliteyi arttırmaktadır ancak randomize kontrollü klinik çalışmalar bize aynı zamanda uygun şoklamaların da mortaliteyi arttırabildiğini göstermiştir. Tedavi edilmediği takdirde ventriküler aritmiler ölümcüldür ve bu durumda ICD tedavisinin yaşam kurtarıcı olduğu bilinmektedir. Bu nedenle ATP (Antitachycardial Pacing) ve şoklama terapilerinin etkilerini ayrı ayrı değerlendirmek uygun olacaktır. Çalışmamızın amacı ICD implante edilmiş olan bir grup hastada uygun ve uygunsuz ICD şoklamalarının oluşturdukları klinik sonuçların saptanmasıdır.Hastalar ve Yöntem: Retrospektif olarak kliniğimizde Ocak 2003 ve Aralık 2013 tarihleri arasında ICD implante edilmiş olan hastaları tarandı. Ek olarak, bahsi geçen hastalar telefon ile arandı ve sağkalım, tekrarlayan hastaneye yatış gibi parametreler güncellendi. Retrospektif tarama sırasında uygun-uygunsuz şoklamaların varlığı ve mortalite nedenleri not edildi. Şoklama yaşayan hastaların özellikleri dikkatli bir şekilde araştırıldı. Bulgular: Çalışmaya toplamda 260 hasta dahil edildi. 40 tanesinde uygunsuz şoklama (uygun şoklama olmaksızın en az bir adet uygunsuz şoklama) ve 69 tanesinde uygun şoklama (uygunsuz şoklama olmaksızın en az bir adet uygun şoklama) saptandı. Retrospektif ortalama takip süresi 49 ay, minimum takip süresi 6 ay idi. Uygunsuz şoklama yaşayan 40 hastadan 13 tanesi (%32.5) exitus oldu (p=0.039). Uygun şoklama yaşayan 69 hastadan 24 tanesi (%34.8) exitus oldu (p=0.001).Sonuç: Geniş bir ICD implante edilmiş hasta serisinde, uygun ve uygunsuz ICD şoklamaları yaygın olarak izlendi. En önemli bulgu uygun şoklamalar ve mortalite arasında izlenen kuvvetli ilişki idi.

Keywords

• İmplante Edilebilir Kardiovertör-Defibrilatörler, Kalp Yetmezliği, Kardiak Aritmiler

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