Role of proinflammatory markers and NT-proBNP in patients with an implantable cardioverter-defibrillator and an electrical storm.

Abstract Background Several studies have attempted to identify risk factors for the development of an electrical storm (ES), which is defined as ⩾3 separate ventricular tachyarrhythmic (VT/VF) events, but in the majority of studies no triggers have been found. However, little is known about the role of inflammation and NT-proBNP in patients with ES. The aim of this study was therefore to assess the relationship of Interleukin-6 (IL-6), high-sensitivity C-reactive protein (hs-CRP) and NT-proBNP serum concentrations in ICD-patients with or without single spontaneous ventricular tachyarrhythmic events (VT/VF) and in ES. Methods Markers were determined in 51 patients without ICD-intervention, in 15 ICD-patients with single VT/VF-episodes during 9-months follow-up and in 20 ICD-patients with ES (blood sampling performed within 60 min after fulfilling ES criteria). VT/VF-episodes were analysed by stored ICD-electrograms. Results All patients had idiopathic dilated cardiomyopathy ( n  = 23) or coronary artery disease ( n  = 63). Patients with ES revealed significantly higher mean serum concentrations of all markers (IL-6 15.19 ± 10.34 pg/mL, hs-CRP 20.12 ± 14.4 mg/L, NT-proBNP 4799 ± 4596 pg/mL) compared to baseline values of patients with single VT/VF-events during follow-up (IL-6 8.37 ± 5.8 pg/mL ( p  = 0.03), hs-CRP 4.7 ± 5.3 mg/dL ( p p  = 0.04)) and compared to baseline values of ICD-patients without device intervention (IL-6 4.62 ± 3.66 pg/mL ( p p p p  = 0.04), hs-CRP 19.07 ± 16.07 vs. 6.5 ± 3.9 mg/L ( p  = 0.02), NT-proBNP 4218 ± 2561 vs. 2099 ± 1279 pg/mL ( p  = 0.03)). Conclusions Electrical storm is associated with significantly elevated IL-6, hs-CRP and NT-proBNP serum concentrations in ICD-patients with structural heart disease. Thus, ES may be triggered by proinflammatory activity. Combined intraindividual elevation of determined markers might help to identify patients at risk of impending electrical storm.