Incidence, Risk Factors, and Outcome of Life-Threatening Ventricular Arrhythmias in Giant Cell Myocarditis

Abstract

Background-Ventricular tachyarrhythmias are characteristic of giant cell myocarditis, but their true incidence, predictors, and outcome are unknown. Methods and Results-Our work involved 51 patients with giant cell myocarditis (35 women) aged 52±12 years. Their medical records were reviewed for history, results of laboratory and imaging studies, and occurrence of serious cardiac events, including life-threatening ventricular tachyarrhythmias. Sudden cardiac death (fatal or aborted) was the primary end point of our analyses, whereas the composite of sudden cardiac death and ventricular tachycardia requiring treatment constituted the secondary end point. Giant cell myocarditis presented as nonfatal ventricular tachyarrhythmia in 10 patients and as a fatal cardiac arrest in 1 patient. Overall, 14 of 50 patients suffered a sudden cardiac death during followup, with a cumulative incidence of 22% at 1 year and 26% at 5 years from presentation. The composite incidence of sudden cardiac death or ventricular tachycardia was 41% at 1 year and 55% at 5 years. The incidence of arrhythmias was associated with high plasma concentrations of troponin-T and N-terminal brain natriuretic propeptide, as well as with moderate-to-severe fibrosis on myocardial biopsy and history of ventricular tachyarrhythmias at presentation (P<0.05 for all). An intracardiac cardioverter defibrillator was implanted in 31 patients, of whom 17 had altogether 114 appropriate antiarrhythmic therapies by the device and none suffered an arrhythmic death. Conclusions-In giant cell myocarditis, the risk of life-threatening ventricular arrhythmias exceeds 50% at 5 years from admission, being related to the presenting clinical manifestation and markers of myocardial injury and scarring.(Circ Arrhythm Electrophysiol. 2016;9:e004559.

Fulminant giant-cell myocarditis on mechanical circulatory support: Management and outcomes of a French multicentre cohort

“…Second, almost half of our patients experienced an electrical storm before MCS implantation, corroborating the strong impact of arrhythmias on prognosis in these severe GCMs. Recently, 22% of a 51-patient GCM cohort had initial sustained VT or VF causing cardiac arrest, which markedly enhanced the risk of long-term life-threatening arrhythmias (up to 50% at 5 years) [28].…”

Therapeutic implications of a combined diagnostic workup including endomyocardial biopsy in an all‐comer population of patients with heart failure: a retrospective analysis

“…A specific antiviral therapy or immunosuppression was initiated only when standard therapy failed. In some cases, as in giant cell myocarditis, the immediate initiation of a disease‐modifying therapy is of vital importance for the patient and is only possible after the confirmation of the diagnosis through EMB . As it is hard to estimate in advance, if the underlying cause of cardiomyopathy is one that requires immediate treatment, it is more preferable to carry out an EMB too early than to withhold therapy in a patient who requires it immediately.…”

“…In some cases, as in giant cell myocarditis, the immediate initiation of a disease-modifying therapy is of vital importance for the patient and is only possible after the confirmation of the diagnosis through EMB. 43,44 As it is hard to estimate in advance, if the underlying cause of cardiomyopathy is one that requires immediate treatment, it is more preferable to carry out an EMB too early than to withhold therapy in a patient who requires it immediately. With this consideration, the rate of initiating an anti-inflammatory or antiviral therapy might have even been higher than 12%.…”

Giant-cell myocarditis - A case report and a brief review

“…Samotná terapie kortikosteroidy nepřináší prodloužení přežití a navzdory kombinované léčbě u třetiny nemocných lze v průběhu prvního roku předpokládat progresi onemocnění vyžadující srdeční transplantaci. Mimoto existuje i významné riziko setrvalých komorových tachykardií/komorové fi brilace či náhlé srdeční smrti, jež dosahuje v publikovaných souborech kumulativní incidence až 69 % [15]. Z tohoto důvodu je na rozdíl od lymfocytární myokarditidy implantace kardioverteru-defi brilátoru obecně doporučována.…”