The impact of shock therapy on depression development and remote prognosis in cardiac resynchronization therapy recipients.

BACKGROUND

The aim of this study was to assess the incidence and clinical significance of depression in patients with cardiac resynchronization therapy with an implantable cardioverter-defibrillator (CRT-D). The study was also to evaluate the impact of shock therapy on depression development and long-term prognosis.

METHODS

The prospective study encompassed 396 consecutive heart failure (HF) patients implanted with CRT-D. All patients completed the Beck Depression Inventory (BDI-II) and underwent a psychiatric examination at baseline. 221 patients free of depressive symptoms at baseline were included into the final analysis. The assessment of psychiatric status was routinely repeated every 6 months as well as after the shock delivery. The primary outcome was a composite endpoint of death or hospitalization for HF.

RESULTS

During long-term observation (median 37.1 months) 52 (23.5%) patients suffered from an implantable cardioverter-defibrillator (ICD) shock, whereas 48 (21.8%) subjects developed depression. The incidence of new-onset depression was significantly higher in patients after shock delivery (Shock Group), CRT non-responders and subjects with atrial fibrillation. The risk for a composite endpoint was higher in the Shock Group than subjects without an ICD intervention: 57.7% vs. 25.4% and in patients with new-onset depression compared to the population free of this disorder: 62.5% vs. 24.9% (all p < 0.001). New-onset depression (HR 1.7) and an ICD shock (HR 2.1) were strong independent predictors of poor prognosis.

CONCLUSIONS

Depression is a common mental disorder in CRT-D recipients, that adversely affects long-term prognosis. Subjects suffering from ICD shocks and those with HF progression are at higher risk of experiencing depressive symptoms.