Aims: Guidelines from the ESC and ACC/AHA recommend implantable cardioverter defibrillators (ICDs) be implanted in clinically indicated patients with a reasonable expectation of >1 year survival. Our study aimed to assess if selected clinical markers of organ dysfunction were associated with increased 1-year mortality despite ICD therapy.
Methods and results: We retrospectively studied 283 patients with de novo ICDs implanted for primary or secondary prevention in ischaemic heart disease and dilated cardiomyopathy. We investigated the association of the following clinical markers of organ dysfunction with 1 year mortality: liver dysfunction (aspartate transaminase/alanine transaminase ≥ 3× upper limit of normal or prothrombin time/international normalized ratio ≥ 1.5 in the absence of anticoagulation), respiratory dysfunction (recent mechanical ventilation within 3 months prior to ICD implant), renal dysfunction (creatinine ≥150 µmol/L or glomerular filtration rate ≤ 30 mL/min/1.73 m(2)), anaemia (Hb ≤ 100 g/L), and prior cerebral vascular injury. With no organ dysfunction, 1 year mortality was 1.9%. In the presence of a single organ dysfunction, mortality was increased to 14.3%. With two or more markers of organ dysfunction mortality was 38.1% at 1 year (log-rank test P < 0.001).
Conclusions: Clinical markers of liver dysfunction, recent mechanical ventilation, and renal impairment were independently associated with increased 1 year mortality. Presence of more than one clinical marker of organ dysfunction was associated with significantly increased risk of mortality in our study.