Characterization of a previously unrecognized clinical phenomenon: Delayed shock after cardiac implantable electronic device extraction.

BACKGROUND: Transvenous lead extraction remains a challenging procedure with inherent risk and associated complications.

OBJECTIVE: We sought to characterize and evaluate predictors of delayed shock after transvenous lead extraction with no intraprocedural complications.

METHODS: We retrospectively analyzed data of 217 consecutive patients who underwent extraction between 2010 and 2015. The primary end point was sudden onset of shock more than 4 hours after the completion of the procedure. Shock was defined as at least 30 minutes of persistent hypotension, necessitating vasopressors. Patients with mechanical or hemorrhagic shock were excluded.

RESULTS: Seventeen patients (9%) developed delayed shock during the first 24 hours. Reasons for shock were sepsis (47%) or no apparent cause (53%). In multivariate analysis, patients with delayed shock had significantly lower glomerular filtration rate (median estimated glomerular filtration rate 53 mL/min vs 73 mL/min; P = .001), had more signs of systemic infection before extraction (fever, bacteremia, and leukocytosis; P < .05), and had more lead/tip remnants (29% vs 3%; P < .001). Patients presenting with delayed shock had significantly higher mortality rates at 1-year follow-up (10 [59%] vs 40 [23%], respectively; P < .01). Multivariate analysis adjusted for 1-year mortality risk was 114% higher (hazard ratio 2.14; 95% confidence interval 1.02-4.47; P < .05) in patients presenting with delayed shock.

CONCLUSION: We describe a previously unrecognized clinical phenomenon of delayed shock developing after extraction. Patients with predictors of this condition at baseline should be identified and followed up closely. Even with prompt treatment, long-term mortality rates remain high.