Major infections after PCI, CABG do not affect very long-term survival

While major infections worsen 5-year survival after percutaneous coronary intervention (PCI) or coronary artery bypass graft (CABG) for coronary artery disease (CAD), no detrimental effects on mortality are observed thereafter, suggesting that its impact subsides after 5 years, a recent study has found.

The researchers conducted a subgroup analysis of the SYNTAX Extended Survival trial, enrolling 140 CAD patients who had had major postprocedure infections but survived until 5 years. Their estimated mortality rate for the next 5 years was calculated using the Kaplan-Meier method and compared against that of patients who had no major postprocedural infections.

A total of 229 deaths occurred from 5 to 10 years after intervention, yielding a mortality rate of 15.6 percent. Twenty-seven of these deaths occurred in the major infection group, while 202 were recorded in no-infection controls (19.8 percent vs 15.1 percent).

Adjusted Cox proportional hazards analysis found no difference in risk between groups (hazard ratio [HR], 1.10, 95 percent confidence interval [CI], 0.62–1.96; p=0.740). There was also no significant interaction of the treatment arm (p=0.564), suggesting that such a trend was consistent in PCI and CABG patients.

Subsequent exploratory analysis showed that patients who developed periprocedural major infections had a higher 10-year mortality risk than no-infection comparators, though the effect fell short of significance (30.8 percent vs 24.5 percent; HR, 1.36, 95 percent CI, 0.99–1.88; p=0.058).

“In other words, patients who had experienced major periprocedural infections but had been cured do not necessarily require an intensive long-term follow-up and could receive the local standard of care,” the researchers said.

“Due to the limited number of patients with a history of major periprocedural infections in the current study, this hypothesis should be confirmed in large pooled data, ideally with very long-term follow-up,” they added.