Key result
Phenylephrine is linked to ~24% lower mortality vs norepinephrine in AF and shock.
Why the study?
Atrial fibrillation complicated by shock has high mortality requiring vasopressor support, but the relative efficacy of norepinephrine versus phenylephrine in this population is uncertain.
Does phenylephrine improve survival compared to norepinephrine in adult patients with atrial fibrillation complicated by shock?
Cohort (n=45,545)
Yes
Does phenylephrine improve survival compared to norepinephrine in adult patients with atrial fibrillation complicated by shock?
Effect estimate: HR 0.756 (95% CI 0.719-0.795)
Absolute Event Rate: 42.153% vs 49.324%
p-value: p=<0.001
In a large retrospective cohort of patients with atrial fibrillation and shock, phenylephrine use was associated with significantly lower all-cause mortality compared to norepinephrine.
Background Atrial fibrillation complicated by shock represents a high mortality condition and requires adequate support with vasopressors. While both norepinephrine and phenylephrine are the vasopressors of choice in shock, their relative efficacy in this population is uncertain. This study aimed to evaluate the mortality benefit of using norepinephrine and phenylephrine in this high risk population and to bridge a critical knowledge gap. Methods We conducted a retrospective cohort study on the TriNetX Research Network across 112 healthcare organizations. We included adult patients (≥ 18 years age), with Atrial fibrillation (ICD-10: I48) and shock (including cardiogenic shock [R57.0], hypovolemic shock [R57.1], other shock [R57.8], unspecified shock [R57.9], septic shock [R65.21], or shock without trauma [785.5]) who received treatment with phenylephrine (n = 6,869) or norepinephrine(n = 38,676) within 1 day of diagnosis. 1:1 propensity score matching was performed to match for demographics, diagnoses, procedures, medications, vitals, lab values, genomics and visits, yielding 6,652 patients per group. Primary outcome studied was all-cause mortality, analyzed using risk analysis and Kaplan-Meier survival analysis. Results After propensity matching, norepinephrine was associated with significantly higher mortality (42.153% vs 49.324%; risk difference -7.171%, 95% CI: -8.859 to -5.482, p<0.0001). The risk ratio was 0.855 (95% CI: 0.823 to 0.887) and odds ratio was 0.749 (95% CI: 0.699-0.802). Mean follow-up was 675 days for phenylephrine versus 560 days for norepinephrine. Kaplan-Meier survival analysis demonstrated better survival probability for norepinephrine (30.65% vs 18.85%; log-rank p<0.001), with a hazard ratio of 0.756 (95% CI: 0.719 to 0.795).Conclusion Among patients with atrial fibrillation and shock, Phenylephrine showed significant survival benefit compared to norepinephrine, as evidenced by findings of Kaplan-Meier survival analysis. These observational findings need to be validated by prospective studies and randomized controlled trials. Further research is indicated to optimize vasopressor selection in this population. This abstract is funded by: None
No takes yet. Share an insight, caveat, or question.
Gopikrishnan et al. (2026) conducted a cohort in Atrial fibrillation complicated by shock (n=45,545). Phenylephrine vs. Norepinephrine was evaluated on All-cause mortality (HR 0.756, 95% CI 0.719-0.795, p=<0.001). Phenylephrine was associated with lower all-cause mortality compared to norepinephrine in patients with atrial fibrillation and shock (42.15% vs 49.32%; HR 0.756; 95% CI 0.719-0.795; P<0.001).
Synapse has enriched 5 closely related papers on similar clinical questions. Consider them for comparative context: