New-onset atrial fibrillation and prognosis in nonagenarians after acute myocardial infarction

BACKGROUND: The influence of new-onset atrial fibrillation (AF) on the long-term prognosis of nonagenarians who survive acute myocardial infarction (AMI) has not been demonstrated. OBJECTIVE: Our aim was to study the association between new-onset AF and long-term prognosis of nonagenarians who survive AMI. METHODS: From a total of 96 patients aged ≥89 years admitted during a 5-year period, 64 (67 %) were discharged alive and are the focus of this study. RESULTS: Mean age was 91.0 ± 2.0 years, and 39 patients (61 %) were women. During admission, 9 patients (14 %) presented new-onset AF, 51 (80 %) did not present AF, and 4 (6 %) had chronic AF. During follow-up (mean 2.3 ± 2.6 years; 6.6 ± 3.6 years in survivors), 58 patients (91 %) died, including the 9 patients with new-onset AF. Cumulative survival at 6, 12, 18, 24, and 30 months was 68.3 %, 57.2 %, 49.2 %, 47.6 %, and 31.8 %, respectively. The only two independent predictors of mortality in the multivariate analysis were age (hazard ratio [HR] 1.14; 95 % confidence interval [CI] 1.01–1.28; p = 0.04) and new-onset AF (HR 2.3; 95 % CI 1.1–4.8; p = 0.02). CONCLUSION: New-onset AF is a marker of poor prognosis in nonagenarians who survive AMI.