Person:

McMullan, Ciaran Joseph

Objectives

We aimed to identify the frequency, pattern, and prognostic significance of left ventricular (LV) late gadolinium enhancement (LGE) in patients with atrial fibrillation (AF).

Background

There are limited data on the presence, pattern, and prognostic significance of LV myocardial fibrosis in patients with AF. Late gadolinium enhancement during cardiac magnetic resonance (CMR) is a marker for myocardial fibrosis.

Methods

We studied a consecutive group of 664 patients without known prior myocardial infarction being referred for radiofrequency ablation of AF. CMR was requested to assess pulmonary venous anatomy.

Results

Overall, 73% were male, with an average age of 56 years, and an ejection fraction of 55±10%. Left ventricular LGE was found in 88 patients (13%). The endpoint was all-cause mortality, and in this cohort we observed 68 deaths over a median follow-up period of 42 months. On univariable analysis, age (HR 1.05, CI 1.03–1.08, LRχ2 15.2, p=0.0001), diabetes (HR 2.39, CI 1.41–4.09, LRχ210.3, p=0.001), a history of heart failure (HR 1.78, CI 1.09–2.91, LRχ2 5.37, p=0.02), left atrial dimension (HR 1.04, CI 1.01–1.08, LRχ2 6.47, p=0.01), presence of LGE (HR 5.08, CI 3.08–8.36, LRχ2 28.8, p<0.0001), and LGE extent (HR 1.15, CI 1.10–1.21, LRχ2 35.6, p<0.0001) provided the strongest association with mortality. The mortality rate was 8.1% per patient-years in patients with LGE vs. 2.3% patients without LGE. In the best overall multivariable model for mortality, age and the extent of LGE were independent predictors of mortality. Indeed, each 1% increase in LGE associated with a 15% increased risk of death.

Conclusions

In patients with AF, LV LGE is a frequent finding and is a powerful predictor of mortality.