Long-Term Changes in the Biomarkers of Left Atrial Fibrosis after Pulmonary Vein Isolation for Paroxysmal and Persistent Atrial Fibrillation

TL;DR

This study examines how biomarkers of heart tissue changes respond to a treatment for irregular heartbeats and finds they don't predict treatment success.

Contribution

The study provides new insights into biomarker behavior after ablation in patients with structurally normal hearts.

Findings

Biomarker levels were not associated with AF recurrence after ablation.

Caspase-3, Galectin-3, and Cathepsin L decreased significantly over 3 years.

Caspase-3 levels correlated with left atrial size in patients with AF recurrence.

Abstract

Atrial fibrillation (AF) is accompanied by inflammation and
fibrosis to variable extent. The biomarkers of fibrosis were measured in patients
with different forms of AF and cardiac status. Herein, we assessed the
associations of the baseline concentrations of different biomarkers with the
long-term success of pulmonary vein isolation (PVI) in patients with a
structurally normal heart. Furthermore, we compared biomarker levels before and 3
years after ablation to gain further insights into the AF mechanism.

Patients, undergoing PVI for paroxysmal/persistent AF were
enrolled prospectively. Blood samples were obtained 24 hours before and 3 years
after ablation. Serum cancer antigen 125 (CA-125), plasma Caspase-3, Galectin-3
and Cathepsin L concentrations were measured. Follow-up visits every 6 months
included 12-lead electrocardiogram, 24-hour Holter, trans-telephonic monitoring
as well as transthoracic echocardiography after ablation. Biomarker levels, left
ventricular ejection fraction and left atrial (LA) diameters at baseline and at
the 3-year follow-up were compared in patients with versus without AF recurrence.

A total of 63 patients were enrolled (23 women; age 61.4
(± 8.8) years). The acute isolation of all pulmonary veins was achieved in
all patients. During a mean follow-up of 36.3 ± 6.3 months, AF recurrence
was demonstrated in 26 (41.3%) patients. No significant differences were
demonstrated in the levels of CA-125, Galectin-3, Caspase-3 and Cathepsin L pre-
and post-ablation in patients with versus without AF recurrence. A significant
decrease was detected in the concentrations of Caspase-3, Galectin-3 and
Cathepsin L during follow-up with no difference in patients with versus without
AF recurrence. A positive correlation was found between Caspase-3 levels and LA
diameters in the AF recurrence group both before (r = 0.477; p = 0.018)
and after the procedure (r = 0.533; p = 0.019).

Our results demonstrated that the levels of CA-125, Caspase-3, Cathepsin L and
Galectin-3 are not associated with AF recurrence after PVI in patients with a
structurally normal heart and mainly paroxysmal AF. Except for CA-125, all the
other biomarkers demonstrated a significant decrease during a 3-year follow-up
post-ablation. Furthermore, Caspase-3 levels demonstrated a positive correlation
with LA dimensions in patients with AF recurrence.

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