Impact of Anxiety on Cardiac Substrate Modification in Women With Atrial Fibrillation Undergoing Catheter Ablation

Hypothesis: High level of anxiety promotes remodeling of cardiac substrate via persistent inflammation, resulting in an increase in the prevalence of left atrial scar and non-pulmonary vein (non-PV) triggers in women with AF.

Rationale: Anxiety is generally defined as a psycho-biological emotional state or reaction that consists of unpleasant feelings of tension, apprehension, nervousness, and worry, and activation of the autonomic nervous system. This disorder is typically more common in women than men. There is considerable evidence to suggest close interactions between anxiety and inflammation and inflammation and AF.

Earlier studies have documented strong association between anxiety and inflammation as shown by high levels of inflammatory biomarkers such as C-reactive protein (CRP), total white blood cell (TWBC) count, fibrinogen and interleukin-6 in patients with anxiety. Chronic inflammation results in structural remodeling of the atrial architecture such as fibrotic changes that supports genesis and perpetuation of AF. In cardiac fibrosis, myocytes coupled with fibroblasts can undergo early depolarization resulting in increased ectopic beats and repetitive firing leading to the origin of non-pulmonary vein (non-PV) drivers. Left atrial scar is another known consequence of cardiac fibrosis. Therefore, it is prudent to hypothesize that high level of anxiety for prolonged period results in structural remodeling of cardiac substrates evidenced by increased prevalence of left atrial scar and non-PV triggers in female patients with paroxysmal and persistent AF.

Scar and non-PV triggers are known independent predictors of arrhythmia recurrence in AF patients undergoing catheter ablation. Recurrences of AF, despite complete PV disconnection, strongly suggest an important possible role of these foci in serving as a source for the persistence of this arrhythmia. Altered conduction and barriers resulting from the atrial scar form the critical circuits for intra-atrial re-entry that promotes AF persistence.

Recent progress in technology and knowledge have provided better understanding and allowed the electrophysiologists to improve on the ablation procedure in order to make it more safe and effective. However, there are still scores of unanswered questions in this relatively young research domain, one of which is if anxiety impacts cardiac substrate remodeling that potentially influences ablation-outcome. Also, of note, anxiety affects how patients perceive their illness, particularly for women, and influence healthcare utilization and economic burden. Therefore, if the role of anxiety would be ascertained, timely intervention of the same would lead to improvement in the success rate of the ablation therapy in females that highly dominate this subset of AF population.