Clinical & Neurohormonal Predictors of Outcome after Electrical Cardioversion for Atrial Fibrillation

Atrial fibrillation (AF) is one of the most challenging disorders in clinical cardiology affecting 0.4-1% of persons in the general population and increasing with age. It is associated with an increased risk of stroke, heart failure and all-cause mortality and places a considerable strain on health budgets with hospitalization being the major cost driver. Its management consists of either ventricular rate control combined with anticoagulation, or attempts at restoring sinus rhythm which offers more optimal cardiac performance and potential freedom from anticoagulation. This thesis examines the potential role of clinical and neurohormonal markers when formalising management plans for patients with atrial fibrillation (AF). Chapter 1: Provides a literature review, AF classifications and principles of cardioversion. Chapter 2: Covers the Methods employed in conducting the studies research documented in this Thesis. Chapter 3: Documents outcomes and their predictors in a retrospective cohort study (December 2000 – December 2002) of patients coming forward for urgent and elective electrical cardioversion for AF in Canterbury. This chapter identified the number of shocks as a new predictor, and confirmed the role of some of the previously identified predictors, of post cardioversion rhythm outcome in patients with AF. Chapter 4: Documents rhythm outcome and predictors thereof in a prospectively recruited cohort of patients undergoing electrical cardioversion for AF (October 2003 – October 2009). The study has particular focus on the utility of neurohormonal markers. The findings in this cohort of patients confirmed the number of shocks needed at the time of cardioversion as a predictor of post cardioversion rhythm out come and identified the role of precardioversion N terminal brain natriuretic peptide (NBNP) and other neurohormones as predictors of post cardioversion rhythm outcome. Chapter 5: Provides Conclusions and suggests future studies