Echocardiography in Clinical Syndromes: Atrial Fibrillation

This abstract oral session, featuring presenters who were given 15 minutes to review their research, provided attendees with information on the E/e' ratio as a prognostic predictor in patients with atrial fibrillation (AF), the association between atrial and ventricular ECG findings and cardiac circulating biomarkers, stiffness of the left atrium, left atrial function as a predictor of first AF in older adults, and the mechanism of improvement of cardiac function in patients with AF. The studies are reviewed here.

The E/E' Ratio Is Prognostic Predictor in Patients with Atrial Fibrillation and Preserved Left Ventricular Systolic FunctionSung-Ji Park, Sung-A Chang, Jin-Oh Choi, Sang-Choi Lee, and Seung Woo Park, Samsung Medical Center, Seoul, Democratic People's Republic of Korea

Park explained that he and fellow researchers aimed to investigate the prognostic significance of the ratio of early diastolic mitral inflow velocity (E) and early diastolic mitral annular velocity (e')(E/e' ratio) "in patients with AF with preserved LV systolic function," as it has not been well investigated in patients with AF despite having been "reported to be useful in estimation of left ventricular filling pressure and predicting of prognosis in several diseases." After measuring ejection fraction by modified Simpson's method and measuring and averaging E and e' in five consecutive heart beats in 488 consecutive patients with AF and preserved LV systolic function, said Park, the researchers found that E/e' ratio is a "useful prognostic parameter in predicting cardiac events even in patients with AF and preserved LV systolic function."

Significant Association Between Atrial and Ventricular Echocardiographic Findings and Cardiac Circulating Biomarkers in Patients with a History of Atrial Fibrillation: Data from the GISSI-AF TrialLidia Staszewsky on behalf of the GISSI-AF Investigators

Because patients with AF may "present with remodeling of atrial and left ventricular chambers and activation of neurohormonal system, we evaluated the association between these two compensatory mechanisms in" patients with a history of AF, explained Staszewsky. The investigators observed a "strong and specific association between novel circulating cardiac biomarkers and the morphology of the left atrium" in a large number of patients (n=306) in sinus rhythm with a history of AF for the first time in a multicenter study and in this population.

Stiffness of the Left Atrium Relates to Left Ventricular Diastolic Dysfunction and Late Recurrence after Pulmonary Vein Isolation for Paroxysmal Atrial FibrillationTomoko Machino, Yoshihiro Seo, Tomoko Ishizu, Yukio Sekiguchi, Hiroshi Tada, and Kazatuka Aonuma, University of Tsukuba, Tsukuba, Japan

With evaluation of left atrial (LA) stiffness-previously not well examined due to difficulty in accurate evaluation-now achievable with reasonable accuracy "from direct LA pressure and LA strain obtained by speckle tracking imaging (STI) in patients undergoing pulmonary vein isolation (PVI) for" AF, this study, explained Seo, was designed to "measure LA stiffness of patients with AF and to evaluate whether LA stiffness correlates with cardiac function and morphology, serum natriuretic peptides, collagen markers, and late recurrence of AF after PVI." The investigators found an association between LA stiffness and collagen synthesis, LA dilation, and LV diastolic dysfunction. Additionally, they determined that "LA stiffness reflects progression of LA structural remodeling in patients" with paroxysmal AF and predicts late AF recurrence following PVI.

Left Atrial Function Is Superior to Volume for the Prediction of First Atrial Fibrillation in Older AdultsGustavo G. Blume, Marion E. Barnes, Paul M. Bastiansen, Patricia A. Pellikka, Bernard J. Gersh, James B. Seward, Stephen S. Cha, Kent R. Bailey, and Teresa S. Tsang, Mayo Clinic, Rochester, MN

The purpose for this research, stated Blume, was to study the comparative effectiveness of LA function for predicting first atrial fibrillation, previously unknown despite left atrial volume (LAV) being an independent predictor of first AF. Following studies on 577 people age 65 years or older, 65 of whom developed a new AF during an average 5 year, Blume, et al. found that total LA emptying fraction "is a robust predictor of first AF and compares favorably with LAV for such prediction."

The Mechanism of Improvement of Cardiac Function in PatientsJun Koyama, Hirohiko Motoki, Kazunori Aizawa, Toru Kawakami, Megumi Koshikawa, Hiroki Kasai, Atsushi Izawa, Takeshi Tomita, Yusuke Mi, Setsuo Kumazaki, and Uichi Ikeda, Shinshu University Graduate School of Medicine, Matsumoto, Japan

Koyama explained that this research team set out to test the hypothesis that pulmonary vein isolation (PVI) for AF with heart failure improves longitudinal left ventricular (LV) function, as the "precise mechanism of PVI for AF with HF is unknown," despite PVI having been reported to be effective in patients with AF and HF. Koyama's team found that after PVI in the studied patient population, improvements are seen in longitudinal LV dysfunction, changes that occur independent of improvements in atrial booster pump function.