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Background Predictors of atrial fibrillation (AF) recurrence after catheter ablation (CA) are not fully defined. We hypothesized that 2D left atrial (LA) regional strain maps would help identify abnormal atrial substrate that increases susceptibility to AF recurrence post-CA. Methods and Results Sixty-three patients (63±10 years, 60% male) underwent CA for symptomatic paroxysmal (75%) or persistent (25%) AF. Baseline LA mechanical function determined using speckle tracking echocardiography was compared between those with AF recurrence (AFR) and no recurrence post-CA. Bi-dimensional global and regional maps of LA wall velocity, strain, and strain rate (SR) were obtained during end ejection and early diastole. After 18±12 months of follow-up, 34 patients were free of AFR post-CA. There were no differences in clinical characteristics, LA and LV volumes, and Doppler estimates of LV diastolic function and filling pressures at baseline between patients with recurrent AF and those that maintained sinus rhythm. However, the LA emptying fraction (55±17% vs. 64±14%, p=0.04), global and regional systolic and diastolic strains, SR, and velocities were reduced in patients with recurrent AF. There was marked attenuation of peak LA lateral wall longitudinal strain (LS; 11±7% vs. 20±14%, p=0.007) and SR (0.9±0.4 vs. 1.3±0.6 s−1, p=0.01). Multivariate analysis revealed lateral wall LS (odds ratio=1.15, 95% CI=1.02–1.28, p=0.01) as an independent predictor of AFR. Conclusions Regional LA lateral wall LS is a pre-procedural determinant of AFR in patients undergoing CA, independent of LA enlargement. Characterization of atrial myocardial tissue properties by speckle tracking echo may aid the appropriate selection of adjunctive strategies and prognostication of patients undergoing CA.

BackgroundAnalysis of left ventricular (LV) mechanical dyssynchrony may provide incremental prognostic information regarding cardiac resynchronization therapy (CRT) response in addition to QRS width alone. Our objective was to quantify LV dyssynchrony using feature tracking post processing of routine cardiovascular magnetic resonance (CMR) cine acquisitions (FT-CMR) in comparison to speckle tracking echocardiography.MethodsWe studied 72 consecutive patients who had both steady-state free precession CMR and echocardiography. Mid-LV short axis CMR cines were analyzed using FT-CMR software and compared with echocardiographic speckle tracking radial dyssynchrony (time difference between the anteroseptal and posterior wall peak strain).ResultsRadial dyssynchrony analysis was possible by FT-CMR in all patients, and in 67 (93%) by echocardiography. Dyssynchrony by FT-CMR and speckle tracking showed limits of agreement of strain delays of ± 84 ms. These were large (up to 100% or more) relative to the small mean delays measured in more synchronous patients, but acceptable (mainly <25%) in those with mean delays of >200 ms. Radial dyssynchrony was significantly greater in wide QRS patients than narrow QRS patients by both FT-CMR (radial strain delay 230 ± 94 vs. 77 ± 92* ms) and speckle tracking (radial strain delay 242 ± 101 vs. 75 ± 88* ms, all *p < 0.001).ConclusionsFT-CMR delivered measurements of radial dyssynchrony from CMR cine acquisitions which, at least for the patients with more marked dyssynchrony, showed reasonable agreement with those from speckle tracking echocardiography. The clinical usefulness of the method, for example in predicting prognosis in CRT patients, remains to be investigated.

Using TVI, HD patients demonstrate myocardial dysfunction, which is found less frequently when using conventional echocardiography. The systolic function seems to be impaired by high plasma levels of phosphate and an increased Ca x P product. One single session of HD improved systolic function as indicated by increases in IVCv, PSv and SR. Further studies are needed to clarify if this effect of HD is due to the acute removal of fluid, the removal of solutes or both.

This study demonstrated significant biventricular diastolic and biatrial systolic and diastolic dysfunction in MFS patients. Our findings suggest that MFS affects diastolic function independently. Diastolic abnormalities could be attributed to fibrillin-1 deficiency and dysregulation of transforming growth factor-beta activity in the cardiac extracellular matrix.

Background: The appropriate evaluation of atrial electrical function is only possible by means of invasive electrophysiology techniques, which are expensive and therefore not suitable for widespread use. Mechanical atrial function is mainly determined from atrial volumes and volume-derived indices that are load-dependent, time-consuming and difficult to reproduce because they are observer-dependent.

Our study showed a uniform reduction in biventricular deformation in MFS. These findings suggest that assessment of myocardial function using advanced echocardiographic techniques could be more accurate in MFS patient evaluation than conventional echocardiography alone.