Haozhu Chen

Left ventricular torsional deformation in patients undergoing transcatheter closure of secundum atrial septal defect

Left ventricular (LV) torsional deformation plays an important role with respect to LV ejection and filling. However, no data are available on the impact of overload relief on LV torsional deformation after transcatheter ASD closure. This study sought to evaluate LV twist and untwisting before and early after device closure of ASD using the speckle tracking imaging (STI). We acquired basal and apical LV short-axis ultrasound images in 30 asymptomatic patients (29 ± 9xa0years, 9 males) scheduled for percutaneous closure of an ASD before and 1-day after transcatheter ASD closure. All data were offline analyzed with Echopac 7.0 software. After transcatheter ASD closure, there was no significant difference in peak apical rotation and time to the peak (P > 0.05 for both). However, a significantly improved basal rotation was recorded, including significantly increased peak clockwise rotation (−7.1xa0±xa03.2° vs. −5.4xa0±xa02.9°, Pxa0=xa00.014), decreased initial counterclockwise rotation (2.0xa0±xa01.8° vs. 5.1xa0±xa03.2°, P < 0.001) and shortened time to peak clockwise rotation (105.5 ± 16.5% vs. 118.0 ± 18.5% of systolic period, P = 0.001). LV twist was significantly improved in patients with ASD after the device closure (16.1 ± 6.7° vs. 12.2 ± 6.3°, P = 0.001), whereas there was no significant difference in peak untwisting rate, time to the peak and untwisting during IVRT (P > 0.05 for all). In conclusion, LV systolic twist could be significantly improved but diastolic untwisting remained unchanged after transcatheter ASD closure. This improvement was mainly attributed to the improved LV basal rotation rather than the unchanged apical rotation.

Longitudinal two-dimensional strain rate imaging: a potential approach to predict the response to cardiac resynchronization therapy.

The purpose of our study was to test the usefulness of speckle-tracking two-dimensional echocardiography (in particular longitudinal strain and strain rate) in predicting the response to cardiac resynchronization therapy. The standard approach has been tissue Doppler-based echocardiographic imaging (TDI) has initially showed promising results in small clinical trials. However, recent larger, prospective randomized clinical trials (PROSPECT, ReTHINK) showed that TDI is inadequate to predict response from CRT in patients with heart failure. Altogether, these data suggest the need to identify alternative echocardiographic parameters to predict the response to CRT. We included 53 patients suffering from heart failure, who received CRT. TDI and two-dimensional speckle tracking imaging in addition to standard echocardiography were performed prior to CRT. The standard deviation of time to peak longitudinal strain in 12 LV segments (Tstrain-SD) and the standard deviation of time to the end of longitudinal systolic strain rate in six basal LV segments (Tsr-SD) were calculated. Standard echocardiography was performed 6xa0months after CRT. Patients were classified as echocardiographic responders if the LV end-systolic volume was reduced >15% compared with baseline volumes. No significant difference was seen in baseline Ts-SD, and Tstrain-SD between non-responders and responders. However, the Tsr-SD was much higher in responders than non-responders (95.9xa0±xa033.0% vs. 64.8xa0±xa039.6%, Pxa0<xa00.05), and it showed a sensitivity of 73% and specificity of 65% for the defined echocardiographic response using a cutoff value of 70.7xa0ms. Our study demonstrates that longitudinal two-dimensional strain rate imaging is a promising potential echocardiographic parameter to predict benefit from CRT in patients with heart failure. This hypothesis needs to be further tested in prospective randomized clinical trials.