The impact of atrial mechanical function on age-dependent presentation of neurocardiogenic syncope

Low left atrial volume is an independent predictor of persistent hypotension after carotid artery stenting

BACKGROUND

Persistent hypotension (PH) after carotid artery stenting (CAS) is a relatively common complication; however, it is unclear which patients are more likely to experience this phenomenon. Recently, lower left atrial (LA) volume was associated with vasovagal syncope, which has a similar neurological mechanism to hypotension after CAS. This study aimed to investigate whether LA volume can predict PH after CAS.

METHODS

This single center retrospective analysis used data from 316 patients who had undergone CAS between March 2013 and February 2021. After the exclusion of urgent CAS, 212 procedures (202 patients) with transthoracic echocardiograms were included. The procedures were divided among two groups according to the presence or absence of PH for more than 1 hour after CAS.

RESULTS

The mean age of the patients was 73.0±7.5 years. PH was observed during 52 (24.5%) procedures. The PH group exhibited a lower LA volume index (LAVI) than the no-PH group (29.7±9.1 vs 37.7±12.5 mL/m2, respectively; p<0.001). The area under the receiver operating characteristic curve was 0.716. The optimal cut-off value was 33.5 mL/m2 (sensitivity 0.750, specificity 0.625). Multiple logistic regression analysis showed that LAVI <33.5 mL/m2 was an independent predictor for PH after CAS (OR 4.950, 95% CI 2.190 to 11.200; p<0.001). Preoperative hydration was negatively associated with PH (OR 0.235, 95% CI, 0.070 to 0.794; p=0.020).

CONCLUSIONS

A lower LA volume can predict PH after CAS, and preoperative hydration may prevent PH after CAS.

Left atrial function evaluation by 2D speckle-tracking echocardiography in patients with vasovagal syncope

OBJECTIVES

Evidence indicates left atrial (LA) involvement in vasovagal syncope (VVS). The LA regulates left ventricular filling during the cardiac cycle. We aimed to assess LA function in patients with VVS by 2D speckle-tracking echocardiography.

METHODS

Sixty-nine consecutive patients with VVS were recruited. Based on the head-up tilt test (HUTT) results, the study population was divided into two groups: HUTT+ (n = 45) and HUTT- (n = 24). Fifty-one consecutive subjects were enrolled as the control group. LA myocardial deformation parameters were measured by 2D speckle-tracking echocardiography to evaluate LA function.

RESULTS

Maximal, minimal, and pre-P LA volumes were lower in patients with VVS. Strain and strain rate during reservoir, conduit, and contraction phases in VVS patients with HUTT+ or HUTT- were not statistically significantly different from those in the control group. Additionally, the volumetric parameters of LA function showed no difference in statistical significance between the three study groups.

CONCLUSIONS

While LA phasic function was not different between the two groups of VVS patients with HUTT+ or HUTT- and the control group, LA size during the three LA phases was smaller in patients with VVS.