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

Abstract

Background: The contribution of atrial and ventricular function in neurocardiogenic syncope (NCS) pathophysiology is elusive.Hypothesis: We assessed the influence of echocardiographic properties to the age of presentation and NCS recurrences. Methods:We assigned 124 patients with symptoms suggesting NCS, to those with syncope initiation at age <35 (group A, n = 56) and >35 years (group B, n = 68). Echocardiographic indices were measured before head-up tilt test (HUTT).Results: A total of 55 had positive HUTT (44%) with a trend favoring group A (p = .08). Group A exhibited lower left atrial (LA) volume index (17 ± 6 vs. 22 ± 11 ml/m 2 , p = .015), higher LA ejection fraction (69 ± 10 vs. 63 ± 11%, p = .008), LA peak strain (reservoir phase 41 ± 13 vs. 31 ± 14%, p = .001, contraction phase 27 ± 11 vs. 15 ± 10%, p < .001) and LA peak strain rate (reservoir phase 1.83 ± 1.04 vs. 1.36 ± 0.96 1/s, p = .012, conduit phase 2.36 ± 1.25 vs. 1.36 ± 0.78 1/s, p = .001). Group A showed smaller minimum right atrial (RA) volume, better RA systolic function, superior left ventricular diastolic indices, and lower filling pressures.Group A patients were more likely to have >3 recurrences (82.0% vs. 50.1%, p < .05).Conclusions: Patients with younger age of NCS onset and more syncopal recurrences manifest smaller LA and RA dimensions with distinct patterns of systolic and diastolic function and better LA reservoir and contraction properties. These findings may indicate an increased susceptibility to preload reduction, thereby triggering the NCS mechanism.

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

“…This results in a decrease in systemic blood pressure due to reduced venous return as in CAS 23. Consistent with our findings, previous studies have shown that lower LA volume was associated with the development of hypotension in patients with vasovagal syncope 5 6. Patients with LAVI ≥36 mL/m 2 did not experience fainting during a head-up tilt test 6.…”

“…Therefore, the cut-off value of 33.5 mL/m 2 for LAVI in the present study is considered reasonable. More aggressive hydration management has been reported to be preferable for these patients in vasovagal syncope 5. In addition, preoperative hydration was more common in the no-PH group than in the PH group in our study, and thus this intervention may be useful for preventing PH after CAS.…”

“…Second, the evaluation of right cardiac chamber function was inadequate in this study. A previous study showed that the function of the right cardiac chamber was also associated with the occurrence of vasovagal syncope 5. Third, carotid calcification was evaluated only using carotid ultrasound in the present study because CT and magnetic resonance angiography were only performed in 62.2% (n=132) and 90.5% (n=192) of the procedures, respectively.…”

“…Some studies have reported that low left atrial (LA) volumes, represented by the LA volume index (LAVI) on transthoracic echocardiography (TTE), are associated with the development of hypotension in vasovagal syncope. The intracardiac reserve volume estimated by the LA volume has been documented as an important factor in hemodynamic stability during acute preload reduction 5 6. However, no study has investigated the relationship between LAVI and hypotension after CAS.…”

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

“…In a recent study, Sotiriadou et al 23 . (2021) compared LA phasic function assessed by 2D STE in patients with VVS divided into two groups of more than 35 years old and less than 35 years old.…”