Predictive value of total atrial conduction time for developing cerebrovascular stroke in patients with sinus rhythm and normal left ventricular systolic function, a case-control study
Authors: Ghanem I , Dwedar A , Marwad A , Gouda M 
Published: October 2024

Abstract

Background
Stroke is the second leading cause of death worldwide. Recently, atrial cardiopathy has become recognized as a substantial risk factor for cerebrovascular stroke. Greater LA size is linked to stroke in AF patients, but few data linking LA size to stroke in population with sinus rhythm.

Purpose
To investigate the value of total atrial conduction time (TACT) measured non-invasively by assessing PA-TDI duration as a predictor of stroke in patients who initially presented with sinus rhythm and have normal LV systolic function.

Methods
In our case-control study, we included 156 patients with acute ischemic stroke and 50 control subjects all presented in sinus rhythm and normal LV systolic function. All participants underwent echocardiography. The bi-plane modified Simpson's approach was used to determine the LV-EF. The left atrial (LA) diameter was measured also left atrial volume index (LAVI) was assessed. The PA-TDI interval was used to estimate the TACT. In the apical four-chamber view, the pulsed-wave tissue Doppler sample was positioned on the lateral and septal walls of the LA above the mitral annulus. The time between the onset of the P wave (lead II) and the peak of the A' wave was called the PA-TDI interval. Also, speckle tracking indices of LA strain were measured.

Results
LA volume index was larger in the stroke group (39.24±4 versus 33.6±2.8, p: 0.01), PA-TDI duration showed statistical highly significant difference between both groups (165.94±21.695 versus 99.4±22.960, p: &lt;0.001). There were significantly impaired LAS parameters in the stroke group (LA reservoir, contraction & conduit strain, 22.7%, -6.6% & -16.1% versus 40%, -12%, and − 27% in the control group with P &lt; 0.000). ROC curve showed the best cutoff point for LA volume index is &gt;42.2 ml/m2 for prediction of stroke with area under the curve (AUC): 0.7, p value is 0.005. ROC curve showed the best cutoff point for PA-TDI is &gt;155.5 ms. with AUC: 0.9, 90% sensitivity, 91% specificity, p value: &lt;0.001. ROC curve showed that LA reservoir strain and LA stiffness can independently predict stroke at cut-off values of 30% & 24.5% respectively, P &lt; 0.001. Multivariate logistic regression analysis showed that hypertension, LA volume index, LA stiffness and PA-TDI duration are independent predictors of stroke (p: &lt; 0.05, &lt; 0.05, &lt; 0.01 and &lt; 0.001 respectively).

Conclusions
The assessment of electromechanical asynchrony by measuring the PA-TDI duration may help to predict patients at risk for stroke. It is easy to measure without the need for special software like speckle tracking indices. We also advise patients who exceed the cutoff points of LA volume index and PA-TDI duration to receive antithrombotic therapy for better stroke prevention. Also we recommend adding PA-TDI to CHA2DS2-VASC-HSF score to assess stroke risk in patients with sinus rhythm and paroxysmal AF during their sinus rhythm intervals.