Relationship of left atrial mechanics to electrical activity on surface electrocardiography in idiopathic dilated cardiomyopathy

Abstract

Aim: (1) Assess left atrial (LA) mechanics and electromechanical delay in patients with idiopathic dilated cardiomyopathy (IDCM), and (2) examine the relationship between atrial electromechanical delay and atrial electrical activity [P-wave duration, P-wave dispersion (PWD) and P terminal force (PTF)] on surface ECG.Methods: 73 IDCM patients (age 36 ± 17 years); 63% men, 25 age & sex matched healthy subjects were studied. LA atrial electromechanical delay & mechanics (εsys, SRsys, SRe, SRa) were measured with 2D-strain. From 12-lead electrocardiograms, P-wave duration, PWD and PTF calculated.Results: Reservoir, conduit and contractile functions were predominantly reduced compared to control (P < 0:001). Intra-atrial electromechanical delay was 88.9 ± 84.6 in IDCM versus 27.4 ± 16.5 in control (P < 0:0001). In IDCM, PWD (52.89 ± 15), Pmax(98 ± 17.5) and PTF(58.2 ± 36) were significantly increased compared to control (36.20 ± 8.9, 79 ± 9.9, 25.22 ± 8.76) respectively (P < 0:0001). A positive correlation was detected between intraatrial electromechanical delay and PWD &PTF (r D 0:5, P < 0:0001). By stepwise multiple linear regression analyses, LA reservoir function (LA εsys) [β = 0:754; CI at 95%:0.3560.780, P <0:001] and LA volume [β = 0:743; CI 95%:0.4230.75, P < 0:001], and PWD [β = 0.848; CI 95%:0.311 0.644, P < 0:0001], and PTF [β = 0:927; CI 95%: 0.3570.722, P < 0:0001] are independent predictors for LA electromechanical delay in IDCM.Conclusion: In addition to altered LA mechanics, atrial electromechanical delay gets longer in IDCM and is correlated with PWD and PTF. Atrial electrical dispersion on surface ECG could be early index of LA dysfunction that deserves further study.

Atrial conduction explains the occurrence of the P‐wave dispersion phenomenon, but weakly

“…The mean values of PWD and Pmax are increased in our series with respect to the reported upper cutoff points for these parameters. Analyzing 295 patients randomly selected from the original cohort of the Framingham study with a wide age range and without cardiovascular disease or hypertension, diabetes mellitus or obesity, Magnani et al 6 determined that the median PWD was 34 ms with a range between the 25‐75 percentile of 28‐43 ms. Pérez‐Riera et al 3 consider that the normal value is between 20 and 38 ms with a mean of 29 ms, almost equal to that reported in the control group used by Dilaveris et al 1 that presented a range of 21‐35 ms (mean: 28 ms). The P wave is prolonged when its duration is >120 ms 7 .…”

“…The local theory is the most widely disseminated theory. It argues that atrial zones with different conduction velocities give rise to P waves of different durations throughout the 12 leads of the electrocardiogram 3 . Most connoisseurs of this topic accept that PWD reflects prolonged, inhomogeneous, and anisotropic distribution of connections between myocardial fibers resulting in discontinuous anisotropic propagation of sinus impulses, as well as, inhomogeneous and discontinuous atrial conduction 4 .…”

Relation of atrial electromechanical delay to P‐wave dispersion on surface ECG using vector velocity imaging in patients with hypertrophic cardiomyopathy

“…To achieve greater precision in measuring P‐wave dispersion, we measured simultaneous digital recording of all 12 ECG leads and on computer screen with the high zoom capabilities, Figure 1. P‐wave dispersion is defined as the difference between maximum and minimum P‐wave durations measured at all ECG derived leads (Acar et al., 2009; Badran et al., 2019; Liu et al., 1998; Magnani et al., 2010; Pala et al., 2010; Rein et al., 2003; Sanders et al., 2003; Tosun et al., 2018). Intraobserver and interobserver coefficients of variation were found to be 4.1% and 4.4% for PWD, respectively (Badran et al., 2019; Pala et al., 2010; Tosun et al., 2018…”

“…Recently, strain and strain rate measured by novel vector velocity imaging (VVI) have been used in evaluating cardiac mechanics. It allows simultaneous and precise analysis of atrial mechanics during its different phases reservoir, conduit, and contractile functions (Badran et al, 2019; Pala et al., 2010; Sanders et al., 2003) in addition to measurement of atrial electromechanical delay (Acar et al., 2009; Rein et al, 2003).…”

Interatrial Electromechanical Conduction Delay by ECG P-Wave and Echocardiographic Tissue Doppler Imaging for Diabetics Attending Merjan Teaching Hospital, A Comparison Study

“…The duration time between atrial mechanical peak contraction and the electrical depolarization of Corresponding Author: Oday J. Al-Salihi Dr. Prof., College of Medicine, University of Babylon/ Iraq e-mail: dr.oday78@yahoo.com the atrium is called atrial electromechanical delays (AEMDs). AEMDs prolongation might be considered as a sign to distinguish arrhythmia (PAF) in patients than in control and prediction of PAF occurrence in observational and case-control studies as Badran and his associates found (1) . The clinical suggestion supports the opinion that atrial electromechanical conduction delay prolongation suggest left atrial remodeling electricity, that is fundamental for the AF maintenance (2) .…”