Atrial Electromechanical Delay Measured by Tissue Doppler Imaging in Patients with Secundum Atrial Septal Defects

The Author's Contributions to Echocardiography Literature (Part II-1991-2020)

The author's contribution up to 1990 was reviewed in part I and the echo contributions from 1991 to 2020 will be reviewed in part II. These include defining the relationship between the quantity of shunt across the atrial septal defect (ASD) and the diameter of ASD by echo and angio on the one side and the stretched diameter of the ASD on the other; echocardiographic assessment of balloon-stretched diameter of secundum ASDs; development of echocardiographic predictors of accomplishment of percutaneous closure of ASDs with the buttoned device, highlighting limitations of echocardiography in comprehensive assessment of mixed type of total anomalous pulmonary venous connection; description of follow-up echocardiographic results of transcatheter closure of ASD with buttoned device; review of ultrasound studies; depiction of collaborative echocardiographic and Doppler studies; echocardiographic appraisal of the outcome of balloon pulmonary valvuloplasty; editorials; ventricular septal aneurysm causing pulmonary outflow tract obstruction in the morphologic left ventricle in corrected transposition of the great arteries; dependability of echocardiographic assessment of angiographic minimal diameter of the ductus; occurrence of supravalvular pulmonary artery stenosis after a Nuss procedure; echocardiographic assessment of neonates who were suspected of having heart disease; role of echocardiographic studies in the appraisal of patent ductus arteriosus in the premature babies; and the role of pressure recovery in explaining differences between simultaneously measured Doppler and cardiac catheterization pressure gradients across outflow tract stenotic lesions.

Evaluating the effect of nasal septoplasty on atrial electromechanical features

BACKGROUND

Recent studies have demonstrated that right ventricular (RV) dysfunction and increased pulmonary artery pressure may be frequent in patients with upper airway obstruction. In this study, we evaluated atrial conduction delays in patients with upper airway obstruction secondary to nasal septum deviation (NSD).

METHODS

A total of 32 patients with upper airway obstruction secondary to NSD undergoing a septoplasty procedure were enrolled in this study. Preoperative electrocardiography and transthoracic echocardiography were performed in all patients who underwent surgery. The mean pulmonary artery pressure (mPAP) and atrial conduction time (ACT) were recorded before and 6 months after the surgical procedures.

RESULTS

The PAP was significantly lower postoperatively than preoperatively (20.75 ± 4.83 vs. 24.68 ± 5.26; P < 0.001). The postoperative Electromechanical Delay of Mitral septal wall (EMD-MS) value was significantly lower than that preoperatively (46.20 ± 8.5 vs. 40.5 ± 9.9; P < 0.001). The postoperative Electromechanical Delay of Mitral lateral wall (EMD-ML) value decreased significantly compared to the preoperative period (46.3 ± 7.4 vs. 40.6 ± 9.3; P < 0.001). The postoperative Electromechanical Delay of Tricuspit lateral wall (EMD-TL) value was significantly lower than that preoperatively (43.8 ± 7.0 vs. 38.1 ± 9.1; P < 0.001). There was no significant change in pre- or postoperative measurements of inter- and intra-atrial conduction delays.

CONCLUSIONS

We demonstrated that upper airway obstruction secondary to NSD causes a significant increase in mPAP and a significant delay in ACT, which improved after nasal septoplasty. According to these results, we conclude that upper airway obstruction may be an important risk factor for pulmonary arterial hypertension, RV dysfunction, and atrial arrhythmias, especially in unoperated cases.

The role of the atrial electromechanical delay in predicting atrial fibrillation in beta-thalassemia major patients

BACKGROUND

Paroxysmal atrial tachyarrhythmias frequently occur in beta-thalassemia major (β-TM) patients. The aim of the current study was to evaluate the atrial electromechanical delay (AEMD) in a large β-TM population with normal cardiac function and its relationship to atrial fibrillation (AF) onset.

METHODS

Eighty β-TM patients (44 men, 36 women), with a mean age of 36.2 ± 11.1 years, and 80 healthy subjects used as controls, matched for age and gender, were studied for the occurrence of AF during a 5-year follow-up, through 30-day external loop recorder (ELR) monitoring performed every 6 months. Intra-AEMD and inter-AEMD of both atria were measured through tissue Doppler echocardiography. P-wave dispersion (PD) was carefully measured using 12-lead electrocardiogram (ECG).

RESULTS

Compared to the healthy control group, the β-TM patients showed a statistically significant increase in inter-AEMD, intra-left AEMD, maximum P-wave duration, and PD. Dividing the β-TM group into two subgroups (patients with or without AF), the inter-AEMD, intra-left AEMD, maximum P-wave duration, and PD were significantly higher in the subgroup with AF compared to the subgroup without AF. There were significant good correlations of intra-left AEMD and inter-AEMD with PD. A cut-off value of 40.1 ms for intra-left AEMD had a sensitivity of 76.2% and a specificity of 97.5% in identifying β-TM patients with AF risk. A cut-off value of 44.8 ms for inter-AEMD had a sensitivity of 81.2% and a specificity of 98.7% in identifying this category of patients.

CONCLUSIONS

Our results showed that the echocardiographic atrial electromechanical delay indices (intra-left and inter-AEMD) and the PD were significantly increased in β-TM subjects with normal cardiac function. PD and AEMD represent non-invasive, inexpensive, useful, and simple parameters to assess the AF risk in β-TM patients.

Impact of Continuous Positive Airway Pressure Therapy on Atrial Electromechanical Delay in Obesity-Hypoventilation Syndrome Patients

BACKGROUND

Obesity-hypoventilation syndrome (OHS) is defined as daytime hypercapnia and hypoxemia in obese patients with sleep-disordered breathing. We evaluated the electrocardiographic P-wave duration and dispersion (PD) and echocardiographic noninvasive indicators of atrial conduction heterogeneity in OHS patients and the impact of CPAP on atrial conduction and atrial fibrillation incidence.

METHODS AND RESULTS

We enrolled 50 OHS patients and 50 sex- and age-matched obese subjects as control. Study population underwent cardiologic evaluation and polysomnography before enrollment, at 1- and 6-month follow-ups after CPAP therapy. The OHS group showed a significant increase in inter-atrial (35.2 ± 8 milliseconds vs. 20.1 ± 2.7 milliseconds, P < 0.0001), intra-left (30.5 ± 7.2 milliseconds vs. 16.5 ± 2 milliseconds, P < 0.0001), and intra-right atrial electromechanical delays (AEMD)(24.8 ± 10 milliseconds vs. 15 ± 2.6 milliseconds, P < 0.0001) as well as in Pmax (130 ± 7.4 milliseconds vs. 97 ± 7.2 milliseconds, P = 0.002) and PD (56.5 ± 8.5 milliseconds vs. 31 ± 7.2 milliseconds, P = 0.002) compared to the control group. Significant improvement was noted after 6 months of CPAP therapy in inter-atrial (35.2 ± 8 milliseconds vs. 24.5 ± 6.3 milliseconds, P < 0.0001), intra-left (30.5 ± 7.2 milliseconds vs. 20.6 ± 5 milliseconds, P = 0.003), and intra-right AEMD (24.8 ± 10 milliseconds vs. 17 ± 7.5 milliseconds, P < 0.0001), as well as in Pmax (130 ± 7.4 milliseconds vs. 95 ± 10 milliseconds, P < 0.0001) and in PD (56.5 ± 8.5 milliseconds vs. 32.5 ± 6 milliseconds, P < 0.0001) in the OHS group. External loop recorder monitoring detected paroxysmal AF in 19 OHS patients (38%) with significant reduction in paroxysmal AF episodes (12 ± 6 vs. 47 ± 12, P < 0.0001) after 6-month CPAP therapy.

CONCLUSION

Our findings showed a significant increase of electrocardiographic and echocardiographic indexes of atrial conduction heterogeneity in OHS patients. The CPAP therapy, having a positive impact on atrial conduction time, seems to reduce AF incidence in OHS patients.

Atrial Septal Aneurysms and Supraventricular Arrhythmias: The Role of Atrial Electromechanical Delay

BACKGROUND

Paroxysmal supraventricular arrhythmias (SVAs) frequently occur in patients with atrial septal aneurysm (ASA). The aim of the current study was to evaluate the electrocardiographic (P-wave duration and dispersion) and echocardiographic (atrial electromechanical delay, AEMD) noninvasive indicators of atrial conduction heterogeneity in healthy ASA subjects without interatrial shunt and to assess the AEMD role in predicting the SVAs onset in this population.

MATERIALS AND METHODS

One hundered ASA patients (41 males, mean age of 32.5 ± 8 years) and 100 healthy subjects used as controls, matched for age and gender, were studied for the occurrence of SVAs during a 4-year follow-up, through 30-day external loop recorder (ELR) monitoring performed every 3 months. ASAs were diagnosed by transthoracic echocardiography based on the criteria of a minimal aneurismal base of ≥15 mm and an excursion of ≥10 mm. Intra-AEMD and inter-AEMD of both atria were measured through tissue Doppler echocardiography. P-wave dispersion (PD) was carefully measured using 12-lead electrocardiogram (ECG).

RESULTS

Compared to the healthy control group, the ASA group showed a statistically significant increase in inter-AEMD, intra-left AEMD, maximum P-wave duration, and PD. Dividing the ASA group into 2 subgroups (patients with or without SVAs), the inter-AEMD, intra-left AEMD, P max, and PD were significantly higher in the subgroup with SVAs compared to the subgroup without SVAs. There were significant good correlations of intra-left AEMD and inter-AEMD with PD. A cutoff value of 40.1 msec for intra-left AEMD had a sensitivity of 82% and a specificity of 83% in identifying ASA patients at risk for SVA.

CONCLUSION

Our results showed that the echocardiographic AEMD indices (intra-left and inter-AEMD) and the PD were significantly increased in healthy ASA subjects without interatrial shunt. PD and AEMD represent noninvasive, inexpensive, useful, and simple parameters to assess the SVAs' risk in ASA patients.

Evaluation of cardiac functions and atrial electromechanical delay in children with adenotonsillar hypertrophy

Deterioration of the right ventricular (RV) functions and the increase in the pulmonary arterial pressure (PAP) of children with moderate to severe adenotonsillar hypertrophy (ATH) have been well described. In addition to these complications, this study aimed to investigate the influence of ATH on the conduction system. The study investigated 46 patients with a diagnosis of ATH and 46 healthy control subjects. Conventional echocardiography, P-wave dispersion (Pd), tissue Doppler imaging (TDI) findings, and atrial electromechanical delay (AED) were compared between the patients and the control subjects before and after adenotonsillectomy. The maximum P-wave duration and Pd were significantly higher in the patients than in the control subjects (p < 0.001). The patient group showed significantly greater RV end-diastolic dimension (p = 0.01), right atrial area (p < 0.001), and mean PAP (p = 0.03) but lower E/A ratios for the mitral (p = 0.04) and tricuspid (p = 0.01) valves and a shorter pulmonary flow trace acceleration time (p = 0.03). The tricuspid annular-plane systolic excursion was similar between these groups (p = 0.21). In the patient group, TDI studies showed significantly lower E'/A' ratios for the tricuspid lateral (p = 0.006) and mitral septal (p = 0.003) segments than in the control group. The myocardial performance index was lower for the mitral lateral, mitral septal, and tricuspid lateral segments in patient group (p < 0.001). Similarly, AED was prolonged in the patient group at all three segments (p < 0.001). Also, the patient group showed a significantly longer interatrial (p = 0.03) and intraatrial (p = 0.04) electromechanical delay. However, all the electro- and echocardiographic parameters were similar between the patients and the control subjects after adenotonsillectomy (p > 0.05). The prolongations in P-wave duration, Pd, and inter- and intraatrial electromechanical delays were first shown in this population. The cardiac changes induced by ATH-associated hypoxia may facilitate arrhythmias during the long term.