Lower Free Wall Research Articles

3D echocardiographic evaluation of right ventricular function and strain: a prognostic study in paediatric pulmonary hypertension.

To evaluate right ventricular functional indices using 3D echocardiography (3DE) between normal children and paediatric pulmonary hypertension (PH) patients, and to evaluate these indices as outcome predictors in children with PH. Ninety-six paediatric PH patients from 2014 to 2016 were compared with 40 normal controls. All patients underwent 3DE and off-line analysis generated 3D end-diastolic volume, 3D end-systolic volume, 3D stroke volume, 3D right ventricular (RV) ejection fraction (EF), RV longitudinal strain (LS) free wall and septum, tricuspid annular plane systolic excursion (TAPSE), and fractional area change (FAC). PH patients had higher RV volumes, lower RV EF, lower free wall and septal RVLS, lower TAPSE, and lower FAC compared with normal controls (all P < 0.001). 3D RV EF, free wall RVLS, and FAC are predictors of adverse clinical outcomes [hazard ratio (confidence interval) 0.1 (0.03-0.27], P < 0.001; 0.17 (0.07-0.45), P < 0.001; 0.08 (0.03-0.22); P < 0.001, respectively). Paediatric PH patients have impaired RV function compared with normal children. 3D RV EF, volumes, FAC, and free wall RV strain serve as outcome predictors for paediatric PH patients.

Role of surface electrocardiogram precordial leads in localizing different anatomic sites of ectopic atrial tachycardia arising from lower right atrium in pediatric population.

The study was designed to examine P wave morphology (PWM) in precordial leads (V1 -V6 ) during ectopic atrial tachycardia (EAT) originating from low right atrium (RA) to identify the anatomic sites of these foci in children. Twenty-three consecutive pediatric patients (56% females, mean age 8.5±2.5) with EAT originating from the low RA underwent detailed atrial endocardial activation mapping and radiofrequency ablation. PWM during EAT was analyzed using standard 12-lead ECG in relation to successful ablation sites in RA. Ectopic atrial tachycardia originated from coronary sinus ostium (CSo) in 12 patients, nonseptal tricuspid annulus (TA) in five, lower crista terminalis (CT) in three and lower free wall in three. In lead V1 , PWM showed a positive pattern during EAT originating from CSo (8/12) [91.7% sensitivity, 100% specificity, 100% positive predictive value (PPV), 100% negative predictive value (NPV)]. A negative pattern was observed in EAT originating from lower free wall (1/3) and nonseptal TA (5/5) [50% sensitivity, 100% specificity, 100% PPV, 75% NPV], while isoelectric pattern was in EAT originating from lower CT (3/3) [100% sensitivity, 100% specificity, 100% PPV, 100% NPV]. In leads V3 -V6 , PWM showed a negative pattern in at least two consecutive leads during EAT from CSo (12/12), nonseptal TA (5/5) and lower free wall (3/3) while it was positive in EAT originating from lower CT (3/3) [100% sensitivity, 95% specificity, 75% PPV and 100% NPV]. P wave morphology in precordial leads can help differentiate the anatomic sites of EAT from lower RA with high PPVs and NPVs.

Diagnosis of atrial tachycardias originating from the lower right atrium: importance of P-wave morphology in the precordial leads V3–V6

This study aimed to characterize P-wave morphology (PWM) in leads V3-V6 during focal atrial tachycardia (AT) originating from the lower right atrium (RA), and to investigate the role of interatrial conduction (IAC) pathways in the formation of PWM. Twenty-eight consecutive patients with tachycardia foci in the lower RA underwent detailed atrial endocardial activation mapping and radiofrequency catheter ablation. P-wave configuration was analysed using standard 12-lead electrocardiogram. Atrial tachycardia originated from lower non-septal tricuspid annulus (LTA) (n = 11), coronary sinus ostium (CSo) (n = 11), lower crista terminalis (LCT) (n = 4), or lower free wall (n = 2). In leads V3-V6, PWM showed a negative pattern in at least two consecutive leads during AT originating from CSo (11/11) and LTA (9/11), with an associated sensitivity of 91%, specificity of 100%, positive predictive value (PPV) of 100%, and negative predictive value (NPV) of 75%. A positive PWM was observed in three of four ATs originating from LCT, with an associated sensitivity of 75%, specificity of 100%, PPV of 60%, and NPV of 96%. A negative PWM in V3-V6 was consistent with a preferential IAC through musculature in the vicinity of the CS and an activation of both atria in an antero-posterior direction. In contrast, a positive PWM was associated with the engagement of a posterior (non-CS-related) interatrial connection. Characteristic PWMs in V3-V6 may accurately differentiate the anatomic sites of AT from the low RA with high PPVs and NPVs. P-wave morphology in V3-V6 is likely to be influenced by the engagement of the preferential IAC.