Electrocardiographic Z-axis QRS-T voltage-time-integral in patients with typical right bundle branch block - Correlation with echocardiographic right ventricular size and function.

Background: Right bundle branch block (RBBB) can be benign or associated with right ventricular (RV) functional and structural abnormalities. Our aim was to evaluate QRS-T voltage-time-integral (VTI) compared to QRS duration and lead V1 R' as markers for RV abnormalities.

Methods: We included adults with an ECG demonstrating RBBB and echocardiogram obtained within 3 months of each other, between 2010 and 2020.

Electrocardiographic prediction of left ventricular hypertrophy in women and men with left bundle branch block - Comparison of QRS duration, amplitude and voltage-time-integral.

Background: Standard ECG criteria for left ventricular (LV) hypertrophy rely on QRS amplitudes. However, in the setting of left bundle branch block (LBBB), ECG correlates of LV hypertrophy are not well established. We sought to evaluate quantitative ECG predictors of LV hypertrophy in the presence of LBBB.

Reduction of left ventricular outflow tract obstruction with transcatheter mitral valve repair.

Many patients with severe mitral regurgitation cannot undergo conventional mitral valve surgery due to prohibitive surgical risk and are candidates for transcatheter repair with an edge-to-edge technique. Prior reports suggest efficacy with this approach for mitral regurgitation due to hypertrophic cardiomyopathy with left ventricular outflow obstruction. We present a case report of transcatheter mitral valve repair for posterior leaflet prolapse with concomitant left ventricular outflow tract obstruction due to systolic anterior motion of the mitral valve in the absence of hypertrophic cardiomyopathy.

Quantification of the variability associated with repeat measurements of left ventricular two-dimensional global longitudinal strain in a real-world setting.

Background: Global longitudinal strain (GLS) derived from two-dimensional speckle-tracking is an emerging technology, but lack of industry standards limits its application. Prior studies support using this tool to identify subclinical disease through serial changes, but the variability introduced by a change in vendor or reader is not well defined.

Methods: Fifty study subjects were prospectively identified to include four subgroups to ensure a broad range of GLS: normal (n = 20), left ventricular hypertrophy (n = 10), ST-segment elevation myocardial infarction (n = 10), and systolic heart failure (n = 10).

Two-dimensional longitudinal strain in patients with aortic stenosis can be reliably acquired at the bedside without additional benefit of offline analysis.

Background: Two-dimensional strain echocardiography (2DS) has been used to assess ventricular function in several disease states. In previous studies of 2DS, strain analysis was usually performed offline by experienced echocardiographers. The applicability of 2DS in busy clinical labs would be enhanced if 2DS could be reproducibly measured by sonographers at the time of the echo exam.

Integrated backscatter during harmonic and fundamental frequency imaging--effect of depth, mechanical index, and tissue anisotropy: implications for myocardial tissue characterization.

Objective: To explore the potential advantages of tissue harmonic imaging (THI) versus fundamental frequency imaging (FFI) when applied to tissue characterization.

Methods: A Philips Medical Systems Sonos 5500 echocardiograph equipped with a broadband transducer (S4) and an on-line quantitative analysis software package (Acoustic Densitometry) was used for imaging. The effect of mechanical index (MI), imaging depth, and anisotropy on relative backscatter amplitude was evaluated.