Large-scale genome-wide analysis identifies genetic variants associated with cardiac structure and function

AbstractEchocardiography is a widely used and clinically translatable imaging modality for the evaluation of cardiac structure and function in preclinical drug discovery and development. Echocardiograms are among the first in vivo diagnostic tools utilized to evaluate the heart due to its relatively low cost, high throughput acquisition, and non-invasive nature; however lengthy manual image analysis, intra- and inter-operator variability, and subjective image analysis presents a challenge for reproducible data generation in preclinical research. To combat the image-processing bottleneck and address both variability and reproducibly challenges, we developed a semi-automated analysis algorithm workflow to analyze long- and short-axis murine left ventricle (LV) ultrasound images. The long-axis B-mode algorithm executes a script protocol that is trained using a reference library of 322 manually segmented LV ultrasound images. The short-axis script was engineered to analyze M-mode ultrasound images in a semi-automated fashion using a pixel intensity evaluation approach, allowing analysts to place two seed-points to triangulate the local maxima of LV wall boundary annotations. Blinded operator evaluation of the semi-automated analysis tool was performed and compared to the current manual segmentation methodology for testing inter- and intra-operator reproducibility at baseline and after a pharmacologic challenge. Comparisons between manual and semi-automatic derivation of LV ejection fraction resulted in a relative difference of 1% for long-axis (B-mode) images and 2.7% for short-axis (M-mode) images. Our semi-automatic workflow approach reduces image analysis time and subjective bias, as well as decreases inter- and intra-operator variability, thereby enhancing throughput and improving data quality for pre-clinical in vivo studies that incorporate cardiac structure and function endpoints.

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The mitral regurgitation effects of cardiac structure and function in left ventricular noncompaction

Scientific Reports ◽

10.1038/s41598-021-84233-6 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Qing Zou ◽

Rong Xu ◽

Xiao Li ◽

Hua-yan Xu ◽

Zhi-gang Yang ◽

...

Keyword(s):

Mitral Regurgitation ◽

Nyha Class ◽

Left Ventricular ◽

Structure And Function ◽

Left Ventricular Geometry ◽

Cardiac Structure ◽

Left Ventricular Noncompaction ◽

Ventricular Noncompaction ◽

Cardiac Structure And Function ◽

And Function

AbstractThis study evaluated the effects of mitral regurgitation (MR) on cardiac structure and function in left ventricular noncompaction (LVNC) patients. The clinical and cardiovascular magnetic resonance (CMR) data for 182 patients with noncompaction or hypertrabeculation from three institutes were retrospectively included. We analyzed the difference in left ventricular geometry, cardiac function between LVNC patients with and without MR. The results showed that patients with MR had a worse New York Heart Association (NYHA) class and a higher incidence of arrhythmia (P < 0.05). MR occurred in 48.2% of LVNC patients. Compared to LVNC patients without MR, the two-dimensional sphericity index, maximum/minimum end-diastolic ratio and longitudinal shortening in LVNC patients with MR were lower (P < 0.05), and the peak longitudinal strain (PLS) of the global and segmental myocardium were obviously reduced (P < 0.05). No significant difference was found in strain in LVNC patients with different degree of MR; end diastolic volume, end systolic volume, and global PLS were statistically associated with MR and NYHA class (P < 0.05), but the non-compacted to compacted myocardium ratio had no significant correlation with them. In conclusion, the presence of MR is common in LVNC patients. LVNC patients with MR feature more severe morphological and functional changes. Hypertrabeculation is not an important factor affecting structure and function at the heart failure stage.

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Differences between diabetic and non-diabetic nephropathy patients in cardiac structure and function at the beginning of hemodialysis and their impact on the prediction of mortality

Journal of International Medical Research ◽

10.1177/0300060521997588 ◽

2021 ◽

Vol 49 (3) ◽

pp. 030006052199758

Author(s):

Chao Tang ◽

Han Ouyang ◽

Jian Huang ◽

Jing Zhu ◽

Xiaosong Gu

Keyword(s):

Diabetic Nephropathy ◽

Diastolic Dysfunction ◽

Peak Velocity ◽

Structure And Function ◽

Cardiac Valve ◽

Cardiac Structure ◽

Prediction Of Mortality ◽

Cardiac Structure And Function ◽

Lv Diastolic Dysfunction ◽

And Function

Objectives To characterize differences in cardiac structure and function in hemodialysis (HD) patients with diabetic nephropathy (DN) and in those without using echocardiography and to determine their impact on the prediction of mortality using echocardiographic parameters. Methods Clinical, laboratory, and echocardiographic data were collected from patients commencing HD. Results Compared with those without DN, patients with DN had lower peak velocity of the early diastolic wave (e′), larger left atria, and higher peak early diastolic velocity (E)/e′ and peak velocity of tricuspid regurgitation (TR). In addition, a larger proportion of DN patients had a combination of left ventricular (LV) diastolic dysfunction, cardiac valve calcification, moderate-to-severe cardiac valve regurgitation (CVR), and at least moderate pericardial effusion (PE). After accounting for age, sex, smoking, hypertension, hemoglobin, and albumin, DN was responsible for e′ < 10 cm/s, E/e′ >13 m/s, TR >2.8 m/s, LV diastolic dysfunction, CVR, and PE. LV diastolic dysfunction and E/e′ >13 were the most useful predictors of mortality in patients with DN. Conclusions Patients with DN who undergo HD tend to have worse LV diastolic function and are more likely to have heart valve problems. LV diastolic dysfunction and E/e′ are predictors of death in DN patients.

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