Quantitative analysis of left ventricular dyssynchrony using cardiac computed tomography versus three-dimensional...

Area of Science:

• Cardiology
• Medical Imaging
• Diagnostic Techniques

Background:

• Assessing left ventricular (LV) dyssynchrony is crucial for patients considered for cardiac resynchronisation therapy (CRT).
• Real-time three-dimensional echocardiography (RT3DE) is a current method for this assessment.
• Limitations of RT3DE include analysis time and reproducibility.

Purpose of the Study:

• To investigate the feasibility of cardiac computed tomography (CCT) in determining intraventricular dyssynchrony.
• To compare CCT with RT3DE for dyssynchrony assessment in CRT candidates.
• To evaluate the reproducibility and analysis time of CCT versus RT3DE.

Main Methods:

• 35 patients considered for CRT underwent both RT3DE and ECG-gated contrast-enhanced 64-slice dual-source CCT.
• Left ventricular (LV) dyssynchrony was quantified using the standard deviation index (SDI) with the 4D LV-Analysis software for both techniques.
• Comparison focused on correlation of SDI, end-systolic volume, end-diastolic volume, and LV ejection fraction.

Main Results:

• High correlations were found between CCT and RT3DE for volumetric parameters (r=0.92-0.95) and global dyssynchrony index SDI (r=0.84).
• Correlation for SDI improved to r=0.90 after excluding segments with poor echocardiographic image quality.
• CCT analysis time was significantly shorter (162s vs. 608s) and reproducibility was significantly higher (4.5% vs. 7.9% interobserver variability) compared to RT3DE.

Conclusions:

• Quantitative assessment of LV dyssynchrony is feasible using CCT.
• CCT demonstrates higher reproducibility and significantly faster analysis times than RT3DE.
• CCT presents a valuable alternative for dyssynchrony assessment in patients considered for CRT.