MacIver David H, Zhang Henggui
Biological Physics Group, Department of Astronomy and Physics, University of Manchester, Manchester, United Kingdom; Department of Cardiology, Taunton & Somerset Hospital, United Kingdom.
Biological Physics Group, Department of Astronomy and Physics, University of Manchester, Manchester, United Kingdom.
Int J Cardiol. 2024 Aug 1;408:132139. doi: 10.1016/j.ijcard.2024.132139. Epub 2024 May 3.
This study compared commonly used methods for calculating left ventricular wall stress with the finite element analysis and evaluated different approaches to strain estimation. We sought to improve the accuracy of contractance estimation by developing a novel stress equation.
Multiple methods for calculating LV contractile stress and strain exist. Contractance is derived from stress and strain information and is a measure of myocardial work per unit volume of muscle. Precise stress and strain information are essential for its accurate evaluation.
We compared widely used methods for stress and strain calculations across diverse clinical scenarios representing distinct types of left ventricular myocardial disease. Our analysis revealed significant discrepancies in both the stress and strain values obtained with different methods. However, a newly developed modified version of the Mirsky equation demonstrated close agreement with the finite element analysis results for circumferential stress, while the Lamé method produced results close to those of finite element analysis for longitudinal stress and improved contractance accuracy.
This study highlights significant inconsistencies in stress and strain values calculated using different methods, emphasising the potential impact on contractance calculations and subsequent clinical interpretation. We recommend adopting the Lamé method for longitudinal stress assessment and the modified Mirsky equation for circumferential stress analysis. These methods offer a balance between accuracy and feasibility, making them advantageous for clinical practice. By adopting these recommendations, we can improve the accuracy of LV wall stress and strain estimates, leading to more dependable contractance calculations, better prognostication and improved clinical decisions.
Accurately estimating myocardial stress and strain is of paramount significance in clinical practice because the calculation of the contractance, defined and quantified by myocardial active strain energy density, necessitates correct stress and strain data. Contractance, which assesses myocardial work per unit muscle volume, has emerged as a promising indicator of contractile function and a predictor of future risk. The new recommendations for calculating myocardial stress improve the reliability of calculating contractance and enhance the understanding of myocardial diseases.
本研究将计算左心室壁应力的常用方法与有限元分析进行比较，并评估不同的应变估计方法。我们试图通过开发一种新的应力方程来提高收缩能力估计的准确性。
存在多种计算左心室收缩应力和应变的方法。收缩能力源自应力和应变信息，是每单位肌肉体积心肌做功的一种度量。精确的应力和应变信息对于其准确评估至关重要。
我们在代表不同类型左心室心肌疾病的多种临床场景中比较了广泛使用的应力和应变计算方法。我们的分析揭示了不同方法获得的应力和应变值存在显著差异。然而，新开发的米尔斯基方程的修改版本在周向应力方面与有限元分析结果显示出密切一致性，而拉梅方法在纵向应力方面产生的结果接近有限元分析结果，并提高了收缩能力的准确性。
本研究突出了使用不同方法计算的应力和应变值存在显著不一致性，强调了对收缩能力计算及后续临床解释的潜在影响。我们建议采用拉梅方法进行纵向应力评估，采用修改后的米尔斯基方程进行周向应力分析。这些方法在准确性和可行性之间取得了平衡，使其在临床实践中具有优势。通过采纳这些建议，我们可以提高左心室壁应力和应变估计的准确性，从而进行更可靠的收缩能力计算、更好的预后评估以及改进临床决策。
在临床实践中准确估计心肌应力和应变至关重要，因为由心肌主动应变能量密度定义和量化的收缩能力的计算需要正确的应力和应变数据。收缩能力评估每单位肌肉体积的心肌做功，已成为收缩功能的一个有前景的指标和未来风险的预测因子。计算心肌应力的新建议提高了收缩能力计算的可靠性，并增进了对心肌疾病的理解。
