Department of Cardiology, Johns Hopkins University, Baltimore, Maryland; St. Marianna University School of Medicine, Kawasaki, Japan.
Department of Cardiology, Johns Hopkins University, Baltimore, Maryland.
JACC Cardiovasc Imaging. 2016 Oct;9(10):1164-1173. doi: 10.1016/j.jcmg.2016.01.038. Epub 2016 Sep 14.
The aim of this longitudinal study was to define the determinants of aging-related left ventricular (LV) remodeling and function in a large multiethnic population.
The influence of risk factor exposure on myocardial remodeling and function in humans across adult life remains incompletely understood. MESA (Multi-Ethnic Study of Atherosclerosis) is a longitudinal population-based cohort of asymptomatic adults at baseline.
We examined 757 participants who were free of clinical cardiovascular disease and underwent tagged cardiac magnetic resonance both at baseline and at the 10-year follow-up as part of the MESA study. LV remodeling, circumferential shortening (CS), and torsion were assessed by tagged cardiac magnetic resonance. Multivariable linear regression was used to determine the association of changes in risk factors with changes in cardiac geometry and function.
The mean age of participants was 63 ± 9 years at baseline; 50% were women. Overall, the LV mass-to-volume ratio increased by 10% over 10 years (p < 0.01). CS was unchanged (17.8% to 17.9%, p = 0.246), whereas torsion increased by 13% (3.8°/cm to 4.3°/cm, p < 0.001). Increased systolic blood pressure was associated with reduced CS (-0.02%/mm Hg, p < 0.01). Participants who remained on antihypertensive therapy during the whole study had a greater decrease in LV mass-to-volume ratio (-0.045 vs. no medication, p < 0.05) with a greater increase in CS (0.78% vs. no medication, p < 0.01). Moreover, greater LV mass at baseline was significantly associated with reduced CS (-0.02%/g, p < 0.01) and torsion (-0.02°/cm/g, p < 0.01) independently of risk factors.
Longitudinal observation demonstrates that LV mass and worsening risk factors are fundamental determinants of reduced regional myocardial shortening over 10 years. Increased torsion of the myocardial wall is seen with progressive concentric remodeling and may explain why systolic function is maintained with aging.
本纵向研究旨在确定在一个大型多民族人群中与年龄相关的左心室（LV）重构和功能的决定因素。
人们对成年后危险因素暴露对心肌重构和功能的影响仍了解甚少。MESA（动脉粥样硬化的多民族研究）是一个基于人群的无症状成年人的纵向队列研究，基线时纳入研究。
我们检查了 757 名参与者，他们在基线和 MESA 研究的 10 年随访期间均无临床心血管疾病，并接受了心脏磁共振标记检查。通过心脏磁共振标记评估 LV 重构、周向缩短（CS）和扭转。采用多变量线性回归来确定危险因素变化与心脏几何形状和功能变化之间的关系。
参与者的平均年龄为 63±9 岁，其中 50%为女性。总的来说，LV 质量/体积比在 10 年内增加了 10%（p<0.01）。CS 无变化（17.8%至 17.9%，p=0.246），而扭转增加了 13%（3.8°/cm 至 4.3°/cm，p<0.001）。收缩压升高与 CS 降低相关（-0.02%/mmHg，p<0.01）。在整个研究期间继续服用抗高血压药物的患者 LV 质量/体积比降低（-0.045 与无药物治疗相比，p<0.05），CS 增加（0.78%与无药物治疗相比，p<0.01）。此外，LV 质量的基线水平与 CS 降低（-0.02%/g，p<0.01）和扭转降低（-0.02°/cm/g，p<0.01）独立相关。
纵向观察表明，LV 质量和恶化的危险因素是 10 年内局部心肌缩短的主要决定因素。随着向心性重构的进展，心肌壁的扭转增加，这可能解释了为什么随着年龄的增长收缩功能得以维持。
