BACKGROUND: Very severe chronic obstructive pulmonary disease causes cor pulmonale with elevated pulmonary vascular resistance and secondary reductions in left ventricular filling, stroke volume, and cardiac output. We hypothesized that emphysema, as detected on computed tomography (CT), and airflow obstruction are inversely related to left ventricular end-diastolic volume, stroke volume, and cardiac output among persons without very severe lung disease. METHODS: We measured left ventricular structure and function with the use of magnetic resonance imaging in 2816 persons who were 45 to 84 years of age. The extent of emphysema (expressed as percent emphysema) was defined as the percentage of voxels below -910 Hounsfield units in the lung windows on cardiac computed tomographic scans. Spirometry was performed according to American Thoracic Society guidelines. Generalized additive models were used to test for threshold effects. RESULTS: Of the study participants, 13% were current smokers, 38% were former smokers, and 49% had never smoked. A 10-point increase in percent emphysema was linearly related to reductions in left ventricular end-diastolic volume (-4.1 ml; 95% confidence interval [CI], -3.3 to -4.9; P<0.001), stroke volume (-2.7 ml; 95% CI, -2.2 to -3.3; P<0.001), and cardiac output (-0.19 liters per minute; 95% CI, -0.14 to -0.23; P<0.001). These associations were of greater magnitude among current smokers than among former smokers and those who had never smoked. The extent of airflow obstruction was similarly associated with left ventricular structure and function, and smoking status had similar modifying effects on these associations. Percent emphysema and airflow obstruction were not associated with the left ventricular ejection fraction. CONCLUSIONS: In a population-based study, a greater extent of emphysema on CT scanning and more severe airflow obstruction were linearly related to impaired left ventricular filling, reduced stroke volume, and lower cardiac output without changes in the ejection fraction.
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机译：背景：非常严重的慢性阻塞性肺疾病会导致肺心病，并伴有肺血管阻力升高，继而减少左心室充盈，中风量和心输出量。我们假设计算机断层扫描（CT）所检测到的肺气肿和气流阻塞与没有严重肺病的人的左心室舒张末期容积，中风量和心输出量成反比。方法：我们使用磁共振成像技术对28至45岁的2816人进行了左心室结构和功能的测量。肺气肿的程度（表示为肺气肿百分比）定义为在心脏计算机断层扫描中肺窗中低于-910 Hounsfield单位的体素百分比。根据美国胸科学会的指导进行肺活量测定。通用的加性模型用于测试阈值效应。结果：在研究参与者中，有13％是目前吸烟者，38％是曾经吸烟者，49％从未吸烟。肺气肿百分比增加10点与左心室舒张末期容积（-4.1 ml; 95％置信区间[CI]，-3.3至-4.9; P <0.001），中风量（-2.7 ml）线性相关; 95％CI，-2.2至-3.3; P <0.001）和心输出量（-0.19升/分钟; 95％CI，-0.14至-0.23; P <0.001）。与以前的吸烟者和从未吸烟者相比，当前吸烟者中这些关联的影响更大。气流阻塞的程度与左心室的结构和功能相似，吸烟状态对这些关联的调节作用相似。肺气肿百分比和气流阻塞与左心室射血分数无关。结论：在一项基于人群的研究中，CT扫描发现更大程度的肺气肿和更严重的气流阻塞与左心室充盈受损，中风量减少和心输出量降低没有射血分数改变呈线性关系。
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