Preliminary reports of noninvasive accurate method to measure pulmonary vascular capacity in normal volunteers / 中国应用生理学杂志

<p><b>OBJECTIVE</b>Because the traditional loop of breathing control and regulation effect on blood circulation, there was rare study of pulmonary vein capacity. We need a noninvasive and accurate pulmonary vascular capacity measurement and analysis method.</p><p><b>METHODS</b>Twelve normal volunteers were performed a total lung CT scan, image data analysis processing by computer software, the whole lungs from the apex to the base of lung with 40-50 layers by hand-cut, the connection between adjacent layers automatically by a computer simulation, the full pulmonary vascular (≥ 0.6 mm) were treated by high-accuracy three-dimensional imaging technology after removing the interference, and then calculate the whole lung and pulmonary vascular.</p><p><b>RESULTS</b>The whole lung of the 12 normal volunteers from the apex to the base of lung CT scan image layers was 530 ± 98 (range, 431-841). The total capacity of lung and pulmonary vascular blood was 3705 ± 857 (range, 2398-5383) ml, and the total volume of the pulmonary vascular blood was 125 ± 32 (range, 94-201) ml. The pulmonary vein vascular blood volume was 63 ± 16 (range, 47-100) ml.</p><p><b>CONCLUSION</b>The method of measuring the three-dimensional imaging of pulmonary vascular capacity by analyzing lung CT scan data is available and accurate.</p>

Normal reference values and predict equations of heart function / 中国应用生理学杂志

<p><b>OBJECTIVE</b>For heart functional parameters, we commonly used normal range. The reference values and predict formulas of heart functional parameters and their relationships with individual characteristics are still lack.</p><p><b>METHODS</b>Left ventricular (LV) volumes (end-diastolic volume and end-systolic volume), stroke volume (SV), ejection fraction (EF) and cardiac output (CO) were measured by cardiac CT angiography (CAT) in 1 200 healthy Caucasian volunteers, men 807 and women 393, and age 20-90yr. The results are analyzed by high-accuracy three-dimensional imaging technology, and then measured the dynamic changes of the volumes of each atriam and ventricule during their contractions and relaxations. The gender, age, height and weight were analyzed by multiple linear regression to predict LV functional parameters.</p><p><b>RESULTS</b>Except the LVEF was lower in man than in women (P < 0.001), all other LV functional parameters of EDV, ESV, SV, FE and CO were higher in man (P < 0.001). Multiple linear regression indicated that age, gender, height and weight are all independent factors of EDV, ESV and SV (P < 0.001). CO could be significantly predicted by age, gender and weight (P < 0.001), but not height (P > 0.05). The predict equation for CO (L x min(-1)) = 6.963+0.446 (Male) -0.037 x age (yr) +0.013 x weight (kg).</p><p><b>CONCLUSION</b>Age, gender, height and weight are predictors of heart functions. The reference values and predict equations are important for noninvasive and accurate evaluation of cardiovascular disease and individualized treatment.</p>

The correlation of the stroke volume with pulmonary venous volume and left atrial volume / 中国应用生理学杂志

<p><b>OBJECTIVE</b>The same person's pulmonary venous blood volume, left atrial volume and stroke volume were measured by lung CT scans and cardiac CT angiography (CTA). Then their relationships were analyzed in order to investigate the mechanism of breathing control.</p><p><b>METHODS</b>As we described before, full pulmonary vascular (-0.6mm) volume was accurately calculated by three-dimensional imaging technology from lung CT scan; left atrial volume and stroke volume of left ventricle were calculated from the CTA data. Then the relationships among them were analyzed for estimation of the lung-artery time.</p><p><b>RESULTS</b>The total volume of lung and pulmonary vascular blood was 3486 ± 783 (2156-4418) ml, and the pulmonary vascular blood volume was 141 ± 20 (105-163) ml. The estimated pulmonary venous volume was 71 ± 10 (52-81) ml. Left atrial volume at the end diastolic was 97 ± 39 (53-165) ml, Stroke volume of left ventricle was 86 ± 16 (60-106) ml. Pulmonary venous volume and the left atrial volume were double of stroke volume(1.7-2.4).</p><p><b>CONCLUSION</b>The estimated lung-artery time was three heart beat.</p>