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BackgroundChronic obstructive pulmonary disease (COPD) is associated with hemodynamic changes in the pulmonary vasculature. However, cardiac effects are not fully understood and vary by phenotype of chronic lower respiratory disease.PurposeTo use four-dimensional (4D) flow MRI for comprehensive assessment of the right-sided cardiovascular system, assess its interrater and intraobserver reproducibility, and examine associations with venous return to the right heart in individuals with chronic COPD and emphysema.Materials and MethodsThe Multi-Ethnic Study of Atherosclerosis COPD substudy prospectively recruited participants who smoked and who had COPD and nested control participants from population-based samples. Electrocardiography and respiratory gated 4D flow 1.5-T MRI was performed at three sites with full volumetric coverage of the thoracic vessels in 2014-2017 with postbronchodilator spirometry and inspiratory chest CT to quantify percent emphysema. Net flow, peak velocity, retrograde flow, and retrograde fraction were measured on 14 analysis planes. Interrater reproducibility was assessed by two independent observers, and the principle of conservation of mass was employed to evaluate the internal consistency of flow measures. Partial correlation coefficients were adjusted for age, sex, race/ethnicity, height, weight, and smoking status.ResultsAmong 70 participants (29 participants with COPD [mean age, 73.5 years ± 8.1 {standard deviation}; 20 men] and 41 control participants [mean age, 71.0 years ± 6.1; 22 men]), the interrater reproducibility of the 4D flow MRI measures was good to excellent (intraclass correlation coefficient range, 0.73-0.98), as was the internal consistency. There were no statistically significant differences in venous flow parameters according to COPD severity ( P > .05). Greater percent emphysema at CT was associated with greater regurgitant flow in the superior and inferior caval veins and tricuspid valve (adjusted r = 0.28-0.55; all P < .01), particularly in the superior vena cava.ConclusionFour-dimensional flow MRI had good-to-excellent observer variability and flow consistency. Percent emphysema at CT was associated with statistically significant differences in retrograde flow, greatest in the superior vena cava.© RSNA, 2019 Online supplemental material is available for this article. See also the editorial by Choe in this issue.

The authors modified Gianturco expandable metallic stents to make them relocatable. Two tandem designs were made. The first design had long struts and, thus, more evenly distributed expansive force; the second had short struts and more flexibility and was better suited for use in curved strictures. Both designs (two to four in tandem, 0.012-, 0.014-, and 0.018-inch wire) were tested successfully in vitro, and both designs (two to four in tandem, 0.012-inch wire) were successfully placed, retrieved, and relocated in the inferior vena cava of five dogs.

Hepatic panangiography was performed in 17 patients before and after side-to-side portacaval shunts. Preoperatively, a direct correlation existed between the diameters of the hepatic arteries and the severity of the patient's cirrhosis. Postoperatively, the splenic artery and vein and the hepatic artery dilated further in most patients, reflecting increased blood flow. The greatest increase occured in those patients with less severe cirrhosis. The liver shrank postoperatively in most patients. The corrected sinusoidal pressure dropped significantly in all patients. A unique pattern of sinusoidal filling at wedged hepatic venography was observed postoperatively in many of the patients.

To establish the value of the chest radiograph in assessing the hemodynamic status of the systemic circulation, the vascular pedicle width ( VPW ) and vena azygos width (AW) were correlated with total blood volume (TBV) and other parameters in 61 cardiac patients. In both ischemic and valvular cardiac disease a highly significant linear correlation was found between VPW and TBV (r = 0.80, p less than 0.001). In patients with dilated neck veins VPW was greater than 62 mm (normal 48 +/- 5 mm). A less significant correlation was found between VPW and mean right atrial pressure ( MRAP ). Change in VPW correlated strongly (r = 0.93, p less than 0.001) with change in TBV (0.5-cm change in VPW = 1.0-liter change in TBV). Correlation between AW and TBV was poor (r = 0.50, p less than 0.01), but between AW and MRAP the correlation was stronger (r = 0.74, p less than 0.001). Changes in AW usually occurred in the same direction as changes in MRAP , but the correlation was not significant (r = 0.45). VPW and AW did not correlate with pulmonary blood volume, pulmonary arterial pressure, stroke volume, or heart rate. Radiologic assessment of VPW and AW adds an additional clinically useful dimension to the evaluation of cardiac disease.

The widths of the systemic vessels extending from the thoracic inlet to the heart (the vascular pedicle) and of the azygos vein were measured in 83 normal volunteers and 42 patients with cardiac disease. Mean vascular pedicle width ( VPW ) (erect) was 48 +/- 5.0 mm and correlated well with body weight (r = 0.64) and surface area (r = 0.62). Rotation to the left reduced VPW and to the right increased it. Inspiration and expiration caused little change. The supine VPW increased an average of 20% (47 +/- 37% to the compliant venous right side and 7 +/- 48% to the less compliant arterial left). Supine azygos width (AW) increased 105 +/- 47%. Mean erect AW was 5.14 +/- 1.36 mm. AW did not correlate significantly with anthropomorphic characteristics. Because VPW correlates with the patient's physique, its normality can be estimated within clinically useful limits by inspection. Since AW has no such correlation, serial changes are of more value than initial absolute values.

A case of rare venous calcifications involving cavernous transformation of the portal vein and spontaneous splenocaval shunt is presented. Findings were obtained with plain abdominal radiography, computed tomography, and angiography. Inflammation of the portal vein with subsequent occlusion could account for splenomegaly and hypertrophy of the splenic artery and vein with atheromatous calcifications due to turbulence and sclerosis. Angiography is essential prior to surgical intervention in order to select the appropriate shunt.

Magnetic resonance (MR) imaging was performed in 53 patients considered to be candidates for a modified Fontan operation to repair cardiac or extracardiac vascular anomalies. The MR studies were reviewed retrospectively, and the findings with regard to the extracardiac vascular anatomy were compared with the findings from angiography or surgery. The accuracy of MR for the correct identification of the systemic veins was 98%; for pulmonary arteries, 97%; and for pulmonary veins, 95%. For identification of pulmonary veins, MR imaging had a sensitivity of 90% and a specificity of 100%. MR provides excellent demonstration of the extracardiac vascular structures, which are of particular importance in patients being considered for a Fontan procedure.