Bronchopulmonary shunts in patients with chronic thromboembolic pulmonary hypertension: evaluation with helical CT and MR imaging.

OBJECTIVE The purpose of our study was to compare differences in flow between the pulmonary and systemic circulations by assessing MR phase-contrast flow measurements and CT measurements of dilated bronchial arteries in patients with chronic thromboembolic pulmonary hypertension. MATERIALS AND METHODS Seventeen patients were included in this study. MR phase-contrast flow measurements were used to calculate the net forward volumes in the right and left pulmonary arteries and in the ascending aorta. Single-detector helical CT scans were assessed for the presence of dilated bronchial arteries that could be delineated from the descending aorta to the mainstem bronchi. Their perpendicular cross-sectional area at the level of the main bronchi was measured using a double-threshold region of interest (> or =100-3072 H). RESULTS The mean net forward volume in the aorta was 44.6 mL per heartbeat (R-R interval) and in the pulmonary arteries, 30 mL per R-R interval. Thus, the mean difference was 14.6 mL per R-R interval; this value represents the shunt volume between the systemic arterial and pulmonary venous circulations. On CT, dilated bronchial arteries were depicted in all patients (mean, three arteries per patient). The mean cross-sectional area of the bronchial arteries was 0.19 cm(2). Pearson's correlation coefficient (r) between cross-sectional area and shunt volume was 0.86 (p < 0.01). CONCLUSION MR imaging was able to reveal substantial differences in flow between the systemic arterial and pulmonary venous circulations in patients with chronic thromboembolic pulmonary hypertension. These differences correlated well with the diameters of the bronchial arteries seen on helical CT. Furthermore, these differences resolved after pulmonary thromboendarterectomy. MR imaging enables the accurate estimation of flow in the bronchial arteries in patients with chronic thromboembolic pulmonary hypertension.

[1]  U. Kuhlmann,et al.  [The significance of bronchial circulation in pulmonary hypertension]. , 1988, Der Internist.

[2]  S. Orell,et al.  Anastomoses between bronchial and pulmonary arteries in pulmonary thromboembolic disease. , 1966, Acta pathologica et microbiologica Scandinavica.

[3]  M. Calabresi,et al.  The simultaneous estimation of right and left ventricular outputs applied to a study of the bronchial circulation in patients with chronic lung disease. , 1959, American heart journal.

[4]  D N Firmin,et al.  Quantitation of antegrade and retrograde blood flow in the human aorta by magnetic resonance velocity mapping. , 1989, American heart journal.

[5]  W. Neches,et al.  Pulmonary perfusion defect and bronchial artery collateral blood flow. , 1977, JAMA.

[6]  M. Thelen,et al.  Hemodynamic effects of nonionic contrast bolus injection and oxygen inhalation during pulmonary angiography in patients with chronic major-vessel thromboembolic pulmonary hypertension. , 1996, Circulation.

[7]  N. Hayat,et al.  Comparison of bronchopulmonary collaterals and collateral blood flow in patients with chronic thromboembolic and primary pulmonary hypertension. , 1997, Heart.

[8]  P. Mchenry,et al.  Myocardial Blood Flow in Man as Measured by a Coincidence Counting System and a Single Bolus of 84RbCl , 1967, Circulation.

[9]  F. Bonnel,et al.  Thoracic helical CT: influence of subsecond scan time and thin collimation on evaluation of peripheral pulmonary arteries , 2000, European Radiology.

[10]  C. Higgins,et al.  Pulmonary hypertension: pulmonary flow quantification and flow profile analysis with velocity-encoded cine MR imaging. , 1992, Radiology.

[11]  Velocity‐encoded, phase‐difference cine MRI measurements of coronary artery flow: Dependence of flow accuracy on the number of cine frames , 1996, Journal of magnetic resonance imaging : JMRI.

[12]  I. Mandelbaum.  Bronchial Circulation during Cardiopulmonary Bypass , 1966, Annals of surgery.

[13]  A. B. Malik,et al.  Bronchovascular adjustments after pulmonary embolism. , 1980, Journal of applied physiology: respiratory, environmental and exercise physiology.

[14]  S. Mohr-Kahaly,et al.  [Reversibility of changes in left and right ventricular geometry and hemodynamics in pulmonary hypertension. Echocardiographic characteristics before and after pulmonary thromboendarterectomy]. , 1997, Zeitschrift fur Kardiologie.

[15]  Spiral CT of Pulmonary Hypertension and Chronic Thromboembolism , 1997, Journal of thoracic imaging.

[16]  S. Lakshminarayan,et al.  The bronchial circulation. Small, but a vital attribute of the lung. , 1987, The American review of respiratory disease.

[17]  P. Paré,et al.  Bronchopulmonary anastomotic and noncoronary collateral blood flow in humans during cardiopulmonary bypass. , 1985, Chest.

[18]  M. Calabresi,et al.  The simultaneous estimation of right and left ventricular outputs applied to a study of the bronchial circulation in dogs. , 1959, American heart journal.

[19]  H. Kauczor,et al.  Kontrastmittelverstärkte dreidimensionale MR-Angiographie der Lungenarterien bei Patienten mit chronisch-rezidivierender Lungenembolie - Vergleich mit der selektiven intraarteriellen DSA , 2000 .

[20]  B. Ohnesorge,et al.  Diagnostik der Lungenembolie mit der Mehrschicht-Spiral-CT , 2001, Der Radiologe.

[21]  M. Reiser,et al.  Beurteilung der Rechtsherzbelastung in der Spiral-CT bei Patienten mit akuter Lungenembolie , 1999 .

[22]  Tobin Ce.  The bronchial arteries and their connections with other vessels in the human lung. , 1952 .

[23]  H. Kauczor,et al.  Update on diagnostic strategies of pulmonary embolism , 1999, European Radiology.

[24]  K. Kreitner,et al.  Flußquantifizierung von intrakardialen Shuntvolumina unter Verwendung der MR-Phasenkontrast-Technik in Atemanhaltephase , 1998 .

[25]  Berthold B. Wein,et al.  Farbkodierte Darstellung des Lungenparenchyms bei vermuteter Lungenembolie mittels Mehrschicht-Spiral-CT , 2001 .

[26]  H. Kauczor,et al.  Spiral CT of Bronchial Arteries in Chronic Thromboembolism , 1994, Journal of computer assisted tomography.

[27]  K. Pump.  Distribution of bronchial arteries in the human lung. , 1972, Chest.

[28]  U. Kuhlmann,et al.  Die Bedeutung der Bronchialzirkulation bei pulmonaler Hypertonie , 1988 .

[29]  A. Mizushima,et al.  Helical CT imaging of bronchial arteries with curved reformation technique in comparison with selective bronchial arteriography: preliminary report. , 1996, Journal of computer assisted tomography.

[30]  C. Higgins,et al.  Right and left lung perfusion: in vitro and in vivo validation with oblique-angle, velocity-encoded cine MR imaging. , 1991, Radiology.

[31]  W. Auger,et al.  Chronic major-vessel thromboembolic pulmonary hypertension. , 1990, Circulation.

[32]  R. Virchow,et al.  Gesammelte Abhandlungen zur wissenschaftlichen Medicin , 1856 .

[33]  B. Brundage,et al.  Pulmonary hypertension from chronic pulmonary thromboembolism. , 1988, Annals of internal medicine.