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Percutaneous Ablation for Atrial Fibrillation: The Role of Cross-sectional Imaging

¹ From the Department of Medical Imaging, Liège University Hospital, Sart Tilman B 35, B-4000 Liège, Belgium (B.G., D.S., D.D., R.F.D.); the Department of Medical Imaging, Rouen University Hospital, France (J.N.D.); and the Department of Cardiology, Maastricht Academic Hospital, the Netherlands (L.M.R., C.T.). Presented as an education exhibit at the 2002 RSNA scientific assembly. Received February 28, 2003; revision requested April 22 and received May 19; accepted May 29. Address correspondence to B.G. (e-mail: bghaye@chu.ulg.ac.be).

View larger version (49K): [in a new window]   Figure 1a.  Posterior (a) and superoinferior (b) views of the modal anatomy of the PVs, from a three-dimensional volume-rendered image data set obtained with contrast-enhanced multisection computed tomography (CT) (four sections, 2.5-mm collimation, 1.25-mm reconstruction interval) in a 45-year-old man prior to ablation therapy. Four independent ostia are visible in the dorsal aspect of the left atrium. Note that the right middle PV has a normal drainage into the central part of the right superior PV and that the lingular PV drains into the left superior PV. LI = left inferior, LS = left superior, RI = right inferior, RM = right middle, RS = right superior.

View larger version (40K): [in a new window]   Figure 1b.  Posterior (a) and superoinferior (b) views of the modal anatomy of the PVs, from a three-dimensional volume-rendered image data set obtained with contrast-enhanced multisection computed tomography (CT) (four sections, 2.5-mm collimation, 1.25-mm reconstruction interval) in a 45-year-old man prior to ablation therapy. Four independent ostia are visible in the dorsal aspect of the left atrium. Note that the right middle PV has a normal drainage into the central part of the right superior PV and that the lingular PV drains into the left superior PV. LI = left inferior, LS = left superior, RI = right inferior, RM = right middle, RS = right superior.

View larger version (47K): [in a new window]   Figure 2.  Schematic shows three variant configurations of the atrial-venous junction. The left PV branches are represented in blue and pink, and the left atrial wall is shown in orange. The normal pattern is pictured in B. Under- and overincorporation of pulmonary veins into the left atrial wall are shown in C and A, respectively. Divergent development of the cardiac anatomy results in variable lengths of the common trunk and variable numbers and morphology of ostia and PV branches.

View larger version (76K): [in a new window]   Figure 3a.  Preoperative single-section CT scans (5-mm collimation, 1-mm reconstruction interval, pitch of 2) obtained in a 53-year-old man with a type A dissecting thoracic aneurysm. Two-dimensional axial CT sections obtained from inferior (a) to superior (c) show a common retroatrial chamber formed by the confluence of the two inferior PVs. Note the clear delineation from the main left atrium. Compare this structure with the uniformly smooth posterior left atrial wall shown in Figure 1b. LI = left inferior, LS = left superior, RI = right inferior, RS = right superior.

View larger version (74K): [in a new window]   Figure 3b.  Preoperative single-section CT scans (5-mm collimation, 1-mm reconstruction interval, pitch of 2) obtained in a 53-year-old man with a type A dissecting thoracic aneurysm. Two-dimensional axial CT sections obtained from inferior (a) to superior (c) show a common retroatrial chamber formed by the confluence of the two inferior PVs. Note the clear delineation from the main left atrium. Compare this structure with the uniformly smooth posterior left atrial wall shown in Figure 1b. LI = left inferior, LS = left superior, RI = right inferior, RS = right superior.

View larger version (75K): [in a new window]   Figure 3c.  Preoperative single-section CT scans (5-mm collimation, 1-mm reconstruction interval, pitch of 2) obtained in a 53-year-old man with a type A dissecting thoracic aneurysm. Two-dimensional axial CT sections obtained from inferior (a) to superior (c) show a common retroatrial chamber formed by the confluence of the two inferior PVs. Note the clear delineation from the main left atrium. Compare this structure with the uniformly smooth posterior left atrial wall shown in Figure 1b. LI = left inferior, LS = left superior, RI = right inferior, RS = right superior.

View larger version (58K): [in a new window]   Figure 4.  Preablation baseline contrast-enhanced multisection CT scan (four sections, 2-mm collimation, 1-mm reconstruction interval) obtained in a 60-year-old woman shows the confluence of the left PVs. Volume-rendered posterior view shows a single ostium on the left side (*) and three distinct ostia on the right. LI = left inferior, LS = left superior, RI = right inferior, RM = right middle, RS = right superior.

View larger version (57K): [in a new window]   Figure 5a.  The most common variations in right middle lobe PV draining patterns are shown in volume-rendered posterior views obtained with single-section CT (2-mm collimation, 1-mm reconstruction interval, pitch of 2) before ablation in a 48-year-old woman (a) and a 51-year-old man (c) and obtained with contrast-enhanced multisection CT (four sections, 2.5-mm collimation, 1.25-mm reconstruction interval) before ablation in a 40-year-old man (b). In a, the drainage pathway from the right middle PV to the central portion of the right superior PV is visible; note the independent ostium in a right middle subsegmental vein, which drains into the left atrium (arrowhead). In b, the drainage pathway from the right middle PV to the left atrium via an independent ostium is shown. In c, drainage pathways from the right middle PV to the central portion of the right inferior PV, and from the lingular vein to the central portion of the left inferior PV, are depicted. LI = left inferior, LS = left superior, RI = right inferior, RM = right middle, RS = right superior.

View larger version (52K): [in a new window]   Figure 5b.  The most common variations in right middle lobe PV draining patterns are shown in volume-rendered posterior views obtained with single-section CT (2-mm collimation, 1-mm reconstruction interval, pitch of 2) before ablation in a 48-year-old woman (a) and a 51-year-old man (c) and obtained with contrast-enhanced multisection CT (four sections, 2.5-mm collimation, 1.25-mm reconstruction interval) before ablation in a 40-year-old man (b). In a, the drainage pathway from the right middle PV to the central portion of the right superior PV is visible; note the independent ostium in a right middle subsegmental vein, which drains into the left atrium (arrowhead). In b, the drainage pathway from the right middle PV to the left atrium via an independent ostium is shown. In c, drainage pathways from the right middle PV to the central portion of the right inferior PV, and from the lingular vein to the central portion of the left inferior PV, are depicted. LI = left inferior, LS = left superior, RI = right inferior, RM = right middle, RS = right superior.

View larger version (55K): [in a new window]   Figure 5c.  The most common variations in right middle lobe PV draining patterns are shown in volume-rendered posterior views obtained with single-section CT (2-mm collimation, 1-mm reconstruction interval, pitch of 2) before ablation in a 48-year-old woman (a) and a 51-year-old man (c) and obtained with contrast-enhanced multisection CT (four sections, 2.5-mm collimation, 1.25-mm reconstruction interval) before ablation in a 40-year-old man (b). In a, the drainage pathway from the right middle PV to the central portion of the right superior PV is visible; note the independent ostium in a right middle subsegmental vein, which drains into the left atrium (arrowhead). In b, the drainage pathway from the right middle PV to the left atrium via an independent ostium is shown. In c, drainage pathways from the right middle PV to the central portion of the right inferior PV, and from the lingular vein to the central portion of the left inferior PV, are depicted. LI = left inferior, LS = left superior, RI = right inferior, RM = right middle, RS = right superior.

View larger version (107K): [in a new window]   Figure 6a.  Percutaneous cryoablation in atrial fibrillation. (a) The cardiac catheter is inserted via the femoral vein and guided to the heart. (b) The catheter is inserted through the septum and into the left atrium. (c) The catheter enters the left upper pulmonary vein. (d) The cryoablation catheter is shown below the mapping Lasso catheter.

View larger version (98K): [in a new window]   Figure 6b.  Percutaneous cryoablation in atrial fibrillation. (a) The cardiac catheter is inserted via the femoral vein and guided to the heart. (b) The catheter is inserted through the septum and into the left atrium. (c) The catheter enters the left upper pulmonary vein. (d) The cryoablation catheter is shown below the mapping Lasso catheter.

View larger version (109K): [in a new window]   Figure 6c.  Percutaneous cryoablation in atrial fibrillation. (a) The cardiac catheter is inserted via the femoral vein and guided to the heart. (b) The catheter is inserted through the septum and into the left atrium. (c) The catheter enters the left upper pulmonary vein. (d) The cryoablation catheter is shown below the mapping Lasso catheter.

View larger version (101K): [in a new window]   Figure 6d.  Percutaneous cryoablation in atrial fibrillation. (a) The cardiac catheter is inserted via the femoral vein and guided to the heart. (b) The catheter is inserted through the septum and into the left atrium. (c) The catheter enters the left upper pulmonary vein. (d) The cryoablation catheter is shown below the mapping Lasso catheter.

View larger version (124K): [in a new window]   Figure 7a.  Asymptomatic PV stenoses in a 59-year-old man who underwent two sessions of RF ablation for atrial fibrillation. (a) Coronal maximum-intensity projection image, obtained with a three-dimensional gradient-echo MR angiographic sequence 9 months after the first session of RF ablation for atrial fibrillation in three PVs, shows slight stenosis (arrow) at the origin of the left superior PV. Note the normal origins (arrowheads) of the right superior and inferior PVs. (b) Coronal maximum-intensity projection image obtained with a three-dimensional gradient-echo MR angiographic sequence 3 months after the second session of RF ablation, this time involving all four PVs, shows moderate stenoses (arrows) at the origins of the left superior and right superior and inferior PVs.

View larger version (146K): [in a new window]   Figure 7b.  Asymptomatic PV stenoses in a 59-year-old man who underwent two sessions of RF ablation for atrial fibrillation. (a) Coronal maximum-intensity projection image, obtained with a three-dimensional gradient-echo MR angiographic sequence 9 months after the first session of RF ablation for atrial fibrillation in three PVs, shows slight stenosis (arrow) at the origin of the left superior PV. Note the normal origins (arrowheads) of the right superior and inferior PVs. (b) Coronal maximum-intensity projection image obtained with a three-dimensional gradient-echo MR angiographic sequence 3 months after the second session of RF ablation, this time involving all four PVs, shows moderate stenoses (arrows) at the origins of the left superior and right superior and inferior PVs.

View larger version (58K): [in a new window]   Figure 8a.  PV stenosis in a 40-year-old man who presented with mild chest discomfort and who had undergone RF ablation for atrial fibrillation in the left superior pulmonary vein 6 months earlier. Axial (a), axial oblique (b), and coronal oblique (c) views obtained with contrast-enhanced spiral CT show severe stenosis of the left superior pulmonary vein (arrow), associated with soft-tissue infiltration of surrounding fat. Note the multiple small lymph nodes (arrowhead in a and b). (Case courtesy of H. Page McAdams, MD, Duke University Medical Center, Durham, NC.)

View larger version (53K): [in a new window]   Figure 8b.  PV stenosis in a 40-year-old man who presented with mild chest discomfort and who had undergone RF ablation for atrial fibrillation in the left superior pulmonary vein 6 months earlier. Axial (a), axial oblique (b), and coronal oblique (c) views obtained with contrast-enhanced spiral CT show severe stenosis of the left superior pulmonary vein (arrow), associated with soft-tissue infiltration of surrounding fat. Note the multiple small lymph nodes (arrowhead in a and b). (Case courtesy of H. Page McAdams, MD, Duke University Medical Center, Durham, NC.)

View larger version (60K): [in a new window]   Figure 8c.  PV stenosis in a 40-year-old man who presented with mild chest discomfort and who had undergone RF ablation for atrial fibrillation in the left superior pulmonary vein 6 months earlier. Axial (a), axial oblique (b), and coronal oblique (c) views obtained with contrast-enhanced spiral CT show severe stenosis of the left superior pulmonary vein (arrow), associated with soft-tissue infiltration of surrounding fat. Note the multiple small lymph nodes (arrowhead in a and b). (Case courtesy of H. Page McAdams, MD, Duke University Medical Center, Durham, NC.)

View larger version (115K): [in a new window]   Figure 9a.  Thrombosis of the left upper PV in a 31-year-old man presenting with hemoptysis and transient discomfort of 3 months duration in the left side of the chest. RF ablation in the left superior PV had been performed for refractory atrial fibrillation 4 months earlier. The patient also received anticoagulant drug therapy. (a) Posteroanterior chest radiograph shows poorly demarcated opacities suggestive of asymmetric edema in the left upper lobe. (b, c) Axial contrast-enhanced CT scans (lung window) show diffuse ground-glass attenuation (arrows in b) and focal peripheral consolidation (arrow in c) in the left upper lobe, consistent with pulmonary venous infarction. Note the thickened interlobular septum (arrowhead in b) and the small pleural effusion. (d) Axial contrast-enhanced CT scan (mediastinal window) shows occlusion of the left superior PV (arrow), with soft-tissue attenuation surrounding the expected location of the vein. (Case courtesy of H. Page McAdams, MD, Duke University Medical Center, Durham, NC. Reprinted, with permission, from reference 5.)

View larger version (129K): [in a new window]   Figure 9b.  Thrombosis of the left upper PV in a 31-year-old man presenting with hemoptysis and transient discomfort of 3 months duration in the left side of the chest. RF ablation in the left superior PV had been performed for refractory atrial fibrillation 4 months earlier. The patient also received anticoagulant drug therapy. (a) Posteroanterior chest radiograph shows poorly demarcated opacities suggestive of asymmetric edema in the left upper lobe. (b, c) Axial contrast-enhanced CT scans (lung window) show diffuse ground-glass attenuation (arrows in b) and focal peripheral consolidation (arrow in c) in the left upper lobe, consistent with pulmonary venous infarction. Note the thickened interlobular septum (arrowhead in b) and the small pleural effusion. (d) Axial contrast-enhanced CT scan (mediastinal window) shows occlusion of the left superior PV (arrow), with soft-tissue attenuation surrounding the expected location of the vein. (Case courtesy of H. Page McAdams, MD, Duke University Medical Center, Durham, NC. Reprinted, with permission, from reference 5.)

View larger version (127K): [in a new window]   Figure 9c.  Thrombosis of the left upper PV in a 31-year-old man presenting with hemoptysis and transient discomfort of 3 months duration in the left side of the chest. RF ablation in the left superior PV had been performed for refractory atrial fibrillation 4 months earlier. The patient also received anticoagulant drug therapy. (a) Posteroanterior chest radiograph shows poorly demarcated opacities suggestive of asymmetric edema in the left upper lobe. (b, c) Axial contrast-enhanced CT scans (lung window) show diffuse ground-glass attenuation (arrows in b) and focal peripheral consolidation (arrow in c) in the left upper lobe, consistent with pulmonary venous infarction. Note the thickened interlobular septum (arrowhead in b) and the small pleural effusion. (d) Axial contrast-enhanced CT scan (mediastinal window) shows occlusion of the left superior PV (arrow), with soft-tissue attenuation surrounding the expected location of the vein. (Case courtesy of H. Page McAdams, MD, Duke University Medical Center, Durham, NC. Reprinted, with permission, from reference 5.)

View larger version (139K): [in a new window]   Figure 9d.  Thrombosis of the left upper PV in a 31-year-old man presenting with hemoptysis and transient discomfort of 3 months duration in the left side of the chest. RF ablation in the left superior PV had been performed for refractory atrial fibrillation 4 months earlier. The patient also received anticoagulant drug therapy. (a) Posteroanterior chest radiograph shows poorly demarcated opacities suggestive of asymmetric edema in the left upper lobe. (b, c) Axial contrast-enhanced CT scans (lung window) show diffuse ground-glass attenuation (arrows in b) and focal peripheral consolidation (arrow in c) in the left upper lobe, consistent with pulmonary venous infarction. Note the thickened interlobular septum (arrowhead in b) and the small pleural effusion. (d) Axial contrast-enhanced CT scan (mediastinal window) shows occlusion of the left superior PV (arrow), with soft-tissue attenuation surrounding the expected location of the vein. (Case courtesy of H. Page McAdams, MD, Duke University Medical Center, Durham, NC. Reprinted, with permission, from reference 5.)

View larger version (76K): [in a new window]   Figure 10a.  Pulmonary venous thrombosis and pulmonary infarction in a 48-year-old woman presenting with hemoptysis and pain in the left side of the chest. The patient had undergone successful RF ablation for recurring paroxysmal atrial fibrillation in the left superior pulmonary vein 4 months earlier. Fiber-optic bronchoscopy demonstrated hypervascular mucosa in the left upper lobe bronchus. A transesophageal echocardiogram was unremarkable. Chest radiographs (not shown) depicted alveolar areas of increased opacity in the left upper lobe. (a) Anterior perfusion lung scan shows hypoperfusion of the left lung. (The ventilation lung scan, which is not shown, was normal.) (b) Axial CT section shows increased attenuation, septal thickening (arrowhead), and rounded areas of consolidation (arrow) in the left upper lobe. (c) Axial contrast-enhanced CT scan shows stenosis and thrombosis in the left superior PV (arrow). (d) Coronal three-dimensional gradient-echo MR angiogram shows hypoperfusion of the left lung during the arterial phase. (e) Coronal venous phase three-dimensional gradient-echo MR angiogram shows hypoperfusion of the left lung, absence of venous flow in the left upper lobe, and thrombosis (arrow) of the left superior pulmonary vein. (f) Coronal maximum-intensity projection image obtained with a three-dimensional gradient-echo MR angiographic sequence shows hypoperfusion of the left lung and absence of venous flow in the left upper lobe.

View larger version (109K): [in a new window]   Figure 10b.  Pulmonary venous thrombosis and pulmonary infarction in a 48-year-old woman presenting with hemoptysis and pain in the left side of the chest. The patient had undergone successful RF ablation for recurring paroxysmal atrial fibrillation in the left superior pulmonary vein 4 months earlier. Fiber-optic bronchoscopy demonstrated hypervascular mucosa in the left upper lobe bronchus. A transesophageal echocardiogram was unremarkable. Chest radiographs (not shown) depicted alveolar areas of increased opacity in the left upper lobe. (a) Anterior perfusion lung scan shows hypoperfusion of the left lung. (The ventilation lung scan, which is not shown, was normal.) (b) Axial CT section shows increased attenuation, septal thickening (arrowhead), and rounded areas of consolidation (arrow) in the left upper lobe. (c) Axial contrast-enhanced CT scan shows stenosis and thrombosis in the left superior PV (arrow). (d) Coronal three-dimensional gradient-echo MR angiogram shows hypoperfusion of the left lung during the arterial phase. (e) Coronal venous phase three-dimensional gradient-echo MR angiogram shows hypoperfusion of the left lung, absence of venous flow in the left upper lobe, and thrombosis (arrow) of the left superior pulmonary vein. (f) Coronal maximum-intensity projection image obtained with a three-dimensional gradient-echo MR angiographic sequence shows hypoperfusion of the left lung and absence of venous flow in the left upper lobe.

View larger version (74K): [in a new window]   Figure 10c.  Pulmonary venous thrombosis and pulmonary infarction in a 48-year-old woman presenting with hemoptysis and pain in the left side of the chest. The patient had undergone successful RF ablation for recurring paroxysmal atrial fibrillation in the left superior pulmonary vein 4 months earlier. Fiber-optic bronchoscopy demonstrated hypervascular mucosa in the left upper lobe bronchus. A transesophageal echocardiogram was unremarkable. Chest radiographs (not shown) depicted alveolar areas of increased opacity in the left upper lobe. (a) Anterior perfusion lung scan shows hypoperfusion of the left lung. (The ventilation lung scan, which is not shown, was normal.) (b) Axial CT section shows increased attenuation, septal thickening (arrowhead), and rounded areas of consolidation (arrow) in the left upper lobe. (c) Axial contrast-enhanced CT scan shows stenosis and thrombosis in the left superior PV (arrow). (d) Coronal three-dimensional gradient-echo MR angiogram shows hypoperfusion of the left lung during the arterial phase. (e) Coronal venous phase three-dimensional gradient-echo MR angiogram shows hypoperfusion of the left lung, absence of venous flow in the left upper lobe, and thrombosis (arrow) of the left superior pulmonary vein. (f) Coronal maximum-intensity projection image obtained with a three-dimensional gradient-echo MR angiographic sequence shows hypoperfusion of the left lung and absence of venous flow in the left upper lobe.

View larger version (134K): [in a new window]   Figure 10d.  Pulmonary venous thrombosis and pulmonary infarction in a 48-year-old woman presenting with hemoptysis and pain in the left side of the chest. The patient had undergone successful RF ablation for recurring paroxysmal atrial fibrillation in the left superior pulmonary vein 4 months earlier. Fiber-optic bronchoscopy demonstrated hypervascular mucosa in the left upper lobe bronchus. A transesophageal echocardiogram was unremarkable. Chest radiographs (not shown) depicted alveolar areas of increased opacity in the left upper lobe. (a) Anterior perfusion lung scan shows hypoperfusion of the left lung. (The ventilation lung scan, which is not shown, was normal.) (b) Axial CT section shows increased attenuation, septal thickening (arrowhead), and rounded areas of consolidation (arrow) in the left upper lobe. (c) Axial contrast-enhanced CT scan shows stenosis and thrombosis in the left superior PV (arrow). (d) Coronal three-dimensional gradient-echo MR angiogram shows hypoperfusion of the left lung during the arterial phase. (e) Coronal venous phase three-dimensional gradient-echo MR angiogram shows hypoperfusion of the left lung, absence of venous flow in the left upper lobe, and thrombosis (arrow) of the left superior pulmonary vein. (f) Coronal maximum-intensity projection image obtained with a three-dimensional gradient-echo MR angiographic sequence shows hypoperfusion of the left lung and absence of venous flow in the left upper lobe.

View larger version (152K): [in a new window]   Figure 10e.  Pulmonary venous thrombosis and pulmonary infarction in a 48-year-old woman presenting with hemoptysis and pain in the left side of the chest. The patient had undergone successful RF ablation for recurring paroxysmal atrial fibrillation in the left superior pulmonary vein 4 months earlier. Fiber-optic bronchoscopy demonstrated hypervascular mucosa in the left upper lobe bronchus. A transesophageal echocardiogram was unremarkable. Chest radiographs (not shown) depicted alveolar areas of increased opacity in the left upper lobe. (a) Anterior perfusion lung scan shows hypoperfusion of the left lung. (The ventilation lung scan, which is not shown, was normal.) (b) Axial CT section shows increased attenuation, septal thickening (arrowhead), and rounded areas of consolidation (arrow) in the left upper lobe. (c) Axial contrast-enhanced CT scan shows stenosis and thrombosis in the left superior PV (arrow). (d) Coronal three-dimensional gradient-echo MR angiogram shows hypoperfusion of the left lung during the arterial phase. (e) Coronal venous phase three-dimensional gradient-echo MR angiogram shows hypoperfusion of the left lung, absence of venous flow in the left upper lobe, and thrombosis (arrow) of the left superior pulmonary vein. (f) Coronal maximum-intensity projection image obtained with a three-dimensional gradient-echo MR angiographic sequence shows hypoperfusion of the left lung and absence of venous flow in the left upper lobe.

View larger version (136K): [in a new window]   Figure 10f.  Pulmonary venous thrombosis and pulmonary infarction in a 48-year-old woman presenting with hemoptysis and pain in the left side of the chest. The patient had undergone successful RF ablation for recurring paroxysmal atrial fibrillation in the left superior pulmonary vein 4 months earlier. Fiber-optic bronchoscopy demonstrated hypervascular mucosa in the left upper lobe bronchus. A transesophageal echocardiogram was unremarkable. Chest radiographs (not shown) depicted alveolar areas of increased opacity in the left upper lobe. (a) Anterior perfusion lung scan shows hypoperfusion of the left lung. (The ventilation lung scan, which is not shown, was normal.) (b) Axial CT section shows increased attenuation, septal thickening (arrowhead), and rounded areas of consolidation (arrow) in the left upper lobe. (c) Axial contrast-enhanced CT scan shows stenosis and thrombosis in the left superior PV (arrow). (d) Coronal three-dimensional gradient-echo MR angiogram shows hypoperfusion of the left lung during the arterial phase. (e) Coronal venous phase three-dimensional gradient-echo MR angiogram shows hypoperfusion of the left lung, absence of venous flow in the left upper lobe, and thrombosis (arrow) of the left superior pulmonary vein. (f) Coronal maximum-intensity projection image obtained with a three-dimensional gradient-echo MR angiographic sequence shows hypoperfusion of the left lung and absence of venous flow in the left upper lobe.