- Email: [email protected]
Transcatheter patch correction of secundum atrial septal defects
Transcatheter Patch Correction of Secundum Atrial Septal Defects Eleftherios B. Sideris, MD, Savvas Toumanides, MD, Benjamin Macuil, MD, Hugo Gutierrez-Leonard, MD, Manolis Poursanov, MD, Alexander Sokolov, MD, and Spyridon D. Moulopoulos, MD The efficacy and safety of the transcatheter patch (TP) correction of a secundum atrial septal defect (ASD) was studied acutely and on short-term follow-up in 20 patients, successfully implanted with the device. TPs are made of polyurethane foam and require temporary balloon catheter immobilization on the atrial septum for 48 hours. Eighteen patients were not suitable for disk-device repair. The patient median age and ASD diameter were 37 years and 26 mm, respectively. Eighteen patients had immediate effective ASD occlusion; 2 patients had significant residual shunts. Premature leaks of the supportive balloons were responsible for the residual shunts. One of the patients with residual shunt received
a second patch 6 months later with full occlusion. All patients with implants were doing well up to 24 months after implantation. Existing symptoms improved although residual shunts remained; septal anatomy was normalized, with the patched area becoming progressively indistinguishable from the rest of the septum. In conclusion, TP occlusion of secundum ASD is feasible and effective even for defects unsuitable for disk-device repair. The method appears safe acutely and on shortterm follow-up, with symptomatic improvement and normalization of septal anatomy. 䊚2002 by Excerpta Medica, Inc. (Am J Cardiol 2002;89:1082–1086)
isk device occlusion has emerged as an alternative to surgery for closure of an atrial septal D defect (ASD) ; it is mostly effective in the occlusion
cover the distal balloon entirely with the exception of the catheter entry (Figure 1B). The distal balloon was inflated at a diameter 2 mm larger than the defect. A 2-mm nylon loop sutured at the apical internal surface of the patch was connected with a double nylon thread for retrieval/retraction purposes (Figure 1). Radiopaque thread (Netco, Hudson, Massachusetts) was sutured on the patch. Supporting balloon catheters: Custom-made, double-latex balloons (NuMed Inc.) were used in 18 cases. Single- sized balloons (NuMed Inc.) with floppy proximal Nitinol wires (Ft. Wayne Metals, Fort Wayne, Indiana) were used in 2 cases.
1–3
of small-to-moderate secundum ASDs without the need of thoracotomy or cardiopulmonary bypass. Device-related problems have been found both during implantation and long-term follow-up4,5; most devicerelated problems, including wire fractures and embolization,5,6 atrial perforation, and valve leaflet perforation,3,5 are wire related because all devices require metal skeleton wires.5,6 The long-term effects of such wires or alloys are unknown; however, carcinogenicity, coronary spasm, tissue necrosis, and allergic reactions related to their nickel content have been implicated.7 Toxic nickel levels have been found acutely with certain devices8; chronic nickel leaching is not unlikely with inevitable metal corrosion.9 The transcatheter patch (TP) ASD correction could theoretically improve on both the surgical morbidity and the disk-device–related problems of ASD occlusion.
METHODS
Transcatheter patch: Transcatheter patches were tailored from polyurethane foam (Foamex-EddystonePenn) and were supported by custom made double or single balloon catheters (NuMed Inc., Hopkinton, New York). A sleeve-type patch was constructed to From the Athenian Institute of Pediatric Cardiology and the Department of Clinical Therapeutics, University of Athens, Athens, Greece; The Military Hospital, Mexico City, Mexico; the Bakulev Institute, Moscow, Russia; and the Cardiology Institute, Tomsk, Russia. Manuscript received November 8, 2001; revised manuscript received and accepted January 18, 2002. Address for reprints: Eleftaherios B. Sideris, MD, Pediatric Cardiology, 1600 Coulter #200, Amarillo, Texas, 79106. E-mail: [email protected].
1082
©2002 by Excerpta Medica, Inc. All rights reserved. The American Journal of Cardiology Vol. 89 May 1, 2002
METHODS The procedures were performed after informed consents were obtained from all patients according to the regulations of each participating institution. Twenty patients underwent successful implantation of a transcatheter patch for ASD occlusion; in 2 additional patients, the balloon/patch was not permanently implanted but was retrieved percutaneously for various reasons. Eighteen of the 20 patients were unsuitable for disk-device occlusion because of either a deficient rim/and or ASD size too large for the septal size. The septal rim was assessed by transesophageal echocardiography in the anterior, superior, and inferior dimensions; we defined the septal rim as deficient if it was ⬍5 mm in any of the measured dimensions. There were 9 defects with deficient anterior rims, 3 defects with deficient superior rims, and 6 defects with deficient inferior rims. Two young patients had defects too large for their atrial septal size to receive the appropriate size of disk device. Two patients were unsuitable for disk-device occlusion, 1 with multiple septal fenestrations. All pa0002-9149/02/$–see front matter PII S0002-9149(02)02280-4
FIGURE 1. A, transcatheter patch (sleeve type) with a double-balloon catheter: The patch (P) is mounted on the distal balloon (DB) of the double-balloon catheter. A nylon thread (ny) is attached to the patch. B, diagram of a double-balloon sleeve patch occlusion (1) and patch release (2). Occlusion involved inflation of the distal balloon/patch in the left atrium first, opposite the defect, and inflation of the proximal balloon. Release involved deflation of the distal and proximal balloons, removal of the balloon catheter, and release of the patch after pulling the double nylon thread as a single strand. PB ⴝ proximal balloon.
FIGURE 2. Left atrial histologic examination of a piglet 48 hours after implantation: Fibrin (F) and inflammatory cells are responsible for attachment of the polyurethane (POL) to the septum (SEP).
tients had significant left-to-right shunts with Qp:Qs 1.5 to 4.0 (median 2.5); 3 patients also had pulmonary hypertension, with systolic pulmonary artery pressure 40 to 55 mm Hg. The patient age ranged from 7 to 65 years (median 37), and the defect size, from 13 to 34 mm (median 26). Patient weight varied between 22 and 90 kg (median 52). All defects with the exception of 1 with multiple fenestrations were single. They were repaired using transcatheter patches supported by double balloons in 18 cases and single distal balloons with proximal floppy disks in 2 cases. Large patches delivered through 12Fr to 13Fr sheaths were used in 18 cases. Small patches delivered through 10Fr sheaths were used for the remaining cases (small balloon/patches can be used for defects up to 15 mm and large ones for all other sizes). The method can be summarized in the following steps: 1. A multipurpose catheter is crossed over the defect and is placed in the left upper pulmonary vein; the catheter is exchanged with an 0.25-inch extra-stiff exchange wire. 2. A large balloon catheter (Meditech, Watertown, Massachusetts, or NuMed) is placed over the wire; balloon sizing, as well as balloon test occlusion of the defect, is performed. Balloon occlusion is performed
under blood pressure/heart rate monitoring and under transesophageal echocardiography; a good candidate for patch occlusion is the patient who has full occlusion of the defect without impairment of pulmonary venous return or the mitral inflow. 3. A sheath of an appropriate length is selected (it should be long enough to reach the left atrium. 4. The patch is provided preloaded in a 10-cm bypass sheath that is the same size as the introducing sheath. It is positioned over the exchange wire through the hemostat valve of the long sheath and is flushed thoroughly; it is released at the level of the inferior vena cava. Subsequently the patch is advanced over the wire in the left atrium. Heparin (100 U/kg or no more than 5,000 U) is administered. Antibiotics (cephalosporins) are given prophylactically for 36 hours. 5. The distal balloon/patch is inflated with dilute contrast at a diameter 2 mm larger than the occluding diameter of the defect. The catheter with the inflated balloon/patch is pulled over the wire to the atrial septum where the defect is occluded. Transesophageal echocardiography and fluoroscopy are required; full occlusion needs to be demonstrated. 6. The proximal balloon is inflated in the right atrium with dilute contrast, at the same diameter as the distal balloon. The wire is extracted. 7. Both the end of the long sheath and the balloon catheter are immobilized by suture and tape outside the groin. The patient is moved to his/her room (or the intensive care unit) with monitoring. The patient is allowed to move in bed but not ambulate. 8. Careful transthoracic echocardiography is required in 24 hours. The diameters of the supporting balloons are verified; the patch should be immobile on the septum. 9. Patch release is done under echocardiography 48 hours after implantation. The groin area with the catheter and sheath endings is cleaned thoroughly with Betadine. The distal balloon is deflated first, followed by the proximal balloon; the entire balloon catheter is then withdrawn. With the tip of the sheath against the patch, the double nylon tie attached to the patch is withdrawn as a single strand releasing the patch.
CONGENITAL HEART DISEASE/TRANSCATHETER PATCH CORRECTION OF ASDs
1083
FIGURE 3. A, 34-mm secundum ASD with deficient inferior rim () rim in an adult patient. B, transcatheter patch (P) is released 48 hours after implantation with small residual shunt. C, effective clinical occlusion with a remaining small residual shunt (RS) remaining at 6-month follow-up. LA ⴝ left atrium; RA ⴝ right atrium.
The patch is radiopaque, echogenic, and retractable in the introducing sheath until release.
RESULTS Twenty-two patients were taken to the catheterization laboratory with the intention to treat. Twenty of them had TPs permanently implanted. Two balloons gradually lost their volumes with significant residual shunts upon release (48 hours). Five patients had trivial residual shunts. The balloon patch was detected to be away from the septum by echocardiography at 24 hours in 1 patient. It was pulled to the septum from the groin and was immobilized again, with an excellent result after release (48 hours). All patients with implants were doing well up to 24 months after implantation. One patient with a significant residual shunt received a second patch 6 months after the first implantation, with full occlusion of the defect. On echocardiography, the transcatheter patches were seen to be progressively flatter and practically indistinguishable from the rest of the septum. Most trivial residual shunts did not disappear on follow-up. 1084 THE AMERICAN JOURNAL OF CARDIOLOGY姞
VOL. 89
DISCUSSION Transcatheter occlusion of ASD by disk devices can be an effective outpatient procedure for some secundum ASDs.4,5 However, all disk devices are made with a metal skeleton frame with many acute and possibly long-term complications.10 The described method of transcatheter patch placement could avoid some of the problems of surgery and ASD device repair, because it does not require thoracotomy or sutures for its placement and there is no permanent metal implantation. Ideal TP material should be thin and porous for fast endothelialization. The polyurethane foam fulfilled the above criteria, requiring only 48 hours of temporary support in experimental studies.11 Fibrin and inflammatory cells were shown to be responsible for early septal attachment (Figure 2). The tailoring of the patch can take many desired shapes, including the shape used in this study. Retrievability of the patch during introduction and before withdrawal of the supportive catheters is possible and very important for the safety of the procedure because it was seen in the 2 MAY 1, 2002
FIGURE 4. A, 26-mm ASD secundum with deficient anterior rim (ant) in a 42-year-old patient, by transesophageal echocardiography (longitudinal view). B, transcatheter patch (p) is released 48 hours after implantation; the patch is not only attached to the rim of the defect, but is also attached at the right and left atrial sides (same atrial orientation). C, 1 year after implantation the patch has flattened further and can hardly be distinguished from the rest of the septum; the full occlusion is maintained. Abbreviations as in Figure 3.
abandoned cases; the addition of the radiopaque thread in the construction of the patch helps both optimal position and possible retrieval. The supportive catheter could have several designs, including balloon and floppy wire(s) or double balloon. Theoretically, the double-balloon support could be more secure, particularly for large defects. The possible advantages of the transcatheter patch over the disk devices can be summarized as follows: (1) lack of wire-related problems; (2) increased spectrum of application (less rim requirement); and (3) increased safety features. The TP is a balloon-delivered device with similar advantages to the detachable balloon devices12,13 but with improved safety features.11 The safety features include: (1) no embolization because of intracardiac and outside body support (the operator has total control until the patch is attached to the atrial septum); (2) avoidance of the long sheath air entrapment and air embolization in the coronary arteries (the patch is
delivered in the left atrium over a wire); and (3) a readily retractable and retrievable TP through the introducing sheath. Test occlusion is of paramount importance in predicting the TP result. It should cause full occlusion without impairment of mitral or pulmonary vein flow and no decrease in cardiac output. In situations in which no full occlusion can be achieved during test occlusion, another device with more overlapping should be chosen; the use of multiple TPs is also possible. The importance of full test occlusion before TP placement can also be supported from our early follow-up observations in patients with trivial, small residual shunts. These shunts do not appear to disappear with time, in contrast to disk devices with significant overlapping (Figure 3). A positive follow-up observation was the remodeling of the ASD area with progressive flattening of the patch; the patch area could hardly be distinguished from the rest of the septum (Figure 4). Premature leakage of supportive
CONGENITAL HEART DISEASE/TRANSCATHETER PATCH CORRECTION OF ASDs
1085
balloons in 2 patients was the only device-related problem noticed; although the dilute contrast leakage was not dangerous for patients, it resulted in suboptimal occlusions. Construction of more durable balloons is obviously important. The importance of 24-hour echocardiographic follow-up was demonstrated in 1 patient whose distal balloon was seen away from the septum; it was repositioned and further immobilized from outside, with an excellent result after release. The need for 48-hour hospitalization is an obvious disadvantage of the method. However, it was well tolerated by patients, even the younger patients. No anticoagulation was needed after implantation except for acetylsalicylic acid; the continuous use of anticoagulation is contraindicated because it interferes with the fibrin formation and attachment of the patch to the septum. The introduction area should be covered carefully and antibiotics should be given to prevent infection. Acknowledgment: We would like to thank Chrysoula E. Sideris, RN, for her continuous and dedicated assistance in the animal laboratory, Professor S. Stamatelopoulos, Chairman of the Department of Clinical Therapeutics University of Athens, for his advice and guidance, Professor Bagrat Alekyan of the Bakulev Institute in Moscow for his support and trust in the method, Professor Shipulin of the Department of Cardiovascular Surgery, Tomsk, Russia, for his support, Victor Varvarenko, MD, of the Tomsk Cardiovascular
1086 THE AMERICAN JOURNAL OF CARDIOLOGY姞
VOL. 89
Institute for his assistance, and M. Somarriba, MD, of the Military Hospital, Mexico City, Mexico. 1. King T, Mills N. Nonoperative closure of atrial septal defects. Surgery 1974;75:383–386. 2. Rashkind W, Cuaso C. Transcatheter treatment of congenital heart disease. Circulation 1983;67:711–716. 3. Sideris E, Sideris S, Thanopoulos B, Ehly R, Fowlkes J. Transvenous atrial septal defect occlusion by the “buttoned” device. Am J Cardiol 1990;123:191– 200. 4. Rao PS, Sideris E, Hausdorf G, Rey C, Lloyd T, Beekman R, Worms AM, Bourlon F, Onorato E, Khalilulllah M, Haddad J. International experience with secundum atrial septal defect occlusion by the buttoned device. Am Heart J 1994;128:1022–1035. 5. Prieto LR, Foreman CK, Cheatham JP, Latson LA. Intermediate -term outcome of transcatheter secundum atrial septal defect closure, using the Bard Clamshell septal occluder. Am J Cardiol 1996;78:1310 –1313. 6. Sievert H, Babic M, Ensslen R. Transcatheter closure of large atrial septal defects with the Babic system. Cathet Cardiovasc Diagn 1995;36:232–240. 7. Sunderman FW. A review of the metabolism and toxicology of Nickel. Ann Clin Lab Sci 1977;7:377–398. 8. Ries M, Kampmann C, Meyer J. Nickel release in patients with atrial septal defects after the implantation of the Amplantzer septal occluder (abstr). Circulation 2000;102(suppl II):II–767. 9. Guidoin R, Marois V, Douville Y. First generation aortic endografts: analysis of explanted Stentor devices from the Eurostar Registry. J Endovasc Ther 2000;7:105–122. 10. Agarwal S, Ghosh P, Mittal P. Failure of devices used for closure of atrial septal defects, mechanisms and management. J Thorac Cardiovasc Surg 1996; 112:226 –229. 11. Sideris E, Toumanides S, Alekyan B, Varvarenko V, Stamatelopoulos S, Moulopoulos S. Transcatheter patch correction of atrial septal defects: experimental validation and early clinical experience (abstr). Circulation 2000; 102(suppl II):II–588. 12. Sideris E, Kaneva A , Sideris C, Moulopoulos S. Transcatheter atrial septal defect occlusion in piglets by balloon detachable devices. Cathet Cardiovasc Intervent 2000;51:529 –534. 13. Sideris EB, Chiang CW, Zhang JC, Wang WS. Transcatheter correction of heart defects by detachable balloon buttoned devices: a feasibility study (abstr). J Am Coll Cardiol 1999;23:528A.
MAY 1, 2002
a second patch 6 months later with full occlusion. All patients with implants were doing well up to 24 months after implantation. Existing symptoms improved although residual shunts remained; septal anatomy was normalized, with the patched area becoming progressively indistinguishable from the rest of the septum. In conclusion, TP occlusion of secundum ASD is feasible and effective even for defects unsuitable for disk-device repair. The method appears safe acutely and on shortterm follow-up, with symptomatic improvement and normalization of septal anatomy. 䊚2002 by Excerpta Medica, Inc. (Am J Cardiol 2002;89:1082–1086)
isk device occlusion has emerged as an alternative to surgery for closure of an atrial septal D defect (ASD) ; it is mostly effective in the occlusion
cover the distal balloon entirely with the exception of the catheter entry (Figure 1B). The distal balloon was inflated at a diameter 2 mm larger than the defect. A 2-mm nylon loop sutured at the apical internal surface of the patch was connected with a double nylon thread for retrieval/retraction purposes (Figure 1). Radiopaque thread (Netco, Hudson, Massachusetts) was sutured on the patch. Supporting balloon catheters: Custom-made, double-latex balloons (NuMed Inc.) were used in 18 cases. Single- sized balloons (NuMed Inc.) with floppy proximal Nitinol wires (Ft. Wayne Metals, Fort Wayne, Indiana) were used in 2 cases.
1–3
of small-to-moderate secundum ASDs without the need of thoracotomy or cardiopulmonary bypass. Device-related problems have been found both during implantation and long-term follow-up4,5; most devicerelated problems, including wire fractures and embolization,5,6 atrial perforation, and valve leaflet perforation,3,5 are wire related because all devices require metal skeleton wires.5,6 The long-term effects of such wires or alloys are unknown; however, carcinogenicity, coronary spasm, tissue necrosis, and allergic reactions related to their nickel content have been implicated.7 Toxic nickel levels have been found acutely with certain devices8; chronic nickel leaching is not unlikely with inevitable metal corrosion.9 The transcatheter patch (TP) ASD correction could theoretically improve on both the surgical morbidity and the disk-device–related problems of ASD occlusion.
METHODS
Transcatheter patch: Transcatheter patches were tailored from polyurethane foam (Foamex-EddystonePenn) and were supported by custom made double or single balloon catheters (NuMed Inc., Hopkinton, New York). A sleeve-type patch was constructed to From the Athenian Institute of Pediatric Cardiology and the Department of Clinical Therapeutics, University of Athens, Athens, Greece; The Military Hospital, Mexico City, Mexico; the Bakulev Institute, Moscow, Russia; and the Cardiology Institute, Tomsk, Russia. Manuscript received November 8, 2001; revised manuscript received and accepted January 18, 2002. Address for reprints: Eleftaherios B. Sideris, MD, Pediatric Cardiology, 1600 Coulter #200, Amarillo, Texas, 79106. E-mail: [email protected].
1082
©2002 by Excerpta Medica, Inc. All rights reserved. The American Journal of Cardiology Vol. 89 May 1, 2002
METHODS The procedures were performed after informed consents were obtained from all patients according to the regulations of each participating institution. Twenty patients underwent successful implantation of a transcatheter patch for ASD occlusion; in 2 additional patients, the balloon/patch was not permanently implanted but was retrieved percutaneously for various reasons. Eighteen of the 20 patients were unsuitable for disk-device occlusion because of either a deficient rim/and or ASD size too large for the septal size. The septal rim was assessed by transesophageal echocardiography in the anterior, superior, and inferior dimensions; we defined the septal rim as deficient if it was ⬍5 mm in any of the measured dimensions. There were 9 defects with deficient anterior rims, 3 defects with deficient superior rims, and 6 defects with deficient inferior rims. Two young patients had defects too large for their atrial septal size to receive the appropriate size of disk device. Two patients were unsuitable for disk-device occlusion, 1 with multiple septal fenestrations. All pa0002-9149/02/$–see front matter PII S0002-9149(02)02280-4
FIGURE 1. A, transcatheter patch (sleeve type) with a double-balloon catheter: The patch (P) is mounted on the distal balloon (DB) of the double-balloon catheter. A nylon thread (ny) is attached to the patch. B, diagram of a double-balloon sleeve patch occlusion (1) and patch release (2). Occlusion involved inflation of the distal balloon/patch in the left atrium first, opposite the defect, and inflation of the proximal balloon. Release involved deflation of the distal and proximal balloons, removal of the balloon catheter, and release of the patch after pulling the double nylon thread as a single strand. PB ⴝ proximal balloon.
FIGURE 2. Left atrial histologic examination of a piglet 48 hours after implantation: Fibrin (F) and inflammatory cells are responsible for attachment of the polyurethane (POL) to the septum (SEP).
tients had significant left-to-right shunts with Qp:Qs 1.5 to 4.0 (median 2.5); 3 patients also had pulmonary hypertension, with systolic pulmonary artery pressure 40 to 55 mm Hg. The patient age ranged from 7 to 65 years (median 37), and the defect size, from 13 to 34 mm (median 26). Patient weight varied between 22 and 90 kg (median 52). All defects with the exception of 1 with multiple fenestrations were single. They were repaired using transcatheter patches supported by double balloons in 18 cases and single distal balloons with proximal floppy disks in 2 cases. Large patches delivered through 12Fr to 13Fr sheaths were used in 18 cases. Small patches delivered through 10Fr sheaths were used for the remaining cases (small balloon/patches can be used for defects up to 15 mm and large ones for all other sizes). The method can be summarized in the following steps: 1. A multipurpose catheter is crossed over the defect and is placed in the left upper pulmonary vein; the catheter is exchanged with an 0.25-inch extra-stiff exchange wire. 2. A large balloon catheter (Meditech, Watertown, Massachusetts, or NuMed) is placed over the wire; balloon sizing, as well as balloon test occlusion of the defect, is performed. Balloon occlusion is performed
under blood pressure/heart rate monitoring and under transesophageal echocardiography; a good candidate for patch occlusion is the patient who has full occlusion of the defect without impairment of pulmonary venous return or the mitral inflow. 3. A sheath of an appropriate length is selected (it should be long enough to reach the left atrium. 4. The patch is provided preloaded in a 10-cm bypass sheath that is the same size as the introducing sheath. It is positioned over the exchange wire through the hemostat valve of the long sheath and is flushed thoroughly; it is released at the level of the inferior vena cava. Subsequently the patch is advanced over the wire in the left atrium. Heparin (100 U/kg or no more than 5,000 U) is administered. Antibiotics (cephalosporins) are given prophylactically for 36 hours. 5. The distal balloon/patch is inflated with dilute contrast at a diameter 2 mm larger than the occluding diameter of the defect. The catheter with the inflated balloon/patch is pulled over the wire to the atrial septum where the defect is occluded. Transesophageal echocardiography and fluoroscopy are required; full occlusion needs to be demonstrated. 6. The proximal balloon is inflated in the right atrium with dilute contrast, at the same diameter as the distal balloon. The wire is extracted. 7. Both the end of the long sheath and the balloon catheter are immobilized by suture and tape outside the groin. The patient is moved to his/her room (or the intensive care unit) with monitoring. The patient is allowed to move in bed but not ambulate. 8. Careful transthoracic echocardiography is required in 24 hours. The diameters of the supporting balloons are verified; the patch should be immobile on the septum. 9. Patch release is done under echocardiography 48 hours after implantation. The groin area with the catheter and sheath endings is cleaned thoroughly with Betadine. The distal balloon is deflated first, followed by the proximal balloon; the entire balloon catheter is then withdrawn. With the tip of the sheath against the patch, the double nylon tie attached to the patch is withdrawn as a single strand releasing the patch.
CONGENITAL HEART DISEASE/TRANSCATHETER PATCH CORRECTION OF ASDs
1083
FIGURE 3. A, 34-mm secundum ASD with deficient inferior rim (
The patch is radiopaque, echogenic, and retractable in the introducing sheath until release.
RESULTS Twenty-two patients were taken to the catheterization laboratory with the intention to treat. Twenty of them had TPs permanently implanted. Two balloons gradually lost their volumes with significant residual shunts upon release (48 hours). Five patients had trivial residual shunts. The balloon patch was detected to be away from the septum by echocardiography at 24 hours in 1 patient. It was pulled to the septum from the groin and was immobilized again, with an excellent result after release (48 hours). All patients with implants were doing well up to 24 months after implantation. One patient with a significant residual shunt received a second patch 6 months after the first implantation, with full occlusion of the defect. On echocardiography, the transcatheter patches were seen to be progressively flatter and practically indistinguishable from the rest of the septum. Most trivial residual shunts did not disappear on follow-up. 1084 THE AMERICAN JOURNAL OF CARDIOLOGY姞
VOL. 89
DISCUSSION Transcatheter occlusion of ASD by disk devices can be an effective outpatient procedure for some secundum ASDs.4,5 However, all disk devices are made with a metal skeleton frame with many acute and possibly long-term complications.10 The described method of transcatheter patch placement could avoid some of the problems of surgery and ASD device repair, because it does not require thoracotomy or sutures for its placement and there is no permanent metal implantation. Ideal TP material should be thin and porous for fast endothelialization. The polyurethane foam fulfilled the above criteria, requiring only 48 hours of temporary support in experimental studies.11 Fibrin and inflammatory cells were shown to be responsible for early septal attachment (Figure 2). The tailoring of the patch can take many desired shapes, including the shape used in this study. Retrievability of the patch during introduction and before withdrawal of the supportive catheters is possible and very important for the safety of the procedure because it was seen in the 2 MAY 1, 2002
FIGURE 4. A, 26-mm ASD secundum with deficient anterior rim (ant) in a 42-year-old patient, by transesophageal echocardiography (longitudinal view). B, transcatheter patch (p) is released 48 hours after implantation; the patch is not only attached to the rim of the defect, but is also attached at the right and left atrial sides (same atrial orientation). C, 1 year after implantation the patch has flattened further and can hardly be distinguished from the rest of the septum; the full occlusion is maintained. Abbreviations as in Figure 3.
abandoned cases; the addition of the radiopaque thread in the construction of the patch helps both optimal position and possible retrieval. The supportive catheter could have several designs, including balloon and floppy wire(s) or double balloon. Theoretically, the double-balloon support could be more secure, particularly for large defects. The possible advantages of the transcatheter patch over the disk devices can be summarized as follows: (1) lack of wire-related problems; (2) increased spectrum of application (less rim requirement); and (3) increased safety features. The TP is a balloon-delivered device with similar advantages to the detachable balloon devices12,13 but with improved safety features.11 The safety features include: (1) no embolization because of intracardiac and outside body support (the operator has total control until the patch is attached to the atrial septum); (2) avoidance of the long sheath air entrapment and air embolization in the coronary arteries (the patch is
delivered in the left atrium over a wire); and (3) a readily retractable and retrievable TP through the introducing sheath. Test occlusion is of paramount importance in predicting the TP result. It should cause full occlusion without impairment of mitral or pulmonary vein flow and no decrease in cardiac output. In situations in which no full occlusion can be achieved during test occlusion, another device with more overlapping should be chosen; the use of multiple TPs is also possible. The importance of full test occlusion before TP placement can also be supported from our early follow-up observations in patients with trivial, small residual shunts. These shunts do not appear to disappear with time, in contrast to disk devices with significant overlapping (Figure 3). A positive follow-up observation was the remodeling of the ASD area with progressive flattening of the patch; the patch area could hardly be distinguished from the rest of the septum (Figure 4). Premature leakage of supportive
CONGENITAL HEART DISEASE/TRANSCATHETER PATCH CORRECTION OF ASDs
1085
balloons in 2 patients was the only device-related problem noticed; although the dilute contrast leakage was not dangerous for patients, it resulted in suboptimal occlusions. Construction of more durable balloons is obviously important. The importance of 24-hour echocardiographic follow-up was demonstrated in 1 patient whose distal balloon was seen away from the septum; it was repositioned and further immobilized from outside, with an excellent result after release. The need for 48-hour hospitalization is an obvious disadvantage of the method. However, it was well tolerated by patients, even the younger patients. No anticoagulation was needed after implantation except for acetylsalicylic acid; the continuous use of anticoagulation is contraindicated because it interferes with the fibrin formation and attachment of the patch to the septum. The introduction area should be covered carefully and antibiotics should be given to prevent infection. Acknowledgment: We would like to thank Chrysoula E. Sideris, RN, for her continuous and dedicated assistance in the animal laboratory, Professor S. Stamatelopoulos, Chairman of the Department of Clinical Therapeutics University of Athens, for his advice and guidance, Professor Bagrat Alekyan of the Bakulev Institute in Moscow for his support and trust in the method, Professor Shipulin of the Department of Cardiovascular Surgery, Tomsk, Russia, for his support, Victor Varvarenko, MD, of the Tomsk Cardiovascular
1086 THE AMERICAN JOURNAL OF CARDIOLOGY姞
VOL. 89
Institute for his assistance, and M. Somarriba, MD, of the Military Hospital, Mexico City, Mexico. 1. King T, Mills N. Nonoperative closure of atrial septal defects. Surgery 1974;75:383–386. 2. Rashkind W, Cuaso C. Transcatheter treatment of congenital heart disease. Circulation 1983;67:711–716. 3. Sideris E, Sideris S, Thanopoulos B, Ehly R, Fowlkes J. Transvenous atrial septal defect occlusion by the “buttoned” device. Am J Cardiol 1990;123:191– 200. 4. Rao PS, Sideris E, Hausdorf G, Rey C, Lloyd T, Beekman R, Worms AM, Bourlon F, Onorato E, Khalilulllah M, Haddad J. International experience with secundum atrial septal defect occlusion by the buttoned device. Am Heart J 1994;128:1022–1035. 5. Prieto LR, Foreman CK, Cheatham JP, Latson LA. Intermediate -term outcome of transcatheter secundum atrial septal defect closure, using the Bard Clamshell septal occluder. Am J Cardiol 1996;78:1310 –1313. 6. Sievert H, Babic M, Ensslen R. Transcatheter closure of large atrial septal defects with the Babic system. Cathet Cardiovasc Diagn 1995;36:232–240. 7. Sunderman FW. A review of the metabolism and toxicology of Nickel. Ann Clin Lab Sci 1977;7:377–398. 8. Ries M, Kampmann C, Meyer J. Nickel release in patients with atrial septal defects after the implantation of the Amplantzer septal occluder (abstr). Circulation 2000;102(suppl II):II–767. 9. Guidoin R, Marois V, Douville Y. First generation aortic endografts: analysis of explanted Stentor devices from the Eurostar Registry. J Endovasc Ther 2000;7:105–122. 10. Agarwal S, Ghosh P, Mittal P. Failure of devices used for closure of atrial septal defects, mechanisms and management. J Thorac Cardiovasc Surg 1996; 112:226 –229. 11. Sideris E, Toumanides S, Alekyan B, Varvarenko V, Stamatelopoulos S, Moulopoulos S. Transcatheter patch correction of atrial septal defects: experimental validation and early clinical experience (abstr). Circulation 2000; 102(suppl II):II–588. 12. Sideris E, Kaneva A , Sideris C, Moulopoulos S. Transcatheter atrial septal defect occlusion in piglets by balloon detachable devices. Cathet Cardiovasc Intervent 2000;51:529 –534. 13. Sideris EB, Chiang CW, Zhang JC, Wang WS. Transcatheter correction of heart defects by detachable balloon buttoned devices: a feasibility study (abstr). J Am Coll Cardiol 1999;23:528A.
MAY 1, 2002