- Email: [email protected]
Beating Heart Cardioscopy: On-Pump or Off-Pump?
Ann Thorac Surg 2008;86:1399 – 403
1. Gaeta R, Lentini S, Monaco F, Tancredi F, Savasta M. Perfusion of the lower part of the body during open aortic arch surgery (letter). Ann Thorac Surg 2008; 86:1400. 2. Panos A, Myers PO, Kalangos A. Novel technique for aortic arch surgery under mild hypothermia. Ann Thorac Surg 2008; 85:347– 8.
Beating Heart Cardioscopy: On-Pump or Off-Pump? To the Editor: I read with great interest the article by Mihaljevic and colleagues [1] on cardioscopy. The authors presented a novel method for obtaining intracardiac visual fields during on-pump beating heart conditions, and they advocate that this method would provide a less invasive percutaneous approach compared with current open heart procedures. Cardioscopic procedures have been performed within small cardiac chambers filled with pulsating body fluids and moving target organs [2]. Because transluminal access to cardiac chambers is limited, designs for (1) vision technique, (2) access, (3) placement of flexible catheters, and (4) stabilization of the visual field and target organ are important for percutaneous intervention [3]. However, Mihaljevic and colleagues’ [1] methods may be incompatible with this strategy because cannulas for cardiopulmonary bypass and perfusion dominate percutaneous access and leave little room for manipulation of a properly-sized cardioscope, transluminal forceps, and catheters. If a cardioscopic procedure is intended to reduce surgical trauma, off-pump beating heart surgery would be preferred [4]. Although the visual field is limited, a balloon-tipped flexible cardioscope assures a clear visual field without blood clouding, obviates blocking percutaneous access, and provides stabilization with flexible angle manipulation and long-term inspection without cardiopulmonary bypass [5]. Combined with the latest color Doppler and three-dimensional ultrasound imaging, which provide sufficient functional and spatial anatomical landmarks, this method allows an alternative approach for off-pump beating heart intracardiac technique. Yoshito Inoue, MD Department of Cardiovascular Surgery 911-1 Takebayashi Saiseikai Utsunomiya Hospital Utsunomiya, Tochigi, 321-0974 Japan e-mail: [email protected]
References 1. Mihaljevic T, Ootaki Y, Robertson JO, et al. Beating heart cardioscopy: a platform for real-time, intracardiac imaging. Ann Thorac Surg 2008; 85:1061– 6. 2. Inoue Y, Yozu R, Ueda T, Mitsumaru A, Kawada S. Transluminal cardioscopic maze-ablation of atrial fibrillation. Circulation 1995; 92(Suppl):I-85. 3. Inoue Y, Yozu R, Mitsumaru A, Ueda T, Kawada S. Videoassisted cardioscopic staple closure for atrial septal defect. Artif Organs 1997; 21:1303–5. 4. Inoue Y, Yozu R, Mitsumaru A, et al. Video assisted thoracoscopic and cardioscopic maze ablation. ASAIO J 1997; 43: 334 –7. 5. Inoue Y, Yozu R, Onoguchi K, Kabei N, Takeuchi S, Kawada S. Cardioscopic guidance of linear lesion creation for radiofrequency ablation. Ann Thorac Surg 2003; 75:1189 –93. © 2008 by The Society of Thoracic Surgeons Published by Elsevier Inc
1401
Reply To the Editor: We thank Dr Inoue [1] for his thoughtful comments on our article [2]. However, we have a completely different view of the subject. Beating heart cardioscopy, as proposed by Inoue [1] uses a balloon-tipped flexible cardioscope. This approach allows very limited visualization of intracardiac anatomy because the instrument needs to be pressed against the structure that needs to be visualized. Use of adjunctive visualization techniques (such as echocardiography) has proved to be very difficult due to poor image quality caused by echogenicity of instrumentation. Therefore, the use of this technology has been limited to the repair of simpler defects and creation of ablation lines for atrial fibrillation [3, 4]. However, the use of such instruments for treatment of valvular heart disease is close to impossible because they distort the valve anatomy and can cause the obstruction of blood flow or severe regurgitation. Although the idea of balloon-tipped cardioscopes is very old, it never established itself in clinical practice due to the previously mentioned limitations. In contrast, our method provides a stable hemodynamic environment and unlimited visualization of the entire intracardiac anatomy, which is the essential prerequisite for successful complex intracardiac interventions [2]. We do not believe that cannulas for extracorporeal circulation limit the use of instruments because they can be designed in such a way that allow simultaneous delivery of instrumentation. In conclusion, we believe that efforts in the development of methods for intracardiac visualization are important. Whether those methods will be used with or without cardiopulmonary bypass will likely depend on the indication for treatment. Tomislav Mihaljevic, MD Department of Thoracic and Cardiovascular Surgery Cleveland Clinic 9500 Euclid Ave Cleveland, OH 44195 e-mail: [email protected]
References 1. Inoue Y. Beating heart cardioscopy: on-pump or off-pump? (letter). Ann Thorac Surg 2008;86:1401. 2. Mihaljevic T, Ootaki Y, Roberson JO, et al. Beating heart cardioscopy: a platform for real-time, intracardiac imaging. Ann Thorac Surg 2008;85:1061– 6. 3. Inoue Y, Yozu R, Mitsumaru A, Ueda T, Kawada S. Videoassisted cardioscopic stable closure for atrial septal defect. Artif Organs 1997;21:1303–5. 4. Inoue Y, Yozu R, Onogurchi K, Kabei N, Takeuchi S, Kawada S. Caridioscopic guidance of linear lesion creation for radiofrequency ablation. Ann Thorac Surg 2003;75:1189 –93.
New Discussion on an Old Subject: Proximal Anastomosis Markers in Coronary Bypass Surgery To the Editor: Olenchock and colleagues [1] revived an important subject on the use of proximal anastomosis markers in coronary bypass surgery. Although late graft patency was not different between marked or nonmarked saphenous vein grafts (SVG), the perioperative myocardial infarction (MI) rate was higher in patients with SVG markers. The article has scientific strengths with its large volume, and prospective and multicenter design. 0003-4975/08/$34.00
MISCELLANEOUS
References
CORRESPONDENCE
1. Gaeta R, Lentini S, Monaco F, Tancredi F, Savasta M. Perfusion of the lower part of the body during open aortic arch surgery (letter). Ann Thorac Surg 2008; 86:1400. 2. Panos A, Myers PO, Kalangos A. Novel technique for aortic arch surgery under mild hypothermia. Ann Thorac Surg 2008; 85:347– 8.
Beating Heart Cardioscopy: On-Pump or Off-Pump? To the Editor: I read with great interest the article by Mihaljevic and colleagues [1] on cardioscopy. The authors presented a novel method for obtaining intracardiac visual fields during on-pump beating heart conditions, and they advocate that this method would provide a less invasive percutaneous approach compared with current open heart procedures. Cardioscopic procedures have been performed within small cardiac chambers filled with pulsating body fluids and moving target organs [2]. Because transluminal access to cardiac chambers is limited, designs for (1) vision technique, (2) access, (3) placement of flexible catheters, and (4) stabilization of the visual field and target organ are important for percutaneous intervention [3]. However, Mihaljevic and colleagues’ [1] methods may be incompatible with this strategy because cannulas for cardiopulmonary bypass and perfusion dominate percutaneous access and leave little room for manipulation of a properly-sized cardioscope, transluminal forceps, and catheters. If a cardioscopic procedure is intended to reduce surgical trauma, off-pump beating heart surgery would be preferred [4]. Although the visual field is limited, a balloon-tipped flexible cardioscope assures a clear visual field without blood clouding, obviates blocking percutaneous access, and provides stabilization with flexible angle manipulation and long-term inspection without cardiopulmonary bypass [5]. Combined with the latest color Doppler and three-dimensional ultrasound imaging, which provide sufficient functional and spatial anatomical landmarks, this method allows an alternative approach for off-pump beating heart intracardiac technique. Yoshito Inoue, MD Department of Cardiovascular Surgery 911-1 Takebayashi Saiseikai Utsunomiya Hospital Utsunomiya, Tochigi, 321-0974 Japan e-mail: [email protected]
References 1. Mihaljevic T, Ootaki Y, Robertson JO, et al. Beating heart cardioscopy: a platform for real-time, intracardiac imaging. Ann Thorac Surg 2008; 85:1061– 6. 2. Inoue Y, Yozu R, Ueda T, Mitsumaru A, Kawada S. Transluminal cardioscopic maze-ablation of atrial fibrillation. Circulation 1995; 92(Suppl):I-85. 3. Inoue Y, Yozu R, Mitsumaru A, Ueda T, Kawada S. Videoassisted cardioscopic staple closure for atrial septal defect. Artif Organs 1997; 21:1303–5. 4. Inoue Y, Yozu R, Mitsumaru A, et al. Video assisted thoracoscopic and cardioscopic maze ablation. ASAIO J 1997; 43: 334 –7. 5. Inoue Y, Yozu R, Onoguchi K, Kabei N, Takeuchi S, Kawada S. Cardioscopic guidance of linear lesion creation for radiofrequency ablation. Ann Thorac Surg 2003; 75:1189 –93. © 2008 by The Society of Thoracic Surgeons Published by Elsevier Inc
1401
Reply To the Editor: We thank Dr Inoue [1] for his thoughtful comments on our article [2]. However, we have a completely different view of the subject. Beating heart cardioscopy, as proposed by Inoue [1] uses a balloon-tipped flexible cardioscope. This approach allows very limited visualization of intracardiac anatomy because the instrument needs to be pressed against the structure that needs to be visualized. Use of adjunctive visualization techniques (such as echocardiography) has proved to be very difficult due to poor image quality caused by echogenicity of instrumentation. Therefore, the use of this technology has been limited to the repair of simpler defects and creation of ablation lines for atrial fibrillation [3, 4]. However, the use of such instruments for treatment of valvular heart disease is close to impossible because they distort the valve anatomy and can cause the obstruction of blood flow or severe regurgitation. Although the idea of balloon-tipped cardioscopes is very old, it never established itself in clinical practice due to the previously mentioned limitations. In contrast, our method provides a stable hemodynamic environment and unlimited visualization of the entire intracardiac anatomy, which is the essential prerequisite for successful complex intracardiac interventions [2]. We do not believe that cannulas for extracorporeal circulation limit the use of instruments because they can be designed in such a way that allow simultaneous delivery of instrumentation. In conclusion, we believe that efforts in the development of methods for intracardiac visualization are important. Whether those methods will be used with or without cardiopulmonary bypass will likely depend on the indication for treatment. Tomislav Mihaljevic, MD Department of Thoracic and Cardiovascular Surgery Cleveland Clinic 9500 Euclid Ave Cleveland, OH 44195 e-mail: [email protected]
References 1. Inoue Y. Beating heart cardioscopy: on-pump or off-pump? (letter). Ann Thorac Surg 2008;86:1401. 2. Mihaljevic T, Ootaki Y, Roberson JO, et al. Beating heart cardioscopy: a platform for real-time, intracardiac imaging. Ann Thorac Surg 2008;85:1061– 6. 3. Inoue Y, Yozu R, Mitsumaru A, Ueda T, Kawada S. Videoassisted cardioscopic stable closure for atrial septal defect. Artif Organs 1997;21:1303–5. 4. Inoue Y, Yozu R, Onogurchi K, Kabei N, Takeuchi S, Kawada S. Caridioscopic guidance of linear lesion creation for radiofrequency ablation. Ann Thorac Surg 2003;75:1189 –93.
New Discussion on an Old Subject: Proximal Anastomosis Markers in Coronary Bypass Surgery To the Editor: Olenchock and colleagues [1] revived an important subject on the use of proximal anastomosis markers in coronary bypass surgery. Although late graft patency was not different between marked or nonmarked saphenous vein grafts (SVG), the perioperative myocardial infarction (MI) rate was higher in patients with SVG markers. The article has scientific strengths with its large volume, and prospective and multicenter design. 0003-4975/08/$34.00
MISCELLANEOUS
References
CORRESPONDENCE