- Email: [email protected]
Prolonged Air Leak After Lung Resection and Emphysema
Ann Thorac Surg 2017;104:718–26
CORRESPONDENCE
723
Fig 1. Repair of large posterior mitral leaflet prolapse. (A) The repair is performed by tightening the neochordae, resulting in no anterior shift of the large leaflet. (B) In patients with narrow posterior head of the papillary muscle, neochordae for the posterior leaflet prolapse are placed in the base of the thick anterior head of the papillary muscle.
2. Manabe S, Kasegawa H, Fukui T, Tabata M, Shimokawa T, Takanashi S. Morphological analysis of systolic anterior motion after mitral valve repair. Interact Cardiovasc Thorac Surg 2012;15:235–9.
Reply To the Editor: I very much appreciate the thoughtful comments from Dr Kim and colleagues [1] regarding our article [2]. As they mentioned, the location and direction of the neochordae are important in our technique. We always fix the neochord to the base of papillary muscle instead of the fibrous tip because the papillary muscle tip is too close to the large leaflet, and there is no room for shortening the neochord to the appropriate length. In addition, we often fix the neochord for the posterior leaflet on the posterior side of the anterior head of papillary muscle when the posterior head is small. Minoru Tabata, MD, MPH Department of Cardiovascular Surgery Tokyo Bay Urayasu Ichikawa Medical Center 3-4-32 Todaijima, Urayasu-shi, Chiba 279-0001, Japan email: [email protected]
References Jong Hun Kim, MD Jong Bum Choi, MD Ja Hong Kuh, MD Department of Thoracic and Cardiovascular Surgery Chonbuk National University Medical School 20 Geonji-Ro, Deokjin-Gu, Jeonju, Chonbuk, 561-712 Republic of Korea email: [email protected]
References 1. Tabata M, Nakatsuka D, Nishida H, Takanashi S, Hiraiwa N, Kawano Y. A simple nonresectional technique for degenerative mitral regurgitation with a very large posterior leaflet: chordal foldoplasty. Ann Thorac Surg 2016;101:e179–81. Ó 2017 by The Society of Thoracic Surgeons Published by Elsevier Inc.
1. Kim JH, Choi JB, Kuh JH. Nonresectional technique for large posterior leaflet prolapse causing mitral regurgitation (letter). Ann Thorac Surg 2017;104:722–3. 2. Tabata M, Nakatsuka D, Nishida H, Takanashi S, Hiraiwa N, Kawano Y. A simple nonresectional technique for degenerative mitral regurgitation with a very large posterior leaflet: chordal foldoplasty. Ann Thorac Surg 2016;101:e179–81.
Prolonged Air Leak After Lung Resection and Emphysema To the Editor: We read with great interest the study by Gilbert and colleagues [1] on identifying patients at higher risk of prolonged air leak 0003-4975/$36.00
MISCELLANEOUS
the prolapsed posterior leaflet, it is important to place expanded polytetrafluoroethylene neochordae on both the prolapsed leaflet and papillary muscles. The advantage of the authors’ repair technique is that it avoids systolic anterior motion that may occur by anterior shift of the coaptation point [2]. In most cases of posterior leaflet prolapse, the prolapse is segmental but not wide. In addition, systolic anterior motion can occur only when the edge of the large posterior leaflet is adjusted to that of the anterior leaflet at the same level to achieve coaptation. The leaflet portion 1.5 cm away from the annulus can be adjusted to the leaflet coaptation level by tightening the neochordae that hold the free edge of the large prolapsed leaflet during saline tests, so the remnant tissue of the large leaflet is located below the real coaptation and closer to the papillary muscle (Fig 1). As a result, the anterior (remnant) portion of the large leaflet becomes the upper part of the neochordae. The repaired posterior leaflet does not cause systolic anterior motion, and the leaflet suture knots are placed below the coaptation. In cases of the posterior leaflet prolapse, the affiliated posterior papillary muscle head is frequently too narrow and weak to hold the neochordae sutures. The neochordae sutures should be fixed to the thick base of the anterior papillary muscle head as a mattress suture with a pledget (Fig 1) or to the groove between the anterior and posterior papillary muscle heads. The location and direction of the neochordae are important for coaptation and smooth motion of the posterior leaflet.
724
CORRESPONDENCE
after lung resection (PAAL). Male sex, smoking history, body mass index less than or equal to 25 kg/m2, Medical Research Council dyspnea score greater than 1, and diffusing capacity of the lungs for carbon monoxide (DLCO) less than 80% showed an association with the occurrence of PAAL. All these factors, especially a low DLCO, are associated with the emphysemaphenotype of chronic obstructive pulmonary disease. Interestingly, in previous studies computed tomography (CT) quantification of emphysema was found to be one of the best predictors of PAAL [2, 3]. With this letter, we want to expand on the discussion on a possible physiologic basis of the association between emphysema and the risk for PAAL. In emphysema, airway resistance can exceed collateral airflow resistance, causing air to flow preferentially through collateral pathways [4, 5]. Collateral ventilation can connect airspaces of an entire lung when incomplete fissures are present [5]. Thus, in the setting of pleuroparenchymal tears of an emphysematous lung, transpleural airflow out through the tear can be a pathway of lower resistance (mediated with collateral ventilation) than expiratory airflow through the (chronically obstructed) airways [4, 5]. We previously described complete transpleural exhalation in patients with severe emphysema, when the pleura or parenchyma is punctured inadvertently during dissection of the lung from the chest wall [4, 5]. In addition to emphysema as an established independent risk factor for PAAL, these physiologic considerations could suggest that incomplete fissures are additional or synergistic risk factors for PAAL. Future studies using quantitative analysis of CT scans to determine emphysema severity and distribution and fissure integrity could provide important novel information to allow enhanced risk stratification to identify patients at risk for PAAL.
MISCELLANEOUS
Michael Eberlein, MD, PhD Division of Pulmonary Critical Care and Occupational Medicine University of Iowa 200 Hawkins Dr, C-33-GH Iowa City, IA 52242 email: [email protected] Kalpaj R. Parekh, MD John Keech, MD Division of Thoracic and Cardiac Surgery University of Iowa Iowa City, Iowa Bassam Redwan, MD Servet Bolukbas, MD, PhD Department of Thoracic Surgery University Hospital Wuppertal University Witten/Herdecke Wuppertal, Germany
References 1. Gilbert S, Maghera S, Seely AJ, et al. Identifying patients at higher risk of prolonged air leak after lung resection. Ann Thorac Surg 2016;102:1674–9. 2. Petrella F, Rizzo S, Radice D, et al. Predicting prolonged air leak after standard pulmonary lobectomy: computed tomography assessment and risk factors stratification. Surgeon 2011 Apr;9(2):72–7. 3. Liang S, Ivanovic J, Gilbert S, et al. Quantifying the incidence and impact of postoperative prolonged alveolar air leak after Ó 2017 by The Society of Thoracic Surgeons Published by Elsevier Inc.
Ann Thorac Surg 2017;104:718–26
pulmonary resection. J Thorac Cardiovasc Surg 2013 Apr;145(4):948–54. 4. Chahla M, Larson CD, Parekh KR, et al. Transpleural Ventilation via Spiracles in Severe Emphysema Increases Alveolar Ventilation. Chest 2016;149:e161–7. 5. Khauli S, Bolukbas S, Reed RM, Eberlein M. Interlobar collateral ventilation in severe emphysema. Thorax 2016.
Reply To the Editor: First, we would like to thank Dr Eberlein and colleagues [1] for enriching our contribution [2] with thoughtful, evidence-based comments focusing on other potential strategies to identify patients who may be at increased risk for a prolonged air leak after lung resection. Despite meticulous care and attention to detail in the handling of tissues during surgery, it seems unlikely that the incidence of prolonged air leaks will be further minimized unless we develop new ways to mitigate this problem effectively. Clinical trials of new approaches to decrease air leaks should ideally be focused on high-risk patients so as to save time, resources, and money. Ideally, high-risk patients should be identified preoperatively using widely available clinical data. In collaboration with others, we have created a new air leak score based on the most recent literature available to date. We hope that the international community of chest physicians and surgeons will be willing to join efforts in a multiinstitutional prospective validation of the score. Sebastien Gilbert, MD Sonam Maghera, BS Andrew J. Seely, MD, PhD Donna E. Maziak, MDCM, MS Farid M. Shamji, MD Sudhir R. Sundaresan, MD Patrick J. Villeneuve, MD, PhD Division of Thoracic Surgery University of Ottawa The Ottawa Hospital General Campus, Ste 6363 501 Smyth Rd Ottawa, Ontario K1H 8L6, Canada email: [email protected]
References 1. Eberlein M, Parekh KR, Keech J, Redwan B, Bolukbas S. Prolonged air leak after lung resection and emphysema (letter). Ann Thorac Surg 2017;104:723–4. 2. Gilbert S, Maghera S, Seely AJ, et al. Identifying patients at higher risk of prolonged air leak after lung resection. Ann Thorac Surg 2016;102:1674–9.
Venoarterial Extracorporeal Membrane Oxygenation: Lower Speed, and You May Be Faster To the Editor: The mortality of patients with cardiogenic shock receiving venoarterial extracorporeal membrane oxygenation (VA-ECMO) is still very high. Albeit complex, this suggests that current strategies of mechanical support leave room for improvement. We read with great interest the study by Unai and colleagues [1]. Of 98 patients with cardiogenic shock who were receiving VA-ECMO, 22% had spontaneous echo contrast (SEC), more 0003-4975/$36.00
CORRESPONDENCE
723
Fig 1. Repair of large posterior mitral leaflet prolapse. (A) The repair is performed by tightening the neochordae, resulting in no anterior shift of the large leaflet. (B) In patients with narrow posterior head of the papillary muscle, neochordae for the posterior leaflet prolapse are placed in the base of the thick anterior head of the papillary muscle.
2. Manabe S, Kasegawa H, Fukui T, Tabata M, Shimokawa T, Takanashi S. Morphological analysis of systolic anterior motion after mitral valve repair. Interact Cardiovasc Thorac Surg 2012;15:235–9.
Reply To the Editor: I very much appreciate the thoughtful comments from Dr Kim and colleagues [1] regarding our article [2]. As they mentioned, the location and direction of the neochordae are important in our technique. We always fix the neochord to the base of papillary muscle instead of the fibrous tip because the papillary muscle tip is too close to the large leaflet, and there is no room for shortening the neochord to the appropriate length. In addition, we often fix the neochord for the posterior leaflet on the posterior side of the anterior head of papillary muscle when the posterior head is small. Minoru Tabata, MD, MPH Department of Cardiovascular Surgery Tokyo Bay Urayasu Ichikawa Medical Center 3-4-32 Todaijima, Urayasu-shi, Chiba 279-0001, Japan email: [email protected]
References Jong Hun Kim, MD Jong Bum Choi, MD Ja Hong Kuh, MD Department of Thoracic and Cardiovascular Surgery Chonbuk National University Medical School 20 Geonji-Ro, Deokjin-Gu, Jeonju, Chonbuk, 561-712 Republic of Korea email: [email protected]
References 1. Tabata M, Nakatsuka D, Nishida H, Takanashi S, Hiraiwa N, Kawano Y. A simple nonresectional technique for degenerative mitral regurgitation with a very large posterior leaflet: chordal foldoplasty. Ann Thorac Surg 2016;101:e179–81. Ó 2017 by The Society of Thoracic Surgeons Published by Elsevier Inc.
1. Kim JH, Choi JB, Kuh JH. Nonresectional technique for large posterior leaflet prolapse causing mitral regurgitation (letter). Ann Thorac Surg 2017;104:722–3. 2. Tabata M, Nakatsuka D, Nishida H, Takanashi S, Hiraiwa N, Kawano Y. A simple nonresectional technique for degenerative mitral regurgitation with a very large posterior leaflet: chordal foldoplasty. Ann Thorac Surg 2016;101:e179–81.
Prolonged Air Leak After Lung Resection and Emphysema To the Editor: We read with great interest the study by Gilbert and colleagues [1] on identifying patients at higher risk of prolonged air leak 0003-4975/$36.00
MISCELLANEOUS
the prolapsed posterior leaflet, it is important to place expanded polytetrafluoroethylene neochordae on both the prolapsed leaflet and papillary muscles. The advantage of the authors’ repair technique is that it avoids systolic anterior motion that may occur by anterior shift of the coaptation point [2]. In most cases of posterior leaflet prolapse, the prolapse is segmental but not wide. In addition, systolic anterior motion can occur only when the edge of the large posterior leaflet is adjusted to that of the anterior leaflet at the same level to achieve coaptation. The leaflet portion 1.5 cm away from the annulus can be adjusted to the leaflet coaptation level by tightening the neochordae that hold the free edge of the large prolapsed leaflet during saline tests, so the remnant tissue of the large leaflet is located below the real coaptation and closer to the papillary muscle (Fig 1). As a result, the anterior (remnant) portion of the large leaflet becomes the upper part of the neochordae. The repaired posterior leaflet does not cause systolic anterior motion, and the leaflet suture knots are placed below the coaptation. In cases of the posterior leaflet prolapse, the affiliated posterior papillary muscle head is frequently too narrow and weak to hold the neochordae sutures. The neochordae sutures should be fixed to the thick base of the anterior papillary muscle head as a mattress suture with a pledget (Fig 1) or to the groove between the anterior and posterior papillary muscle heads. The location and direction of the neochordae are important for coaptation and smooth motion of the posterior leaflet.
724
CORRESPONDENCE
after lung resection (PAAL). Male sex, smoking history, body mass index less than or equal to 25 kg/m2, Medical Research Council dyspnea score greater than 1, and diffusing capacity of the lungs for carbon monoxide (DLCO) less than 80% showed an association with the occurrence of PAAL. All these factors, especially a low DLCO, are associated with the emphysemaphenotype of chronic obstructive pulmonary disease. Interestingly, in previous studies computed tomography (CT) quantification of emphysema was found to be one of the best predictors of PAAL [2, 3]. With this letter, we want to expand on the discussion on a possible physiologic basis of the association between emphysema and the risk for PAAL. In emphysema, airway resistance can exceed collateral airflow resistance, causing air to flow preferentially through collateral pathways [4, 5]. Collateral ventilation can connect airspaces of an entire lung when incomplete fissures are present [5]. Thus, in the setting of pleuroparenchymal tears of an emphysematous lung, transpleural airflow out through the tear can be a pathway of lower resistance (mediated with collateral ventilation) than expiratory airflow through the (chronically obstructed) airways [4, 5]. We previously described complete transpleural exhalation in patients with severe emphysema, when the pleura or parenchyma is punctured inadvertently during dissection of the lung from the chest wall [4, 5]. In addition to emphysema as an established independent risk factor for PAAL, these physiologic considerations could suggest that incomplete fissures are additional or synergistic risk factors for PAAL. Future studies using quantitative analysis of CT scans to determine emphysema severity and distribution and fissure integrity could provide important novel information to allow enhanced risk stratification to identify patients at risk for PAAL.
MISCELLANEOUS
Michael Eberlein, MD, PhD Division of Pulmonary Critical Care and Occupational Medicine University of Iowa 200 Hawkins Dr, C-33-GH Iowa City, IA 52242 email: [email protected] Kalpaj R. Parekh, MD John Keech, MD Division of Thoracic and Cardiac Surgery University of Iowa Iowa City, Iowa Bassam Redwan, MD Servet Bolukbas, MD, PhD Department of Thoracic Surgery University Hospital Wuppertal University Witten/Herdecke Wuppertal, Germany
References 1. Gilbert S, Maghera S, Seely AJ, et al. Identifying patients at higher risk of prolonged air leak after lung resection. Ann Thorac Surg 2016;102:1674–9. 2. Petrella F, Rizzo S, Radice D, et al. Predicting prolonged air leak after standard pulmonary lobectomy: computed tomography assessment and risk factors stratification. Surgeon 2011 Apr;9(2):72–7. 3. Liang S, Ivanovic J, Gilbert S, et al. Quantifying the incidence and impact of postoperative prolonged alveolar air leak after Ó 2017 by The Society of Thoracic Surgeons Published by Elsevier Inc.
Ann Thorac Surg 2017;104:718–26
pulmonary resection. J Thorac Cardiovasc Surg 2013 Apr;145(4):948–54. 4. Chahla M, Larson CD, Parekh KR, et al. Transpleural Ventilation via Spiracles in Severe Emphysema Increases Alveolar Ventilation. Chest 2016;149:e161–7. 5. Khauli S, Bolukbas S, Reed RM, Eberlein M. Interlobar collateral ventilation in severe emphysema. Thorax 2016.
Reply To the Editor: First, we would like to thank Dr Eberlein and colleagues [1] for enriching our contribution [2] with thoughtful, evidence-based comments focusing on other potential strategies to identify patients who may be at increased risk for a prolonged air leak after lung resection. Despite meticulous care and attention to detail in the handling of tissues during surgery, it seems unlikely that the incidence of prolonged air leaks will be further minimized unless we develop new ways to mitigate this problem effectively. Clinical trials of new approaches to decrease air leaks should ideally be focused on high-risk patients so as to save time, resources, and money. Ideally, high-risk patients should be identified preoperatively using widely available clinical data. In collaboration with others, we have created a new air leak score based on the most recent literature available to date. We hope that the international community of chest physicians and surgeons will be willing to join efforts in a multiinstitutional prospective validation of the score. Sebastien Gilbert, MD Sonam Maghera, BS Andrew J. Seely, MD, PhD Donna E. Maziak, MDCM, MS Farid M. Shamji, MD Sudhir R. Sundaresan, MD Patrick J. Villeneuve, MD, PhD Division of Thoracic Surgery University of Ottawa The Ottawa Hospital General Campus, Ste 6363 501 Smyth Rd Ottawa, Ontario K1H 8L6, Canada email: [email protected]
References 1. Eberlein M, Parekh KR, Keech J, Redwan B, Bolukbas S. Prolonged air leak after lung resection and emphysema (letter). Ann Thorac Surg 2017;104:723–4. 2. Gilbert S, Maghera S, Seely AJ, et al. Identifying patients at higher risk of prolonged air leak after lung resection. Ann Thorac Surg 2016;102:1674–9.
Venoarterial Extracorporeal Membrane Oxygenation: Lower Speed, and You May Be Faster To the Editor: The mortality of patients with cardiogenic shock receiving venoarterial extracorporeal membrane oxygenation (VA-ECMO) is still very high. Albeit complex, this suggests that current strategies of mechanical support leave room for improvement. We read with great interest the study by Unai and colleagues [1]. Of 98 patients with cardiogenic shock who were receiving VA-ECMO, 22% had spontaneous echo contrast (SEC), more 0003-4975/$36.00