Changing Outcomes of Pulmonary Artery Banding With the Percutaneously Adjustable Pulmonary Artery Band

PEDIATRIC CARDIAC SURGERY:

Changing Outcomes of Pulmonary Artery Banding With the Percutaneously Adjustable Pulmonary Artery Band Sachin Talwar, MCh, Shiv Kumar Choudhary, MCh, Ankit Mathur, MS, Balram Airan, MCh, Rajvir Singh, PhD, Rajnish Juneja, DM, Shyam Sunder Kothari, DM, and Anita Saxena, DM Cardiothoracic Centre and Department of Biostatistics, All India Institute of Medical Sciences, New Delhi, India

Background. Conventional pulmonary artery banding (CPAB) is associated with high morbidity and mortality. We studied the changes in outcome with the use of an adjustable pulmonary artery band (APAB). Methods. Between June 2001 and June 2006, 147 patients underwent PAB: 91 underwent CPAB and 56 underwent APAB. Results. The clinical profile of patients was similar in both groups. Inotropic drugs were used in 91 (100%) patients in the CPAB group and in 12 (21%) in the APAB group (p < 0.001). Early band related reoperation was required in 17 patients in the CPAB group compared with 2 patients in the APAB group (p ⴝ 0.014). There were 21 (23%) early deaths in CPAB group compared with 1 (1.8%) in the APAB group (p < 0.001). There was

no difference in the intensive care unit stay, hospital stay, and final band gradients in the two groups. On a mean follow-up of 22.8 ⴞ 18.6 months (range, 4 to 72 months), there was PA distortion in 6 patients and band-migration in 4 patients in the CPAB group. These were not observed in the APAB group. Conclusions. Similar band gradients were achieved with the use of conventional or adjustable PAB. However, the use of this simple and inexpensive technique of APAB was associated with a significant reduction in the early band-related deaths, need for early multiple reoperations, and early adverse acute events, thus making it a safer alternative to CPAB, more so in unstable patients. (Ann Thorac Surg 2008;85:593– 8) © 2008 by The Society of Thoracic Surgeons

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of APAB systems have been developed, which are technically complex and expensive [12–16]. We have also developed a simple and inexpensive technique of APAB and reported this technique recently [17]. In this report, we discuss our experience with PAB during the 5 years and compare the outcomes obtained with the use of either conventional or adjustable PAB.

ince pulmonary artery banding (PAB) was first performed by Muller and Dammann [1], its indications have gradually diminished due to a gradually increasing trend towards early primary repair of more complex cardiac malformations. However, it is still a useful initial palliation for patients with multiple ventricular septal defects, to reduce the excessive pulmonary blood flow in patients with single ventricle physiology, and for retraining the left ventricle as a part of the rapid two-stage arterial switch operation [2–7]. Conventional PAB (CPAB) has always been associated with high morbidity and mortality and a high reoperation rate, which has not diminished appreciably [8 –11]. This has prompted development of the concept of adjustable PAB (APAB), where the pulmonary blood flow can be controlled to tide over a period of hemodynamic instability in these patients who often do not tolerate a sudden increase in the after load to the ventricle. A wide variety

Accepted for publication July 19, 2007. Address correspondence to Dr Choudhary, Department of Cardiothoracic and Vascular Surgery, All India Institute of Medical Sciences, New Delhi 110029, India; e-mail: [email protected].

© 2008 by The Society of Thoracic Surgeons Published by Elsevier Inc

Patients and Methods Between June 2001 and June 2006, 147 patients underwent PAB at the All India Institute of Medical Sciences, New Delhi, India. Of these, 91 (61.9%) underwent CPAB and 56 (38%) had APAB. Informed consent was obtained from the parents of all patients of the study, and the hospital Ethics Committee approved the surgical procedures and the study. Only patients requiring isolated PAB were included in this study. Exclusion criteria included patients requiring repair of coarctation of aorta, atrial septectomy, and those requiring the addition of a systemic-to-pulmonary artery shunt for retraining the left ventricle in the setting of 0003-4975/08/$34.00 doi:10.1016/j.athoracsur.2007.07.057

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transposition of great arteries and intact ventricular septum with low left ventricular pressures. The demographic features and underlying cardiac diagnosis are listed in Table 1. CARDIOVASCULAR

Surgical Technique Similar anesthesia techniques were used in both groups. Patients in both groups underwent a median sternotomy for PAB. A limited manubriotomy was used in 6 patients in the APAB group. After sternotomy or manubriotomy, the thymus was dissected away but not excised. The pericardium was opened vertically in an inverted T fashion just enough to expose the aorta, main pulmonary artery (MPA), and the patent ductus arteriosus. The aortopulmonary septum was then dissected to separate the MPA from the aorta. The patent ductus arteriosus was dissected and either ligated or clipped. In the CPAB group, the MPA was looped by the subtraction technique and a 5-mm-wide Merselene tape (RS-21.P01 Ethicon, Somerville, NJ) was passed around it. Before passing around the MPA, the Merselene tape was marked for the desired bandwidth calculated using the Trusler formula [18]. A purse string suture was used to place a 23-gauge needle in the distal MPA to monitor the PA pressure. At this stage, the inspired oxygen concentration (Fio2) was set to 50%, and the adequate band length was achieved while monitoring the distal PA pressure, systemic saturation, and the hemodynamics. In patients with noncyanotic, nonmixing lesions, such as a ventricular septal defect, the initial circumference of the band was set at 20 mm ⫹ 1 mm/kg body weight. In patients with single ventricle physiology, it was set at 22 mm ⫹ 1 mm/kg body weight. This was used as the Table 1. Demographic Features and Underlying Cardiac Diagnosis Characteristics

CPAB (n ⫽ 91)

APAB (n ⫽ 56)

p Value

Demographics Median age, mon 4 ⫾ 2.1 (1–168) 3 ⫾ 2.4 (0.5–132) 0.281 (range) Median weight, 4.2 ⫾ 0.4 (2–35) 3.8 ⫾ 0.4 (1.8–21) 0.263 kg (range) Diagnosis Double ventricles 50 31 Multiple VSDs 31 26 AVSD 12 02 DORV-VSD-PAH 7 3 Single ventricle 41 25 TA PAH 19 10 AVSD 4 4 CTGA VSD 7 3 DILV 6 4 SVPAH 5 4 APAB ⫽ adjustable pulmonary artery banding; CPAB ⫽ conventional pulmonary artery banding; DILV ⫽ double inlet left ventricle; DORV ⫽ double-outlet right ventricle; PAH ⫽ pulmonary arterial hypertension; TGA ⫽ transposition of great arteries; VSD ⫽ ventricular septal defect.

Fig 1. The technique of adjustable pulmonary artery banding. The Ethibond (Johnson & Johnson Inc, Somerville, NJ) suture is doubly looped around the pulmonary artery (PA), passed through a polytetrafluoroethylene (PTFE) pledget (T) and a clip (C) is applied to both the threads flush with the pledget. They are then passed through the pericardium, sternum, subcutaneous tissue, and skin, and through another PTFE pledget (TT). Another clip (CC) is applied above the TT before the suture is tied together to form a loop. Subsequent tightening is accomplished by placing additional clips between the outside clip (CC) and the TT. (Reprinted from Choudhary SK, Talwar S, Airan B, Mohapatra R, Juneja R, Kothari SS, et al. A new technique of percutaneously adjustable pulmonary artery banding. J Thorac Cardiovasc Surg 2006;131:621– 4. Copyright 2006, with permission from the American Association for Thoracic Surgery.)

starting point for the banding, and adjustments in band width were made by monitoring the overall hemodynamic status, systemic oxygen saturation, and PA pressures. In general, we attempted to reduce the PA pressures to about one-third of the systemic arterial blood pressure. Once the PAB was considered to be optimal, the two ends of the Merselene tape were fixed using 2 to 3 clips (LT 200 Ethicon), and the band was transfixed to the adventitia of the MPA using 5-0 polypropylene suture to prevent migration. We described the technique of APAB recently in detail [17]. This is illustrated in Figure 1. In brief, in this technique, the MPA was looped with a No. 2 Ethibond

(Johnson & Johnson Inc, Somerville, NJ) suture after passing a right-angle forceps between the aorta and the MPA. This right-angle forceps was again passed and the suture end was grasped again, so that the MPA was doubly looped. The two ends of this suture were passed through a 0.5 ⫻ 0.5-cm polytetrafluoroethylene (PTFE) pledget, which was anchored to the adventitia of the MPA using interrupted 5-0 polypropylene suture. Both arms of the suture were clipped together with a Liga clip (LT 200; Ethicon Endosurgery Inc, Cincinnati, OH) just on the pledget. These sutures were brought out through the pericardium and the lateral edge of the sternum and then through subcutaneous tissue and skin. After sternal closure, the two ends of the suture were passed through another 1 ⫻ 2-cm PTFE pledget, and these were clipped together with a big Ligaclip (LT 400, Ethicon Endosurgery). The ends of the suture were then tied to form a loop. After routine wound closure in both the groups, the patients were shifted to the intensive care unit (ICU). In patients in the CPAB group, dopamine was routinely started in the operating room at a dose of 5 ␮g/kg/min. Patients in the CPAB group were kept on ventilatory support until satisfactory hemodynamics was obtained with acceptable gradients, and only then were the mechanical ventilatory support and inotropic agents gradually withdrawn. Baseline echocardiograms were obtained within 6 hours of arrival in the ICU and were repeated at 24-hour intervals or more frequently if indicated. In the APAB group, the tightening of the band was started in the ICU whenever possible after the patient was extubated and breathing room air. If heart failure was believed to preclude early extubation, the band was tightened just enough to achieve extubation and the final band tightening was done only after the patient was extubated and breathing room air. The treating surgeon performed band tightening by placing additional big clips (LT 400, Ethicon Endosurgery) outside between the PTFE pledget and the previous clip under pulse oximetry guidance while the cardiologist performed transthoracic echocardiography. Typically, the tightening was performed in three to six sessions during a period of 4 to 7 days, and no more than a 30 mm Hg gradient was added at a time. Most patients required four sessions to achieve an adequate gradient. In two ventricle candidates, a gradient of approximately 60 mm Hg across the band was the target with a minimally acceptable systemic saturation of 85%. In univentricular candidates, maximal band tightening was achieved taking care that the systemic saturation always exceeded 75% and there was no hemodynamic compromise. If systemic desaturation and bradycardia occurred during band tightening, the last clip was removed and the two threads were allowed to retract inside. All patients in the APAB group received antibiotic prophylaxis while the band was outside. Once satisfactory gradients were achieved, the band was internalized by making a small opening in the subcutaneous plane and clipping the two threads together. The sutures above this were cut, and the wound

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was closed. The patients were discharged only after internalization and no subsequent adjustments were made. After discharge from the hospital, the patients were seen in the outpatient clinic after 1 month and then once every 3 months. At each visit, they were assessed clinically, their peripheral saturation was measured, and echocardiography was performed for band gradients, for estimating pulmonary artery pressures, and to assess the ventricular function. Before definitive surgery, all the patients underwent complete cardiac catheterization and angiography for estimating the PA pressure and to rule out band migration or PA distortion, or both. Their last follow-up visit between July and September 2006 was recorded and was used for reporting the results.

Statistical Analysis Statistical analysis was done with SPSS 11.5 software (SPSS, Chicago IL). Descriptive statistics, including mean, median, standard deviation, and frequency, were calculated for each variable. To assess the differences between two groups, the Student t test was used for continuous variables and the ␹2 test was used for categoric variables. Stepwise logistic regression analysis was performed to assess the effect of each variable on the early mortality and band-related acute events. For the purposes of assessing early outcome and morbidity, a band-related adverse event was defined as any episode of sudden cardiac decompensation requiring reinstitution of mechanical ventilatory support or increasing inotrope requirement, or both, ventricular arrhythmias necessitating resuscitation, sudden unexplained death, or any event requiring reoperation for loosening or tightening of the band. A value of p ⬍ 0.05 was considered statistically significant. A band-related death was defined as death occurring within 1 month or in the period of the same hospitalization after low cardiac output or ventricular arrhythmias, or occurring after reoperation or a death of unknown etiology. To further assess the influence of diagnosis on Table 2. Outcomes of Patients Undergoing Conventional and Adjustable Pulmonary Artery Banding Variablea

CPAB (n ⫽ 91)

APAB (n ⫽ 56)

Mechanical ventilation, h 14 ⫾ 19.2 14 ⫾ 29.9 Inotrope requirement 91 (100) 12 (21) Early band-related re-op 17 (18.7) 2 (3.6) Acute events 37 (41) 14 (25) Band-related deaths 21 (23) 1 (1.8) Intensive care unit stay, h 48 ⫾ 29.4 48 ⫾ 28.7 Hospital stay, d 11.9 ⫾ 1.6 15.4 ⫾ 1.3 Final band gradient, 60 ⫾ 2.4 56 ⫾ 2.4 mm Hg

Difference (p Value) 0.88 ⬍ 0.001 0.014 0.038 ⬍ 0.001 0.41 0.12 0.9

a Continuous data are presented with the standard deviation: categoric data are presented as number (%).

APAB ⫽ adjustable pulmonary artery banding; pulmonary artery banding.

CPAB ⫽ conventional

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mortality, the patients were broadly divided into two groups. The first group included patients with a future two-ventricle repair and the second group consisted of patients with univentricular physiology. Risk factors for early mortality were analyzed using multivariate analysis. The influences of age, weight, and diagnosis, as well as the type of band (APAB or CPAB) on the mortality rate was analyzed.

Results The clinical profile of patients undergoing APAB or CPAB is listed in Table 1, and Table 2 presents their outcomes. In the APAB group, satisfactory band gradients were achieved during a period of 10.5 ⫾ 0.9 days, and the band was subsequently internalized. There were 22 early deaths: 21 (23%) in the CPAB group and one (1.8%) in the APAB group. Of the 21 early deaths in CPAB group, seven were due to sudden refractory cardiorespiratory arrest, four were due to ventricular fibrillation, six were due to congestive heart failure and persistent low output syndrome, and four were due to sepsis. Only one death in the APAB group, which was due to sudden cardiorespiratory arrest, was related to the band procedure. In addition, 2 patients in the APAB group died of preoperative meningitis and aspiration pneumonitis and were excluded from the statistical analysis. Early reoperation was required in 17 patients (18.7%) in CPAB group for band tightening (n ⫽ 9) and band loosening (n ⫽ 8). Three patients in this group required up to four reoperations for achieving adequate band gradients. Two reoperations occurred in the APAB group: one to drain a pericardial effusion and another for a technical error that had produced band loosening. At reoperation, rebanding was performed. This difference in the number of reoperations in the two groups was statistically significant (p ⫽ 0.014). Another difference was in the postoperative inotrope requirement. All patients in CPAB group were either administered or required inotropes to adjust to the altered physiology after PAB. In the APAB group, inotropes were not used electively but were required only in 12 patients (21%) in the ICU who were preoperatively on mechanical ventilation or those who were in intractable congestive heart failure. In other patients in this group, elective inotropes were not used. The other variables, such as the ICU and hospital stay, duration of mechanical ventilation and the final band gradients, were similar in both groups. Acute events were not uncommon in either group. In CPAB group, 37 acute adverse events occurred, consisting of 14 episodes of sudden cardiorespiratory compromise, out of which 7 patients were not revived; six episodes of sudden ventricular fibrillation, out of which 2 were revived; 10 instances of sudden respiratory arrest requiring emergency endotracheal intubation and band loosening; and seven episodes of transient bradycardia and hemodynamic deterioration requiring optimizations of inotropes. In contrast, only 14 such events occurred in the APAB group, of which 6 patients had cardiorespira-

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tory arrest that responded to removal of the clip used for tightening without reoperation and no patients died. The other 8 patients required optimization of inotropes for bradycardia and altered hemodynamics. One patient required drainage of pericardial effusion and another patient required rebanding because of technical error that occurred when the clip holding the threads together slipped. Patient age, weight, and the diagnosis did not have any effect on early deaths. In the latter part of our experience with APAB, we performed this procedure in 5 sick infants with severe degrees of congestive heart failure. Three patients were on prolonged tracheostomy and mechanical ventilatory support and 2 had blood cultures that were positive for acute infective endocarditis with congestive heart failure. All these patients had gradual adjustments of band gradient after APAB and recovered, although the ventilation times were longer and they required inotropic support due to their morbid condition. One patient had an uneventful definitive operation. All patients were followed up for a mean 22.8 ⫾ 18.6 months (range, 4 to 72 months). There was significant PA distortion in 8 patients in the CPAB group and band migration in another 4. This was not observed in the APAB group. Follow-up computed tomography angiograms in 6 patients in the APAB group ruled out any kinking/tenting of the PA towards the sternum. To date, 8 patients in the CPAB group and 5 in the APAB group have undergone definitive operation. The nature of the reoperations was similar in both groups. Adequate band gradients as desired were encountered in both the groups.

Comment In the current era, early primary repair is the treatment of choice for congenital cardiac defects, and palliative procedures are required only for a limited subset of patients. Children in developing countries with high-flow lesions commonly present with malnutrition and advanced cardiac cachexia and chest infection; these patients commonly undergo PAB as an interim palliation, and definitive procedure is deferred to a later date when they are better surgical candidates for the definitive procedure [19]. Determination of optimal band tightness is often difficult, because even minor changes in the diameter of the PA have a large impact on the pulmonary blood flow and the gradient across the PAB [6]. This is further complicated by the fact that during PAB, the patient is on mechanical ventilation under general anesthesia with the chest open [20]. Within the first few hours or days after operation, there are significant alterations in heart rate and contractility, Pao2 and Paco2, acid-base status, hematocrit, and balance between systemic and pulmonary vascular resistance, and these factors compound the effect of a fixed PAB [21]. A loose PAB defeats the very purpose of the operation, whereas a tight PAB can seriously compromise the cardiac output and lead to sudden hemodynamic deterioration with cardiorespiratory compromise.

In children with functionally univentricular hearts, an age-related variability of the ventricular adaptive response is often present, particularly if they require an associated surgical procedure such as repair of coarctation of aorta or atrial septectomy [21, 22]. Progressive tightening over a period of time is very important in older patients with single-ventricle physiology and severe pulmonary hypertension. In these patients, elevated pulmonary vascular resistance does not allow shift to an immediate low level of distal PA pressures. As a result of all these problems, repeated surgical procedures are required to achieve the desired band diameter. Most of these patients require prolonged mechanical ventilatory and inotropic support, and their ICU stay is prolonged. The need for the development of an APAB arose because of these problems of the continuously variable clinical requirements requiring changes in the band width and the inability of the fixed band to fulfill these. In the 10-year period between 1992 and 2001, more than 16 different techniques of APAB were reported [6,12–15], the latest addition being the flow watch pneumatic device developed by Bonnet and colleagues [16]. These devices are effective but are expensive, require specialized equipment, and have not gained widespread acceptance due to unreliability and lack of reproducibility of adjustments. We were thus led to develop our own method of APAB, which was reported earlier in a small subset of patients. We addressed the detailed technical aspects, advantages, and concerns of this APAB system in our prior publication [17]. The most important advantages have been that it is simple and inexpensive, no specialized equipment is required, and band tightening is very gradual and under normal physiologic conditions. Our results have demonstrated a significant reduction in early deaths, need for reoperation, inotropic support, and early acute adverse events, without compromising on the degree of desired gradients. Because similar anesthesia techniques and postoperative management protocols were used in the two groups, it is unlikely that these differences could have led to changes in outcomes in the two groups. This study is a retrospective review of two different types of approaches to PAB in a particular time frame. The patients were not randomized to either of the groups, and the choice of the method of PAB was by surgeon preference in the early part of the experience. However, lately our results have prompted us to move from CPAB to APAB. Given the ease of APAB and better outcomes with our method and with that of others worldwide, it may not be ethically justifiable to conduct a prospective randomized clinical trial comparing CPAB with APAB. Patients with atrioventricular septal defects may have a stormier postoperative course after PAB, and more of these patients were in the CPAB group. However, the differences in numbers between the two groups were not statistically significant. With our current results we feel that these patients may actually have a more predictable course with the use of APAB. The two groups of patients belong to two different time frames, which may alter the results. These patients all belong to the same decade; however, and as pointed out

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earlier, we now have more predictable outcomes with APAB compared with CPAB, despite the change of the surgical era, because the results of CPAB still continue to be unpredictable worldwide [11]. In conclusion, encouraged by change in outcomes with the use of APAB, patients requiring PAB are now offered APAB, and we are now able to achieve better outcomes in even the most unsuitable patients in poor general condition.

References 1. Muller WH Jr, Dammann JE. The treatment of certain congenital malformations of the heart by creation of pulmonary stenosis to reduce pulmonary hypertension and excessive pulmonary blood flow: a preliminary report. Surg Gynecol Obstet 1952;95:213. 2. Patel RG, Jhenacho HN, Abrams LD, et al. Pulmonary artery banding and subsequent repair in ventricular septal defect. Br Heart J 1973;35:651– 6. 3. Sivakumar K, Anil SR, Rao SG, Shivaprakash K, Kumar RK. Closure of muscular ventricular septal defects guided by en face reconstruction and pictorial representation. Ann Thorac Surg 2003;76:158 – 66. 4. Lee JR, Choi JS, Kang CH, Bae EJ, Kim YH, Rho JR. Surgical results of patients with a functional single ventricle. Eur J Cardiothorac Surg 2003;24:716 –22. 5. Lan YT, Chang RK, Laks H. Outcome of patients with double inlet left ventricle or tricuspid atresia with transposed great arteries. J Am Coll Cardiol 2004;43:113–9. 6. Corno AF. Pulmonary artery banding. Swiss Med Wkly 2005;135:515–9. 7. Jonas RA, Giglia TM, Sanders SP, et al. Rapid, two-stage arterial switch for transposition of the great arteries and intact ventricular septum beyond the neonatal period. Circulation 1989;80:1203– 08. 8. Stewart S, Harris P, Manning J. Pulmonary artery banding: an analysis of current risks, results and indications. J Thorac Cardiovasc Surg 1980;80:431– 6. 9. Kron IL, Nolan SP, Flanagan TL, Gutgesell HP, Muller WH Jr. Pulmonary artery banding revisited. Ann Surg 1989;209: 642–7. 10. Horowitz MD, Culpepper WS III, Williams LC III, SundgaardRiIsi K, Ochsner JL. Pulmonary artery banding: analysis of a 25-year experience. Ann Thorac Surg 1989;48:444 –50. 11. Takayama H, Sekiguchi A, Chikada M, Noma M, Ishizawa A, Takamoto S. Mortality of pulmonary artery banding in the current era: recent mortality of PA banding. Ann Thorac Surg 2002;74:1219 –24. 12. Dajee H, Benson L, Laks H. An improved method of pulmonary artery banding. Ann Thorac Surg 1984;37:254 –7. 13. Emmanuel LB, Bonhoeffer P, Folliguet TA, et al. A new percutaneously adjustable, thoracoscopically implantable, pulmonary artery banding: an experimental study. Ann Thorac Surg 2001;72:1358 – 61. 14. Warren ET, Heat BJ, Brand WW. A staged expanding pulmonary artery band. Ann Thorac Surg 1992;54:240 –3. 15. Vince DJ, Culham JAG. A prosthesis for banding of the main pulmonary artery, capable of serial dilatation by balloon angioplasty. J Thorac Cardiovasc Surg 1989;97:421–7. 16. Bonnet D, Corno AF, Sidi D, et al. Early clinical results of the telemetric adjustable pulmonary artery banding Flo WatchPAB. Circulation 2004;110(suppl 1):II158 – 63. 17. Choudhary SK, Talwar S, Airan B, et al. A new technique of percutaneously adjustable pulmonary artery banding. J Thorac Cardiovac Surg 2006;131:621– 4. 18. Trusler GA, Mustard WT. A method of banding the pulmonary artery for large isolated ventricular septal defect with and without transposition of the great arteries. Ann Thorac Surg 1972;13:351–5.

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19. Bhan A, Agarwal S, Saxena P, Venugopal P. Minimally invasive pulmonary artery banding: a new approach. Indian Heart J 2004;56:37–20. 20. Corno AF. Revised pulmonary artery banding. Ann Thorac Surg 2000;69:1295– 6. 21. Tchervenkov CI, Shum-Tim D, Beland MJ, Jutras L, Platt R. Single ventricle with systemic obstruction in early life:

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comparison of initial pulmonary artery banding versus the Norwood operation. Eur J Cardiothorac Surg 2001;19:671–7. 22. Wernovsky G, Giglia TM, Jonas RA, Mone SM, Colan SD, Wessel DL. Course in the intensive care unit after “preparatory” pulmonary artery banding and aortopulmonary shunt placement for transposition of the great arteries with low left ventricular pressure. Circulation 1992;86:II133–22.

INVITED COMMENTARY Talwar and colleagues [1] report the follow-up of a technique for adjustable pulmonary artery banding (PAB) [2], which is a timely and important topic particularly because of several controversial issues. There is an evident contrast between the general opinion that PAB is almost an abandoned procedure (at least in Western countries) and the data collected in the official North American and European database. The total number of PAB procedures reported in The Society of Thoracic Surgery (STS) congenital database was 739 for the period from 2002 to 2005, corresponding to 1.9% of the total surgical procedures (739 of 38,431); whereas the total number of PAB procedures reported in the European Association Cardio-Thoracic Surgery (EACTS) congenital database was 711, corresponding to 2.0% of the total surgical procedures (711 of 35,575). These figures contrast with the opinion that PAB is an abandoned procedure. Another frequent disagreement is the indication for PAB, generally only considered as preparation for a univentricular type of repair or rarely for left ventricular retraining. In The STS congenital database for the 711 of 739 procedures with a diagnosis where it was identifiable, the indication for PAB in 28 cases was diagnosed as “missing” or “miscellanea”, in 400 procedures (ie, 400 of 711; 56%) the indication was in view of bi-ventricular types of repair, in 276 procedures (ie, 276 of 711; 39%) it was for univentricular types of repair, and in 35 (ie, 35 of 711; 5%) it was for left ventricular re-training. Recent reports confirm the use of PAB for ventricular septal defects associated with aortic arch hypoplasia or interruption, but also for more controversial situations like multiple ventricular septal defects and complete atrioventricular septal defects. In the last two groups of malformations, the two-stage approach with PAB is considered for patients coming to surgery after long periods with malnutrition, infections, and mechanical ventilation, particularly in the presence of advanced pulmonary hypertension, as a lower risk alternative to the primary repair. The indication for PAB has also been accepted as an alternative surgical option in transposition of the great arteries with late referral and congenitally corrected transposition of the great arteries in which left ventricular re-training is required, and hypoplastic left heart malformations as a rescue procedure in critically ill neonates or as an elective procedure in preparation for subsequent surgery (ie, either the Norwood procedure or a heart transplant). The continued interest in adjustable PAB has also been confirmed in recent experimental [3] and clinical studies of new techniques, such as the one already proposed by Talwar and colleagues [1]. The adjustable PAB provides © 2008 by The Society of Thoracic Surgeons Published by Elsevier Inc

evident clinical advantages for conventional PAB, as demonstrated by this study [1]. Furthermore, the flexibility provided by the device for telemetrically controlled PAB (FloWatch-PAB; EndoArt, Lausanne, Switzerland) [4, 5] provides additional advantages because: (1) it eliminates the need for reoperation to adjust the PAB, not only in the early postoperative period, as for the technique of Talwar and colleagues [1], but for as many as 3 years after hospital discharge [4, 6]; (2) postoperative management is simplified and postoperative mechanical ventilation, length of stay in the intensive care unit (ICU) and in the hospital are significantly reduced, even in more compromised and difficult to manage infants, such as the ones with associated anomalies, excluded in the study of Talwar and colleagues [1]; (3) the cost of the device is more than offset by the reduction in duration of postoperative mechanical ventilation, length of stay in the ICU and in the hospital, and avoidance of any PAB-related reoperation [6]; and (4) pulmonary artery reconstruction is not required any more when intracardiac repair is undertaken [5, 6]. Antonio F. Corno, MD, FRCS Department of Cardiac Surgery Alder Hey Children Hospital Eaton Rd Liverpool L12 2AP, United Kingdom e-mail: [email protected]

References 1. Talwar S, Choudhary SK, Mathur A, et al. Changing outcomes of pulmonary artery banding with the percutaneously adjustable pulmonary artery band. Ann Thorac Surg 2008;85: 593– 8. 2. Choudhary SK, Talwar S, Airan B, et al. A new technique of percutaneously adjustable pulmonary artery banding. J Thorac Cardiovasc Surg 2006;131:621– 4. 3. Faber MJ, Dalinghaus M, Lankhuizen IM. Right and left ventricular function after chronic pulmonary artery banding in rats assessed with biventricular pressure-volume loops. Am J Physiol Heart Circ Physiol 2006;291:H1580 – 6. 4. Corno AF, Bonnet D, Sekarski N, Sidi D, Vouhé P, von Segesser LK. Remote control of pulmonary blood flow: initial clinical experience. J Thorac Cardiovasc Surg 2003;126:1775– 80. 5. Corno AF, Prosi M, Fridez P, Zunino P, Quarteroni A, von Segesser LK. The non-circular shape of FloWatch-PAB prevents the need for pulmonary artery reconstruction after banding. Computational fluid dynamics and clinical correlations. Eur J Cardiothorac Surg 2006;29:93–9. 6. Corno AF, Ladusans EJ, Pozzi M, Kerr S. FloWatch versus conventional pulmonary artery banding. J Thorac Cardiovasc Surg 2007;134:1413–20. 0003-4975/08/$34.00 doi:10.1016/j.athoracsur.2007.08.034