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Mechanical circulatory support in patients with heart failure secondary to transposition of the great arteries

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Mechanical circulatory support in patients with heart failure secondary to transposition of the great arteries
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  INNOVATION Mechanical circulatory support in patients with heartfailure secondary to transposition of the great arteries David L. Joyce, MD, a Sheri S. Crow, MD, MS, b Ranjit John, MD, c  James D. St. Louis, MD, d Elizabeth A. Braunlin, MD, e Lee A. Pyles, MD, e Paula Kofflin, RN, e and Lyle D. Joyce, MD, PhD f  From  a  Department of Cardiothoracic Surgery, Stanford University Medical Center, Palo Alto, California;  b  Department of Pediatrics Mayo Clinic, Rochester, Minnesota, and   f   Division of Cardiac Surgery Mayo Clinic, Rochester, Minnesota;  c  Divisionof Cardiovascular Surgery,  d   Division of Pediatric Cardiac Surgery, and   e  Division of Pediatric Cardiology, University of  Minnesota, Minneapolis, Minnesota Advances in palliation of congenital heart disease have resulted in improved survival to adulthood.Many of these patients ultimately develop end-stage heart failure requiring left ventricular assist deviceimplantation (LVAD). However, morphologic differences in the systemic ventricle of these patientsrequire careful attention to cannula placement. We report on the evolution of our surgical technique forimplanting LVADs in 3 patients with transposition of the great arteries and congenitally correctedtransposition of the great arteries. Applying standard LV cannulation techniques to the systemicventricle led us too anteriorly in our first patient, creating obstruction by the moderator band.Subsequent use of epicardial and transesophageal echocardiography allowed for intraoperative local-ization of the intracardiac muscular structures to identify the optimal cannulation site. The acute angleof the inflow cannula on the DeBakey LVAD (MicroMed Technology, Houston, TX) required flippingthe device 180°. The HeartMate II device (Thoratec, Pleasanton, CA) could be shifted towards themidline. One patient underwent successful transplant and 2 are home waiting for a donor organ. Weconclude from our experience that LVAD surgery can be safely performed in patients with congenitalheart disease when implanted under echocardiographic guidance.J Heart Lung Transplant 2010;29:1302–5© 2010 International Society for Heart and Lung Transplantation. All rights reserved. KEYWORDS: mechanical circulatorysupport;transposition of thegreat arteries;congenitally correctedtransposition of thegreat arteries;systemic rightventricule;heart failure;epicardialechocardiography Transposition of the great arteries (TGA) and congeni-tally corrected transposition of the great arteries (CCTGA)occur in a wide variety of morphologic variants with dif-fering clinical presentations. In TGA, the aorta arises fromthe morphologic right ventricle (RV), whereas the pul-monary artery arises from the morphologic left ventricle(LV) in a configuration that produces ventriculoarterialdiscordance. 1 CCTGA is characterized by atrioventricular and ven-triculoarterial discordance in which a morphologic LVprovides the pulmonary circulation. 2 In this anomaly, thesystemic atrioventricular valve (SAVV) is a morphologictricuspid valve, whereas the pulmonary atrioventricularvalve (PAVV) is a mitral valve (Figure 1). Despite ade- quate repair, patients with systemic RVs have an in-creased risk for developing heart failure accompanied bya high mortality rate. 3 This tendency toward systemic ventricular failure hasbeen attributed to a sustained compensatory response of thecoronary circulation to the augmented work load  4 as well asmorphologic attributes of the RV that make it sub-optimal Reprint requests: David L. Joyce, MD, 162 Charles Marx Way, PaloAlto, CA 94304. Telephone: 650-450-1685. Fax: 713-797-0613.E-mail address: djoyce4@gmail.comhttp://www.jhltonline.org1053-2498/$ -see front matter © 2010 International Society for Heart and Lung Transplantation. All rights reserved.doi:10.1016/j.healun.2010.05.030  for supporting the systemic circulation. For instance, thespongy, trabeculated character of the RV muscle combinedwith a relative mechanical inefficiency of the tricuspid sub-valvular apparatus frequently result in ventricular failurewhen these structures are subjected to the higher pressuresof systemic circulation. These anomalies are characterizedby progressive disease. Congestive heart failure will de-velop by age 45 in 67% of CCTGA patients with associatedlesions and in 25% of patients without associated lesions. 5 Failure of the systemic ventricle occurred in 7.7% of pa-tients in one series after atrial correction of TGA. 6 Cardiac transplantation is required in 13% of adult pa-tients with CCTGA. 2 Although a small handful of casereports have described implantation of a left ventricularassist device (LVAD) in patients with systemic RVs, thetechnical features of these procedures are not well describedand all used pulsatile VADs. We report on the surgicalchallenges of 3 patients with abnormal septation of theconotruncus that required mechanical circulatory support asa bridge to transplant using axial-flow pumps. Case reports Patient 1 The first patient was a 35-year-old man with CCTGA whodeveloped significant biventricular failure with diminishedfunctional capacity and compromised organ function. Me-chanical circulatory support was initiated with a DeBakeyVAD (MicroMed, Technology, Houston, TX) as a bridge totransplant. At the time of surgery, the systemic ventriclewas confirmed to be a morphologic RV and was positionedanteriorly within the chest. The site of inflow cannula in-sertion was selected, and the apical coring device was usedto create an opening in the ventricle. A significant number of trabeculae were encountered within the ventricle, and thesewere excised down to the papillary muscles. The sewing ringwas sutured in place, and the device was inserted.After the outflow graft was anastomosed to the ascendingaorta, the pump was turned on and flows were monitored.As the heart was filled in weaning from cardiopulmonarybypass, the LVAD flows were noted to be much lower thanexpected, with a maximum flow rate of 0.5 liters/min. Ma-nipulation of the pump positioning appeared to result in adramatic improvement in flow rates, and for this reason, thepatient was placed back on cardiopulmonary bypass to ro-tate the device 180° (Figure 2). This maneuver resulted in an improvement of flows up to 2.5 liters/min. This patientunderwent successful transplantation. Patient 2 The second patient was a 33-year-old man with dextro-TGA(DTGA) who was treated with a Mustard procedure (inter-atrial baffle) as a child. He presented with florid congestiveheart failure and supersystemic pulmonary hypertension.Home milrinone therapy had failed. Using a combination of transesophageal and epicardial echo, we were able to locatean ideal position for inflow cannula placement. The 2-cmcore was created more inferiorly than one would expectfrom the usual palpation of the “dimple” at the apex of theventricle. This brought us into a position between the 2papillary muscles. With further trimming of the trabeculaeand moderator band, we were able to find a location thatallowed complete freedom of possible inflow obstruction.The patient has enjoyed excellent flows with a HeartMate II(Thoratec, Pleasanton, CA) LVAD and has been home formore than 2 years waiting for an appropriate donor. Figure 1  Anatomic challenges associated with ventricular assistdevice implantation in a morphologic right ventricle (RV). LV, leftventricle. (A) Transposition of the great arteries. (B) Congenitallycorrected transposition of the great arteries. 1303Joyce et al. LVAD Implantation for TGA/CCTGA  Patient 3 The third patient was a 25-year-old woman with DTGAwho also had a Mustard procedure as an infant. She requiredimplantation of a HeartMate II LVAD as bridge to trans-plant. The same technique as outlined in the second patientwas used in locating the ideal spot for cannula placementsomewhat posterior to the moderator band. Multiple trabeculaeand the moderator band were resected; however, the anteriorpapillary muscle still appeared to be a potential source of obstruction in a low ventricular volume state. A significantportion of the papillary muscle was resected, and a pledgetedsuture was used to support the attachment superiorly. Thisprovided excellent flow, and the patient has been free of prob-lems while she lives at home waiting for a donor heart. Discussion Systemic ventricular failure is a known complication after aSenning or Mustard procedure because the morphologic RVmust function as the systemic ventricle. 1 In a series of patients operated on between 1974 and 1982, 7 of 88 pa-tients undergoing a Mustard procedure for TGA requiredreoperation for systemic ventricular failure. 7 Late systemicventricular failure during the second and third decades of lifein patients with anatomic repair procedures or in those withCCTGA poses few options. In patients with biventricular fail-ure, transplantation is the treatment of choice, and data showthat long-term survival is equivalent to non-congenital heartfailure patients once the peri-operative risk (which may be ashighas60%)isexcluded. 8,9 CCTGApatientsalsodemonstratea high incidence of systemic ventricular failure, often requiringtransplantation. 5 If rapid deterioration of cardiac function en-sues before a donor heart becomes available, the use of anLVAD may be the only option for these patients. The uniqueanatomic variants associated with TGA and CCTGA mandatea thoughtful approach to LVAD implantation into a morpho-logic RV to prevent adverse outcomes.Implantation of an LVAD in a patient with TGA aftersurgical repair was first described by Wiklund et al, 10 whoachieved a successful outcome using a HeartMate device in ateenager who had undergone a Mustard procedure 15 yearspreviously. Owing to the small size of the patient, the pumpwas placed intraperitoneally. In addition, the position of thesystemic ventricle required implantation in a “back-to-front,”or upside down position with the outflow cannula directed intothe left chest. The inflow cannula was placed in the diaphrag-matic wall rather than the apex of the systemic ventricle.Subsequent work by Stewart et al 8 achieved successfulbridge to transplant in 2 patients (1 after a Senning and 1CCTGA) using a TCI HeartMate (pulsatile) LVAD. Bothpumps were placed intraperitoneally, but the outflow graftswere directed to the right with the device shifted to the rightbut in the normal orientation. This configuration required 1patient’s in-flow cannula to srcinate from the free wall of the RV. RV failure developed in the other patient after atricuspid valve replacement. The tricuspid valve was re-moved during LVAD implantation, creating a single-chamberleft atrium/right ventricle. The inflow cannula was placedthrough an apical core that was removed from the RV. Despitethis unorthodox technique, the patient was well supported for8 months before successful transplantation. Interestingly, mid-line abdominal wound dehiscence developed in both patientsas a result of the tension created from placing the LVAD in amore medial position. Other reports in the literature include a13-year-old with TGA that underwent Thoratec implantationthat was complicated by a cerebrovascular accident 9 as well asa successful HeartMate I implant in a 17-year-old with TGAstatus after Mustard repair as an infant. 11 The advent of smaller axial-flow assist devices has essen-tially eliminated the problem of dehiscence secondary to ex-cess tension on the wound. In many instances, however, thegeometric advantages of positioning a smaller pump in thechest are offset by impairment of VAD flows due to obstruc-tion of the inflow cannula. Echocardiography has becomeindispensable in these cases for attaining optimal pump posi-tioning. Scohy et al 12 have recently described the utility of transesophageal echocardiography in detecting RV failure dur- Figure 2  Representative chest X-rays demonstrate the altered configuration of the pump position. 1304 The Journal of Heart and Lung Transplantation, Vol 29, No 11, November 2010  ing device exchange between a Levitronix device (Levitronix,Waltham, MA), and Berlin Heart (Berlin Heart GmbH, Berlin,Germany) in 5 patients. In our experience, epicardial echocar-diography represents another useful technique for identifyingtrabeculae or papillary muscles that may impair ventriculardecompression by obstructing flow to the assist device.CCTGA and DTGA are both characterized by a morpho-logic RV that must support the systemic circulation. How-ever, the position of the systemic RV is different betweenthe 2 groups. In DTGA, the systemic RV lies anteriorly orto the right side in the normal anatomic position. In contrast,the systemic RV in CCTGA lies posterior or leftward in theposition of a normal LV. In this anomaly, there is alsofrequent dextrorotation of the heart. These differencespresent distinct challenges with respect to cannula insertion.Optimal cannula placement is achieved when the inflowcannula is directed toward the atrioventricular valve. Wehave observed a dramatic effect on pump flows as a conse-quence of the position of the inflow cannula relative to themoderator band. The natural tendency is to place the can-nula too anterior at the palpable “dimple,” resulting inimpaired flows due to obstruction of the inflow cannula bythe moderator band and anterior papillary muscles.When the insertion site was moved more posterior to themoderator band, a dramatic improvement in blood flow wasappreciated. The orientation of the ventricle in CCTGA mayrequire unconventional positioning of the pump dependingon the angulation of the inflow cannula. In our experiencewith the DeBakey pump in CCTGA, we found that 180°rotation of the pump and more posterior placement avoidedinflow obstruction (Figure 2). In the case of DTGA, the best configuration for the inflow cannula is again posterior to themoderator band, which puts the pump more on the diaphrag-matic surface of the heart. The configuration of the HeartMateII did not require malrotation of the pump but placement moreto the right than one sees in non-TGA patients. One must bevery liberal in resecting major portions of the moderator band.With respect to the management of significant tricuspid regur-gitation, our experience suggests that it is well tolerated in thepresence of adequate pump flows and should not prompt at-tempts at surgical repair at the time of implantation.Implantation of an axial-flow assist device into a mor-phologic RV represents a technique that is likely to beperformed with increasing frequency in the years ahead asmore patients present with long-term systemic ventricularfailure after Mustard and Senning operations. Although theimplementation of arterial switch operations may eventuallydispel the importance these techniques, it is likely that theywill become increasingly relevant in the management of patients with biventricular failure. Early data are limited,but feasibility studies at the Texas Heart Institute havedemonstrated satisfactory biventricular support in calvesthat underwent RVAD implantation with a Jarvik 2000device (Jarvik Heart, Inc. New York, NY). 13 With an in-creasing number of patients requiring mechanical supportfor the left ventricle, RV failure is likely to increase inimportance. Therefore, the principles of optimal device in-sertion in patients with morphologic RVs will become in-creasingly relevant in the years ahead.In conclusion, the LVAD offers additional options foradults with congenital heart disease who experience end-stagecardiac failure. A combination of epicardial as well as trans-esophageal echocardiographic guidance to optimal LVAD in-flow cannula placement ensures successful cardiac supportfor patients with TGA. A thorough understanding of theanatomy as well as a willingness to aggressively removemoderator bands, trabeculae, or papillary muscles is re-quired to ensure superior results of unobstructed flow. Disclosure statement None of the authors has a financial relationship with acommercial entity that has an interest in the subject of thepresented manuscript or other conflicts of interest to disclose. References 1. Warnes CA. Transposition of the great arteries. Circulation 2006;114:2699-709.2. Beauchesne LM, Warnes CA, Connolly HM, Ammash NM, Tajik AJ,Danielson GK. Outcome of the unoperated adult who presents withcongenitally corrected transposition of the great arteries. J Am CollCardiol 2002;40:285-90.3. Piran S, Veldtman G, Siu S, Webb GD, Liu PP. Heart failure andventricular dysfunction in patients with single or systemic right ven-tricles. Circulation 2002;105:1189-94.4. Hauser M, Bengel FM, Hager A, et al. Impaired myocardial blood flowand coronary flow reserve of the anatomical right systemic ventricle inpatients with congenitally corrected transposition of the great arteries.Heart 2003;89:1231-5.5. Graham TP Jr, Bernard YD, Mellen BG, et al. Long-term outcome incongenitally corrected transposition of the great arteries: a multi-institutional study. J Am Coll Cardiol 2000;36:255-61.6. Turina MI, Siebenmann R, von Segesser L, Schonbeck M, Senning A.Late functional deterioration after atrial correction for transposition of the great arteries. Circulation 1989;80:I162-7.7. Horer J, Herrmann F, Schreiber C, et al. How well are patients doingup to 30 years after a mustard operation? Thorac Cardiovasc Surg2007;55:359-64.8. Stewart AS, Gorman RC, Pocchetino A, Rosengard BR, Acker MA.Left ventricular assist device for right side assistance in patients withtransposition. Ann Thorac Surg 2002;74:912-4.9. Undar A, McKenzie ED, McGarry MC, et al. Outcomes of congenitalheart surgery patients after extracorporeal life support at Texas Chil-dren’s Hospital. Artif Organs 2004;28:963-6.10. Wiklund L, Svensson S, Berggren H. Implantation of a left ventricularassist device, back-to-front, in an adolescent with a failing mustardprocedure. J Thorac Cardiovasc Surg 1999;118:755-6.11. George RS, Birks EJ, Radley-Smith RC, Khaghani A, Yacoub M.Bridge to transplantation with a left ventricular assist device for sys-temic ventricular failure after Mustard procedure. Ann Thorac Surg2007;83:306-8.12. Scohy TV, Gommers D, Maat AP, Dejong PL, Bogers AJ, Hofland J.Intraoperative transesophageal echocardiography is beneficial for he-modynamic stabilization during left ventricular assist device implan-tation in children. Paediatr Anaesth 2009;19:390-5.13. Radovancevic B, Gregoric ID, Tamez D, Vrtovec B, Tuzun E, CheeHK, et al. Biventricular support with the Jarvik 2000 axial flow pump:a feasibility study. ASAIO J 2003;49:604-7. 1305Joyce et al. LVAD Implantation for TGA/CCTGA
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