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The Journal of Heart and Lung Transplantation, Vol 33, No 4, April 2014
Figure 1 (A) The inflow cannula is seen protruding out of the skin. (B) Ultrasound imaging shows a 4.4-cm-long thrombus floating in the left atrium. (C) The inflow cannula was removed with the adhered thrombus at the tip of the cannula.
Supplementary material A supplementary video is available in the online version of this article at jhltonline.org.
References 1. Klotz S, Meyns B, Simon A, et al. Partial mechanical long-term support with the CircuLite Synergy pump as bridge-to-transplant in congestive heart failure. Thorac Cardiovasc Surg 2010;58(Suppl 2): S173-8.
Diffuse rhabdomyomatosis presenting as infantile hypertrophic cardiomyopathy Sabrina Law, MD,a Terrence Chun, MD,a and Raj Kapur, MDb From the aDivision of Pediatric Cardiology; and the bDivision of Pathology, Seattle Children’s Hospital, Seattle, Washington.
Diffuse ventricular thickening is often attributed to hypertrophic cardiomyopathy (HCM).1 We present a case of HCM with an unusual pathologic diagnosis. A 2-hour-old neonate presented with supraventricular tachycardia (SVT). Echocardiography demonstrated severe biventricular thickening with no outflow tract obstruction and normal function. Within 2 weeks, she developed low cardiac output with left ventricular outflow tract obstruction (3.7 m/s), and a doubling of interventricular septal wall thickness (diastolic dimension 2.02 cm, z-score ¼ 24.7, previously 1.1 cm, z-score ¼ 10.7). Gene testing was negative for Noonan syndrome and sarcomeric hypertrophic cardiomyopathy (HCM), as was screening for inborn errors of
2. Meyns B, Klotz S, Simon A, et al. Proof of concept: hemodynamic response to long-term partial ventricular support with the synergy pocket micro-pump. J Am Coll Cardiol 2009;54:79-86. 3. Meyns BP, Simon A, Klotz S, et al. Clinical benefits of partial circulatory support in New York Heart Association class IIIB and early class IV patients. Eur J Cardiothorac Surg 2011;39:693-8. 4. Sainte S, Gewillig M, Droogne W, et al. Explantation of a CircuLite left ventricular assist device without removal of the inflow cannula: how to do it? Interact Cardiovasc Thorac Surg 2013, http://dx.doi.org/10.1093/ icvts/ivt488: [E-pub ahead of print]. 5. Schmack B, Gorenflo M, Rengier F, Ruhparwar A. Extempore interventional closure of a broken CircuLite Synergy micropump inflow graft defect. J Heart Lung Transplant 2013;32:1140-1.
metabolism. Clinical examination was negative for features of tuberous sclerosis complex (TSC). Abdominal and brain magnetic resonance images were normal. The patient had recurrent hemodynamically significant episodes of SVT that worsened despite multiple antiarrhythmic medications. Intracardiac electrophysiology study revealed a retrograde-conducting, right-sided accessory pathway, which was ablated successfully. An intermittently conducting, concealed, left-sided pathway was not ablated. Due to complete atrioventricular block, she received a permanent dual-chamber pacemaker 10 days later. Shortly thereafter, she developed periods of pacemaker-mediated tachycardia, where ventricular pacing was conducted retrograde via accessory pathway to the atrium, tracked by the device, and then re-propagated back to the ventricle. To prevent this, the device was programmed to asynchronous (VVI) pacing. The patient then had cardiovascular collapse requiring extracorporeal cardiopulmonary resuscitation (ECPR), followed by progressive ventricular dysfunction, and was listed for transplantation. She developed new pre-excitation
Case Anecdotes, Comments and Opinions
453
Figure 1 (A) Gross and microscopic pathology of diffuse rhabdomyomatosis. (A) A formalin-fixed transverse section of the right and left ventricles, just apical to the atrioventricular valves, demonstrates biventricular mural hypertrophy and mottled regions of deeper tan and a pale myocardium. (B) A montage of photomicrographs from the left ventricle illustrates replacement of large, irregularly shaped zones in the myocardium by rhabdomyoma cells, which have abundant clear cytoplasms. (C) At higher magnification, enlargement and central vacuolization characterizes the rhabdomyoma cells, in contrast to adjacent histologically normal (nl) cardiac myocytes. (D) Rare “spider cells” (arrow), with central nuclei, large peripheral cytoplasmic vacuoles and intervacuolar eosinophilic cytoplasm, were present in the rhabdomyoma. (B) Rhabdomyoma involvement in the cardiac conduction system. A trichrome-stained longitudinal section through the right atrium and ventricle demonstrates the atrioventricular bundle (AVB), most of which is replaced by rhadomyoma. The inset shows a portion of the AVB (dashed rectangle) at higher magnification. More extensive atrial involvement was present in other sections.
with a surface delta wave pattern consistent with a left-sided accessory pathway, which resulted in 1:1 conducted sinus rhythm, increased ventricular rate and worse ventricular dysfunction. The pacemaker was reprogrammed to function as a resynchronization pacemaker by delivering right ventricular pacing simultaneous with left-sided pre-excitation, which normalized her QRS complex. Left ventricular outflow tract obstruction resolved, but posterior wall and interventricular septal thicknesses fluctuated. Severe heart failure was managed with inotropes and mechanical ventilation until orthotopic heart transplantation at 4 months of age. The patient’s explanted heart weighed 157 g (normal range 30 ⫾ 6 g) and demonstrated biventricular hypertrophy (Figure 1A). The heart was infiltrated by irregularly shaped lesions that replaced the majority of her myocardium and
portions of the conduction system (Figure 1B). Large myocytes with vacuolated cytoplasms and rare “spider cells” comprised the lesions. This pathology has been termed “diffuse rhabdomyomatosis” in 4 earlier reports, all with similar features to those seen in the patient described here.2 Diffuse rhabdomyomatosis is associated with refractory arrhythmias and heart failure in infancy. The infiltrative nature of diffuse rhabdomyomatosis is unlike the discrete cardiac rhabdomyomas characteristic of TSC. Although the common non-infiltrative rhabdomyomas associated with TSC have a benign course and often regress in early childhood,3 the natural history of diffuse rhabdomyomatosis is quite different.2 All children described in earlier reports died, yet none with other signs of TSC. Because it is possible that other features of TSC may have arisen later had
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The Journal of Heart and Lung Transplantation, Vol 33, No 4, April 2014
these patients survived,3 the patient described in this study will be followed by a medical geneticist. SVT is the most common arrhythmia with cardiac tumors in the neonatal period, and rhabdomyoma can be associated with ventricular pre-excitation.4 Evolution of inconsistent arrhythmia types suggests that the patient’s re-entrant tachycardia was not mediated by an embryonic accessory pathway. Destruction of the conduction system has been described in diffuse rhabdomyomatosis,5 and likely explains the unusual progression of this patient’s arrhythmias. Analogous alternate routes of conduction have been described in glycogen-storage disease, whereby diffuse myocardial infiltration may connect atrial and ventricular myocardium, resulting in pre-excitation. The differential diagnosis for infantile HCM includes primary sarcomeric defects, infiltrative cardiomyopathies with diagnosable biochemical perturbations, and syndromic cardiomyopathies. However, the presence of refractory arrhythmias and fluctuating wall thickness changes in a patient with diffuse ventricular thickening may indicate an alternative diagnoses, such as diffuse rhabdomyomatosis. This patient’s clinical course was atypical for sarcomeric HCM. Her early, severe and rapid progression to heart failure, recalcitrant SVT, and evolving arrhythmias were clues to a diagnosis other than HCM, which may have changed our approach to management. If diffuse rhabdomyomatosis was suspected and confirmed by biopsy, an electrophysiology study with the potential for decompensation would not have been pursued
Intraoperative transesophageal echocardiographic guidance of total artificial heart implantation Nowell M. Fine, MD,a Radha S. Gopalan, MD,b Francisco A. Arabia, MD,c Sudhir S. Kushwaha, MD,a and Krishnaswamy Chandrasekaran, MDa,b From the aDivision of Cardiovascular Diseases, Department of Medicine, Mayo Clinic, Rochester, Minnesota; b Division of Cardiovascular Diseases, Department of Medicine, Mayo Clinic, Scottsdale, Arizona; and the cDivision of Cardiovascular Surgery, Department of Surgery, Cedars-Sinai Medical Center, Los Angeles, California
For advanced heart failure patients who are candidates for mechanical circulatory support (MCS) but are at increased risk for poor outcomes after left ventricular assist device implantation, the total artificial heart (TAH) has become an important therapeutic option.1–3 The SynCardia TAH (SynCardia Systems Inc, Tucson, AZ) became the first TAH approved for use in the United States in 2004, and the number TAH-implanting centers is growing.2 Centers that perform echocardiography on MCS-supported patients have endeavored to characterize the signs of abnormal device function to deliver useful information in a timely manner. However, little is known about the role of intraoperative (IO) transesophageal echocardiography (TEE) during TAH implantation. In this report, we describe the role of IO-TEE during TAH implantation and discuss the utility and limitations of IO-TEE guidance.
aggressively. Given the natural history of diffuse rhabdomyomatosis, ablation could have been avoided and transplantation may have been pursued earlier, which is important because early transplant outcomes are directly related to the need for extracorporeal membrane oxygen (ECMO) support before transplantation.
Disclosure statement The authors have no conflicts of interest to disclose. We thank Lawrence Merritt, MD, for valuable input.
References 1. Coates TL, McGahan JP. Fetal cardiac rhabdomyomas presenting as diffuse myocardial thickening. J Ultrasound Med 1994;13:813-6. 2. Shrivastava S, Jacks JJ, White RS, et al. Diffuse rhabdomyomatosis of the heart. Arch Pathol Lab Med 1977;101:78-80. 3. Verhaaren HA, Venaaker O, De Wolf D, et al. Left ventricular outflow obstruction in rhabdomyoma of infancy: meta-analysis of the literature. J Pediatr 2003;143:258-63. 4. Gotlieb AI, Chan M, Palmer WH, et al. Ventricular preexcitation syndrome. Accessory left atrioventricular connection and rhabdomyomatous myocardial fibers. Arch Pathol Lab Med 1977;101:486-9. 5. Mandke JV, Kinare SG, Phatak AM. Congenital diffuse rhabdomyomatosis of the heart with biventricular outflow obstruction. Indian Heart J 1992;44:187-8.
Echocardiographic imaging of the TAH requires a thorough understanding of the device and its components, as well as the implantation procedure. During implantation, the ventricular portion of the recipient heart is excised, leaving only a rim of ventricular myocardium. The atria and their respective venous connections are left intact and form the atrial chambers of the TAH. The aortic and pulmonary roots are excised just above the aortic and pulmonary valves, leaving the distal ascending aorta and distal main pulmonary artery (PA) intact. The SynCardia TAH unit has 2 separate pneumatic pumping chambers, representing the left and right ventricles (the TAH components are illustrated in Supplementary Figure 1, available on the jhltonline.org Web site). The TAH also contains four Medtronic-Hall single-tilting disk valve prostheses (Medtronic-Hall, Medtronic, Minneapolis, MN) in each valvular position. Each pneumatic pumping chamber has an inlet valve representing the mitral and tricuspid valve and an outlet valve representing the aortic and pulmonary valve. The pneumatic pumping chambers are sutured to the rim of the ventricular myocardium adjoining the atrioven tricular groove. The outlet valves are connected to the retained native ascending aorta and PA, respectively, by a conduit. The diaphragms within each pumping chamber are pneumatically driven by an external driver that is connected by left and right drivelines tunneled extraperitoneally through the abdominal wall. The retention of both atria provide for an excellent imaging window of the TAH from the middle and upper esophageal IO-TEE imaging windows. Figure 1 shows IO-TEE images
The Journal of Heart and Lung Transplantation, Vol 33, No 4, April 2014
Figure 1 (A) The inflow cannula is seen protruding out of the skin. (B) Ultrasound imaging shows a 4.4-cm-long thrombus floating in the left atrium. (C) The inflow cannula was removed with the adhered thrombus at the tip of the cannula.
Supplementary material A supplementary video is available in the online version of this article at jhltonline.org.
References 1. Klotz S, Meyns B, Simon A, et al. Partial mechanical long-term support with the CircuLite Synergy pump as bridge-to-transplant in congestive heart failure. Thorac Cardiovasc Surg 2010;58(Suppl 2): S173-8.
Diffuse rhabdomyomatosis presenting as infantile hypertrophic cardiomyopathy Sabrina Law, MD,a Terrence Chun, MD,a and Raj Kapur, MDb From the aDivision of Pediatric Cardiology; and the bDivision of Pathology, Seattle Children’s Hospital, Seattle, Washington.
Diffuse ventricular thickening is often attributed to hypertrophic cardiomyopathy (HCM).1 We present a case of HCM with an unusual pathologic diagnosis. A 2-hour-old neonate presented with supraventricular tachycardia (SVT). Echocardiography demonstrated severe biventricular thickening with no outflow tract obstruction and normal function. Within 2 weeks, she developed low cardiac output with left ventricular outflow tract obstruction (3.7 m/s), and a doubling of interventricular septal wall thickness (diastolic dimension 2.02 cm, z-score ¼ 24.7, previously 1.1 cm, z-score ¼ 10.7). Gene testing was negative for Noonan syndrome and sarcomeric hypertrophic cardiomyopathy (HCM), as was screening for inborn errors of
2. Meyns B, Klotz S, Simon A, et al. Proof of concept: hemodynamic response to long-term partial ventricular support with the synergy pocket micro-pump. J Am Coll Cardiol 2009;54:79-86. 3. Meyns BP, Simon A, Klotz S, et al. Clinical benefits of partial circulatory support in New York Heart Association class IIIB and early class IV patients. Eur J Cardiothorac Surg 2011;39:693-8. 4. Sainte S, Gewillig M, Droogne W, et al. Explantation of a CircuLite left ventricular assist device without removal of the inflow cannula: how to do it? Interact Cardiovasc Thorac Surg 2013, http://dx.doi.org/10.1093/ icvts/ivt488: [E-pub ahead of print]. 5. Schmack B, Gorenflo M, Rengier F, Ruhparwar A. Extempore interventional closure of a broken CircuLite Synergy micropump inflow graft defect. J Heart Lung Transplant 2013;32:1140-1.
metabolism. Clinical examination was negative for features of tuberous sclerosis complex (TSC). Abdominal and brain magnetic resonance images were normal. The patient had recurrent hemodynamically significant episodes of SVT that worsened despite multiple antiarrhythmic medications. Intracardiac electrophysiology study revealed a retrograde-conducting, right-sided accessory pathway, which was ablated successfully. An intermittently conducting, concealed, left-sided pathway was not ablated. Due to complete atrioventricular block, she received a permanent dual-chamber pacemaker 10 days later. Shortly thereafter, she developed periods of pacemaker-mediated tachycardia, where ventricular pacing was conducted retrograde via accessory pathway to the atrium, tracked by the device, and then re-propagated back to the ventricle. To prevent this, the device was programmed to asynchronous (VVI) pacing. The patient then had cardiovascular collapse requiring extracorporeal cardiopulmonary resuscitation (ECPR), followed by progressive ventricular dysfunction, and was listed for transplantation. She developed new pre-excitation
Case Anecdotes, Comments and Opinions
453
Figure 1 (A) Gross and microscopic pathology of diffuse rhabdomyomatosis. (A) A formalin-fixed transverse section of the right and left ventricles, just apical to the atrioventricular valves, demonstrates biventricular mural hypertrophy and mottled regions of deeper tan and a pale myocardium. (B) A montage of photomicrographs from the left ventricle illustrates replacement of large, irregularly shaped zones in the myocardium by rhabdomyoma cells, which have abundant clear cytoplasms. (C) At higher magnification, enlargement and central vacuolization characterizes the rhabdomyoma cells, in contrast to adjacent histologically normal (nl) cardiac myocytes. (D) Rare “spider cells” (arrow), with central nuclei, large peripheral cytoplasmic vacuoles and intervacuolar eosinophilic cytoplasm, were present in the rhabdomyoma. (B) Rhabdomyoma involvement in the cardiac conduction system. A trichrome-stained longitudinal section through the right atrium and ventricle demonstrates the atrioventricular bundle (AVB), most of which is replaced by rhadomyoma. The inset shows a portion of the AVB (dashed rectangle) at higher magnification. More extensive atrial involvement was present in other sections.
with a surface delta wave pattern consistent with a left-sided accessory pathway, which resulted in 1:1 conducted sinus rhythm, increased ventricular rate and worse ventricular dysfunction. The pacemaker was reprogrammed to function as a resynchronization pacemaker by delivering right ventricular pacing simultaneous with left-sided pre-excitation, which normalized her QRS complex. Left ventricular outflow tract obstruction resolved, but posterior wall and interventricular septal thicknesses fluctuated. Severe heart failure was managed with inotropes and mechanical ventilation until orthotopic heart transplantation at 4 months of age. The patient’s explanted heart weighed 157 g (normal range 30 ⫾ 6 g) and demonstrated biventricular hypertrophy (Figure 1A). The heart was infiltrated by irregularly shaped lesions that replaced the majority of her myocardium and
portions of the conduction system (Figure 1B). Large myocytes with vacuolated cytoplasms and rare “spider cells” comprised the lesions. This pathology has been termed “diffuse rhabdomyomatosis” in 4 earlier reports, all with similar features to those seen in the patient described here.2 Diffuse rhabdomyomatosis is associated with refractory arrhythmias and heart failure in infancy. The infiltrative nature of diffuse rhabdomyomatosis is unlike the discrete cardiac rhabdomyomas characteristic of TSC. Although the common non-infiltrative rhabdomyomas associated with TSC have a benign course and often regress in early childhood,3 the natural history of diffuse rhabdomyomatosis is quite different.2 All children described in earlier reports died, yet none with other signs of TSC. Because it is possible that other features of TSC may have arisen later had
454
The Journal of Heart and Lung Transplantation, Vol 33, No 4, April 2014
these patients survived,3 the patient described in this study will be followed by a medical geneticist. SVT is the most common arrhythmia with cardiac tumors in the neonatal period, and rhabdomyoma can be associated with ventricular pre-excitation.4 Evolution of inconsistent arrhythmia types suggests that the patient’s re-entrant tachycardia was not mediated by an embryonic accessory pathway. Destruction of the conduction system has been described in diffuse rhabdomyomatosis,5 and likely explains the unusual progression of this patient’s arrhythmias. Analogous alternate routes of conduction have been described in glycogen-storage disease, whereby diffuse myocardial infiltration may connect atrial and ventricular myocardium, resulting in pre-excitation. The differential diagnosis for infantile HCM includes primary sarcomeric defects, infiltrative cardiomyopathies with diagnosable biochemical perturbations, and syndromic cardiomyopathies. However, the presence of refractory arrhythmias and fluctuating wall thickness changes in a patient with diffuse ventricular thickening may indicate an alternative diagnoses, such as diffuse rhabdomyomatosis. This patient’s clinical course was atypical for sarcomeric HCM. Her early, severe and rapid progression to heart failure, recalcitrant SVT, and evolving arrhythmias were clues to a diagnosis other than HCM, which may have changed our approach to management. If diffuse rhabdomyomatosis was suspected and confirmed by biopsy, an electrophysiology study with the potential for decompensation would not have been pursued
Intraoperative transesophageal echocardiographic guidance of total artificial heart implantation Nowell M. Fine, MD,a Radha S. Gopalan, MD,b Francisco A. Arabia, MD,c Sudhir S. Kushwaha, MD,a and Krishnaswamy Chandrasekaran, MDa,b From the aDivision of Cardiovascular Diseases, Department of Medicine, Mayo Clinic, Rochester, Minnesota; b Division of Cardiovascular Diseases, Department of Medicine, Mayo Clinic, Scottsdale, Arizona; and the cDivision of Cardiovascular Surgery, Department of Surgery, Cedars-Sinai Medical Center, Los Angeles, California
For advanced heart failure patients who are candidates for mechanical circulatory support (MCS) but are at increased risk for poor outcomes after left ventricular assist device implantation, the total artificial heart (TAH) has become an important therapeutic option.1–3 The SynCardia TAH (SynCardia Systems Inc, Tucson, AZ) became the first TAH approved for use in the United States in 2004, and the number TAH-implanting centers is growing.2 Centers that perform echocardiography on MCS-supported patients have endeavored to characterize the signs of abnormal device function to deliver useful information in a timely manner. However, little is known about the role of intraoperative (IO) transesophageal echocardiography (TEE) during TAH implantation. In this report, we describe the role of IO-TEE during TAH implantation and discuss the utility and limitations of IO-TEE guidance.
aggressively. Given the natural history of diffuse rhabdomyomatosis, ablation could have been avoided and transplantation may have been pursued earlier, which is important because early transplant outcomes are directly related to the need for extracorporeal membrane oxygen (ECMO) support before transplantation.
Disclosure statement The authors have no conflicts of interest to disclose. We thank Lawrence Merritt, MD, for valuable input.
References 1. Coates TL, McGahan JP. Fetal cardiac rhabdomyomas presenting as diffuse myocardial thickening. J Ultrasound Med 1994;13:813-6. 2. Shrivastava S, Jacks JJ, White RS, et al. Diffuse rhabdomyomatosis of the heart. Arch Pathol Lab Med 1977;101:78-80. 3. Verhaaren HA, Venaaker O, De Wolf D, et al. Left ventricular outflow obstruction in rhabdomyoma of infancy: meta-analysis of the literature. J Pediatr 2003;143:258-63. 4. Gotlieb AI, Chan M, Palmer WH, et al. Ventricular preexcitation syndrome. Accessory left atrioventricular connection and rhabdomyomatous myocardial fibers. Arch Pathol Lab Med 1977;101:486-9. 5. Mandke JV, Kinare SG, Phatak AM. Congenital diffuse rhabdomyomatosis of the heart with biventricular outflow obstruction. Indian Heart J 1992;44:187-8.
Echocardiographic imaging of the TAH requires a thorough understanding of the device and its components, as well as the implantation procedure. During implantation, the ventricular portion of the recipient heart is excised, leaving only a rim of ventricular myocardium. The atria and their respective venous connections are left intact and form the atrial chambers of the TAH. The aortic and pulmonary roots are excised just above the aortic and pulmonary valves, leaving the distal ascending aorta and distal main pulmonary artery (PA) intact. The SynCardia TAH unit has 2 separate pneumatic pumping chambers, representing the left and right ventricles (the TAH components are illustrated in Supplementary Figure 1, available on the jhltonline.org Web site). The TAH also contains four Medtronic-Hall single-tilting disk valve prostheses (Medtronic-Hall, Medtronic, Minneapolis, MN) in each valvular position. Each pneumatic pumping chamber has an inlet valve representing the mitral and tricuspid valve and an outlet valve representing the aortic and pulmonary valve. The pneumatic pumping chambers are sutured to the rim of the ventricular myocardium adjoining the atrioven tricular groove. The outlet valves are connected to the retained native ascending aorta and PA, respectively, by a conduit. The diaphragms within each pumping chamber are pneumatically driven by an external driver that is connected by left and right drivelines tunneled extraperitoneally through the abdominal wall. The retention of both atria provide for an excellent imaging window of the TAH from the middle and upper esophageal IO-TEE imaging windows. Figure 1 shows IO-TEE images
