CASE REPORT
European Journal of Cardio-Thoracic Surgery 46 (2014) 743–744 doi:10.1093/ejcts/ezt651 Advance Access publication 21 January 2014
Acute tamponade of the left paracorporeal pump house due to membrane defect in a patient with a Berlin Heart EXCOR© biventricular assist device Sebastian Völza,*, Michael Holmberga, Bengt Redforsb and Göran Dellgrenc a b c
Department of Cardiology, Sahlgrenska University Hospital, Gothenburg, Sweden Department of Cardiothoracic Anesthesia and Intensive Care, Sahlgrenska University Hospital, Gothenburg, Sweden Department of Cardiothoracic Surgery, Sahlgrenska University Hospital, Gothenburg, Sweden
* Corresponding author. Department of Cardiology, Sahlgrenska University Hospital, 4 Bruna straket, 41345 Gothenburg, Sweden. Tel: +46-31-34200; e-mail: [email protected] (S. Völz). Received 1 October 2013; received in revised form 7 December 2013; accepted 17 December 2013
Abstract We report a case of acute tamponade of the left paracorporeal pump house in a patient supported by a Berlin Heart EXCOR biventricular assist device (BiVAD) caused by mechanical defect in the membrane of the arterial chamber. A 36-year old male was admitted for composite graft surgery due to a large aortic regurgitation and consecutive heart failure, decompensated postoperatively and was rescued by with an extracorporeal membrane oxygenation (ECMO) device. He was accepted for heart transplantation, and a BiVAD (Berlin Heart EXCOR) was implanted as bridge-to-transplantation. Two months after discharge, he experienced dyspnoea and received error signals from his BiVAD. Relatives released him from his BiVAD companion driver, connected him to the hand pump and transported him to our institution. On arrival, he was in cardiogenic shock and was stabilized by ECMO. Inspection of the arterial chamber revealed a wear hole and delamination of the diaphragm, which had led to a tamponade by air insufflation into the three-layer membrane. New BiVAD paracorporeal pumps were connected, and the patient was subsequently successfully transplanted. The case depicts the difficulty of diagnosis in this specific patient setting. Despite transparent design of the BiVAD chambers, the development of a chamber tamponade remained undetected until explantation of the system.
INTRODUCTION Ventricular assist devices prolong patient survival, but are commonly associated with complications such as infection, bleeding and thromboembolic events [1]. Mechanical defects within the pump system are common complications, but have rarely been published in scientific literature. The Berlin Heart Excor (Berlin Heart AG, Berlin, Germany) biventricular assist device (BiVAD) is a pneumatically driven pulsatile pump system with transparent polyurethane membranes separating air and blood compartments. We report the case of an acute tamponade of the left paracorporeal pump house, in a 36-year old male supported by a Berlin Heart Excor biventricular assist device, caused by mechanical defect in the membrane of the arterial chamber.
CASE REPORT A 36-year old male patient presented with a 2-month history of dyspnoea and was admitted to the cardiac care unit of Sahlgrenska University Hospital in Gothenburg, Sweden. He was diagnosed with severe aortic regurgitation, a dilated ascending aorta and heart failure with left ventricular end-diastolic volume
of 335 ml and an ejection fraction of 21%. He was operated with a composite graft, and initially showed a fairly good recovery. Ten days after surgery, he developed atrial fibrillation with a ventricular rate of 160 bpm and subsequently developed cardiogenic shock and circulatory arrest. He was initially treated with mechanical heart compressions (LUCAS©, Jolife, Lund, Sweden) and rescued with extracorporeal membrane oxygenation (ECMO). He was accepted for heart transplantation, and a BiVAD (Berlin Heart EXCOR©) was implanted as bridge-to-transplantation due to severe biventricular failure with no recovery on ECMO. In addition, his mechanical aortic valve was closed with a membrane. Two months after discharge, the patient noticed a change in the clicking sound from his BiVAD. A few hours later, he experienced sudden onset of dyspnoea and received low flow error signals from his BiVAD. Relatives released him from his BiVAD companion driver, connected him to the hand pump and transported him to our institution. On arrival, he was in cardiogenic shock and showed signs of pulmonary oedema. Persistent attempts to hand pump both pump houses at the same time led only to clinical deterioration and a rapid decrease in arterial oxygen saturation. He was therefore transferred to the operation room, and detachment of the right ventricular pump house resulted in instantaneous improvement of the patient’s pulmonary oedema. The patient was
© The Author 2014. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.
CASE REPORT
Keywords: Severe heart failure • Biventricular assist device • Mechanical complication
744
S. Völz et al. / European Journal of Cardio-Thoracic Surgery
Figure 1: (Left) Paracorporeal pump house with an intact membrane. (Right) Delamination of the diaphragm of the left ventricular pump house. (Dotted lines depict the borders of the membranes, corresponding schematic illustration below.)
then connected to veno-arterial ECMO using the right atrial and the aortic cannula, the former being Y-linked to the left ventricular apex cannula in order to achieve sufficient volume unloading of the left ventricle. After being haemodynamically stabilized, the patient underwent computer tomography (CT), which showed no signs of left ventricular thrombus or pulmonary embolism, thereby confirming similar findings from echocardiography. Inspection of the explanted arterial chamber revealed a wear hole and delamination of the diaphragm by air insufflation into the three-layered membrane. The defect diaphragm had taken the shape of a distended balloon now, bulging into both blood and air chamber, thereby causing a functional pump house air tamponade (Fig. 1). Having excluding ventricular thrombus formation, the patient was converted from ECMO back to BiVAD again, using all four cannulas reconnected to short-term centrifugal pumps (ROTAFLOW©, Maquet Cardiopulmonary AG, Hirrlingen, Germany). After 1 week of centrifugal pump support, the patient completely recovered with no neurological sequlae, and new BiVAD paracorporeal Berlin Excor pumps were connected to the previously placed cannulas. The patient was subsequently successfully transplanted with a successful outcome after another month of support.
reported [2]. To our knowledge, this is the first case, in the literature, of an acute left ventricular pump house tamponade in a patient supported by a Berlin Heart Excor biventricular assist device caused by delamination of the three-layered membrane of the pump house. A wear hole of the membrane layer adjacent to the air chamber and consecutive air insufflation into the three layers of the diaphragm caused severe impairment of membrane movement, leading to an insufficient unloading of the left ventricular system and cardiogenic shock. Simultaneous hand pumping of both pump houses only increased pulmonary pressure by increasing left ventricular preload, aggravating the patients’ pulmonary oedema. The case depicts the urgency and difficulty of diagnosis in this specific patient setting. Despite the transparent design of the BiVAD chambers, membrane rupture and the development of a chamber tamponade could go undetected until explantation of the system. Clinicians working with end-stage heart failure and ventricular assist devices should be aware of the possibility of such a mechanical complication. According to company information, a case of membrane rupture had been observed once, and neither specific data on the membrane defect nor clinical data were available. In addition, the case underlines the importance of informing and educating both patients and their relatives to be able to act adequately in case of emergency, as described in our case. If the patient had acted more actively as the sound from his BiVAD changed, it would have been possible to intervene before membrane delamination had caused a near total pump house tamponade. On the other hand, without the relatives’ quick and decisive action, our patient’s prognosis would have been significantly worse. Finally, ECMO support gave great benefit not just once, but twice during the patients stay at our hospital. We also recognized the great benefit of having four large cannulas in a situation like this, allowing different settings of short-term mechanical circulatory support, without the need for further surgery in the emergency situation. The patient could effectively be stabilized, and physicians in charge of care were given time to reflect upon differential diagnosis and consider effective treatment options.
Funding This research received no grant from any funding agency in the public, commercial or not-for-profit sectors. Conflict of interest: none declared.
DISCUSSION REFERENCES With the rise of long-term mechanical support devices in endstage heart failure, complication management has become increasingly important. Patients with BiVAD are more prone to suffer from adverse events such as bleeding and infection than those with left ventricular assist device (LVAD) support only [1]. There is a variety of different ventricular assist devices available, and mechanical complications in certain LVAD models have been
[1] Cleveland JC, Naftel DC, Reece TB, Murray M, Antaki J, Pagani FD et al. Survival after biventricular assist device implantation: an analysis of the Interagency Registry for Mechanically Assisted Circulatory Support database. J Heart Lung Transplant 2011;30:862–9. [2] Potapov EV, Kaufmann F, Stepanenko A, Hening E, Vierecke J, Löw A et al. Pump exchange for cable damage in patients supported with HeartMate II left ventricular assist device. ASAIO J 2012;59:37–40.
European Journal of Cardio-Thoracic Surgery 46 (2014) 743–744 doi:10.1093/ejcts/ezt651 Advance Access publication 21 January 2014
Acute tamponade of the left paracorporeal pump house due to membrane defect in a patient with a Berlin Heart EXCOR© biventricular assist device Sebastian Völza,*, Michael Holmberga, Bengt Redforsb and Göran Dellgrenc a b c
Department of Cardiology, Sahlgrenska University Hospital, Gothenburg, Sweden Department of Cardiothoracic Anesthesia and Intensive Care, Sahlgrenska University Hospital, Gothenburg, Sweden Department of Cardiothoracic Surgery, Sahlgrenska University Hospital, Gothenburg, Sweden
* Corresponding author. Department of Cardiology, Sahlgrenska University Hospital, 4 Bruna straket, 41345 Gothenburg, Sweden. Tel: +46-31-34200; e-mail: [email protected] (S. Völz). Received 1 October 2013; received in revised form 7 December 2013; accepted 17 December 2013
Abstract We report a case of acute tamponade of the left paracorporeal pump house in a patient supported by a Berlin Heart EXCOR biventricular assist device (BiVAD) caused by mechanical defect in the membrane of the arterial chamber. A 36-year old male was admitted for composite graft surgery due to a large aortic regurgitation and consecutive heart failure, decompensated postoperatively and was rescued by with an extracorporeal membrane oxygenation (ECMO) device. He was accepted for heart transplantation, and a BiVAD (Berlin Heart EXCOR) was implanted as bridge-to-transplantation. Two months after discharge, he experienced dyspnoea and received error signals from his BiVAD. Relatives released him from his BiVAD companion driver, connected him to the hand pump and transported him to our institution. On arrival, he was in cardiogenic shock and was stabilized by ECMO. Inspection of the arterial chamber revealed a wear hole and delamination of the diaphragm, which had led to a tamponade by air insufflation into the three-layer membrane. New BiVAD paracorporeal pumps were connected, and the patient was subsequently successfully transplanted. The case depicts the difficulty of diagnosis in this specific patient setting. Despite transparent design of the BiVAD chambers, the development of a chamber tamponade remained undetected until explantation of the system.
INTRODUCTION Ventricular assist devices prolong patient survival, but are commonly associated with complications such as infection, bleeding and thromboembolic events [1]. Mechanical defects within the pump system are common complications, but have rarely been published in scientific literature. The Berlin Heart Excor (Berlin Heart AG, Berlin, Germany) biventricular assist device (BiVAD) is a pneumatically driven pulsatile pump system with transparent polyurethane membranes separating air and blood compartments. We report the case of an acute tamponade of the left paracorporeal pump house, in a 36-year old male supported by a Berlin Heart Excor biventricular assist device, caused by mechanical defect in the membrane of the arterial chamber.
CASE REPORT A 36-year old male patient presented with a 2-month history of dyspnoea and was admitted to the cardiac care unit of Sahlgrenska University Hospital in Gothenburg, Sweden. He was diagnosed with severe aortic regurgitation, a dilated ascending aorta and heart failure with left ventricular end-diastolic volume
of 335 ml and an ejection fraction of 21%. He was operated with a composite graft, and initially showed a fairly good recovery. Ten days after surgery, he developed atrial fibrillation with a ventricular rate of 160 bpm and subsequently developed cardiogenic shock and circulatory arrest. He was initially treated with mechanical heart compressions (LUCAS©, Jolife, Lund, Sweden) and rescued with extracorporeal membrane oxygenation (ECMO). He was accepted for heart transplantation, and a BiVAD (Berlin Heart EXCOR©) was implanted as bridge-to-transplantation due to severe biventricular failure with no recovery on ECMO. In addition, his mechanical aortic valve was closed with a membrane. Two months after discharge, the patient noticed a change in the clicking sound from his BiVAD. A few hours later, he experienced sudden onset of dyspnoea and received low flow error signals from his BiVAD. Relatives released him from his BiVAD companion driver, connected him to the hand pump and transported him to our institution. On arrival, he was in cardiogenic shock and showed signs of pulmonary oedema. Persistent attempts to hand pump both pump houses at the same time led only to clinical deterioration and a rapid decrease in arterial oxygen saturation. He was therefore transferred to the operation room, and detachment of the right ventricular pump house resulted in instantaneous improvement of the patient’s pulmonary oedema. The patient was
© The Author 2014. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.
CASE REPORT
Keywords: Severe heart failure • Biventricular assist device • Mechanical complication
744
S. Völz et al. / European Journal of Cardio-Thoracic Surgery
Figure 1: (Left) Paracorporeal pump house with an intact membrane. (Right) Delamination of the diaphragm of the left ventricular pump house. (Dotted lines depict the borders of the membranes, corresponding schematic illustration below.)
then connected to veno-arterial ECMO using the right atrial and the aortic cannula, the former being Y-linked to the left ventricular apex cannula in order to achieve sufficient volume unloading of the left ventricle. After being haemodynamically stabilized, the patient underwent computer tomography (CT), which showed no signs of left ventricular thrombus or pulmonary embolism, thereby confirming similar findings from echocardiography. Inspection of the explanted arterial chamber revealed a wear hole and delamination of the diaphragm by air insufflation into the three-layered membrane. The defect diaphragm had taken the shape of a distended balloon now, bulging into both blood and air chamber, thereby causing a functional pump house air tamponade (Fig. 1). Having excluding ventricular thrombus formation, the patient was converted from ECMO back to BiVAD again, using all four cannulas reconnected to short-term centrifugal pumps (ROTAFLOW©, Maquet Cardiopulmonary AG, Hirrlingen, Germany). After 1 week of centrifugal pump support, the patient completely recovered with no neurological sequlae, and new BiVAD paracorporeal Berlin Excor pumps were connected to the previously placed cannulas. The patient was subsequently successfully transplanted with a successful outcome after another month of support.
reported [2]. To our knowledge, this is the first case, in the literature, of an acute left ventricular pump house tamponade in a patient supported by a Berlin Heart Excor biventricular assist device caused by delamination of the three-layered membrane of the pump house. A wear hole of the membrane layer adjacent to the air chamber and consecutive air insufflation into the three layers of the diaphragm caused severe impairment of membrane movement, leading to an insufficient unloading of the left ventricular system and cardiogenic shock. Simultaneous hand pumping of both pump houses only increased pulmonary pressure by increasing left ventricular preload, aggravating the patients’ pulmonary oedema. The case depicts the urgency and difficulty of diagnosis in this specific patient setting. Despite the transparent design of the BiVAD chambers, membrane rupture and the development of a chamber tamponade could go undetected until explantation of the system. Clinicians working with end-stage heart failure and ventricular assist devices should be aware of the possibility of such a mechanical complication. According to company information, a case of membrane rupture had been observed once, and neither specific data on the membrane defect nor clinical data were available. In addition, the case underlines the importance of informing and educating both patients and their relatives to be able to act adequately in case of emergency, as described in our case. If the patient had acted more actively as the sound from his BiVAD changed, it would have been possible to intervene before membrane delamination had caused a near total pump house tamponade. On the other hand, without the relatives’ quick and decisive action, our patient’s prognosis would have been significantly worse. Finally, ECMO support gave great benefit not just once, but twice during the patients stay at our hospital. We also recognized the great benefit of having four large cannulas in a situation like this, allowing different settings of short-term mechanical circulatory support, without the need for further surgery in the emergency situation. The patient could effectively be stabilized, and physicians in charge of care were given time to reflect upon differential diagnosis and consider effective treatment options.
Funding This research received no grant from any funding agency in the public, commercial or not-for-profit sectors. Conflict of interest: none declared.
DISCUSSION REFERENCES With the rise of long-term mechanical support devices in endstage heart failure, complication management has become increasingly important. Patients with BiVAD are more prone to suffer from adverse events such as bleeding and infection than those with left ventricular assist device (LVAD) support only [1]. There is a variety of different ventricular assist devices available, and mechanical complications in certain LVAD models have been
[1] Cleveland JC, Naftel DC, Reece TB, Murray M, Antaki J, Pagani FD et al. Survival after biventricular assist device implantation: an analysis of the Interagency Registry for Mechanically Assisted Circulatory Support database. J Heart Lung Transplant 2011;30:862–9. [2] Potapov EV, Kaufmann F, Stepanenko A, Hening E, Vierecke J, Löw A et al. Pump exchange for cable damage in patients supported with HeartMate II left ventricular assist device. ASAIO J 2012;59:37–40.
