Abstract WP403: Trends and Predictors of Intracranial Hemorrhage in Patients With Advanced Heart Failure on Left Ventricular Assist Device From 2005 to 2014 in the U.S

Introduction: Left ventricular assist device (LVAD) is known to extend survival in patients with advanced heart failure but it is associated with intracranial cranial hemorrhage (ICH). In the last decade, the use of LVAD substantially increased along with advances in LVAD technology, but there is limited data regarding the trends of ICH risk and predictors in patients with LVAD.

Methods: We included the patients aged≥18 years with primary diagnosis of LVAD hospitalized in the US from 2005 to 2014 using the National Inpatient Sample. We computed the survey weighted percentages with ICH across the 10-year study period and assessed whether the proportions changed over time. Predictors of ICH were evaluated using the multivariable logistic regression model. All analyses were appropriately adjusted for the survey design variables to account for the complex survey design.

Results: Of 33,246 hospitalizations, 568 (1.7%) had ICH. The number of LVAD placement has increased from 873 in year 2005 to 5,175 in year 2014. However, the risk of ICH remained largely unchanged from 1.7% to 2.3% (linear trend: p=0.604). The adjusted odds of ICH was increased with the presence one of the following variables: female sex (odds ratio [OR]: 1.58, 95% confidence interval [CI] 1.03-2.43), history of ischemic stroke (OR: 3.13, 95% CI 1.86-5.28), and Charlson Comorbidity Index (CCI) of ≥3 (OR: 77.40, 95% CI 10.03-597.60).

Conclusions: Despite advances in LVAD technology and its increased use in patients with advanced heart failure, the risk of ICH has remained relatively unchanged. High CCI and history of ischemic stroke were associated with higher odds of ICH in patients with LVAD. With the advent of magnetically levitated centrifugal-flow LVAD, future trend of ICH may change and further research efforts are needed to prevent ICH in patients with LVAD.

Use of Omental Flap for Treating Cardiocutaneous Fistula After Ventricular Aneurysm Repair

Infection of an endoventricular patch used for left ventricular aneurysm repair with formation of cardiocutaneous fistula is a rare but potentially serious complication. We report an adult patient who developed a cardiocutaneous fistula 1 year after repair of a third left ventricular aneurysm. The patient was successfully treated with a redo operation using a bovine pericardial patch with omental flap coverage. He is alive and well 10 years later.

Electric shock-induced cardiac injuries requiring surgical intervention: Case series and a brief review

BACKGROUND

Electric shock-induced cardiac injuries, such as myocardial infarction, thrombosis, and dissection, are rare. Few cases have been previously reported. The right coronary artery is most often affected because of its proximity to the chest wall.

AIMS

To study the extend of electrical injuries on cardiac tissues and its surgical management.

MATERIALS AND METHODS

We conducted a retrospective study on our patients in the last five years, looking for cardiac electrical injuries treated surgically in our department, we identified three cases.

RESULT

Our three-case series, reported herein, showed that multiple cardiac tissues are susceptible to electrical injuries, specifically the left coronary artery, inferior vena cava, and right ventricular free wall. In our series, the first patient was a 32-year-old man with triple vessel thrombosis and dissection who survived the electric shock. The second patient was a 23-year-old man who had an inferior vena cava burn and bruising; his heart was used for transplantation. After the transplant, the recipient had a left coronary artery dissection and underwent coronary artery bypass grafting. The third patient was a 30-year-old man (potential heart donor) who had a hematoma of the right ventricular free wall, possible coronary artery dissection, inferior vena cava bruising, and tissue damage. His heart was not used for transplant because of quality concerns.

CONCLUSION

We recommend that any person who sustains high voltage (500 V or more) electric shock should be evaluated carefully in the emergency department, including with echocardiography and cardiac catheterization, if indicated, to determine the extent of the injury and the viability of the heart, for patients who do not survive as a donor organ.

Successful lung transplantation from a donor with lung and ovarian masses

Declining a donor when there is a reasonable possibility that the abnormality on chest imaging could be benign carries the risk of losing out on potentially usable lungs in an already parched landscape of donor organ availability. Cautiously aggressive attitudes to acceptance of borderline donors can help bridge the significant discrepancy that exists between the demand and availability of donor organs. Herein, we present a case highlighting successful bilateral lung transplantation from a relatively imperfect donor.

Incidence, Management, and Outcomes of Chylothorax after Lung Transplantation: A Single-center Experience

Background

The objective of this study was to determine the incidence and outcomes of chylothorax after lung transplantation.

Methods

We conducted a retrospective review of our institutional lung transplant registry of 504 adult transplantations done from 2001 to 2015 and identified seven patients (1.38%) with chylothorax. Electronic health records were then analyzed to determine demographics, indications for surgery, management, and outcomes. Survival curves were plotted using the Kaplan-Meier method.

Results

Chylothorax presented in the first week in four (62.5%) patients, and approximately one month later in the remaining three. Nonsurgical management was initially attempted in all patients and succeeded in three (42.9%). Elective surgical ligation of the thoracic duct (LTD) was successful in two (66.7%) out of three patients in whom it was performed. One patient required emergent reoperation for clamshell thoracotomy dehiscence from severe chylothorax. Thoracic duct embolization was attempted but unsuccessful in two patients. Subsequently, one of these patients received a peritoneal-venous shunt and the other underwent LTD. Chylothorax permanently resolved in six patients (85.7%). There were no mortalities directly related to chylothorax. The median time to resolution was 11 days (range: 7-60). The mean survival in months for chylothorax patients was 29.2 (SE 3.1) and 78.2 (SE 2.9) for the remaining patients (p = 0.37). The median survival was not reached for the chylothorax group and was 71.8 months (95% CI: 58.0-83.9) for the rest.

Conclusion

Chylothorax is rare after lung transplantation but can lead to major comorbidities and prolonged hospital stay. In our experience, nonsurgical management was successful in up to 40% of patients. LTD should be considered in those who fail conservative management. 

Triple bridge of mechanical circulatory support to heart transplantation listing: A case report

A 60-year-old male patient presented to an outside hospital with severe cardiogenic shock. A triple bridge of mechanical circulatory support was utilized to transition him to heart transplantation listing. Initially, coronary artery disease was percutaneously treated and Impella 2.5 was used as mechanical circulatory support for 5 days followed by the second Impella 2.5 for 4 days. Veno-arterial extracorporeal membrane oxygenation support was deployed for 16 days. This was exchanged for HeartWare ventricular assist device support as the third stage of mechanical circulatory support to heart transplantation listing. The patient experienced acute renal failure which was managed by continuous renal replacement therapy then intermittent hemodialysis with eventual complete recovery of the renal function. He was discharged home 56 days after HeartWare ventricular assist device implantation with stable hemodynamic, intact neurologic status and fully recovered renal function. Currently, the patient is listed for heart transplantation.

Ambulation With Femoral Arterial Cannulation Can Be Safely Performed on Venoarterial Extracorporeal Membrane Oxygenation

BACKGROUND

Venoarterial extracorporeal membrane oxygenation (VA-ECMO) support can be associated with significant deconditioning due to the requirement for strict bedrest as a result of femoral arterial cannulation. To address this issue, we evaluated our experience with ambulation in patients with peripheral femoral cannulation for VA-ECMO.

METHODS

All patients that were peripherally cannulated for VA-ECMO over a 2-year period were retrospectively reviewed. Patients that ambulated at least once while supported with VA-ECMO were included in the analysis. The primary outcomes were safety and feasibility of ambulation, defined as the absence of major bleeding, vascular, or decannulation events.

RESULTS

Of 104 patients placed on VA-ECMO, 15 ambulated with a femoral arterial cannula. Forty-six percent of patients were placed on VA-ECMO for decompensated heart failure, and 54% for massive pulmonary embolism. Twenty-seven percent of patients were cannulated during active cardiopulmonary resuscitation. The median length of time from cannulation to out of bed was 3 (range, 0 to 26) days. The median length of time from cannulation to initial ambulation was 4 (range, 1 to 42) days. The median distance of the first postcannulation walk was 300 feet. Neither flow nor speed decreased during or after ambulation. There were no major bleeding events, vascular complications, or decannulation events associated with ambulation. The median intensive care unit length of stay and hospital length of stay were 12 and 21 days, respectively. One-year survival was 100% for ambulating patients.

CONCLUSIONS

Ambulating patients supported with VA-ECMO, despite femoral arterial cannulation, appears feasible and safe in carefully selected patients.

Oxidative stress induced modulation of platelet integrin α2bβ3 expression and shedding may predict the risk of major bleeding in heart failure patients supported by continuous flow left ventricular assist devices

INTRODUCTION

Oxidative stress and platelet integrin α2bβ3 plays important role in the process of hemostasis and thrombosis. We hypothesized that device-induced patient specific oxidative stress and integrin α2bβ3 shedding may be linked to major bleeding complication (MBC) in heart failure (HF) patients supported by continuous flow left ventricular assist devices (CF-LVADs).

MATERIALS AND METHODS

We recruited 47patients implanted with CF-LVADs and 15 healthy volunteers. Fourteen patients developed MBC (bleeder group) within one month after implantation while others were considered non-bleeder group (n=33). Oxidative stresses were evaluated by measuring reactive oxygen species (ROS) in platelets, superoxide dismutase (SOD) activity, total antioxidant capacity (TAC) and oxidized low density lipoprotein (oxLDL). Assessments of α2bβ3 were carried out using flow cytometry and ELISA.

RESULTS

Biomarkers of oxidative stress and α2bβ3 shedding (decreased surface expression and higher plasma levels) were found to be preexisting condition in all HF patients prior to CF-LVAD implantation compared to the healthy volunteers. Significantly elevated levels of ROS and oxLDL; concomitant depletion of SOD and TAC; and α2bβ3 shedding were observed in the bleeder group temporarily in comparison to the non-bleeder group after CF-LVAD implantation. A significantly strong association between α2bβ3 shedding and biomarkers of oxidative stress was observed; suggesting a potential role of oxidative stress in platelet integrin shedding leading to MBC after CF-LVAD implantation. Moreover, a receiver operating characteristic (ROC) analysis indicated that the likelihood of MBC data from Integrin α2bβ3 shedding had a predictive power of MBC in CF-LVAD patients.

CONCLUSIONS

Oxidative stress might play a potential role in accelerating α2bβ3 shedding and platelet dysfunction, resulting in MBC in CF-LVAD patients. Integrin α2bβ3 shedding may be used to refine bleeding risk stratification in CF-LVAD patients.

Abstract 329: ST266 Attenuates Neointima Formation After Arterial Balloon Angioplasty in Rats

Objective: Post-angioplasty restenosis due to neointima formation has been attributed to the inflammatory response after acute endoluminal injury. ST266 (Noveome Biotherapeutics, Inc.) a novel secretome derived from proprietary GMP-cultured human Amnion-Derived Multipotent Progenitor (AMP) cells, has been shown to be anti-inflammatory and to promote wound healing. This study examined the therapeutic potential of ST266 in a rat arterial balloon angioplasty model.

Methods: Animals were randomly divided in the following groups (N=7): no-treatment (noTx), systemic ST266, systemic AMPs and local AMP implants. Neointima hyperplasia was induced in the iliac artery of Sprague-Dawley male rats using a 2F Fogarty embolectomy catheter. After surgery, animals in ST266 groups received 0.1, 0.5 or 1ml IV ST266 q.d. In the systemic AMP groups, single-dose (SD) of 0.5 million (M) or 1 M AMPs was injected via Inferior Vena Cava after the angioplasty. In AMP implant experiment 1 M, 5 M or 20 M AMPs were implanted in 300 μL Matrigel (MTG) around the iliac artery after balloon angioplasty. 28 days after the surgery, the iliac arteries were removed for histologic analysis. Re-endothelialization index was measured 10 days after balloon angioplasty.

Results: 1ml ST266 decreased Neointima/Neointima+Media ratio (N/NM) compared to noTx group (0.34±0.01 vs 0.54±0.04 resp.; p =0.004). ST266 also decreased Luminal Stenosis (LS) compared to noTx group (18.18±1.86 vs 39.23±5.75%; p =0.008). SD 1 M AMPs decreased LS compared to noTx group (39.23±5.75 vs 19.50±5.35%; p =0.033). Significant differences in N/NM were found between 20 M implanted AMPs and noTx group (0.35±0.02 vs 0.54±0.04 resp.; p =0.003) and the MTG-only group (0.53±0.05, p =0.007). 20 M implanted AMPs decreased the LS (16.78±2.47%) compared to both noTx (39.23±5.75%, p =0.001) and MTG-only groups (37.51±8.55%, p =0.016). 1ml ST266 significantly increased the re-endothelialization index 10 days after balloon angioplasty compared to noTx group (0.40±0.04 vs 0.14±0.037% resp., p =0.002).

Conclusion: ST266 reduces neointima formation and luminal stenosis and increases the re-endothelialization index after balloon angioplasty. Further research to elucidate the underlying mechanisms is ongoing.

Extracorporeal Lung Support as a Bridge to Airway Stenting and Radiotherapy for Airway-Obstructing Pancoast Tumor

Venovenous (V-V) extracorporeal membrane oxygenation (ECMO) is used for respiratory failure that is suspected to be reversible (bridge to recovery), or as a bridge to lung transplantation. Patients with proximal airway obstruction due to endobronchial malignancy can develop acute respiratory failure, and may benefit from V-V ECMO as a bridge to airway intervention, further treatment, and eventual recovery. We describe a case of a superior sulcus tumor with tracheobronchial and superior vena cava invasion causing both respiratory failure and superior vena cava syndrome. This was treated successfully with V-V ECMO, bronchial stenting, and radiotherapy.

Mechanistic insight of platelet apoptosis leading to non-surgical bleeding among heart failure patients supported by continuous-flow left ventricular assist devices

Non-surgical bleeding (NSB) is the most common clinical complication in heart failure (HF) patients supported by continuous-flow left ventricular assist devices (CF-LVADs). In this study, oxidative stress and alteration of signal pathways leading to platelet apoptosis were investigated. Thirty-one HF patients supported by CF-LVADs were divided into bleeder (n = 12) and non-bleeder (n = 19) groups. Multiple blood samples were collected at pre-implant (baseline) and weekly up to 1-month post-implant. A single blood sample was collected from healthy subjects (reference). Production of reactive oxygen species (ROS) in platelets, total antioxidant capacity (TAC), oxidized low-density lipoproteins (oxLDL), expression of Bcl-2 and Bcl-xL, Bax and release of cytochrome c (Cyt.c), platelet mitochondrial membrane potential (Δψ _m), activation of caspases, gelsolin cleavage and platelet apoptosis were examined. Significantly elevated ROS, oxLDL and depleted TAC were evident in the bleeder group compared to non-bleeder group (p < 0.05). Platelet pro-survival proteins (Bcl-2, Bcl-xL) were significantly reduced in the bleeder group in comparison to the non-bleeder group (p < 0.05). Translocation of Bax into platelet mitochondria membrane and subsequent release of Cyt.c were more prevalent in the bleeder group. Platelet mitochondrial damage, activation of caspases, gelsolin cleavage, and ultimate platelet apoptosis in the bleeder group were observed. Oxidative stress and activation of both intrinsic and extrinsic pathways of platelet apoptosis may be linked to NSB in CF-LVAD patients. Additionally, biomarkers of oxidative stress, examination of pro-survivals and pro-apoptotic proteins in platelets, mitochondrial damage, caspase activation, and platelet apoptosis may be used to help identify HF patients at high risk of NSB post-implant.

Impact on postoperative bleeding and cost of recombinant activated factor VII in patients undergoing heart transplantation

Background:

Cardiac transplantation can be complicated by refractory hemorrhage particularly in cases where explantation of a ventricular assist device is necessary. Recombinant activated factor VII (rFVIIa) has been used to treat refractory bleeding in cardiac surgery patients, but little information is available on its efficacy or cost in heart transplant patients.

Methods:

Patients who had orthotopic heart transplantation between January 2009 and December 2014 at a single center were reviewed. Postoperative bleeding and the total costs of hemostatic therapies were compared between patients who received rFVIIa and those who did not. Propensity scores were created and used to control for the likelihood of receiving rFVIIa in order to reduce bias in our risk estimates.

Results:

Seventy-six patients underwent heart transplantation during the study period. Twenty-one patients (27.6%) received rFVIIa for refractory intraoperative bleeding. There was no difference in postoperative red blood cell transfusion, chest tube output, or surgical re-exploration between patients who received rFVIIa and those who did not, even after adjusting with the propensity score (P = 0.94, P = 0.60, and P = 0.10, respectively). The total cost for hemostatic therapies was significantly higher in the rFVIIa group (median $10,819 vs. $1,985; P < 0.0001). Subgroup analysis of patients who underwent redo-sternotomy with left ventricular assist device explantation did not show any benefit for rFVIIa either.

Conclusions:

In this relatively small cohort, rFVIIa use was not associated with decreased postoperative bleeding in patients undergoing heart transplantation; however, it led to significantly higher cost.

Thrombosis of the Right Internal Jugular Vein is Not a Contraindication to Ambulatory Veno-Venous Extracorporeal Membrane Oxygenation with a Bicaval Dual-Lumen, Single Cannula System

Background: Veno-venous extracorporeal membrane oxygenation (VV-ECMO) is an ever-emerging method of managing respiratory failure in patients who are refractory to conventional mechanical ventilatory support. An increasingly common method of cannulation involves placement of a bicaval dual-lumen, single cannula via the right internal jugular (IJ) vein. Thrombus in this vein has been considered a contraindication for cannula placement. Case report: A 45-year-old Hispanic male presented with bleomycin-induced respiratory failure resulting in acute respiratory distress syndrome (ARDS). Ambulatory VV-ECMO support was initiated, and during surgical cannula placement an occlusive thrombus was noted in the right IJ vein. A tract was dilated and the cannula was placed without any thromboembolic complications.Conclusion: This case demonstrates that cannulation for ambulatory VV-ECMO in the setting of an occlusive IJ thrombus can be safe and feasible.

Therapeutic plasma exchange in heart transplantation: role of coagulation assessment with thromboelastometry

Therapeutic plasma exchange (TPE) is a potentially life-saving procedure which effectively removes donor-specific human leukocyte antigen (HLA) antibodies from the bloodstream, allowing critically ill heart transplant recipients to receive a donor organ with less wait time, and reducing the risk of acute organ rejection. The bulk of coagulation factors is initially removed from the blood during TPE using albumin and is later replaced with allogeneic plasma. Coagulopathy may develop during TPE and then can persist due to intraoperative blood loss and hemodilution during surgery and cardiopulmonary bypass. We hereby describe the utility of rotational thromboelastometry to assess rapid coagulation changes during TPE and subsequent heart transplant (HT) surgery.

The use of extended criteria donors decreases one-year survival in high-risk lung recipients: A review of the United Network of Organ Sharing Database

OBJECTIVE

The study objective was to investigate the impact of matching donor quality to recipient severity on survival after lung transplant.

METHODS

By using the Organ Procurement and Transplantation Network/United Network for Organ Sharing dataset, we analyzed lung transplant recipients from May 4, 2005, to December 31, 2012. By using adjusted Cox regressions, we identified extended criteria donors as those who had 1 or more of the following: age 65 years or more, smoking history of 20 pack-years or more, diabetes mellitus, or African-American race. All other donors were considered standard donors. Recipients were categorized by lung allocation score: lung allocation score less than 70 and lung allocation score 70 or greater. Our primary outcome was 1-year survival after lung transplantation.

RESULTS

Of the 10,995 lung recipients, 3792 (34%) received extended criteria donor organs. Extended criteria donors were associated with an increased hazard of death (hazard ratio [HR], 1.41; 95% confidence interval [CI], 1.26-1.56; P < .001). One-year survival was 87% and 82% (P < .001) for recipients with a lung allocation score less than 70 and 80% and 72% (P = .017) for recipients with a lung allocation score 70 or greater who received standard donor and extended criteria donor organs, respectively. In Cox regression models, the hazard of death was increased for recipients with a lung allocation score less than 70 + extended criteria donor (HR, 1.42; 95% CI, 1.27-1.60; P < .001), recipients with a lung allocation score 70 or greater + standard donor (HR, 1.37; 95% CI, 1.10-1.71; P = .005), and was the highest for recipients with a lung allocation score 70 or greater + extended criteria donor (HR, 1.81; 95% CI, 1.40-2.33; P < .001) compared with recipients with a lung allocation score less than 70 + standard donor.

CONCLUSIONS

Extended criteria donors are associated with reduced 1-year survival, and recipients with a lung allocation score 70 or greater who receive extended criteria donor organs have the lowest survival.

Lung Donation After Controlled Circulatory Determination of Death: A Review of Current Practices and Outcomes

BACKGROUND

Since the first reported series in 1995, transplantation of lungs recovered through donation after circulatory determination of death (DCDD) has steadily increased. In some European and Australian centers, controlled DCDD accounts for 15% to 30% of all transplanted lungs. Several transplant centers have reported early and midterm outcomes similar to those associated with the use of donors after brain death. Despite these encouraging reports, less than 2% of all lung transplants in the United States are performed using donors after circulatory determination of death.

METHODS

An electronic search from January 1990 to January 2014 was performed to identify series reporting lung transplant outcomes using controlled DCDD. Data from these publications were analyzed in terms of donor characteristics, donation after circulatory determination of death protocols, recipients' characteristics, and early and midterm outcomes.

RESULTS

Two hundred twenty-two DCDDs were transplanted into 225 recipients. The rate of primary graft dysfunction grade 3 ranged from 3% to 36%. The need for extracorporeal membrane oxygenation support after transplantation ranged from 0% to 18%. The average intensive care unit stay ranged from 4 to 8.5 days and the average hospital stay ranged from 14 to 35 days. Thirty-day mortality ranged from 0% to 11% and 1-year survival from 88% to 100%.

CONCLUSION

Under clinical protocols developed and strictly applied by several experienced lung transplant programs, lungs from controlled DCDD have produced outcomes very similar to those observed with brain death donors.