- Email: [email protected]
Heartmate II Inflow Cannula Migration Does Not Predict Late-Term Complications
S200
The Journal of Heart and Lung Transplantation, Vol 32, No 4S, April 2014
56% and 95%, 92%, 86% respectively. Pre- and peri-operative variables influencing the development of post-implant RD in this normal cohort were: history of atrial arrhythmia (OR 4.37 CI 1.10-17.32 p= 0.026), raised mean Right Atrial Pressure (mRAP / mmHg) (19.50 + 6.49 vs 14.66 + 5.88 p= 0.021), cardiopulmonary bypass time (CPB / min) 142.85+ 64.69 vs 110.59 + 34.96 p= 0.011), total length of surgery (hr) (6.91 + 3.12 vs 5.7 + 1.32 p= 0.026), intraoperative FFP (units) (6.09 +13.06 vs 2.70 + 2.04 p= 0.046) and Cryoprecipitate (units) ( 4.0 + 5.91 vs 1.77 + 2.36 p= 0.026) transfusion. Postoperative variables correlating with RD were Cryoprecipitate (2.83 + 5.42 vs 0.52 + 2.13 p= 0.011) and platelet (1.33 + 22.23 vs 0.4 + 0.85 p= 0.012) transfusions, days on post-op inotropes (45.23 + 113.33 vs 10.69 + 9.74 p= 0.022), length of ICU stay (days) (22.08 + 18.21 vs 12.88 + 10.67 p= 0.015) and re-exploration for bleeding (OR 4.73 CI 0.92 - 24.33 p= 0.046). Conclusion: Post VAD-implant RD in patients with normal pre-operative renal function confers significant morbidity and survival disadvantage. This study reinforces the need to better optimize pre-operative volume status, limit bypass and surgical times, reduce peri- and post operative blood product transfusions, and avoid re-exploration for bleeding. 5( 37) The Impact of Baseline Renal Dysfunction on Patient Outcomes after Implantation of Chronic Mechanical Circulatory Support Devices C. Anthony ,1 R. Lui,2 J. Sevastos,3 K. Dhital,1 E. Granger,1 C.S. Hayward,1 A. Jabbour,1 P.C. Jansz,1 A.M. Keogh,1 E. Kotlyar,1 D. Robson,1 P.S. Macdonald,1 P.M. Spratt.1 1Heart & Lung Transplant Unit, “St. Vincent’s Health Network, Sydney, Australia; 2St Vincent’s Hospital Clinical School, University of New South Wales, Sydney, Australia; 3Department of Renal Medicine, St. Vincent’s Health Network, Sydney, Australia. Purpose: To assess the impact of baseline renal dysfunction on morbidity and mortality after chronic mechanical circulatory support (MCS) implantation. Methods: Retrospective review of 101 consecutive MCS patients implanted between November 2006 and October 2013 (89 LVAD, 7 BiVAD and 5 TAH; M:F 77:24; mean age 49 +/- 15 years; Intermacs class I:II-III 27:74). eGFR (MDRD formula) on the day of implant was > 90 in 13, 60-89 in 38, 30-59 in 47 and < 30 ml/min/1.73m2 in 3 patients. Acute kidney injury (AKI) grade by RIFLE criteria (1) in the month prior to MCS implant was no injury (N) in 54, risk (R) in 20, injury (I) in 17 and failure (F) in 10 patients. Outcomes of the 3 patients with baseline eGFR < 30 ml/min/1.73m2 and the 10 patients with RIFLE F AKI (RF group) were compared with the remaining 88 patients (non-RF group). Results: Compared with the non-RF group, the RF group had increased requirement for post-MCS renal replacement therapy (62% vs 13%, p< 0.002) and length of stay (54 +/- 9 vs 38 +/- 2 days, p < 0.02). Actuarial survival at 6 and 12 months (Figure 1) was 59 +/- 14 and 49 +/- 15 % in the RF group versus 92 +/- 3 and 78 +/- 5% in the non-RF group (p < 0.01). Conclusion: Patients with baseline eGFR < 30 ml/min/1.73m2 or severe AKI (RIFLE F) in the month pre-MCS implant are at high risk of acute renal failure post-MCS implant. Morbidity is high and survival is poor in this group. In contrast, patients with lesser degrees of renal impairment have excellent post-MCS outcomes. Reference (1) Bellomo R, Ronco C, Kellum JA, et al. Crit Care, 2004, Vol. 8. R204-12.
5( 38) Assessment of the LVAD Inflow Cannula Position by Cardiac CT K. Ghafourian ,1 W.G. Weigold,1 S.M. Jani,1 D. Abramov,1 G. Ruiz,1 M. Hofmeyer,1 D.T. Majure,1 F.H. Sheikh,1 R.D. Bannerman,1 E.J. Molina,2 S.W. Boyce,2 S.S. Najjar,1 G. Weissman.1 1Cardiology, Medstar Washington Hospital Center, Washington, DC; 2Surgery, Medstar Washington Hospital Center, Washington, DC. Purpose: Position of the inflow cannula (IC) within the left ventricle may affect optimal function of the LVAD and contribute to the risk of complications. We evaluated the intraventricular position of the IC in Heartmate II (HM2) and Heartware (HW) LVADs. Methods: A single-center retrospective review of the most recent cardiac CT (CCT) of all continuous flow LVAD implants between 10/2006 and 9/2013 was performed. CT acquisitions were completed on a 64 or 256 slice platform using ECG gated helical technique. Measurements were performed in standard 2-chamber and short-axis views. Fisher’s exact and Wilcoxon-MannWhitney tests were used to determine statistical difference between groups. Results: A total of 195 patients underwent LVAD implants (101 HM2, 94 HW). At least one CCT was performed on 63 patients. Mean LV end diastolic diameter was 63 ± 11 mm. Apical tip of the IC was more frequently in contact with anterior wall in the HM2 patients (15/24, 62%) compared to HW pumps (5/38, 13%, p< 0.001). Basal tip did not abut the anterior wall in any patient. Septal wall contact was 25% vs. 5 % (p= 0.05) and lateral wall contact was 29% vs. 25% (p= 0.7) in HM2 and HW pumps, respectively. In the total population, the IC was angulated towards the mitral annulus plane (median 33 degrees, IQR 22, 46) and formed a 77-degree horizontal angle in the short axis (IQR 57, 95, figure 1). Angle of the IC was significantly different between HM2 and HW LVADs (table 1). Conclusion: Significant variation exists among patients and between two different types of continuous-flow LVAD with regards to intraventricular position of the inflow cannula. Clinical significance of these variations remains to be determined. Table 1.
Inflow cannula position within the ventricle in HM2 and HW LVADs.
Inflow Cannula Distance/Position (median, IQR)
Total (N= 63)
HM2 (N= 24)
HW (N= 39 )
P-value
16 (8,24)
12 (3,18)
18 (12,27)
0.008
IC tip to lateral wall 10 (0,16) (mm)
8 (0,10)
15 (3,18)
0.020
IC apical tip to anterior wall (mm)
14 (0,25)
0 (0,16)
18 (10,30)
< 0.001
IC basal tip to anterior wall (mm)
29 (20,39)
30 (17,40)
29 (23,38)
0.6
Angulation towards 33 (22,46) base (degree)
43 (35,47)
26 (10,44)
0.001
Angulation towards 77 (57,95) lateral wall (degree)
89 (80,120)
62 (52,86)
< 0.001
IC tip to septum (mm)
5( 39) Heartmate II Inflow Cannula Migration Does Not Predict Late-Term Complications K.A. Sell ,1 B. Sheridan,1 A.C. Kiser,1 A. Bowen,1 J.N. Katz,2 W.E. Stansfield.1 1Surgery, University of North Carolina, Chapel Hill, NC; 2Medicine, University of North Carolina, Chapel Hill, NC. Purpose: Heartmate II inflow cannula migration is hypothesized to contribute to late term complications. We used chest radiography (CXR) to study inflow cannula (IC) migration. We sought to understand patient variables that might
Abstracts S201 contribute to cannula migration. We tested the association between cannula migration and late term complications. Methods: We collected data and CXR on 80 consecutive heart mate II patients. We measured IC angle relative to the sternum on early post-op CXR - posteroanterior (PA), lateral (Lat), and anteroposterior (AP) views. To identify cannula migration, we compared initial cannula angles to cannula angles measured at 2-6 months, 6-12 months, and greater than 12 months using paired t-tests. We used linear regression analysis to test the relationship between cannula migration and patient factors including weight gain, age, ischemic or non-ischemic etiology, and Left Ventricle (LV) chamber size at time of implant. We utilized logistic regression to test the relationship between late-term outcomes and cannula migration. Results: AP CXR shows the inflow cannula moves 8.1 (95% CI 4.1-12 .1) degrees toward the abdomen between initial CXR and follow-up AP CXR after 2 months. After 12 months, PA CXR shows the IC pointing an additional 5.9 (95% CI 3.5-8.2) degrees toward the abdomen, and the lateral CXR shows the IC pointing 10.3 (95% CI 7.6-12.9) degrees more towards the abdomen. Essentially, the body of the pump is pushed up and the cannula tip angles further down. The average weight gain is 6.5 (SD 18) kg. Weight gain is more common in younger patients and those with smaller ventricles (p< 0.05). On lateral CXR, more weight gain and larger LV dimension are associated with greater IC position changes (p< 0.05). On PA view, only female gender is associated with increased cannula migration (p< 0.05). Multivariate logistic regression does not demonstrate a relationship between cannula movement and late-term complications including death, stroke, and right heart failure. Even among the 10 most extremely shifted cannulas on PA or lateral view, a composite of these outcomes was only identified twice. Conclusion: Inflow cannula migration is readily followed with PA and Lateral CXR. It is influenced by weight gain, larger initial LV dimension, and gender. However, even large changes in cannula angulation that occur in outpatients do not predict death, stroke, or right heart failure. 5( 40) Outcomes of Minimally Invasive Approach for Exchange of the HeartMate II (HMII) Left Ventricular Assist Device (LVAD) B. Soleimani , L.C. Price, E.R. Stephenson, A. El-Banayosy, W.E. Pae. Cardiothoracic Surgery, Penn State Hershey Medical Center, Hershey, PA. Purpose: The safety and efficacy of HMII pump exchange using the minimally invasive subcostal approach remains unclear. We hypothesized that avoiding re-do sternotomy for pump exchange would result in a reduction in operative mortality and morbidity. Methods: We conducted a retrospective review of all continuous flow LVADs implanted since June 2006 at our institution. Patients who underwent a HMII pump exchange were identified and divided into a subcostal (SC) and median sternotomy (MS) group. Data pertaining to their short and long term outcomes were collected. Results: Of the 123 patients who had a continuous flow LVAD implanted, 21 (17%) had pump failure needing pump exchange. 17 patients had a HMII pump exchange, of which 9 were performed through MS and 8 through SC approach. Mean LVAD support duration before exchange was 540±450 days and was not significantly different between MS and SC groups. There were no 30-day peri-operative deaths with either approach. Compared with sternotomy, patients with subcostal approach had significantly shorter operative times, lower re-operation rates for bleeding and required fewer transfused blood products. Additionally, patients with subcostal approach had shorter postoperative intensive care unit stays and total hospital stays.
Long-term survival after mean follow up of 260 days for the subcostal group and 232 days for the sternotomy group was 75% and 33% respectively. Conclusion: Exchange of the HMII pump can be accomplished with a low morbidity and mortality and good long-term outcomes, through a less invasive subcostal approach.
5( 41) HeartMate II Pump Exchange in the Continuous Flow Pump Era Is Associated with Increased Mortality L. Harvey , R. Cogswell, C. Holley, R. John, P. Eckman, K. Liao. University of Minnesota, Minneapolis, MN. Purpose: Although left ventricular assist devices (LVADs) significantly improve survival in patients with end stage heart failure, pump exchanges are occasionally required for device malfunction or pump thrombosis. We sought to evaluate the effect of undergoing a pump exchange on long-term mortality using data from a large single center LVAD cohort. Methods: The cohort consisted of 239 patients implanted with HeartMate II (HM II) LVADs between June 2005 and June 2013 at a single center. To assess the impact of HM II device exchanges on long-term mortality, a multivariable cox regression analysis was performed. Given cardiac transplant represents a competing risk in this analysis, the Fine Gray method was used. Results: 239 patients (187 bridge to transplant, 52 destination therapy) underwent HM II implantation. During the subsequent HM II LVAD follow-up time of 364 person-years, 14 HM II pump exchanges occurred among 13 patients for an event rate of 0.04 exchanges/patient year of support. The mean time to exchange was 422 days +/- 364 days. The indications for HM II exchange were pump thrombosis (10/14, 71%) and driveline failure (4/14, 29%). Prior pump exchange was associated with a 7.1 fold increase in the odds of subsequent pump exchange (OR 7.1, 95% CI 1.6 - 31, p < 0.01). Bridge to transplant status was associated with an 82% reduction in the odds of device exchange (OR 0.18, 95 % CI 0.07 - 0.44, p < 0.0001). During the entire length of LVAD follow up, patients with any device exchange had 1.9 times the rate (hazard) of death (HR 1.9, 95% CI 1.1 - 3.5, p < 0.05). In the adjusted model (for age, chronic kidney disease and history of driveline infection), patients with any device exchange had 2.2 times the rate (hazard) of death (HR 2.2, 95% CI 1.2 - 4.0, p < 0.05) compared to patients who did not require pump exchanges. Conclusion: While the rate of pump exchange was relatively low in this single center study, pump exchange was associated with a higher mortality while on mechanical support. Larger scale data will be needed to confirm this finding and to understand the mechanism of this increased risk. Reducing the risk of pump thrombosis possibly with improved anticoagulation strategies will favorably influence clinical outcomes in these patients.
The Journal of Heart and Lung Transplantation, Vol 32, No 4S, April 2014
56% and 95%, 92%, 86% respectively. Pre- and peri-operative variables influencing the development of post-implant RD in this normal cohort were: history of atrial arrhythmia (OR 4.37 CI 1.10-17.32 p= 0.026), raised mean Right Atrial Pressure (mRAP / mmHg) (19.50 + 6.49 vs 14.66 + 5.88 p= 0.021), cardiopulmonary bypass time (CPB / min) 142.85+ 64.69 vs 110.59 + 34.96 p= 0.011), total length of surgery (hr) (6.91 + 3.12 vs 5.7 + 1.32 p= 0.026), intraoperative FFP (units) (6.09 +13.06 vs 2.70 + 2.04 p= 0.046) and Cryoprecipitate (units) ( 4.0 + 5.91 vs 1.77 + 2.36 p= 0.026) transfusion. Postoperative variables correlating with RD were Cryoprecipitate (2.83 + 5.42 vs 0.52 + 2.13 p= 0.011) and platelet (1.33 + 22.23 vs 0.4 + 0.85 p= 0.012) transfusions, days on post-op inotropes (45.23 + 113.33 vs 10.69 + 9.74 p= 0.022), length of ICU stay (days) (22.08 + 18.21 vs 12.88 + 10.67 p= 0.015) and re-exploration for bleeding (OR 4.73 CI 0.92 - 24.33 p= 0.046). Conclusion: Post VAD-implant RD in patients with normal pre-operative renal function confers significant morbidity and survival disadvantage. This study reinforces the need to better optimize pre-operative volume status, limit bypass and surgical times, reduce peri- and post operative blood product transfusions, and avoid re-exploration for bleeding. 5( 37) The Impact of Baseline Renal Dysfunction on Patient Outcomes after Implantation of Chronic Mechanical Circulatory Support Devices C. Anthony ,1 R. Lui,2 J. Sevastos,3 K. Dhital,1 E. Granger,1 C.S. Hayward,1 A. Jabbour,1 P.C. Jansz,1 A.M. Keogh,1 E. Kotlyar,1 D. Robson,1 P.S. Macdonald,1 P.M. Spratt.1 1Heart & Lung Transplant Unit, “St. Vincent’s Health Network, Sydney, Australia; 2St Vincent’s Hospital Clinical School, University of New South Wales, Sydney, Australia; 3Department of Renal Medicine, St. Vincent’s Health Network, Sydney, Australia. Purpose: To assess the impact of baseline renal dysfunction on morbidity and mortality after chronic mechanical circulatory support (MCS) implantation. Methods: Retrospective review of 101 consecutive MCS patients implanted between November 2006 and October 2013 (89 LVAD, 7 BiVAD and 5 TAH; M:F 77:24; mean age 49 +/- 15 years; Intermacs class I:II-III 27:74). eGFR (MDRD formula) on the day of implant was > 90 in 13, 60-89 in 38, 30-59 in 47 and < 30 ml/min/1.73m2 in 3 patients. Acute kidney injury (AKI) grade by RIFLE criteria (1) in the month prior to MCS implant was no injury (N) in 54, risk (R) in 20, injury (I) in 17 and failure (F) in 10 patients. Outcomes of the 3 patients with baseline eGFR < 30 ml/min/1.73m2 and the 10 patients with RIFLE F AKI (RF group) were compared with the remaining 88 patients (non-RF group). Results: Compared with the non-RF group, the RF group had increased requirement for post-MCS renal replacement therapy (62% vs 13%, p< 0.002) and length of stay (54 +/- 9 vs 38 +/- 2 days, p < 0.02). Actuarial survival at 6 and 12 months (Figure 1) was 59 +/- 14 and 49 +/- 15 % in the RF group versus 92 +/- 3 and 78 +/- 5% in the non-RF group (p < 0.01). Conclusion: Patients with baseline eGFR < 30 ml/min/1.73m2 or severe AKI (RIFLE F) in the month pre-MCS implant are at high risk of acute renal failure post-MCS implant. Morbidity is high and survival is poor in this group. In contrast, patients with lesser degrees of renal impairment have excellent post-MCS outcomes. Reference (1) Bellomo R, Ronco C, Kellum JA, et al. Crit Care, 2004, Vol. 8. R204-12.
5( 38) Assessment of the LVAD Inflow Cannula Position by Cardiac CT K. Ghafourian ,1 W.G. Weigold,1 S.M. Jani,1 D. Abramov,1 G. Ruiz,1 M. Hofmeyer,1 D.T. Majure,1 F.H. Sheikh,1 R.D. Bannerman,1 E.J. Molina,2 S.W. Boyce,2 S.S. Najjar,1 G. Weissman.1 1Cardiology, Medstar Washington Hospital Center, Washington, DC; 2Surgery, Medstar Washington Hospital Center, Washington, DC. Purpose: Position of the inflow cannula (IC) within the left ventricle may affect optimal function of the LVAD and contribute to the risk of complications. We evaluated the intraventricular position of the IC in Heartmate II (HM2) and Heartware (HW) LVADs. Methods: A single-center retrospective review of the most recent cardiac CT (CCT) of all continuous flow LVAD implants between 10/2006 and 9/2013 was performed. CT acquisitions were completed on a 64 or 256 slice platform using ECG gated helical technique. Measurements were performed in standard 2-chamber and short-axis views. Fisher’s exact and Wilcoxon-MannWhitney tests were used to determine statistical difference between groups. Results: A total of 195 patients underwent LVAD implants (101 HM2, 94 HW). At least one CCT was performed on 63 patients. Mean LV end diastolic diameter was 63 ± 11 mm. Apical tip of the IC was more frequently in contact with anterior wall in the HM2 patients (15/24, 62%) compared to HW pumps (5/38, 13%, p< 0.001). Basal tip did not abut the anterior wall in any patient. Septal wall contact was 25% vs. 5 % (p= 0.05) and lateral wall contact was 29% vs. 25% (p= 0.7) in HM2 and HW pumps, respectively. In the total population, the IC was angulated towards the mitral annulus plane (median 33 degrees, IQR 22, 46) and formed a 77-degree horizontal angle in the short axis (IQR 57, 95, figure 1). Angle of the IC was significantly different between HM2 and HW LVADs (table 1). Conclusion: Significant variation exists among patients and between two different types of continuous-flow LVAD with regards to intraventricular position of the inflow cannula. Clinical significance of these variations remains to be determined. Table 1.
Inflow cannula position within the ventricle in HM2 and HW LVADs.
Inflow Cannula Distance/Position (median, IQR)
Total (N= 63)
HM2 (N= 24)
HW (N= 39 )
P-value
16 (8,24)
12 (3,18)
18 (12,27)
0.008
IC tip to lateral wall 10 (0,16) (mm)
8 (0,10)
15 (3,18)
0.020
IC apical tip to anterior wall (mm)
14 (0,25)
0 (0,16)
18 (10,30)
< 0.001
IC basal tip to anterior wall (mm)
29 (20,39)
30 (17,40)
29 (23,38)
0.6
Angulation towards 33 (22,46) base (degree)
43 (35,47)
26 (10,44)
0.001
Angulation towards 77 (57,95) lateral wall (degree)
89 (80,120)
62 (52,86)
< 0.001
IC tip to septum (mm)
5( 39) Heartmate II Inflow Cannula Migration Does Not Predict Late-Term Complications K.A. Sell ,1 B. Sheridan,1 A.C. Kiser,1 A. Bowen,1 J.N. Katz,2 W.E. Stansfield.1 1Surgery, University of North Carolina, Chapel Hill, NC; 2Medicine, University of North Carolina, Chapel Hill, NC. Purpose: Heartmate II inflow cannula migration is hypothesized to contribute to late term complications. We used chest radiography (CXR) to study inflow cannula (IC) migration. We sought to understand patient variables that might
Abstracts S201 contribute to cannula migration. We tested the association between cannula migration and late term complications. Methods: We collected data and CXR on 80 consecutive heart mate II patients. We measured IC angle relative to the sternum on early post-op CXR - posteroanterior (PA), lateral (Lat), and anteroposterior (AP) views. To identify cannula migration, we compared initial cannula angles to cannula angles measured at 2-6 months, 6-12 months, and greater than 12 months using paired t-tests. We used linear regression analysis to test the relationship between cannula migration and patient factors including weight gain, age, ischemic or non-ischemic etiology, and Left Ventricle (LV) chamber size at time of implant. We utilized logistic regression to test the relationship between late-term outcomes and cannula migration. Results: AP CXR shows the inflow cannula moves 8.1 (95% CI 4.1-12 .1) degrees toward the abdomen between initial CXR and follow-up AP CXR after 2 months. After 12 months, PA CXR shows the IC pointing an additional 5.9 (95% CI 3.5-8.2) degrees toward the abdomen, and the lateral CXR shows the IC pointing 10.3 (95% CI 7.6-12.9) degrees more towards the abdomen. Essentially, the body of the pump is pushed up and the cannula tip angles further down. The average weight gain is 6.5 (SD 18) kg. Weight gain is more common in younger patients and those with smaller ventricles (p< 0.05). On lateral CXR, more weight gain and larger LV dimension are associated with greater IC position changes (p< 0.05). On PA view, only female gender is associated with increased cannula migration (p< 0.05). Multivariate logistic regression does not demonstrate a relationship between cannula movement and late-term complications including death, stroke, and right heart failure. Even among the 10 most extremely shifted cannulas on PA or lateral view, a composite of these outcomes was only identified twice. Conclusion: Inflow cannula migration is readily followed with PA and Lateral CXR. It is influenced by weight gain, larger initial LV dimension, and gender. However, even large changes in cannula angulation that occur in outpatients do not predict death, stroke, or right heart failure. 5( 40) Outcomes of Minimally Invasive Approach for Exchange of the HeartMate II (HMII) Left Ventricular Assist Device (LVAD) B. Soleimani , L.C. Price, E.R. Stephenson, A. El-Banayosy, W.E. Pae. Cardiothoracic Surgery, Penn State Hershey Medical Center, Hershey, PA. Purpose: The safety and efficacy of HMII pump exchange using the minimally invasive subcostal approach remains unclear. We hypothesized that avoiding re-do sternotomy for pump exchange would result in a reduction in operative mortality and morbidity. Methods: We conducted a retrospective review of all continuous flow LVADs implanted since June 2006 at our institution. Patients who underwent a HMII pump exchange were identified and divided into a subcostal (SC) and median sternotomy (MS) group. Data pertaining to their short and long term outcomes were collected. Results: Of the 123 patients who had a continuous flow LVAD implanted, 21 (17%) had pump failure needing pump exchange. 17 patients had a HMII pump exchange, of which 9 were performed through MS and 8 through SC approach. Mean LVAD support duration before exchange was 540±450 days and was not significantly different between MS and SC groups. There were no 30-day peri-operative deaths with either approach. Compared with sternotomy, patients with subcostal approach had significantly shorter operative times, lower re-operation rates for bleeding and required fewer transfused blood products. Additionally, patients with subcostal approach had shorter postoperative intensive care unit stays and total hospital stays.
Long-term survival after mean follow up of 260 days for the subcostal group and 232 days for the sternotomy group was 75% and 33% respectively. Conclusion: Exchange of the HMII pump can be accomplished with a low morbidity and mortality and good long-term outcomes, through a less invasive subcostal approach.
5( 41) HeartMate II Pump Exchange in the Continuous Flow Pump Era Is Associated with Increased Mortality L. Harvey , R. Cogswell, C. Holley, R. John, P. Eckman, K. Liao. University of Minnesota, Minneapolis, MN. Purpose: Although left ventricular assist devices (LVADs) significantly improve survival in patients with end stage heart failure, pump exchanges are occasionally required for device malfunction or pump thrombosis. We sought to evaluate the effect of undergoing a pump exchange on long-term mortality using data from a large single center LVAD cohort. Methods: The cohort consisted of 239 patients implanted with HeartMate II (HM II) LVADs between June 2005 and June 2013 at a single center. To assess the impact of HM II device exchanges on long-term mortality, a multivariable cox regression analysis was performed. Given cardiac transplant represents a competing risk in this analysis, the Fine Gray method was used. Results: 239 patients (187 bridge to transplant, 52 destination therapy) underwent HM II implantation. During the subsequent HM II LVAD follow-up time of 364 person-years, 14 HM II pump exchanges occurred among 13 patients for an event rate of 0.04 exchanges/patient year of support. The mean time to exchange was 422 days +/- 364 days. The indications for HM II exchange were pump thrombosis (10/14, 71%) and driveline failure (4/14, 29%). Prior pump exchange was associated with a 7.1 fold increase in the odds of subsequent pump exchange (OR 7.1, 95% CI 1.6 - 31, p < 0.01). Bridge to transplant status was associated with an 82% reduction in the odds of device exchange (OR 0.18, 95 % CI 0.07 - 0.44, p < 0.0001). During the entire length of LVAD follow up, patients with any device exchange had 1.9 times the rate (hazard) of death (HR 1.9, 95% CI 1.1 - 3.5, p < 0.05). In the adjusted model (for age, chronic kidney disease and history of driveline infection), patients with any device exchange had 2.2 times the rate (hazard) of death (HR 2.2, 95% CI 1.2 - 4.0, p < 0.05) compared to patients who did not require pump exchanges. Conclusion: While the rate of pump exchange was relatively low in this single center study, pump exchange was associated with a higher mortality while on mechanical support. Larger scale data will be needed to confirm this finding and to understand the mechanism of this increased risk. Reducing the risk of pump thrombosis possibly with improved anticoagulation strategies will favorably influence clinical outcomes in these patients.