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Evaluation of Pump Speed Changes with Exercise in Patients with Continuous Flow Ventricular Assist Devices
Abstracts S155 4( 07) Left Ventricular (LV) Response to Unloading by Continuous-flow Left Ventricular Assist Devices (LVAD): Axial Vs. Centrifugal? A. Rauf , A.K. Johnson, G.A. Wright, S. Stoker, B.B. Reid, W.T. Caine, M.K. Goddard, R. Alharethi, G.E. Thomsen, D. Budge, S.E. Clayson, B.Y. Rasmusson, A.G. Kfoury. Mechanical Circulatory Support, Intermountain Medical Center, Salt Lake City, UT. Purpose: The use of LVAD as a therapy for end-stage heart failure is steadily increasing. Studies have shown different responses of the LV to volume and pressure unloading between pulsatile and continuous flow LVADs. This study investigates whether different continuous LVADs result in the same degree of changes in LV function and size. Methods: The Artificial Heart Program at Intermountain Medical Center (IMC) was queried for continuous flow LVAD patients implanted between December 2004 and July 2013. 2D Transthoracic echocardiograms for each patient were evaluated at pre-implant and 3 subsequent times (3 mos., 6 mos., 12 mos.). Data included LV ejection fraction (LVEF) and diastolic left ventricular internal dimension (LVIDd). Significance was determined by 2-Tailed Student’s T-Test. Results: 46 axial flow (AF) and 18 centrifugal flow (CF) LVAD patients were included in this study at implant, with mean support times of 519 and 361 days, respectively. Echo exams were carried out per IMC’s standard clinical protocol, at baseline pump settings determined to provide optimal support to each patient. Results of 2D Echo indicated that LVEF improved from 18% to 24% within 6 months for AF patients (p < 0.05). No significant changes occurred in CF (p > 0.05). The LVIDd changed from 6.32 cm to 5.06 cm within 6 months for AF (p < 0.05) and from 6.97 cm to 5.78 cm within 1 year for CF (p < 0.05) (See figure). Conclusion: These results suggest different responses in LV function and a delay in LV dimension change in AF and CF LVADs. Whether this is the result of differences in the type and extent of LVAD-induced unloading remains to be determined. Further research is needed given the possible implications on patient management and outcomes and future device design.
4( 08) From Bench To Bedside: Can the Improvements in LVAD Design Mitigate Adverse Events and Increase Survival Rate? V. Tarzia ,1 G. Di Giammarco,2 M. Maccherini,3 T. Bottio,1 V. Tursi,4 M. Maiani,4 S. Bernazzali,3 M. Foschi,2 S.M. Diso,2 U. Livi,4 G. Sani,5 G. Gerosa.1 1Department of Cardiac, Thoracic and Vascular Sciences, Cardiac Surgery, University of Padova, Padova, Italy; 2Cardiac Surgery, University of Chieti, Chieti, Italy; 3Cardiac Surgery, University of Siena, Siena, Italy; 4Cardiac Surgery, University of Udine, Udine, Italy; 5Cardiac Surgery, University of Florence, Florence, Italy. Purpose: In vitro tests showed that the recent cone bearing configuration of Jarvik 2000 LVAD exhibits greater flow rates and hydraulic efficiency than the previous pin bearing design. We investigated long-term outcomes of patients implanted with Jarvik 2000 LVAD and enrolled in the Italian Registry (IR), depending on device mechanical configuration. Methods: From May 2008 to September 2013, 104 consecutive end-stage heart failure patients were enrolled in the Jarvik 2000 IR. Of these 90 were males and 99 were adult (mean age 61±9 yrs, median 63 yrs, 51% ischemic
cardiomyopathy, 82% ineligible for heart transplantation, 95% with post auricular drive-line). Up to June 2010 40 pts were implanted with a pin bearing pump (Group A) whereas from July 2010 to September 2013 59 adult patients received a cone bearing pump (Group B). Relevant pre-operative data, long term outcomes and major adverse events were analyzed by comparing retrospectively the two groups. Results: 31/40 pts (Group A1) and 45/59 pts (Group B1) were discharged at home. No significant difference in etiology, pre-operative hemodynamics and pre-implant INTERMACS mean class (3.5 and 3.0 respectively) were found between the two groups. Kaplan-Meier survival at 1 and 2 years increased in B1 vs A1 (83% vs 64% and 68% vs 47% respectively). No pump failure occurred in both groups. In B1 vs A1 we observed a decrease in events per patient year of antithrombotic therapy related ischemic and hemorrhagic stroke (49 and 80% respectively), right ventricular failure (40%) and gastrointestinal bleeding (28%). Driveline and device infection remained negligible in both groups. Conclusion: In our experience, patients with the new pump configuration showed a better survival and a reduced thromboembolic and hemorrhagic risk. Further studies are needed to prove the favorable impact of pump enhanced fluidynamics in reducing complications and improving long-term results. 4( 09) Left Ventricular Remodeling Following LVAD: Does Pulsatility Matter? M.K. Bennett , W.E. Sweet, S. Baicker-McKee, R.C. Starling, N. Moazami, C.S. Moravec. Department of Cardiovascular Medicine, Cleveland Clinic, Cleveland, OH. Purpose: Left ventricular assist device (LVAD) support of the failing human heart has been associated with functional and molecular remodeling. Continuous flow (CF) LVADs are now used more widely than pulsatile flow (PF) LVADs. CF and PF LVADs unload the failing heart to different degrees, and we hypothesized that the two types of LVAD might result in different degrees of remodeling. We tested this hypothesis using two well-accepted cellular alterations in heart failure, calcium cycling proteins and beta adrenergic receptors/response. Methods: Western blot analysis was used to compare levels of calcium cycling proteins in non-failing, failing, and LVAD-supported failing human hearts. The LVAD group was separated into two subgroups: those supported with the PF Heartmate (HM) device and those supported with the CF Heartmate II (HMII) device. LVAD-supported patients in both groups were chosen so that they were matched for age, etiology, and support duration. Total beta adrenergic receptor density was measured by radioligand binding. We examined the inotropic response to beta adrenergic stimulation in left ventricular trabecular muscles using the non-selective beta agonist, isoproterenol. All experiments were performed on the same groups of hearts. Results: Data show that the calcium binding proteins SERCA and S100A1 are down-regulated in failing hearts, as we have previously shown. Hearts supported with HM, but not HMII, show recovery of SERCA protein to levels measured in non-failing controls. S100A1 protein does not recover in hearts supported by either HM or HMII. The other calcium cycling proteins which were investigated in this study do not change in failure or after CF or PF. Beta adrenergic receptor density is restored to non-failing levels after either HM or HMII support. The inotropic response to beta adrenergic stimulation, impaired in failing hearts, is recovered to non-failing levels after both HM and HMII. Conclusion: These data suggest that CF and PF LVADs have differential effects on at least some of the cellular and molecular changes associated with human heart failure, including SERCA and S100A1, while other changes, such as beta adrenergic receptor density and response, recover with either type of LVAD. Differences in the recovery of SERCA and S100A1 may have significant implications as we consider the ability of LVADs to reverse the heart failure phenotype and promote myocardial recovery. 4( 10) Evaluation of Pump Speed Changes with Exercise in Patients with Continuous Flow Ventricular Assist Devices J.V. Lai , K. Muthiah, R. Prichard, R. Walker, D. Robson, C. Lim, L.W. Wang, P.S. Macdonald, P. Jansz, C.S. Hayward. Heart and Lung Transplant Unit, St Vincent’s Hospital, Sydney, Australia.
S156
The Journal of Heart and Lung Transplantation, Vol 32, No 4S, April 2014
Purpose: The spontaneous increase in pump flow accompanying exercise in cfLVAD patients is slight in comparison to the physiological response, limiting exercise capacity. Given the strong linear relationship between pump speed and flow, augmentation of pump flow with activity through pump speed modulation is an intuitive line of investigation.We investigated whether operating a cfLVAD at a higher pump speed improves central haemodynamics with graded exercise as compared to operation at baseline speed. Methods: Nine patients (median age 60, range 41-70) implanted with the HeartWare HVAD underwent right heart catheterisation and were monitored using a computerised data acquisition system, continuous cardiac output monitor and echocardiography. At rest, pump speed was gradually increased to determine a safe working maximum. Patients then performed incremental exercise until exhaustion at both baseline and maximum pump speeds. Results: Pump speed was safely increased to 320rpm above baseline in all patients. Median maximum speed was 2920 rpm. Significantly greater pump flows were achieved with maximum pump speed compared to baseline speed during light exercise (6.8 ± 0.8 L/min vs. 5.8 ± 0.8 L/min, p = 0.007) and peak exercise (7.7 ± 0.6 L/min vs. 6.9 ± 0.7 L/min, p = 0.008). PCWP was significantly reduced at peak exercise by maximum speed compared to baseline speed (28 ± 8 mmHg vs. 31 ± 9 mmHg, p = 0.01). Heart rate was also significantly lower at peak exercise with maximum speed (112 ± 25 vs. 122 ± 33, p = 0.01). Right atrial pressure, mean pulmonary arterial pressure and mixed venous oxygen saturation were unaffected by changes in pump speed. Conclusion: This study provides support for the adjustment of pump speed with activity. Increasing pump speed augments flow while blunting the increase in wedge pressure that accompanies exercise. 4( 11) TNF as a Predictor of Myocardial Functional Improvement Induced By Left Ventricular Mechanical Unloading N. Diakos ,1 C. Yen,1 O. Wever-Pinzon,1 C. Selzman,1 B. Reid,2 J. Stehlik,1 A. Kfoury,2 R. Alharethi,2 J. Nativi,1 A. Catino,1 C. Davis,1 J. Barney,1 S. Wright,1 A. Koliopoulou,1 J. Fang,1 D. Li,1 S. Drakos.1 1University of Utah, Salt Lake City, UT; 2Intermountain Medical Center, Salt Lake City, UT. Purpose: Inflammation plays a central role in the pathogenesis of heart failure and the levels of the pro-inflammatory cytokine, Tissue Necrosis Factor (TNF), have been correlated with the severity of disease. We hypothesized that TNF levels would also correlate with the ability of the failing human heart to improve its endogenous function after mechanical unloading induced by left ventricular assist devices (LVAD). Methods: We examined 83 patients supported with LVAD as a bridge to transplantation. Left ventricular function was evaluated both before and serially after LVAD implantation, using echocardiography with LVAD turndown. LVAD- induced myocardial functional “Response” was defined as a relative increase in left ventricular (LV) ejection fraction > 50% and a relative decrease in LV end- systolic volumes > 20% (“Responders”). Left Ventricular (LV) biopsies and peripheral blood were collected at the time of LVAD implantation. Myocardial mRNA levels of TNF were quantified by RT-qPCR. Also, protein levels of TNF were measured both in myocardial tissue and in serum using ELISA. Results: Myocardial function improved significantly in 16 patients (19%i.e. “Responders”). Both myocardial tissue TNF mRNA expression and TNF protein levels were significantly lower in Responders at the pre- LVAD implantation time point -0.07±0.01 vs 0.21±0.05 AU, p= 0.02 and 0.4±0.06 vs 0.7±0.07 pg/ml, p= 0.0012, respectively. Serum TNF protein levels, measured before the initiation of LVAD unloading, were also significantly lower in Responders - 7.8±1.1 vs 12.8±1 pg/ml, p< 0.001. Further, serum TNF levels at the pre-LVAD implantation time point were inversely correlated to the degree of change of LV ejection fraction induced by LVAD unloading (r= -0.4, p= 0.0016). Conclusion: TNF levels in myocardial tissue and serum obtained at the time of LVAD implant inversely correlate with the ability of the heart to significantly improve its endogenous function during LVAD- induced mechanical unloading. The utility of TNF as a potential biomarker to predict unloadinginduced myocardial recovery warrants further investigation.
4( 12) Percutaneous Balloon Occlusion of a Left Ventricular Assist Device Outflow Cannula During Right Heart Catheterization With Pumpstop as Part of the Evaluation of Myocardial Recovery J. Vierecke , M. Hernánedes-Enriquez, M. Dandel, M. Müller, P. Stawowy, S. Dreysse, E. Potapov, T. Krabatsch, R. Hetzer. Deutsches Herzzentrum Berlin, Berlin, Germany. Purpose: Off-pump trials to evaluate myocardial recovery in pts.supported by continuous-flow pumps might be more challenging than with pulsatile-flow devices because of retrograde flow through the left ventricular assist device (LVAD). In 2011 we described the first case of right heart catheterization with balloon occlusion during an off-pump trial. The present study aims to analyze the measurements and follow-up of right heart catheterization during percutaneous occlusion of VAD outflow cannula as part of the evaluation of weaning potential. Methods: Between 5/2006 and 11/2013 we implanted 210 HeartMate II and 412 HeartWare pumps at our center. Between 05/2011 and 08/2013 a total of 20 patients on VAD who showed weaning potential by echocardiography were evaluated by right heart catheterization during pump stop and balloon occlusion. Measurements were taken with optimal rotation of the LVAD and pump stop with the outflow graft occluded by inflating the balloon catheter. To occlude the outflow graft, different balloon catheters were used. We considered LVAD explantation to be safely possible if cardiac output, PA and PCWP remain stable in the off-pump trial with balloon occlusion. Results: A total of 20 patients received 22 off-pump trials. 80% were male. Median age was 49.5 years (min/max 24/64y). 14 patients were supported by HeartWare and 6 by Heartmate II LVAD. 6 patients were anticoagulated with refludan due to HIT II, all others were anticoagulated with heparin There were 5 pts. with increase of PCWP and PAP over 30% during ballon occlusion, 1 with only increase in PCW and 1 other with increase only in PAP. A decrease in cardiac output was seen in 5 pts., all others showed stable pressures. There were no complications or deaths related to the catheterization. 11 pts. (55%) were considered to have weaning potential. 8 were explanted and 2 others were scheduled. One is still on assist due to increased LVEDD and rhythm disturbances. Two patients died due to sepsis/infection during follow up. All explanted patients were free from heart failure recurrence (mean follow up time 20 month). Conclusion: Evaluation of weaning potential from VADs by heart catheterization during pump stop and balloon occlusion of the outflow cannula is a safe procedure and a valuable tool for guiding decisions on VAD explantation. 4( 13) Influence of MELD (Model of End-Stage Liver Disease)_XI (eXcluding INR) on Post-Heart Transplant (HT) Outcomes E.C. DePasquale , A. Nsair, L. Reardon, A. Ardehali, M. Deng. UCLA, Los Angeles, CA. Purpose: Liver dysfunction increases post-surgical morbidity and mortality. MELD-XI has been evaluated in ambulatory heart failure patients and in those receiving VAD support in a single center. We sought to evaluate MELD-XI in a national cohort. Methods: 40465 HT recipients were identified from UNOS (1987-2011) and stratified by MELD-XI score > = 17 (n= 24013) or < 17 (n= 16442) calculated using creatinine and bilirubin at time of transplant. Exclusions: age< 18, re-HT & lost to follow up, missing creatinine and bilirubin. Survival was censored at 12y. Multivariate Cox proportional hazard regression analysis was adjusted for age, sex, DM, race, ischemic time, dialysis, life support, VAD use, wait time & HLA mismatch. Results: ELD-XI > = 17 was associated with younger age (p< 0.001), less prior cardiac surgery (p< 0.001), younger donor age (p< 0.001), less VAD use (p< 0.001) and increased ventilator use (p< 0.001) with a shorter wait time (p< 0.001). MELD-XI > = 17 were more likely to be listed as status 2 (30% vs 24%, p< 0.001). Survival (1, 5 & 10y) was: MELD-XI < 17 (89, 74, 54%) & MELD-XI > = 17(81, 65, 45%) (Figure). Unadjusted HR (compared to MELD-XI < 17) for all-cause mortality was 1.35 (CI 1.31-1.40). Multivariate analysis yielded a HR of 1.40 (CI 1.35-1.45). Conclusion: Survival is significantly reduced post-HT in patients with MELD-XI > = 17. Prospective study is warranted as MELD-XI may provide insight into patient selection.
4( 08) From Bench To Bedside: Can the Improvements in LVAD Design Mitigate Adverse Events and Increase Survival Rate? V. Tarzia ,1 G. Di Giammarco,2 M. Maccherini,3 T. Bottio,1 V. Tursi,4 M. Maiani,4 S. Bernazzali,3 M. Foschi,2 S.M. Diso,2 U. Livi,4 G. Sani,5 G. Gerosa.1 1Department of Cardiac, Thoracic and Vascular Sciences, Cardiac Surgery, University of Padova, Padova, Italy; 2Cardiac Surgery, University of Chieti, Chieti, Italy; 3Cardiac Surgery, University of Siena, Siena, Italy; 4Cardiac Surgery, University of Udine, Udine, Italy; 5Cardiac Surgery, University of Florence, Florence, Italy. Purpose: In vitro tests showed that the recent cone bearing configuration of Jarvik 2000 LVAD exhibits greater flow rates and hydraulic efficiency than the previous pin bearing design. We investigated long-term outcomes of patients implanted with Jarvik 2000 LVAD and enrolled in the Italian Registry (IR), depending on device mechanical configuration. Methods: From May 2008 to September 2013, 104 consecutive end-stage heart failure patients were enrolled in the Jarvik 2000 IR. Of these 90 were males and 99 were adult (mean age 61±9 yrs, median 63 yrs, 51% ischemic
cardiomyopathy, 82% ineligible for heart transplantation, 95% with post auricular drive-line). Up to June 2010 40 pts were implanted with a pin bearing pump (Group A) whereas from July 2010 to September 2013 59 adult patients received a cone bearing pump (Group B). Relevant pre-operative data, long term outcomes and major adverse events were analyzed by comparing retrospectively the two groups. Results: 31/40 pts (Group A1) and 45/59 pts (Group B1) were discharged at home. No significant difference in etiology, pre-operative hemodynamics and pre-implant INTERMACS mean class (3.5 and 3.0 respectively) were found between the two groups. Kaplan-Meier survival at 1 and 2 years increased in B1 vs A1 (83% vs 64% and 68% vs 47% respectively). No pump failure occurred in both groups. In B1 vs A1 we observed a decrease in events per patient year of antithrombotic therapy related ischemic and hemorrhagic stroke (49 and 80% respectively), right ventricular failure (40%) and gastrointestinal bleeding (28%). Driveline and device infection remained negligible in both groups. Conclusion: In our experience, patients with the new pump configuration showed a better survival and a reduced thromboembolic and hemorrhagic risk. Further studies are needed to prove the favorable impact of pump enhanced fluidynamics in reducing complications and improving long-term results. 4( 09) Left Ventricular Remodeling Following LVAD: Does Pulsatility Matter? M.K. Bennett , W.E. Sweet, S. Baicker-McKee, R.C. Starling, N. Moazami, C.S. Moravec. Department of Cardiovascular Medicine, Cleveland Clinic, Cleveland, OH. Purpose: Left ventricular assist device (LVAD) support of the failing human heart has been associated with functional and molecular remodeling. Continuous flow (CF) LVADs are now used more widely than pulsatile flow (PF) LVADs. CF and PF LVADs unload the failing heart to different degrees, and we hypothesized that the two types of LVAD might result in different degrees of remodeling. We tested this hypothesis using two well-accepted cellular alterations in heart failure, calcium cycling proteins and beta adrenergic receptors/response. Methods: Western blot analysis was used to compare levels of calcium cycling proteins in non-failing, failing, and LVAD-supported failing human hearts. The LVAD group was separated into two subgroups: those supported with the PF Heartmate (HM) device and those supported with the CF Heartmate II (HMII) device. LVAD-supported patients in both groups were chosen so that they were matched for age, etiology, and support duration. Total beta adrenergic receptor density was measured by radioligand binding. We examined the inotropic response to beta adrenergic stimulation in left ventricular trabecular muscles using the non-selective beta agonist, isoproterenol. All experiments were performed on the same groups of hearts. Results: Data show that the calcium binding proteins SERCA and S100A1 are down-regulated in failing hearts, as we have previously shown. Hearts supported with HM, but not HMII, show recovery of SERCA protein to levels measured in non-failing controls. S100A1 protein does not recover in hearts supported by either HM or HMII. The other calcium cycling proteins which were investigated in this study do not change in failure or after CF or PF. Beta adrenergic receptor density is restored to non-failing levels after either HM or HMII support. The inotropic response to beta adrenergic stimulation, impaired in failing hearts, is recovered to non-failing levels after both HM and HMII. Conclusion: These data suggest that CF and PF LVADs have differential effects on at least some of the cellular and molecular changes associated with human heart failure, including SERCA and S100A1, while other changes, such as beta adrenergic receptor density and response, recover with either type of LVAD. Differences in the recovery of SERCA and S100A1 may have significant implications as we consider the ability of LVADs to reverse the heart failure phenotype and promote myocardial recovery. 4( 10) Evaluation of Pump Speed Changes with Exercise in Patients with Continuous Flow Ventricular Assist Devices J.V. Lai , K. Muthiah, R. Prichard, R. Walker, D. Robson, C. Lim, L.W. Wang, P.S. Macdonald, P. Jansz, C.S. Hayward. Heart and Lung Transplant Unit, St Vincent’s Hospital, Sydney, Australia.
S156
The Journal of Heart and Lung Transplantation, Vol 32, No 4S, April 2014
Purpose: The spontaneous increase in pump flow accompanying exercise in cfLVAD patients is slight in comparison to the physiological response, limiting exercise capacity. Given the strong linear relationship between pump speed and flow, augmentation of pump flow with activity through pump speed modulation is an intuitive line of investigation.We investigated whether operating a cfLVAD at a higher pump speed improves central haemodynamics with graded exercise as compared to operation at baseline speed. Methods: Nine patients (median age 60, range 41-70) implanted with the HeartWare HVAD underwent right heart catheterisation and were monitored using a computerised data acquisition system, continuous cardiac output monitor and echocardiography. At rest, pump speed was gradually increased to determine a safe working maximum. Patients then performed incremental exercise until exhaustion at both baseline and maximum pump speeds. Results: Pump speed was safely increased to 320rpm above baseline in all patients. Median maximum speed was 2920 rpm. Significantly greater pump flows were achieved with maximum pump speed compared to baseline speed during light exercise (6.8 ± 0.8 L/min vs. 5.8 ± 0.8 L/min, p = 0.007) and peak exercise (7.7 ± 0.6 L/min vs. 6.9 ± 0.7 L/min, p = 0.008). PCWP was significantly reduced at peak exercise by maximum speed compared to baseline speed (28 ± 8 mmHg vs. 31 ± 9 mmHg, p = 0.01). Heart rate was also significantly lower at peak exercise with maximum speed (112 ± 25 vs. 122 ± 33, p = 0.01). Right atrial pressure, mean pulmonary arterial pressure and mixed venous oxygen saturation were unaffected by changes in pump speed. Conclusion: This study provides support for the adjustment of pump speed with activity. Increasing pump speed augments flow while blunting the increase in wedge pressure that accompanies exercise. 4( 11) TNF as a Predictor of Myocardial Functional Improvement Induced By Left Ventricular Mechanical Unloading N. Diakos ,1 C. Yen,1 O. Wever-Pinzon,1 C. Selzman,1 B. Reid,2 J. Stehlik,1 A. Kfoury,2 R. Alharethi,2 J. Nativi,1 A. Catino,1 C. Davis,1 J. Barney,1 S. Wright,1 A. Koliopoulou,1 J. Fang,1 D. Li,1 S. Drakos.1 1University of Utah, Salt Lake City, UT; 2Intermountain Medical Center, Salt Lake City, UT. Purpose: Inflammation plays a central role in the pathogenesis of heart failure and the levels of the pro-inflammatory cytokine, Tissue Necrosis Factor (TNF), have been correlated with the severity of disease. We hypothesized that TNF levels would also correlate with the ability of the failing human heart to improve its endogenous function after mechanical unloading induced by left ventricular assist devices (LVAD). Methods: We examined 83 patients supported with LVAD as a bridge to transplantation. Left ventricular function was evaluated both before and serially after LVAD implantation, using echocardiography with LVAD turndown. LVAD- induced myocardial functional “Response” was defined as a relative increase in left ventricular (LV) ejection fraction > 50% and a relative decrease in LV end- systolic volumes > 20% (“Responders”). Left Ventricular (LV) biopsies and peripheral blood were collected at the time of LVAD implantation. Myocardial mRNA levels of TNF were quantified by RT-qPCR. Also, protein levels of TNF were measured both in myocardial tissue and in serum using ELISA. Results: Myocardial function improved significantly in 16 patients (19%i.e. “Responders”). Both myocardial tissue TNF mRNA expression and TNF protein levels were significantly lower in Responders at the pre- LVAD implantation time point -0.07±0.01 vs 0.21±0.05 AU, p= 0.02 and 0.4±0.06 vs 0.7±0.07 pg/ml, p= 0.0012, respectively. Serum TNF protein levels, measured before the initiation of LVAD unloading, were also significantly lower in Responders - 7.8±1.1 vs 12.8±1 pg/ml, p< 0.001. Further, serum TNF levels at the pre-LVAD implantation time point were inversely correlated to the degree of change of LV ejection fraction induced by LVAD unloading (r= -0.4, p= 0.0016). Conclusion: TNF levels in myocardial tissue and serum obtained at the time of LVAD implant inversely correlate with the ability of the heart to significantly improve its endogenous function during LVAD- induced mechanical unloading. The utility of TNF as a potential biomarker to predict unloadinginduced myocardial recovery warrants further investigation.
4( 12) Percutaneous Balloon Occlusion of a Left Ventricular Assist Device Outflow Cannula During Right Heart Catheterization With Pumpstop as Part of the Evaluation of Myocardial Recovery J. Vierecke , M. Hernánedes-Enriquez, M. Dandel, M. Müller, P. Stawowy, S. Dreysse, E. Potapov, T. Krabatsch, R. Hetzer. Deutsches Herzzentrum Berlin, Berlin, Germany. Purpose: Off-pump trials to evaluate myocardial recovery in pts.supported by continuous-flow pumps might be more challenging than with pulsatile-flow devices because of retrograde flow through the left ventricular assist device (LVAD). In 2011 we described the first case of right heart catheterization with balloon occlusion during an off-pump trial. The present study aims to analyze the measurements and follow-up of right heart catheterization during percutaneous occlusion of VAD outflow cannula as part of the evaluation of weaning potential. Methods: Between 5/2006 and 11/2013 we implanted 210 HeartMate II and 412 HeartWare pumps at our center. Between 05/2011 and 08/2013 a total of 20 patients on VAD who showed weaning potential by echocardiography were evaluated by right heart catheterization during pump stop and balloon occlusion. Measurements were taken with optimal rotation of the LVAD and pump stop with the outflow graft occluded by inflating the balloon catheter. To occlude the outflow graft, different balloon catheters were used. We considered LVAD explantation to be safely possible if cardiac output, PA and PCWP remain stable in the off-pump trial with balloon occlusion. Results: A total of 20 patients received 22 off-pump trials. 80% were male. Median age was 49.5 years (min/max 24/64y). 14 patients were supported by HeartWare and 6 by Heartmate II LVAD. 6 patients were anticoagulated with refludan due to HIT II, all others were anticoagulated with heparin There were 5 pts. with increase of PCWP and PAP over 30% during ballon occlusion, 1 with only increase in PCW and 1 other with increase only in PAP. A decrease in cardiac output was seen in 5 pts., all others showed stable pressures. There were no complications or deaths related to the catheterization. 11 pts. (55%) were considered to have weaning potential. 8 were explanted and 2 others were scheduled. One is still on assist due to increased LVEDD and rhythm disturbances. Two patients died due to sepsis/infection during follow up. All explanted patients were free from heart failure recurrence (mean follow up time 20 month). Conclusion: Evaluation of weaning potential from VADs by heart catheterization during pump stop and balloon occlusion of the outflow cannula is a safe procedure and a valuable tool for guiding decisions on VAD explantation. 4( 13) Influence of MELD (Model of End-Stage Liver Disease)_XI (eXcluding INR) on Post-Heart Transplant (HT) Outcomes E.C. DePasquale , A. Nsair, L. Reardon, A. Ardehali, M. Deng. UCLA, Los Angeles, CA. Purpose: Liver dysfunction increases post-surgical morbidity and mortality. MELD-XI has been evaluated in ambulatory heart failure patients and in those receiving VAD support in a single center. We sought to evaluate MELD-XI in a national cohort. Methods: 40465 HT recipients were identified from UNOS (1987-2011) and stratified by MELD-XI score > = 17 (n= 24013) or < 17 (n= 16442) calculated using creatinine and bilirubin at time of transplant. Exclusions: age< 18, re-HT & lost to follow up, missing creatinine and bilirubin. Survival was censored at 12y. Multivariate Cox proportional hazard regression analysis was adjusted for age, sex, DM, race, ischemic time, dialysis, life support, VAD use, wait time & HLA mismatch. Results: ELD-XI > = 17 was associated with younger age (p< 0.001), less prior cardiac surgery (p< 0.001), younger donor age (p< 0.001), less VAD use (p< 0.001) and increased ventilator use (p< 0.001) with a shorter wait time (p< 0.001). MELD-XI > = 17 were more likely to be listed as status 2 (30% vs 24%, p< 0.001). Survival (1, 5 & 10y) was: MELD-XI < 17 (89, 74, 54%) & MELD-XI > = 17(81, 65, 45%) (Figure). Unadjusted HR (compared to MELD-XI < 17) for all-cause mortality was 1.35 (CI 1.31-1.40). Multivariate analysis yielded a HR of 1.40 (CI 1.35-1.45). Conclusion: Survival is significantly reduced post-HT in patients with MELD-XI > = 17. Prospective study is warranted as MELD-XI may provide insight into patient selection.