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641 Implantable Cardioverter Defibrillator Does Not Confer Additional Survival Benefit after Placement of a Left Ventricular Assist Device
Abstracts Methods and Materials: LV apexes were obtained from patients with endstage HF (mean CI 1.5⫾0.3 l/min/m2) at the time of HMII implantation. Tissue was snap frozen at -80°C. After fixation, sections were incubated overnight with primary rabbit NET antibody at 1:100 concentrations. Biotinylated secondary antibody at 4°C against rabbit IgG was applied. Avidin-biotin peroxidase complex was used to label the secondary antibody. The perioxidase was developed using nickel-enhanced diaminobenzidine to produce different colorimetric layers. Images were captured digitally and analysed by two independent observes using analySIS software. NET immunoreactivity was calculated as the average percentage area covered from randomly selected 5 different regions. Results: 16 patients (14 males) were studied. 11 had recovered and had their LVAD explanted. Intraclass correlation coefficient between both observers revealed moderate reliability of 45.8% (R⫽ 0.464, P⫽0.028).Percentage NET immunoreactive nerve fibers per area were significantly higher in recovered patients at the time of implantation (1.04⫾0.30% vs 0.65⫾0.43%, P⫽0.05). There was a moderate correlation between NET immunoreactive nerve fibers and myocardial recovery (R⫽0.512, P⫽0.035). Conclusions: Patients recovered with LVAD support had higher percentage of NET immunoreactive nerve fibers per total area in the LV apex at the time of implantation. Immunostaining evaluation of NET immunoreactive nerve fibers may predict myocardial recovery. 639 Direct Comparison of the Performance Characteristics of the Thoratec HeartMate II, Heartware HVAD and Jarvik 2000 Left Ventricular Assist Devices A. Schmidt,1 C.T. Bowles,2 M. Noor,2 N.R. Banner,2 K.H. Parker,1 A. Simon.2 1Bioengineering, Imperial College London, London, United Kingdom; 2Transplant Unit, Harefield Hospital, Harefield, Middx., United Kingdom. Purpose: A fundamental characteristic of rotary blood pumps operating at a particular speed is the inverse relationship between the LVAD pressure differential (aortic minus left ventricular pressure) and the LVAD blood flow (i.e. the H/Q curve). However, published data which are derived from different operating conditions, neither allow direct comparison of different devices nor reflect the pulsatile component of LVAD flow induced by left ventricular function. The aim of this study was to derive steady (continuous) flow and clinically representative pulsatile flow H/Q curves for three rotary LVAD designs under standardised operating conditions. Methods and Materials: A left heart mock circulation model was constructed in which variable left ventricular (LV) function could be simulated using a pulsatile pump with the test device configured representatively. Results: Under steady flow, the HMII, HVAD and Jarvik 2000 (operating at typical pump speeds of 9K, 3K and 11K, respectively) were associated with flow increases of 186, 84 and 62.5 ml per min per mmHg decrease of LVAD pressure differential, respectively. Simulated LV contraction gave rise to anticlockwise H/Q loops where LV systole was associated with a fall in LVAD pressure differential which preceded the flow surge through the LVAD. LV diastole gave rise to an H/Q value similar to the steady flow condition. For all devices, the area within the H/Q loop increased with LV stroke volume. Higher peak flows were observed for the HMII and HVAD than the Jarvik 2000. Conclusions: The detailed behaviour of these LVADs vary markedly which has important implications for the LV/LVAD interaction and the effects of cardiovascular medication. These differences imply variability in the suitability of these devices for bridging to recovery where the LV/ LVAD interaction is believed to be of particular importance. 640 Poor Pre-Operative Pulmonary Function Tests (PFT) Do Not Predict Worse Outcomes in Patients Undergoing LVAD Placement F. Kamdar, D. Nieto, P. Eckman, M. Colvin-Adams, K. Liao, R. John. University of Minnesota, Minneapolis, MN. Purpose: Poor preoperative pulmonary function has been identified as a risk factor for poor outcomes following cardiac surgery, but this has not been well described in patients undergoing LVAD placement. The objec-
S213 tive is to examine the relationship between preoperative pulmonary function and outcomes after LVAD implantation. Methods and Materials: We evaluated patients who underwent HeartMate II implantation as BTT at a single center from 10/2005 to 5/2010. Moderate to severe obstructive pulmonary disease was defined as a forced expiratory volume in 1s (FEV1)to forced vital capacity ratio (FEV1/FVC) ⬍0.7 and FEV1 ⬍80% predicted based on PFTs. Results: 100 patients were evaluated; of these, 74 had preoperative PFTs and in 26 PFTs were deferred. Of these 74 patients, 18 had moderate to severe pulmonary disease (group 1) and 56 had normal to mild obstructive pulmonary disease (group 2). The mean FEV1 was 2.0 ⫾0.6 L in group 1 and 2.4 ⫾0.8 L (p ⫽ 0.03). The FEV1/FVC ratio was 0.59 ⫾0.08 in group 1 and 0.79 ⫾0.05 in group 2 (p ⫽ 0.001). There were no significant differences in etiology, age, and history of smoking between the two groups; however, in group 1 there were significantly more men (17 vs 38, p ⫽ 0.02) and a prior history of COPD (9 vs 4, p ⫽ 0.001). There was no significant difference in need for preoperative mechanical ventilation (MV) (1 vs 3, p ⫽0.68), mean duration of MV post-implant (1.8 ⫾1.5 days vs 3.8⫾ 10 days p ⫽ 0.16), right heart failure (0 vs 5, p ⫽ 0.33), or duration of LVAD support (305 ⫾162 days vs 375 ⫾316 days p ⫽ 0.22) between patients in both groups. Actuarial survival at 6 months was 88.8% in group 1 and 85.1% in group 2 (p ⫽ 0.42). Conclusions: Patients with moderate to severe obstruction on pre-op PFTs prior to LVAD placement do not have worse outcomes than those patients with normal PFTs. In patients with end-stage heart failure poor pulmonary function may be a reflection of decompensated heart failure, thereby suggesting that these patients would benefit from LVAD placement. 641 Implantable Cardioverter Defibrillator Does Not Confer Additional Survival Benefit after Placement of a Left Ventricular Assist Device B.A. Boilson,1J.A. Schirger,1 T. Hasin,1 Y. Topislky,1 N.L. Pereira,1 A.L. Clavell,1 P.A. Friedman,1 S.J. Park,2 S.S. Kushwaha.1 1Division of Cardiovascular Diseases, Mayo Clinic, Rochester, MN; 2Department of Cardiac Surgery, Mayo Clinic, Rochester, MN. Purpose: Implantable cardiac defibrillators (ICD) reduce mortality in ischemic and non-ischemic cardiomyopathy. However, it is unclear whether ICD implanted in left ventricular assist device (LVAD) recipients further improves survival or quality of life. In this retrospective single center study, we evaluated the effect of combined ICD therapy in LVAD recipients on outcomes and survival. Methods and Materials: Clinical, laboratory, echocardiographic and hemodynamic data were examined in patients receiving an LVAD as bridge to transplant or destination therapy between February 2007 and April 2010. Data before and after LVAD implantation was examined. Three groups were generated – no ICD, active ICD, and inactive ICD in situ post LVAD implant. Results: Of 95 patients included for study, 80 had ICDs, but only 14 had therapies active after LVAD implantation. The remaining 15 patients had no ICDs post LVAD placement. The median follow up uncensored by transplantation was 429 days. At the end of the first year, the survival rate, not censored for transplantation, was 82.1% for the inactive ICD group and 57.1% for the active ICD group. For the no-ICD group, survival rate was 86.7% at one year (inactive vs. no ICD p⫽0.88, active vs. no ICD p⫽0.12, inactive vs. active p⫽0.16). Followup duration censored by transplantation or death was 254 days. One year survival censored by transplantation or death was 78.8% for the inactive ICD group and 42.9% for the active ICD group. For the no-ICD group, overall cumulative survival rate was 86.7% at one year (inactive vs. no ICD p⫽0.71, active vs. no ICD p⫽0.64, inactive vs. active p⫽0.58). Conclusions: In this small single center study, the presence of an active ICD did not improve survival of LVAD recipients at one year post LVAD implant. These findings merit further investigation in the light of recent data suggesting that ICD shock burden may adversely affect survival. 642 Mechanical Circulatory Support in Dialysis Patients A.J. Boyle,1 M.A. Savitt,2 N.Z. Sulemanjee,1 T.E. Hastings,1 J.D. Crouch,2 G.V. Warren,3 J.D. Wallach,3 K. Nagendran,1 M.E. Anigbogu,1 F.X. Downey.2 1Cardiology, Aurora St. Luke’s Medical
S213 tive is to examine the relationship between preoperative pulmonary function and outcomes after LVAD implantation. Methods and Materials: We evaluated patients who underwent HeartMate II implantation as BTT at a single center from 10/2005 to 5/2010. Moderate to severe obstructive pulmonary disease was defined as a forced expiratory volume in 1s (FEV1)to forced vital capacity ratio (FEV1/FVC) ⬍0.7 and FEV1 ⬍80% predicted based on PFTs. Results: 100 patients were evaluated; of these, 74 had preoperative PFTs and in 26 PFTs were deferred. Of these 74 patients, 18 had moderate to severe pulmonary disease (group 1) and 56 had normal to mild obstructive pulmonary disease (group 2). The mean FEV1 was 2.0 ⫾0.6 L in group 1 and 2.4 ⫾0.8 L (p ⫽ 0.03). The FEV1/FVC ratio was 0.59 ⫾0.08 in group 1 and 0.79 ⫾0.05 in group 2 (p ⫽ 0.001). There were no significant differences in etiology, age, and history of smoking between the two groups; however, in group 1 there were significantly more men (17 vs 38, p ⫽ 0.02) and a prior history of COPD (9 vs 4, p ⫽ 0.001). There was no significant difference in need for preoperative mechanical ventilation (MV) (1 vs 3, p ⫽0.68), mean duration of MV post-implant (1.8 ⫾1.5 days vs 3.8⫾ 10 days p ⫽ 0.16), right heart failure (0 vs 5, p ⫽ 0.33), or duration of LVAD support (305 ⫾162 days vs 375 ⫾316 days p ⫽ 0.22) between patients in both groups. Actuarial survival at 6 months was 88.8% in group 1 and 85.1% in group 2 (p ⫽ 0.42). Conclusions: Patients with moderate to severe obstruction on pre-op PFTs prior to LVAD placement do not have worse outcomes than those patients with normal PFTs. In patients with end-stage heart failure poor pulmonary function may be a reflection of decompensated heart failure, thereby suggesting that these patients would benefit from LVAD placement. 641 Implantable Cardioverter Defibrillator Does Not Confer Additional Survival Benefit after Placement of a Left Ventricular Assist Device B.A. Boilson,1J.A. Schirger,1 T. Hasin,1 Y. Topislky,1 N.L. Pereira,1 A.L. Clavell,1 P.A. Friedman,1 S.J. Park,2 S.S. Kushwaha.1 1Division of Cardiovascular Diseases, Mayo Clinic, Rochester, MN; 2Department of Cardiac Surgery, Mayo Clinic, Rochester, MN. Purpose: Implantable cardiac defibrillators (ICD) reduce mortality in ischemic and non-ischemic cardiomyopathy. However, it is unclear whether ICD implanted in left ventricular assist device (LVAD) recipients further improves survival or quality of life. In this retrospective single center study, we evaluated the effect of combined ICD therapy in LVAD recipients on outcomes and survival. Methods and Materials: Clinical, laboratory, echocardiographic and hemodynamic data were examined in patients receiving an LVAD as bridge to transplant or destination therapy between February 2007 and April 2010. Data before and after LVAD implantation was examined. Three groups were generated – no ICD, active ICD, and inactive ICD in situ post LVAD implant. Results: Of 95 patients included for study, 80 had ICDs, but only 14 had therapies active after LVAD implantation. The remaining 15 patients had no ICDs post LVAD placement. The median follow up uncensored by transplantation was 429 days. At the end of the first year, the survival rate, not censored for transplantation, was 82.1% for the inactive ICD group and 57.1% for the active ICD group. For the no-ICD group, survival rate was 86.7% at one year (inactive vs. no ICD p⫽0.88, active vs. no ICD p⫽0.12, inactive vs. active p⫽0.16). Followup duration censored by transplantation or death was 254 days. One year survival censored by transplantation or death was 78.8% for the inactive ICD group and 42.9% for the active ICD group. For the no-ICD group, overall cumulative survival rate was 86.7% at one year (inactive vs. no ICD p⫽0.71, active vs. no ICD p⫽0.64, inactive vs. active p⫽0.58). Conclusions: In this small single center study, the presence of an active ICD did not improve survival of LVAD recipients at one year post LVAD implant. These findings merit further investigation in the light of recent data suggesting that ICD shock burden may adversely affect survival. 642 Mechanical Circulatory Support in Dialysis Patients A.J. Boyle,1 M.A. Savitt,2 N.Z. Sulemanjee,1 T.E. Hastings,1 J.D. Crouch,2 G.V. Warren,3 J.D. Wallach,3 K. Nagendran,1 M.E. Anigbogu,1 F.X. Downey.2 1Cardiology, Aurora St. Luke’s Medical