Natural history and clinical effect of aortic valve regurgitation after left ventricular assist device implantation

ObjectivesAortic valve regurgitation reduces left ventricular assist device mechanical efficiency. Evidence has also suggested that left ventricular assist device implantation can induce or exacerbate aortic valve regurgitation. However, this has not been compared with aortic valve regurgitation progression in a nonsurgical end-stage heart failure population. Furthermore, its clinical effect is unclear. We sought to characterize the development and progression of aortic valve regurgitation in left ventricular assist device recipients and to identify its clinical effect.MethodsA review of all consecutive patients who received an intracorporeal left ventricular assist device at Duke University Medical Center from January 2004 to January 2011 was conducted. Cases of previous or concomitant aortic valve surgery were excluded. Data from the remaining implants (n = 184) and a control group of contemporaneous nonsurgical patients with end-stage heart failure (n = 132) were analyzed. Serial transthoracic echocardiography was used to characterize aortic valve regurgitation as a function of time.ResultsLeft ventricular assist device implantation was associated with worsening aortic valve regurgitation, defined as an increase in aortic valve regurgitation grade, relative to the nonsurgical patients with end-stage heart failure (P < .0001). The recipients of continuous flow left ventricular assist devices were more likely than recipients of pulsatile left ventricular assist devices to develop worsening aortic valve regurgitation (P = .0348). Moderate or severe aortic valve regurgitation developed in 21 left ventricular assist device recipients; this was unrelated to the type of device implanted (continuous vs pulsatile; P = .754) or aortic valve regurgitation grade before left ventricular assist device implantation (P = .42). Five patients developed severe aortic valve regurgitation; all of whom underwent aortic valve procedures.ConclusionsNative aortic valve regurgitation developed and/or progressed after left ventricular assist device implantation, with this effect being more pronounced in continuous flow left ventricular assist device recipients. However, the preoperative aortic valve regurgitation grade failed to correlate with the development of substantial aortic valve regurgitation after left ventricular assist device implantation. After left ventricular assist device implantation, aortic valve regurgitation had a small, but discernible, clinical effect, with some patients developing severe aortic valve regurgitation and requiring aortic valve procedures. These data have implications for the long-term management of left ventricular assist device recipients, in particular as the durability of implantable continuous flow left ventricular assist device therapy improves

Improved outcomes in the treatment of post-myocardial infarction ventricular septal defect with percutaneous TandemHeart left ventricular mechanical circulatory support

Background Post-myocardial infarction (MI) ventricular septal defect (VSD) is associated with 40% - 50% of peri-procedural mortalities; however, it is amenable to catheter-based therapies. We retrospectively investigated the impact of state-of-the-art bridging percutaneous left ventricular mechanical circulatory support (MCS) using the TandemHeart® (TH) ventricular assist device (VAD) on a patient with post-MI VSD. Results From July 2008 to March 2014, 23 patients were referred for treatment of post-MI VSD. Initially, 18/23 patients required MCS; 12 received an intra-aortic balloon pump (IABP), while 6 received initial TH support. Seven of the IABP patients later required TH support. Catheter-based device VSD closure was performed in 18 of the patients; however, three patients required conversion to conventional open cardiac surgical repair via VSD patch closure due to failure of the catheter-based approach. Five patients with TH underwent planned open cardiac surgical repair due to an anticipated lack of suitability for catheter-based treatment. Results revealed that delayed closure after MI correlated with improved survival. Overall, 30-day and 6-month survival rates were 83% (19/23) and 70% (16/23), respectively. Conclusions Further, Qp/Qs ratios of \u3c2.4 correlated with successful percutaneous VSD repair, and this assessment should be further explored as an assessment to inform clinical judgment in patients with post-MI VSD treatment

Ribp, a Novel Rlk/Txk- and Itk-Binding Adaptor Protein That Regulates T Cell Activation

A novel T cell–specific adaptor protein, RIBP, was identified based on its ability to bind Rlk/Txk in a yeast two-hybrid screen of a mouse T cell lymphoma library. RIBP was also found to interact with a related member of the Tec family of tyrosine kinases, Itk. Expression of RIBP is restricted to T and natural killer cells and is upregulated substantially after T cell activation. RIBP-disrupted knockout mice displayed apparently normal T cell development. However, proliferation of RIBP-deficient T cells in response to T cell receptor (TCR)-mediated activation was significantly impaired. Furthermore, these activated T cells were defective in the production of interleukin (IL)-2 and interferon γ, but not IL-4. These data suggest that RIBP plays an important role in TCR-mediated signal transduction pathways and that its binding to Itk and Rlk/Txk may regulate T cell differentiation

Impact of left ventricular assist device implantation on mitral regurgitation: An analysis from the MOMENTUM 3 trial

BACKGROUND: Mitral regurgitation (MR) determines pathophysiology and outcome in advanced heart failure. The impact of left ventricular assist device (LVAD) placement on clinically significant MR and its contribution to long-term outcomes has been sparsely evaluated. METHODS: We evaluated the effect of clinically significant MR on patients implanted in the MOMENTUM 3 trial with either the HeartMate II (HMII) or the HeartMate 3 (HM3) at 2 years. Clinical significance was defined as moderate or severe grade MR determined by site-based echocardiograms. RESULTS: Of 927 patients with LVAD implants without a prior or concomitant mitral valve procedure, 403 (43.5%) had clinically significant MR at baseline. At 1-month of support, residual MR was present in 6.2% of patients with HM3 and 14.3% of patients with HMII (relative risk = 0.43; 95% CI, 0.22-0.84; p = 0.01) with a low rate of worsening at 2 years. Residual MR at 1-month post-implant did not impact 2-year mortality for either the HM3 (hazard ratio [HR],1.41; 95% CI, 0.52-3.89; p = 0.50) or HMII (HR, 0.91; 95% CI, 0.37-2.26; p = 0.84) LVAD. The presence or absence of baseline MR did not influence mortality (HM3 HR, 0.86; 95% CI, 0.56-1.33; p = 0.50; HMII HR, 0.81; 95% CI, 0.54-1.22; p = 0.32), major adverse events or functional capacity. In multivariate analysis, severe baseline MR (p = 0.001), larger left ventricular dimension (p = 0.002), and implantation with the HMII instead of the HM3 LVAD (p = 0.05) were independently associated with an increased likelihood of persistent MR post-implant. CONCLUSIONS: Hemodynamic unloading after LVAD implantation improves clinically significant MR early, sustainably, and to a greater extent with the HM3 LVAD. Neither baseline nor residual MR influence outcomes after LVAD implantation