Acoustic Properties of Axial and Centrifugal Flow Left Ventricular Assist Devices and Prediction of Pump Thrombosis.

OBJECTIVE: To characterize the properties of the audible tones produced by current left ventricular assist device (LVAD) pumps approved for use, and to ascertain if changes in those may be present in the setting of pump thrombosis. PATIENTS AND METHODS: From August 31, 2016, to January 16, 2020, LVAD recipients consented to have surface recordings obtained using a high-fidelity digital stethoscope. Audio data were analyzed using digital recording and editing software to produce an acoustic spectrogram by Fast Fourier transformation. RESULTS: Recordings were obtained in 53 patient encounters (27 HeartMate II, 19 HeartWare and 7 HeartMate 3). In 12 patients (9 HeartMate II, 3 HeartWare) there was a clinical concern for pump thrombosis. In all patients and pump models, a fundamental frequency was noted, and the second and third harmonics were also clearly detectable. Where thrombosis occurred in the HeartMate II pump, the absolute (normal -46.9 [-57.5,-42.9] dB vs thrombosis -41.4 [-49.8,-26.8] dB; P=.08) and relative (normal 0.72 [0.62, 0.92] vs thrombosis 0.95 [0.86, 1.24]; P=.01) third harmonic frequencies were increased in amplitude. Where paired data were available, an increase in the absolute and relative third harmonic frequencies was observed in all patients. In the case of the HeartWare device, a consistent difference in harmonic amplitudes in the setting of thrombosis could not be identified. CONCLUSION: A consistent pattern of fundamental and harmonic frequencies is common to all LVADs currently approved for use. Alterations in the amplitude of higher order harmonics may signal the onset of pump thrombosis in axial flow LVADs.

Ventricular tachycardia and preload deficiency post LVAD - The importance of integrated assessment.

Ventricular tachycardia (VT) is common in LVAD recipients, and although often well tolerated, may result in symptoms and ICD therapies, and therefore require further evaluation and treatment. However, preload deficiency may also contribute to the development of ventricular tachycardia after LVAD implantation by provoking inflow cannula related VT. In this report, three cases are described where ventricular tachycardia was evaluated by integrated assessment utilizing echo and the HeartWare HVAD console, and successfully treated by modification of LV loading conditions.

Palliative Medicine and Preparedness Planning for Patients Receiving Left Ventricular Assist Device as Destination Therapy-Challenges to Measuring Impact and Change in Institutional Culture.

CONTEXT: Although left ventricular assist devices as destination therapy (DT-LVAD) can improve survival, quality of life, and functional capacity in well-selected patients with advanced heart failure, there remain unique challenges to providing quality end-of-life care in this population. Palliative care involvement is universally recommended, but how to best operationalize this care and measure success is unknown. OBJECTIVES: To characterize the process of preparedness planning (PP) for patients receiving DT-LVAD at our institution and better understand opportunities for quality improvement or procedural transferability. METHODS: Retrospective review of 107 consecutive patients undergoing DT-LVAD implantation at a single institution between 2009 and 2013. Information regarding demographics, advance care planning, and mortality was abstracted from the medical record and analyzed. Findings were compared with a historical cohort who received DT-LVAD implantation at the same institution before the development of PP (2003-2009). RESULTS: Mean age of patients receiving DT-LVAD was 64.3 years (SD ± 10.7). At last follow-up, 46 patients (43%) had died. Mean post-DT-LVAD survival in this group was 1.1 years (SD ± 1.2). Eighty-nine percent of patient had palliative care consultation before implantation, and 70% completed PP. Although 66% of patients completed an advance directive (AD) preimplantation, only two ADs (2.8%) specifically mentioned DT-LVAD and none addressed core elements of PP. AD completion rates improved from 47% before our policy on PP (P = 0.012). CONCLUSION: A disconnect was evident between the rigor of PP discussions and the content of ADs in the medical record. We urge that future efforts focus on narrowing this gap.

Dying With a Left Ventricular Assist Device as Destination Therapy.

BACKGROUND: Despite the ability of left ventricular assist device as destination therapy (DT-LVAD) to prolong survival for many patients with advanced heart failure, little is known about the eventual end-of-life care that patients with DT-LVAD receive. METHODS AND RESULTS: All patients undergoing DT-LVAD at the Mayo Clinic in Rochester, Minnesota, from January 1, 2007, to September 30, 2014, who subsequently died before July 1, 2015, were included. Information about end-of-life care was obtained from documentation in the electronic medical record. Of 89 patients who died with a DT-LVAD, the median (25th-75th percentile) time from left ventricular assist device implantation to death was 14 (4-31) months. The most common causes of death were multiorgan failure (26%), hemorrhagic stroke (24%), and progressive heart failure (21%). Nearly half (46%) of the patients saw palliative care within 1 month before death; however, only 13 (15%) patients enrolled in hospice a median 11 (range 1-315) days before death. Most patients (78%) died in the hospital, of which 88% died in the intensive care unit. In total, 49 patients had their left ventricular assist device deactivated before death, with all but 3 undergoing deactivation in the hospital. Most patients died within an hour of left ventricular assist device deactivation and all within 26 hours. CONCLUSIONS: In contrast to the general heart failure population, most patients with DT-LVAD die in the hospital and few use hospice. Further work is needed to understand these differences and to determine whether patients with DT-LVAD are receiving optimal end-of-life care.