Impact of COVID-19 on Patients Supported with a Left Ventricular Assist Device.

Patients on left ventricular assist device (LVAD) support may be susceptible to severe disease and complications from coronavirus disease-19 (COVID-19). The purpose of this study was to describe the clinical course of COVID-19 in LVAD patients. A retrospective review was performed at our center; 28 LVAD patients who developed COVID-19 between March 2020 and March 2021, and six patients with a prior COVID-19 infection who underwent LVAD implantation, were identified and examined. Of the 28 patients, nine (32%) died during the study period, five (18%) during their index hospitalization for COVID-19. Two patients (7%) presented with suspected pump thrombosis. In a nonadjusted binary regression logistic analysis, admission to the intensive care unit (unadjusted odds ratio, 7.6 [CI, 1.2-48], P = 0.03), and the need for mechanical ventilation (unadjusted odds ratio 14 [CI, 1.3-159], P = 0.03) were associated with mortality. The six patients who previously had COVID-19 and subsequently received a LVAD were on intra-aortic balloon pump and inotropic support at time of surgery. All six experienced a complicated and prolonged postoperative course. Three patients (50%) suffered from ischemic stroke, and there was one (17%) 30 day mortality. We observed an increased risk of morbidity and mortality in LVAD patients with COVID-19.

Outcomes Following Left Ventricular Assist Device Exchange: Focus on the Impacts of Device Infection.

Hemodynamic support with continuous-flow left ventricular assist device (CF-LVAD) therapy has proven a reliable treatment for advanced heart failure. Although modern LVADs are highly durable, device failure and infection can be resolved with surgical exchange of pump components. In this study, we investigated the incidence and outcomes of LVAD exchange with the HeartMate II and HeartWare HVAD. Data were obtained from 677 patients who underwent CF-LVAD implantation between 2005 and 2016. Patients who underwent a device exchanged were included. The primary outcomes were length of hospital stay and mortality. Of the 677 patients included in this study, 72 (10.6%) required LVAD exchange. Thirty-day and 1-year mortality rates were comparable to primary LVAD implantation: 4.3% vs. 3.49%, p = 0.727 and 20.3% vs. 20.7%, p = 0.989, respectively. Thirty-one patients (4.5%) underwent exchange with ongoing infection. Kaplan-Meier analysis indicated significant differences in survival between groups based on indication for exchange. Patients who underwent exchange after more than 150 days of active infection suffered worse postexchange survival than those who underwent exchanged earlier (P = 0.007). While exchange was required only in 10.6% of patients undergoing LVAD implantation, our results show device exchange may be executed safely and effectively, with long-term outcomes similar to primary LVAD implantation. The indication for device exchange impacts postexchange outcomes, and those exchanged with LVAD infection tend to fare worse than those exchanged for device malfunction or thrombus. Patients who are exchanged with active infection have better postoperative survival if the exchange is performed expeditiously after medical management has failed.

Treatment of HeartMate II Short-to-Shield Patients With an Ungrounded Cable: Indications and Long-Term Outcomes.

Despite modifications and a procedure to externally replace the distal portion of the percutaneous lead, damage to the wiring insulation causing an electrical short to ground, referred to as a short to shield (STS), has become an important factor in the longevity of the HeartMate II left ventricular assist device (LVAD). Device exchange has been the suggested treatment option. The aim of this study was to evaluate the long-term clinical outcomes of patients with an STS supported on an ungrounded cable. A retrospective review of all patients (n = 479) implanted with a HeartMate II at our center between January 2008 and December 2017 was performed. Patients with a documented STS maintained on an ungrounded cable were examined. Patient characteristics, time from device implantation to STS, treatment strategies, and duration of support on an ungrounded cable were summarized. The association between support with an ungrounded cable and clinical outcomes was evaluated. A total of 53 (11% of 479) patients (83% males and 81% destination therapy) with an STS were supported on an ungrounded cable for a median duration of 195 days (range 2 days to 3.3 years). Patients were more active (New York Heart Association [NYHA] p < 0.001, 6 minute walk test [6MWT] p = 0.003) and had a trend toward increased weight gain (p = 0.055) from time of implant to STS. Duration of support before the STS was 1.9 years (range 165 days to 8.6 years). Twenty-two patients were treated directly with an ungrounded cable and 31 patients underwent an external driveline repair and still required an ungrounded cable within 2 days (range 0 days to 1.3 years). During the study period, 38 patients were maintained on an ungrounded cable: 21 patients were ongoing for 299 days (range 114 days to 2.8 years), 11 patients transplanted after 79 days (range 7-295 days), four patients died because of comorbid conditions after 1.6 years (range 141 days to 3.2 years), one patient exchanged for thrombosis after 229 days, and one patient explanted after 279 days. The other 15 patients developed a phase-to-phase electrical short after 51 days (range 2 days to 3.3 years): 14 patients underwent a successful pump exchange and one patient transplanted within 2 days. No patients died because of support with an ungrounded cable or worsening lead damage necessitating device exchange. With extended durations of support, some patients with a HeartMate II LVAD will experience device failure in the form of an STS. Select patients with an STS can be safely supported on an ungrounded cable for several years with close monitoring. This treatment approach should be considered before a device exchange.

The impact of extreme obesity on outcomes after left ventricular assist device implantation.

BACKGROUND: The association between extreme body mass index (BMI) and outcomes in left ventricular assist device (LVAD) patients has not been well established. With the commercial use of LVADs a larger number of patients with a BMI >40 have undergone device implantation. The purpose of this study was to evaluate the short and long-term outcomes of LVAD patients with extreme obesity. METHODS: A retrospective review of all patients (n=383) at our center who received a LVAD as primary implant between 2005-2015 was performed. Demographics, preoperative laboratory values, and postoperative outcomes were analyzed. Patients were divided into three groups based on BMI (kg/m2) classification (group 1: ≤25; group 2: 25 to 35; group 3: ≥35) and compared using one-way analysis of variance (ANOVA), Kruskal-Wallis and Chi-squared analysis as appropriate. RESULTS: Comparison of postoperative outcomes demonstrated an increased risk of respiratory failure and right ventricular (RV) failure in patients with a BMI ≥35 (range, 35-59). Length of stay, sternal infection, driveline/pocket infection, systemic infection, GI-bleeding, and neurological events within the first year of device therapy were not related to BMI. Survival at 30-day, 1- and 2-year was not significantly different among the three groups. The group with the smallest BMI demonstrated an increased risk for re-operative bleeding. CONCLUSIONS: Despite an increased risk of early morbidity in patients with extreme obesity, long term survival was not significantly different between the BMI groups. Careful consideration is recommended when evaluating patients with an excessive BMI for LVAD therapy although it should not be a contraindication for device placement.

Efficacy of Inpatient Rehabilitation After Left Ventricular Assist Device Implantation.

BACKGROUND: Left ventricular assist devices (LVADs) have become an increasingly popular and effective means for treating advanced heart failure. LVAD implantation requires extensive surgery and postoperative rehabilitation. The Functional Independence Measure (FIM) has been used to quantify functional gains in numerous patient populations, including those with stroke and spinal cord injury. This study investigated functional improvements in patients undergoing LVAD implantation using the FIM score. OBJECTIVE: To assess functional improvements in patients with advanced heart failure who underwent LVAD implantation. DESIGN: Retrospective. SETTING: Inpatient rehabilitation unit. SUBJECTS: Ninety consecutive patients who received acute inpatient rehabilitation after continuous flow LVAD implantation. METHODS: Demographic, laboratory, and functional outcomes data including inpatient rehabilitation unit (IRU) length of stay (LOS), discharge disposition, and FIM score were collected for all patients. Paired t-tests were used to assess change in functional measures and laboratory data. MAIN OUTCOME MEASURES: Primary outcome measures included FIM gain, FIM efficiency, discharge disposition, rates of readmission after discharge from rehabilitation, and LOS in the rehabilitation unit. RESULTS: The FIM gain was statistically significant at 28.4 ± 12.3 (P < .001) and compared favorably with benchmarks for mean FIM gains at our facility (26.4), regionally (21.5), and nationally (22.7) for patients admitted to IRUs with a cardiac diagnosis. FIM efficiency (FIM gain/IRU LOS) was 1.9 ± 1.0 compared with the mean FIM efficiency at our facility (2.2), regionally (2.1), and nationally (2.2). Seventy-four percent (n = 67) of patients were discharged directly home after inpatient rehabilitation, 17% (n = 16) were readmitted to the acute hospital service, and 8% (n = 7) required additional rehabilitation at a subacute rehabilitation facility. The IRU LOS was 16.2 ± 6.9 days. CONCLUSIONS: Our study indicates that most patients with an LVAD achieve clinically meaningful functional gains from acute inpatient rehabilitation, with the majority of patients being discharged home. Further studies need to be performed to analyze clinical outcomes after acute inpatient rehabilitation. LEVEL OF EVIDENCE: IV.

Model for end-stage liver disease predicts right ventricular failure in patients with left ventricular assist devices.

High rates of right ventricular failure continue to affect postoperative outcomes in patients implanted with left ventricular assist devices (LVADs). Development of right ventricular failure and implantation with right ventricular assist devices is known to be associated with significantly increased mortality. The model for end-stage liver disease (MELD) score is an effective means of evaluating liver dysfunction. We investigated the prognostic utility of postoperative MELD on post-LVAD implantation outcomes. MELD scores, demographic data, and outcomes including length of stay, survival, and postoperative right ventricular failure were collected for 256 patients implanted with continuous flow LVADs. Regression and Kaplan-Meier analyses were used to investigate the relationship between MELD and all outcomes. Increased MELD score was found to be an independent predictor of both right heart failure and necessity for RVAD implantation (OR 1.097, CI 1.040-1.158, p = 0.001; OR 1.121, CI 1.015, p = 0.024, respectively). Patients with RV failure and who underwent RVAD implantation had reduced postoperative survival compared to patients with RV dysfunction (no RV failure = 651.4 ± 609.8 days, RV failure = 392.6 ± 444.8 days, RVAD = 89.3 ± 72.8 days; p < 0.001). In conclusion, MELD can be used to reliably predict postoperative right heart failure and the necessity for RVAD implantation. Those patients with RV failure and RVADs experience significantly increased postoperative mortality compared to those without RV dysfunction.

Caregivers and Left Ventricular Assist Devices as a Destination, Not a Journey.

BACKGROUND: The quality of life (QOL) of caregivers of patients with LVAD-DT (Left Ventricular Assist Device as Destination Therapy) has not been well explored. METHODS: We used a concurrent mixed methods design. Caregivers (n = 42; average 60 years old, 82% female, 75% white) of patients (n = 39; average 68.3 years old, 83% male, 90% white) and providers (n = 27) from 6 LVAD-DT programs were recruited. We used the City of Hope Quality of Life Family Caregiver instrument, modified for LVAD-DT. Lower scores indicate poorer QOL. We analyzed open-ended questions with the use of Nvivo 10.0, using a modified grounded theory approach. RESULTS: The Psychologic subscale had the lowest average QOL score, followed by Social, Spiritual, and then Physical subscales. The composite mean average QOL score across the subscales was highest in caregivers <40 years of age and ≥70 years of age. There was a nonsignificant trend toward better QOL in male caregivers (P = .06). We sorted QOL items into tertiles based on the percentage of responses <5 (10-point Likert scale). Scores <5 in the 2nd tertile (items from Social and Spiritual subscales) were reported by many fewer respondents than the 1st tertile (items from the Psychologic subscale). In the 3rd tertile, <10% of respondents scored <5 on 15 of the items. In qualitative interviews psychologic and social themes predominated in discussing requisites for competent caregivers, stress in pre-implantation decision making, lack of psychologic preparation, impact on freedom/independence, daily worry about pump performance, and value of psychologic and social support. CONCLUSION: Support interventions for caregivers of patients with LVAD-DT should address the psychologic and social aspects that lead to poor QOL.

Evaluation and management of emergencies in patients with mechanical circulatory support devices.

Mechanical circulatory support devices such as ventricular assist devices have become the approved and accepted treatment option to improve survival and quality of life in patients with advanced heart failure refractory to medical therapy. Patients as a result are living longer and presenting to emergency medical services, primary care facilities, emergency departments, and critical care units more frequently. Currently, health care providers have limited experience in managing this complex patient population. Thus, we created a standardized method of initial evaluation and algorithmic approach of management to help in the management of emergencies in this unique patient population. We present a comprehensive overview of the types of mechanical assist devices, their complications, and an algorithmic approach to the emergency management in the patients with mechanical circulatory support. A systematic method is crucial in prompt and early recognition of emergencies to ensure appropriate management of these patients.

Protonolysis of [((i)PrO)TiMo5O18]3-: access to a family of TiMo5 Lindqvist type polyoxometalates.

The tetra-n-butylammonium (TBA) salts of [((i)PrO)TiMo(5)O(18)](3-) 1 and [((i)BuO)TiMo(5)O(18)](3-) 2 were prepared by hydrolysis of mixtures of (TBA)(2)[Mo(2)O(7)], (TBA)(4)α-[Mo(8)O(26)] and Ti(OR)(4) (R = (i)Pr or (i)Bu) in acetonitrile. Treatment of (TBA)(3)1 with alcohols ROH afforded primary and tertiary alkoxide derivatives [(RO)TiMo(5)O(18)](3-) (R = Me 3, (t)Bu 4), whilst aryloxides [(ArO)TiMo(5)O(18)](3-) were prepared by reacting 1 with phenols ArOH (Ar = C(6)H(4)Me-4 5, and C(6)H(4)CHO-2 6). Oxo-bridged [(µ-O)(TiMo(5)O(18))(2)](6-)7 rather than the hydroxo derivative [(HO)TiMo(5)O(18)](3-) was obtained upon hydrolysis of 1. X-Ray crystal structures of TBA salts of anions 3-7 show that titanium is six-coordinate in all cases, although titanium sites are disordered over two trans positions in 3. Mo-O bond length alternation is observed in the Mo(4)O(4) planes of 4 and 7 and in one of the two independent anions in the structure of 3. In solution, (17)O NMR spectra are consistent with the higher anionic charge compared to [Mo(6)O(19)](2-) and reveal an order of basicity for the anions [LM'Mo(5)O(18)](3-) associated with the ability of {LM'}(3+) to donate/withdraw electron density from {Mo(5)O(18)}(6-). Protonolysis reactions of 1 and 3 were slower than for tungstate analogues and the possibility of initial protonation at TiOM (M = Mo) rather than TiOR (M = W) in a proton-assisted S(N)1 mechanism for ligand exchange in [(RO)TiM(5)O(18)](3-) is discussed.

Destination therapy: one-year outcomes in patients with a body mass index greater than 30.

Left ventricular assist devices (LVADs) are slowly gaining acceptance as the treatment of choice in appropriately selected patients with end-stage heart failure who are not transplant candidates. Obesity is a well-known risk factor for increased cardiovascular morbidity and mortality, and frequently can be the reason some patients are turned down for heart transplantation. Because of this experience in transplant patients, many centers have also been reluctant to offer these patients an LVAD for destination therapy (DT). Subsequently, the 1-year outcomes of obese patients receiving LVADs for DT at our center were reviewed. Fifty-eight consecutive patients (83% men) were implanted with HeartMate XVE (n = 22) or HeartMate II (n = 36) LVAD. Patients were divided into normal (body mass index [BMI] or= 30 kg/m(2), n = 20) groups according to their BMI. Preoperatively, there were statistically significant differences (P < 0.05) between normal and obese groups in age (65.9 years vs. 54.7 years), weight (72.9 kg vs. 107.5 kg), BMI (24.1 kg/m(2) vs. 35.2 kg/m(2)), and incidence of diabetes (37% vs. 60%). At 1-year follow-up, there were no statistically significant differences (P > 0.5) between normal and obese groups: creatinine levels (1.4 vs. 1.5), New York Heart Association classification (1.2 vs. 1.6), and survival (63% vs. 65%). Our initial results demonstrate that morbidly obese patients with end-stage heart failure with a contraindication for transplant may successfully undergo implantation of an LVAD for DT.

Destination therapy: safety and feasibility of national and international travel.

Results for Destination Therapy (DT) continue to improve with advanced technology, better patient selection, and experienced clinical management. Quality of life for these patients is an important component of the overall success of DT, and traveling is becoming more common. We reviewed our experience with long-distance travel in our DT population. All patients implanted with a left ventricular assist device for DT were followed prospectively. Long-distance travel was considered to be >200 miles, one way from their homes. There were 15 patients (14 men) with an average age of 66 years (range, 30-82) who traveled a combined total of 40 long-distance trips. Four trips were international (Spain, Canada (2), and Puerto Rico), 35 within the continental U.S., and one to Hawaii. The average one way distance traveled was 925 miles with a range of 218-4256 miles. The average time away from home was 8.3 days (range, 2-30). Patients traveled by airplane (17), car (23), and one trip included a 5 day cruise. Five complications occurred: driveline trauma, delay of reentry into the United States, missed flight, red heart alarm from bearing wear, and dehydration. All patients returned home safely for routine follow-up. Long-distance travel is possible for DT patients. Anticipating potential problems and careful planning is necessary for safe national and international travel.

Utilization of acoustic signatures to identify HeartMate XVE device end-of-life.

BACKGROUND: As outcomes for destination therapy continue to improve, many patients are requiring left ventricular assist device (LVAD) exchange due to end-of-life of their LVAD. Current techniques to identify and diagnose device end-of-life issues usually require invasive testing or off-site filter dust analysis. In this study we assess a non-invasive technique using acoustic signals generated from the HeartMate XVE LVAD to potentially identify impending device end-of-life issues. METHODS: Nine patients were prospectively followed after implantation of the HeartMate XVE LVAD as destination therapy between May 2004 and July 2006. Acoustic signals were collected using an aquatic hydrophone system interfaced with a data acquisition system and a standard laptop computer. Data were collected at pre-set intervals. All data/acoustic signals were prospectively interpreted by a blinded independent reviewer skilled at interpreting acoustic signals. Acoustic data suggesting possible device failure were then correlated with clinical findings and LVAD examination at the time of device removal. RESULTS: All patients survived long enough to develop signs of impending device end-of-life. Four of 9 (44%) patients developed inflow valve incompetence, 4 (44%) were identified as having significant bearing wear, and 1 (12%) had both. All acoustically identified device issues were confirmed by standard clinical examinations and testing (echocardiography, angiography, laboratory tests and filter dust analysis). The acoustic findings were subsequently confirmed at time of device exchange. All patients ultimately had their device successfully exchanged and have continued to live with their new apparatus. CONCLUSIONS: Acoustic signal monitoring can successfully identify HeartMate XVE device end-of-life. This new method provides a low-cost, reproducible, non-invasive technique that may be used to identify possible impending device failure.