Caregiver burden before heart transplantation and long-term mechanical circulatory support: Findings from the sustaining quality of life of the aged: Transplant or mechanical support (SUSTAIN-IT) study

BACKGROUND

Caregiving for heart failure (HF) patients is burdensome. We examined differences in caregiver burden for 3 groups of older advanced HF patients: (1) supported with mechanical circulatory support (MCS) before heart transplantation (HT MCS), (2) awaiting transplant without MCS (HT non-MCS), and (3) prior to long-term MCS and factors associated with burden.

METHOD

From October 1, 2015 to December 31, 2018, we enrolled 276 caregivers for HF patients from 13 U.S. sites: 85 HT MCS, 96 HT non-MCS, and 95 prior to long-term MCS. At enrollment, caregivers completed the Oberst Caregiving Burden Scale (15 items, 2 subscales: time (range = 1-5; higher score = more time spent on task) and difficulty (range = 1-5; higher score = higher difficulty of task) and other measures. Statistical analyses included descriptive statistics, ANOVA, chi-square tests, and linear regression.

RESULT

Overall, caregivers were aged 60.8 ± 9.8 years and predominantly white, female, spouses, well educated, and reported ≥1 comorbidities. Caregivers overall reported a moderate amount of time spent on tasks and slight task difficulty. Caregivers for HT non-MCS candidates reported significantly less perceived time spent on tasks than caregivers for HT MCS candidates and caregivers for patients prior to long-term MCS (2.2 ± 0.74 vs 2.4 ± 0.74 vs 2.5 ± 0.71, respectively, p = 0.02) and less perceived difficulty of tasks (1.2 ± 0.33 vs 1.4 ± 0.53 vs 1.4 ± 0.54, respectively, p = 0.01). Caregiver and patient factors were associated with caregiver burden.

CONCLUSIONS

Prior to HT and long-term MCS, caregiver burden was low to moderate. Caregiver factors were predominantly associated with caregiver burden. Understanding caregiver burden and factors affecting caregiver burden may enhance preoperative advanced therapies discussions and guide caregiver support.

State of the art - Extracorporeal membrane oxygenation as a bridge to thoracic transplantation

BACKGROUND

Extracorporeal membrane oxygenation (ECMO) has revolutionized the treatment of refractory cardiac and respiratory failure, and its use continues to increase, particularly in adults. However, ECMO-related morbidity and mortality remain high.

MAIN TEXT

In this review, we investigate and expand upon the current state of the art in thoracic transplant and extracorporeal life support (ELS). In particular, we examine recent increase in incidence of heart transplant in patients supported by ECMO; the potential changes in patient care and selection for transplant in the years prior to updated United Network for Organ Sharing (UNOS) organ allocation guidelines versus those in the years following, particularly where these guidelines pertain to ECMO; and the newly revived practice of heart-lung block transplants (HLT) and the prevalence and utility of ECMO support in patients listed for HLT.

CONCLUSIONS

Our findings highlight encouraging outcomes in patients bridged to transplant with ECMO, considerable changes in treatment surrounding the updated UNOS guidelines, and complex, diverse outcomes among different centers in their care for increasingly ill patients listed for thoracic transplant.

Preoperative hemodynamics as predictors of right heart failure post-left ventricular assist device

Background

Mechanical circulatory support has garnered significant popularity as both a bridge to transplant as well as a destination therapy for patients with end-stage heart failure. Right heart failure (RHF) is a devastating complication after LVAD placement and is very unpredictable. Assisted circulation of the left ventricle (LV) with an LVAD device could unmask an underlying RHF. However, otherwise healthy right ventricles (RVs) can develop RHF after LVAD placement as well due to poor adaptation to new filling pressures and altered hemodynamics. It has been proposed that preoperative volumetric measurements in the pulmonary and systemic vasculature may serve as indicators for a risk of RHF after LVAD implantation. The aim of this study is to examine a potential relationship of preoperative hemodynamic values such as pulmonary artery pulsatility index (PAPi) and the ratio of central venous pressure to pulmonary wedge pressure (CVP/PWP) as preoperative predictors for RHF post LVAD placement.

Methods

We retrospectively reviewed patients undergoing initially planned isolated LVAD implantation with or without concomitant procedures in our institution from January 1, 2017 to June 12, 2020. Data were gathered from hemodynamic records, echocardiographic interpretations, and clinical notes. Patients who had RHF after LVAD implantation but without hemodynamic data available within 14 days from the operation were excluded. Univariable analysis was performed.

Results

Of the 114 patients who received planned isolated LVAD surgery, 70 (61.4%) experienced RHF within the first 7 days postoperatively. PAPi did not correlate significantly with RHF vs non-RHF among LVAD recipients (3.1 ± 2.1 vs. 3.8 ± 3.4 P = 0.21). Pre-op CVP/PWP did not differ significantly between RHF and non-RHF patients (0.4 ± 0.2 vs. 0.5 ± 0.8 P = 0.28). There was a nonsignificant correlation between elevated pre-op PWP and those with RHF vs those without, OR = 1.05 (95% CI: 1.00, 1.10). Pre-op systolic pulmonary artery pressure (SysPAP) was elevated in patients with post-LVAD RHF compared to those without (51.3 ± 12.3 vs. 47.2 ± 13.0, P = 0.09).

Conclusion

Preoperative hemodynamic variables such as PAPi or CVP/PWP did not show a significant correlation predicting RHF post LVAD implantation. Acute RHF post LVAD implantation remains a complex medical entity. Several studies have devised multivariable risk scores; however, their performance has been limited. Despite the widespread use of preoperative hemodynamics measurements as risk scores, our study suggests these scores are not as accurate as their use would suggest, particularly among especially morbid patient populations. More prospective studies are needed to accurately demonstrate how preoperative hemodynamics could predict and help prevent this catastrophic complication.

Systemic arterial pulsatility index (SAPi) predicts adverse outcomes in advanced heart failure patients

Ventriculo-arterial (VA) coupling has been shown to have physiologic importance in heart failure (HF). We hypothesized that the systemic arterial pulsatility index (SAPi), a measure that integrates pulse pressure and a proxy for left ventricular end-diastolic pressure, would be associated with adverse outcomes in advanced HF. We evaluated the SAPi ([systemic systolic blood pressure-systemic diastolic blood pressure]/pulmonary artery wedge pressure) obtained from the final hemodynamic measurement in patients randomized to therapy guided by a pulmonary arterial catheter (PAC) and with complete data in the Evaluation Study of Congestive Heart Failure and Pulmonary Artery Catheterization Effectiveness (ESCAPE) trial. Cox proportional hazards regression was performed for the outcomes of (a) death, transplant, left ventricular assist device (DTxLVAD) or hospitalization, (DTxLVADHF) and (b) DTxLVAD. Among 142 patients (mean age 56.8 ± 13.3 years, 30.3% female), the median SAPi was 2.57 (IQR 1.63-3.45). Increasing SAPi was associated with significant reductions in DTxLVAD (HR 0.60 per unit increase in SAPi, 95% CI 0.44-0.84) and DTxLVADHF (HR 0.81 per unit increase, 95% CI 0.70-0.95). Patients with a SAPi ≤ 2.57 had a marked increase in both outcomes, including more than twice the risk of DTxLVAD (HR 2.19, 95% CI 1.11-4.30) over 6 months. Among advanced heart failure patients with invasive hemodynamic monitoring in the ESCAPE trial, SAPi was strongly associated with adverse clinical outcomes. These findings support further investigation of the SAPi to guide treatment and prognosis in HF undergoing invasive hemodynamic monitoring.

The Impact of Adverse Events on Functional Capacity and Quality of Life After HeartWare Ventricular Assist Device Implantation

Left ventricular assist devices (LVADs) improve quality of life (QoL) and functional capacity (FC) for patients with advanced heart failure. The association between adverse events (AEs) and changes in QoL and FC are unknown. Patients treated with the HeartWare ventricular assist device (HVAD) with paired 6-minute walk distance (6MWD, n = 263) and Kansas City Cardiomyopathy Questionnaires (KCCQ, n = 272) at baseline and 24 months in the ENDURANCE and ENDURANCE Supplemental Trial databases were included. Patients were stratified based upon occurrence of clinically significant AEs during the first 24 months of support and analyzed for the mean change in 6MWD and KCCQ. The impact of AE frequency on change in 6MWD and KCCQ from baseline to 24 months was evaluated. Of the AEs examined, only sepsis was associated with an improvement in 6MWD (109 m vs. 16 m, p = 0.002). Patients without improvement in 6MWD test from baseline to 24 months had significantly more AEs than those with FC improvement (p = 0.0002). Adverse events did not affect the KCCQ overall summary score. In this analysis, patients with fewer AEs had greater improvement in FC during the 24-month follow up. The frequency of AEs did not have a significant impact on QoL after LVAD implantation.

Pedicle flap coverage for infected ventricular assist device augmented with dissolving antibiotic beads: Creation of an antibacterial pocket

Infectious complications following left ventricular assist device implantation can carry significant morbidity and mortality. The main tenet of treatment is source control which entails local wound care, intravenous antimicrobial therapy, surgical debridement, and at times, soft tissue flap coverage. The mode of therapy depends on the severity, etiology, and location of infection as well as the clinical status of the patient. We describe a case of a 46-year-old male who underwent left ventricular assist device placement complicated by pump thrombosis, recurrent infection, and hardware exposure who was successfully treated with a novel method of staged, soft tissue reconstruction.

INTERMACS profiles and outcomes of ambulatory advanced heart failure patients: A report from the REVIVAL Registry

BACKGROUND

Ambulatory patients with advanced heart failure (HF) are often considered for advanced therapies, including durable mechanical circulatory support (MCS). The Interagency Registry for Mechanically Assisted Circulatory Support (INTERMACS) profiles are a commonly used descriptor of disease severity in patients receiving MCS devices, but their role in defining the prognosis of ambulatory patients is less well established, especially for Profiles 6 and 7.

METHODS

Registry Evaluation of Vital Information on Ventricular Assist Devices in Ambulatory Life is a prospective observational study of 400 outpatients from 21 MCS and cardiac transplant centers. Eligible patients had New York Heart Association Class II to IV symptoms despite optimal medical and electrical therapies with a recent HF hospitalization, heart transplant listing, or evidence of high neurohormonal activation.

RESULTS

The cohort included 33 INTERMACS Profile 4 (8%), 83 Profile 5 (21%), 155 Profile 6 (39%), and 129 Profile 7 (32%). Across INTERMACS profiles, there were no differences in age, gender, ejection fraction, blood pressure, or use of guideline-directed medical therapy. A lower INTERMACS profile was associated with more hospitalizations, greater frailty, and more impaired functional capacity and quality of life. The composite end point of death, durable MCS, or urgent transplant at 12 months occurred in 39%, 27%, 24%, and 14% subjects with INTERMACS Profiles 4, 5, 6, and 7, respectively (p = 0.004).

CONCLUSIONS

Among ambulatory patients with advanced HF, a lower INTERMACS profile was associated with a greater burden of HF across multiple dimensions and a higher composite risk of durable MCS, urgent transplant, or death. These profiles may assist in risk assessment and triaging ambulatory patients to advanced therapies.

Mind-Body Interventions for Individuals With Heart Failure: A Systematic Review of Randomized Trials

BACKGROUND

The effects of mind-body interventions (MBIs) (eg, Tai Chi, yoga, meditation) for individuals with heart failure (HF) have not been systematically evaluated.

METHODS AND RESULTS

We performed a systematic review of randomized controlled trials (RCTs) examining the effects of MBIs in HF. We extracted participant characteristics, MBI procedure, outcomes assessed, and main results of English-language RCTs before October 2016. We identified 24 RCTs (n = 1314 participants) of 9 MBI types: Tai Chi (n = 7), yoga (n = 4), relaxation (n = 4), meditation (n = 2), acupuncture (n = 2), biofeedback (n = 2), stress management (n = 1), Pilates (n = 1), and reflexology (n = 1). Most (n = 22, 95.8%) reported small-to-moderate improvements in quality of life (14/14 studies), exercise capacity (8/9 studies), depression (5/5 studies), anxiety and fatigue (4/4 studies), blood pressure (3/5 studies), heart rate (5/6 studies), heart rate variability (7/9 studies), and B-type natriuretic peptide (3/4 studies). Studies ranged from 4 minutes to 26 weeks and group sizes ranged from 8 to 65 patients per study arm.

CONCLUSIONS

Although wide variability exists in the types and delivery, RCTs of MBIs have demonstrated small-to-moderate positive effects on HF patients' objective and subjective outcomes. Future research should examine the mechanisms by which different MBIs exert their effects.

Post-Heart Transplant Diastolic Dysfunction Is a Risk Factor for Mortality

OBJECTIVES

The purpose of this study was to evaluate the incidence and prognostic implication of diastolic dysfunction (DD) occurring in the first year after transplant.

BACKGROUND

Diastolic dysfunction is a recognized complication in heart transplant recipients, but its true incidence and natural history has been poorly characterized. We studied the prognostic implication of DD, as defined by elevated filling pressures with normal systolic function, occurring in the first year after transplant.

METHODS

Between June 1992 and June 2002, all patients who underwent heart transplantation at a single institution were included in the study (231 at 6 weeks and 250 at 6 months and 1 year). Diastolic dysfunction was defined as right atrial pressure (RAP) >/=15 mm Hg (right ventricular [RV] DD) or pulmonary capillary wedge pressure >/=18 mm Hg (left ventricular [LV] DD) with normal systolic function by echocardiogram and without severe mitral or tricuspid insufficiency. In addition, RV DD was defined by a RAP/stroke volume (SV) ratio.

RESULTS

The incidence of DD was 22%, 8%, and 12% at 6 weeks, 6 months, and 1 year, respectively. The incidence of LV DD was more frequent than that of RV DD at any time point (p < 0.0001). By multivariable analysis RV DD, as manifested by an elevated RAP/SV, but not LV DD was a strong predictor of cardiac mortality at all time points.

CONCLUSIONS

Diastolic dysfunction is common early after transplant, and its incidence decreases during the first year. Right ventricular DD, as measured by an elevated RAP/SV ratio, but not LV DD is a strong predictor of cardiac mortality. Further studies are needed to evaluate the functional status of patients with RV or LV DD and whether aggressive medical therapy for early DD could alter outcome.

Genetic Polymorphism in Platelet-derived Growth Factor and Vascular Endothelial Growth Factor Are Significantly Associated With Cardiac Allograft Vasculopathy

BACKGROUND

The role of cytokine gene polymorphism and its association with acute heart allograft rejection and cardiac allograft vasculopathy (CAV) is controversial. The role of growth factor gene polymorphism has never been investigated in heart allograft recipients.

METHODS

Seventy heart transplant recipients were studied. Mean age at transplant was 50.4 +/- 12.4 years (73% white, 91% male). Patients were followed for an average of 28 +/- 12 months. Cellular rejection episodes were determined based on criteria established by the International Society of Heart and Lung Transplantation. Angiography and intravascular ultrasound (IVUS) were performed annually. Cytokine and growth factor polymorphism data were analyzed using the single-nucleotide polymorphism polymerase chain reaction (SNP PCR) approach.

RESULTS

Patients who developed early CAV, documented by angiography, had increased frequency of the interferon-gamma high-producer phenotype, increased frequency of PDGF-286 AA, and decreased frequency of PDGF-1135 CC (p < 0.03, p < 0.03 and p = 0.01, respectively). Platelet-derived growth factor (PDGF) associations with early CAV were substantiated when vasculopathy was determined by IVUS. Additional associations were identified with vascular endothelial growth factor (VEGF) polymorphisms-1154 GG and -2578 AC (p < 0.03 and p = 0.01, respectively). Some of these associations translated to decreased patient survival, as indicated by Kaplan-Meier analysis. No significant association was identified between cytokine gene polymorphism (tumor necrosis factor-alpha, transforming growth factor-beta, interferon-gamma, interleukin-6 and interleukin-10) and acute cellular rejection episodes.

CONCLUSIONS

These data suggest an association between PDGF and VEGF polymorphism and CAV. It is essential, however, due to the redundancy of the immune system and other confounding factors, that future studies be centrally conducted and include multiple programs, large cohorts of patients and properly chosen controls. Only then will we be able to identify the true association between cytokine and growth factor polymorphism and heart transplant outcome.

Response of Doxorubicin-induced Cardiomyopathy to the Current Management Strategy of Heart Failure

BACKGROUND

Doxorubicin (D) (Adriamycin) is a potent and efficacious chemotherapeutic agent in the treatment of various forms of cancer, but its use has been limited by the development of cardiac toxicity. Historically, D-induced cardiomyopathy (CMP) has been refractory to therapy. We report our experience with this form of CMP at the University of Alabama at Birmingham.

METHODS

Twenty-five patients (20 women, 5 men) with a clinical diagnosis of D-CMP were referred to our program from 1990 to 2003. Patient data were extracted from office charts.

RESULTS

Patients were followed-up for 71 +/- 58 months. On presentation, the average left ventricular ejection fraction (LVEF) was 26 +/- 9.2%, and 88% of patients were New York Heart Association (NYHA) Class III or IV. Patients were treated with angiotensin-converting enzyme inhibitors (ACEi; n = 23) or angiotensin-receptor blocker (ARB; n = 2), and 15 were treated with a combination of ACEi and beta-blockers (BB). With medical therapy, LVEF improved significantly (26 +/- 9.2% vs 35 +/- 16.5%, p = 0.022), as did the NYHA class (p < 0.003). All survivors (n = 19) were NYHA Class I or II with medical therapy, with 10 (53%) being Class I. In the group of patients treated with ACEi + BB, there was a statistically significant improvement in LVEF (26 +/- 10.0% vs 37 +/- 17.6%, p = 0.028), which not seen in the ACEi group, with a strong trend toward normalization of LV function (47% vs 10%, p = 0.054).

CONCLUSIONS

In the current era of management of heart failure, D-CMP carries a better prognosis than previously described. Early addition of BB may further improve LVEF.