Christopher V. Chien

Ventricular Arrhythmias After Left Ventricular Assist Device

Despite advances in medical therapy, heart failure remains one of the major causes of hospitalizations and deaths in the United States. Approximately 5.7 million patients have heart failure, and it is the direct cause of death for 57 000 individuals annually.1 Although the combination of optimal medical therapy, implantable cardioverter-defibrillators (ICDs), and cardiac resynchronization therapy has reduced mortality rates, an estimated 50% of patients with heart failure still die within 5 years of diagnosis.1 Heart transplant is often the best therapeutic option for patients with end-stage heart failure; however, there has been a stable plateau of ≈2200 transplants/y in the United States due largely to limitations in organ availability.1 For patients who are facing unfavorably long wait times for heart transplantation, left ventricular assist devices (LVAD) have become a lifesaving option as a bridge to transplant. Currently, one quarter to one third of all heart transplant recipients are bridged with mechanical circulatory support before transplantation.2 Much of this support is in the form of permanent LVADs—surgically implanted mechanical assist devices that unload the left ventricle and can function in ambulatory patients (Figure 1). The use of permanent LVADs as destination therapy has increased dramatically, with evidence that they benefit patients with end-stage heart failure, despite noncandidacy for heart transplantation. Since the seminal Randomized Evaluation of Mechanical Assistance for the Treatment of Congestive Heart Failure destination therapy trial in 2001, ≈1578 destination therapy LVADs have been implanted, with implant rates increasing rapidly.3,4 Figure 1. Examples of implantable cardioverter-defibrillators (ICDs) with 2 different types of left ventricular assist devices (LVADs). Posterior-anterior chest x-ray projections of biventricular ICDs in the presence of HVAD ( A ) and Heartmate II ( B ) models of LVAD. Development of LVADs dates to 1969 when the world’s first total artificial heart was implanted by Dr …

Trajectories of heart failure self-care management and changes in quality of life

Introduction: Heart failure patients vary considerably in their self-care management behaviors (i.e. recognizing and responding to symptoms). The goal of this study was to identify unique patterns of change in heart failure self-care management and quantify associations between self-care management and quality of life (HRQOL) over time. Methods: A prospective cohort study among adults with symptomatic heart failure was designed to measure changes in self-care management (Self-care of Heart Failure Index) and HRQOL (Kansas City Cardiomyopathy Questionnaire) over six months. Growth mixture modeling was used to identify unique trajectories of change in self-care management. Results: The mean age (n=146) was 57 years, 70% were male, and 41% had class II heart failure. Two trajectories of self-care management were identified (entropy = 0.88). The larger trajectory (73.3%) was characterized by a significant decline in self-care management over time and no change in HRQOL. The smaller trajectory (26.7%) was characterized by marked improvements in self-care management and HRQOL. Changes in heart failure self-care management occurred in the absence of change in routine self-care maintenance behaviors, functional classification, and physical and psychological symptoms. Patients with greater physical symptoms at enrollment (odds ratio (OR) =1.04, p=0.037), larger left ventricles (OR=1.50, p=0.044), and ischemic heart failure (OR=3.84, p=0.014) were more likely to have the declining trajectory of self-care management. Higher levels of depression at enrollment were associated with reduced odds of having a decline in self-care management over time (OR=0.85, p<0.001). Conclusions: There are unique and clinically-relevant trajectories of change in heart failure self-care management that are associated with differences in HRQOL.

Profiles of self-care management versus consulting behaviors in adults with heart failure

Introduction: Patients with heart failure (HF) vary in their ability to respond to symptoms when they occur. The goal of this study was to classify common patterns of symptom response behaviors among adults with HF and identify biobehavioral determinants thereof. Methods: Consulting behaviors (i.e. contacting a provider for guidance) were measured using the European Heart Failure Self-care Behavior Scale consulting behaviors subscale, and self-care management (i.e. recognizing and engaging in self-initiated treatment of symptoms) was measured with the Self-Care of HF Index self-care management scale in a prospective cohort study. Latent class mixture modeling was used to identify distinct profiles of consulting and of self-care management behaviors. Results: The mean age (n=146) was 57±13 years, 30% were female, and 59% had class III/IV HF. Two distinct profiles of consulting behaviors (novice and expert) and three distinct profiles of self-care management (novice, inconsistent and expert) were identified. There was a weak association between profiles of consulting behaviors and self-care management (Kendall’s tau-b=0.211). Higher levels of anxiety were associated with worse consulting behaviors (β=1.67±0.60) and worse self-care management (β= −5.82±3.12) and lower odds of exhibiting expert level consulting behaviors (odds ratio (OR)=0.50; 95% confidence interval (CI)=0.26–0.95) and self-care management (OR=0.47; 95% CI=0.24–0.92) (all p<0.05). Higher levels of physical symptoms were associated with better self-care management (β=0.50±0.12; OR =1.02, 95% CI=1.00–1.05; both p<0.05). Conclusions: Expertise in consulting behaviors does not necessarily confer expertise in symptom self-care management and vice versa. Physical and psychological symptoms are strong determinants of symptom response behaviors.

Quality of Life, Depression, and Anxiety in Ventricular Assist Device Therapy: Longitudinal Outcomes for Patients and Family Caregivers

Background: Patients who receive ventricular assist device (VAD) therapy typically rely on informal caregivers (family members or friends) to assist them in managing their device. Objective: The purpose of this study is to characterize changes in person-oriented outcomes (quality of life [QOL], depression, and anxiety) for VAD patients and their caregivers together from pre-implantation to 3 months post-implantation. Methods: This was a formal interim analysis from an ongoing prospective study of VAD patients and caregivers (n = 41 dyads). Data on person-oriented outcomes (QOL: EuroQol 5 Dimensions Visual Analog Scale; depression: Patient Health Questionnaire-8; anxiety: Brief Symptom Inventory) were collected at 3 time points (just prior to implantation and at 1 and 3 months post-implantation). Trajectories of change for patients and caregivers on each measure were estimated using latent growth modeling with parallel processes. Results: Patients’ QOL improved significantly over time, whereas caregiver QOL worsened. Depression and anxiety also improved significantly among patients but did not change among caregivers. There was substantial variability in change on all outcomes for both patients and their caregivers. Conclusions: This is the first quantitative study of VAD patient-caregiver dyads in modern devices that describes change in person-oriented outcomes from pre-implantation to post-implantation. This work supports the need for future studies that account for the inherent relationships between patient and caregiver outcomes and examine variability in patient and caregiver responses to VAD therapy.

Patterns, relevance and predictors of heart failure dyadic symptom appraisal

Background: Caregivers are thought to play a major role in helping patients first appraise and then respond to heart failure (HF) symptoms. Aims: The aims of this study were to: (a) characterise distinct patterns of HF patient–caregiver dyads with respect to symptom appraisal; and (b) link dyadic symptom appraisal to contributions to self-care and caregiver strain. Methods and results: A cross-sectional dyadic descriptive design was used to capture patient and caregiver appraisal of patient HF symptoms (i.e. dyspnoea, fatigue, pain and anxiety). Contributions to self-care were measured using patient and caregiver versions of the Self-Care of Heart Failure Index and the European Heart Failure Self-care Behaviour Scale. Caregiver strain was measured using the Multidimensional Caregiver Strain Index. Multilevel and latent class mixture modelling (LCMM) were used to examine distinct patterns of symptom appraisal. Two patterns of dyadic symptom appraisal were identified: one pattern (n = 24; 38.7%) wherein caregivers appraised patients’ symptoms as being significantly worse than did the patient (labelled as ‘Caregiver > Patient’); and a second pattern (n = 38; 61.3%) wherein patients appraised their symptoms similar to or worse than that as perceived by their caregiver (labelled as ‘Patient ⩾ Caregiver’). Dyads in the Caregiver > Patient pattern of symptom appraisal reported much better contributions to self-care (symptom response behaviours only), but also greater caregiver strain, compared with dyads in the Patient ⩾ Caregiver pattern. Greater patient depression and older caregiver age were significant determinants of fitting the Patient ⩾ Caregiver pattern. Conclusion: Differences in how HF patients and caregivers appraise symptoms together must be taken into consideration when examining contributions to HF care and caregiver outcomes.

Symptom-hemodynamic mismatch and heart failure event risk

Background:Heart failure (HF) is a heterogeneous condition of both symptoms and hemodynamics. Objective:The goals of this study were to identify distinct profiles among integrated data on physical and psychological symptoms and hemodynamics and quantify differences in 180-day event risk among observed profiles. Methods:A secondary analysis of data collected during 2 prospective cohort studies by a single group of investigators was performed. Latent class mixture modeling was used to identify distinct symptom-hemodynamic profiles. Cox proportional hazards modeling was used to quantify difference in event risk (HF emergency visit, hospitalization, or death) among profiles. Results:The mean age (n = 291) was 57 ± 13 years, 38% were female, and 61% had class III/IV HF. Three distinct symptom-hemodynamic profiles were identified: 17.9% of patients had concordant symptoms and hemodynamics (ie, moderate physical and psychological symptoms matched the comparatively good hemodynamic profile), 17.9% had severe symptoms and average hemodynamics, and 64.2% had poor hemodynamics and mild symptoms. Compared with those in the concordant profile, both profiles of symptom-hemodynamic mismatch were associated with a markedly increased event risk (severe symptoms hazards ratio, 3.38; P = .033; poor hemodynamics hazards ratio, 3.48; P = .016). Conclusions:A minority of adults with HF have concordant symptoms and hemodynamics. Either profile of symptom-hemodynamic mismatch in HF is associated with a greater risk of healthcare utilization for HF or death.

Usefulness of Cognitive Dysfunction in Heart Failure to Predict Cardiovascular Risk at 180 days

Cognitive dysfunction is common in patients with heart failure (HF). Despite the high prevalence and the adverse associations of cognitive dysfunction in HF, the prognostic implications remain poorly understood. We sought to determine the influence of cognitive dysfunction, identified using the Montreal Cognitive Assessment (MoCA), on 180-day cardiovascular events. We analyzed data on 246 participants in an observational cohort study of adults with HF. The interview-format MoCA was administered to all participants. Time to first cardiovascular event was assessed as a cumulative end point during the 180 days after enrollment. Cox proportional hazards model was used for analysis of time to first event. The MoCA score was <26 for 91 patients (37%). Patients with a MoCA score <26 were more likely to have a cardiovascular event at 180 days. MoCA score <26 remained an independent predictor of cardiovascular event risk at 180 days when adjusted for the Seattle Heart Failure Model Score and the Charlson comorbidity index (hazard ratio 1.7, 95% confidence interval 1.1 to 2.6, p = 0.03). In conclusion, in patients with HF, cognitive dysfunction identified with a MoCA score of <26 is associated with increased risk of cardiovascular events at 180 days.

The Role of Dyadic Confidence on Engagement in Heart Failure Care Behaviors

Background and Objectives Increasingly, older adults and their families are expected to manage complex conditions with little support. In the case of heart failure (HF), symptom monitoring and management are critical in preventing acute exacerbations and poor clinical outcomes. The current study examined the role of dyadic confidence on engagement in HF care behaviors by patients and their spouses. Research Design and Methods A cross-sectional design was used to examine 60 couples living with HF. Three dyadic confidence variables were created to represent average level of confidence, gap in confidence, and direction of gap within each couple. A series of multilevel models were used to examine dyadic engagement in HF maintenance, management, and consulting behaviors and the role of dyadic confidence. Results Patients were significantly more engaged in HF maintenance behaviors than spouses; couples were more collaborative in their engagement in HF management and consulting behaviors. Average level of confidence in the dyad was significantly associated with patient engagement in all three HF behaviors. Spouse engagement was associated with more congruence in confidence and having higher levels of confidence than their partners with HF. Women were significantly more engaged in HF behaviors than men, regardless of role. Discussion and Implications The study employed a dyadic approach to HF care and a novel approach to confidence. Findings confirm the social nature of confidence and its important role in HF. Clinicians have opportunities to optimize patient outcomes by fostering greater collaboration within couples.

Physical and psychological symptom biomechanics in moderate to advanced heart failure.

Background:There is a common dissociation between objective measures and patient symptomatology in heart failure (HF). Objective:The aim of this study was to explore the relationship between cardiac biomechanics and physical and psychological symptoms in adults with moderate to advanced HF. Methods:We performed a secondary analysis of data from 2 studies of symptoms among adults with HF. Stepwise regression modeling was performed to examine the influence of cardiac biomechanics (left ventricular internal diastolic diameter, right atrial pressure [RAP], and cardiac index) on symptoms. Results:The average age of the sample (n = 273) was 57 ± 16 years, 61% were men, and 61% had class III or IV HF. Left ventricular internal diastolic diameter (&bgr; = 4.22 ± 1.63, P = .011), RAP (&bgr; = 0.71 ± 0.28, P = .013), and cardiac index (&bgr; = 7.11 ± 3.19, P = .028) were significantly associated with physical symptoms. Left ventricular internal diastolic diameter (&bgr; = 0.10 ± 0.05, P = .038) and RAP (&bgr; = 0.03 ± 0.01, P = .039) were significantly associated with anxiety. There were no significant biomechanical determinants of depression. Conclusion:Cardiac biomechanics were related to physical symptoms and anxiety, providing preliminary evidence of the biological underpinnings of symptomatology among adults with HF.

Patient and Caregiver Determinants of Patient Quality of Life and Caregiver Strain in Left Ventricular Assist Device Therapy

Background Although current guidelines emphasize the importance of social support to the success of left ventricular assist device (LVAD) therapy, few studies examine the influence of the caregiver on patient outcomes or quantify the impact of LVAD caregiving on caregiver outcomes. The purpose of this analysis was to identify patient and caregiver determinants of patient quality of life (QOL) and caregiver strain in response to LVAD therapy. Methods and Results Data on patients receiving LVAD therapy and their caregivers (n=50 dyads) were prospectively collected pre‐implantation and 1, 3, and 6 months post‐implantation. Growth curve modeling was used to describe change in patient QOL (Kansas City Cardiomyopathy Questionnaire) and caregiver strain (Multidimensional Caregiver Strain Index). Patient QOL improved most in the first month (β=23.22±3.76, P<0.001), followed by gradual gains over 6 months (β=1.90±0.64, P<0.01). Caregivers experienced worsening of strain in the first month (β=4.30±1.42, P<0.01), followed by gradual resolution to pre‐implantation levels by 6 months (β=−0.71±0.23, P<0.01). Worse pre‐implantation patient symptoms were associated with greater improvement in patient QOL (β=0.53±0.19, P<0.01) but worsening caregiver strain (β=0.15±0.07, P=0.04). Better relationship quality was associated with greater improvement in patient QOL (β=14.39±5.85, P=0.01) and less pre‐implantation caregiver strain (β=−9.31±2.28, P<0.001). Nonspousal caregivers experienced less pre‐implantation strain (β=−8.60±3.10, P=0.01), and patients with nonspousal caregivers had less improvement in QOL (β=−3.70±1.62, P=0.02). Conclusions A combination of patient and caregiver characteristics predicts patient and caregiver response to LVAD therapy. Including caregiver factors in future studies may be helpful in developing interventions that improve patient and caregiver outcomes, together.