Patient selection for advanced heart failure therapy referral. Crit Pathw Cardiol. 2014;13:1-5. [PMID: 24526143 DOI: 10.1097/hpc.0000000000000004]

Examining Risk Factors Related to Cardiac Rehabilitation Cessation Among Patients With Advanced Heart Failure

PURPOSE

Cardiac rehabilitation (CR) is beneficial in heart transplant and left ventricular assist device (LVAD) recipients, but patterns of attendance remain poorly understood. We describe CR adherence and cessation in this population.

METHODS

We performed a retrospective review of heart transplant and LVAD recipients who attended ≥1 CR session at a tertiary medical center (2013-2022). Complete adherence was defined as attending 36 sessions. Primary reasons for cessation before 36 sessions were recorded. We compared post-operative complications, duration of hospitalization, and readmissions between participants with and without complete adherence using logistic and linear regressions. Among participants with complete adherence, we compared changes in metabolic equivalent of task (MET), exercise time, and peak oxygen uptake using paired sample t tests.

RESULTS

There were 137 heart transplant and LVAD recipients (median age 56.9 years, 74% male) who attended CR. Among them, 91% either completed 36 CR sessions or <24 sessions. Among those without complete adherence (n = 74), 72% reported medical reasons, and 15% reported personal reasons for cessation. Compared to those who completed CR, those without complete adherence experienced more post-operative complications (44% vs 24%, P = .02) and major bleeding (23% vs 7%, P = .02) prior to CR. Participants with complete adherence experienced significant improvements in exercise time (142.5 seconds), MET (0.4), and peak oxygen uptake (1.4 mL/kg/min).

CONCLUSIONS

Nearly half of heart transplant and LVAD recipients in CR completed all 36 sessions. Those with complete adherence experienced significant improvements in exercise measures, underscoring the important benefits of CR in this population.

Knowledge and application of ESC/HFA guidelines in the management of advanced heart failure

AIMS

Management of advanced heart failure (HF) remains challenging despite specific sections in the 2021 European Society of Cardiology/Heart Failure Association (ESC/HFA) guidelines, with delays in referrals exacerbating the issue. This study aimed to evaluate the awareness and implementation of these guidelines among cardiologists and identify barriers to effective referral.

METHODS AND RESULTS

From June to October 2023, an online survey was disseminated through the ESC mailing list, targeting cardiologists across Europe. The survey investigated four areas: guideline awareness, healthcare network organization, clinical case management, and perceptions of mechanical circulatory support (MCS) outcomes. Respondents were categorized into heart failure cardiologists (HFCs), general cardiologists (GCs), and other participants (OPs). Among 497 respondents, 25% were heart HFCs, 40% were GCs, and 35% were OPs. A total of 84% of HFCs reported a high level of guideline knowledge, compared to 57% of GCs and 62% of OPs (p < 0.001). Additionally, 76% of HFCs 'regularly or always' used ESC/HFA criteria to identify advanced HF, compared to 44% of GCs and 48% of OPs (p < 0.001). Correct responses regarding the recommendation class for heart transplantation were 84%, 55%, and 60% (p < 0.0001), and for MCS as a bridge to transplantation, 69%, 65%, and 55% (p = 0.018) among HFCs, GCs, and OPs, respectively. Referring patients with severe HF to a tertiary centre team was found to be 'very difficult' or 'difficult' by 8.4% of HFCs, 19.6% of GCs, and 18.2% of OPs (p = 0.0005).

CONCLUSION

The study highlights significant disparities in knowledge and application of advanced HF guidelines among cardiologists, revealing an opportunity for educational initiatives. The difficulty in referring patients to tertiary centres underscores the need to improve the referral pathway for advanced HF patients.

Predicting need for heart failure advanced therapies using an interpretable tropical geometry-based fuzzy neural network

BACKGROUND

Timely referral for advanced therapies (i.e., heart transplantation, left ventricular assist device) is critical for ensuring optimal outcomes for heart failure patients. Using electronic health records, our goal was to use data from a single hospitalization to develop an interpretable clinical decision-making system for predicting the need for advanced therapies at the subsequent hospitalization.

METHODS

Michigan Medicine heart failure patients from 2013-2021 with a left ventricular ejection fraction ≤ 35% and at least two heart failure hospitalizations within one year were used to train an interpretable machine learning model constructed using fuzzy logic and tropical geometry. Clinical knowledge was used to initialize the model. The performance and robustness of the model were evaluated with the mean and standard deviation of the area under the receiver operating curve (AUC), the area under the precision-recall curve (AUPRC), and the F1 score of the ensemble. We inferred membership functions from the model for continuous clinical variables, extracted decision rules, and then evaluated their relative importance.

RESULTS

The model was trained and validated using data from 557 heart failure hospitalizations from 300 patients, of whom 193 received advanced therapies. The mean (standard deviation) of AUC, AUPRC, and F1 scores of the proposed model initialized with clinical knowledge was 0.747 (0.080), 0.642 (0.080), and 0.569 (0.067), respectively, showing superior predictive performance or increased interpretability over other machine learning methods. The model learned critical risk factors predicting the need for advanced therapies in the subsequent hospitalization. Furthermore, our model displayed transparent rule sets composed of these critical concepts to justify the prediction.

CONCLUSION

These results demonstrate the ability to successfully predict the need for advanced heart failure therapies by generating transparent and accessible clinical rules although further research is needed to prospectively validate the risk factors identified by the model.

Efficacy and safety of digital therapeutics-based cardiac rehabilitation in heart failure patients: a systematic review

During the coronavirus disease 2019 (COVID-19) pandemic, it has become difficult to provide centre-based cardiac rehabilitation for heart failure patients. Digital therapeutics is a novel concept proposed in recent years that refers to the use of evidence-based therapeutic interventions driven by high-quality software programs to treat, manage, or prevent a medical condition. However, little is known about the use of this technology in heart failure patients. This study aims to explore the safety and efficacy of digital therapeutics-based cardiac rehabilitation in heart failure patients and to provide new insights into a new cardiac rehabilitation model during the COVID-19 era. To identify technologies related to digital therapeutics, such as the use of medical applications, wearable devices, and the Internet, all relevant studies published on PubMed, EMBASE, Cochrane database, and China National Knowledge Internet were searched from the time the database was established until October 2021. The PEDro was used to assess the quality of included studies. We ultimately identified five studies, which included 1119 patients. The mean age was 66.37, the mean BMI was 25.9, and the NYHA classification ranged from I to III (I = 232, II = 157, III = 209). The mean 6-min walk distance was 397.7 m. The PEDro scores included in the study ranged from 4 to 8, with a mean of 5.8. Exercise training was performed in four studies, and psychological interventions were conducted in three studies. No death or serious adverse events were observed. Adherence was reported in three studies, and all exceeded 85%. The results of most studies showed that digital therapeutics-based cardiac rehabilitation significantly increases exercise capacity and quality of life in heart failure patients. Overall, although this study suggests that digital therapeutics-based cardiac rehabilitation may be a viable intervention for heart failure patients during the COVID-19 era, the efficacy of this new model in routine clinical practice needs to be further validated in a large clinical trial.

Determining the factors for interhospital transfer in advanced heart failure cases

Background

There are some patients with advanced heart failure (HF), for whom implantable left ventricular assist device (LVAD) or heart transplantation (HTx) should be considered. Some of them need to be transferred between hospitals. There are few reports on the interhospital transfer of patients with advanced HF and their subsequent clinical course.

In this study, we investigated the characteristics and clinical course of patients transferred to a LVAD/HTx center, focusing on the distance between hospitals.

Methods

We retrospectively examined 141 patients who were transferred to our hospital, considering the indications of LVAD implantation or HTx. We divided the patients into two groups: those referred <33 km (short-distance) and those referred more than 33 km (long-distance). The primary outcome was the composite outcome of increased catecholamine dose, mechanical support, or renal dysfunction within 1 week of transfer.

Results

Continuous catecholamine infusion was significantly more common in patients in the long-distance group, whereas extracorporeal membrane oxygenation (ECMO) placement was significantly more common in short-distance group.

Patients transferred via long distance had significantly higher rates of increased catecholamine doses, mechanical support including intra-aortic balloon pumping (IABP) and ECMO, and renal dysfunction within 1 week of transfer than patients transferred via short distance. Multivariate analysis showed that low body mass index (BMI) and long distance were independent predictive factors for the primary outcome.

Conclusions

When patients with advanced HF are transferred from far distant hospitals or with low BMI, it may be necessary to devise various measures for interhospital transport.

Frailty Assessment in Heart Failure and Ventricular Assist Device Populations: A Review from the United States

IMPORTANCE

Post-operative risk is increased with frail individuals undergoing cardiac surgery. Yet, there is no consensus for frailty assessment prior to durable left ventricular assist device (dLVAD) evaluation.

OBJECTIVE

The objectives of this integrative review were to describe frailty measures, examine psychometrics of measures used, and identify variables related to frailty in heart failure with reduced ejection fraction (HFrEF) and dLVAD populations.

DESIGN, SETTING, PARTICIPANTS

PubMed, CINAHL, and Embase databases were searched for terms related to frailty, HFrEF and dLVAD that met inclusion criteria.

RESULTS

Fourteen articles met inclusion criteria. Frailty was inconsistently defined. The Fried Phenotype Criteria was the most widely used approach to measurement. Validity was reported in all articles. Variables related to frailty included readmissions, higher mortality and increased adverse events.

CONCLUSION

There was variability in frailty definition and frailty measurement across studies. Further research in HFrEF and dLVAD populations is needed for frailty evaluation.

Discordance Between Severity of Heart Failure as Determined by Patient Report Versus Cardiopulmonary Exercise Testing

Background

Patient‐reported outcomes may be discordant to severity of illness as assessed by objective parameters. The frequency of this discordance and its influence on clinical outcomes in patients with heart failure is unknown.

Methods and Results

In HF‐ACTION (Heart Failure: A Controlled Trial Investigating Outcomes of Exercise Training), participants (N=2062) had baseline assessment of health‐related quality of life via the Kansas City Cardiomyopathy Clinical Summary score (KCCQ‐CS) and objective severity by cardiopulmonary stress testing (minute ventilation [V_E]/carbon dioxide production [VCO₂] slope). We defined 4 groups by median values: 2 concordant (lower severity: high KCCQ‐CS and low V_E/VCO₂ slope; higher severity: low KCCQ‐CS and high V_E/VCO₂ slope) and 2 discordant (symptom minimizer: high KCCQ‐CS and high V_E/VCO₂ slope; symptom magnifier: low KCCQ‐CS and low V_E/VCO₂ slope). The association of group assignment with mortality was assessed in adjusted Cox models. Symptom magnification (23%) and symptom minimization (23%) were common. Despite comparable KCCQ‐CS scores, the risk of all‐cause mortality in symptom minimizers versus concordant–lower severity participants was increased significantly (hazard ratio [HR], 1.79; 95% CI, 1.27–2.50; P<0.001). Furthermore, despite symptom magnifiers having a KCCQ‐CS score 28 points lower (poorer QOL) than symptom minimizers, their risk of mortality was not increased (HR, 0.79; 95% CI, 0.57–1.1; P=0.18, respectively).

Conclusions

Severity of illness by patient report versus cardiopulmonary exercise testing was frequently discordant. Mortality tracked more closely with the objective data, highlighting the importance of relying not only on patient report, but also objective data when risk stratifying patients with heart failure.

Practices of Referring Patients to Advanced Heart Failure Centers

BACKGROUND

Therapies for advanced heart failure (AHF) improve the likelihood of survival in a growing population of patients with stage D heart failure (HF). Successful implementation of these therapies is dependent upon timely and appropriate referrals to AHF centers.

METHODS

We performed a retrospective analysis of patients referred to 9 AHF centers for evaluation for AHF therapies. Patients' demographics, referring providers' characteristics, referral circumstances, and evaluation outcomes were collected.

RESULTS

The majority of referrals (n = 515) were male (73.4%), and a majority of those were in the advanced state of the disease: very low left ventricular ejection fraction (<20% in 51.5%); 59.4% inpatient; and high risk Interagency Registry for Mechanically Assisted Circulatory Support (INTERMACS) profiles (74.5% profile 1-3). HF cardiologists (49.1%) were the most common originating referral source; the least common (4.9%) were electrophysiologists. Common clinical triggers for referral included worsening HF (30.0%), inotrope dependence (19.6%), hospitalization (19.4%), and cardiogenic shock (17.8%). Most commonly, AHF therapies were not offered because patients were too sick (38.0%-45.1%) or for psychosocial reasons (20.3%-28.6%). Compared to non-HF cardiologists, patients referred by HF cardiologists were offered an AHF therapy more often (66.8% vs 58.4%, P = 0.0489). Of those not offered any AHF therapy, 28.4% received home inotropic therapy, and 14.5% were referred to hospice.

CONCLUSIONS

In this multicenter review of AHF referrals, HF cardiologists referred the most patients despite being a relatively small proportion of the overall clinician population. Late referral was prevalent in this high-risk patient population and correlates with worsened outcomes, suggesting a significant need for broad clinician education regarding the benefits, triggers and appropriate timing of referral to AHF centers for optimal patient outcomes.

Systematizing Heart Failure Population Health

Population health and population health management of patients with heart failure aim to identify all patients with the condition in a population, to characterize and risk stratify subgroups of patients, to improve care delivery by leveraging technology and data so providers can improve care coordination, to engage disease management programs, and to create cost-effective health systems that reduce financial burden on patients and providers. This requires a shift in our treatment paradigm from reactive treatment to proactive primary and secondary prevention. Shifts from fee-for-service to value-based payment models promise to encourage population health.

Focusing on Referral Rather than Selection for Advanced Heart Failure Therapies

Despite advances in heart failure treatment, advanced heart failure affects 5–10% of people with the condition and is associated with poor prognosis. Selection for heart transplantation and left ventricular assist device implantation is a rigorous and validated process performed by specialised heart failure teams. This entails comprehensive assessment of complex diagnostic tests and risk scores, and selecting patients with the optimal benefit-risk profile. In contrast, referral for advanced heart failure evaluation is an arbitrary and poorly studied process, performed by generalists, and patients are often referred too late or not at all. The study elaborates on the differences between selection and referral and proposes some simple strategies for optimising timely referral for advanced heart failure evaluation.

Optimal timing of same-admission orthotopic heart transplantation after left ventricular assist device implantation

AIM

To investigate the impact of timing of same-admission orthotopic heart transplant (OHT) after left ventricular assist device (LVAD) implantation on in-hospital mortality and post-transplant length of stay.

METHODS

Using data from the Nationwide Inpatient Sample from 1998 to 2011, we identified patients 18 years of age or older who underwent implantation of a LVAD and for whom the procedure date was available. We calculated in-hospital mortality for those patients who underwent OHT during the same admission as a function of time from LVAD to OHT, adjusting for age, sex, race, household income, and number of comorbid diagnoses. Finally, we analyzed the effect of time to OHT after LVAD implantation on the length of hospital stay post-transplant.

RESULTS

Two thousand and two hundred patients underwent implantation of a LVAD in this cohort. One hundred and sixty-four (7.5%) patients also underwent OHT during the same admission, which occurred on average 32 d (IQR 7.75-66 d) after LVAD implantation. Of patients who underwent OHT, patients who underwent transplantation within 7 d of LVAD implantation (“early”) experienced increased in-hospital mortality (26.8% vs 12.2%, P = 0.0483) compared to patients who underwent transplant after 8 d (“late”). There was no statistically significant difference in age, sex, race, household income, or number of comorbid diagnoses between the early and late groups. Post-transplant length of stay after LVAD implantation was also not significantly different between patients who underwent early vs late OHT.

CONCLUSION

In this cohort of patients who received LVADs, the rate of in-hospital mortality after OHT was lower for patients who underwent late OHT (at least 8 d after LVAD implantation) compared to patients who underwent early OHT. Delayed timing of OHT after LVAD implantation did not correlate with longer hospital stays post-transplant.