Is there a clinically meaningful difference in patient reported dyspnea in acute heart failure? An analysis from URGENT Dyspnea

Continuous infusion versus bolus injection of loop diuretics for acute heart failure

BACKGROUND

Acute heart failure (AHF) is new onset of, or a sudden worsening of, chronic heart failure characterised by congestion in about 95% of cases or end-organ hypoperfusion in 5% of cases. Treatment often requires urgent escalation of diuretic therapy, mainly through hospitalisation. This Cochrane review evaluated the efficacy of intravenous loop diuretics strategies in treating AHF in individuals with New York Heart Association (NYHA) classification III or IV and fluid overload.

OBJECTIVES

To assess the effects of intravenous continuous infusion versus bolus injection of loop diuretics for the initial treatment of acute heart failure in adults.

SEARCH METHODS

We identified trials through systematic searches of bibliographic databases and in clinical trials registers including CENTRAL, MEDLINE, Embase, CPCI-S on the Web of Science, ClinicalTrials.gov, the World Health Organization (WHO) International Clinical Trials Registry platform (ICTRP), and the European Union Trials register. We conducted reference checking and citation searching, and contacted study authors to identify additional studies. The latest search was performed on 29 February 2024.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) involving adults with AHF, NYHA classification III or IV, regardless of aetiology or ejection fraction, where trials compared intravenous continuous infusion of loop diuretics with intermittent bolus injection in AHF. We excluded trials with chronic stable heart failure, cardiogenic shock, renal artery stenosis, or end-stage renal disease. Additionally, we excluded studies combining loop diuretics with hypertonic saline, inotropes, vasoactive medications, or renal replacement therapy and trials where diuretic dosing was protocol-driven to achieve a target urine output, due to confounding factors.

DATA COLLECTION AND ANALYSIS

Two review authors independently screened papers for inclusion and reviewed full-texts. Outcomes included weight loss, all-cause mortality, length of hospital stay, readmission following discharge, and occurrence of acute kidney injury. We performed risk of bias assessment and meta-analysis where data permitted and assessed certainty of the evidence.

MAIN RESULTS

The review included seven RCTs, spanning 32 hospitals in seven countries in North America, Europe, and Asia. Data collection ranged from eight months to six years. Following exclusion of participants in subgroups with confounding treatments and different clinical settings, 681 participants were eligible for review. These additional study characteristics, coupled with our strict inclusion and exclusion criteria, improve the applicability of the body of the evidence as they reflect real-world clinical practice. Meta-analysis was feasible for net weight loss, all-cause mortality, length of hospital stay, readmission, and acute kidney injury. Literature review and narrative analysis explored daily fluid balance; cardiovascular mortality; B-type natriuretic peptide (BNP) change; N-terminal-proBNP change; and adverse incidents such as ototoxicity, hypotension, and electrolyte imbalances. Risk of bias assessment revealed two studies with low overall risk, four with some concerns, and one with high risk. All sensitivity analyses excluded trials at high risk of bias. Only narrative analysis was conducted for 'daily fluid balance' due to diverse data presentation methods across two studies (169 participants, the evidence was very uncertain about the effect). Results of narrative analysis varied. For instance, one study reported higher daily fluid balance within the first 24 hours in the continuous infusion group compared to the bolus injection group, whereas there was no difference in fluid balance beyond this time point. Continuous intravenous infusion of loop diuretics may result in mean net weight loss of 0.86 kg more than bolus injection of loop diuretics, but the evidence is very uncertain (mean difference (MD) 0.86 kg, 95% confidence interval (CI) 0.44 to 1.28; 5 trials, 497 participants; P < 0.001, I2 = 21%; very low-certainty evidence). Importantly, sensitivity analysis excluding trials with high risk of bias showed there was insufficient evidence for a difference in bodyweight loss between groups (MD 0.70 kg, 95% CI -0.06 to 1.46; 3 trials, 378 participants; P = 0.07, I2 = 0%). There may be little to no difference in all-cause mortality between continuous infusion and bolus injection (risk ratio (RR) 1.53, 95% CI 0.81 to 2.90; 5 trials, 530 participants; P = 0.19, I2 = 4%; low-certainty evidence). Despite sensitivity analysis, the direction of the evidence remained unchanged. No trials measured cardiovascular mortality. There may be little to no difference in the length of hospital stay between continuous infusion and bolus injection of loop diuretics, but the evidence is very uncertain (MD -1.10 days, 95% CI -4.84 to 2.64; 4 trials, 211 participants; P = 0.57, I2 = 88%; very low-certainty evidence). Sensitivity analysis improved heterogeneity; however, the direction of the evidence remained unchanged. There may be little to no difference in the readmission to hospital between continuous infusion and bolus injection of loop diuretics (RR 0.85, 95% CI 0.63 to 1.16; 3 trials, 400 participants; P = 0.31, I2 = 0%; low-certainty evidence). Sensitivity analysis continued to show insufficient evidence for a difference in the readmission to hospital between groups. There may be little to no difference in the occurrence of acute kidney injury as an adverse event between continuous infusion and bolus injection of intravenous loop diuretics (RR 1.02, 95% CI 0.70 to 1.49; 3 trials, 491 participants; P = 0.92, I2 = 0%; low-certainty evidence). Sensitivity analysis continued to show that continuous infusion may make little to no difference on the occurrence of acute kidney injury as an adverse events compared to the bolus injection of intravenous loop diuretics.

AUTHORS' CONCLUSIONS

Analysis of available data comparing two delivery methods of diuretics in acute heart failure found that the current data are insufficient to show superiority of one strategy intervention over the other. Our findings were based on trials meeting stringent inclusion and exclusion criteria to ensure validity. Despite previous reviews suggesting advantages of continuous infusion over bolus injections, our review found insufficient evidence to support or refute this. However, our review, which excluded trials with clinical confounders and RCTs with high risk of bias, offers the most robust conclusion to date.

Randomized controlled trial of urinE chemiStry guided aCute heArt faiLure treATmEnt (ESCALATE): Rationale and design

Diuresis to achieve decongestion is a central aim of therapy in patients hospitalized for acute decompensated heart failure (ADHF). While multiple clinical trials have investigated initial diuretic strategies for a designated period of time, there is a paucity of evidence to guide diuretic titration strategies continued until decongestion is achieved. The use of urine chemistries (urine sodium and creatinine) in a natriuretic response prediction equation accurately estimates natriuresis in response to diuretic dosing, but a randomized clinical trial is needed to compare a urine chemistry-guided diuresis strategy with a strategy of usual care. The urinE chemiStry guided aCute heArt faiLure treATmEnt (ESCALATE) trial is designed to test the hypothesis that protocolized diuretic therapy guided by spot urine chemistry through completion of intravenous diuresis will be superior to usual care and improve outcomes over the 14 days following randomization. ESCALATE will randomize and obtain complete data on 450 patients with acute heart failure to a diuretic strategy guided by urine chemistry or a usual care strategy. Key inclusion criteria include an objective measure of hypervolemia with at least 10 pounds of estimated excess volume, and key exclusion criteria include significant valvular stenosis, hypotension, and a chronic need for dialysis. Our primary outcome is days of benefit over the 14 days after randomization. Days of benefit combines patient symptoms captured by global clinical status with clinical state quantifying the need for hospitalization and intravenous diuresis. CLINICAL TRIAL REGISTRATION: NCT04481919.

Impact of serial cardiopulmonary point-of-care ultrasound exams in patients with acute dyspnoea: a randomised, controlled trial

BACKGROUND

Serial point-of-care ultrasound (PoCUS) can potentially improve acute patient care through treatment adjusted to the dynamic ultrasound findings. The objective was to investigate if treatment guided by monitoring patients with acute dyspnoea with serial cardiopulmonary PoCUS and usual care could reduce the severity of dyspnoea compared with usual care alone.

METHODS

This was a randomised, controlled, blinded-outcome trial conducted in three EDs in Denmark between 9 October 2019 and 26 May 2021. Patients aged ≥18 years admitted with a primary complaint of dyspnoea were allocated 1:1 with block randomisation to usual care, which included a single cardiopulmonary PoCUS within 1 hour of arrival (control group) or usual care (including a PoCUS within 1 hour of arrival) plus two additional PoCUS performed at 2 hours interval from the initial PoCUS (serial ultrasound group). The primary outcome was a reduction of dyspnoea measured on a verbal dyspnoea scale (VDS) from 0 to 10 recorded at inclusion and after 2, 4 and 5 hours.

RESULTS

There were 206 patients recruited, 102 in the serial ultrasound group and 104 in the control group, all of whom had complete follow-up. The mean difference in VDS between patients in the serial ultrasound and the control group was -1.09 (95% CI -1.51 to -0.66) and -1.66 (95% CI -2.09 to -1.23) after 4 and 5 hours, respectively. The effect was more pronounced in patients with a presumptive diagnosis of acute heart failure (AHF). A larger proportion of patients received diuretics in the serial ultrasound group.

CONCLUSION

Therapy guided by serial cardiopulmonary PoCUS may, together with usual care, facilitate greater improvement in the severity of dyspnoea, especially in patients with AHF compared with usual care with a single PoCUS in the ED. Serial PoCUS should therefore be considered for routine use to aid the physician in stabilising the patient faster.

TRIAL REGISTRATION NUMBER

NCT04091334.

Factors related to early readmissions after acute heart failure: a nested case-control study

AIMS

To describe the main characteristics of patients who were readmitted to hospital within 1 month after an index episode for acute decompensated heart failure (ADHF).

METHODS AND RESULTS

This is a nested case-control study in the ReIC cohort, cases being consecutive patients readmitted after hospitalization for an episode of ADHF and matched controls selected from those who were not readmitted. We collected clinical data and also patient-reported outcome measures, including dyspnea, Minnesota Living with Heart Failure Questionnaire (MLHFQ), Tilburg Frailty Indicator (TFI) and Hospital Anxiety and Depression Scale scores, as well as symptoms during a transition period of 1 month after discharge. We created a multivariable conditional logistic regression model. Despite cases consulted more than controls, there were no statistically significant differences in changes in treatment during this first month. Patients with chronic decompensated heart failure were 2.25 [1.25, 4.05] more likely to be readmitted than de novo patients. Previous diagnosis of arrhythmia and time since diagnosis ≥ 3 years, worsening in dyspnea, and changes in MLWHF and TFI scores were significant in the final model.

CONCLUSION

We present a model with explanatory variables for readmission in the short term for ADHF. Our study shows that in addition to variables classically related to readmission, there are others related to the presence of residual congestion, quality of life and frailty that are determining factors for readmission for heart failure in the first month after discharge.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT03300791. First registration: 03/10/2017.

Estimating Respiratory Rate From Breath Audio Obtained Through Wearable Microphones

Respiratory rate (RR) is a clinical metric used to assess overall health and physical fitness. An individual's RR can change from their baseline due to chronic illness symptoms (e.g., asthma, congestive heart failure), acute illness (e.g., breathlessness due to infection), and over the course of the day due to physical exhaustion during heightened exertion. Remote estimation of RR can offer a cost-effective method to track disease progression and cardio-respiratory fitness over time. This work investigates a model-driven approach to estimate RR from short audio segments obtained after physical exertion in healthy adults. Data was collected from 21 individuals using microphone-enabled, near-field headphones before, during, and after strenuous exercise. RR was manually annotated by counting perceived inhalations and exhalations. A multi-task Long-Short Term Memory (LSTM) network with convolutional layers was implemented to process mel-filterbank energies, estimate RR in varying background noise conditions, and predict heavy breathing, indicated by an RR of more than 25 breaths per minute. The multi-task model performs both classification and regression tasks and leverages a mixture of loss functions. It was observed that RR can be estimated with a concordance correlation coefficient (CCC) of 0.76 and a mean squared error (MSE) of 0.2, demonstrating that audio can be a viable signal for approximating RR.Clinical relevance-The subject technology facilitates the use of accessible, aesthetically acceptable wearable headphones to provide a technologically efficient and cost-effective method to estimate respiratory rate and track cardio-respiratory fitness over time.

Dyspnea Measurement in Acute Heart Failure: A Systematic Review and Evidence Map of Randomized Controlled Trials

Background: Dyspnea is the most common presenting symptom among patients hospitalized for acute heart failure (AHF). Dyspnea relief constitutes a clinically relevant therapeutic target and endpoint for clinical trials and regulatory approval. However, there have been no widely accepted dyspnea measurement standards in AHF. By systematic review and mapping the current evidence of the applied scales, timing, and results of measurement, we hope to provide some new insights and recommendations for dyspnea measurement. Methods: PubMed, Embase, Cochrane Library, and Web of Science were searched from inception until August 27, 2020. Randomized controlled trials (RCTs) with dyspnea severity measured as the endpoint in patients with AHF were included. Results: Out of a total of 63 studies, 28 had dyspnea as the primary endpoint. The Likert scale (34, 54%) and visual analog scale (VAS) (22, 35%) were most widely used for dyspnea assessment. Among the 43 studies with detailed results, dyspnea was assessed most frequently on days 1, 2, 3, and 6 h after randomization or drug administration. Compared with control groups, better dyspnea relief was observed in the experimental groups in 21 studies. Only four studies that assessed tolvaptan compared with control on the proportion of dyspnea improvement met the criteria for meta-analyses, which did not indicate beneficial effect of dyspnea improvement on day 1 (RR: 1.16; 95% CI: 0.99-1.37; p = 0.07; I ² = 61%). Conclusion: The applied scales, analytical approaches, and timing of measurement are in diversity, which has impeded the comprehensive evaluation of clinical efficacy of potential therapies managing dyspnea in patients with AHF. Developing a more general measurement tool established on the unified unidimensional scales, standardized operation protocol to record the continuation, and clinically significant difference of dyspnea variation may be a promising approach. In addition, to evaluate the effect of experimental therapies on dyspnea more precisely, the screening time and blinded assessment are factors that need to be considered.

Surface respiratory electromyography and dyspnea in acute heart failure patients

Introduction and Objectives: Dyspnea is the most common symptom among hospitalized patients with heart failure (HF) but besides dyspnea questionnaires (which reflect the subjective patient sensation and are not fully validated in HF) there are no measurable physiological variables providing objective assessment of dyspnea in a setting of acute HF patients. Studies performed in respiratory patients suggest that the measurement of electromyographic (EMG) activity of the respiratory muscles with surface electrodes correlates well with dyspnea. Our aim was to test the hypothesis that respiratory muscles EMG activity is a potential marker of dyspnea severity in acute HF patients. Methods: Prospective and descriptive pilot study carried out in 25 adult patients admitted for acute HF. Measurements were carried out with a cardio-respiratory portable polygraph including EMG surface electrodes for measuring the activity of main (diaphragm) and accessory (scalene and pectoralis minor) respiratory muscles. Dyspnea sensation was assessed by means of the Likert 5 questionnaire. Data were recorded during 3 min of spontaneous breathing and after breathing at maximum effort for several cycles for normalizing data. An index to quantify the activity of each respiratory muscle was computed. This assessment was carried out within the first 24 h of admission, and at day 2 and 5. Results: Dyspnea score decreased along the three measured days. Diaphragm and scalene EMG index showed a positive and significant direct relationship with dyspnea score (p<0.001 and p = 0.003 respectively) whereas pectoralis minor muscle did not. Conclusion: In our pilot study, diaphragm and scalene EMG activity was associated with increasing severity of dyspnea. Surface respiratory EMG could be a useful objective tool to improve assessment of dyspnea in acute HF patients.

Study protocol of coaching end-of-life palliative care for advanced heart failure patients and their family caregivers in rural appalachia: a randomized controlled trial

BACKGROUND

Heart failure (HF) afflicts 6.5 million Americans with devastating consequences to patients and their family caregivers. Families are rarely prepared for worsening HF and are not informed about end-of-life and palliative care (EOLPC) conservative comfort options especially during the end stage. West Virginia (WV) has the highest rate of HF deaths in the U.S. where 14% of the population over 65 years have HF. Thus, there is a need to investigate a new family EOLPC intervention (FamPALcare), where nurses coach family-managed advanced HF care at home.

METHODS

This study uses a randomized controlled trial (RCT) design stratified by gender to determine any differences in the FamPALcare HF patients and their family caregiver outcomes versus standard care group outcomes (N = 72). Aim 1 is to test the FamPALcare nursing care intervention with patients and family members managing home supportive EOLPC for advanced HF. Aim 2 is to assess implementation of the FamPALcare intervention and research procedures for subsequent clinical trials. Intervention group will receive routine standard care, plus 5-weekly FamPALcare intervention delivered by community-based nurses. The intervention sessions involve coaching patients and family caregivers in advanced HF home care and supporting EOLPC discussions based on patients' preferences. Data are collected at baseline, 3, and 6 months. Recruitment is from sites affiliated with a large regional hospital in WV and community centers across the state.

DISCUSSION

The outcomes of this clinical trial will result in new knowledge on coaching techniques for EOLPC and approaches to palliative and end-of-life rural home care. The HF population in WV will benefit from a reduction in suffering from the most common advanced HF symptoms, selecting their preferred EOLPC care options, determining their advance directives, and increasing skills and resources for advanced HF home care. The study will provide a long-term collaboration with rural community leaders, and collection of data on the implementation and research procedures for a subsequent large multi-site clinical trial of the FamPALcare intervention. Multidisciplinary students have opportunity to engage in the research process.

TRIAL REGISTRATION

ClinicalTrials.gov NCT04153890, Registered on 4 November 2019.

Mandibular advancement reveals long-term suppression of breathing discomfort in patients with obstructive sleep apnea syndrome

Obstructive sleep apnoea syndrome (OSAS) patients do not report breathing discomfort in spite of abnormal upper airway mechanics. We studied respiratory sensations in OSAS patients without and with mandibular advancement device (MAD). Fifty-seven moderate to severe non obese OSAS patients were asked about breathing discomfort using visual analogue scales (VAS) in the sitting position (VAS-1), after lying down (VAS-2), then with MAD (VAS-3). Awake critical closing pressure (awake Pcrit) was measured in 15 patients without then with MAD. None of the patients reported breathing discomfort when sitting but 19 patients (33%) did when lying (VAS-2: -20% or less). A feeling of "easier breathing" with MAD was observed and was more marked in patients reporting breathing discomfort when supine (VAS-3: +66.0% [49.0; 89.0]) than in those not doing so (VAS-3: +28.5% [1.0; 56.5], p = 0.007). MAD-induced change in awake Pcrit was correlated to VAS-3. In conclusion, MAD revealed "latent dyspnea" related to the severity of upper airways mechanics abnormalities in OSAS patients.

Effects of Oral Morphine on Dyspnea in Patients with Cancer: Response Rate, Predictive Factors, and Clinically Meaningful Change (CJLSG1101)

BACKGROUND

Although the efficacy of parenteral morphine for alleviating dyspnea has been previously demonstrated in several studies, little is known regarding the efficacy of oral morphine for dyspnea among patients with cancer, including its response rate and predictive factors of effectiveness. Therefore, the aim of this study was to clarify the effectiveness of oral morphine on dyspnea in patients with cancer and elucidate the predictive factors of its effectiveness.

SUBJECTS, MATERIALS, AND METHODS

In this multicenter prospective observational study, we investigated the change in dyspnea intensity in patients with cancer before and after the administration of oral morphine by using a visual analog scale (VAS). We also administered a self-assessment questionnaire to determine whether the patients believed oral morphine was effective.

RESULTS

Eighty patients were enrolled in the study, and 71 of these patients were eligible. The least square mean of the VAS scores for dyspnea intensity was 53.5 at baseline, which decreased significantly to 44.7, 40.8, and 35.0 at 30, 60, and 120 minutes after morphine administration, respectively. Fifty-four patients (76.1%) reported that oral morphine was effective on the self-assessment questionnaire. Among the background factors, a high score for "sense of discomfort" on the Cancer Dyspnea Scale (CDS) and a smoking history of fewer pack-years were associated with greater effectiveness.

CONCLUSION

Oral morphine was effective and feasible for treating cancer-related dyspnea. A higher score for "sense of discomfort" on the CDS and a smaller cumulative amount of smoking may be predictive factors of the effectiveness of oral morphine.

IMPLICATIONS FOR PRACTICE

This study demonstrated that oral morphine was effective in alleviating cancer-related dyspnea due to multiple factors including primary lung lesions, airway narrowing, and pleural effusion. Approximately 76% of patients reported that oral morphine was effective. A higher score for "sense of discomfort" on the Cancer Dyspnea Scale and a lower cumulative amount of smoking may be predictive factors for the effectiveness of oral morphine. Interestingly, respiratory rates in patients who reported the morphine to be effective decreased significantly after oral morphine administration, unlike the respiratory rates in "morphine-ineffective" patients.