Long-term reliability of the phospholamban (PLN) p.(Arg14del) risk model in predicting major ventricular arrhythmia: a landmark study.

AIMS: Recently, a genetic variant-specific prediction model for phospholamban (PLN) p.(Arg14del)-positive individuals was developed to predict individual major ventricular arrhythmia (VA) risk to support decision-making for primary prevention implantable cardioverter defibrillator (ICD) implantation. This model predicts major VA risk from baseline data, but iterative evaluation of major VA risk may be warranted considering that the risk factors for major VA are progressive. Our aim is to evaluate the diagnostic performance of the PLN p.(Arg14del) risk model at 3-year follow-up. METHODS AND RESULTS: We performed a landmark analysis 3 years after presentation and selected only patients with no prior major VA. Data were collected of 268 PLN p.(Arg14del)-positive subjects, aged 43.5 ± 16.3 years, 38.9% male. After the 3 years landmark, subjects had a mean follow-up of 4.0 years (± 3.5 years) and 28 (10%) subjects experienced major VA with an annual event rate of 2.6% [95% confidence interval (CI) 1.6-3.6], defined as sustained VA, appropriate ICD intervention, or (aborted) sudden cardiac death. The PLN p.(Arg14del) risk score yielded good discrimination in the 3 years landmark cohort with a C-statistic of 0.83 (95% CI 0.79-0.87) and calibration slope of 0.97. CONCLUSION: The PLN p.(Arg14del) risk model has sustained good model performance up to 3 years follow-up in PLN p.(Arg14del)-positive subjects with no history of major VA. It may therefore be used to support decision-making for primary prevention ICD implantation not merely at presentation but also up to at least 3 years of follow-up.

ECG-only explainable deep learning algorithm predicts the risk for malignant ventricular arrhythmia in phospholamban cardiomyopathy.

BACKGROUND: Phospholamban (PLN) p.(Arg14del) variant carriers are at risk for development of malignant ventricular arrhythmia (MVA). Accurate risk stratification allows timely implantation of intracardiac defibrillators and is currently performed with a multimodality prediction model. OBJECTIVE: This study aimed to investigate whether an explainable deep learning-based approach allows risk prediction with only electrocardiogram (ECG) data. METHODS: A total of 679 PLN p.(Arg14del) carriers without MVA at baseline were identified. A deep learning-based variational auto-encoder, trained on 1.1 million ECGs, was used to convert the 12-lead baseline ECG into its FactorECG, a compressed version of the ECG that summarizes it into 32 explainable factors. Prediction models were developed by Cox regression. RESULTS: The deep learning-based ECG-only approach was able to predict MVA with a C statistic of 0.79 (95% CI, 0.76-0.83), comparable to the current prediction model (C statistic, 0.83 [95% CI, 0.79-0.88]; P = .054) and outperforming a model based on conventional ECG parameters (low-voltage ECG and negative T waves; C statistic, 0.65 [95% CI, 0.58-0.73]; P < .001). Clinical simulations showed that a 2-step approach, with ECG-only screening followed by a full workup, resulted in 60% less additional diagnostics while outperforming the multimodal prediction model in all patients. A visualization tool was created to provide interactive visualizations (https://pln.ecgx.ai). CONCLUSION: Our deep learning-based algorithm based on ECG data only accurately predicts the occurrence of MVA in PLN p.(Arg14del) carriers, enabling more efficient stratification of patients who need additional diagnostic testing and follow-up.

Outpatient treatment of worsening heart failure with intravenous diuretics: first results from a multicentre 2-year experience.

AIMS: The aim of this study is to examine the safety and efficacy of outpatient treatment of worsening heart failure (WHF) with intravenous diuretics. METHODS AND RESULTS: This is a multicentre retrospective observational research study. Patients with all types of heart failure (HF) were included: heart failure with reduced ejection fraction (HFrEF), heart failure with mildly reduced ejection fraction (HFmrEF), and heart failure with preserved ejection fraction (HFpEF). Patients included in this study were 18 years or older, had symptoms of WHF, had weight gain of more than 2 kg, and were not responding to uptitrating of oral diuretic therapy. Patients were treated for one or more days at the outpatient department with administration of intravenous loop diuretics with or without a bolus. In this study, 259 patients were included (mean age of 76 years, mean left ventricular ejection fraction of 41%). Rehospitalization rates for HF were 30.5% and 53.3%, respectively, at 30 days and 1 year. All-cause mortality was 5.8% and 26.3%, respectively, at 30 days and 1 year. Rehospitalization rates for HF and all-cause mortality were highest in patients with HFrEF. In a total of 322 individual outpatient treatments with intravenous diuretics, only one adverse event was registered. CONCLUSIONS: Outpatient treatment with intravenous diuretics of patients with WHF is a safe alternative strategy compared with the same treatment in hospitalized patients. However, only non-randomized data are available and rehospitalization rates for this group with WHF are high. No data are available on the best selection criteria and the cost-effectiveness of outpatient treatment with intravenous diuretics.

Prediction of ventricular arrhythmia in phospholamban p.Arg14del mutation carriers-reaching the frontiers of individual risk prediction.

AIMS: This study aims to improve risk stratification for primary prevention implantable cardioverter defibrillator (ICD) implantation by developing a new mutation-specific prediction model for malignant ventricular arrhythmia (VA) in phospholamban (PLN) p.Arg14del mutation carriers. The proposed model is compared to an existing PLN risk model. METHODS AND RESULTS: Data were collected from PLN p.Arg14del mutation carriers with no history of malignant VA at baseline, identified between 2009 and 2020. Malignant VA was defined as sustained VA, appropriate ICD intervention, or (aborted) sudden cardiac death. A prediction model was developed using Cox regression. The study cohort consisted of 679 PLN p.Arg14del mutation carriers, with a minority of index patients (17%) and male sex (43%), and a median age of 42 years [interquartile range (IQR) 27-55]. During a median follow-up of 4.3 years (IQR 1.7-7.4), 72 (10.6%) carriers experienced malignant VA. Significant predictors were left ventricular ejection fraction, premature ventricular contraction count/24 h, amount of negative T waves, and presence of low-voltage electrocardiogram. The multivariable model had an excellent discriminative ability {C-statistic 0.83 [95% confidence interval (CI) 0.78-0.88]}. Applying the existing PLN risk model to the complete cohort yielded a C-statistic of 0.68 (95% CI 0.61-0.75). CONCLUSION: This new mutation-specific prediction model for individual VA risk in PLN p.Arg14del mutation carriers is superior to the existing PLN risk model, suggesting that risk prediction using mutation-specific phenotypic features can improve accuracy compared to a more generic approach.

Outpatient treatment of worsening heart failure with intravenous and subcutaneous diuretics: a systematic review of the literature.

AIMS: In the coming decade, heart failure (HF) represents a major global healthcare challenge due to an ageing population and rising prevalence combined with scarcity of medical resources and increasing healthcare costs. A transitional care strategy within the period of clinical worsening of HF before hospitalization may offer a solution to prevent hospitalization. The outpatient treatment of worsening HF with intravenous or subcutaneous diuretics as an alternative strategy for hospitalization has been described in the literature. METHODS AND RESULTS: In this systematic review, the available evidence for the efficacy and safety of outpatient treatment with intravenous or subcutaneous diuretics of patients with worsening HF is analysed. A search was performed in the electronic databases MEDLINE and EMBASE. Of the 11 included studies 10 were single-centre, using non-randomized, observational registries of treatment with intravenous or subcutaneous diuretics for patients with worsening HF with highly variable selection criteria, baseline characteristics, and treatment design. One study was a randomized study comparing subcutaneous furosemide with intravenous furosemide. In a total of 984 unique individual patients treated in the reviewed studies, only a few adverse events were reported. Re-hospitalization rates for HF at 30 and 180 days were 28 and 46%, respectively. All-cause re-hospitalization rates at 30 and 60 days were 18-37 and 22%, respectively. The highest HF re-hospitalization was 52% in 30 days in the subcutaneous diuretic group and 42% in 30 days in the intravenous diuretic group. CONCLUSIONS: The reviewed studies present practice-based results of treatment of patients with worsening HF with intravenous or subcutaneous diuretics in an outpatient HF care unit and report that it is effective by relieving symptoms with a low risk of adverse events. The studies do not provide satisfactory evidence for reduction in rates of re-hospitalization or improvement in mortality or quality of life. The conclusions drawn from these studies are limited by the quality of the individual studies. Prospective randomized studies are needed to determine the safety and effectiveness of outpatient intravenous or subcutaneous diuretic treatment for patient with worsening HF.

N-Terminal Pro-B-Type Natriuretic Peptide (NT-proBNP) Measurements Until a 30% Reduction Is Attained During Acute Decompensated Heart Failure Admissions and Comparison With Discharge NT-proBNP Levels: Implications for In-Hospital Guidance of Treatment.

BACKGROUND: A >30% N-terminal pro-B-type natriuretic peptide (NT-proBNP) reduction at discharge in acute decompensated heart failure (ADHF) predicts a favorable prognosis. To study the feasibility of guiding ADHF treatment by measuring NT-proBNP well before discharge, we assessed at which moment during hospitalization patients attain a NT-proBNP reduction of >30% (target) and whether this target is still attained at discharge. METHODS: Twenty-five consecutive ADHF patients with NT-proBNP >1,700 ng/L were included (original cohort). NT-proBNP was measured daily until the target was attained, at clinical stability, and at discharge and was analyzed as percentages of patients on target. For comparison purposes, the same analysis was performed in individual patient data from 2 other ADHF cohorts (42 and 111 patients, respectively), in which NT-proBNP was measured from admission to day 3 and at discharge. RESULTS: In the original cohort of 25 patients (median age 70 years, 40% male), the cumulative percentage of patients attaining the target increased gradually during admission to 22 patients (88%) in a median of 3 days (interquartile range 2-5). In the comparison cohorts, a similar course was observed in patients attaining the target before discharge. Compared with levels measured at days 2 and 3, rebound NT-proBNP increases to levels off-target at discharge were seen in up to 33% of patients in the original and comparison cohorts. CONCLUSION: A target >30% NT-proBNP reduction is gradually attained before discharge, and rebound NT-proBNP increases to levels off-target occur in up to 33% of ADHF patients who initially attained target early during admission.

Rationale and design of PRIMA II: A multicenter, randomized clinical trial to study the impact of in-hospital guidance for acute decompensated heart failure treatment by a predefined NT-PRoBNP target on the reduction of readmIssion and Mortality rAtes.

BACKGROUND: Hospital admissions for acute decompensated heart failure (ADHF) are frequent and are accompanied by high percentages of mortality and readmissions. Brain natriuretic peptide (BNP) and the inactive N-terminal fragment of its precursor proBNP (NT-proBNP) are currently the best predictors of prognosis in heart failure (HF) patients. In the setting of chronic HF, studies that performed guidance of therapy by NT-proBNP have had only limited success. For patients with ADHF, retrospective studies have shown that a reduction in NT-proBNP of ≤30% during admission is a significant predictor of HF readmissions and mortality. These data suggest a role for NT-proBNP guidance in the setting of ADHF admissions. STUDY DESIGN: The PRIMA II is an investigator-initiated, multicenter, randomized, controlled, prospective 2-arm trial that investigates the impact of inhospital guidance for ADHF treatment by a predefined NT-proBNP target (>30% reduction during admission) on the reduction of readmission and mortality rates within 180 days. Consenting ADHF patients with NT-proBNP levels of >1,700 ng/L are eligible. After achieving clinical stability, a total of 340 patients are randomized to either NT-proBNP-guided or conventional treatment (1:1). The primary end point is dual, that is, a composite of all-cause mortality and readmission for HF in 180 days and the number of days alive out of hospital in 180 days. Secondary end points are readmissions and/or mortality in 180 days, cost effectiveness of hospitalization days in 180 days, readmissions and mortality in 90 days, and quality of life. CONCLUSION: The PRIMA II trial aims at providing scientific evidence for the use of NT-proBNP-guided therapy compared with conventional treatment in patients admitted for ADHF.