Left ventricular remodelling and prognosis after discharge in new-onset acute heart failure with reduced ejection fraction

Machine learning score to predict in-hospital outcomes in patients hospitalized in cardiac intensive care unit

Aims

Although some scores based on traditional statistical methods are available for risk stratification in patients hospitalized in cardiac intensive care units (CICUs), the interest of machine learning (ML) methods for risk stratification in this field is not well established. We aimed to build an ML model to predict in-hospital major adverse events (MAE) in patients hospitalized in CICU.

Methods and results

In April 2021, a French national prospective multicentre study involving 39 centres included all consecutive patients admitted to CICU. The primary outcome was in-hospital MAE, including death, resuscitated cardiac arrest, or cardiogenic shock. Using 31 randomly assigned centres as an index cohort (divided into training and testing sets), several ML models were evaluated to predict in-hospital MAE. The eight remaining centres were used as an external validation cohort. Among 1499 consecutive patients included (aged 64 ± 15 years, 70% male), 67 had in-hospital MAE (4.3%). Out of 28 clinical, biological, ECG, and echocardiographic variables, seven were selected to predict MAE in the training set (n = 844). Boosted cost-sensitive C5.0 technique showed the best performance compared with other ML methods [receiver operating characteristic area under the curve (AUROC) = 0.90, precision-recall AUC = 0.57, F1 score = 0.5]. Our ML score showed a better performance than existing scores (AUROC: ML score = 0.90 vs. Thrombolysis In Myocardial Infarction (TIMI) score: 0.56, Global Registry of Acute Coronary Events (GRACE) score: 0.52, Acute Heart Failure (ACUTE-HF) score: 0.65; all P < 0.05). Machine learning score also showed excellent performance in the external cohort (AUROC = 0.88).

Conclusion

This new ML score is the first to demonstrate improved performance in predicting in-hospital outcomes over existing scores in patients admitted to the intensive care unit based on seven simple and rapid clinical and echocardiographic variables.

Trial Registration

ClinicalTrials.gov Identifier: NCT05063097.

Role of NLRP3 Inflammasome in Heart Failure Patients Undergoing Cardiac Surgery as a Potential Determinant of Postoperative Atrial Fibrillation and Remodeling: Is SGLT2 Cotransporter Inhibition an Alternative for Cardioprotection?

In heart failure (HF) patients undergoing cardiac surgery, an increased activity of mechanisms related to cardiac remodeling may determine a higher risk of postoperative atrial fibrillation (POAF). Given that atrial fibrillation (AF) has a negative impact on the course and management of HF, including the need for anticoagulation therapy, identifying the factors associated with AF occurrence after cardiac surgery is crucial for the prognosis of these patients. POAF is thought to occur when various clinical and biochemical triggers act on susceptible cardiac tissue (first hit), with oxidative stress and inflammation during cardiopulmonary bypass (CPB) surgery being potential contributing factors (second hit). However, the molecular mechanisms involved in these processes remain poorly characterized. Recent research has shown that patients who later develop POAF often have pre-existing abnormalities in calcium handling and activation of NLRP3-inflammasome signaling in their atrial cardiomyocytes. These molecular changes may make cardiomyocytes more susceptible to spontaneous Ca2+-releases and subsequent arrhythmias, particularly when exposed to inflammatory mediators. Additionally, some clinical studies have linked POAF with elevated preoperative inflammatory markers, but there is a need for further research in order to better understand the impact of CPB surgery on local and systemic inflammation. This knowledge would make it possible to determine whether patients susceptible to POAF have pre-existing inflammatory conditions or cellular electrophysiological factors that make them more prone to developing AF and cardiac remodeling. In this context, the NLRP3 inflammasome, expressed in cardiomyocytes and cardiac fibroblasts, has been identified as playing a key role in the development of HF and AF, making patients with pre-existing HF with reduced ejection fraction (HFrEF) the focus of several clinical studies with interventions that act at this level. On the other hand, HFpEF has been linked to metabolic and non-ischemic risk factors, but more research is needed to better characterize the myocardial remodeling events associated with HFpEF. Therefore, since ventricular remodeling may differ between HFrEF and HFpEF, it is necessary to perform studies in both groups of patients due to their pathophysiological variations. Clinical evidence has shown that pharmacological therapies that are effective for HFrEF may not provide the same anti-remodeling benefits in HFpEF patients, particularly compared to traditional adrenergic and renin-angiotensin-aldosterone system inhibitors. On the other hand, there is growing interest in medications with pleiotropic or antioxidant/anti-inflammatory effects, such as sodium-glucose cotransporter 2 inhibitors (SGLT-2is). These drugs may offer anti-remodeling effects in both HFrEF and HFpEF by inhibiting pro-inflammatory, pro-oxidant, and NLRP3 signaling pathways and their mediators. The anti-inflammatory, antioxidant, and anti-remodeling effects of SGLT-2 i have progressively expanded from HFrEF and HFpEF to other forms of cardiac remodeling. However, these advances in research have not yet encompassed POAF despite its associations with inflammation, oxidative stress, and remodeling. Currently, the direct or indirect effects of NLRP3-dependent pathway inhibition on the occurrence of POAF have not been clinically assessed. However, given that NLRP3 pathway inhibition may also indirectly affect other pathways, such as inhibition of NF-kappaB or inhibition of matrix synthesis, which are strongly linked to POAF and cardiac remodeling, it is reasonable to hypothesize that this type of intervention could play a role in preventing these events.

Joint modelling of longitudinal processes and time-to-event outcomes in heart failure: systematic review and exemplar examining the relationship between serum digoxin levels and mortality

BACKGROUND

Joint modelling combines two or more statistical models to reduce bias and increase efficiency. As the use of joint modelling increases it is important to understand how and why it is being applied to heart failure research.

METHODS

A systematic review of major medical databases of studies which used joint modelling within heart failure alongside an exemplar; joint modelling repeat measurements of serum digoxin with all-cause mortality using data from the Effect of Digoxin on Mortality and Morbidity in Patients with Heart Failure (DIG) trial.

RESULTS

Overall, 28 studies were included that used joint models, 25 (89%) used data from cohort studies, the remaining 3 (11%) using data from clinical trials. 21 (75%) of the studies used biomarkers and the remaining studies used imaging parameters and functional parameters. The exemplar findings show that a per unit increase of square root serum digoxin is associated with the hazard of all-cause mortality increasing by 1.77 (1.34-2.33) times when adjusting for clinically relevant covariates.

CONCLUSION

Recently, there has been a rise in publications of joint modelling being applied to heart failure. Where appropriate, joint models should be preferred over traditional models allowing for the inclusion of repeated measures while accounting for the biological nature of biomarkers and measurement error.

Myoglobin and left ventricular ejection fraction as predictive markers for death in children with fulminant myocarditis

BACKGROUND

Fulminant myocarditis (FM) is an inflammatory process of the myocardium and an important cause of cardiac dysfunction in children; it is characterized by rapid onset, acute progression, and high mortality. The study sought to describe the clinical characteristics and prognostic factors in children with FM.

METHODS

The study population consists of 37 consecutive patients admitted from May 2014 to December 2021 with a diagnosis of FM. According to the prognosis of children with FM during hospitalization, they were divided into "survival" group (25 cases) and "death" group (12 cases). A multivariate logistic regression analysis was performed to identify the independent predictors of in-hospital mortality in the patients, and receiver operating characteristic (ROC) curve was used to explore the predictive value of related factors.

RESULTS

The 37 children with FM had an average age of 8.35 ± 4.36 years old. Twenty-five of the patients survived and 12 died. Twenty-five of the children were discharged from the hospital after a series of active rescue treatments such as nutritional myocardial drugs, high-dose intravenous immunoglobulin (IVIG), glucocorticoids (GCs), temporary pacemaker (TP), extracorporeal membrane oxygenation (ECMO), and continuous renal replacement therapy (CRRT).Twelve of the children were classified into the death group because the resuscitation failed. The levels of procalcitonin (PCT), creatine kinase (CK), and myoglobin (MYO) in the death group were all higher than in the survival group (all P < 0.05), and the left ventricular ejection fraction (LVEF) in the death group was significantly lower than in the survival group (P = 0.002). The binary logistic regression analysis revealed that MYO [OR:1.006; 95%CI:(1-1.012); P = 0.045] and LVEF [OR: 0.876; 95% CI: (0.785-0.978); P = 0.019] were independent predictors of FM. ROC curve analysis showed that the area under ROC curve (AUC) of MYO and LVEF was [AUC:0.957; 95%CI:0.897~1] and [AUC:0.836; 95%CI:0.668~1], and the area under the combined ROC curve for MYO + LVEF was significantly higher than that for MYO or LVEF alone (P < 0.05), indicating that the MYO + LVEF combined diagnosis had a higher predictive value for FM.

CONCLUSION

The levels of MYO and LVEF can be markers for prognosis of FM and can effectively evaluate the disease severity. Their combination can improve forecast accuracy; thus, the detection of the above-mentioned indexes possesses a higher value for clinical applications.

Preventive implantable cardioverter defibrillator therapy in contemporary clinical practice: need for more stringent selection criteria

While the efficacy of the intracardiac defibrillators (ICDs) for primary prevention is not disputed, the relevant studies were carried out a long time ago. Most pertinent trials, including MADIT-II, SCD-Heft, and DEFINITE, recruited patients more than 20 years ago. Since then, improved therapeutic modalities including, in addition to cardiac resynchronization therapy, mineralocorticoid receptor antagonists, angiotensin receptor-neprilysin inhibitors, and, most recently, inhibitors of sodium-glucose cotransporter 2, have lowered present-day rates of mortality and of sudden cardiac death. Thus, nowadays, ICD therapy may be less effective than previously reported, and not as beneficial as many people currently believe. However, criteria for ICD implantation remain very inclusive. The patient must (only) be symptomatic and have ejection fraction (EF) ≤ 35%. The choice of EF 35% is notable because the average EF in all large trials was much lower, and clinical benefit was mainly limited to EF ≤ 30%. This EF cut-off value defines a substantial portion of potential ICD recipients. It seems therefore reasonable to limit ICD eligibility criteria in the EF range 30-35% to patients at highest risk only. We discuss and present some rational criteria to assist the clinician in improving risk stratification for preventive ICD implantation.

Left ventricular remodelling and prognosis after discharge in new-onset acute heart failure with reduced ejection fraction

Aims

This study aimed to investigate the left ventricular (LV) remodelling and long‐term prognosis of patients with new‐onset acute heart failure (HF) with reduced ejection fraction who were pharmacologically managed and survived until hospital discharge. We compared patients with ischaemic and non‐ischaemic aetiology.

Methods and results

This cohort study consisted of 111 patients admitted with new‐onset acute HF in the period 2008–2016 [62% non‐ischaemic aetiology, 48% supported by inotropes, vasopressors, or short‐term mechanical circulatory devices, and left ventricular ejection fraction (LVEF) at discharge 28% (interquartile range 22–34)]. LV dimensions, LVEF, and mitral valve regurgitation were used as markers for LV remodelling during up to 3 years of follow‐up. Both patients with non‐ischaemic and ischaemic HF had significant improvement in LVEF (P < 0.001 and P = 0.004, respectively) with significant higher improvement in those with non‐ischaemic HF (17% vs. 6%, P < 0.001). Patients with non‐ischaemic HF had reduction in LV end‐diastolic and end‐systolic diameters (6 and 10 mm, both P < 0.001), but this was not found in those with ischaemic HF [+3 mm (P = 0.09) and +2 mm (P = 0.07), respectively]. During a median follow‐up of 4.6 years, 98 patients (88%) did not reach the composite endpoint of LV assist device implantation, heart transplantation, or all‐cause mortality, with no difference between with ischaemic and non‐ischaemic HF [hazard ratio 0.69 (95% confidence interval 0.19–2.45)].

Conclusions

Patients with new‐onset acute HF with reduced ejection fraction discharged on optimal medical treatment have a good prognosis. We observed a considerable LV remodelling with improvement in LV function and dimensions, starting already at 6 months in patients with non‐ischaemic HF but not in their ischaemic counterparts.