Chronic care for heart failure patients: Who to refer back to the general practitioner?-Experiences of the Dutch integrated heart failure care model

OBJECTIVE

The number of patients with heart failure (HF) and corresponding burden of the healthcare system will increase significantly. The Dutch integrated model, 'Transmural care of HF Patients' was based on the European Society of Cardiology (ESC) guidelines and initiated to manage the increasing prevalence of HF patients in primary and secondary care and stimulate integrated care. It is unknown how many HF patients are eligible for back-referral to general practitioners (GPs), which is important information for the management of chronic HF care. This study aims to evaluate clinical practice of patients for whom chronic HF care can be referred from the cardiologist to the GP based on the aforementioned chronic HF care model.

DESIGN AND METHODS

A retrospective case record-based study was conducted, which included all chronic HF patients registered in the cardiology information systems of two different hospitals. Subsequently, 200 patients were randomly selected for evaluation. The following patients were considered eligible for referral to the GP: 1/Stable HF patients with reduced left ventricular ejection fraction (LVEF), 2/Stable HF patients with a recovered LVEF and 3/Stable HF patients with a preserved LVEF, 4/HF, palliative setting.

RESULTS

Of the 200 patients, 17% was considered eligible for referral to the GP. This group consisted of 5% patients with a reduced LVEF, 10.5% patients with recovered LVEF and 1.5% patients with a preserved LVEF. Main indicators for HF care by cardiologists were active cardiac disease other than HF (39.5%), recent admission for HF (29.5%) or a recent adjustment in HF medication (7.5%).

CONCLUSION

Applying the chronic HF care model of the 'Transmural care of HF patients' and the ESC-guidelines, results in an important opportunity to further optimise HF integrated care and to deal with the increasing number of HF patients referred to the hospital.

AI Algorithm to Predict Acute Coronary Syndrome in Prehospital Cardiac Care: Retrospective Cohort Study

BACKGROUND

Overcrowding of hospitals and emergency departments (EDs) is a growing problem. However, not all ED consultations are necessary. For example, 80% of patients in the ED with chest pain do not have an acute coronary syndrome (ACS). Artificial intelligence (AI) is useful in analyzing (medical) data, and might aid health care workers in prehospital clinical decision-making before patients are presented to the hospital.

OBJECTIVE

The aim of this study was to develop an AI model which would be able to predict ACS before patients visit the ED. The model retrospectively analyzed prehospital data acquired by emergency medical services' nurse paramedics.

METHODS

Patients presenting to the emergency medical services with symptoms suggestive of ACS between September 2018 and September 2020 were included. An AI model using a supervised text classification algorithm was developed to analyze data. Data were analyzed for all 7458 patients (mean 68, SD 15 years, 54% men). Specificity, sensitivity, positive predictive value (PPV), and negative predictive value (NPV) were calculated for control and intervention groups. At first, a machine learning (ML) algorithm (or model) was chosen; afterward, the features needed were selected and then the model was tested and improved using iterative evaluation and in a further step through hyperparameter tuning. Finally, a method was selected to explain the final AI model.

RESULTS

The AI model had a specificity of 11% and a sensitivity of 99.5% whereas usual care had a specificity of 1% and a sensitivity of 99.5%. The PPV of the AI model was 15% and the NPV was 99%. The PPV of usual care was 13% and the NPV was 94%.

CONCLUSIONS

The AI model was able to predict ACS based on retrospective data from the prehospital setting. It led to an increase in specificity (from 1% to 11%) and NPV (from 94% to 99%) when compared to usual care, with a similar sensitivity. Due to the retrospective nature of this study and the singular focus on ACS it should be seen as a proof-of-concept. Other (possibly life-threatening) diagnoses were not analyzed. Future prospective validation is necessary before implementation.

Prehospital triage of patients with acute cardiac complaints: study protocol of HART-c, a multicentre prospective study

INTRODUCTION

Emergency department (ED) overcrowding is a major healthcare problem associated with worse patient outcomes and increased costs. Attempts to reduce ED overcrowding of patients with cardiac complaints have so far focused on in-hospital triage and rapid risk stratification of patients with chest pain at the ED. The Hollands-Midden Acute Regional Triage-Cardiology (HART-c) study aimed to assess the amount of patients left at home in usual ambulance care as compared with the new prehospital triage method. This method combines paramedic assessment and expert cardiologist consultation using live monitoring, hospital data and real-time admission capacity.

METHODS AND ANALYSIS

Patients visited by the emergency medical services (EMS) for cardiac complaints are included. EMS consultation consists of medical history, physical examination and vital signs, and ECG measurements. All data are transferred to a newly developed platform for the triage cardiologist. Prehospital data, in-hospital medical records and real-time admission capacity are evaluated. Then a shared decision is made whether admission is necessary and, if so, which hospital is most appropriate. To evaluate safety, all patients left at home and their general practitioners (GPs) are contacted for 30-day adverse events.

ETHICS AND DISSEMINATION

The study is approved by the LUMC's Medical Ethics Committee. Patients are asked for consent for contacting their GPs. The main results of this trial will be disseminated in one paper.

DISCUSSION

The HART-c study evaluates the efficacy and feasibility of a prehospital triage method that combines prehospital patient assessment and direct consultation of a cardiologist who has access to live-monitored data, hospital data and real-time hospital admission capacity. We expect this triage method to substantially reduce unnecessary ED visits.

QT interval variability and heart rate turbulence are associated with clinical characteristics in congenital heart disease patients with a systemic right ventricle

BACKGROUND

QT interval variability (QTV) and heart rate turbulence (HRT) are measures of cardiac autonomic function, which, when abnormal, are correlated with ventricular arrhythmias and worse clinical outcome. This study aims to evaluate QTV and HRT in patients with a systemic right ventricle (RV) and to assess correlations with clinical characteristics.

METHODS

In a retrospective cohort study, QTV and HRT were derived from 24-h Holter registrations of patients with a systemic RV and healthy controls. QTV and HRT were compared between groups. In patients, the association between QTV, HRT, and clinical characteristics was assessed.

RESULTS

Holter recordings from 40 patients (mean age 40 years, 16 females) and 37 healthy controls (mean age 42 years, 21 females) were analyzed. Groups were comparable in terms of age and sex. QTV was increased in patients compared with controls (p < 0.001), HRT did not differ significantly between the groups. Increased QTV and decreased HRT correlated with medication use, especially of diuretics, and with clinical events, particularly supraventricular arrhythmias. Increased QTV correlated with reduced systemic RV function. Decreased HRT was independently associated with a larger number of past clinical events (estimate -0.33, 95% CI -0.63 to -0.02, p = 0.037). QTV was higher in women in both patients and controls (p = 0.041 and p = 0.034, respectively).

CONCLUSIONS

QTV and HRT are associated with clinical factors and events in patients with a systemic RV. Further studies are mandatory to confirm their prognostic value.

Association between reduced heart rate variability components and supraventricular tachyarrhythmias in patients with a systemic right ventricle

BACKGROUND

Patients with a systemic right ventricle are prone to develop heart failure. Abnormal heart rate variability (HRV), a measure of autonomic dysfunction, is associated with morbidity and mortality in patients with left ventricular failure. The association between HRV and supraventricular arrhythmias (SVTs), which are associated with adverse events in this population, was assessed.

METHODS

24-Hour Holter recordings of patients with a systemic right ventricle and healthy controls were analysed in a retrospective cohort study. HRV was calculated and compared between groups. Correlation coefficients were determined for HRV variables and clinical characteristics. The relation between HRV and SVTs was investigated with linear regression.

RESULTS

The patient group included 29 patients (69%) late after Mustard or Senning correction for transposition of the great arteries, and 13 patients with congenitally corrected transposition of the great arteries (31%). The control group included 38 subjects. HRV was significantly lower in patients compared with controls. In the patient group, lower SDANN (standard deviation of the average NN intervals calculated over 5-minute intervals) was independently associated with a higher number of supraventricular arrhythmias (95% CI -0.03 to -0.0004, p = 0.045). In exploratory correlation analysis, several HRV variables correlated with echocardiographic systemic right ventricular function (rho = 0.36, p = 0.02 for SDANN), and exercise capacity (rho = 0.39, p = 0.05 for SDANN).

CONCLUSION

In patients with a systemic right ventricle, HRV is lower compared with controls and (SDANN) is independently associated with supraventricular arrhythmias.

P3503Transcriptome changes in atrial myocytes during the transition from a proliferative into a contractile phenotype and vice versa

Background

iAM-1 cells are conditionally immortalized neonatal rat atrial myocytes allowing toggling between proliferative and contractile phenotypes by a single-component change in culture medium composition. In the absence of proliferation stimuli, the cells synchronously differentiate into functional cardiomyocytes. Following re-expression of the immortalization factor, the fully differentiated iAM-1 cells dedifferentiate and start to proliferate again.

Purpose

The aim of our study was to investigate the changes in gene expression profile in iAM-1 cells during one round of cardiac differentiation and dedifferentiation in order to identify potential (new) regulators of atrial myocyte differentiation and proliferation.

Methods

RNA sequencing was performed on iAM-1 cells at 9 time points during one cycle of cardiomyogenic differentiation and dedifferentiation (20 million 150-bp paired-end reads per sample, 4 samples per time point). The resulting sequence data were analysed by EdgeR. Hierarchical clustering and principle component analysis were performed in R. GO category enrichment was determined using DAVID.

Results

Approximately 13,000 genes were extracted from the RNA sequencing analysis. In general, dynamic changes in mRNA levels during the transition from a proliferative into a contractile phenotype opposed those that occurred when differentiated iAM-1 were re-exposed to proliferation stimuli. These inverse trends were most evident for genes involved in cell cycle progression, DNA replication, sarcomere formation and cardiac contraction. Moreover, the RNA-SEQ data allowed us to make a distinction between genes contributing to the early and late phases of cardiomyogenic differentiation and dedifferentiation and to identify similarities and differences in the transcriptional programs underlying the cardiomyogenic differentiation of iAM-1 cells versus those of embryonic stem cells and induced pluripotent stem cells. The transcriptome analysis also unveiled several genes with potentially important and previously unrecognized roles in cardiomyocyte differentiation and proliferation.

iAM-1 differentiation and dedifferention

Conclusions

Due to their ability to homogenously and synchronously differentiate and dedifferentiate, iAM-1 cells offer unique new insights into the transcriptional regulation of cardiomyocyte differentiation and proliferation.

Time course, predictors and clinical implications of stent thrombosis following primary angioplasty

Primary percutaneous coronary intervention (pPCI) has improved survival as compared to thrombolysis. Concerns still remain regarding the risk of stent thrombosis in the setting of STEMI, especially after drugeluting stent (DES) implantation. Therefore, the aim of this study was to report on the timing of stent thrombosis (ST) with both DES and bare metal stents (BMS) and its prognostic significance in patients undergoing pPCI. The Drug-Eluting Stent in Primary Angioplasty (DESERT) cooperation is based on a pooled database including individual data of randomised trials that evaluate the long-term safety and effectiveness of DES as compared to BMS in patients undergoing pPCI for STEMI. Follow-up data were collected for 3–6 years after the procedure. ST was defined as definite or probable, based on the ARC definition. The study population consists of 6,274 STEMI patients undergoing primary angioplasty with BMS or DES. At 1201±440 days, ST occurred in 267 patients (4.25%). Most of the events were acute or subacute (within 30 days) and very late (> 1 years), with different distribution between DES vs BMS. Patients with ST were more often diabetic (21.7% vs 15.1%, p=0.005), more frequently had post-procedural TIMI 0–2 flow (14.0% vs 9.3%, p = 0.01), and were less often treated with dual antiplatelet therapy at one year follow-up. Diabetes (p = 0.036), post-procedural TIMI 0–2 Flow (p = 0.013) and ischaemia time > 6 hours (p = 0.03) were independent predictors of ST. Post-procedural TIMI 0–2 flow (p = 0.001) and ischaemia time > 6 hours (p < 0.001) were independent predictors of early ST, ischaemia time > 6 hours (p=0.05) was independent predictor of late ST, whereas diabetes (p = 0.022) and use of DES (p=0.002) were independent predictors of very late ST. ST was associated with a significantly higher mortality (23.6% vs 6%, p < 0.001). The greatest impact on mortality was observed with subacute (40.4%) and late (20.9%) ST, as compared to acute (12.5%) and very late (9.1%) ST. ST was an independent predictor of mortality (HR [95%CI]=3.73 [2.75–5.07], p < 0.001). In conclusion, ST occurs relatively frequently also beyond the first year for up to six years after pPCI in STEMI, with higher late occurrence rates among patients treated with first generation DES. ST after pPCI is a powerful predictor of mortality, especially subacute ST.

Impact of hypertension on clinical outcome in STEMI patients undergoing primary angioplasty with BMS or DES: insights from the DESERT cooperation

BACKGROUND

Hypertension is a well known risk factor for atherosclerosis. However, data on the prognostic impact of hypertension in patients with ST elevation myocardial infarction (STEMI) are inconsistent and mainly related to studies performed in the thrombolytic era, with very few data in patients undergoing primary angioplasty. Therefore, the aim of the current study was to evaluate the impact hypertension on clinical outcome in STEMI patients undergoing primary PCI with BMS or DES.

METHODS

Our population is represented by 6298 STEMI patients undergoing primary angioplasty included in the DESERT database from 11 randomized trials comparing DES vs BMS for STEMI.

RESULTS

Hypertension was observed in 2764 patients (43.9%), and associated with ageing (p<0.0001), female gender (p<0.001), diabetes (p<0.0001), hypercholesterolemia (p<0.0001), previous MI (p=0.002), previous revascularization (p=0.002), longer time-to-treatment (p<0.001), preprocedural TIMI 3 flow, and with a lower prevalence of smoking (41% vs 53.9%, p<0.001) and anterior MI (42% vs 45.9%, p=0.002). Hypertension was associated with impaired postprocedural TIMI 0-2 flow (Adjusted OR [95% CI]=1.22 [1.01-1.47], p=0.034). At a follow-up of 1,201 ± 440 days, hypertension was associated with higher mortality (adjusted HR [95% CI]=1.24 [1.01-1.54], p=0.048), reinfarction (adjusted HR [95% CI]=1.31 [1.03-1.66], p=0.027), stent thrombosis (adjusted HR [95% CI]=1.29 [0.98-1.71], p=0.068) and TVR (adjusted HR [95% CI]=1.22 [1.04-1.44], p=0.013).

CONCLUSIONS

This study showed that among STEMI patients undergoing primary angioplasty with DES or BMS, hypertension is independently associated with impaired epicardial reperfusion, mortality, reinfarction and TVR, and a trend in higher ST.

Drug-eluting stents in patients with anterior STEMI undergoing primary angioplasty: a substudy of the DESERT cooperation

BACKGROUND

Several concerns have emerged on the higher risk of in-stent thrombosis after drug-eluting stent (DES) implantation, especially in the setting of STEMI patients. Few data have even been reported in high-risk patients, such as those with anterior MI. Therefore this represents the aim of the current study.

METHODS

The literature was scanned by formal searches of electronic databases (MEDLINE and CENTRAL). We examined all completed randomized trials of DES for STEMI. The following key words were used for study selection: randomized trial, myocardial infarction, reperfusion, primary angioplasty, stenting, DES, sirolimus-eluting stent (SES), Cypher, paclitaxel-eluting stent (PES), Taxus. No language restrictions were enforced.

RESULTS

Individual patient's data were obtained from 11 out of 13 trials, including a total of 2,782 patients with anterior MI [1,739 or 62.5% randomized to DES and 1,043 or 37.5% randomized to bare-metal stent (BMS)]. At long-term follow-up, no significant benefit was observed with DES as compared to BMS in terms of mortality [9.8 vs 10.9%, HR (95% CI) = 0.81 (0.61, 1.07), p = 0.13, p heterogeneity = 0.18], reinfarction [8.8 vs 6.4%, respectively; HR (95% CI) = 1.14 (0.80, 1.61), p = 0.47, p heterogeneity = 0.82], and stent thrombosis [5.6 vs 5%, OR (95% CI) = 0.88 (0.59, 1.30), p = 0.51, p heterogeneity = 0.65], whereas DES was associated with a significant reduction in terms of target-vessel revascularization (TVR) [13.7 vs 23.4%; OR (95% CI) = 0.56 (0.46, 0.69), p < 0.0001, p het = 0.81] that was observed at both early (within 1 year) [7 vs 14.7%, HR (95% CI) = 0.56 (0.46, 0.69), p < 0.0001, p het = 0.81] and late (>1 year) follow-up [7.2 vs 9%, HR (95% CI) = 0.67 (0.47, 0.96), p = 0.03, p het = 0.96].

CONCLUSIONS

This study showed that among patients with anterior STEMI undergoing primary angioplasty, SES and PES, as compared to BMS, are associated with a significant reduction in TVR at long-term follow-up. No concerns were found with the use of first-generation DES in terms of mortality.