Lithuanian Echocardiography Study of Dyspnea in Acute Settings

Heart failure (HF) is believed to be the modern-day epidemic due to increasing incidence, impaired long-term prognosis and huge economic burden. With the ageing population the impact of HF on health care resources is on the rise. The course of the disease is characterized by episodes of acute decompensation that mark a significant turning point in the progress of the disease, with in-hospital mortality rates as high as 10%. Acute heart failure (AHF) is a gradual or rapid change in HF signs and symptoms, requiring urgent medical therapies. Acute heart failure is estimated to be the most costly and the most frequent cause of admission to emergency wards. Emergency department (ED) is the primary setting where initial AHF management takes place. However, strong evidence for diagnostics and management of this grave condition is still lacking. Even less is known about the prevalence, diagnosis and management of acute right ventricular failure (RVF).

A patient presenting to the ED with acute dyspnea has to undergo numerous procedures in order to differentiate the diagnosis between AHF, chronic obstructive pulmonary disease, pneumonia, pulmonary embolism and other etiologies. Moreover, the majority of HF patients suffer from comorbidities that make the diagnostic process even more challenging. Due to numerous exams and tests, the initial management of these patients may be delayed, resulting in an extended hospital length of stay, increased rate of complications and death. The clinical, hemodynamic and neurohormonal features of heart failure are different in specific patient populations and depend on age, sex, race, left ventricular ejection fraction and co-existent right ventricular (RV) dysfunction as well as many other factors.

Cardiac biomarkers are easily reproducible and objective laboratory tests that could help to improve early AHF diagnosis and risk stratification. However, reported data suggest varying prognostic and diagnostic values of natriuretic peptides, such as N-type natriuretic peptide (BNP), N-terminal pro B-type natriuretic peptide (NT-proBNP), MR pro-atrial natriuretic peptide (MR-proANP), as well as regional differences of these markers. Specific biomarkers of RVF have not yet been described, thus a search of novel serologic markers that could rapidly and reliably help diagnose acute RVF is a very important scientific task in cardiology. Furthermore, the knowledge on the incidence of RVF syndrome as well as the diagnostic and prognostic values of ultrasound RV structural and functional parameters is scarce. During this study the RV-focused ultrasound examination will be performed in the early hospitalization period, and blood samples will be taken and frozen at the same time. Up to 15 novel cardiac, vascular, renal impairment and inflammation biomarkers in plasma samples during acute phase of RVF will be investigated during the study in France, INSERM laboratory. The study will be unique as it will aggregate large scale observational and biomarkers database of AHF patients in Lithuania together with innovative ultrasound parameters of RV failure (quantitative parameters of RV systolic function and deformation).

The aim of this project is to find the specific novel biomarkers of acute heart failure (AHF), to evaluate their diagnostic and prognostic role in association with echocardiographic parameters of AHF.

The primary endpoint is 1-year all-cause mortality and rehospitalization.

Secondary endpoints are:

1. in-hospital all-cause mortality
2. post-discharge 1 and 3 months all-cause mortality and rehospitalization
3. post-discharge 1 and 3 months cardiovascular mortality and rehospitalization
4. one-year cardiovascular mortality and rehospitalization.

Objectives of this project are:

1. To create a database of patients hospitalized due to acute heart failure in Lithuania, integrated to GREAT (Global Research on Acute Conditions Team) network database;
2. To compare the diagnostic and prognostic value of novel cardiac, vascular, renal insufficiency and inflammation biomarkers in the Lithuanian patient cohort to other countries in the GREAT network;
3. To determine the demographic, clinical and treatment characteristics as well as short and long term outcome of patients hospitalized due to AHF in Lithuania and other GREAT network countries;
4. To evaluate the epidemiology of RVF together with clinical features and outcome of patients in a cohort of Lithuanian acute heart failure (HF) patients;
5. To estimate a correlation between ultrasound parameters of RV structure and function and novel cardiac, vascular, renal and inflammation biomarkers in acute period of HF;
6. To identify novel ultrasound parameters of RV structure and function parameters and biomarkers predicting a risk of 1 year mortality after hospitalization;
7. To create an algorithm of RV failure diagnostics and risk stratification based on the diagnostic and prognostic value of detected echocardiographic parameters and biomarkers.

Observational studies and recent meta-analyses indicate that in acute conditions RVF may be as frequent as let ventricular failure (LVF) and is associated with markedly poor prognosis. Largely empiric knowledge in emergency medicine suggests that right and left ventricular failure requires different therapeutic approaches, including disparate principles of intravenous treatment, due to distinct hemodynamic impairment. The outcome of RVF is largely dependent on the underlying cause, resulting in either an acute or chronic presentation.

Novel biomarkers can help identify the underlying conditions in AHF. These include myocardial injury markers such as copeptine, proenkephalin, high sensitivity troponin T, troponin I, brain natriuretic peptide (BNP), N-terminal-proBNP; renal and hepatic involvement markers such as adrenomedullin, neutrophil gelatinase-associated lipocalin (NGAL), L-type fatty acid binding protein (L-FABP), galectin-3, soluble ST2, cystatin C; inflammatory markers such as C-reactive protein, interleukine 6, procalcitonin. These markers could help evaluate end-organ involvement, as well as the extent of myocardial remodeling, and in return provide state-of-the-art tailored patient care. Specific biomarkers of RV involvement or dysfunction have not yet been described, therefore identification of such biomarkers would allow to accelerate the diagnosis of RVF and initiate specific treatment.

Echocardiography is a potent and accessible technique for the diagnosis of AHF in an acute setting. Echocardiography also provides information about the mechanisms of AHF as well as alternative causes of dyspnea. Echocardiographic parameters of RV structure and function are of particular interest since not much data is available on acute RVF. Quantitative parameters of RV systolic and diastolic function, RV wall deformation or notional hemodynamic parameters could potentially be useful for diagnosis and selection of urgent treatment tactics. In the current literature there are no publications about the diagnostic and prognostic value of RV parameters, especially about novel echocardiographic parameters (strain rate, speckle tracking), in the early phase of exacerbated heart failure.

Global Research on Acute Conditions Teal (GREAT) Association is an international network among experts operating in the management of acute clinical conditions in the field of emergency medicine and doing research through the concept of translational medicine. This network integrates research inputs from basic sciences and interventional epidemiology to optimize both patient care and preventive measures. Moreover, one of the main objectives of the GREAT association is to standardize the clinical and organizational system approach in acute conditions disease management all over the world, with the concept of globalization medicine. Up to this day there has not been any large multicenter observational and biomarkers studies in Lithuania in the field of AHF. Our study creates a unique opportunity to join the worldwide GREAT network and its patient database, that could potentially contain up to 50 000 patients.