HERCULeS

Supporting early diagnosis for diastolic heart failure

The challenge

Heart failure affects 26 million adults worldwide,[1] of which 6.5 million are in Europe.[2] Heart failure accounts for over 30% of all deaths due to cardiovascular disease and represents annual costs of more €10k per patient.[3] Heart failure readmission rates are also high, with approximately 25% of patients requiring hospital readmission within 30 days of discharge after acute episodes.[4]

Heart failure with preserved ejection fraction (HFpEF), also referred to as diastolic heart failure, represents around half of all heart failure cases.[5] Patients affected by this type of heart failure would greatly benefit from improved diastolic function analysis.

HFpEF survival rates remain low at 35-40% after 5 years,[6] due to the diversity of underlying causes and lack of effective treatment in latter disease stage. For this reason, early risk control intervention is important and to enable this, early and accurate diagnosis is crucial.

To diagnose HFpEF in its early stages, clinicians need to evaluate the ability of the left ventricle to fill with blood after the ejection phase. This is known as diastolic function. Cardiac ultrasound can be used to assess ejection performance (systolic function) but is not well-suited to assessing diastolic function.

Diastolic function can be assessed by measuring left ventricle stiffness, but this requires an invasive procedure, so it is not widely used. As an alternative, clinicians can combine several echocardiographic (heart ultrasound) measurements to assess diastolic function.[7] But these existing imaging alternatives are not sufficiently sensitive to successfully empower early intervention. To support the early diagnosis and treatment of HFpEF, there is a strong clinical need for new non-invasive tools to assess diastolic function and explore its pivotal role towards improving cardiac care.

The solution

The HERCULes project team have created a new solution that uses high frame rate imaging of the heart to assess myocardial stiffness as a diagnostic biomarker of diastolic function. This new diagnostic tool promises to support the early diagnosis of HFpEF.

The advent of massive parallel computing (where numerous computer processors simultaneously perform a set of coordinated computations in parallel) has enabled high frame rate echocardiographic recordings up to 5kHz, which is 100 times the frame rate of conventional imaging.[8] [9]

Imaging the heart at such high frame rate allows for the detection of waves along the cardiac wall caused by aortic and mitral valve closure.[10] The propagation speed of these waves depends on myocardial stiffness. So, measuring wave propagation speed can help to assess myocardial stiffness.

HERCULeS (high frame rate cardiac ultrasound) combines numerous imaging methodologies to enable high frame rate imaging of the heart. This allows clinicians to quantify wave propagation speed as a measure of myocardial stiffness, a biomarker of diastolic function.

Expected impact

As a new non-invasive, highly sensitive diagnostic tool, HERCULeS promises to support the early diagnosis of HFpEF, helping patients access treatment before the condition progresses, improving patient outcomes.

By offering a method that can detect HFpEF earlier in the disease process, HERCULeS could significantly improve quality of life and prognosis for heart failure patients affected across Europe. Receiving a diagnosis and being empowered to make lifestyle changes early in the disease could significantly alter the disease progression.

HERCULeS has the potential significantly reduce time‑to‑diagnosis, enabling population-wide screening and early intervention for HFpEF. This would lead to better patient management and more efficient clinical decision-making. Ultimately, this new solution promises to improve outcomes for heart failure patients and reduce overall health care costs, as patients would be more effectively treated early on.

References

[1] Bui, A.L., Horwich, T.B. and Fonarow, G.C. (2010). Epidemiology and risk profile of heart failure. Nature Reviews Cardiology, 8(1), 30–41.

[2] Tendera, M. (2005) Epidemiology, treatment, and guidelines for the treatment of heart failure in Europe. European Heart Journal Supplements, 7, 5–9.

[3] Murphy, T. M., et al. (2017). A comparison of HFrEF vs HFpEF’s clinical workload and cost in the first year following hospitalization and enrollment in a disease management program. International Journal of Cardiology, 232, 330–335.

[4] Krumholz, H. M., et al. (2009). Patterns of Hospital Performance in Acute Myocardial Infarction and Heart Failure 30-Day Mortality and Readmission. Circulation: Cardiovascular Quality and Outcomes, 2(5), 407–413.

[5] Oktay, A. A., Rich, J.D. and Shah, S.J. (2013). The Emerging Epidemic of Heart Failure with Preserved Ejection Fraction. Current Heart Failure Reports, 10(4), 401–410.

[6] Oktay, A .A., Rich, J.D. and Shah, S.J. (2013). The Emerging Epidemic of Heart Failure with Preserved Ejection Fraction. Current Heart Failure Reports, 10(4), 401–410.

[7] Nagueh, S. F., et al. (2016). Recommendations for the Evaluation of Left Ventricular Diastolic Function by Echocardiography: An Update from the American Society of Echocardiography and the European Association of Cardiovascular Imaging. Journal of the American Society of Echocardiography, 29(4), 277–314.

[8] Tanter, M. and Fink, M. (2014). Ultrafast imaging in biomedical ultrasound. IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control, 61(1), 102–119.

[9] Cikes, M., Tong, L., Sutherland, G.R. and D’hooge, J. (2014). Ultrafast Cardiac Ultrasound Imaging. JACC: Cardiovascular Imaging, 7(8), 812–823.

[10] Kanai, H. (2005). Propagation of spontaneously actuated pulsive vibration in human heart wall and in vivo viscoelasticity estimation. IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control, 52(11), 1931–1942.