ABSTRACT
Introduction: Transthoracic Echocardiography (TTE) is an essential tool in the diagnosis and treatment of Heart Failure (HF). Miniaturisation of Echocardiography with the use of handheld Echo (HHE) devices has raised new possibilities regarding the point-of-care applicability of this modality. These devices have mainly been equipped with 2D and colour Doppler modalities and their use for predicting left ventricular size and function can aid significantly in the management of HF. Their efficiency makes them especially valuable in settings where there is restricted access to hospital-based imaging either due to geography (remote locations) or due to safety concerns (like the recent COVID19 restrictions). Background: There have been limited number of studies assessing the usefulness and reliability of HHE in the outpatient setting and the results have been conflicting. One study in 2011 reported that HHE missed no relevant findings [1], whereas another study in 2014 demonstrated discordant findings up to 27% of patients when comparing HHE to standard TTE [2]. The goal of our study is to provide further evidence with real-life data that HHE can be a reliable tool in providing prompt treatment in HF patients while also understanding its limitations. Method: We included in the study 100 patients seen in our rapid access HF clinic (between February and June 2021) that had HHE (performed by a Heart Failure consultant) during their consultation and then underwent follow up cardiac structure imaging (either by standard TTE (n=75) or cardiac MRI (n=25)). The parameters included 1) assessment of LV systolic function, 2) degree of mitral regurgitation, 3) aortic valve assessment. The clinic HHE findings were based on the dictated clinic letters, whereas the formal TTE/MRI reports were sourced through our online database. The classification of LV systolic function and valve function was based on the most recent BSEcho guidelines. Results: HHE was accurate in detecting LV systolic impairment when compared with the findings of standard TTE or MRI (Sensitivity 91%, specificity 86%, positive predictive value 86%, negative predictive value 92%). For severe LV systolic impairment, the sensitivity was 94% and specificity 89% (PPV=64%, NPV=98%). For identification of severe aortic valve disease, the results were consistent (sensitivity 80%, specificity 98%, PPV 80%, NPV 98%). Detection of severe mitral valve regurgitation was less reliable (sensitivity 42%, specificity 96%, PPV 50%, NPV 95%) as expected by the complex nature of its Echocardiographic diagnosis. Conclusion: The above results support the routine use of HHE in HF clinics to expedite treatment and improve patient outcomes, especially in patients with severe LV systolic impairment. At the same time, HHE should not be relied upon to provide a final verdict in structural heart disease assessment, but is should be accompanied by a formal imaging modality like standard TTE or cardiac MRI.