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Aims Myocardial work (MW) is a novel parameter that can be used in a clinical setting to assess left ventricular (LV) pressures and deformation. We sought to distinguish patterns of global MW index in hypertensive vs. non-hypertensive patients and to look at differences between categories of hypertension. Methods and results Sixty-five hypertensive patients (mean age 65 ± 13 years; 30 male) and 15 controls (mean age 38 ± 12 years; 7 male) underwent transthoracic echocardiography at rest. Hypertensive patients were subdivided into Stage 1 (n = 32) and Stage 2 (n = 33) hypertension based on 2017 American College of Cardiology guidelines. Exclusion criteria were suboptimal image quality for myocardial deformation analysis, reduced ejection fraction, valvular heart disease, intracardiac shunt, and arrhythmia. Global work index (GWI), global constructive work (GCW), global wasted work (GWW), and global work efficiency were estimated from LV pressure–strain loops utilizing proprietary software from speckle-tracking echocardiography. LV systolic and diastolic pressures were estimated using non-invasive brachial artery cuff pressure. Global longitudinal strain and LV ejection fraction were preserved between the groups with no statistically significant difference, whereas there was a statically significant difference between the control and two hypertension groups in GWI (P = 0.01), GCW (P < 0.001), and GWW (P < 0.001). Conclusion Non-invasive MW analysis allows better understanding of LV response under conditions of increased afterload. MW is an advanced assessment of LV systolic function in hypertension patients, giving a closer look at the relationship between LV pressure and contractility in settings of increased load dependency than LV ejection fraction and global longitudinal strain.

Highlights Prone positioning improves oxygenation in patients with ARDS. Reducing RV dysfunction is vital as reduced RVLS is associated with increased mortality. Prone positioning may assist cardiac function by offloading pressure from the RV.

A 57-year-old man with no medical history presented to an outside hospital with the chief complaint of shortness of breath and cough. The patient tested positive for coronavirus disease 2019 (COVID-19). He presented to our institution 1 day later, and work-up included a chest X-ray that revealed patchy opacities in the bilateral mid to lower lung fields (Panel A) consistent with the recent diagnosis of COVID-19. He underwent transthoracic echocardiography to assess for COVID-19-related myocardial dysfunction. He was in normal sinus rhythm, and cuff blood pressure (BP) at the time of examination was 106/76 mmHg. Left ventricular ejection fraction (LVEF) was normal at 62% (Supplementary material online, Video S1), global longitudinal strain (GLS) was at the lower limits of normal at-18% (Panel B), global work index (GWI) was significantly reduced at 727 mmHg% (Panel C), and global work efficiency (GWE) was 95% (Panel D). The patient was discharged home and was symptom free at the 1-month follow-up. Cuff BP was 133/90 mmHg, and repeat echocardiography demonstrated a stable LVEF (Supplementary material online, Video S2), GLS (Panel E), and a significantly improved GWI of 1669 mmHg% (Panel F). GWE also remained relatively unchanged (Panel G). A difference in systolic BP of 27 mmHg between the two examinations is not enough to account for the drastic improvement in GWI. With no known underlying comorbidities contributing to the reduced GWI, we can hypothesize that myocardial work sets the stage as an even earlier indicator of COVID-19-induced myocardial dysfunction than reduced GLS and LVEF.

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