Impact of Age and Heart Rate on Strain-Derived Myocardial Work in a Population of Healthy Subjects

Figures

• 

  Figure 1. Methodology for measuring strain-derived myocardial work. In the left side the strain pressure loop: the area inside the loop corresponds to global work index (panel A). In the right panel Doppler-derived measurement needed to mark systolic and diastolic time intervals (panel B). AVC = Aortic valve closure, AVO = Aortic valve opening, LVP = Left ventricular pressure, MVC = Mitral valve closure, MVO = Mitral valve opening.

• 

  Figure 2. The strain-derived MW analysis of two healthy subjects with similar age, the first with sinus bradycardia and the second one with HR = 88 bpm: GWW is substantially higher in the subjects with faster HR. Strain-Pressure (LVP) loop (upper left panel of each figure), regional myocardial efficiency bull’s eye (upper right panel), diagram of average constructive and wasted work percentages (lower left panel) and list of global work components (lower right panel) in a 57-year-old healthy female subject with sinus bradycardia (HR = 56 bpm) (A) and in a 58-year-old healthy male subject with HR = 88 bpm (B). In presence of marginal changes of the global constructive work, the percentage of global wasted work is relatively low in the patient with sinus bradycardia (A) whereas it appears to be substantially increased in the patient with HR = 88 bpm (B). GCW = Global constructive work, GWE = Global work efficiency, GWW = Global wasted work, GWI = Global work index.