Atrial fibrillation: the story begins with the left atrium.
After half a dozen guidelines from the ACC, AHA, and ESC, the latest one for the first time ever recommends rhythm control as a first line management strategy either by ablation or by antiarrythmic drugs4. The document also elegantly presents criteria for selection of patients most suitable for ablation. Among others the size of the left atrium is the key. However, the size or the volume of the left atrium may not matter more than its mechanical integrity5. Kuppahally, et al 6 have shown the left atrial strain is a surrogate for fibrosis and the degree of fibrosis, and consequently magnitude of reservoir strain, depends on whether the AF is paroxysmal (less fibrosis, better strain) or persistent (more the fibrosis, worse is the strain). A just published paper has shown that an increased glucose (FDG-PET) metabolism in LA results in decreased LA strain: after successful ablation and restoration of sinus rhythm, the uptake of glucose decreases, and the longitudinal strain increases that coincides with decreased LA volume7. To negotiate the hydraulic and mechanical properties of the LA, the new AFI software provides biplane LA volume and all the three components of reservoir, conduit, and booster strain in no time (Figure 1). The AFI software in fact utilizes machine learning algorithms to automate LA volume and strain measurements, thereby significantly streamlining the process. We expect that in the not- too- distant future, cardiologists and electrophysiologists will utilize the ultra-modern SW for superfast assessment of LA size and strain at one go before considering ablation in eligible subjects.