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.