Figure Legends
Figure 1a-h. Example of TTE and CMR Images. TTE images in the 4-chamber
(A) and mid-ventricular short axis (B) with suboptimal images due to
poor acoustic windows. CMR LGE images in the 4-chamber (C) and short
axis (D) with LGE (bright areas delineated by red arrows) in the same
patients at later stage of DMD-CM. Cine Images in the 4-chamber (E) and
short axis (F) with good quality images by CMR despite poor TTE acoustic
windows. Tagged images for myocardial strain in the 4-chamber (G) and
short axis (H).
Figure 2. Scatter Plot of DMD Patients by Age and LVEF. LVEF abnormality
(define as <55% delineated by red dotted horizontal line) is
uncommon before age 10 years (highlighted transparent red rectangular
box) and incidence increases with age.
Figure 3. Plot of Percentage of DMD Patients with LVEF <55%
by Age. The percent of DMD patients with LVEF below 55% is uncommon
before 10 years of age and increased with Age.
Figure 4. Plot of Percentage of DMD Patients with LGE by Age. The
percent of DMD patients with LGE increased with age and starts as early
as 7 years.
Figure 5. Concept of Myocardial Strain. Displacement and Velocity
measures motion as the heart empties and fill. Myocardial strain
analysis detects myocardial contractility. Positive strain is stretching
of the myocardium (radial direction visualized as thickening of the
myocardium, yellow oval and increased thickness of the rectangle).
Negative strain is contraction of the myocardium (can occur in the
longitudinal along the long axis of the heart or circumferential in the
oblique axis of the heart, red oval) follows the direction of the
myocardial fiber.
Figure 6a-h. LGE Pattern in DMD is Unique. Normal myocardium remain dark
after giving contrast agent as shown in 4-chamber (A) and short axis
(B). In patients with heart attack or myocardial infarction the area
that is injured or has scar remains bright and is typically in the
subendocardial region (inner part of the muscle) encircled by the dashed
red lines and delineated by the white areas from the base to the apical
sections of the heart (C-D respectively). Similarly the fibrosis in DMD
is white after contrast as encircled by pink dashed and highlighted by
pink arrows and in contrast it is in the outer surface of the heart or
subepicardium (F-H).
Figure 7a-h. LGE Burden Increased with Age. Normal subject with no LGE
(all black delineated by yellow arrows) in the 4-chamber (A) and short
axis (B). Young DMD patient with small area of LGE (bright area
delineated by red arrows) in 4-chamber (C) and short mid-ventricular
short axis (D). Older DMD patient with increased LGE (bright area
delineated by red arrows) with preserved LVEF in 4-chamber (E) and short
mid-ventricular short axis (F). Older DMD patient with late stage DMD-CM
with dilated chamber and extensive LGE involving nearly full thickness
of the myocardium in multiple segments including the septum (bright area
delineated by red arrows) in 4-chamber (G) and short mid-ventricular
short axis (H).
Figure 8a-l. LGE and T1 Mapping by CMR. T1 is abnormal in DMD and
increased with age. Normal patient with no LGE (no bright areas, yellow
arrows) in the 4-chamber (B), short axis (A) and normal T1 of 1155
millisecond. Young DMD patient with no LGE in the 4-chamber (B), short
axis (A) and with slightly increased T1 of 1180 millisecond. Younger DMD
patient with LGE (bright areas delineated by red arrows) in the
4-chamber (B), short axis (A) and with elevated increased T1 of 1230
millisecond. Older DMD patient with extensive LGE including the septum
(bright areas delineated by red arrows) in the 4-chamber (B), short axis
(A) and with very elevated increased T1 of 1355 millisecond.
Figure 9. Case Example of Progressive DMD-CM. Patient followed at age 5
years with yearly with normal LVEF (blue arrow) with no cardiac therapy.
LVEF declined to 48% at age 14 years (yellow arrow) and despite
escalation of care LVEF continued to decline including milrinone
infusion (red arrows) resulting in placement of a left ventricular
assist device with continued severe LV dysfunction (red arrows) and now
right ventricular dysfunction.