2D	2-dimensional
2D-STE	2-dimensional speckle tracking echocardiography
A	late diastolic mitral inflow velocity
E	early diastolic mitral inflow velocity
e′	early diastolic tissue Doppler velocity
E/A	ratio of early to late diastolic mitral inflow velocities
GCS	global circumferential strain
GCSRe	global circumferential early diastolic strain rate
GLS	global longitudinal strain
GLSRe	global longitudinal early diastolic strain rate
GLSRs	global longitudinal systolic strain rate
GRS	global radial strain
GRSRe	global radial early diastolic strain rate
LV	left ventricular
LVEF	left ventricular ejection fraction
PBT	proton beam therapy
PhT	photon beam therapy
RT	radiotherapy
RV	right ventricular
S′	systolic annular tissue velocity
SRe	early diastolic strain rate
SRs	systolic strain rate
TAPSE	tricuspid annular plane systolic excursion
TTE	transthoracic echocardiography