°/s	degrees per second
1D	one-dimensional
3D	three-dimensional
AC	Aortic valve closure
ADA	Autocorrelated Differential Algorithm
AFib	Atrial fibrillation
ANN	Artificial Neural Network
AO	Aortic valve opening
AVNN	mean inter-beat interval
BCG	ballistocardiography
BMI	Body Mass Index
BPM	Beats per minute
CAD	Coronary artery disease
CNN	Convolutional neural network
CWT	Continuous Wavelet Transform
CT	Computed Tomography
dps	degrees per second
DPV	Diastolic peak velocity
Ea	Early diastolic velocity
ECG	Electrocardiography
EMD	Empirical Mode Decomposition
FHR	Fetal Heart Rate
GCG	Gyrocardiography
HABIT	Hilbert adaptive beat identification technique
HF	the power of the HRV spectrum in the high frequency range
HR	Heart rate
HRV	Heart rate variability
ICA	Independent Component Analysis
IMU	Inertial Measurement Unit
IVCT	Isovolumetric contraction time
IVRT	Isovolumetric relaxation time
KSVM	Kernel Support Vector Machine
LBP	Local Binary Patterns
LOOCV	Leave-one-out Cross-Validation
LF	the power of the HRV spectrum in the low frequency range
LF/HF	LF/HF power ratio
LR	Logistic regression
LV	Left ventricular
LVET	Left Ventricular Ejection Time
MC	Mitral valve closures
MCG	Mechanocardiography
MEMS	Microelectromechanical systems
MO	Mitral valve opening
MRI	Magnetic Resonance Imaging
NN50	number of successive RR intervals differing more than 50 ms
PCG	Phonocardiogram
PEP	Pre-ejection Period
PET	Positron Emission Tomography
pNN50	probability of NN50 against total number of inter-beat intervals
PWD	Pulse Wave Doppler
QS2	Total electromechanical systole
RF	Random Forest
RKE	Rotational Kinetic Energy
RMSSD	Root mean square of successive differences between inter-beat intervals
Sa	Systolic myocardial velocity
SCG	Seismocardiography
SD	Standard deviation
SDNN	Standard deviation of the inter-beat interval
SFFT	Sparse Fast Fourier Transform
SMQT	successive mean quantization transform
SPV	Systolic peak velocity
STI	Systolic time interval
SVM	Support Vector Machine
TAVR	Transcatheter aortic valve replacement
TDI	Tissue Doppler Imaging
TIMM	Baseline width of the RR interval histogram
VLF	the power of the HRV spectrum in the very low frequency range
XGB	Extreme Gradient Boosting