MIT-BIH

MIT-BIH Arrhythmia Database

Clinical & physiological

The classic reference standard for arrhythmia detection research: 48 half-hour excerpts of two-channel ambulatory ECG recordings, with beat-by-beat annotations by expert cardiologists.

MIT / Beth Israel — PhysioNetOfficial source

Signal specification fields

Each signal (channel) in a WFDB record is described by the following header fields. Optional fields may be absent depending on the record.

Field	Required	Description
File name	Required	Name of the signal (.dat) file this channel is stored in.
Format	Required	Storage format code for the samples (e.g. 212).
Samples per frame	Optional	Samples of this signal per frame (for multi-frequency records).
Skew	Optional	Number of samples this signal is skewed relative to others.
Byte offset	Optional	Byte offset of sample data within the signal file.
ADC gain	Optional	ADC units per physical unit (e.g. per mV).
Baseline	Optional	ADC value corresponding to 0 physical units.
Units	Optional	Physical units of the signal (e.g. mV).
ADC resolution	Optional	ADC resolution in bits.
ADC zero	Optional	ADC output for zero input (midrange ADC value).
Initial value	Optional	First sample value of the signal.
Checksum	Optional	16-bit checksum of all samples (integrity check).
Block size	Optional	Block size for reading the signal file (0 = unbuffered).
Description	Optional	Free-text label / lead name for the signal (e.g. MLII, V5).

Example record

#100

A worked example showing the values for one MIT-BIH record.

Record ID

100

Sampling rate

360 Hz

Samples

650,000

Duration

1,805.56 s

Signals

Signals (2)

Description	File name	Format	ADC gain	Baseline	ADC resolution	ADC zero	Initial value	Block size
MLII	100.dat	212	200	1024	11	995	-22131	0
V5	100.dat	212	200	1024	11	1011	20052	0

Patient

Age69

SexMale

MedicationsAldometInderal

Comments1085 1629 x1

Beat annotations2,274 beats

eAtrial escape beat1

NNormal beat2,239

AAtrial premature beat33

VPremature ventricular contraction1

Rhythm: (N at sample 18