# SRElectrocardiogramSample The sample electrocardiogram sensor data. ``` class SRElectrocardiogramSample ``` ## Overview The electrocardiogram (ECG) sensor provides an array of these objects as its [`sample`](/documentation/SensorKit/SRFetchResult/sample) type. ## Topics ### Accessing ECG data [`var date: Date`](/documentation/SensorKit/SRElectrocardiogramSample/date) The start date of the ECG sensor data recording, not the start of the session. [`var frequency: Measurement`](/documentation/SensorKit/SRElectrocardiogramSample/frequency) The frequency in hertz that the ECG sensor records the data. [`var lead: SRElectrocardiogramSample.Lead`](/documentation/SensorKit/SRElectrocardiogramSample/lead-swift.property) The lead used to record the ECG data. [`enum Lead`](/documentation/SensorKit/SRElectrocardiogramSample/Lead-swift.enum) The location of the lead that a person uses to record the ECG data. [`var session: SRElectrocardiogramSession`](/documentation/SensorKit/SRElectrocardiogramSample/session) The session where this sample occurs. [`class SRElectrocardiogramSession`](/documentation/SensorKit/SRElectrocardiogramSession) An object that represents ECG data that a device records during a period of time. [`var data: [SRElectrocardiogramData]`](/documentation/SensorKit/SRElectrocardiogramSample/data) The data that the sensor records. [`class SRElectrocardiogramData`](/documentation/SensorKit/SRElectrocardiogramData) A representation of the ECG data that the sensor records. ## Relationships ### Conforms To [`Hashable`](/documentation/Swift/Hashable) [`CustomDebugStringConvertible`](/documentation/Swift/CustomDebugStringConvertible) [`Sendable`](/documentation/Swift/Sendable) [`NSCoding`](/documentation/Foundation/NSCoding) [`Equatable`](/documentation/Swift/Equatable) [`CustomStringConvertible`](/documentation/Swift/CustomStringConvertible) [`SendableMetatype`](/documentation/Swift/SendableMetatype) [`NSCopying`](/documentation/Foundation/NSCopying) [`CVarArg`](/documentation/Swift/CVarArg) [`NSObjectProtocol`](/documentation/ObjectiveC/NSObjectProtocol) [`NSSecureCoding`](/documentation/Foundation/NSSecureCoding) ### Inherits From [`NSObject-swift.class`](/documentation/ObjectiveC/NSObject-swift.class) --- Copyright © 2026 Apple Inc. All rights reserved. | [Terms of Use](https://www.apple.com/legal/internet-services/terms/site.html) | [Privacy Policy](https://www.apple.com/privacy/privacy-policy)