A heart rate monitor provides a pulse or heartbeat, but without the on-going or continuous phase signal of ECG and/or with a delay relative to the actual heartbeat. For phase determination in echocardiography, the heartbeat from the heart rate monitor is used to assist in identification of phase from acquired ultrasound data. Rather than relying on just ECG or just image processing, the worn or handheld heart rate monitor is used to simplify the image process-based identification of phase.
