Table of Contents

12-lead electrocardiogram

Resting ECGs (section: physical state) were taken in Lifelines participants aged 13 years and older during:

Background

The 12-lead resting ECG measures electrical activity of the heart during rest, summarized in 12 leads.
The ECG provides many (>400) different variables at once, both quantitative and qualitative traits. These include duration, voltage and configuration characteristics. For example, information is provided of the cardiac rhythm, heart rate, the function of the sinoatrial and the atrioventricular node, atrial size, left ventricular mass, and repolarisation time (e.g. QT time).

Device

Welch Allyn CardioPerfekt Workstation ecg_manual.pdf
Welch Allyn CardioPerfect Workstation Software ecg_software_manual.pdf
DT100 vacuum units (suction electrode system).

Protocol

Electrodes were placed with conduction spray on ten clean spots at the abdomen and left side of the chest of lying participants (see illustration). In case of dextrocardia, the electrodes were mirrored.

All ECGs were checked by the research nurse and the Welch Allyn algorithm using CardioPerfekt software (see flow chart). ECG deviations (atrium fibrillation, atrium flutter, bradycardia, tachycardia, infoaction, acute ischemia, ST elevation, Wolff Parkinson White Syndrome, bigemenia, Left Bundle Branch Block, >1 premature ventricular contraction, second or third grade AV-block, pacemaker) were reported to a cardiologist.

Variables

The ECG resulted in the following variables:

English Variable Code Assessment Age
ecg performed ecgond_1 ecg_performed_all_m_1 1A 13+
ecg performed ecgond_2 ecg_performed_all_m_2 2A 3A 13+
if not, reason: / ecg performed ecg_reden ecg_performed_all_m_2_a 2A 3A 13+
ecg device code ecgdevice ecg_devicecode_all_m_1 2A 13+
is ecg to be manually reviewed by a doctor? review ecg_toreview_all_e_1 1A 2A 13+
research nurse - ecg result needs to be reviewed by ecg assistant needs_review_ecg ecg_toreview_all_e_2 3A 13+
is the ecg manually reviewed by a doctor? reviewed ecg_reviewed_all_e_1 1A 2A 13+
system evaluation ecg systeem ecg_system_all_m_1 3A 13+
automatic interpretation by welch allyn means ecg_welchallyn_all_m_1 1A 2A 13+
ecg technician - category of ECG review ecg_functieanalist_ecg_category ecg_category_all_e_1 3A 13+
ecg technician - advise to GP based on ecg review ecg_functieanalist_ecg_feedback_gp ecg_gpadvise_all_e_1 3A 13+
ecg technician - technical review ecg_functieanalist_ecg_conclusion ecg_technicalquality_all_e_1 3A 13+
heart rate hr ecg_heartrate_all_m_1 1A 2A 13+
overall p-axis (degrees) p_axis p_axis_all_m_1 1A 2A 3A 13+
overall duration of p-wave (ms) p p_wave_all_m_1 1A 2A 3A 13+
overall pq time (ms) pq pq_time_all_m_1 1A 2A 3A 13+
overall qrs-axis (degrees) qrs_axis qrs_axis_all_m_1 1A 2A 3A 13+
qt-interval (ms) qt qt_interval_all_m_1 1A 2A 3A 13+
overall duration of the qrs-complex (ms) qrs qrs_complex_all_m_1 1A 2A 3A 13+
qt-interval (ms) corrected for heart frequency (hodges) qtc qtc_interval_all_m_1 1A 2A 3A 13+
overall t-axis (degrees) t_axis t_axis_all_m_1 1A 2A 3A 13+
negative amplitude of p-wave (microvolt) - lead I - II - III - aVR - aVL - aVF / V1 - V2 - V3 - V4 - V5 - V6 pnegamp_1-6/15-20 pnegamp_i/ii/iii/avr/avl/avf/v1-6_all_m_1 1A 2A 3A 13+
posittive amplitude of p-wave (microvolt) - lead I - II - III - aVR - aVL - aVF / V1 - V2 - V3 - V4 - V5 - V6 pposamp_1-6/15-20 pposamp_i/ii/iii/avr/avl/avf/v1-6_all_m_1 1A 2A 3A 13+
amplitude of the q-wave (microvolt) - lead I - II - III - aVR - aVL - aVF / V1 - V2 - V3 - V4 - V5 - V6 qamp_1-6/15-20 qamp_i/ii/iii/avr/avl/avf/v1-6_all_m_1 1A 2A 3A 13+
duration of the q-wave (ms) - lead I - II - III - aVR - aVL - aVF / V1 - V2 - V3 - V4 - V5 - V6 qduration_1-6/15-20 qduration_i/ii/iii/avr/avl/avf/v1-6_all_m_1 1A 2A 3A 13+
amplitude of the r'-wave (microvolt) - lead I - II - III - aVR - aVL - aVF / V1 - V2 - V3 - V4 - V5 - V6 raccamp_1-6/15-20 raccamp_i/ii/iii/avr/avl/avf/v1-6_all_m_1 1A 2A 3A 13+
duration of the r'-wave (ms) - lead I - II - III - aVR - aVL - aVF / V1 - V2 - V3 - V4 - V5 - V6 raccduration_1-6/15-20 raccduration_i/ii/iii/avr/avl/avf/v1-6_all_m_1 1A 2A 3A 13+
amplitude of the r-wave (microvolt) - lead I - II - III - aVR - aVL - aVF / V1 - V2 - V3 - V4 - V5 - V6 ramp_1-6/15-20 ramp_i/ii/iii/avr/avl/avf/v1-6_all_m_1 1A 2A 3A 13+
duration of the r-wave (ms) - lead I - II - III - aVR - aVL - aVF / V1 - V2 - V3 - V4 - V5 - V6 rduration_1-6/15-20 rduration_i/ii/iii/avr/avl/avf/v1-6_all_m_1 1A 2A 3A 13+
amplitude of the s'-wave (microvolt) - lead I - II - III - aVR - aVL - aVF / V1 - V2 - V3 - V4 - V5 - V6 saccamp_1-6/15-20 saccamp_i/ii/iii/avr/avl/avf/v1-6_all_m_1 1A 2A 3A 13+
duration of the s'-wave (ms) - lead I - II - III - aVR - aVL - aVF / V1 - V2 - V3 - V4 - V5 - V6 saccduration_1-6/15-20 saccduration_i/ii/iii/avr/avl/avf/v1-6_all_m_1 1A 2A 3A 13+
amplitude of the s-wave (microvolt) - lead I - II - III - aVR - aVL - aVF / V1 - V2 - V3 - V4 - V5 - V6 samp_1-6/15-20 samp_i/ii/iii/avr/avl/avf/v1-6_all_m_1 1A 2A 3A 13+
duration of the s-wave (ms) - lead I - II - III - aVR - aVL - aVF / V1 - V2 - V3 - V4 - V5 - V6 sduration_1-6/15-20 sduration_i/ii/iii/avr/avl/avf/v1-6_all_m_1 1A 2A 3A 13+
deviation from the st segment at 0 ms from the j point (mm) - lead I - II - III - aVR - aVL - aVF / V1 - V2 - V3 - V4 - V5 - V6 st0_1-6/15-20 st0_i/ii/iii/avr/avl/avf/v1-6_all_m_1 1A 2A 3A 13+
deviation from the st segment at 20 ms from the j point (mm) - lead I - II - III - aVR - aVL - aVF / V1 - V2 - V3 - V4 - V5 - V6 st20_1-6/15-20 st20_i/ii/iii/avr/avl/avf/v1-6_all_m_1 1A 2A 3A 13+
deviation from the st segment at 40 ms from the j point (mm) - lead I - II - III - aVR - aVL - aVF / V1 - V2 - V3 - V4 - V5 - V6 st40_1-6/15-20 st40_i/ii/iii/avr/avl/avf/v1-6_all_m_1 1A 2A 3A 13+
deviation from the st segment at 60 ms from the j point (mm) - lead I - II - III - aVR - aVL - aVF / V1 - V2 - V3 - V4 - V5 - V6 st60_1-6/15-20 st60_i/ii/iii/avr/avl/avf/v1-6_all_m_1 1A 2A 3A 13+
deviation from the st segment at 80 ms from the j point (mm) - lead I - II - III - aVR - aVL - aVF / V1 - V2 - V3 - V4 - V5 - V6 st80_1-6/15-20 st80_i/ii/iii/avr/avl/avf/v1-6_all_m_1 1A 2A 3A 13+
negative amplitude of t-wave (microvolt) - lead I - II - III - aVR - aVL - aVF / V1 - V2 - V3 - V4 - V5 - V6 tnegamp_1-6/15-20 tnegamp_i/ii/iii/avr/avl/avf/v1-6_all_m_1 1A 2A 3A 13+
positive amplitude of t-wave (microvolt) - lead I - II - III - aVR - aVL - aVF / V1 - V2 - V3 - V4 - V5 - V6 tposamp_1-6/15-20 tposamp_i/ii/iii/avr/avl/avf/v1-6_all_m_1 1A 2A 3A 13+
negative amplitude of p-wave (microvolt) - lead X - Y - Z pnegamp_23-25 pnegamp_x/y/z_all_m_1 2A 3A 13+
posittive amplitude of p-wave (microvolt) - lead X - Y - Z pposamp_23-25 pposamp_x/y/z_all_m_1 2A 3A 13+
amplitude of the q-wave (microvolt) - lead X - Y - Z qamp_23-25 qamp_x/y/z_all_m_1 2A 3A 13+
duration of the q-wave (ms) - lead X - Y - Z qduration_23-25 qduration_x/y/z_all_m_1 2A 3A 13+
amplitude of the r'-wave (microvolt) - lead X - Y - Z raccamp_23-25 raccamp_x/y/z_all_m_1 2A 3A 13+
duration of the r'-wave (ms) - lead X - Y - Z raccduration_23-25 raccduration_x/y/z_all_m_1 2A 3A 13+
amplitude of the r-wave (microvolt) - lead X - Y - Z ramp_23-25 ramp_x/y/z_all_m_1 2A 3A 13+
duration of the r-wave (ms) - lead X - Y - Z rduration_23-25 rduration_x/y/z_all_m_1 2A 3A 13+
amplitude of the s'-wave (microvolt) - lead X - Y - Z saccamp_23-25 saccamp_x/y/z_all_m_1 2A 3A 13+
duration of the s'-wave (ms) - lead X - Y - Z saccduration_23-25 saccduration_x/y/z_all_m_1 2A 3A 13+
amplitude of the s-wave (microvolt) - lead X - Y - Z samp_23-25 samp_x/y/z_all_m_1 2A 3A 13+
duration of the s-wave (ms) - lead X - Y - Z sduration_23-25 sduration_x/y/z_all_m_1 2A 3A 13+
deviation from the st segment at 0 ms from the j point (mm) - lead X - Y - Z st0_23-25 st0_x/y/z_all_m_1 2A 3A 13+
deviation from the st segment at 20 ms from the j point (mm) - lead X - Y - Z st20_23-25 st20_x/y/z_all_m_1 2A 3A 13+
deviation from the st segment at 40 ms from the j point (mm) - lead X - Y - Z st40_23-25 st40_x/y/z_all_m_1 2A 3A 13+
deviation from the st segment at 60 ms from the j point (mm) - lead X - Y - Z st60_23-25 st60_x/y/z_all_m_1 2A 3A 13+
deviation from the st segment at 80 ms from the j point (mm) - lead X - Y - Z st80_23-25 st80_x/y/z_all_m_1 2A 3A 13+
negative amplitude of t-wave (microvolt) - lead X - Y - Z tnegamp_23-25 tnegamp_x/y/z_all_m_1 2A 3A 13+
posittive amplitude of t-wave (microvolt) - lead X - Y - Z tposamp_23-25 tposamp_x/y/z_all_m_1 2A 3A 13+