star goldstar goldstar goldstar goldstar greyFemaleMale
36 Questions - Developed by: V - Developed on: - 1.120 taken

  • 1
    - an action potential (membrane potential) of myocardial cell is identical with ECG curve
  • 2
    - the wave P on ECG curve represents a repolarization of heart atria
  • 3
    - an electrocardiography is a record of mechanical changes during the heart cycle
  • 4
    - bipolar leads detect a potential difference between two inert (neutral) electrodes
  • 5
    - the duration of myocardial action potential is typically over 200 ms
  • 6
    - during the phase of depolarization the myocardial muscle fiber behaves as an electrical
  • 7
    - the depolarization of both heart ventricles is manifested on ECG curve as the QRS complex
  • 8
    - the repolarization of ventricles on the ECG curve represents PQ interval
  • 9
    - the wave T on ECG curve represents the repolarization of conductive system of the heart
  • 10
    - in order to determine an electrical axis of the heart one can use the amplitudes of deflections from the standard limb leads
  • 11
    - electrical potentials from the body surface are recorded by pin (needle) electrodes
  • 12
    - using the bipolar leads (e.g. CR, CL, CF) the potential difference between two places on the body surface is measured
  • 13
    - an isoelectric line represents the level of constant but not zero (neutral) potential
  • 14
    - a monophasic potential is obtained by bipolar electrodes
  • 15
    - during the ECG recording the examined person must be grounded
  • 16
    - the standard bipolar limb leads are labeled as I., II., III.
  • 17
    - a bipolar limb lead I. detects the potential difference between the right hand and left foot
  • 18
    - a bipolar limb lead III. detects the potential difference between the right and left foot
  • 19
    - one can determine the heart rate (the frequency of the heart beating) from the time difference R-R (a period of ECG cycle)
  • 20
    - the electrical axis of the heart is determined from at least two bipolar leads of ECG
  • 21
    - normal duration of PQ interval may exceed 0.22 s
  • 22
    - the time duration of PQ segment is approx. a half of PQ interval
  • 23
    - a normal duration of QRS complex is 0.08 ms
  • 24
    - normal duration of ST segment is above 0.22 s
  • 25
    - the interval QT is one of the most variable characteristics of ECG curve, it shortens at
    a higher heart rate
  • 26
    - the duration of P wave on the ECG curve is typically longer than the duration of wave T
  • 27
    - the complex QRS on the ECG curve consists of oscillations Q and S and the isoelectric
    segment R
  • 28
    - on the ECG curve the deflections P and T from an isolelectric line are denoted as waves
  • 29
    - the segments PQ and ST represent an isoelectric line (they have zero electric potential)
  • 30
    - the intervals PQ and ST represent an isoelectric line
  • 31
    - the augmented unipolar limb leads are designated as VR, VL, and VF
  • 32
    - the Wilson clamp represents a „star“ connection of three 5000 ohm resistors, by which the electrodes are connected to the right hand, left hand, and left foot
  • 33
    - the unipolar chest leads (labeled as V1, V2, up to V6) detect the potential difference by the set of electrodes placed on the chest
  • 34
    - during the construction of the heart electrical axis one may put the final values of QRS vectors at vertexes of equilateral triangle
  • 35
    - an electrical axis of the heart represents the vector oriented from the upper left side of the thorax downward to the left
  • 36
    - physiological (normal) direction of the heart electrical axis in a frontal plane is from +30 to +120˚ from the horizontal direction to the left and clockwise

Comments (0)