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					                                    14874a99-c5a5-42ca-bb69-939522cb4cff.xls

  Purpose: To determine the electrical axis in the                                Citations with   Sriram & Svirbely 1999
   frontal plane for the QRS complex from the                                     documentatio
               standard limb leads.                                                n. 07.16.01


data                                                  enter
Do you want to determine the frontal electrical
        axis for the QRS? (Y or N)                              y :-):-):-)

   enter an "x" in the appropriate column for each standard limb lead
            indicating the wave form (only 1 answer per row)
                                                     negative        isolectric     positive
                                              I                                                       No      check data
                                                     negative        isolectric     positive
                                             II                                                       No      check data
                                                     negative        isolectric     positive
                                             III                                                      No      check data
                                                     negative        isolectric     positive
                                          aVL                                                         No      check data
                                                     negative        isolectric     positive
                                          aVF                                                         No      check data
                                                     negative        isolectric     positive
                                         aVR                                                          No      check data


calculate                                result
data complete?                                  No
evaluation appropriate?              complete data :-):-):-)
QRS electrical axis in frontal plane               complete data
          which indicates the the axis             complete data


                                            0      check data check data                                       #N/A
                                          113                    shows to +239°)
                                                   -121° to -149° (+211extreme axis deviation
                                          123      -120° (+240°)shows extreme axis deviation
                                          133                    shows extreme
                                                   -91° to -119° (+241 to +269°) axis deviation
                                          143      -150° (+210°)shows extreme axis deviation
                                          163                    shows to +209°)
                                                   -151° to -179° (+181extreme axis deviation
                                          165      -180° (+180°)shows right axis deviation
                                          168                    s
                                                   +151 to +179° hows right axis deviation
                                          268      +150°         shows right axis deviation
                                          366      +91 to +119° shows right axis deviation
                                          367      +120°         shows right axis deviation
                                          368                    s
                                                   +121 to +149° hows right axis deviation
                                          433      -90° (+270°) shows left axis deviation
                                          566      +90°          is borderline normal (vs right axis deviation)
                                          631      -31° to -59° shows left axis deviation
                                          632      -60°          shows left axis deviation
                                          633      -61 to -89° shows left axis deviation
                                          731      -30°          is borderline normal (vs left axis deviation)
                                          831      -1° to -29° is normal
                                          834      0°            is normal
                                          836      +1 to +29° is normal


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                             14874a99-c5a5-42ca-bb69-939522cb4cff.xls

                                  856   +30°          is normal
                                  866   +61 to +89°   is normal
                                  876   +60°          is normal
                                  886   +31 to +59°   is normal
                                  887   check data    check data

Coding (first and second lead in pairing to table, see documentation)
                     negative-negative        1       I & II: x100
                   negative-isoelectric       2       III & aVL: x10
                      negative-positive       3       aVF & aVR: x1
                   isoelectric-negative       4
                    isoelectric-positive      5
                      positive-negative       6
                      positive-isolectric     7
                       positive-positive      8




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                                     14874a99-c5a5-42ca-bb69-939522cb4cff.xls




                                                                              Novosel D, Noll G, Luscher TF. Corrected for
                                                                              Externer Psychiatrischer Dienst, Haselstrasse

                               I            II           III            aVF   The calculation of the heart axis in the fronta
  Net R-S mm ±                                                                use of combination of bipolar (I, II, III) and un
enter sum of R wave and S wave; eg if R is +5 and S is -8, enter '-3'         Calculation of the electrical axis from leads I
                                                                              Arctan (aVF/I) results in lower values (in our
                                                                              that uses leads I and II: EA= Arctan ((2*II
                                           axis       axis interpretation     Bonferroni correction) or with corrected form
   ECG axis using I and aVF                       °    northwest axis         (axis = 374 degrees, n=48; p<0.005, paired t
                                                                              required because the unipolar and bipolar lea
       ECG axis using I and II                    °    right axis deviation   clinical significance, our results suggests tha
                                                                              calculation of the electrical axis.
      ECG axis using I and III                    °    northwest axis


      -90° to -29° = left axis deviation                                                          0°
      -30° to +110° = normal axis
    +111° to +180° = right axis deviation
    ±180° to -90° = "northwest axis"
("northwest axis" is commonly seen in congenital heart disease,               Singh PN, Athar MS. Simplified [correction of
dextrocardia, and sometimes in severe COPD)                                   electrocardiogram. Indian J Physiol Pharmaco
                                                                              Department of Physiology, Faculty of Medicin
                                                                              In clinical practice assessment of the mean Q
                                                                              ventricles or conduction blocks. The method
                                                                              leads has inherent element of subjectivity of a
                                                                              ambiguity about differentiation of left axis dev
                                                                              or complete/hemi block of the left bundle bran
                                                                              correct diagnosis. Though a formula based o
                                                                              for accurate measurement of axis, considerin
                                                                              only method for accurate measurement of the
                                                                              respective axes which is not practicable in cli
                                                                              accurate assessment of MQRSA, some autho
                                                                              ventricular hypertrophy with a broad S
                                                                              correct measurement of MQRSA, we have de
                                                                              and Lead-III. The formula derived is as follow
                                                                              in Lead-I and III, theta = angle subtended wit
                                                                              or the table. In case net voltage of QRS comp
                                                                              180degrees to find the angle of mean QRS v




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                                             14874a99-c5a5-42ca-bb69-939522cb4cff.xls




 G, Luscher TF. Corrected formula for the calculation of the electrical heart axis. Croat Med J. 1999 Mar;40(1):77-9.
 atrischer Dienst, Haselstrasse 1, CH - 5401 Baden, Switzerland. dragonovosel@hotmail.com
  of the heart axis in the frontal plane can be performed with the combination of any two leads. The
ation of bipolar (I, II, III) and unipolar leads (aVR, aVL and aVF) can produce wrong results.
 he electrical axis from leads I and aVF without correction (sometimes used in ECG recorders): EA=
results in lower values (in our study: 34 4 , n = 48) as compared to the values obtained with formula
  I and II: EA= Arctan ((2*II-I)/(Sqr(3)*I)) (axis = 33+/-7 degrees, n=48; p<0.005, paired t-test with
 ection) or with corrected formula which uses leads I and aVF: EA=+/-Arctan ((2*aVF)/(Sqr(3)*I))
grees, n=48; p<0.005, paired t-test with Bonferroni correction). The correction factor 2/Sqr(3) is
 se the unipolar and bipolar leads have different strengths. Although the difference rarely reach
ance, our results suggests that the ECG recorders should be proofed on formulas used for the
he electrical axis.




r MS. Simplified [correction of Simlified] calculation of mean QRS vector (mean electrical axis of heart) of
am. Indian J Physiol Pharmacol. 2003 Apr;47(2):212-6.
Physiology, Faculty of Medicine, A.M.U. Aligarh.
 ce assessment of the mean QRS axis (MQRSA) provides information related either with hypertrophy of the
 nduction blocks. The method adopted by clinicians i.e. the inspection of the QRS voltage in six of the limb
 ent element of subjectivity of approximately 10degrees. Moreover, in certain condition, when there is
 t differentiation of left axis deviation assessed by inspection method in to either hypertrophy of left ventricles
mi block of the left bundle branches, accurate measurement of the axis becomes necessary to arrive at the
 is. Though a formula based on area under R wave and S-wave of the same QRS complex has been derived
easurement of axis, considering its use in the computer software, working with ordinary electrocardiograph the
r accurate measurement of the QRS axis is plotting method i. e. the net voltages in Lead-I, and III on their
s which is not practicable in clinical settings. Although, calculation of MQRSA by area method gives an
 sment of MQRSA, some authors prefer measurement of axis by voltage method, as in cases of the right
ertrophy with a broad S-wave calculation of axis by area method may give erroneous results. Hence, to obtain
ement of MQRSA, we have derived a simplified formula based on the net voltage of QRS complexes in Lead-I
he formula derived is as follows, Tan(theta) =(I + 2III) divided by sqrt [3I], where I and III represent net voltage
I, theta = angle subtended with the axis Lead-I. The value of theta can be found by using scientific calculator
case net voltage of QRS complex in Lead-I being negative, the value of the theta should be subtracted from
find the angle of mean QRS vector.




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Mar;40(1):77-9.




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                               14874a99-c5a5-42ca-bb69-939522cb4cff.xls

 Purpose: To determine the electrical axis of                                                   Citations with
 the QRS complex in the horizontal plane by                                                     documentatio
 examining the precordial leads (V1 through                                                      n. 07.16.02
                       V6).
data
Are you trying to determine the    enter
electrical axis for the QRS
complex in the horizontal
plane? of the N)
Are all (Y or precordial leads              Y :-):-):-)
predominantly negative? (Y or
N) all of the precordial leads
Are                                         n :-):-):-)
predominantly positive? (Y or
N)                                          n :-):-):-)

          enter an 'x' in the appropriate column for the most isoelectric lead (give only 1 answer)

                                       V1               V2         V3     V4           V5             V6

most isolectric precordial lead                                            x

calculate                            result
data complete?                            Yes
evaluation appropriate?                   Yes :-):-):-)
The electrical axis for the QRS
complex                                     is normal




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                    14874a99-c5a5-42ca-bb69-939522cb4cff.xls

Sriram & Svirbely
      1999




 Yes        4




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                                  14874a99-c5a5-42ca-bb69-939522cb4cff.xls


  Purpose: To correct the Q-T interval for various                   Citations with Sriram &
                   heart rates.                                     documentation Svirbely 1997
                                                                      . 07.26.01


conversion                                enter
duration in msec                                  350 msec equals           0.35 seconds

data                                      enter
heart rate per minute                            50 beats/min
Q-T interval in seconds                        0.39 seconds

calculate                                results
data complete?                                 Yes
R-R interval (in seconds)                      1.21 seconds
Q-T corrected                                  0.35 seconds




                                                     Page 11
                              14874a99-c5a5-42ca-bb69-939522cb4cff.xls

 Purpose: To identify the location of atrioventricular                     Citations with Sriram &
 (AV) block by examining the changes in the ECG.                          documentation Svirbely 1999
                                                                            . 07.15.01


data                                        enter
Does the patient have evidence of
AV block? (Y or N)                                       Y :-):-):-)
QRS duration in seconds                                    seconds
Are conducted beats present? (Y or N)                      enter Y or N
Is the PR interval constant? (Y or N)                      enter Y or N
Are RP intervals variable? (Y or N)                        enter Y or N

calculate                                   result
data complete?                                    No
evaluation appropriate?                 complete data :-):-):-)
block located in AV node?               complete data
block in common bundle?                 complete data
block located in bundle branches?       complete data
block cannot be localized?              complete data
Should a temporary pacemaker be
inserted into the patient?              complete data




                                                         Page 12
                             14874a99-c5a5-42ca-bb69-939522cb4cff.xls

  Purpose: To diagnose left ventricular hypertrophy                    Citations with Sriram &
from electrocardiographic changes using the criteria                  documentation Svirbely 1998
                  of Casale et al.                                      . 07.05.03


conversion                                enter
peak height in mV                                      mV equals                  0 mm

data                                      enter
gender of the patient (M or F)                         enter M or F                  check data
Is the patient in normal sinus rhythm?
(Y or N)                                               enter Y or N

:-):-):-)                                              :-):-):-)
QRS wave duration in seconds                           seconds
P terminal force in V1 in mm•sec                       mm•sec

         peak height in mm               R wave           S wave        T wave
                                    V1                                              mm
                                    V3                                              mm
                                   aVL                                              mm

calculate                                 result
data complete?                                   No
value of voltage equation              complete data mm
                 which indicates LVH iscomplete data
multiple logistic regression equation complete data
                 which indicates LVH iscomplete data




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                            14874a99-c5a5-42ca-bb69-939522cb4cff.xls

 Purpose: To identify changes in the electrocardiogram associated with altered   Citations with documentation.
                         concentrations of potassium.                                       07.23.01

data
Are you evaluating an ECG for            enter
changes associated with potassium
levels? (Y or N)                                 Y :-):-):-)

   enter an "x" in the appropriate column for each finding (give only 1 answer per row)
                                                                              increased
                                                                              amplitude
                                         absent     flattened      normal    and/or width
P wave                                                   x                                       Yes       1
                                         normal    prolonged
PR interval                                 x                                                    Yes       0
                                         normal    prolonged      AV block
QRS interval                                x                                                    Yes       0
                                      depressed      normal      increased
ST segment                                  x                                                    Yes       2
                                       increased
                                       amplitude
                                     and/or width    normal       flattened    inverted
T wave                                                                 x                         Yes       2
                                         normal    prominent
U wave                                      x                                                    Yes       0
                                                   ventricular   premature      tachy-
                                         normal    fibrillation     beats    arrhythmias
rate and rhythm                             x                                                    Yes       0

calculate                                result
data complete?                                Yes
evaluation appropriate?                       Yes :-):-):-)
number of findings associated with
hyperkalemia                                     1
number of findings associated with
hypokalemia                                      2




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                                    14874a99-c5a5-42ca-bb69-939522cb4cff.xls


  Purpose: To diagnose myocardial injury from
the patterns of cardiac markers seen over time.


data                                       enter
age of patient in years                        55 years
gender of patient (enter M or F)                M :-):-):-)

                 Test                                 enter laboratory findings over time
                                           Initial 3 hour 6 hour 12 hour 18 hour 24 hour 48 hour
total CK (U/L)                                 200     210     220       250     230       225 199
CK-MB (ng/mL)                                    25     26       30        35      32       30   20
myoglobulin in µg/L                              90    100     100         80      70       60   50
troponin T in µg/L                            0.05    0.15      0.2       0.3     0.2     0.25  0.3
troponin I in µg/L                                3      4        6         8       7        5    6
total LD (U/L)                                 400     410     420       450     475       500 600
LD1 as percent total of LD (enter
from 0 to 100)                                  30           30         31       32         34        36        40
LD2 as percent of total LD (enter
from 0 to 100)                                  36           36         37       38         38        39        40

intermediate calculation                    Initial 3 hour 6 hour 12 hour 18 hour 24 hour 48 hour
CK-MB index                                 12.50     12.38  13.64  14.00   13.91   13.33   10.05
troponin T as multiple of upper limit
of normal                                    0.50       1.50          2.00     3.00       2.00      2.50      3.00
troponin I as multiple of upper limit of
normal                                       0.97       1.29         1.94      2.58      2.26       1.61      1.94
amount LD1 in U/L                             120        123        130.2       144     161.5        180       240
amount LD2 in U/L                             144      147.6        155.4       171     180.5        195       240
LD1-to-LD2 ratio                             0.83       0.83         0.84      0.84      0.89       0.92      1.00

intermediate evaluation                    Initial 3 hour 6 hour 12 hour 18 hour 24 hour 48 hour
                              total CK normal increasedincreased                    increased normal
                                                                  increased increased
                             CK-MB is:increasedincreasedincreasedincreasedincreasedincreasedincreased
                     CK-MB index is:increasedincreasedincreasedincreasedincreasedincreasedincreased
                       myoglobulin is: normalincreasedincreased normal normal normal normal
                         troponin T is: normalincreasedincreasedincreasedincreasedincreasedincreased
                          troponin I is: normalincreasedincreasedincreasedincreasedincreasedincreased
                               LD1 is:increasedincreasedincreasedincreasedincreasedincreasedincreased
                               LD2 is:increasedincreasedincreasedincreasedincreasedincreasedincreased
                   LD1-to-LD2 ratio is:increasedincreasedincreasedincreasedincreasedincreasedincreased

peak value seen at:                                               peak after infarct    injury relative to initial
• CK-MB                                         12   hours          12-24 hours            0-12 hours before
• troponin T                                    12   hours          10-24 hours        12 hours before to 2 after
• troponin I                                    12   hours          10-24 hours        12 hours before to 2 after
• LD1                                           48   hours          48-72 hours            0-24 hours before

interpretation
c/w normal? minor myocardial
suspicious for                                 No
injury?                                        No
c/w myocardial infarction?                    Yes


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                                     14874a99-c5a5-42ca-bb69-939522cb4cff.xls


c/w late presentation of MI?                       No
c/w skeletal muscle injury?                        No



Reference Range LD total                     low normal                   high normal
                                                  297                          537
Ref Range LD Isoenzymes                      low normal                   high normal   high in LD units
                                    LD1         0.156                        0.278           149
                                    LD2         0.318                        0.407           219
                                    LD3         0.176                         0.26           140
                                    LD4         0.071                        0.127             68
                                    LD5         0.062                        0.156             84

Reference Range Markers                         high normal
                              troponin T          0.1 µg/L
                               troponin I         3.1 µg/L
                              myoglobin            90 µg/L

total CK upper limit normal                    male  female
                                      20         200    165
                                      60         203     99

CK-MB
                    upper limit normal              5 ng/mL
                  upper limit borderline           10 ng/mL

time of infarct                               CK-MB
                                   initial   12-24 hours before
                                        3    9-21 hours before
                                        6    6-18 hours before
                                        9    3-15 hours before
                                       12    0-12 hours before
                                       18    6 hours before to after
                                       24    0-12 hours after
                                       48    24-36 hours after

                                              trop T
                                   initial   10-24 hours before
                                        3    7-21 hours before
                                        6    4-18 hours before
                                        9    1-15 hours before
                                       12    12 hours before to 2 after
                                       18    6 hours before to 8 after
                                       24    0-14 hours after
                                       48    24-38 hours after

                                               LD1
                                   initial   48-72 hours before
                                        3    45-69 hours before
                                        6    42-66 hours before
                                        9    39-63 hours before


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12   36-60 hours before
18   30-54 hours before
24   24-48 hours before
48   0-24 hours before




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                              14874a99-c5a5-42ca-bb69-939522cb4cff.xls


 Citations with Sriram &
documentation Svirbely 1997
. 06.07.01-.05




U/L
ng/mL
µg/L
µg/L
µg/L
U/L

per cent

per cent




U/L
U/L


# increased    # borderline
      5
      7             0
      7
      2
      6
      6
      7
      7
      7




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