p3medic Posted May 25, 2009 Share Posted May 25, 2009 No it is not a definitive indicator for confirming a RBBB. However, it is not an uncommon finding in the presence of a BBB. However, the notching I see with this rhythm is significantly different from any rabbit ears pattern I have even seen. In fact, it does not even fit into any recognizable QRS pattern I know such as an RSR prime pattern. It looks somewhat like the dicrotic notch of an arterial waveform. (In V1 specifically.) With the notch on the descending slope of the waveform. This IMHO is more evidence to support the theory of ventricular tachycardia. Take care, chbare. Exactly. Look at v1 and v6, very unlike RBBB. Link to comment Share on other sites More sharing options...
Jeepluv77 Posted May 25, 2009 Share Posted May 25, 2009 ...the dicrotic notch of an arterial waveform... Huh? Any good cardio sites I can look this up stuff up on? I had a couple bookmarked but recently lost them due to having to reformat my harddrive. Link to comment Share on other sites More sharing options...
fiznat Posted May 25, 2009 Share Posted May 25, 2009 (edited) Excellent idea. How do you do that? Try making your text white. The user will have to highlight the text in order to read it. Example below (highlight it!): SECRET MESSAGE REVEALED, IT'S VT! Edited May 25, 2009 by fiznat Link to comment Share on other sites More sharing options...
FL_Medic Posted May 25, 2009 Author Share Posted May 25, 2009 (edited) THE ANSWER Ventricular Tachycardia The following is straight out of the Bob Page 12-lead book. Your primary survey of the WCT patient: 1. Measure the QRS width 2. Determine the axis 3. Look at morphology changes 4. Look at concordance criteria 5. Look at signs of AV dissociation 6. Get a good patient history 7. Do a physical exam Wide Complex Tachycardia > 150: Listed by ease of use, Often seen, & Specificity 1. Extreme right axis deviation (ERAD) & positve v1 2. QRS morphology in v1 3. QRS morphology in v6 4. ERAD & negative v1 5. Concordance in v1 through v6 6. RS interval > 100ms any V lead 7. QRS > 140ms if up & > 160ms if down in v1 Extreme right axis deviation: ERAD is also known as right-shoulder axis, northwest axis, intermediate axis or “no man’s land”. This is an axis > 180 degrees. You can determine this simply by looking at leads 1, 2 ,& 3. If leads 1, 2, & 3 are all negative, the patient has ERAD. If v1 is positive with ERAD, the rhythm is ventricular in origin. It is still possible for a ventricular rhythm to present with ERAD and negative v1, this is just lest specific. QRS Morphology: 1. When you have the “bunny ear” shape in v1. Having the left ear bigger than the right ear indicates VT. This is also referred to as “big mountain/little mountain”. 2. A single peaked upright R wave in v1 is indicative of VT 3. A single peaked upright R wave in v1 with slopped off end 4. A fat (> 40 ms) R wave in negative QRS in v1 5. A notched down stroke of negative QRS in v1 6. Any predominately negative complex in v6 suggests VT Concordance: 1. Negative concordance, meaning negative QRS complexes in v1 through v6, indicates VT or LBBB. 2. Positive concordance indicates VT or WPW Measurements: 1. Positive QRS in v1 > 140ms 2. Negative QRS in v1 > 160ms 3. RS Interval is highly reliable. From the start of the R wave to the nadir point of the S wave (the bottom point). > 100ms is VT AV Dissociation: 1. Cannon A waves. These are waves of pressure seen shooting up the jugular veins. 2. P waves out of place and isolated 3. Different S1 (first hear sound). Remember, we are trying to rule out VT. This means that if you have any of the criteria without strong conflicting criteria, call it VT. You can also try the tutorial on the prehospital 12 lead blog. FOR BONUS POINTS: Which ventricle is originating the impulse? Edited May 25, 2009 by FL_Medic Link to comment Share on other sites More sharing options...
chbare Posted May 25, 2009 Share Posted May 25, 2009 I would go with the left ventricle. We still have RAD suggestive of a possible inferior to superior movement. Going with the largest mass of tissue and most probable location for an ectopic focus (LV), and the axis, I would venture to say the left ventricle? Take care, chbare. Link to comment Share on other sites More sharing options...
fiznat Posted May 26, 2009 Share Posted May 26, 2009 (edited) I'm not sure I agree that this ECG has extreme right axis deviation. I use two methods to determine QRS axis, and by both methods this axis is in the right axis (bottom left quadrant), about +150 degrees. Method 1: The quick method using I and aVF. Negative lead I means that the axis is pointing away from the left shoulder, towards the right. A positive complex in aVF means that the axis is pointing downwards. Down and to the right is right axis deviation, not extreme right axis deviation. Method 2: Isoelectric lead. The most isoelectric limb lead here is lead II. The mean QRS axis should be at about 90 degrees from this lead. Since lead II is at about +60 degrees, our axis in this ECG should be about +150 degrees. By your own method ("leads 1, 2, and 3 all negative = ERAD") this still doesn't look like extreme right axis, as lead 3 is positive. In any case, I agree with you that this is still VT. Edited May 26, 2009 by fiznat Link to comment Share on other sites More sharing options...
chbare Posted May 26, 2009 Share Posted May 26, 2009 (edited) I'm not sure I agree that this ECG has extreme right axis deviation. I use two methods to determine QRS axis, and by both methods this axis is in the right axis (bottom left quadrant), about +150 degrees. Method 1: The quick method using I and aVF. Negative lead I means that the axis is pointing away from the left shoulder, towards the right. A positive complex in aVF means that the axis is pointing downwards. Down and to the right is right axis deviation, not extreme right axis deviation. Method 2: Isoelectric lead. The most isoelectric limb lead here is lead II. The mean QRS axis should be at about 90 degrees from this lead. Since lead II is at about +60 degrees, our axis in this ECG should be about +150 degrees. By your own method ("leads 1, 2, and 3 all negative = ERAD") this still doesn't look like extreme right axis, as lead 3 is positive. In any case, I agree with you that this is still VT. It does not have right shoulder axis deviation. The QRS would need to be negative in lead I, II, & III. I stated RAD, not right shoulder deviation, or extreme RAD. Take care, chbare. Edited May 26, 2009 by chbare Link to comment Share on other sites More sharing options...
FireMedic65 Posted May 26, 2009 Share Posted May 26, 2009 your patient presents with syncope and refractory dizziness For Larger Viewing Click the top of the ECG then hold Ctrl and hit +/- or scroll your mouse I need some feedback on these, what do you think?? Should I post the answers as a seperate topic titled "Strip Tease # Answer"? Would you like more of an explination of the rhythm, would this help you learn more? First off, yes, the ECG thing you are going is pretty cool and helpful to others who need the help with them, including myself. Second, this particular strip, was not "clickable", and therefor unable to make larger, unless you enlarged your whole screen (the whole forum/thread included). Third of which is just a suggestion. People who wish to contribute and answer the strip, they should do so using the "Insert Spoiler" option. Using this will allow others who want to discuss what is going on, and not see the results? Then have a discussion about it after the matter. Link to comment Share on other sites More sharing options...
FL_Medic Posted May 26, 2009 Author Share Posted May 26, 2009 Why was this moved to scenarios? Pretty upsetting. I'm not sure I agree that this ECG has extreme right axis deviation. I use two methods to determine QRS axis, and by both methods this axis is in the right axis (bottom left quadrant), about +150 degrees. Method 1: The quick method using I and aVF. Negative lead I means that the axis is pointing away from the left shoulder, towards the right. A positive complex in aVF means that the axis is pointing downwards. Down and to the right is right axis deviation, not extreme right axis deviation. Method 2: Isoelectric lead. The most isoelectric limb lead here is lead II. The mean QRS axis should be at about 90 degrees from this lead. Since lead II is at about +60 degrees, our axis in this ECG should be about +150 degrees. By your own method ("leads 1, 2, and 3 all negative = ERAD") this still doesn't look like extreme right axis, as lead 3 is positive. In any case, I agree with you that this is still VT. This strip doesn't have ERAD. This is Left Ventricular Tachycardia Link to comment Share on other sites More sharing options...
Tom B. Posted May 26, 2009 Share Posted May 26, 2009 You could go even further and say that the impulse originates in the area of the left anterior fascicle of the left ventricle. Why? What type of bifascicular block presents with an upright QRS complex in lead V1 and a right axis deviation? RBBB and LPFB. With RBBB and LPFB, which fascicle depolarizes first? The left anterior fascicle. Link to comment Share on other sites More sharing options...
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