Here's an interesting case I pulled off the LIFENET Receiving Station.
Update: ECGs were retrieved from the archives of the LP12 for better data quality.
82 year old male complaining of chest pain.
PMH: HTN, including pulmonary hypertension
Meds: Unknown antihypertensives, ASA
Vital signs:
Resp: 20
Pulse: 60
BP: 120/73
SpO2: 96 on RA
Breath sounds: clear
Skin is cool, pale, and diaphoretic. The patient admits to mild dyspnea. He also admits to slight nausea but he has not vomited. He describes his pain as pressure and 6/10 in severity.
The cardiac monitor is attached.
A 12 lead ECG is captured.
What is your interpretation of this ECG?
Update: Here is the 12 lead ECG obtained on arrival at the ED.
Do you see why serial 12 lead ECGs are important?
Tom,I see the right bundle branch block, along with what I beleive to be the voltage criteria for LVH in aVL, but I am also seeing slight elevation in that lead with Concordant T Waves, however it is not reciprocated. I am also seeing the Concordance in V2, V3, with depression isolated in V3, along with elevation in aVR Discordant T Waves. aVR and aVL are both high viewing leads, but I am not sure what to call this, other than treat the patient and based on his presentation, follow Mona, run like hell and get him to a cardiac care center because of the complexity of the 12 Lead. Curious to know what you see in all of that.
Excellent observations with regard to the concordant T waves in leads aVL and V2! The Q waves in leads V1-V3 are also significant. Are you certain there are no reciprocal changes? Look very carefully at the inferior leads. There is subtle ST segment depression. How about the conduction disturbance itself? RBBB with LAFB and 1AVB. This is a so-called trifascicular block in the presence of suspected ACS. It would be a good idea to apply the pacer pads as a precaution, since 3AVB can happen suddenly, sometimes without an escape rhythm if the patient takes oral antiarrhythmics. The follow-up ECG for this case will remove all doubt as to what’s happening. Thanks for the reply!
Tom, Incredible. I have been passing your blog along to others that I work with. I follow the ekg_club as well as the E2B groups on yahoo and the wealth of knowledge passed on through those have been overwhelming. Thanks again for the education. Any by the way… where is that following 12 Lead??Christopher
Thanks for the positive feedback, Christopher! Stand by for the follow-up ECG.Tom
Nice change. DO you know what kind of time frame that went by in between the 12 Leads? What was the general outcome of the patient? Looking forward to the blog getting into the fascicular blocks, those are still eluding me in my reading.
The short answer is, RBBB with left axis deviation is a bifascicular block RBBB/LAFB until proven otherwise. RBBB with right axis deviation is a bifascicular block RBBB/LPFB until proven otherwise.It's often impossible to differentiate between bifascicular block RBBB/LAFB and RBBB with Q waves from previous inferior MI (two most common causes of left axis deviation are left anterior fascicular block and Q waves from inferior MI).LPFB is rare, and it's a diagnosis of exclusion. You have to rule out RVH which can be difficult (may even require nitpicking over P wave morphology).In clinical practice, I think in terms of bifascicular patterns. In other words, RBBB with left or right axis deviation. Or, in the case of wide complex tachycardias, an upright QRS complex in lead V1 with right or left axis deviation.One interesting phenomenon is ventricular rhythms that originate in the left anterior fascicle of the left ventricle will produce a bifascicular pattern RBBB/LPFB. Ventricular rhythms that originate in the left posterior fascicle of the left ventricle will produce a bifascicular pattern RBBB/LAFB.Sometimes this only makes sense if you look at a diagram of the His-Purkinje system. For example, in a bifascicular block RBBB/LAFB, the right bundle branch is blocked, and so is the left anterior fascicle of the left ventricle. So which remaining fascicle is unblocked (i.e., the first to depolarize during each cardiac cycle)? The left posterior fascicle! That's why rhythms that originate in the left posterior fascicle share the same QRS morphology.TomP.S. Less than 1/2 hour between the first and second ECG, although I've seen STEMI evolve much faster! I have another case that shows a similar progression in < 10 minutes.