EMS is dispatched to a 72 year old male patient. Third party call. History of Parkinson's Disease. Patient is conscious. No further information.
On arrival, EMS finds a 72 year old Spanish-speaking male. Through an interpreter the lead paramedic determines that the patient became dizzy, fell down, and hit his head. A small hematoma is visible above the patient's right eye.
The patient is awake but somnolent. He is oriented to person, place, time, and event. The remainder of the neurological exam was normal.
Since the patient is not alert the crew applies manual C-spine stabilization and continues the exam.
The patient denies chest pain or shortness of breath.
Breath sounds are clear bilaterally.
The patient denies any significant medical history and states that he takes no medications.
Vital signs are assessed.
- Resp: 18
- Pulse: 80
- BP: 104/70
- SpO2: 98 on RA
The cardiac monitor is attached.
*** UPDATE ***
The first complex in lead III helps foster the perception, probably due to wandering baseline.
Compounding the illusion is the ST-depression in lead aVL! This is one of the first things I look for when considering the ECG diagnosis of acute inferior STEMI.
It's helped me pick up on dozens of subtle presentations!
This is important for two reasons. First, it fools your eye into the thinking that ST-segment elevation is present. Secondly, it fools the GE-Marquette 12SL interpretive algorithm!
Having said that, I have respect for the GE-Marquette 12SL interpretive algorithm, and I'm certain it also picked up on the ST-depression in lead aVL.
Keep in mind that the ACC/AHA STEMI criteria is far from perfect. I've called STEMIs before with less than 1 mm of ST-segment elevation, specifically when ST-depression was present in lead aVL.
This case demonstrate that sometimes, the emergency department is exactly where a suspected acute STEMI patient (with a marginal ECG) belongs until the diagnosis can be confirmed through other means.
I'll be posting the conclusion to the case in the next couple of days.
See also:
72 year old male CC: Unknown problem (man down) – Conclusion
3L shows rhythm about 80bpm which is either regular w/ artifact, or contains PAC/PJCs.12L shows 1mm STE II, III, aVF and flat/inverted T's in aVL. I'm thinking IWMI, maybe R sided involvement. Possibly a preload problem caused his syncopal episode.O2, IV, V4R/V5R, repeat 12L. Safe and expeditious transport to PCI capable facility.
Christopher (or the gentleman formerly known as C.Watford) – That was also my first impression of this ECG.So you would have called a STEMI Alert?Tom
how about we stop flapping around wasting yet more time with the machine and get the guy into hospital for suspected silent MI? o2, aspirin, but hold off the GTN due to possible inferior MI, monitor 3 lead enroute.Parkinsons induced artifact on 1st strip, technician error on second, machine failure on 3rd and ST elevation in lead 2 on the 4th- lets not waste more time on the equipment and look at our patient instead!
Anonymous -Taking the time to capture a 12-lead ECG with excellent data quality is not a waste of time, and it's certainly not "flapping around." It's mission critical.In this case, the 12-lead ECG isn't the best I've ever seen, but I applaud the crew for trouble-shooting the arm lead reversal and the loose lead electrode. That's exactly what they've been trained to do.Here are the relevant questions. What is your interpretation of the ECG? Do you think it's a STEMI? Would you call a STEMI Alert? Would you bypass a local non-PCI hospital?By all means, look at the patient, too!Tom
Can you fax the 12 lead through to the hospital as you are en route so they can open a cath lab and bypass triage to save time (and heart muscle!)?
Squeezey -Yes, we can!
It's usually not a complete bypass, but it definitely minimizes the time in the emergency department! That's exactly why it's not a waste of time obtaining a good tracing in the field!Tom
The ECG shows normal sinus rythm with normal axis deviation. ST elevation seen in II, III and aVF, reciprocal changes seen in aVL.Think about right ventricular involvment esp. with the history of collapse and hypotension.. V1 shows subtle ST elevation, but confirm the diagnosis by V4R.. O2, IV infusion, Heparin and transport the patient to PCI .
without complaints of chest pain I would not activate the cath lab but would get a stat echo in er and look for wall motion abnormalities.would also get stat ct of the brain.anticoagulation could be detrimental in the fact he hit his head
I'd call it a STEMI… in so far as you have ST elev in all the inferior leads. Think I'd do a right sided V4R-V5R, ASA, O2, fluid bolus and if I got the pressure up maybe a cautious spray of NTG.DaveO
Excellent case again Tom.Difficult to know what's best to do but a few points come to mind1. His history fits with arrhythmia rather than ischaemia (although the two could be related)2. His ECG does have 1mm ST elevation in II,III & aVF; we need his old ECGs and need to remember that he is pain free3. He needs a CT Head before we start giving the usual meds.If he turned up at my hospital (where we don't do PCI) I'd hook him up to a monitor, scan his head, look for an old ECG and have a chat to the cath lab but I think they'd probably watch and wait given the history so far. Mike
Difficult to definitively call it a STEMI. Some complexes absolutely have elevation, however in others the PR segment depression makes it look like elevation though none is present. All depends on where you measure the baseline, as the TP segment is often a little sloping. I agree that a head CT should happen before ASA admin(or repeat 12-leads show more defined elevation). interesting case…
Dr. Hillis – That was exactly my interpretation after reviewing this 12-lead ECG! The ST-depression in lead aVL did it for me! Tom
Anonymous – A bedside echo to look for wall motion abnormalities would be an excellent idea! As you say, any patient with an abnormal neuro exam needs a CT scan before being taken to the cath lab! Your point is also well taken with regard to anticoagulation.Tom
Anonymous (DaveO) – That's exactly along the lines of what I suspected when I first laid eyes on this series of ECGs! Tom
cardiologycases (Mike) – Excellent points! I especially like the idea of comparing to an "old" ECG if available.Cases like these demonstrate that sometimes bypassing the emergency department straight away isn't always a great idea! For home run STEMIs with classical presentations, maybe. But for marginal cases or unusual presentations, it's a great idea to confirm through other means! PCI is not a procedure without risk (nor is fibrinolysis).Tom
Innocent Bystander – Outstanding observations! You are absolutely correct. I will post some graphics to illustrate your points.Thanks for the comment!Tom
Hi Tom,By definition (ast least in my system) this guy is not having a STEMI as we need a hx of pain/discomfort less than 12 hrs duration to meetb PCI/Thrombolysis criteria…Would want a much better story before i was thinking silent/atypical MI…Agree with your blog post – this pt needs to be in an ED and have old ECGs compared etc. Also agree with anonymous – is this an example of excessive scene time? due to the "flapping about" trying to geta 12 lead.. I am reminded that Intra cerebral bleeds can also cause ST segment changes…….. In a study of ED patients with STE Brady (et. al.) apparently found thatLVH was by far the most common cause of STE, followed by STEMI/BBB, BER, Ventricular aneurysm, pericarditis and other less common non iscahemic causes.We all know the time is muscle mantra – but one of the key principles underpining my practice is "do no harm". Throwing heparin at a patient with an equivocal story for STEMI, recent head trauma and difficult history gathering (due to ESL) seems to be a good way of ending up in front of the coroner….Brady, W. (et al). (2001). Cause of ST segment abnormality in ED patients. American Journal of Emergency Medicine, 19, 25-28.
Anonymous -Cardiac monitor attached at 20:00:01. 12-lead 3 captured at 20:03:32. It takes more than 3 1/2 minutes before I start accusing people of flapping around! A far more likely scenario is that a STEMI gets missed because the crew is so anxious to get the show on the road.As for the story, it doesn't scream ACS but I wouldn't call it silent either as ACS occasionally presents as syncope.Requiring a history of chest discomfort (and a normal neuro exam for that matter) increases the specificity of a STEMI Alert, which is certainly desirable, but it also lowers the sensitivity. Either way, a 12-lead ECGs is indicated for syncope patients, and if it's worth doing it's worth doing right! So again, I take issue with the suggestion that the paramedics were dawdling on scene.I wrote about the study you referenced HERE and I'm usually the first to point out that acute STEMI is not the most common cause of ST-elevation in chest pain patients (let alone less common presentations).Having said that, this ECG shows no obvious signs of being a STE-mimic save the PR-segment depression in a couple of leads.In fact, the ST-depression in lead aVL strongly favors the ECG diagnosis of acute inferior STEMI.This ECG could fool just about anyone!Tom
Hi Tom,Take your point but arent you contradicting yourself a little agree yes 12 lead ECGs are important – but he needs to be in a place where definitive care can be offered – an ED …. not in an ambulance….. Were the 12 leads obtained on scene or enroute?…I do not think the risks of fibrinolysis or an occult/evolving head injury have been fully appreciated here……..
Anonymous -I'm a strong advocate of prompt, expertly performed primary PCI, which requires a high level of coordination between EMS, the emergency department, and the cath lab.Sometimes patients have classical chest discomfort and very persuasive 12-lead ECGs that show obvious STEMI.In those cases, the cath team can be called in from home while the patient is still in the field. The concept is known as "parallel processing" and is particularly important on nights, weekends, and holidays.Obviously you can't activate the cath lab while the patient is still in the field if you don't perform a 12-lead ECG with excellent data quality.I advocate capturing a 12-lead ECG with the first set of vital signs, and before MONA. I've seen too many 12-lead ECGs normalize after MONA.Waiting until the patient is loaded for transport to capture a 12-lead ECG causes needless delay during which time the cath team could be responding from home. Not to mention that from what I've seen, the data quality is much worse in a moving ambulance. Do it right. Do it early. Make it a habit. It's not a big deal and the increase in scene time should be minimal.Tom
Interesting case.In my area (not necessarily my department) he would have, at best, been boarded (poorly) and transported. Period, end of sentence. -Anonymous2 (not the "Throw em in the truck and go" guy)