“What’s a STEMI?” My partner is a retired police officer, who works once a week. He asks because just the day before, his neighbor was whisked off the cardiac cath table just before he was to have a scheduled procedure when the doctor said they had an emergency STEMI coming in.
Little does my partner know, but he has touched on one of my favorite topics. Instead of a three word answer, he gets an lecture.
STEMI
A STEMI, I tell him, stands for ST-Elevation myocardial infarction. It is sort of like the mother of all heart attacks. A coronary artery becomes occluded and the tissue beyond the occlusion starts to die. The heart is electrical. When we put someone on a heart monitor, what we are looking for is an electrical picture of the heart. If the heart's electrical system isn’t working, then the pumping muscle is endangered. The pump stops working, the patient dies.
An ST elevation is caused by the electricity having to detour around the area of the heart that is dying. It produces a distinct shape on the ECG. A full 12-lead ECG can actually pinpoint the area of the heart that is threatened. We respond to chest pains all day long, but chest pain rarely turns out to be an actual heart attack, and even rarer, an ST elevation heart attack.
STEMIs are great paramedic calls, I tell my partner. Once you spot one, that patient is relying on you to get him to the proper hospital on time and to make certain that hospital knows the patient is having a STEMI.
You need strong assessment and ECG skills to recognize a STEMI. You need persuasive skills to convince the hospital over the radio that this patient -- that they can’t see -- is indeed a real STEMI so they can mobilize the cardiac cath lab before your arrival. You have to be able to educate your patient about what is happening to him, and to be able to assure him that he is going to get the best care possible.
And you have a lot of general work to do. Get the patient on oxygen (usually a cannula will suffice), give them aspirin (life-saving), get them in a hospital gown (something I like to do to make the transition easier at the hospital), put in 2 IVs, give Nitro (unless it is right sided MI, some would argue don’t even give it in an inferior MI), consider morphine (with the same warnings), give Zofran (if the patient is nauseous), do repeat 12-leads (to see if the infarct is evolving), apply defib pads (in the event the tombstone ST suddenly becomes v-fib and you need to shock the patient), all while getting patient's history (meds, allergies, and demographics such as DOB, SS, phone, address, etc.) .
One of the nice points about a STEMI patient is while they are critically ill, they are usually working with you and are not combative or hard to manage like a patient with a stroke, pulmonary edema or a patient with ruptured esophageal varices.
STEMI Alerts
The local hospitals have all recently instituted various procedures for prehospital folks to activate the cath lab from the field. One hospital requires EMS to transmit a 12-lead, others ask us to contact medical control, and say, “I have a STEMI alert.” I mention that the EMS coordinator of one of the hospitals told me the other day that EMS crews are welcome to come up into the cath lab and watch the procedure if they bring a STEMI in.
The cath lab procedure involves passing a catheter into a patient’s groin(the femotal artery) and then snaking it up through the circulatory system and into the patient’s heart. The cardiologist injects dye to find the blockages and then inflates a balloon in the artery to clear the blockage. He then inserts a stent, a small drug-coated metal tunnel to keep the artery open. The sooner the artery is opened (and blood flow is restored), the less damage is done to the heart.
Door-to-Balloon Time
Hospitals judge themselves on their door-to-balloon time, meaning the time the patient enters the hospital to the moment the balloon is inflated in the heart restoring blood flow. The goal is 90 minutes. Nationwide less than half of all patients with STEMIs have this time met.
It used to be only cardiologists could activate the cath lab. (Activating the lab means clearing a table, getting the staff in place to begin the procedure). If someone came into the ED with chest pain, they would get triaged and worked up by a nurse. A 12-Lead ECG would be done, which would be presented to a doctor. The doctor who would look at it, and if it was concerning, he would evaluate the patient. If he thought the patient was having a STEMI, he would then call the cardiologist and describe the patient and the ECG. The cardiologist would then decide whether to come down and see the patient for himself or not.
Then the ED docs got so they could make the decision to activate the cath lab themselves. ECG and story in hand, they would call the cardiologist at home in the middle of the night and tell him they had a STEMI in the ED who needed to go to the cath lab. The cardiologist would throw on some scrubs and race out of the house, and head in to the hospital as his staff prepared the lab.
Now EMS can call the ED doc and ask for field activation. I radio in on Sunday afternoon that I have a STEMI coming in, a cardiologist on a golf course gets a page, and his foursome is suddenly a threesome minus a golf cart. Or on a regular day, in the case of my partner's neighbor, the cardiogist has to tell the patient he has just put on his table and started prepping for a routine procedure (an investigative look at coronary artery health) that a more important patient is on the way in. The neighbor will have to wait.
With earlier activations, door-to-balloon times have drastically decreased. Years ago, cardiologists had no idea about EMS. Now we are their new best friends because they recognize if we do our jobs in the field right, the door-to-balloon time will significantly decrease. It will improve their performance times, and most important of all, it will improve outcomes.
I spoke with a paramedic in Carolina recently who said their system is so far advanced, a person calling 911 with a complaint of chest pain will get a quicker door-to-balloon time then a person walking into the same hospital with a complaint of chest pain.
Some systems have an EMS-to-balloon benchmark of 120 minutes, while others try for 90 minutes with the goal being 30 minutes prehospital, 30 minutes in the ED and 30 minutes in the cath lab.
Thank You Letters
I tell my partner the last two STEMIs I did, I got wonderful letters from the patients, thanking me for saving their lives. The letters were so similar; it made me believe the cardiologists must have made a point of telling them that EMS had been crucial to their care. The last one I did, a man and his wife, a week to the day after they’d traveled lights and sirens in our ambulance to the hospital, stopped by the ambulance bay and brought cookies the wife had baked as well as the thank you letter she wrote. The man couldn't stop shaking my hand, and thanking me.
"So anyways," I finally conclude, “STEMIs are great paramedic calls.”
“Interesting,” my partner says. "I'm glad I asked."
911 Call
That afternoon we get a call for a thirty-year-old man at work short of breath with tingling in his arms.
So I’m thinking sounds like anxiety, hyperventilation, BS.
We arrive at the office building, and on entering, find a crowd of people standing around a cubicle. A young man lies on the ground by his desk. He is shivering. He is covered up to the neck with winter coats. He is ghostly pale. There is vomit in the waste basket. I touch his forehead and it is as soggy as a sponge. I ask him how he is doing, he answers in a forced whisper which I can’t understand. My plan is to just get him out to the ambulance and out of the sight of others and try to figure out what is going on. I am wondering if maybe he doesn’t have a stomach bug or something. He looks perfectly fit – a spitting image of Lance Armstrong, except he is so pale.
In the ambulance, I help sit him up so I can get his shirt off, which is soaked through with sweat. We put him on a cannula and I attach the monitor while my partner tries to get a quick blood pressure. The young man tells me he has been feeling weak with pains in his arms for about forty minutes. He says he vomited twice.
"I can't get a pressure," my partner says.
I glance at the monitor.
I don't need strong ECG skills to recognize this one. It's hitting me in the face. Game On.
I tell my partner to get in front and drive. Code three. He snaps to attention as we almost never go lights and sirens.
I do the 12-lead while I am asking the patient about his medical history. He has none, except he says his father had a heart attack at age thirty-eight.
“Am I having a heart attack?” he asks.
“Yes,” I say, “but we are going to take care of you.”
I get right on the radio. “I have a STEMI alert,” I say. While the age – 30 might make the listener balk – my description of the ECG, ST elevation in II, III and AVF with reciprocal changes in I and AVL, along with the patient’s presentation, cold, clammy, ghost pale, and the clincher – his father had an MI at 38 bring me the response, “Do you need anything besides the cath lab activated?”
On the ride in, the patient gets aspirin, two IVs, and Zofran for his nausea. When he complains the oxygen isn’t working, I switch him up to a nonrebreather. I apply the defib pads just in case.
The cardiologist meets us in the ED. He takes one glance at our ECG and starts explaining the procedure to the patient to get his consent.
And then it is off to the cath lab.
Cath Lab
Not just the patient, but my partner and I. Standing behind glass we get to watch everything. A cardiology nurse directs our attention to two computer monitors, one that shows the patient’s beating heart, the other his ECG. We watch as dye is injected in each of the coronary arteries. When they try to inject it in the RCA – the right coronary artery, it goes no where. 100% occlusion.
Next we see the balloon inflated and then on the ECG monitor after a brief period of the heart slowing down, suddenly the ST elevation disappears and moves down to the baseline as blood flow is restored.
(Note: Not my patient's image)
The cardiologist asks for the time. Door-to -balloon – 35 minutes. I calculate back to our end. 911-call to balloon – 62 minutes.
Activation Time – 1 minute
Response Time – 4 minutes
Scene Time – 8 minutes
Transport time - 12 minutes
Ambulance Bay to ED – 2 Minutes
ED/CathLab – 35 Minutes
The cardiologist inserts a stent, and then does an echocardiogram that shows the patient still has a strong functioning heart.
We have to clear to get back in service. We thank the cardiology nurse for letting us observe. As we leave ,the doctor calls to us, “Great job!”
Another Question
Walking down the hall, there is a definite bounce in my step.
Then my partner says to me, “Now that I know what a STEMI is, ‘What’s a ruptured esophageal varices?’”
I stop and look at him. He didn't just hex us, did he?
“I’m just messing with you,” he says. “I guess I’ll learn to be quiet from now on.”
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Here's two old posts on STEMIs that show the changes over time:
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Disclaimer: As always some details and characteristics have been changed to protect patient confidentiality.