Acute Coronary Syndromes (ACS): ECG & Risk Patients

00:01 I'm gonna go through some of the elements in a little bit more detail.

00:04 When we talk about history and the heart score again, I mentioned you get a lot of points if you've got a really great history but what does that mean? Well classically, we're all taught in med school that patients with MIs have 10 out of 10 crushing sub-sternal chest pain that radiates down their left arm or up into their jaw.

00:23 The reality is that that presentation is more common in younger white men than in other members of the population and the presentation among women, minority patients, and the elderly is much more variable.

00:36 So we wanna think about coronary syndromes in the case of unexplained arm or jaw pain without chest pain.

00:43 We wanna think about it in patients who are dyspneic but don’t have chest pain, especially if their dyspnea is exertional.

00:49 We wanna definitely think about in our patients who have epigastric pain or indigestion.

00:54 That's kind of a classic presentation of MI that you don't wanna miss.

00:58 And we really wanna think about it in patients who have any kind of autonomic dysregulation.

01:03 So maybe they're just diaphoretic, or light headed, or fatigued, or nauseous.

01:07 These are patients in whom we wanna be concerned about coronary syndromes, especially our elderly patients.

01:14 Moving on to ECG changes.

01:16 I mentioned ST segment depressions.

01:18 Now remember, ST segment elevations indicate a STEMI.

01:23 So if your patient has significant ST elevations, we’re hopefully not even doing a heart score on them because they've already gone to the Cath Lab, right? So this is just for patients who have EKG changes that are not diagnostic of STEMI.

01:36 ST segment depressions are by far the most specific and concerning changes among these patients, and you can see some examples of significant ST depressions here outlined on the slide.

01:48 T-wave inversions are much less specific.

01:52 They can indicate coronary syndrome but they can actually indicate a lot of other things as well, and ST segments can flip among healthy volunteers placed under different types of physiologic stress.

02:02 So while it’s interesting to note, it’s not as diagnostic as an ST-depression and doesn't get you the same number of points.

02:09 Now a normal ECG gets you no points in the heart score but I do wanna emphasize, if you're really concerned about your patient having a coronary syndrome and their ECG is normal, consider getting serial ECGs.

02:21 A lot of times these patients will develop changes in 10, 20, 30 minutes after their initial presentation and you can have the opportunity to see the evolution of those changes and make better decisions about your patient.

02:35 So if you have a high level of suspicion, don't give up on the ECG.

02:39 Five to ten percent of patients who have confirmed coronary syndromes have normal ECG's at the time of hospital presentation.

02:47 I mentioned cardiac risk factors before, and I just wanna review what the classic cardiac risk factors are so you know which ones are included in the heart score.

02:56 The history of hypertension, diabetes, hypercholesterolemia, smoking, significant obesity, so a BMI of 30 or more.

03:09 Family history but only family history at a young age.

03:12 Older people unfortunately, just get coronary syndromes even without inheritable risk.

03:18 So if they had a father who was 78 when he had an MI that doesn't tell you a lot.

03:22 Whereas if dad was 42 when he had an MI, you should definitely be concerned about heritability.

03:28 And then lastly, any kind of known cardiovascular disease.

03:32 So prior coronary syndromes, TIA’s, strokes, peripheral arterial disease, any evidence of vascular disease one place should raise your suspicions for vascular disease in the heart.

03:44 So when we use the heart score, we stratify patients into low, medium, and high risk.

03:49 A patient with a score of zero to three is low risk and these patients have a very low incidence, less than one to two percent of having major coronary events within 30 days of their hospital presentation.

04:01 So these patients can be safely discharged.

04:04 By contrast, patients who were at the four to six level, they have an intermediate risk of having significant coronary events and they really merit observation, coronary risk reduction, and some type of testing to quantify how significant their coronary disease is, and identify which ones might benefit for more invasive testing or intervention.

04:28 Patients with heart scores of 7 to 10, these patients are high-risk.

04:32 They have up to a 65% chance of having major adverse coronary events within the next 30 days.

04:39 So these patients all need to be admitted, they all need aggressive medical management, and they should really be considered for early invasive testing.

04:48 In particular, coronary angiography with intervention if it's indicated by the angio findings.

04:55 So again, heart score includes history, EKG, age, risk factors, and troponin.

05:04 You put all of those together into a final score and stratify your patient accordingly.

05:11 So for moderate risk patients, I mentioned that they might need some type of noninvasive testing but what am I talking about? Really I’m talking about stress testing or coronary CT angiography.

05:23 So, we're not sticking a wire in the artery and taking pictures the way you would if you were performing a catheterization, but you are using IV contrast injected systemically in order to visualize the coronaries and get a sense of whether there any blockages.

05:38 Alternately, you can use stress testing which is done either with exercise or with medication, and is complemented by cardiac imaging to identify whether there's any evidence of ischemia under physiologic stress All of these modalities, nuclear medicine stress testing, echocardiographic stress testing, coronary CT angiography, they all have about 80-85% sensitivity so they're pretty good but not perfect tests, and that's why they can't be substituted for invasive coronary angiography in really high risk patients, because these are the patients who are at risk of having a false negative result on a non-invasive test.

06:29 So the sensitivity’s good for this moderate risk group but it's not good enough for the high risk group, very important concept.

06:37 Non-invasive testing can rule out coronary disease in low to moderate risk patients but not in high risk patients.

06:47 Management for these moderate risk patients is gonna include basically, a control of their risk factors, so blood pressure reduction, better control of their diabetes, lipid-lowering, smoking cessation, weight loss basically, behavioral interventions designed to enhance their overall cardiac health.

07:08 We also should place all of these patients on daily aspirin.

07:12 Daily antiplatelet therapy has been shown to reduce the incidence of coronary events, and can be very beneficial for this group who’s not gonna directly to the Cath Lab for further testing.

07:23 What do we do with those high risk patients? Well, I already told you, we’re not gonna be doing stress tests on them, right? 'Cause stress testing isn't good enough.

07:31 We are gonna bring them into the hospital to check serial troponins over a 6 to 12 hour period depending on your local protocols.

07:40 We’re gonna get serial ECGs to see if they evolve, ischemic ECG changes over time.

07:46 We’re gonna consider early coronary angiography.

07:49 Now, we’re not rushing these patients off to the Cath Lab from the ED but we are admitting them to the hospital, and considering performing catheterization the next day or the day after that so we can figure out what’s going on with them.

08:02 Really, coronary angiography is the gold standard for evaluation of ACS, and if you have a strong suspicion your patient has a coronary syndrome, you should be advocating for them to make the way to the Cath Lab at some point during their hospitalization.

08:18 In terms of management, again, all these patients should get aspirin but this is a group that should get more aggressive medical management.

08:25 So they should also get antiplatelet therapy with either Ticagrelor or Clopidogrel.

08:30 They should get anticoagulation typically with Heparin.

08:35 Oral beta blockade, again, if there’s not a contraindication to doing that.

08:39 They definitely if they do undergo angiography should receive angioplasty or stenting if it's indicated based on their angiographic results, and they should all get aggressive risk modification to lower their long-term coronary risk.

08:54 So in summary, coronary syndromes are a continuum of disease.

08:58 Not every patient with a coronary syndrome is gonna come in with a big dramatic MI and a classic looking ECG.

09:06 You do wanna check an ECG for everybody urgently, because you wanna identify that subset of patients who have STEMIs, 'cause that group needs to go rapidly to the Cath Lab and they need to get re-vascularized in order to save their jeopardized myocardium.

09:23 But for patients who don’t meet STEMI criteria, we wanna optimize medical management, reduce their risk, and certainly perform some type of coronary risk stratification to get to the bottom of which patients should go on and have further testing and which shouldn’t.

09:42 Patients who don't have STEMI again, based on the heart score, low risk can go home.

09:47 Intermediate risk should have non-invasive testing either stress testing or coronary CTA, and high-risk patients should be considered for invasive angiography at some point early in their hospital course.

10:03 Thank you, I hope that this was a helpful talk about management of coronary syndromes.