2026 ECG Competition Answers (Part 2)

Annual UMEM Residency ECG Competition by Dr. Amal Mattu

This week we review the answers to questions 5-8 from the 14th Annual UMEM Residency ECG Competition. Make sure to attempt to answer the questions yourself before watching the video or clicking the answer boxes in the summary section to reveal the answers and take home points!

Instructions from Dr. Mattu: In some of the following questions, I'll ask you for a FULL ECG interpretation/diagnosis. Here's what I am asking for:

SAMPLE QUESTION: A 58 yo M presents with chest pain and the ECG noted below. What is the FULL ECG diagnosis? (5 points)

Sample Answer

Answer:
Sinus tachycardia, complete heart block, junctional escape rhythm, RBBB, diffuse ischemia

In this example, I would give you 1 point for identifying the atrial rhythm (ST), one point for identifying CHB, 1 point for identifying that there is a junctional escape, 1 point for identifying the RBBB, and one point for noting the ischemia (ST depression in multiple leads). In other words...be complete in your interpretation!

Be sure that you don't just describe what you see....interpret the ECG! For example, I don't want you to say "ST depression in __ leads." I want you to say "diffuse ischemia."

Also, in your interpretation, if you think there's an underlying issue, say it. For example, if you think the underlying dx is hyperK, or TCA OD, or Brugada, etc., say it.

Don't assume that points correlate with the number of things I am looking for. For example, if something is worth 3 points, that does NOT mean there are 3 things you need to list! Points are allotted based on how important I think something is.

Also, for all of the questions below, please assume that a cath lab is not immediately available to you.

5. A 33 yo W presents with reproducible chest wall pain and clinically was considered to be low-risk for ACS, but an ECG showed a T wave abnormality in leads V1-V3, seen below. What is the diagnosis? (2 points) Name 4 other conditions that can produce T wave inversions in leads V1-V3. (2 points)

Question # 5 Answer

Persistent juvenile T-wave pattern is a benign normal variant, but only when the pattern fits

The first case this week involves a 33-year-old woman with reproducible chest wall pain who is clinically low risk for ACS, but whose ECG shows T-wave inversions in V1–V3. Dr. Mattu identifies this as a persistent juvenile T-wave pattern.

This is a normal variant most often seen in young women, especially women of African descent. In children, T-wave inversions in the right precordial leads are common. As the left ventricle matures and becomes dominant, the T waves in V2 and V3 usually become upright. In some adults, this juvenile pattern persists.

Important features supporting a benign persistent juvenile T-wave pattern include:

  • T-wave inversions limited mainly to V1–V3
  • Shallow T-wave inversions, usually no more than 2–3 mm deep
  • Asymmetric T-wave inversions
  • Appropriate clinical context, such as low-risk or non-ACS presentation

Dr. Mattu cautions that this should not be overcalled in males, with deep T-wave inversions, symmetric T-wave inversions, or a concerning ischemic presentation.

Other causes of T-wave inversion in V1–V3 include RBBB, anteroseptal ischemia, pulmonary embolism, arrhythmogenic right ventricular cardiomyopathy, Brugada syndrome, RVH with strain, and WPW.

 

Question # 5 Answer

6. A 65 yo M non-English-speaker presents to triage “not feeling well” and he looks sick. BP is 85/55. An ECG is obtained in triage. People are trying to find the iPad translator for more hx… What is the most likely diagnosis? (2 points) Shortly after this ECG, the patient has a cardiac arrest. What is/are the most important medication(s) to call for? (2 points)

Question # 6 Answer

Massive STEMI can mimic a wide-complex rhythm when ST elevation merges into the QRS

The next case involves a 65-year-old man who presents to triage “not feeling well,” appears sick, and has a blood pressure of 85/55. He does not speak English, and while the team is trying to obtain more history, an ECG is obtained. Shortly afterward, he arrests.

At first glance, the precordial leads appear to show a wide-complex rhythm. Dr. Mattu uses this case to reinforce a key principle: if the patient is not actively in cardiac arrest, take a few seconds to look at all 12 leads.

The clue is lead aVL. It helps reveal that the QRS complex is not truly wide. Instead, the ECG shows massive ST-segment elevation, with the ST segment merging into the QRS complex in the precordial leads, creating a pseudo-wide-complex appearance.

This is not hyperkalemia, ventricular tachycardia, or sodium channel blocker toxicity. It is a massive STEMI.

The second part of the question asks what medication is most important after cardiac arrest when a cath lab is not immediately available. In that situation, Dr. Mattu’s answer is empiric thrombolytics.

Question # 6 Answer

7. A 67 yo M presents with chest pain. BP is 105/65. What is the most likely diagnosis? (2 points) Aside from T wave inversions, what are 4 other ECG findings that are often found in this condition? (2 points)

Question # 7 Answer

T-wave inversions in both the right precordial and inferior leads strongly suggest pulmonary embolism

The third case involves a 67-year-old man with chest pain and a blood pressure of 105/65. The ECG shows T-wave inversions in V1–V4 and in the inferior leads.

Dr. Mattu emphasizes that T-wave inversions in V1–V3 have a differential, but the combination of right precordial/anterior-septal T-wave inversions plus inferior T-wave inversions is highly predictive of pulmonary embolism.

This pattern reflects right ventricular strain.

Other ECG findings that may be seen in PE include:

  • Sinus tachycardia
  • S1Q3T3 pattern
  • Right axis deviation
  • Tall R wave in V1
  • Incomplete RBBB
  • ST elevation in right-sided leads, especially V1 and aVR, particularly with large PE

Dr. Mattu notes that S1Q3T3 is often overemphasized, but it remains part of the classic teaching. The broader point is that PE can produce multiple signs of right heart strain, and the distribution of T-wave inversions can be particularly helpful.

Question # 7 Answer

8. A 34 yo M runner presents with vomiting and severe malaise after a tough cardio workout. BP is 110/65. What is the most likely diagnosis? (2 points) What is the treatment? (2 points)

Question # 8 Answer

Benign early repolarization in athletes can mimic Wellens syndrome

The fourth case involves a 34-year-old male runner with vomiting and severe malaise after a difficult cardio workout. His blood pressure is 110/65. The ECG may look alarming because of the anterior T-wave morphology, but Dr. Mattu identifies this as a benign early repolarization variant, not Wellens syndrome.

This pattern is especially described in young athletic men, particularly men of African or Caribbean descent.

Key features supporting benign early repolarization rather than Wellens include:

  • Very high QRS voltage
  • J-point notching or “fish-hook” morphology
  • Concave-upward ST segment
  • Steep descent into the T wave after the J-point notch
  • Lack of classic Wellens morphology in the proper ischemic context

Dr. Mattu stresses that high-voltage QRS complexes can distort repolarization and create abnormal-appearing T waves. In general, he cautions against diagnosing Wellens syndrome in the setting of very high voltage.

This patient does not need ACS therapy or cath lab activation based solely on this ECG pattern. The appropriate treatment is supportive care, including fluids and antiemetics.

Question # 8 Answer
Key Teaching Points
  1. Persistent juvenile T-wave pattern is a benign normal variant, usually limited to V1–V3, shallow, asymmetric, and seen most often in young women.
  2. Do not dismiss all right precordial T-wave inversion as benign. Important mimics include LAD ischemia, PE, ARVC, Brugada syndrome, RVH with strain, RBBB, and WPW.
  3. Massive STEMI can look like a wide-complex rhythm when extreme ST elevation merges with the QRS complex.
  4. Look at all 12 leads before anchoring. In the massive STEMI case, lead aVL helps reveal that the QRS is not truly wide.
  5. If STEMI is followed by cardiac arrest and no cath lab is immediately available, thrombolytics may be the critical medication.
  6. T-wave inversions in both V1–V3 and the inferior leads strongly suggest PE with RV strain.
  7. Benign early repolarization in athletes can mimic Wellens syndrome, especially when high voltage distorts repolarization.
  8. High QRS voltage, J-point notching, and concave ST morphology favor benign early repolarization over Wellens.