ECG Cases

Sinus rhythm with left atrial abnormality. Most striking are tall right precordial R waves with pathologic inferior and lateral Q waves giving a "reverse" type R wave progression. There are also ST-T abnormalities in I, aVL, V6. Thus the patient has coronary artery disease (CAD), s/p large infero-(postero)-lateral myocardial infarction (MI) accounting for congestive heart failure (CHF) findings. Recall that differential diagnosis of tall right precordial R waves includes: 1) Normal/positional variants, 2) Right ventricular hypertrophy (RVH) (look for right axis deviation, P pulmonale), 3) Posterior/lateral MI (usually signs of inferior MI, too), 4) hypertrophic cardiomyopathy/idiopathic hypertrophic subaortic stenosis (HCM/IHSS), 5) right bundle branch block (RBBB), 6) Wolff-Parkinson-White (WPW ) variants with posterior/lateral pre-excitation 7) Duchenne muscular dystrophy (young men with myopathy).

🟢 Answer Case 33 🟢 👇👇👇👇👇

64-year-old man with increasing pedal edema. What is the ECG diagnosis?

🟡 Case 33 🟡 👇👇👇👇

The ECG shows sinus tachycardia with an indeterminate (not "indeterminant") axis and prominent T wave inversions in V1-V4 with delayed precordial transition zone (R=S in V6). QT is at upper normal limits and there is an S wave in lead I with a minuscule R in III, aVF. P waves are peaked (well, almost) in II. Obviously it doesn't take an Oslerian wizard to think of anterior ischemia when you see poor wave progression and T wave inversions. But you should always think about acute right ventricular (RV) overload ("strain") due to pulmonary embolus, etc. That's what this patient with history of deep vein thrombosis (DVT) had. Contrary to common wisdom, there is no diagnostic ECG in pulmonary embolus, but there are suggestive ones. Unfortunately, most of the time the ECG is non-specific; although, with a large PE, sinus tachcardia is usual. Possible other findings include: T wave inversions in the right to mid chest leads; Poor R wave progression--due to acute RV dilation; the latter may also lead to S1Q3 pattern simulating inferior myocardial infarction (MI); P pulmonale; RV conduction delays; right axis shift.

🟢 Answer Case 32 🟢 👇👇👇👇👇

39-year-old man with acute dyspnea and "muscle strain" in left leg.

🟡 Case 32 🟡 👇👇👇👇

Be careful here. This may look superficially like sinus but if you look in V1, you can see P waves just before the QRS (there is right bundle branch block (RBBB) and also P waves in the T wave (halfway in between) which are partly hidden. Atrial rate is about 150, ventricular rate 75. This is an atrial tachycardia with 2:1 block (paroxysmal atrial tachycardia or "PAT with block" if it occurs paroxysmally) which may be due to digoxin toxicity, atrial disease, etc. If you got this right, PAT yourself on back; if you choked on it, a more forceful interscapular blow may be indicated. (Note that "PAT" is often a misnomer since the tachycardia may be sustained. So the term "atrial tachycardia with block" is most accurate here.)

🟢 Answer Case 31 🟢 👇👇👇👇👇

82-yr-old woman. What is the rhythm?

🟡 Case 31 🟡 👇👇👇👇

You shouldn't! There are subtle but real ST elevations inferiorly (II,III and aVF) and in V5 and V6. Cath showed postero-basal hypokinesis and he underwent circumflex/obtuse marginal angioplasty after ruling in for a small MI. ST depressions here in aVL are reciprocal to primary ST elevations infero-laterally. Whenever you see ST depressions, always look in contralateral leads for ST elevations and remember that you do not get reciprocal ST elevations with acute ischemia.

🟢 Answer Case 30 🟢 👇👇👇👇👇

A 43-year-old man diagnosed with lateral subendocardial ischemia based on ST depressions in aVL. Do you agree?

🟡 Case 30 🟡 👇👇👇👇

The ECG shows sinus rhythm with a subtle (very, very subtle if you missed it) Wolff-Parkinson-White (WPW) pattern. Note shortish PR and delta wave, best seen in lead V4 (on zoomable PDF) as slurring of initial QRS, with tall R (positive delta wave) in V1, negative in aVL, compatable with lateral bypass tract. What is the differential diagnosis of a tall R in V1/V2? You should consider: 1) normal variant, esp children, but also some adults, or lead (mis)-placement; 2) altered chest/mediastinal configuration with the heart in a more rightward orientation; 3) posterior myocardial infarction (MI) (inferior/lateral ischemia/MI usually also seen); 4) right ventricular hypertrophy (usually associated with rightward axis); 5) WPW with a posterior or lateral bypass tract; 6) right ventricular conduction abnormality; 7) hypertrophic cardiomyopathy (HCM) with or without obstruction; 8) Duchenne muscular dystrophy (due to postero-basal fibrosis). One way of testing hypothesis (not included here) that this pattern is WPW variant would be to increase vagal tone modulation, e.g., during Valsalva maneuver. Increased vagal tone should slow conduction down the AV node, accentuating contribution of bypass tract conduction, and making the WPW pattern more apparent.

🟢 Answer Case 29 🟢 👇👇👇👇👇