ECG Review
A "Pressure" Phenomenon
By Ken Grauer, MD, Professor, Department of Community Health and Family Medicine, University of Florida. Dr. Grauer is the sole proprietor of KG-EKG Press, and publisher of an ECG pocket brain book.
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Figure: 12-lead ECG and lead II rhythm strip obtained from a 72-year-old man with hypertension, ESRD, and heart failure. Which one lead is of most concern to you? |
Clinical Scenario:
The 12-lead ECG and lead II rhythm strip in the Figure were obtained from a 72-year old man with severe hypertension and end-stage renal disease (ESRD), on dialysis. He presented in heart failure. How would you interpret his ECG given this clinical context? Which cardiac chambers are enlarged by ECG criteria? Which one lead is of most concern to you in interpreting this tracing?
Interpretation/Answer:
The ECG shows sinus rhythm at a rate just under 100/minute. All intervals are normal. There is LAD (left axis deviation), but not enough to meet criteria for LAHB (left anterior hemiblock), since the QRS complex is isoelectric in lead II (we estimate the axis to be right at -30°). Regarding chamber enlargement, LVH (left ventricular hypertrophy) is strongly suggested by the very deep S wave (nearly 25 mm) in lead V2, especially given the age of this patient with ESRD and heart failure. In addition, ECG criteria are met for both LAE (left atrial enlargement) and RAE (right atrial enlargement). RAE is suggested by the tall (2.5 mm) peaked P wave in lead II, and LAE by the very deep (1 mm) negative component of the P wave in lead V1. Regarding QRST changesonly a tiny q wave is seen (in lead aVL), transition is slightly delayed (occurs between lead V4 to V5), and ST-T wave changes are relatively subtle and most consistent with LVH (ST segment flattening in lead V6 and T wave inversion in leads I and aVL).
The ECG lead of most concern to us is lead I. Although there is no ST segment elevation, the ST segment is definitely coved in this lead. This is not usually seen simply with LVH. ST segment coving in a single lead without ST elevation is clearly not a specific finding. However, given the clinical context described here, comparison with a previous ECG on this patient, repeating his ECG the next day, and obtaining serial troponins should be considered to ensure that there is no acute infarction.
Finally we titled this ECG Review, "A Pressure Phenomenon" in reference to increased P wave amplitude seen in this tracing. P wave amplitude was dynamic in this patient, typically becoming much greater during episodes of fluid overload that resulted in heart failure (presumably reflecting increased intra-atrial volume and pressure during such episodes).
12-lead ECG and lead II rhythm strip obtained from a 72-year-old man with hypertension, ESRD, and heart failure. Which one lead is of most concern to you?You have reached your article limit for the month. Subscribe now to access this article plus other member-only content.
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