ECG Review

Not Just Heart Failure

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. Dr. Grauer reports no financial relationship to this field of study.

Figure: 12-lead ECG and lead II rhythm strip obtained from a 90-year-old woman with acute dyspnea and diaphoresis.

Clinical Scenario:

The 12-lead ECG and lead II rhythm strip in the Figure was obtained from a surprisingly spry and fit 90-year old woman, who presented with shortness of breath and diaphoresis at the time this tracing was recorded. Her blood pressure was 90 systolic. She was not having chest pain. Although initially thought to be in heart failure, something else was the inciting event. What two entities does this ECG suggest?

Interpretation/Answer:

The lead II rhythm strip shows sinus arrhythmia with one PAC (premature atrial contraction) that is conducted with aberration. Overall QRS voltage on the 12-lead tracing is reduced. The PR and QRS intervals are normal, but the QT interval appears to be slightly prolonged in lead V2 (ie, more than half the R-R interval in this lead). There is marked LAD (left axis deviation), consistent with LAHB (left anterior hemiblock), since the QRS complex is predominantly negative in lead II. There is no ECG evidence of LAE (left atrial enlargement) or LVH (left ventricular hypertrophy). Deciding on right-sided chamber enlargement is more difficult, as we will see momentarily. Although Q waves are absent, there is diffuse ST segment coving (with a hint of ST elevation) and T wave inversion. Given the clinical scenario, acute evolving myocardial infarction has to be considered as one possible etiology for this patient's presenting symptoms. However, serum troponins were negative and the patient did not evolve acute infarction. The clue to the real problem lies with assessment of the QRS complex in lead V1, which shows a qR pattern consistent with IRBBB (incomplete right bundle branch block) and/or RVH (right ventricular hypertrophy). While not quite meeting criteria for RAE (right atrial enlargement), the P wave in lead II is nevertheless peaked. Thus, the shape of the P wave suggests "P pulmonale", even though P wave amplitude falls short of the required 2.5 mm). Considering the clinical context of acute dyspnea in an elderly patient with low QRS voltage, near P pulmonale, IRBBB, and marked axis deviation — the inferior and anterior T wave inversion may reflect right ventricular "strain" from an acute pulmonary pattern. The patient turned out to have extensive pulmonary embolism. Nitroglycerin was held, diuretics were balanced with gentle IV fluid infusion to maintain her blood pressure, and she was anticoagulated. Amazingly, the patient stabilized and fully recovered. Moral of the case: Inferior and anterior T wave inversion is not always ischemic in nature; it sometimes reflects right-sided "strain" which may suggest a primary pulmonary problem.