ECGs FOR THE EMERGENCY PHYSICIAN
90.
SVT, rate 210. The rhythm is narrow-complex and regular; the differential includes ST, SVT, and atrial flutter. Close inspection for atrial activity reveals retrograde P-waves, often present in SVT, best noted in lead V1. Electrical alternans and mild ST-segment depressions are noted in some leads. These abnormalities are also occasionally found in SVT and are without clinical significance.
91.
ST, rate 120, incomplete RBBB, T-wave abnormality consistent with inferior and anteroseptal ischemia. The ECG is highly suggestive of acute massive pulmonary embolism, similar to cases #74 and #82. The ECG abnormalities of pulmonary embolism are transient in nature, usually lasting weeks to months. However, RVH and its associated ECG abnormalities may develop if chronic pulmonary hypertension develops. A ventilation-perfusion scan in this patient demonstrated multiple pulmonary emboli.
92.
SR, rate 85, incomplete RBBB, T-wave abnormality consistent with inferior and anterolateral ischemia. In 1982, Wellens and colleagues1 described two T-wave morphologies in the mid-precordial leads that are highly specific for a large proximal left anterior descending artery (LAD) obstructing lesion. The more common morphology is a symmetric and deeply inverted T-wave appearance, as shown in this case. The less common type is the biphasic T-wave morphology, as shown in case #33. The T-wave abnormality, which has come to be known as Wellens’ sign, usually persists even in the pain-free state. Medical treatment is often unsuccessful in preventing MI or death; invasive therapy with angioplasty or stent placement is most successful. This patient was found to have a >90% proximal LAD obstructing lesion. She was successfully treated with angioplasty.
(i)
(ii)
(iii)
V2
V4 V3
Deeply inverted T-waves in the mid-precordial leads characteristic of Wellens’ syndrome
The less common, biphasic T-wave pattern of Wellens’ syndrome
For comparison purpose, T-wave inversions of non-Wellens’ acute coronary ischemia
93.
SR, rate 88, persistent juvenile T-wave pattern. Normal young adults, especially women, may have a persistence of the T-wave inversions in leads V1−V3 that are usually present in children and adolescents. This is referred to as a “persistent juvenile T-wave pattern.” These T-wave inversions are asymmetric and shallow. If the inversions are symmetric or deep, myocardial ischemia should be assumed.
94.
ST, rate 140, LVH. ST or atrial fibrillation with rapid ventricular response is common in severe hyperthyroidism. These tachydysrhythmias may precede other clinical manifestations of disease. Hyperthyroidism was confirmed in this patient.
74