Download Two causes in one patient for extremely low voltage on the

Two causes in one patient for extremely low voltage on the
electrocardiogram
William C. Roberts, MD, Melody Joy Sherwood, MD, and Paul A. Grayburn, MD
Figure 1. Electrocardiogram in the patient described. The standard is 20 mm, rather than the usual 10 mm.
An 80-year-old woman is described with two different causes (pericardial
effusion and cardiac amyloidosis) for low QRS voltage on the electrocardiogram. Total 12-lead QRS voltage (from the peak of the R wave to the
nadir of either the Q or the S wave, whichever is deeper) was only 34 mm
(10 mm standard in all leads), the lowest we have encountered among
331 previously reported patients with 10 different cardiac conditions.
A
mong the causes of extremely low voltage on the electrocardiogram are large pericardial effusions and cardiac amyloidosis. The occurrence of both conditions in the same
patient can lead to extremely low voltage on the electrocardiogram. The occurrence of such a situation prompted this report.
CASE DESCRIPTION
An 80-year-old woman with dementia was hospitalized because of worsening confusion and lower leg edema. She was known
to have systemic hypertension and diabetes mellitus. She was in no
acute distress. Her blood pressure was 85/60 mm Hg. Her body
mass index was 18 kg/m2. No abdominal organs or subcutaneous
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lymph nodes were palpated. The electrocardiogram showed total
12-lead QRS voltage of 17 mm (standard ≈ 20 mm; double standard) (Figure 1). An echocardiogram disclosed pericardial effusion,
thickened right and left ventricular walls, and low (≈20%) ejection
fraction (Figure 2). Both ventricular cavities were of normal size.
DISCUSSION
Total 12-lead QRS voltage was introduced in 1982 as a means
to predict the presence of left ventricular hypertrophy (1) (Figure 3).
Subsequently, total 12-lead QRS voltage has been described in 10
different disease states involving 331 patients and compared in all
to heart weight (2). It has been found to be a better predictor of
left ventricular hypertrophy than any previous criteria.
The concept of low QRS voltage was described initially when
only three electrocardiographic leads were available. The 12-lead
From the Baylor Heart and Vascular Institute and the Department of Internal
Medicine, Division of Cardiology, Baylor University Medical Center at Dallas, Texas.
Corresponding author: William C. Roberts, MD, Baylor Heart and Vascular
Institute, Baylor University Medical Center at Dallas, 3500 Gaston Avenue, Dallas,
TX 75246 (e-mail: [email protected]).
Proc (Bayl Univ Med Cent) 2017;30(2):228–229
a
b
c
d
Figure 2. Transthoracic echocardiographic views—(a) parasternal short-axis view, (b) short-axis parasagittal view, and (c) apical four-chamber view—showing a
brightly echogenic myocardium, thickened right ventricular and left ventricular walls, thickened valve leaflets, dilated right atrium, dilated left atrium, and a pericardial
effusion. (d) A “bulls-eye” map of peak systolic longitudinal strain showing the characteristic “cherry-on-top” pattern of myocardial amyloidosis with preserved strain
at the apex (dark red center) and abnormal strain elsewhere (pink or blue).
total QRS voltage has rarely been employed as an indicator of
low QRS voltage. Among the 10 conditions in which total QRS
voltage was measured and reported, those with the lowest voltage
included cardiac amyloidosis, 58–199 mm (mean 104); cardiac
adiposity, 73–210 mm (mean 120); and the carcinoid syndrome,
48–227 mm (mean 117). The lowest total 12-lead QRS voltage
among the previously described 331 patients was 58 mm. Thus,
to have an electrocardiographic total 12-lead QRS voltage of only
34 mm, as in the present patient, is indeed unusual.
A limitation of the present report is the lack of anatomic
confirmation of cardiac amyloidosis. The echocardiogram, however, is virtually diagnostic of extensive cardiac amyloidosis.
1.
2.
Figure 3. Various QRS complexes showing how each was measured. Reproduced
from Siegel and Roberts (1) with permission of the authors and the publisher.
April 2017
Siegel RJ, Roberts WC. Electrocardiographic observations in severe aortic
valve stenosis: correlative necropsy study to clinical, hemodynamic, and
ECG variables demonstrating relation of 12-lead QRS amplitude to peak
systolic transaortic pressure gradient. Am Heart J 1982;103(2):210–221.
Roberts WC, Filardo G, Ko JM, Siegel RJ, Dollar AL, Ross EM, Shirani J. Comparison of total 12-lead QRS voltage in a variety of cardiac conditions and its usefulness in predicting increased cardiac mass. Am J Cardiol 2013;112(6):904–909.
Two causes in one patient for extremely low voltage on the electrocardiogram
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