Abstract
The S1Q3T3 sign associated with cor pulmonale was first described by Sylvester McGinn and Paul White in 1935. It has since become an overlooked and relatively nonspecific finding associated with pulmonary embolism. We present this case to elucidate the importance for clinicians to promptly identify this electrocardiographic triad.
Key Words: electrocardiography, cor pulmonale, McConnell’s sign, right heart strain, pulmonary embolism
Graphical abstract
A 73-year-old woman with a history of primary hypertension, hyperlipidemia, status post-hemorrhagic stroke 3 weeks prior presented with complaints of progressively worsening exertional dyspnea, fatigue, and iatrogenic diarrhea from prescription laxatives from her prior discharge. Onset of symptoms was shortly after her discharge and progressively worsened. Vitals were as follows: Tmax 100.7℉, SpO2 97% (ambient air), pulse 98 beats/min, blood pressure 86/50 mm Hg, respiratory rate 20. On physical exam, lung sounds were clear to auscultation bilaterally. There was a grade II holosystolic murmur noted at the left upper sternal border. Per protocol, an electrocardiogram (ECG) was obtained, which revealed the following (Figure 1A):
Figure 1.
The McGinn-White Sign
(A) The electrocardiogram (ECG) on arrival at the emergency department (ED) revealing the notable S1Q3T3 sign, a nonspecific, but characteristic, finding of acute pulmonary embolism with subsequent cor pulmonale. (B) Detailed labeling of the triad of morphological ECG changes that correspond to the clinical disease process.
What is the Diagnosis?
Which clinical diagnosis is most likely represented by this electrocardiogram?
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A.
Dextrocardia
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B.
Cor pulmonale
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C.
Right bundle branch block
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D.
Chronic obstructive pulmonary disease
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E.
Right ventricular hypertrophy
B is the correct answer.
Discussion/Rationale
The ECG reveals the characteristic triad of the McGinn-White sign1: prominent S waves in lead I, Q waves in lead III, and T-wave inversion in lead III (Figure 1B). Choice A is incorrect: dextrocardia will produce right axis deviation with positive QRS complexes in lead aVR. Choice C is incorrect: a diagnosis of right bundle branch block requires RSRʹ pattern in V1-V3 with slurred S waves in lateral leads with QRS duration of >120 ms. Choice D is also incorrect: chronic obstructive pulmonary disease classically manifests as multifocal atrial tachycardia and is often associated with right axis deviation and low voltage complexes. Though a nonspecific phenomenon, the McGinn-White sign is still diagnostic of acute right ventricular strain and should prompt further investigation. Further work-up revealed a mild troponin T elevation of 0.08 ng/mL, believed to be due to demand ischemia. With initiation of intravenous fluids, this down trended to 0.046 and then 0.032 ng/mL. Mild lactic acidosis was present. Due to low-grade fevers and diarrhea, a viral illness was suspected. However, our patient insisted the diarrhea to be due to laxative misuse. Due to the new holosystolic murmur, a complete 2-dimensional echocardiogram was obtained xthat astonishingly revealed severe right ventricular dilatation with poor systolic function, tricuspid regurgitation, an inferior vena cava diameter of 3.8 cm (normal 1.2 to 1.7 cm), and classic right ventricular septal bowing with global hypokinesis sparing the apex—consistent with McConnell’s sign (Video 1).2 At this time, we revisited our ECG and immediately recognized the McGinn-White triad.
A STAT computed tomography of the chest revealed large-burden pulmonary emboli within segmental and subsegmental arteries of all 5 lobes (Video 2). The right ventricle to left ventricle ratio was 1.4. She underwent emergent thrombectomy and was eventually discharged home in stable medical condition. Twelve months later, she continues to do well on ambient oxygen with normal ejection fraction and cardiopulmonary function.
This extraordinary case elucidates the insidious presentation of acute cor pulmonale. Owing to the initial ECG obtained during triage and the subsequent echocardiogram, a timely diagnosis of severe acute cor pulmonale with impending obstructive shock secondary to pulmonary emboli allowed for prompt life-saving measures for our patient. Though the value of this triad in establishing a diagnosis of pulmonary embolism remains limited, it certainly may be utilized to signify severity in many instances. Despite this, findings remain variable and often overlap with other diseases, which limits its independent utility.3
Funding Support and Author Disclosures
The authors have reported that they have no relationships relevant to the contents of this paper to disclose.
Footnotes
The authors attest they are in compliance with human studies committees and animal welfare regulations of the authors’ institutions and Food and Drug Administration guidelines, including patient consent where appropriate. For more information, visit the Author Center.
Appendix
For supplemental videos, please see the online version of this paper.
Appendix
Transthoracic echocardiographic findings of McConnell’s sign and the “D sign” consistent with right ventricular overload.
Computed tomography of the chest revealing the extent of pulmonary thrombus burden as well as a significantly enlarged right ventricle.
References
- 1.McGinn S., White P.D. Acute cor pulmonale resulting from pulmonary embolism. JAMA. 1935;104:1473–1480. [Google Scholar]
- 2.McConnell M.V., Solomon S.D., Rayan M.E., Come P.C., Goldhaber S.Z., Lee R.T. Regional right ventricular dysfunction detected by echocardiography in acute pulmonary embolism. Am J Cardiol. 1996;78:469–473. doi: 10.1016/s0002-9149(96)00339-6. [DOI] [PubMed] [Google Scholar]
- 3.Nazeyrollas P., Metz D., Jolly D., et al. Use of transthoracic Doppler echocardiography combined with clinical and electrocardiographic data to predict acute pulmonary embolism. Eur Heart J. 1996;17:779–786. doi: 10.1093/oxfordjournals.eurheartj.a014946. [DOI] [PubMed] [Google Scholar]
Associated Data
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Supplementary Materials
Transthoracic echocardiographic findings of McConnell’s sign and the “D sign” consistent with right ventricular overload.
Computed tomography of the chest revealing the extent of pulmonary thrombus burden as well as a significantly enlarged right ventricle.