The Journal of Emergency Medicine, Vol. -, No. -, pp. 1–3, 2014 Copyright Ó 2014 Elsevier Inc. Printed in the USA. All rights reserved 0736-4679/$ - see front matter
http://dx.doi.org/10.1016/j.jemermed.2014.01.032
Visual Diagnosis in Emergency Medicine
POINT-OF-CARE ULTRASOUND FINDINGS OF ACUTE PULMONARY EMBOLISM: MCCONNELL SIGN IN EMERGENCY MEDICINE Elizabeth P. Haller, BA,* David M. Nestler, MD, MS,† Ronna L. Campbell, MD, PHD,† and Venkatesh R. Bellamkonda, MD† *Mayo Medical School, Mayo Clinic College of Medicine, Rochester, Minnesota and †Department of Emergency Medicine, Mayo Clinic College of Medicine, Rochester, Minnesota Reprint Address: Venkatesh R. Bellamkonda, MD, Department of Emergency Medicine, Mayo Clinic College of Medicine, 200 First Street SW, Rochester, MN 55905
Computed tomography (CT) angiography of the chest revealed a saddle pulmonary embolism (PE; Figure 1). ED point-of-care ultrasound was performed to evaluate cardiac function. Using a phased-array transducer (Sonosite M-Turbo with P21x 5-1 MHz transducer;
INTRODUCTION This case highlights the utility of McConnell sign as an important part of point-of-care ultrasound in critically ill emergency department (ED) patients undergoing evaluation for pulmonary embolism (PE). CASE REPORT A 70-year-old man presented to the ED complaining of sharp, severe thoracic back pain. This had developed and worsened over the past week, and was associated with dyspnea on exertion. On physical examination, his heart rate was 154 beats/min, blood pressure was 107/68 mm Hg, and oxygen saturation was 94% on room air. Cardiac auscultation did not detect any murmurs, clicks, rubs, or gallops. Pulmonary examination revealed normal breath sounds. His lower extremities were symmetric and nontender. An electrocardiogram revealed sinus tachycardia.
Streaming video: One brief real-time video clip that accompanies this article is available in streaming video at www.journals.elsevierhealth.com/periodicals/jem. Click on Video Clip 1.
Figure 1. Computed tomography angiography reveals a pulmonary embolism (arrow) in the right and left pulmonary arteries.
RECEIVED: 26 August 2013; ACCEPTED: 31 January 2014 1
2
E. P. Haller et al.
Figure 2. McConnell sign in diastole and systole (arrows).
Sonosite, Bothell, WA), parasternal long-axis, parasternal short-axis, apical four-chamber, and subcostal views were obtained. Ultrasound showed grossly normal left ventricular contractility, however, the apical fourchamber view revealed an akinetic right ventricular (RV) free wall with normal contraction of the RV apex (Video). Based on the presence of a saddle PE, hemodynamic instability, and RV strain objectively demonstrated by echocardiography, the patient was admitted to the intensive care unit after initiating emergent anticoagulation. The patient suffered progressive hemodynamic compromise and died on hospital day 6. DISCUSSION Bedside transthoracic echocardiography enables emergency providers to rapidly and noninvasively assess cardiac function. The emergency evaluation of patients with suspected acute PE in the ED is often challenging, particularly when a CT scan is unsafe to perform due to hemodynamic instability or other contraindications. In such situations, the presence of McConnell sign can help risk stratify for the diagnosis of PE. McConnell sign consists of a sonographically akinetic RV free wall in conjunction with a normokinetic RV apex (Figure 2). McConnell et al. first described these findings in 1996 in a cohort of 126 patients with and without PE, using the apical four-chamber view of the echocardiogram (1). This finding was 77% sensitive and 94% specific for acute PE (1). Subsequent evaluations have found widely variable sensitivities, but specificities have
been as high as 96% (2). The pretest probability may be responsible for the variations in accuracy of McConnell sign. When applied directly to patients undergoing active evaluation for PE, Lodato and colleagues found McConnell sign to have the highest specificity of all echocardiographic findings for PE diagnosis, with a positive predictive value of 86% (2). The underlying mechanism responsible for McConnell sign is not definitively known. It has been postulated based on longitudinal velocity vector imaging that these findings are secondary to a visual illusion produced by the presence of a dilatated RV associated with tethering of the RV apex to a hyperdynamic left ventricle (3). McConnell sign has been reported in patients with pulmonary hypertension, RV infarction, and other conditions (3,4). Therefore, interpretation must be considered in the context of patient presentation as well as other studies such as electrocardiogram (5). Although McConnell sign cannot replace CT in the evaluation of acute PE, this finding can be used to assess the likelihood of disease and guide emergent therapy, particularly in patients too unstable or otherwise unable to undergo CT imaging. REFERENCES 1. McConnell MV, Solomon SD, Rayan ME, Come PC, Goldhaber SZ, Lee RT. Regional right ventricular dysfunction detected by echocardiography in acute pulmonary embolism. Am J Cardiol 1996;78:469–73. 2. Lodato JA, Ward RP, Lang RM. Echocardiographic predictors of pulmonary embolism in patients referred for helical CT. Echocardiography 2008;25:584–90. 3. Lopez-Candales A, Edelman K, Candales MD. Right ventricular apical contractility in acute pulmonary embolism: the McConnell sign revisited. Echocardiography 2010;27:614–20.
McConnell Sign in Emergency Medicine 4. Casazza F, Bongarzoni A, Capozi A, Agostoni O. Regional right ventricular dysfunction in acute pulmonary embolism and right ventricular infarction. Eur J Echocardiogr 2005;6:11–4. 5. Piazza G. Submassive Pulmonary embolism. JAMA 2013;309: 171–80.
3
SUPPLEMENTARY DATA Supplementary data associated with this article can be found, in the online version, at http://dx.doi.org/10. 1016/j.jemermed.2014.01.032.
Streaming video: One brief real-time video clip that accompanies this article is available in streaming video at www.journals.elsevierhealth.com/periodicals/jem. Click on Video Clip 1.
http://dx.doi.org/10.1016/j.jemermed.2014.01.032
Visual Diagnosis in Emergency Medicine
POINT-OF-CARE ULTRASOUND FINDINGS OF ACUTE PULMONARY EMBOLISM: MCCONNELL SIGN IN EMERGENCY MEDICINE Elizabeth P. Haller, BA,* David M. Nestler, MD, MS,† Ronna L. Campbell, MD, PHD,† and Venkatesh R. Bellamkonda, MD† *Mayo Medical School, Mayo Clinic College of Medicine, Rochester, Minnesota and †Department of Emergency Medicine, Mayo Clinic College of Medicine, Rochester, Minnesota Reprint Address: Venkatesh R. Bellamkonda, MD, Department of Emergency Medicine, Mayo Clinic College of Medicine, 200 First Street SW, Rochester, MN 55905
Computed tomography (CT) angiography of the chest revealed a saddle pulmonary embolism (PE; Figure 1). ED point-of-care ultrasound was performed to evaluate cardiac function. Using a phased-array transducer (Sonosite M-Turbo with P21x 5-1 MHz transducer;
INTRODUCTION This case highlights the utility of McConnell sign as an important part of point-of-care ultrasound in critically ill emergency department (ED) patients undergoing evaluation for pulmonary embolism (PE). CASE REPORT A 70-year-old man presented to the ED complaining of sharp, severe thoracic back pain. This had developed and worsened over the past week, and was associated with dyspnea on exertion. On physical examination, his heart rate was 154 beats/min, blood pressure was 107/68 mm Hg, and oxygen saturation was 94% on room air. Cardiac auscultation did not detect any murmurs, clicks, rubs, or gallops. Pulmonary examination revealed normal breath sounds. His lower extremities were symmetric and nontender. An electrocardiogram revealed sinus tachycardia.
Streaming video: One brief real-time video clip that accompanies this article is available in streaming video at www.journals.elsevierhealth.com/periodicals/jem. Click on Video Clip 1.
Figure 1. Computed tomography angiography reveals a pulmonary embolism (arrow) in the right and left pulmonary arteries.
RECEIVED: 26 August 2013; ACCEPTED: 31 January 2014 1
2
E. P. Haller et al.
Figure 2. McConnell sign in diastole and systole (arrows).
Sonosite, Bothell, WA), parasternal long-axis, parasternal short-axis, apical four-chamber, and subcostal views were obtained. Ultrasound showed grossly normal left ventricular contractility, however, the apical fourchamber view revealed an akinetic right ventricular (RV) free wall with normal contraction of the RV apex (Video). Based on the presence of a saddle PE, hemodynamic instability, and RV strain objectively demonstrated by echocardiography, the patient was admitted to the intensive care unit after initiating emergent anticoagulation. The patient suffered progressive hemodynamic compromise and died on hospital day 6. DISCUSSION Bedside transthoracic echocardiography enables emergency providers to rapidly and noninvasively assess cardiac function. The emergency evaluation of patients with suspected acute PE in the ED is often challenging, particularly when a CT scan is unsafe to perform due to hemodynamic instability or other contraindications. In such situations, the presence of McConnell sign can help risk stratify for the diagnosis of PE. McConnell sign consists of a sonographically akinetic RV free wall in conjunction with a normokinetic RV apex (Figure 2). McConnell et al. first described these findings in 1996 in a cohort of 126 patients with and without PE, using the apical four-chamber view of the echocardiogram (1). This finding was 77% sensitive and 94% specific for acute PE (1). Subsequent evaluations have found widely variable sensitivities, but specificities have
been as high as 96% (2). The pretest probability may be responsible for the variations in accuracy of McConnell sign. When applied directly to patients undergoing active evaluation for PE, Lodato and colleagues found McConnell sign to have the highest specificity of all echocardiographic findings for PE diagnosis, with a positive predictive value of 86% (2). The underlying mechanism responsible for McConnell sign is not definitively known. It has been postulated based on longitudinal velocity vector imaging that these findings are secondary to a visual illusion produced by the presence of a dilatated RV associated with tethering of the RV apex to a hyperdynamic left ventricle (3). McConnell sign has been reported in patients with pulmonary hypertension, RV infarction, and other conditions (3,4). Therefore, interpretation must be considered in the context of patient presentation as well as other studies such as electrocardiogram (5). Although McConnell sign cannot replace CT in the evaluation of acute PE, this finding can be used to assess the likelihood of disease and guide emergent therapy, particularly in patients too unstable or otherwise unable to undergo CT imaging. REFERENCES 1. McConnell MV, Solomon SD, Rayan ME, Come PC, Goldhaber SZ, Lee RT. Regional right ventricular dysfunction detected by echocardiography in acute pulmonary embolism. Am J Cardiol 1996;78:469–73. 2. Lodato JA, Ward RP, Lang RM. Echocardiographic predictors of pulmonary embolism in patients referred for helical CT. Echocardiography 2008;25:584–90. 3. Lopez-Candales A, Edelman K, Candales MD. Right ventricular apical contractility in acute pulmonary embolism: the McConnell sign revisited. Echocardiography 2010;27:614–20.
McConnell Sign in Emergency Medicine 4. Casazza F, Bongarzoni A, Capozi A, Agostoni O. Regional right ventricular dysfunction in acute pulmonary embolism and right ventricular infarction. Eur J Echocardiogr 2005;6:11–4. 5. Piazza G. Submassive Pulmonary embolism. JAMA 2013;309: 171–80.
3
SUPPLEMENTARY DATA Supplementary data associated with this article can be found, in the online version, at http://dx.doi.org/10. 1016/j.jemermed.2014.01.032.
Streaming video: One brief real-time video clip that accompanies this article is available in streaming video at www.journals.elsevierhealth.com/periodicals/jem. Click on Video Clip 1.
