Diagnosis of Acute Mitral Valve Insufficiency Using Emergency Bedside Echocardiography

An 83-year-old female with a history of hypertension and diabetes presented to the emergency department with 10 days of progressive dyspnea on exertion and new orthopnea. She also reported symmetric leg swelling in the past week, but denied recent fevers, cough, or upper respiratory infection symptoms. Although she did report mild chest discomfort several weeks previously, this had resolved. There was no history of congestive heart failure or known coronary artery disease.

Her initial vital signs were as follows: pulse 69 beats/min, respiratory rate 22 breaths/min, peripheral oxygen saturation 85% on room air and 92% on 2 L of oxygen via nasal cannula, blood pressure 151/71 mm Hg, and temperature 98.7°F. She appeared dyspneic, speaking in short sentences. Physical exam revealed jugular vein distention, bibasilar crackles, trace bilateral pedal edema, and a systolic murmur of which the patient had no previous knowledge. The electrocardiogram demonstrated normal sinus rhythm without ischemic changes. Bedside thoracic ultrasound performed by the emergency medicine attending and resident showed numerous comet tail artifacts consistent with pulmonary edema (Figure 1 and Video Clip S1, available as supporting information in the online version of this paper). Bilateral pleural effusions were also noted (Figure 2 and Video Clip S2, available as supporting information in the online version of this paper). These findings were confirmed by chest x-ray. Ultrasound in the subcostal long-axis position demonstrated a dilated inferior vena cava without respiratory variation, concerning for an elevated central venous pressure (Figure 3 and Video Clip S3, available as supporting information in the online version of this paper). Bedside echocardiography by the emergency physicians revealed an enlarged left atrium and significant mitral regurgitation (Figures 4 and 5 and Video Clip S4, available as supporting information in the online version of this paper). The b-type natriuretic peptide was 1662 pg/mL, and the troponin level was not elevated. Taken together, these findings suggested new congestive heart failure, possibly due to acute mitral valve insufficiency. The patient was admitted with these diagnoses. A formal echocardiogram performed the next day confirmed severe mitral regurgitation due to flail posterior mitral leaflet secondary to ruptured chordae. She underwent urgent mitral valve replacement annuloplasty and was discharged 3 weeks later.

Figure 1.  Transthoracic ultrasound shows numerous comet tail artifacts indicative of pulmonary edema.

Figure 2.  Ultrasound along the right midaxillary line shows the lung tip surrounded by a large pleural effusion.

Figure 3.  A subcostal long axis view demonstrates a dilated inferior vena cava with minimal respiratory variation. IVC = inferior vena cava; RA = right atrium.

Figure 4.  An enlarged left atrium is visualized in the apical four-chamber view. LA = left atrium; LV = left ventricle; RA = right atrium; RV = right ventricle.

Figure 5.  Color flow demonstrates a regurgitant jet from the left ventricle into the left atrium with each beat. LA = left atrium; LV = left ventricle.

Limited bedside echocardiography by emergency physicians has become increasingly commonplace. Initially used only to determine presence or absence of pericardial effusion, many now advocate its use in a wide range of other situations including new congestive heart failure. Such use by emergency physicians may uncover new structural or functional abnormalities, including valvular incompetence, acute cardiomyopathies, or proximal aortic dissection that ultimately aid the patient by hastening definitive treatment.