Focused cardiac ultrasound using a pocket-sized imaging device (V scan) is increasingly being used to screen patients in the emergency setting for structural heart disease. We describe a patient who presented with light-headedness and pallor with elevated high-sensitivity troponin T (hs-TnT) and was initially thought to have acute coronary syndrome. A screening focused cardiac ultrasound revealed a dilated right ventricle with normal left ventricular function, and a computerised tomography pulmonary angiogram (CTPA) demonstrated a large saddle pulmonary embolus. The case highlights the application and utility of focused cardiac ultrasound and provides an overview of its current role in the acute setting reinforced by current guidelines from the European Society of Cardiology.
Case report
A 74-year-old male with previous hypertension and myocardial infarction presented with light-headedness after walking down the stairs at home. He denied chest pain, but complained of shortness of breath on exertion. In the accident and emergency department he was noted to be pale and clammy. Initial observations were: regular pulse 88 bpm, blood pressure 127/81 mmHg, respiratory rate 20/min, and Sp02 95% (later consistently greater than 97%). He had stopped smoking aged 34 years.
On examination his chest was clear, the heart sounds were normal, the jugular venous pressure was not elevated and he had no peripheral oedema.
Initial electrocardiogram (ECG) showed normal sinus rhythm with a partial right bundle branch block, QRS duration 119 ms, and poor R-wave progression (figure 1).
Blood tests revealed an elevated N-terminal pro-brain natriuretic protein (NT-proBNP) 2,354 ng/L, and a rise in high-sensitivity troponin T (hs-TnT) from 85 to 287 ng/L at three hours. He was treated for an acute coronary syndrome with antiplatelets and fondaparinux, and transferred to the coronary care unit.
On review by the cardiology consultant, the symptom of light-headedness had resolved. He denied any chest pain or shortness of breath, and remained haemodynamically stable. The working diagnosis was an atypical presentation of acute coronary syndrome.
A screening focused cardiac ultrasound using a V scan revealed a dilated right ventricle with normal left ventricular systolic function. D-dimer was measured at 3,088 µg/L, and the patient was anticoagulated with low-molecular weight heparin. Computerised tomography pulmonary angiogram (CTPA) showed a saddle pulmonary embolism, with the thrombus extending bilaterally into the lobar pulmonary arteries (figure 2). The patient was commenced on warfarin. Subsequent ECG showed T-wave inversion in V1–2, III and AVF.
Discussion
The V scan is a pocket-sized ultrasound device that can provide 2D cardiac imaging/measurements and limited colour Doppler information (figure 3). This can provide important information to aid the diagnostic process, particularly in patients with non-specific symptoms and elevated cardiac biomarkers.1 Focused cardiac ultrasound is not equivalent to emergency echocardiography, and its limitations in practice must be noted. The European Society of Cardiology (ESC) has published recommendations for the use of emergency echocardiography,2 and also a separate position statement for the use of pocket-size devices.3 The two main indications for focused cardiac ultrasound using pocket-size devices are as a tool for fast initial screening in an emergency setting, and as a complement to a physical examination in the coronary and intensive care unit (table 1). Large pulmonary emboli may present with non-specific or vague symptoms, without evidence of significant hypoxia and without significant abnormality on the ECG. However, if large enough to cause right ventricular strain they can lead to elevated cardiac enzymes leading to a spurious diagnosis of acute coronary syndrome. Massive pulmonary embolism should always be considered in the differential diagnosis of patients with elevated cardiac enzymes, since the management of this life-threatening condition is very different to that used for acute coronary syndrome.
Use of focused cardiac ultrasound is becoming more frequent in the initial assessment of patients on the coronary care unit and the threshold for its use in the appropriate context should be low.
Key messages
- Focused cardiac ultrasound using a pocket-sized imaging device supplies valuable diagnostic information not provided by other bed-side diagnostic tests
- Massive pulmonary embolism may present with non-specific symptoms, and should always be considered in the differential diagnosis of patients with elevated cardiac biomarkers
- Pocket-sized imaging devices are useful for fast screening patients in the emergency setting or as a complement to physical examination
Conflict of interest
None declared.
Editors’ note
See also the editorial by Currie, and the article by Fabich et al. in this issue.
References
1. Prinz C, Voigt JU. Diagnostic accuracy of a hand-held ultrasound scanner in routine patients referred for echocardiography. J Am Soc Echocardiogr 2011;24:111–16. http://dx.doi.org/10.1016/j.echo.2010.10.017
2. Neskovic AN, Hagendorff A, Lancell P et al. Emergency echocardiography: the European Association of Cardiovascular Imaging recommendations. Eur Heart J Cardiovasc Imaging 2013;14:1–11. http://dx.doi.org/10.1093/ehjci/jes193
3. Sicari R, Galdferisi M, Voigt J et al. The use of pocket-size imaging devices: a position statement of the European Association of Echocardiology. Eur J Echocardiogr 2011;12:85–7. http://dx.doi.org/10.1093/ejechocard/jeq184
