Acute pulmonary embolism.
The echocardiogram shows an apical, four-chamber view. This patient
has a hyperdynamic, underfilled left ventricle (the chamber on the upper
right), and an enlarged right ventricle (chamber on the upper left).
The right ventricle is globally hypokinetic, with the exception of the
apex, which is hyperkinetic . This hyperkinetic apex is sometimes
referred to as an apical wink. This echocardiographic finding
(hypokinesia/akinesia in the mid-free right ventricular wall with
preserved apical kinesis) is commonly called McConnell’s sign.1
The right ventricle dilates and assumes a more spherical shape,
either as a direct response to pressure overload, or due to decreased
perfusion of the myocardium from the increased pressure. The mechanism
of preserved right ventricular apical function is unclear, possibly
related to being tethered to a hyperdynamic left ventricle and/or due
to relatively preserved perfusion to the RV apex. This finding was
initially thought to be highly specific for pulmonary embolism, but may
be present in other causes of acute right heart strain. Most notably,
McConnell’s sign may also be present in acute right ventricular
infarction.
Echocardiographic methods that may help differentiate acute pulmonary
embolism from RV infarction include estimation of the RV pressures from
tricuspid regurgitant jet (lower pressures in RV infarction) and time to
achieve peak blood velocity in the pulmonary artery (longer time to
achieve peak velocity in RV infarction). In this patient’s case, his
RVSP was estimated to be 48mmHg above the right atrial pressure.
Recognition of McConnell’s sign may be particularly useful in a
patient with suspected massive pulmonary embolism who is too unstable to
go to CT scan, and presumptive diagnosis of pulmonary embolism is
needed to justify thrombolytic therapy.
This patient had a saddle embolism seen on CT of chest, and was successfully treated with heparin.
References
- McConnell MV, Solomon SD, Rayan ME, et al.
Regional right ventricular dysfunction detected by echocardiography in
acute pulmonary embolism. Am J Cardiol 1996; 78:469-473
- Casazza F, Bongarzoni A, Capozi A, et al.
Regional right ventricular dysfunction in acute pulmonary embolism and
right ventricular infarction. Eur J Echocardiogr 2005; 6:11-14
