The "heart appearance" sign in bilateral pontine infarction.

BACKGROUND

Although rarely seen, bilateral anteromedial infarction of the pons demonstrates the characteristic "heart appearance" sign on magnetic resonance imaging (MRI). This sign has hitherto been described in only 2 patients before this article. This typical pattern can be attributed to atherosclerotic or thrombotic involvement of bilateral paramedian and short circumferential pontine arteries supplying the anteromedial pons.

METHODS AND RESULTS

A 60-year-old man, a known patient of primary hypertension and diabetes mellitus, presented with a posterior circulation stroke. Urgent computerized tomography and MRI revealed a "heart-shaped" area of acute infarction in the anteromedian mid-pons. A few scattered infarcts were also noted in the posterior and inferior part of the right cerebellar hemisphere. The basilar artery appeared normal with preserved flow void on MRI, and there were no signs of hemorrhage. These findings were consistent with acute nonhemorrhagic infarcts involving bilateral paramedian and short circumferential pontine arteries and the right posterior inferior cerebellar artery. A repeat MRI performed after a week disclosed hemorrhagic transformation and enhancement of the pontine infarction. The basilar artery appeared normal on magnetic resonance angiography.

CONCLUSIONS

Recognizing the "heart appearance" sign in a stroke-like episode may be helpful in differentiating bilateral anteromedial pontine infarction from other pathologic processes involving the pons.