A 57-year-old Middle Eastern woman presented to the emergencydepartment(ED)withleftarmandchestdiscomfortwhichdevelopedwhile driving her car. The discomfort lasted for a few minutes andresolved spontaneously. Past medical history was remarkable forknown LVH by ECG, severe concentric LVH by echocardiography andno coronary heart disease risk factors. ECG in the ED showed LVH andST segment depression in leads V4 through V6 and was unchangedfrom prior ECG done 1 year before. Serum troponin I was elevated at0.16 ng/ml (normal b0.05 ng/ml). Based on the clinical history,abnormal ECG and elevated troponin levels, the ED physicianconsidered the diagnosis of an acute coronary syndrome, adminis-teredaspirinandclopidogrelandrecommendedadmissionforfurtherobservation and management. Cardiology consultation was thensought in the ED, and in view of previously known diagnosis ofhypertrophic cardiomyopathy, immediate coronary CT angiography(CCTA) was recommended to rule out obstructive coronary arterydisease.Low dose CCTA (4.9 mSv) was performed using a 64 slice dual-source CT scanner (Somatom, Siemens Medical Solutions, Forchheim,Germany).CCTArevealednoevidenceforcoronaryplaqueorstenosis.Despite the positive troponin and the abnormal ECG, a diagnosis ofacute coronary syndrome was excluded, and the patient wasdischarged from the ED.Non-coronary assessment of the CCTA confirmed severe asym-metric septal hypertrophy and demonstrated an unusual finding ofthree thin crypts in the left ventricle. The largest crypt was 12 mm inlength in the superior mid septum at the junction of the left and rightventricles with a 2 mm separation from the right ventricle (Fig. 1 a