Focal Myocardial Thinning

Differential considerations for focal myocardial thinning:

• Normal Variant: At apex of left ventricle.
• Old myocardial infarction: Thinning restricted to a coronary artery territory and consistent with ECG findings.
• Cardiac sarcoidosis: Most commonly in the septum.
• Muscular left ventricular diverticulum: Tiny crypts in the left ventricular wall that can be seen in normal patients or those with hypertrophic cardiomyopathy.
• Post myocarditis:
• Fibro-fatty replacement:
• Muscular dystrophy: In addition to skeletal muscle involvement, there nearly always is an associated cardiomyopathy in Duchenne or Becker muscular dystrophy.
• Primary aneurysm:
• Dilated phase hypertrophic cardiomyopathy:
• Complete left bundle branch block: Possibly due to redistribution of cardiac mass from chronic asynchronous electric activation.
• Arrhythmogenic right ventricular dysplasia:

References

• Prinzen FW, Cheriex EC, Delhaas T, van Oosterhout MF, Arts T, Wellens HJ, Reneman RS. Asymmetric thickness of the left ventricular wall resulting from asynchronous electric activation: a study in dogs with ventricular pacing and in patients with left bundle branch block. Am Heart J. 1995 Nov;130(5):1045-53.
• Srichai MB, Hecht EM, Kim DC, Jacobs JE. Ventricular diverticula on cardiac CT: more common than previously thought. AJR Am J Roentgenol. 2007 Jul;189(1):204-8.
• Yoshida N, Funabashi N, Uehara M, Yajima R, Kataoka A, Ueda M, Takaoka H, Komuro I. Differentiation of diagnosis and prognoses of non-coronary arterial primary myocardial diseases with left ventricular focal myocardial thinning evaluated by multislice computed tomography. Int J Cardiol. 2009 Nov 3.