A Case of an Anomalous Hypertrophied Muscle Band in the Left Ventricle

Abstract

A hypertrophied muscle band (HMB) in the left ventricle (LV), which can be misinterpreted as apical hypertrophic cardiomyopathy, is a rare echocardiographic finding in a patient with normal LV wall thickness. Not only are symptoms produced, but changes in the electrocardiogram (ECG) are limited to the repolarization phase and show no progression even in a large HMB. Hence, we report a case of a 25-year-old woman who visited a local medical clinic due to epigastric discomfort in January 2007. The 24-hour Holter ECG showed multiple premature ventricular complexes. An HMB (3.23 × 10.8 cm) was observed on two-dimensional echocardiography that ran toward the interventricular septum (IVS) across the LV and divided the LV into apical and basal cavities at the apical one-third of the LV. Although LV wall thickness showed normal range, flow acceleration was observed between the HMB and IVS and revealed dagger-shaped with a high pressure gradient up to 30 mmHg in continuous wave Doppler examination. Circumferential band-like myocardial hypertrophy was observed at the LV apex on cardiac magnetic resonance imaging. Myocardial thinning and prominent trabeculae were present from the proximal to distal HMB. However, contractility was normal at the myocardial thinning site, regional wall motion abnormality was not observed in cine images. Focal fatty accumulation was evident at the base of the HMB. Coronary angiography revealed no significant stenosis, whereas left ventriculography showed septation at the apical one-third of the LV. The patient was discharged without any medication.

Protective Role of False Tendon in Subjects with Left Bundle Branch Block: A Virtual Population Study

“…Autopsy studies show that FTs comprise different tissue types including connective, conductive, and fibrous tissues, as well as blood vessels [ 1 – 5 ], which suggests that their presence is likely to intervene in the cardiac electrical conduction and more generally in the function of the heart. This is further supported by reports of isolated premature ventricular contractions [ 5 – 7 ], electrical activation re-entry [ 4 ], tachycardia [ 8 , 9 ], and electrocardiographic changes [ 10 – 14 ] in subject with FTs. So far, due to the complexity of the FTs and the challenges associated with their in vivo imaging, their exact significance, effects and possible risks to the human heart remain largely unclear [ 4 , 15 , 16 ].…”

Anomalous hypertrophied muscle band in LV mimicking LV mass

“…Patient is on follow-up with crucial vigilance regarding any rhythm disturbance without any medications currently. A hypertrophied muscle band in LV can sometimes mimic apical cardiomyopathy1 or LV mass. It is a rare echocardiographic finding in patients with normal LV wall thickness.…”

Unexplained Double‐Chambered Left Ventricle Associated with Contracting Right Ventricular Aneurysm and Right Atrial Enlargement

“…Lee et al . described a similar case of a 25‐year‐old female symptomatic for palpitations and chest discomfort.…”

“…In our case, the abnormal papillary muscle and the presence of several attachments to the ventricular wall could be consistent with a form of LVNC, even if imaging criteria were not fulfilled. 7 Lee et al 8 described a similar case of a 25year-old female symptomatic for palpitations and chest discomfort. In that case, a 12-lead ECG showed repolarization abnormalities and the echocardiogram showed a hypertrophied muscle band in the LV that ran toward the interventricular septum across the LV and divided the LV into apical and basal cavities with a mid-ventricular gradient associated.…”