P868 Dissecting myocardium

Abstract

Abstract Introduction Incomplete rupture is a relatively uncommon type of free-wall rupture. It is found in 10% to 15% of total free-wall ruptures. Case report A 68-year-old male patient, heavy smoker, with medical history of diabetes mellitus and hypertension, had experienced an attack of acute retrosternal chest pain associated with dyspnea grade II-III one week before presentation. He presented to our facility complaining acute chest pain. Upon examination, the patient had stable vital signs and an unremarkable clinical examination except for distant heart sounds on auscultation. Electrocardiogram showed deep Q waves in V1 to V4 with residual ST segment elevation. Routine lab investigations were unremarkable including a negative troponin. A Chest X-ray showed an enlarged cardiac shadow. Echocardiography revealed a poor left ventricular systolic function due to an akinetic anterior wall and a dyskinetic apical cap containing a large highly mobile thread like mass which was suspected to be a thrombus. Coronary angiography revealed proximal 85% stenosis followed by mid segment total occlusion of the Left anterior descending (LAD) artery, proximal 75% stenosis of the left circumflex (LCX) artery and a tight lesion in the mid segment of the right coronary artery (RCA). The patient was diagnosed to have multi-vessel coronary artery disease and was maintained on medical treatment. Cardiac MRI was requested to detect myocardial viability before revascularization. Subsequently, cardiac magnetic resonance (CMR) revealed a dilated left ventricle with very poor systolic function, akinetic inferior wall, aneurysmally dilated apex and anterior wall with the same large highly mobile mass. Late gadolinium enhancement revealed scarred anterior, septal and inferior walls including all apical segments and surprisingly the mobile intra-ventricular mass also contained a scar tissue continuous with the anterior myocardial scar which means it is a part of the myocardium which was dissected or partially ruptured. Unfortunately, the patient suddenly experienced an attack of ventricular arrhythmia which was not resuscitated successfully. Conclusion Incomplete rupture is a rare type of free-wall rupture. It is thought that the infarcted myocardium wall is made weak in part by activation of metalloproteinases, which degrade the myocardial matrix. Structural weakness is associated with increased intra-cavitary pressure which predisposes the myocardial wall to rupture. Although Echocardiography is a good method of diagnosis but CMR is superior due to its high spatial resolution and good tissue characterization, plus the use of late gadolinium enhancement helps in identifying the location and the extent of prior infarctions guiding us to the next step in management. Abstract P868 Figure. Myocardial dissection with scarred flap