Unstable Angina Caused by Honeycomb-Like Coronary Lesion Identified with Use of Optical Coherence Tomography

Abstract

A 67-year-old man had angina and dyspnea for several weeks during exercise and rest, and he came to our hospital for coronary angiography. He had mild ST-segment variability, without necrosis markers. Cardiac ultrasonograms revealed moderate mitral regurgitation, preserved ejection fraction, and a posterior-wall infarction scar despite no history of infarction. Coronary angiograms, which revealed no obvious culprit lesion, showed mild focal stenosis in the proximal right coronary artery, distal chronic occlusion of a small left circumflex coronary artery, and mild stenosis and haziness in the mid left anterior descending coronary artery (LAD) (Fig. 1). Suspecting thrombus in the mid LAD, we performed optical coherence tomography (OCT) (Fig. 2A). The OCT showed irregular honeycomb-like channels connecting the proximal and distal lumina, smooth appearance of the channels' inner surface and the separating septa, no visible fresh thrombus, and only a small plaque burden at the lesion site (Fig. 2B-E). We thought that the guidewire might have passed into a false lumen of a spontaneous dissection, so we advanced another guidewire, parallel to the first, to ensure entry into the distal true lumen. Given the patient's clinical instability, we performed angioplasty and implanted a bare-metal stent. Afterwards, OCT confirmed good distal flow without residual stenosis and showed a well-apposed stent, mild intima prolapse through the struts (Fig. 3A), and almost complete collapse of the parallel channels (Fig. 3B). Two years later, the patient was asymptomatic and well. Comment Lesions of this type were previously associated with recanalized thrombus. 1,2 They were compared with Swiss cheese, 1 or, when channels were spread over a larger area,

Diagnosis and treatment of angiographically unclear coronary lesions

“…There are hypotheses regarding dissection and inflammation as complications of atherosclerotic plaques as well as hypotheses regarding thrombus recanalization and neovascularization, tissue substitution after spontaneous dissection, and cardioembolic origin. [2][3][4]11 The literature indicates that such structures occur more often in men than women, at an average age of approximately 50 years, and in active smokers with an average of >20 cigarettes per day; these data are consistent with our case report. Smoking is considered to be the main trigger for the formation of such lesions because smoking causes endothelial dysfunction and increased prothrombotic activity of platelets.…”

“…All of these lesions are associated with the same or similar clinical symptoms. [2][3][4] The exact pathogenesis and epidemiological profile of non-atherosclerotic causes of coronary artery disease remain unclear, primarily because diagnosis is difficult. Although selective coronary angiography is the gold standard for the diagnosis of coronary lesions, this method does not provide all information about the pathophysiological mechanism underlying the formation of lesions of atherosclerotic and non-atherosclerotic origin.…”

Optical Coherence Tomography—OCT for Characterization of Non-Atherosclerotic Coronary Lesions in Acute Coronary Syndromes

“…The most prevalent coronary lesions are represented by the atherosclerotic plaques, in more than 85% of cases [ 1 ], but there are several other non-atherosclerotic lesions such as spontaneous coronary artery dissection and/or hematoma [ 8 , 9 ] and spontaneous recanalization of coronary thrombus [ 10 , 11 ], which are less common, approximately 5% of cases [ 1 ], but with similar clinical manifestations as well as complications. There are insufficient data regarding the pathological mechanism, true prevalence and optimal treatment of these kind of coronary lesions.…”

Distinctive Morphological Patterns of Complicated Coronary Plaques in Acute Coronary Syndromes: Insights from an Optical Coherence Tomography Study

“…By means of different backscattering and attenuation properties, each tissue component offers a specific OCT image. OCT provides invaluable insights in the setting of ACS [ 3 , 8 , 9 , 10 , 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 ] by allowing the exclusion of non-atherosclerotic causes [ 9 , 10 , 11 ] as well as defining the vulnerable plaque by evaluating the fibrous cap thickness and degree of macrophage infiltration [ 4 ]. Equally important, it can assess the culprit atherosclerotic lesions, with its favorable ability in detecting plaque erosion (PE), plaque rupture (PR) [ 21 ], or due to adequate calcium penetration, the calcified nodule (CN) [ 22 ].…”