Nonatherosclerotic causes of coronary artery narrowing--Part I

Anatomical reconstruction of proximal coronary artery stenosis in children

OBJECTIVES

Timing and method of surgical reconstruction for non-sclerotic proximal coronary artery stenosis, occuring de-novo or post coronary artery transfer, are evolving. We have pursued a technique of anatomical reconstruction of ostial and short segment proximal coronary artery stenosis and atresia in children, using patch plasty or interposition vein graft. Herein, we discuss the medium- to long-term outcome.

METHODS

Nine consecutive children undergoing ten left main coronary artery reconstructions using autologous great saphenous vein patch (n = 4), autologous pericardium (n = 4), xenopericardium (n = 1) or great saphenous vein interposition graft (n = 1) were retrospectively analysed. Complementary wedge resection of the stenotic coronary ostium was performed in chronic cases.

RESULTS

The aetiology of coronary artery stenosis was post arterial switch operation (n = 6), Takayasu`s arteritis (n = 1), idiopathic left main coronary artery atresia (n = 1) and anomalous origin of the left coronary artery from the pulmonary artery (n = 1). Median age and weight at operation were 0.15 (range 0.01-13.1) years and 4.4 (range 3 -13.1) kilograms, respectively. Survival was 100% at median follow-up of 12.6 (range 1-19.2) years. All patients showed normal left ventricular ejection fraction on transthoracic echocardiogram. In one patient, kinking of the proximal left circumflex artery resulted in non-significant obstruction. In all other cases, follow-up catheter angiography revealed unobstructed coronary arteries. Cardiac magnetic resonance tomography showed no significant perfusion deficit in any child.

CONCLUSIONS

Anatomical reconstruction of the proximal left coronary artery using autologous saphenous vein may allow optimal restoration of physiological coronary blood flow, keeping the option of future coronary bypass operation open.

Coronary artery vasculitis: a review of current literature

Cardiac vasculitis is recognized as a heterogeneous disease process with a wide spectrum of manifestations including pericarditis, myocarditis, valvular heart disease and less frequently, coronary artery vasculitis (CAV). CAV encompasses an emerging field of diseases which differ from conventional atherosclerotic disease and have a proclivity for the younger population groups. CAV portends multiple complications including the development of coronary artery aneurysms, coronary stenotic lesions, and thrombosis, all which may result in acute coronary syndromes. There are several aetiologies for CAV; with Kawasaki's disease, Takayasu's arteritis, Polyarteritis Nodosa, and Giant-Cell Arteritis more frequently described clinically, and in literature. There is a growing role for multi-modality imaging in assisting the diagnostic process; including transthoracic echocardiography, cardiac magnetic resonance imaging, computed tomography coronary angiography, fluorodeoxyglucose-positron emission tomography and conventional coronary angiogram with intravascular ultrasound. Whilst the treatment paradigms fundamentally vary between different aetiologies, there are overlaps with pharmacological regimes in immunosuppressive agents and anti-platelet therapies. Interventional and surgical management are is a consideration in select populations groups, within a multi-disciplinary context. Further large-scale studies are required to better appropriately outline management protocols in this niche population.

CAD-RADS: Pushing the Limits

Coronary CT angiography is now established as the first-line diagnostic imaging test to exclude coronary artery disease (CAD) in the population at low to intermediate risk. Wide variability exists in both the reporting of coronary CT angiography and the interpretation of these reports by referring physicians. The CAD Reporting and Data System (CAD-RADS) is sponsored by multiple societies and is a collaborative effort to provide standard classification of CAD, which is then integrated into patient clinical care. The main goals of the CAD-RADS are to decrease variability among readers; enhance communication between interpreting and referring clinicians, allowing collaborative determination of the best course of patient care; and generate consistent data for auditing, data mining, quality improvement, research, and education. There are several scenarios in which the CAD-RADS guidelines are ambiguous or do not provide definite recommendations for further management of CAD. The authors discuss the CAD-RADS categories and modifiers, highlight a variety of complex or ambiguous scenarios, and provide recommendations for managing these scenarios. Online supplemental material is available for this article. ^©RSNA, 2020 See discussion on this article by Aviram and Wolak.

Sudden unexpected death due to coronary thrombosis associated with isolated necrotizing vasculitis in the coronary arteries of a young adult

Coronary arteritis is an uncommon cause of sudden death in non-atherosclerotic coronary diseases, and is mostly associated with systemic vasculitis or systemic autoimmune diseases; therefore, sudden death due to isolated coronary arteritis rarely occurs. The case described in this report is that of a 34-year-old man with no significant personal medical history who died suddenly after presenting with nausea. Postmortem examination revealed a significant infiltration of lymphocytes predominantly on the adventitia and periadventitial tissues of the coronary arteries in the epicardium. The lymphocytic infiltrate partially extended to the thickened intima with fibrosis, destructing the media and internal elastic lamina, and the lumen was occluded by a thrombus in the left main stem and left anterior descending branch. The arterial walls exhibited focal fibrinoid necrosis with regression in the intima and fibrous scars with angiogenesis in the media and adventitia. Focal myocardial infarction was detected in the left ventricle as a fibrotic change of the myocardium. No findings associated with vasculitis were discerned in the aorta, other peripheral arteries, or major organs. Laboratory tests of postmortem blood samples returned negative results for antinuclear antibodies, cryoglobulin, immunoglobulin G4, and cytoplasmic anti-neutrophil cytoplasmic antibodies for myeloperoxidase and proteinase 3. These autopsy findings suggest that the sudden death was caused by isolated necrotizing vasculitis that is assumed to be polyarteritis nodosa localized at the coronary arteries. However, pathological characteristics may not be exactly the same between isolated necrotizing vasculitis in the coronary arteries and polyarteritis nodosa.

Sudden Death Due to Coronary Arteritis

We report the case of a middle-aged man, without medical history, who suddenly died at his workplace. The autopsy highlighted a pathological heart macroscopically, with multiple small white areas on the left myocardium. Coronary dissection revealed a pseudotumoural fibromyxoid aspect within the anterior interventricular artery (AIVA) and the left main coronary trunk, including reduction in their diameter with tight stenosis. Microscopic examination of these arteries showed fibroinflammatory wall destruction. In the left myocardium, there were multiple focal ischemic areas at different stages of recovery. Our case is an illustration of primary ischemic heart disease due to coronary arteritis, with a pseudotumoural presentation, which was revealed by sudden death. We discuss the cause of death and the etiological diagnosis preceding coronary arteritis.

Anomalous origin of coronary artery: taxonomy and clinical implication

OBJECTIVE

Anomalous origin of coronary artery is uncommon. The taxonomies of anomalous origin of coronary artery are inconsistent and complex. Conceptual and therapeutic debates remain. The aim of the present study is to reappraise the concept of anomalous origin of coronary artery and to discuss the potential hazards and treatment rationale of this anomaly on basis of literature review.

METHODS

A comprehensive literature review was made in terms of the taxonomies including "simple", "multiple" and "complex" types of anomalous origin of coronary artery.

RESULTS

Anomalous origin of coronary artery can be simply categorized according to the ectopically originated coronary artery. There are a couple of complex anatomical variants: "multiple" type, involving more than one coronary artery or branch, which can be subdivided into 2 subtypes, A) more than one coronary arteries or branches arising from one place; and B) two coronary arteries/branches arising from separate ectopic sites; and "complex" type, associated with acquired heart disease, or congenital heart defects.

CONCLUSION

Sudden cardiac death in anomalous origin of coronary artery is associated with the anatomical features including abnormal coursing, acute angle take-off and ostial abnormalities. Atherosclerosis is prone to be in the right-sided ectopic and retroaortic coursing coronary artery. Surgical treatment is a definitive therapy. Simple coronary artery bypass grafting is not recommended due to the potential hazards of coronary steal phenomenon and poor patency of mammary arterial grafts, and modified maneuvers such as coronary ostial reimplantation, impinged coronary segment unroofing and coronary stent deployment are advocated instead.

ST-segment elevation in non-atherosclerotic coronaries: a brief overview

The most common, clinically significant cause of ST elevation is an angiographically demonstrable occlusive disease due to atherosclerotic changes in coronary artery. Often, a patient presenting with non-specific complaints and ST-segment elevation on the electrocardiogram, is sent for a cardiac catheterization only to see no luminal stenosis on the angiogram. This clinical review is intended to inform emergency medicine physicians and internists about the conditions in which ST-segment elevation is accompanied with no atherosclerotic lesion on coronary angiography. These situations make a diverse array of conditions ranging from anomalous coronaries to anatomically normal coronaries with varied degrees of myocardial injury. These conditions are briefly reviewed in this article.

Differential diagnosis of non-atherosclerotic left main coronary artery stenosis

A left main coronary artery (LMCA) stenosis without any atherosclerotic changes elsewhere in the coronary artery tree is a rare finding, and some uncommon reasons for luminal narrowing should be considered. An unusual case of non-atherosclerotic LMCA stenosis is reported.A middle-aged patient presented with acute myocardial infarction. An immediate coronary angiography was ordered and revealed a subtotal mid LMCA stenosis. A drug-eluting stent was successfully implanted in the LMCA.Operative revascularisation was recommended. Routine surgery was performed and surprisingly revealed an extended mass of a mediastinal tumour surrounding the aortic root. Histopathological examination of the tumour revealed a poorly differentiated squamous cell carcinoma.Postoperatively, the patient was treated with chemotherapy (carboplatin and docetaxel). Five years after the first admission to our hospital, the patient died as a result of ventricular fibrillation.The differential diagnosis of non-atherosclerotic LMCA stenoses is discussed.