Coronary Sinus Flow Is Reduced and Recovered With Time in Viral Myocarditis Mimicking Acute Coronary Syndrome

Abstract

A Transthoracic Doppler Echocardiographic Studyhe complete evaluation of acute myocarditis is very complex and includes the history, physical examination, blood work, echocardiography, coronary angiography, and endomyocardial biopsy. 1,2 The current histopathologic criteria for myocarditis (the Dallas criteria) require an inflammatory infiltrate and associated myocyte necrosis or damage that is not characteristic of an ischemic event. 3 However, the clinical presentation of myocarditis often mimics acute coronary syndrome. Whether abnormal myocardial perfusion is accompanied by myocarditis despite normal coronary angiographic findings remains unknown.The coronary sinus is the major venous collection system for the myocardial perfusion, 4,5 ORIGINAL RESEARCHObjectives-The clinical presentation of myocarditis often mimics acute coronary syndrome. Coronary sinus flow has been used for detection of the presence of myocardial ischemia. Whether myocarditis is associated with changes in coronary sinus flow remains unknown. The aim of this study was to assess coronary sinus flow at the onset and follow-up of myocarditis mimicking acute coronary syndrome using transthoracic Doppler echocardiography (TTE).Methods-Sixty-four patients with clinically diagnosed viral myocarditis mimicking acute coronary syndrome underwent TTE on days 3, 7, 30, 90, 180, and 360 after onset. Coronary sinus flow was compared among different points in time.Results-Compared to healthy participants, all patients with myocarditis had a larger cardiac size, reduced cardiac function, and electrocardiographic and myocardial enzyme abnormalities on days 3 and 7 days (P < .01; P < .05). They later had gradual restoration to normal levels. On days 3 and 7, the coronary sinus flow in patients with myocarditis was extremely lower than that in healthy participants (about one-tenth), although coronary angiography revealed unobstructed arteries. On days 30, 90, 180, and 360, the coronary sinus flow had been increasing; however, it was still far less than that in healthy participants (P < .01).Conclusions-Coronary sinus flow depicted by TTE is reduced but recovers with time in viral myocarditis mimicking acute coronary syndrome, which is a useful indicator in the follow-up of this type of myocarditis.

The role of echocardiography in acute viral myocarditis

“…Most importantly, these patients need closer monitoring and should be managed in a high-care or cardiac-care setting. 1 Diagnosis of acute viral myocarditis is based on the presenting symptoms, elevated cardiac markers suggestive of myocardial necrosis, and electrocardiographic and echocardiographic changes. Although a wide range of diagnostic tests may be warranted when initially evaluating these patients, conventional echocardiography remains a crucial imaging modality to exclude other underlying cardiac diseases, to evaluate cardiac chamber size, wall thickness, ventricular function and presence of pericardial collections, to differentiate fulminant from acute myocarditis, and to help guide the patient's management.…”

Perioperative Ultrasound Flow Evaluation in Grafts and Native Vessel during CABG

“…Currently, there are no TTE-based diagnostic criteria for Ischemic Heart Disease of follow-up. Nor pre or nor post, but there are publications that describe TTE as a screening method for Coronary Artery Disease in isolated populations [36][37][38]. Quantifications of CS blood flow changes after CABG can be performed using Echocardiography [39][40][41].…”

Reversible impairment of coronary flow reserve in acute myocarditis

“…The vascular tone of coronary microvessels is physiologically regulated by myogenic, neural, metabolic, and endothelial mechanisms according to local demands . Myocardial inflammation interferes with this precisely regulated system and induces endothelial dysfunction and microcirculatory disturbances which lead to a reduced tissue perfusion and myocardial ischemia . Experimental studies have demonstrated that acute myocarditis is associated with capillary damage, microvascular luminal narrowing, and microvascular spasm …”