Fulminant myocarditis in a patient with severe coronary artery disease

Abstract

A 55-year-old man complaining of fever and exertional dyspnea was admitted for coronary angiography to differentiate between fulminant myocarditis and acute coronary syndrome. He had been treated for 17 years for angina pectoris. His electrocardiogram demonstrated ST segment changes in almost all leads. Cardiac catheterization demonstrated severe stenosis in the left descending artery, the diagonal branch, and the right coronary artery. Ultrasonography, however, revealed diffuse hypokinesis of the left ventricle and edematous wall thickening, suggesting fulminant myocarditis. This is the first report in which a patient with fulminant myocarditis with severe coronary artery disease was successfully treated with mechanical cardiopulmonary support, intensive pharmacological therapy, and staged coronary intervention procedures. Complicated coronary artery disease may delay the diagnosis of myocarditis and worsen the clinical outcome. Patients having fulminant myocarditis with coronary artery disease need careful diagnosis, and percutaneous cardiopulmonary support should be considered in the early clinical stage.

<Learning objective: Complicated coronary artery disease may delay the diagnosis of myocarditis and worsen the clinical outcome. It is considered safe to use percutaneous cardiopulmonary support for such patients in the early clinical stage. The present case was rescued with mechanical support in the acute phase of fulminant myocarditis and elective coronary angioplasty in the recovery phase.>

Introduction

Fulminant myocarditis is characterized by severe hemodynamic compromise requiring high-dose vasopressor support or mechanical circulatory support. The co-existence of coronary artery disease, however, can make the diagnosis of myocarditis more complicated and the cardiac function worse, resulting in a poor clinical outcome [1]. Therefore it is important to exclude the coexistence of coronary artery disease by emergency angiography when necessary. We report the case of a 55-year-old male, with severe ventricular dysfunction and heart failure, who was found to have coronary artery disease involving right and left coronary arteries and who underwent successful intensive supportive therapy for fulminant myocarditis and staged percutaneous transluminal coronary angioplasty.

Case report

A 55-year-old male had a 2-day prodrome of fever and mild chest pain. He was diagnosed as having effort angina pectoris 17 years earlier and received medication, although he refused coronary angiography. He had three coronary risk factors, hypertension, dyslipidemia, and obesity. Since he developed exertional dyspnea, he visited a local hospital. Because his electrocardiogram (ECG) demonstrated 1–2-mm ST elevation in II, III, aVF, aVR, V1–V3, and 1–2-mm ST depression in I, aVL, and V4–V6 (Fig. 1A), although his previous ECG was normal, acute coronary syndrome was suspected. Transthoracic echocardiography revealed severe, diffuse, left ventricular hypokinesis (ejection fraction 14%) without left ventricular dilation. However, the left ventricular wall was significantly thickened with edema [Fig. 2A, intraventricular septal wall (IVS) thickness 18 mm, posterior wall (PW) thickness 18 mm]. We could observe also minor pericardial effusion. He was admitted, and emergency cardiac catheterization and myocardial biopsy were performed. Coronary angiography revealed total occlusion of the distal right coronary artery with collateral flow from the left circumflex artery (Fig. 1B) and severe stenosis in the proximal segment of the left anterior descending artery and the first major diagonal branch (Fig. 1C). Left ventriculography showed severe diffuse left ventricular hypokinesis with elevated left ventricular end-diastolic pressure. An intra-aortic balloon pump (IABP) was inserted due to cardiogenic shock. Although angiographic findings suggested severe coronary artery disease, he was diagnosed as having fulminant myocarditis based on the echocardiographic findings and clinical course, and he was immediately transferred to our hospital for intensive treatment.

Fig. 1.

(A) Electrocardiogram on admission showing ST-T changes in almost all leads. (B) Right coronary angiogram on admission showing total occlusion in the distal segment of the right coronary artery (RCA) with collateral arteries. (C) Left coronary angiogram on admission showing 90% stenosis in the left anterior descending (LAD) artery and the first major diagonal branch (D1).

Fig. 2.

(A) Ultrasonography in the acute phase showing severely impaired left ventricular systolic function and edematous wall thickening in the intraventricular septal (IVS) wall and the left ventricular posterior wall (PW). (B) Ultrasonography before discharge showing recovery of left ventricular systolic function and the disappearance of left ventricular wall edema. Note the normal pulse-wave Doppler velocity in left ventricular outflow.

On admission, his blood pressure was 65/40 mmHg under IABP support, his pulse was 120 beats/min, and his temperature was 37.5 °C. He developed dyspnea and heart failure, which rapidly progressed to cardiogenic shock and required mechanical ventilation, percutaneous cardiopulmonary support (PCPS), and continuous hemodiafiltration (CHDF). With mechanical support, a 2 g/kg dose of immunoglobulin was administered intravenously over 48 h. Right ventricular endomyocardial biopsy revealed multiple necroses, degeneration of myocardial cells, and extensive infiltration of inflammatory cells, consistent with acute myocarditis. Creatine kinase and cardiac troponin T on admission were 938 IU/l (normal < 170 IU/l) and 2.28 (normal ≤ 0.10 ng/ml), respectively. The endomyocardial biopsy showed the infiltration of lymphocytes and necrosis of myocytes, consistent with lymphocytic myocarditis (Fig. 3).

Fig. 3.

Endomyocardial biopsy specimen on admission showing lymphocytic infiltrate and myocardial necrosis (hematoxylin and eosin, 200×).

The patient's clinical course was satisfactory: the PCPS was removed on the 5th day, and he was weaned off IABP and CHDF on the 6th day after admission. After his general condition improved, he underwent percutaneous coronary interventions to the proximal left anterior descending artery and the first major diagonal branch. Left ventricular wall motion and outflow were markedly improved (Fig. 2B, ejection fraction 69%), and wall swelling disappeared (Fig. 2B, IVS thickness 12 mm, PW thickness 11 mm) on the echocardiographic evaluation before discharge. The patient left our hospital without symptoms, approximately one month after admission.

Discussion

Myocarditis is clinically and pathologically defined as inflammation of the myocardium caused by infections, drug toxicity, or immunological reactions [2]. Fulminant myocarditis is characterized by severe hemodynamic compromise requiring high-dose vasopressor support or mechanical circulatory support. Clinical presentations of myocarditis range from nonspecific systemic symptoms including fever, myalgia, palpitations, and exertional dyspnea to fulminant hemodynamic collapse and sudden death. Thus, once fulminant myocarditis is suspected, immediate treatment, including intensive hemodynamic support and aggressive pharmacological intervention such as vasopressors and positive inotropic agents should be started, as in other patients with advanced heart failure due to profound left ventricular dysfunction. However, the incidence and prevalence of fulminant myocarditis remain unknown because of its rarity. A single-center study reported that the prevalence of fulminant myocarditis was 10.2% among patients with biopsy-proven myocarditis and 0.9% among patients with new-onset heart failure [3].

Fulminant myocarditis masquerading as an acute coronary syndrome has been often described [4]. Although the present patient had severe coronary artery stenosis, the diagnosis was fulminant myocarditis because of the clinical course, including symptoms of upper respiratory infection, unexplained new onset heart failure, and echocardiography findings including normal left ventricular cavity size and reversible left ventricular hypertrophy [2], [5]. A Japanese national survey reported that 8 (18.6%) of 43 cases with fulminant myocarditis were diagnosed as having an abnormal coronary artery [6]. However, it has been rarely reported that a patient with fulminant myocarditis had significant stenoses in multiple coronary vessels [1]. The co-existence of coronary artery disease can make the diagnosis of myocarditis more complicated and the cardiac function worse, resulting in a poor clinical outcome [1]. Furthermore, myocarditis itself can induce coronary vasospasm even in a normal coronary artery [7], which can worsen myocardial ischemia. Thus, it is important to exclude the coexistence of coronary artery disease by emergency angiography when necessary. When patients with myocarditis have severe coronary artery disease, such patients must be treated very carefully. The present case was rescued with mechanical support in the acute phase of myocarditis and elective coronary angioplasty in the recovery phase. Unexpectedly, this is, to the best of our knowledge, the first report that coronary atherosclerotic disease complicating fulminant myocarditis was treated successfully by staged coronary interventions. It is considered safe to use percutaneous cardiopulmonary support for such patients in the early clinical stage.

Conflict of interest

Authors declare that there is no conflict of interest.