Myocardial infarction associated with infective endocarditis: a case series

Embolic myocardial infarction with cardiac arrest as an initial manifestation of non-bacterial thrombotic endocarditis

Non-bacterial thrombotic endocarditis, characterised by sterile vegetations, is commonly caused by systemic lupus erythematosus and is known to be complicated with embolic cerebrovascular disease. Embolic myocardial infarction with non-bacterial thrombotic endocarditis is extremely rare. We report a case of ventricular fibrillation arrest from presumed coronary embolisation in non-bacterial thrombotic endocarditis. While there are no standardised guidelines on the management of embolic myocardial infarction in endocarditis, it requires a multidisciplinary approach unique for every encountered clinical scenario.

Myocardial infarction due to septic thromboembolism in chronic rheumatic heart disease

Chronic rheumatic heart disease (RHD) is the most troublesome complication of rheumatic fever. Extensive valvular scarring and ventricular remodeling due to pressure and volume overload occur in chronic RHD. Deformed valves are at potential risk for developing infective endocarditis (IE) with further systemic embolism. We hereby describe a case of a patient diagnosed with chronic rheumatic heart disease and severe ventricular dysfunction, planned for aortic valve replacement. The patient developed septic shock during a hospital stay. The autopsy revealed infective endocarditis in the aortic valve with septic thromboembolism in the peripheral branches of the coronary artery and early multifocal myocardial infarction changes.

Mechanisms of Coronary Ischemia in Women

PURPOSE OF REVIEW

Obstructive coronary artery disease is a major cause of ischemia in both men and women; however, women are more likely to present with ischemia in the setting of no obstructive coronary arteries (INOCA) and myocardial infarction with no obstructive coronary arteries (MINOCA), conditions that are associated with adverse cardiovascular prognosis despite absence of coronary stenosis. In this review, we focus on mechanisms of coronary ischemia that should be considered in the differential diagnosis when routine anatomic clinical investigation leads to the finding of non-obstructive coronary artery disease on coronary angiography in the setting of acute myocardial infarction.

RECENT FINDINGS

There are multiple mechanisms that contribute to MINOCA, including atherosclerotic plaque disruption, coronary artery spasm, coronary microvascular dysfunction (CMD), coronary embolism and/or thrombosis, and spontaneous coronary artery dissection. Non-coronary causes such as myocarditis or supply-demand mismatch should also be considered on the differential when there is an unexplained troponin elevation. Use of advanced imaging and diagnostic techniques to determine the underlying etiology of MINOCA is feasible and helpful, as this has the potential to guide management and secondary prevention. Failure to identify the underlying cause(s) may result in inappropriate treatment and inaccurate counseling to patients. MINOCA predominates in young women and is associated with a guarded prognosis. The diagnosis of MINOCA should prompt further investigation to determine the underlying cause of troponin elevation. Patients with INOCA and MINOCA are heterogeneous, and response to treatments can be variable. Large randomized controlled trials to determine longer-term optimal medical therapy for management of these conditions are under investigation.

ST-segment elevation myocardial infarction due to septic coronary embolism: a case report

Background 

Coronary artery embolism is an infrequent cause of type 2 myocardial infarction which can be due to arterial thromboembolism or septic embolism. While systemic embolization is one of the most acknowledged and threatened complications of infective endocarditis, coronary localization of the emboli causing acute myocardial infarction is exceedingly rare occurring in <1% of cases.

Case summary 

A 52-year-old man with a history of Bentall procedure and redo aortic valve replacement due to prosthetic degeneration (11 years prior to the current presentation) presented to the emergency department with high-grade fever and myalgias. Shortly after his arrival, he experienced typical chest pain and an electrocardiogram demonstrated signs of inferior ST-elevation myocardial infarction: coronary angiography showed a lesion of presumed embolic origin at the level of the mid-distal circumflex coronary artery which was treated with embolectomy. Transthoracic and transoesophageal echocardiography highlighted the presence of a periaortic abscess. The final diagnosis of infective endocarditis as the cause of septic coronary artery embolization was confirmed with a Positron Emission Tomography-Computed Tomography (PET-CT) exam and by the growth of Staphylococcus lugdunensis on repeated blood cultures. The patient underwent successful redo Bentall surgery the good outcome was confirmed at 1-month follow-up.

Discussion 

Type 2 myocardial infarction caused by coronary embolism is a rare presentation of infective endocarditis and requires a high level of suspicion for its diagnosis. Prosthetic heart valves are a predisposing factor for infective endocarditis: aortic root abscess requires surgery as it rarely regresses with antibiotic therapy.

Fatal Embolic ST-Elevation Myocardial Infarction Secondary to Healed-Phase Mitral Valve Infective Endocarditis

Embolic myocardial infarction (MI) caused by infective endocarditis (IE) is rare, but it is increasingly recognized as an important complication. This complication typically occurs in patients with aortic valve endocarditis during the acute phase of the infection. It is also known to have a high mortality rate; however, the best practice for its management is unclear owing to scarce available data. In addition, most cases of embolic acute MI (AMI) caused by IE are indirectly diagnosed with a combination of angiographic examination such as coronary angiography or cardiac computed tomography. Herein, we report a case of fatal embolic ST-elevation MI (STEMI) caused by mitral valve IE during the healed phase, which was clearly proven by the pathology findings.

Native Aortic and Tricuspid Valve Endocarditis Complicated by Embolic ST Elevation Myocardial Infarction

Acute myocardial infarction due to a coronary embolic event can occur as a complication of infective endocarditis in up to 2.9% of cases and can frequently be the presenting symptom. A 35-year-old female presented with 4 hours of typical chest pain and was found to have ST elevations in inferior leads as well as an elevated serum Troponin I of 8.29 ng/ml (normal: <0.06 ng/ml). Urgent cardiac catheterization revealed total occlusion of the right coronary artery without other coronary disease or collaterals. Following a failed attempt at thrombus extraction, a 3.0 × 38 mm bioabsorbable drug-eluting stent was placed. Echocardiography then revealed large mobile aortic valve vegetations with the largest measuring 1.4 × 1.7 cm, severe tricuspid regurgitation with a 1.1 × 0.5 cm mobile vegetation on the anterior leaflet along with a patent foramen ovale with right-to-left shunting. Blood cultures identified Enterococcus faecalis in 4 of 4 vials. The patient underwent urgent replacement of tricuspid and aortic valves as well as 6 weeks of IV antibiotics followed by chronic antibiotic suppression.