A case of paradoxical air embolism in the coronary artery through a patent foramen ovale demonstrated by coronary CT angiography

Troponin-Positive Non-Obstructive Coronary Arteries and Myocardial Infarction with Non-Obstructive Coronary Arteries: Definition, Etiologies, and Role of CT and MR Imaging

In approximately 10% of patients with acute myocardial infarction (MI), angiography does not reveal an obstructive coronary stenosis. This is known as myocardial infarction with non-obstructive coronary arteries (MINOCA), which has complex and multifactorial causes. However, this term can be confusing and open to dual interpretation, because MINOCA is also used to describe patients with acute myocardial injury caused by ischemia-related myocardial necrosis. Therefore, with regards to this specific context of MINOCA, the generic term for MINOCA should be replaced with troponin-positive with non-obstructive coronary arteries (TpNOCA). The causes of TpNOCA can be subcategorized into epicardial coronary (causes of MINOCA), myocardial, and extracardiac disorders. Cardiac magnetic resonance imaging can confirm MI and differentiate various myocardial causes, while cardiac computed tomography is useful to diagnose the extracardiac causes.

Arterial Gas Emboli Secondary to Portal Venous Gas Diagnosed With Point-of-Care Ultrasound: Case Report and Literature Review

BACKGROUND

Portal venous gas (PVG) is a rarely observed clinical finding generally associated with intestinal ischemia. The proper clinical response to the finding of PVG depends somewhat on the setting in which it is observed. Here we describe a case in which extensive arterial gas emboli (AGE) were encountered during point-of-care ultrasound (POCUS) and subsequent computed tomography (CT) identified PVG secondary to gastric wall ischemia as the likely source.

CASE REPORT

A 69-year-old woman with history of metastatic colon cancer presented to the emergency department (ED) with altered mental status. On arrival, she was hypotensive, hypothermic, cachectic, and with abdominal distension. POCUS was performed to evaluate the source of the patient's hypotension, revealing the presence of PVG, as well as gas bubbles in all four chambers of the heart and the aorta. CT scan revealed gastric wall ischemia and confirmed the presence of significant air emboli throughout the portal venous system. Given the overall poor prognosis, the decision was made to forego further chemotherapy or surgery and the patient died later that week while under hospice care. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: AGE can occur in the setting of PVG. This may cause multi-organ failure by disrupting blood flow to organs, especially in patients with circulatory dysfunction, such as shock. Depending on the setting in which it is diagnosed, early detection of PVG may expedite earlier assessments of a patient's negative prognosis or initiation of attempted life-saving treatment. In this case report, we show that POCUS can be used to obtain an expedited diagnosis in a critically ill patient.

Association of the incidence of venous air embolism on coronary computed tomography angiography with the intravenous access route preparation process

Venous air embolism (VAE) can be observed in the right heart system on contrast-enhanced computed tomography (CT), following injection of contrast media with a power injector system. Although most VAEs are mostly asymptomatic, they may result in paradoxical air embolism (PAE).To evaluate whether the incidence of VAE on coronary CT angiography is associated with the process of preparation of the intravenous access route.We retrospectively evaluated 692 coronary CT examinations at 3 institutions. Trained CT nurses placed an intravenous cannula in the forearm. Tubes connected to the cannula were prepared in the following ways: A, using an interposed three-way cock and a 20-mL syringe filled with normal saline to collect air contamination in the tube; B, through direct connection to the power injector system without the interposed 3-way cock; and C, using an interposed three-way cock and a 100-mL normal saline drip infusion bottle system to keep the tube patent. The incidence and location of VAE and preparation of intravenous injection were assessed.The overall incidence of VAE was 55.3% (383/692), most frequently observed in the right atrium (81.5%, 312/383). Its incidence varied significantly across the 3 techniques (A: 21.6% (35/162), B: 63.2% (237/375) and C: 71.6% (111/155); P < .001). No patient demonstrated any symptom associated with VAE.Using a 3-way cock with syringe demonstrated the lowest incidence of VAE on coronary CT angiography. It is thus recommended to reduce potential complication risks related to intravenous contrast media injection.

A case of iatrogenic air bubbles in the left ventricle by coronary computed tomographic angiography

We report a case of asymptomatic iatrogenic air bubbles in the left ventricle observed by coronary computed tomographic angiography. Air bubbles are rarely found in the left ventricle and could prove fatal should they migrate to the brain or coronary arteries. We believe that the cause is micro air bubbles in the tubing system between the intravenous catheter and power injector.

Presence of gas in left ventricle due to infective endocarditis

Gas in myocardium is a rare manifestation of infective endocarditis caused by gas producing bacteria. We present a case of infective endocarditis caused by Citrobacter Koseri initially diagnosed by computed tomography and confirmed with transesophageal echocardiogram.

Paradoxical air embolism during percutaneous nephrolithotomy due to patent foramen ovale: Case report

Paradoxical air embolism is a very rare complication associated with percutaneous nephrolithotomy (PCNL). Incidence may be higher if patients also suffer from a septal heart defect. We report the case of a 76-year old male who presented for PCNL treatment of a right kidney lower calyceal calculus. During the procedure, the patient developed signs and symptoms consistent with that of air embolism. Intraoperative echocardiography confirmed the diagnosis. Subsequent intraoperative and postoperative medical management was carried out and the patient was discharged after recovery three days later. This case highlights the importance of a rare but potentially fatal complication of PCNL.