Primary Ventricular Fibrillation as The First Presentation of Aortic Dissection: A Case Report


 This study is about an infrequent first presentation of Aortic Dissection (AD), and it is primary Ventricular Fibrillation (VF). We present a 64-year-old woman with a history of hypertension who came with sudden retrosternal chest pain, dizziness, nausea, and vomiting. The patient suffered a cardiac arrest a few seconds after admission. Cardiopulmonary resuscitation (CPR) was done for her. An electrocardiogram (ECG) showed ST elevation that demonstrated acute anterior MI (Myocardial Infarction). Trans-thoracic echocardiography (echo) CT angiography demonstrated decreased left ventricular ejection fraction with normal LV size (LVEF=25%) and type A Stanford and type I DeBakey aortic dissection flap from root up to distal of abdominal Aorta. This is while the patient's first presentation was VF, and she had anterior MI, which is unusual for aortic dissection. Therefore, we must consider AD in patients with VF. We have to consider AD in anterior MI patients because of the contraindication of medication.


Introduction
Aortic Dissection (AD) is a rare, life-threatening condition that occurs when the damaged internal layer of Aorta results in blood owing throw the layers of Aorta. We cannot use antiplatelet and anticoagulant drugs because of the surgery situation in type A AD, but we have to use antiplatelet and anticoagulant drugs in Acute Myocardial Infarction (AMI). (1) In this case, Ventricular Fibrillation (VF) and ST-segment elevation guided us to AMI and the use of antiplatelet and anticoagulant drugs and interventional procedures like catheterization. However, like what was said, they should not be used in type A Stanford AD. Therefore there is a di cult situation in type A, AD patients, even in differential diagnosis and follow up.

Case Presentation
A 64-year-old woman with a history of hypertension was admitted to the emergency department of Imam Hossein Hospital in Shahroud at 9:00 AM with sudden retrosternal chest pain (burning and spreading to the arms), dizziness, nausea, and vomiting. Blood pressure (103/63 mm Hg), pulse rate (78 b/min), respiration rate (14 BPM), oxygen saturation (96%), blood sugar (180), and temperature (36°) were checked. Cardiac auscultation sounds were clear, S1 and S2 in cardiac auscultation were heard. Pulmonary auscultation was clear. She had no history of food or drug allergies and did not take any speci c medications or other medical conditions. She did not use any medicine for her hypertension and had uncontrolled hypertension.
The rst ECG was taken at 9:15, and it showed recurrent PVC. She suffered a cardiac arrest a few seconds after the rst ECG. Cardiopulmonary resuscitation (CPR) was done for her, and she received two shocks. The next ECG after successful CPR showed ST elevation in pericardial leads (V2-V6), and we found out that the arrest occurred in the eld of acute anterior MI. A 7.5 endotracheal tube was inserted, and she was connected to a ventilator. After 10 minutes of CPR, the rhythm became almost normal.
Routine laboratory tests were done for the patient, and you can see the results in the following table.
(  The patient's vital signs were controlled every ve minutes and the last one was at 6:45 PM blood pressure (114.53 mm Hg), pulse (59 b/min), respiratory rate (12 BPM), oxygen saturation (100%), temperature (37°). The patient needed surgery as soon as possible, and since our hospital did not have the necessary facilities for cardiovascular surgery, she was transferred to a center with these facilities.
Ethical approval was obtained from the patient and archived at Shahroud University of Medical Science Research Committee.

Discussion
AD symptoms may be similar to those of other heart disorders; AD is frequently confused with myocardial ischemia leading to a delayed or misdiagnosis, resulting in inappropriate treatment, including antithrombotic agents. (2) When a dissection ap extends proximally, it may impinge on the ori ce of one of the coronary arteries resulting in acute myocardial infarction (AMI) or ischemia. The dissection channel frequently propagates along the greater curvature of the Aorta and may compromise the Ostia of the arch vessels. Given its location on the greater curvature, the right coronary artery is particularly vulnerable to occlusion. This fact helps explain why most myocardial infarctions complicating aortic dissection are inferior in location. However, for patients with AMI, the missed diagnosis of AD could be catastrophic because the antiplatelet therapy and the cardiac catheterization, which are the therapeutic approaches for AMI, are exactly two absolute contraindications to AD treatment, as both of them can aggravate bleeding, broaden the range of the dissection, and even increase the risk of death. 10% of type B dissection patients have electrocardiographic signs of ischemia. So differential diagnosis should be performed on all patients to differentiate pain from AMI and AD. A normal ECG was seen in one-third of patients. ECG showed non-speci c ST-and T-wave changes in 42%, ischemic changes in 15%, and evidence of acute myocardial infarction in 5% of patients with an ascending aortic dissection. (7) The chest x-ray is insu cient to rule out or diagnose aortic dissection; however, it has been reported abnormal in 60%-90% of patients. (8) Both AD and AMI may have onset with acute chest pain, and it is sometimes di cult to diagnose them by symptoms, ECG changes, and/or cardiac biomarkers.
Our case was presented with ECG changes in ST-elevation and VF, which was similar to anterior MI. the physician did echocardiography to con rm his diagnosis and noticed aortic dissection, according to the witness. In contrast, for aortic dissection, we expect inferior MI to occur.

Conclusion
This study states that we have to consider Aortic dissection in patients with the presentation of arrhythmia, especially Ventricular Fibrillation (VF), even if Myocardial infarction has been demonstrated in them.

Declarations
Ethics approval and consent to participate Research committee of Shahroud University of Medical Sciences has approved this study.

Consent for publication
Written informed consent was obtained from the patient for their anonymized information to be published in this article.

Availability of data and materials
The datasets used during the current study are available from the corresponding author on reasonable request.   Video1.mov