Acute myocardial infarction due to spontaneous, localized, acute dissection of the sinus of Valsalva detected by intravascular ultrasound and electrocardiogram-gated computed tomography

Abstract

A 58-year-old man was referred to our hospital because of chest pain. The 12-lead electrocardiogram (ECG) revealed ST-segment elevation in II, III, and a Vf with advanced heart block. Transthoracic echocardiography demonstrated aortic root dilatation at the sinus of Valsalva, moderate aortic regurgitation, and decreased wall motion in the inferior part of the left ventricle. Non-ECG-gated enhanced computed tomography (CT) did not reveal an aortic dissection. The patient underwent emergent coronary angiography, which revealed a severely narrowed ostium of the right coronary artery (RCA). Percutaneous coronary intervention (PCI) was performed under intravascular ultrasound (IVUS) guidance. IVUS images demonstrated an intimal flap extending from the aortic wall to the proximal RCA, suggesting that a periaortic hematoma in the false lumen compressed the ostium of the RCA, leading to acute myocardial infarction. To recover hemodynamic stability, the RCA ostium was stented. Subsequent ECG-gated enhanced CT clearly depicted the entry point and extension of the dissection localized within the sinus of Valsalva. The dissection likely involved the left main coronary artery and an emergent Bentall procedure was performed. Intraoperative findings confirmed an intimal tear and extension of the dissection. Thus, ECG-gated CT can clearly depict the entry site and extension of a dissection occurring in the localized area that cannot be detected by conventional CT.

Spontaneous Coronary Artery Dissection: Current State of the Science: A Scientific Statement From the American Heart Association

“…58,149,151 Poorly gated or nongated computed tomography angiography (such as computed tomography for pulmonary embolus) is inadequate for coronary artery assessment. 53,149,152,153 …”

Conservatively treated coronary malperfusion associated with acute type A dissection before aortic root replacement

“…When an ischemic change is suspected to be related to aortic dissection, ECG-gated cardiac MDCT should be performed before catheterization, because it is a non-invasive method for assessing the coronary arteries and can be performed quickly. ECG-gated cardiac MDCT reduces the severity of motion artifacts and makes it easier for the physician to assess the presence of an intimal tear in the aortic root and dissection extension into the coronary arteries [7][8][9][10]. When planning the surgical approach, it is important to assess the presence of aortic regurgitation, pericardial effusion, the extension of the dissection into major aortic branches, the location of entry and reentry sites, and the presence of thrombosis in the false lumen.…”

“…In such cases, valve-sparing root repair or complete root replacement with a valve conduit is considered preoperatively to be the best surgical approach. Notably, Ichihashi et al [10] also reported that ECG-gated MDCT is useful for assessing the extent of dissection and the localization of entry in patients with acute aortic dissection located within the sinus of Valsalva [10].…”

Localized Aortic Root Dissection with a Superior Mesenteric Artery Aneurysm

“… 1 ) Compared with non-ECG-gated CTA, ECG-gated CTA reduces motion artifacts and improves the accuracy of the diagnosis of an aortic dissection. 7 ) Although the routine and initial use of ECG-gated CTA is ideal to diagnose an aortic dissection, the increase in the patient’s exposure to radiation and the cost of the facilities may become issues that need to be solved. 8 ) Moreover, ECG-gated CTA is affected by arrhythmia.…”