Unmasking the Ventricular Pseudoaneurysm: A New Perspective with 4D Flow MRI (QF_FR_079)

A 58-year-old male chronic smoker with a history of recently diagnosed congestive heart failure and long-standing systemic arterial hypertension presented to the emergency department with acute gastroenteritis. No alarming signs were documented at the time of physical examination, so an outpatient follow-up was scheduled. Ten days later, the patient returned for re-evaluation, where resolution of the gastrointestinal symptoms was documented; an echocardiogram was performed due to the history already described, where an image suggestive of an aneurysm in the lateral wall of the left ventricle was documented, so that angiotomography (angio-CT) and cardiac magnetic resonance (CMR) were requested for further evaluation.

Diagnostic Techniques and Their Most Important Findings: Angio-CT shows a left ventricular pseudoaneurysm originating in the lateral wall, specifically the basal and middle thirds, with a neck of 67 x 62 mm and a volume of 463.1 ml. Hypodense images suggestive of thrombus adhering to the inner wall are observed.

CMR confirms the volume of the pseudoaneurysm and better delineates the thrombus with late enhancement (LGE) located in the mural contour with a thickness of 15 mm. Thinning and dyskinesia are observed in the basal and middle thirds of the lateral wall, with inferior akinesia and apical septal hypokinesia. Left ventricular ejection fraction (LVEF) of 7%, myocardial mass of 38 g, end-diastolic volume of 538 ml, and end-systolic volume of 500 ml.

Mild mitral regurgitation secondary to posteromedial papillary muscle retraction was observed. Late enhancement sequences after intravenous contrast show an ischemic pattern in the basal, medial and apical regions with transmural and subendocardial extension.

Evaluation with 4D Flow MRI: Allows detailed assessment of flow dynamics and pseudoaneurysm anatomy, identifying abnormal flow patterns, turbulence and ventricular hemodynamic changes.

Learning Points from this Case: Rare but deadly complication: Ventricular pseudoaneurysms are a rare complication of myocardial infarction with a high risk of rupture and mortality of up to 90%.

Difference from true aneurysms: Pseudoaneurysms lack myocardial layers and are composed only of fibrous and pericardial tissue, which increases the risk of rupture.

Risk factors: Include previous infarction, hypertension, age over 70 years, and late reperfusion.

Transmural infarct formation: Occurs when the weakened ventricular wall ruptures and bleeding is contained by the pericardium.

Diagnosis and Treatment: Early diagnosis and surgical correction are essential to reduce mortality.

Prognosis and Recurrence: There is a 17% recurrence rate after surgery, but the prognosis is similar to that of patients with infarction without rupture.