Recurrent acute myocardial infarction associated with calcified pseudoaneurysm: A case analysis

Abstract

Left ventricular pseudoaneurysm (LVP), a rare but life-threatening complication following acute myocardial infarction (AMI), has an incidence of approximately 0.5% and a high mortality rate due to its significant risk of rupture. Early detection and timely surgical intervention are crucial. The diagnosis of LVP can be effectively achieved through various imaging modalities, including transthoracic echocardiography, cardiac magnetic resonance imaging, computed tomography angiography, and left ventriculography. However, determining the optimal therapeutic strategy requires a comprehensive multidisciplinary discussion approach and individualized consideration. This report presents a challenging case of a patient who experienced recurrent AMI 25 years after the initial event, with an incidental discovery of a calcified LVP. The distinctive features of this case include the long-term presence of a calcified pseudoaneurysm without rupture and the successful management strategy employed following the recurrent AMI.

Case report

A male patient in his early 70s presented to the emergency department of Gansu Provincial People’s Hospital in June 2024 with a sudden onset of chest tightness and palpitations that had persisted for 11 hours. Twenty-five years earlier, he had been diagnosed with an acute inferior ST-segment elevation myocardial infarction (STEMI) at a county-level hospital. At that time, he underwent thrombolytic therapy, followed by coronary angiography (CAG), which revealed the following findings: a normal left main trunk, atherosclerotic plaques in the left anterior descending artery (LAD), 70% stenosis in the proximal circumflex artery (LCX), 80% stenosis in the mid-distal right coronary artery (RCA), and subtotal occlusion of the left posterior descending artery. The patient subsequently underwent percutaneous transluminal coronary angioplasty of the RCA and remained asymptomatic with regular medication thereafter. Eleven hours prior to admission, the patient presented to a local hospital with acute onset of chest tightness and palpitations. The initial electrocardiogram (ECG) revealed ventricular tachycardia (Figure 1). Sinus rhythm was restored after two synchronized cardioversion attempts at 200 J. A subsequent ECG showed acute inferior STEMI (Figure 2). Emergency CAG revealed total occlusion of both the mid-RCA and mid-LCX, along with diffuse severe stenosis in the proximal to mid-LAD. Given the patient’s critical condition, he was transferred to our tertiary center for advanced management.

Figure 1.

Ventricular tachycardia.

Figure 2.

Acute inferior STEMI. STEMI: ST-segment elevation myocardial infarction.

On admission, the patient’s vital signs were stable, and the cardiopulmonary examination revealed no significant abnormalities. Serial cardiac enzyme tests showed dynamic changes consistent with acute myocardial infarction (AMI). A repeat ECG demonstrated a reduction in the previously elevated ST-segment in the inferior leads (Figure 3). Transthoracic echocardiography (TTE) revealed a pseudoaneurysm measuring 10 × 11 mm in the mid-posterior wall of the left ventricle, accompanied by reduced left ventricular systolic function (35%) (Figure 4). Subsequent contrast-enhanced cardiac magnetic resonance imaging (MRI) indicated thinning of the left ventricular lateral wall and adjacent inferior wall with delayed gadolinium enhancement. Additionally, localized bulging of the inferolateral wall with paradoxical motion was observed (Figure 5). Following multidisciplinary team discussion, surgical coronary artery bypass grafting and left ventricular pseudoaneurysm (LVP) repair were recommended. However, the patient and their family declined invasive surgery. As a result, the decision was made to proceed with percutaneous coronary intervention (PCI). During the procedure, a calcified mass measuring 10 × 10 mm was observed within the cardiac silhouette. Balloon angioplasty was performed on the mid-RCA. However, advancing the guidewire through the left ventricular posterior branch was difficult due to the chronic nature of the occlusion and the presence of collateral circulation. Despite these difficulties, a stent was successfully placed in the LAD (Figure 6). After the procedure, the patient’s condition remained stable. They adhered to the prescribed medication regimen and, at the 3-month follow-up, the patient continued to show good clinical progress. We will maintain close follow-up of the patient’s condition through regular assessments. One year after the procedure, CAG and cardiac MRI will be performed to comprehensively evaluate the structural stability of the LVP and confirm the long-term efficacy of the conservative treatment approach.

Figure 3.

Marked resolution of ST-segment elevation was observed in the inferior leads.

Figure 4.

TTE revealed a pseudoaneurysm measuring 10 × 11 mm in the mid-posterior wall of the left ventricle. TTE: transthoracic echocardiography.

Figure 5.

Cardiac MRI with contrast enhancement demonstrates thinning of the left ventricular lateral wall and adjacent inferior wall with delayed enhancement and localized aneurysmal bulging with dyskinesia in the inferolateral wall. MRI: magnetic resonance imaging.

Figure 6.

Balloon angioplasty of the mid-RCA and stent implantation in the LAD. RCA: right coronary artery; LAD: left anterior descending artery.

Discussion

LVP is a rare but potentially fatal mechanical complication of AMI. It is characterized by rupture of the left ventricular wall, with containment by the pericardium, thrombus, or scar tissue. ¹ It most commonly occurs following AMI, cardiac surgery, and interventional procedures. Additionally, trauma, infection, and certain connective tissue diseases can also contribute to its formation. ² Although the incidence of LVP after myocardial infarction is relatively low, at approximately 0.2%–0.3%, the risk of pseudoaneurysm rupture poses a significant threat, potentially leading to acute cardiac tamponade and sudden death. ³ Some patients may be asymptomatic, with LVP being incidentally detected during echocardiography or other examinations. ⁴ In this case, the patient experienced an acute inferior myocardial infarction 25 years ago and underwent RCA balloon angioplasty but did not receive subsequent cardiac follow-up. The patient was readmitted due to acute inferior STEMI and ventricular tachycardia, during which a left ventricular posterior wall pseudoaneurysm (13 × 13 mm) was incidentally identified. This case highlights the critical importance of regular cardiac examinations in post-AMI patients to detect and manage potential complications such as LVP in a timely manner.

Previous studies have identified traditional risk factors for LVP, including advanced age, female gender, hypertension, inferior and lateral myocardial infarction, and delayed reperfusion following infarction. ⁵ In this case, the patient’s risk factors included advanced age and a history of myocardial infarction, aligning with those reported in the literature. The diagnosis of LVP relies on multimodal imaging techniques, including TTE, cardiac magnetic resonance imaging (CMRI), computed tomography angiography, cardiac catheterization, and left ventriculography. ⁶ While cardiac catheterization and left ventriculography are considered the gold standards, CMRI is increasingly favored as a non-invasive modality due to its ability to characterize normal and abnormal myocardium, thrombus, and pericardium. ⁷ In this case, the patient’s LVP was incidentally detected via TTE, and subsequent CMRI provided a detailed evaluation of the aneurysm’s size, location, and the presence of thrombus or calcification. According to the literature,^8,9 LVP typically forms within 3–14 days following AMI. However, some studies suggest that its formation can be delayed for up to 12 months post-AMI, with approximately one-third of pseudoaneurysms occurring approximately 2 weeks after infarction. In this case, the patient experienced an acute inferior myocardial infarction 25 years ago and underwent RCA balloon angioplasty but did not receive subsequent cardiac follow-up. Given the calcified and chronic nature of the LVP, it is hypothesized that the pseudoaneurysm likely formed shortly after the initial AMI and remained stable over the long term, further supporting its chronic characteristics.

Traditional treatment options for LVP include conservative medical management and surgical repair. ¹⁰ In recent years, percutaneous interventional closure has gained attention as an emerging treatment approach, utilizing occluders to seal the neck of the aneurysm and effectively reduce the risk of rupture. ¹¹ In this case, the small size of the LVP (10 × 11 mm), its calcified characteristics (10 × 10 mm), the absence of rupture over 25 years, and the patient’s hemodynamic stability during hospitalization all suggest a high degree of structural stability. Given the patient’s refusal of surgical intervention, PCI combined with postoperative medical therapy was chosen, which likely played a key role in preserving cardiac function and maintaining the stability of the LVP. Although the patient is currently stable, the potential risks associated with LVP warrant close monitoring and long-term follow-up.

Conclusion

This case underscores the importance of regular cardiac evaluations in post-AMI patients and the need for timely, individualized treatment strategies when LVP is detected. While percutaneous interventional closure represents a promising new treatment option for LVP, the risks associated with conservative management must still be carefully evaluated, particularly for patients who decline surgery. It is essential to emphasize that the decision between conservative treatment and surgical intervention should be guided by the characteristics of the pseudoaneurysm, the patient’s clinical stability, and their preferences. Future research should focus on further elucidating the natural history of LVP, identifying optimal treatment strategies, and improving understanding of its long-term prognosis.

This study report complies with the CARE guidelines. ¹²