Left Ventricular Pseudoaneurysm Following Anterior Myocardial Infarction

Abstract

Left ventricular pseudoaneurysm (LVP) is a rare but severe mechanical complication of myocardial infarction (MI), associated with high risk of rupture and mortality. Accurate diagnosis relies on multimodality imaging, and timely surgical repair remains the mainstay of treatment. We report the case of a 78-year-old man, a former heavy smoker, who presented with progressive exertional dyspnea and bilateral lower limb edema. The electrocardiogram showed sequelae of a prior anterior MI with suspected aneurysmal evolution. Transthoracic echocardiography revealed a dilated left ventricle with severely impaired systolic function (left ventricular ejection fraction [LVEF] –20%) and a dyskinetic, aneurysmal apex. Coronary angiography showed two-vessel disease, while cardiac magnetic resonance confirmed a nonacute transmural infarction of the anterior and septal walls complicated by a large pseudoaneurysm with mural and extramural thrombus. Because of the high risk of progression and embolic complications, the patient underwent elective surgical repair with an endoventricular circular patch plasty (Dor procedure). The postoperative recovery was uneventful. At 2-weeks, echocardiography showed a favorable left ventricular (LV) remodeling, with an important reduction in end-diastolic volume (from 230 to 150 mL), and a marked improvement in systolic function (LVEF from 20% to 39%). This case highlights the critical role of imaging in diagnosing and characterizing LVP, as well as the therapeutic efficacy of surgical ventricular reconstruction. Early surgical intervention can prevent catastrophic rupture and restore LV geometry, improving global systolic performance. Multidisciplinary evaluation is essential to guide management, and less invasive percutaneous approaches may represent future alternatives in high-risk surgical candidates.

INTRODUCTION

Mechanical complications of acute myocardial infarction (MI), including ventricular septal rupture, papillary muscle rupture, and free wall rupture (FWR), are rare but life-threatening events that demand prompt recognition and urgent intervention.[1] The incidence of these complications, particularly after ST-elevation MI (STEMI), has markedly declined in the contemporary era of primary percutaneous coronary intervention. Nevertheless, mechanical complications still occur in 0.27%–0.91% of STEMI cases.[2] Among them, FWR is one of the most devastating, typically manifesting within the 1^st week after the infarction onset and featuring an extremely poor prognosis, with reported mortality approaching 50% even with surgical repair and up to 90% with conservative management.[3]

In some, more fortunate, cases, FWR may be contained by the adherent visceral pericardium or by an organized thrombus, resulting in the formation of a left ventricular pseudoaneurysm (LVP). Unlike true aneurysms, which still feature all layers of the ventricular wall, pseudoaneurysms completely lack myocardial tissue and are limited only by pericardial adhesions and/or thrombotic material.[4] Their natural history is still, however, unfavorable, with spontaneous rupture occurring in 30%–45% of cases.

Clinical manifestations of LVP are often nonspecific and may include chest pain, dyspnea, and fatigue. Importantly, some patients remain asymptomatic, therefore the role of imaging in diagnosis is critical. Transthoracic echocardiography (TTE) is usually the first-line modality, but advanced imaging techniques, including cardiac computed tomography and, especially, cardiac magnetic resonance (CMR) imaging, provide superior spatial resolution and tissue characterization, allowing for an accurate differentiation between true and false aneurysms.[4,5,6]

Surgical repair remains the cornerstone of treatment, typically achieved through direct suture or patch closure to reestablish ventricular integrity. In selected high-risk patients deemed unsuitable for surgery, conservative management with strict monitoring may be considered, although this approach carries a substantially higher risk of rupture and adverse outcomes.[7]

We describe the case of a 78-year-old man who developed a ventricular pseudoaneurysm following an acute anterior MI and successfully underwent surgical ventriculoplasty.

CASE REPORT

A 78-year-old man, a former heavy smoker (40 + pack-years, having quitted 1 month prior), presented with progressive exertional dyspnea (New York Heart Association - IIb–III) and bilateral lower limb edema. His medical history included chronic obstructive pulmonary disease and stage 1 chronic kidney disease. He denied hypertension, diabetes, dyslipidemia, and any family history of coronary heart disease. Notably, 2 weeks earlier, he reported a self-limited episode of oppressive chest pain, lasting about 2 h.

The electrocardiogram revealed signs of a prior anterior MI, with QS complexes in V2–V4 and Q waves in DI–aVL, together with features of possible aneurysmal evolution evidenced by persistent ST-segment elevation in V4–V6.

TTE revealed a dilated left ventricle with severely depressed systolic function (left ventricular ejection fraction [LVEF] 20%) and a dyskinetic, aneurysmal apex [Figure 1]. Moderate mitral regurgitation and elevated pulmonary artery pressures (estimated at 50 mmHg) were also present.

Figure 1.

Transthoracic echocardiography (apical three-chamber [a] and two-chamber [b]) showing a pseudoaneurysm suggested by a low neck-to-body ratio, with mural thrombus along the distal anterior wall and a dyskinetic aneurysmal apex

Cardiac biomarkers were abnormal (high-sensitivity troponin-T, 46 ng/L; N-terminus-pro brain-type natriuretic peptide, 6100 pg/mL).

Coronary angiography showed 2-vessel disease with occlusion of the first diagonal branch, 85% stenosis of the first marginal branch, and delayed flow (thrombolysis in MI 2) in the left anterior descending coronary artery [Figure 2].

Figure 2.

Invasive coronary angiography demonstrating two-vessel disease: (a) Left anterior oblique (LAO) caudal “spider” view showing the severe (85%) proximal stenosis of the first obtuse marginal branch, (b) LAO view showing diffuse right coronary atherosclerotic irregularities without flow-limiting stenoses, (c) Right anterior oblique caudal view, confirming critical proximal stenosis of the first marginal branch, (d) Anteroposterior cranial view showing total occlusion of the first diagonal branch

CMR imaging confirmed the presence of an extensive transmural antero-septal infarction, complicated by a large pseudoaneurysm with mural and extramural thrombus [Figure 3]. Because of the patient’s poor breath-hold capacity, images were acquired with a single-shot turbo sequence aided by parallel imaging, resulting in suboptimal, but still diagnostic image quality.

Figure 3.

Late gadolinium enhancement cardiac magnetic resonance using phase sensitive inversion recovery T1 weighted fast gradient echo sequences, (a) Three chamber view, obtained with a shorter inversion time, reveals both intramural and extramural thrombus, identified by the “edged”; (b) Short axis view shows demonstrating ventricular wall discontinuity with distorted contour and intramyocardial thrombus, bounded by a thin hyperintense rim consistent with thickened pericardium

Because of the high risk of rupture and embolic complications, the patient was referred to surgical treatment.

An elective left ventriculoplasty was performed via median sternotomy and cardiopulmonary bypass. The procedure consisted of an endoventricular circular patch plasty (Dor procedure),[8] with resection of the pseudoaneurysm and reconstruction of the ventricular cavity using a synthetic patch [Figure 4]. Although the left internal mammary artery was harvested, no bypass grafting was performed due to the absence of suitable distal targets. At the end of the operation, transesophageal echocardiography confirmed a successful ventricular reconstruction, with restoration of the left ventricular (LV) geometry, preserved mitral subvalvular mechanics, and no evidence of pericardial effusion, mitral regurgitation, or systolic anterior motion of the anterior leaflet [Figure 5].

Figure 4.

Intraoperative sequence of endoventricular circular patch plasty (Dor procedure): pseudoaneurysm resection with thrombus evacuation, Dacron patch modeling and implantation for ventricular cavity reconstruction, and final purse-string closure

Figure 5.

Transesophageal echocardiography (mid-esophageal four-chamber view) obtained before (a) and after (b) surgical repair: (a) apical septal intracavitary thrombus; (b) well-seated hyperechogenic Dacron patch contiguous with native myocardium, restoring left ventricular geometry

The postoperative course was uneventful. The patient was extubated on the day of surgery, required only short-term vasopressor support, and was hemodynamically stable by postoperative day 4. He was transferred back to the cardiology ward on postoperative day 5.

Two weeks after surgery, follow-up echocardiography showed restoration of a more physiological LV geometry and significant improvement in systolic performance. The end-diastolic volume decreased from 224 mL (indexed 132 mL/m²) to 150 mL (indexed 89 mL/m²), while LVEF improved from 20% to approximately 39% [Figure 6]. Mitral regurgitation was reduced from moderate to mild degree, and right ventricular function remained preserved. These findings confirmed the favorable impact of surgical remodeling on global cardiac function in this case of ischemic cardiomyopathy complicated by LVP.

Figure 6.

Follow-up transthoracic echocardiography (apical three-chamber [a] and two-chamber [b]) showing improved, more physiological left ventricular geometry with marked reduction in end-diastolic volume after surgery

DISCUSSION

The case here presented illustrates the management of a sub-acute anterior apical LVP following a previously unrecognized MI, successfully treated with elective endoventricular circular patch plasty (Dor procedure). The patient presented with progressive dyspnea, and multimodality imaging confirmed a severely impaired systolic function (LVEF 20%) and apical pseudoaneurysm with mural and extramural thrombus, justifying surgical repair due to the high risk of progression to overt rupture.

Acute and subacute LVPs generally require urgent surgical intervention due to their high risk of rupture, whereas chronic pseudoaneurysms, particularly those detected incidentally, pose greater therapeutic challenges.[3,9] In asymptomatic cases, conservative management may be considered. Moreno et al. reported a 4-year survival of 74.1% with medical therapy,[10] although more recent evidence favors surgical repair even for small pseudoaneurysms.[7] Current recommendations suggest intervention when the pseudoaneurysm exceeds 3 cm, shows progressive enlargement, or is associated with symptoms such as heart failure, systemic embolism, or mural thrombus.[4]

Surgical repair remains the standard of care for suitable candidates and may be performed through external or internal approaches, selected according to the aneurysm location, neck characteristics, and the need for concomitant procedures. External repair enables complete resection and minimizes manipulation near the mitral apparatus,[11] whereas internal approaches (transventricular or transatrial) offer superior exposure for precise reconstruction, especially in the setting of subvalvular involvement or associated valve disease.[12,13] For anterior–apical pseudoaneurysms, the Dor procedure is particularly advantageous, as it combines purse-string sutures to reduce the aneurysmal neck with a Dacron patch to exclude the pseudoaneurysm, thereby restoring the conical geometry of the left ventricle while preserving cavity volume.[8]

Several alternative surgical techniques have been described. Elgharably et al. proposed the triple-layer “Empanada patch,” in which bovine pericardium is folded over a Dacron base to enhance rigidity and prevent systolic bulging.[14] Posterior or basal pseudoaneurysms are usually managed with simpler patch repairs to avoid distortion of the mitral valve apparatus.[15] Regardless of the technique, the use of Teflon felt strips between sutures and the myocardium is critical for reinforcing fragile tissue and ensuring hemostasis.

Despite technical advances, surgical mortality remains considerable (13%–28%), largely influenced by preexisting LV dysfunction and concomitant valvular disease rather than operative complexity.[4] In our patient, early postoperative recovery was favorable, with a marked improvement in LV function (LVEF rising from 20% to 39% at 2 weeks), underscoring the potential for functional benefit with ventricular restoration procedures.

Percutaneous strategies are emerging as alternatives for patients at prohibitively high surgical risk. Devices such as septal occluders and coils have been deployed in selected cases with encouraging but heterogeneous results.[16,17] Procedural success is highly dependent on anatomical suitability, particularly depending on the presence of a well-defined neck and an adequate landing zone. Nevertheless, concerns remain regarding device embolization and uncertain long-term durability, emphasizing the need for cautious patient selection and multidisciplinary discussion.[4]

CONCLUSION

LVP is a rare but life-threatening complication of MI that requires timely recognition and careful therapeutic planning. Multimodality imaging, especially CMR imaging, plays a critical role in establishing the diagnosis, differentiating pseudoaneurysm from true aneurysm, and guiding surgical decision-making.

In this case, the combination of progressive heart failure symptoms, severely depressed systolic function, and the presence of a mural thrombus provided a clear indication for surgery. Elective endoventricular patch plasty (Dor procedure) resulted in successful exclusion of the pseudoaneurysm, restoration of ventricular geometry, and significant improvement in global LV performance.

Although surgical repair remains the gold standard for most patients, management decisions should be individualized, weighing operative risk, clinical presentation, and anatomical features. Emerging percutaneous approaches may provide alternatives in selected high-risk surgical candidates, though long-term outcomes remain uncertain.

Declaration of patient consent

The authors certify that they have obtained all appropriate patient consent forms. In the form, the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.

Conflicts of interest

There are no conflicts of interest.

Funding Statement

Nil.