Left ventricular pseudoaneurysm with a left-to-right shunt is extremely rare, requiring surgery if symptomatic; however, surgery has a high risk. Here, the case of a 77-year-old man with heart failure symptoms is reported, in which he develops a giant left ventricular pseudoaneurysm 16 months after ventricular septal perforation repair as a result of acute myocardial infarction, with mild shunt blood flow from the pseudoaneurysm to the right ventricle. Intraoperative findings showed a free wall rupture along the area where the patch was secured during the initial surgery. The patient was discharged on postoperative day 13, and postoperative examination revealed no abnormalities.
Although surgery is the recommended approach for symptomatic LVPA, the disease course is relatively gradual; therefore, surgical risk should be considered in determining a treatment plan.
Although speculative, during VSP repair, it is suggested that special attention be given to needle penetration from the LV cavity into the LV wall, as it can potentially result in free wall rupture.
The presence of an L-R shunt should be carefully explored when treating LVPA.
Abbreviations and Acronyms
The extended sandwich patch technique is commonly performed for ventricular septal perforation (VSP) after acute myocardial infarction (AMI); however, little is known about the technique’s chronic complications. Here, a case of chronic left ventricular pseudoaneurysm (LVPA) complicated by a left-to-right (L-R) shunt and its causes are reported and discussed.
Presentation and Physical Examination
A 77-year-old man was transferred to the hospital after visiting his physician 1 week after experiencing sudden respiratory distress. Upon admission, the patient presented with mild shortness of breath and bilateral leg edema but stable vital signs.
Sixteen months earlier, the patient had presented to the hospital after having experienced persistent chest pain for 9 days. Emergency coronary angiography revealed 100% stenosis of the proximal right coronary artery, and echocardiography revealed VSP. Emergent VSP repair was performed using the posterior right ventricular (RV) approach. Intraoperative findings revealed a large VSP from the apex to the base of the heart (5 cm × 2 cm). A bovine pericardial patch was secured by transmurally bringing the needles (3-0 polypropylene) from the LV cavity to the LV wall beyond the right coronary artery posterior descending branch and from the LV cavity to the RV cavity through the ventricular septum. Transmural sutures were reinforced using pledgets, and sutures were introduced into the RV cavity and passed through a second patch. The RV incision line was closed using 2 felt strips. Coronary revascularization of the right coronary artery was not performed. Postoperative echocardiographic imaging revealed no residual shunts or other mechanical complications. The patient was discharged and followed up at a local clinic.
The differential diagnosis included recurrent VSP, new MI, and congestive heart failure secondary to low cardiac function.
Transthoracic echocardiographic imaging showed an ejection fraction of 28%, no recurrent VSP, and a giant LVPA. A mild L-R shunt from the aneurysm to the RV was also observed, with a pulmonary to systemic flow ratio of 1.4:1 (Fig. 1A and Fig. 1B). Enhanced computed tomography and cardiac magnetic resonance imaging scans confirmed a giant LVPA originating near the apex of the left ventricle (Fig. 2A and Fig. 2B). Drug therapy for heart failure symptoms associated with LVPA or L-R shunts was initiated. The patient was discharged from the hospital after his symptoms improved, but they reappeared after 2 months. It was therefore decided to perform surgery after fully explaining the associated high risk to the patient.
Surgery was performed via median sternotomy. Cardiopulmonary bypass was established between the right femoral artery and femoral vein before the sternotomy. An LV vent was inserted through the right upper pulmonary vein, and cardiac arrest was achieved using anterograde cardioplegia. Upon clamping the ascending aorta and opening the LVPA, a 70 mm × 30 mm defect was observed in the posterior LV wall (Fig. 3A). This defect was possibly a result of the tearing of the transmural suture from the LV cavity to the LV wall during the previous VSP repair. The trimmed defect was closed using 2-0 polypropylene mattress sutures with patches made of artificial vessels (J Graft; Japan Lifeline). An L-R shunt near the previous RV incision line was also closed with 4-0 polypropylene (Fig. 3B). The surgical schema is shown in Fig. 3C.
The patient was transferred to the intensive care unit and extubated on postoperative day 1. He was moved to the general ward on postoperative day 5 and discharged on postoperative day 13, with resolution of preoperative symptoms.
Postoperative cardiac magnetic resonance imaging performed 2 months after surgery showed successful LVPA repair without leakage through the patch and a completely thrombosed aneurysmal sac (Fig. 4).
Left ventricular pseudoaneurysm is a rare complication after AMI and is defined as a rupture of the free wall of the left ventricle composed of pericardial adhesions, epicardium, or both.1 Most frequently, the condition arises after AMI, but it can also be a complication of cardiac surgery, trauma, or infection.2 Postinfarction LVPA can be acute (<2 weeks after AMI), subacute, or chronic (>3 months after AMI), and the natural history of the chronic LVPA remains clear.2,3 In the present case, the onset of the disease was sudden, and free wall rupture may have occurred at that time. The patient ultimately underwent surgery 2 months after onset, during which time his vital signs remained stable. As this case suggests, LVPA often has a relatively stable course, and the timing of surgery is debatable. Prêtre et al3 reported that surgery is preferable in patients with symptomatic LVPA, especially when the LVPA is discovered in the first 3 months after AMI and when it expands or is large (>3 cm). In this case, initially, conservative treatment was planned because of the high risk of surgery; however, considering the persistent symptoms and the size of the aneurysm, the decision was made to proceed with surgery.
In the present case, the LVPA orifice was observed transmurally along the penetrating needle from the LV cavity to the free wall. The VSP was large and likely involved substantial extensive MI. The fragile post-AMI tissue may have contributed to the development of LVPA. The possibility of complications from VSP repair must also be considered because the area is thought to be dominated by the left coronary artery without stenosis. Although pledgets were used to reduce stress on the LV walls, the tear is still believed to have occurred in this area. Reevaluating the fundamental principles of needle penetration from the LV cavity to the LV wall, ensuring a perpendicular approach to the myocardium, and avoiding excessive tension in the ligation may therefore be necessary to prevent such situations. This case is also unique because of the presence of an L-R shunt from the LVPA to the RV. Bryniarski et al4 reported on a patient with LVPA with an L-R shunt 6 weeks after inferior MI. In the present case, the shunt hole was small and difficult to identify without preoperative echocardiographic imaging. In the future, when operating on patients with LVPA, surgeons must be mindful of the presence of a shunt.
Surgery is preferred for symptomatic LVPA, and patients should be carefully monitored for complications associated with L-R shunts. Further investigation of surgical management in patients with L-R shunts is warranted.
Open Access: © 2023 The Author(s). Published by The Texas Heart Institute®. This is an Open Access article under the terms of the Creative Commons Attribution-NonCommercial License (CC BY-NC, https://creativecommons.org/licenses/by-nc/4.0/), which permits use and distribution in any medium, provided the original work is properly cited, and the use is noncommercial.
Author Contributions: Yojiro Machii wrote the original draft of this manuscript. Makoto Taoka wrote, reviewed, and edited the manuscript. Yuki Hayashi supervised and contributed to the writing, review, and editing of the manuscript. Atsushi Harada, Keita Kamata, and Masashi Tanaka supervised the development of this manuscript.
Conflict of Interest Disclosure: None.