Defusing a ticking time bomb – percutaneous intervention for a giant coronary pseudoaneurysm

Defusing a ticking time bomb – percutaneous intervention for a giant coronary pseudoaneurysm | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Case Report Defusing a ticking time bomb – percutaneous intervention for a giant coronary pseudoaneurysm Alimi Ahmad Hatib, An Shing Ang, Randal Jun Bang Low This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8999186/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted 13 You are reading this latest preprint version Abstract Background Giant coronary pseudoaneurysms (PSAs) are extremely rare and typically managed surgically. Our case demonstrates an alternative approach with percutaneous intervention using covered stents. Case Summary A 62-year-old male underwent percutaneous coronary intervention (PCI) to the left main (LM) and left anterior descending (LAD) arteries for non-ST elevation myocardial infarction (NSTEMI) complicated by cardiogenic shock in the setting of concurrent Methicillin-Sensitive Staphylococcus Aureus (MSSA) bacteraemia. During staged PCI to the right coronary artery (RCA), a relook angiogram revealed a giant LM-LAD PSA with coronary steal phenomenon. The PSA was confirmed on multi-modality cardiac imaging and treatment with covered stents was performed successfully. Discussion This showcases the importance of multi-modality imaging and a multidisciplinary approach in managing an unusual presentation of coronary PSA. The use of covered stents for treatment is feasible and allowed successful treatment of the giant PSA, avoiding potentially catastrophic complications. Take home messages Coronary PSAs are rare and associated with fatal complications. PCI with covered stents is a viable treatment option. Coronary pseudoaneurysm percutaneous coronary intervention Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 Background Coronary artery pseudoaneurysm (PSA) post percutaneous coronary intervention (PCI) is a rare and potentially life-threatening complication, with real-world incidence remaining unclear due to paucity of data. The development of PSAs is postulated to be due to vessel wall damage that occurs during PCI. Other aetiologies include inflammatory disease, infection and external trauma. Furthermore, there are only a handful of documented cases of patients presenting with giant coronary PSAs (defined as being > 50 mm in diameter). We report a rare and unusual case of a giant left main (LM) to left anterior descending (LAD) coronary PSA that we successfully treated percutaneously in a middle-aged male. Initial presentation A 62-year-old male with diabetes mellitus, hypertension, hyperlipidaemia and end-stage kidney disease (ESKD) presented initially for new-onset fast atrial fibrillation (AF). He subsequently mounted a 38.6-degree fever with blood cultures growing Methicillin Susceptible Staphylococcus Aureus (MSSA) . Culture-directed intravenous antibiotics was initiated with subsequent resolution of his febrile illness with stable hemodynamics. 3 days later, he developed sudden onset chest pain with troponin elevation from 223 ng/L to > 22000 ng/L (reference range: 0-18 ng/L). Furthermore, he became hypotensive requiring intravenous vasopressor support. The diagnosis of NSTEMI with predominantly cardiogenic shock was made, warranting emergent coronary angiography. The diagnostic angiogram showed critical LM-LAD disease and heavily calcified RCA stenoses. As the patient had already received a few days of culture directed antibiotics with resolution of fever and improvement of inflammatory markers, the decision was made by the operator to proceed with PCI to the LM-LAD given the presentation of NSTEMI and cardiogenic shock. PCI to the LM-LAD was subsequently performed uneventfully (image 1) . The transthoracic echocardiogram (TTE) revealed an ejection fraction (EF) of 35% with multivessel territory wall motion abnormalities. He was stable on discharge and completed the course of culture-directed antibiotics. Repeat cardiac imaging and HEART team discussion He remained asymptomatic post-hospitalisation and was tolerating regular dialysis sessions. He presented again 8 weeks later for an elective staged PCI to the right coronary artery (RCA). A relook angiogram of the LM-LAD stents revealed an unexpected finding. The relook angiogram of the left coronary system revealed no flow in the LM-LAD stents with rapid contrast filling of a large circular cavity adjacent to the proximal LM-ostial LAD (image 2) . Different projections revealed that the cavity was not intracardiac, thus raising the possibility of a giant coronary PSA. The patient was taken off table for evaluation with multimodality imaging. TTE confirms a large pseudoaneurysm adjacent to the left coronary cusp, with the presence of spontaneous echo contrast and a clear connection between the origin of the LM and the cavity on colour doppler interrogation . Computed tomography coronary angiography (CTCA) showed the large pseudoaneurysm measuring 8.3 x 7.4 cm, for which the origin was deemed to be at the junction of the LM and LAD. There was no intraluminal contrast in the LAD stents beyond the LM (image 3), indicating significant steal phenomenon with blood shunted directly from the LM into the pseudoaneurysm cavity Chest X-Ray also revealed an ovoid structure adjacent to the left heart border on anterior-posterior projection (image 4). A HEART team discussion was held between interventional cardiologists and cardiothoracic surgeons to determine the best option for management. The team agreed that this giant coronary PSA could not be left untreated due to the high risk of spontaneous rupture given its very large size. The surgical team assessed the patient as high-surgical risk owing to the complexity of the procedure, low LVEF and underlying ESKD. Thus, percutaneous closure was deemed the only feasible approach. The team also concluded that PCI to the RCA should be performed first given the residual severe disease. Details of management First, PCI to the RCA was performed with implantation of 2 drug eluting stents after calcium modification with rotational atherectomy (Boston scientific, Massachusetts, USA) and intravascular lithotripsy (image 5) . Minimal contrast and radiation were utilised given the expected challenges and time required for PCI to the LAD PSA. This was made possible with intravascular ultrasound (IVUS) guidance. Next, LM-LAD stent patency was initially confirmed through routine wiring. Thereafter, a guide extension catheter (GEC) was introduced, and preserved mid to distal LAD flow was confirmed on contrast injection through the GEC. IVUS imaging was then performed, which unexpectedly revealed multiple areas of “floating stents” with no adjacent vessel wall along a long segment of the proximal to mid LAD (image 6) . This raised the possibility of multiple points of communication from the LM-LAD into the same PSA cavity, contrary to what was initially suggested on TTE and CTCA. Multiple images were obtained while gradually pulling back the GEC, which confirmed this suspicion (image 7) . A total of 6 overlapping PK Papyrus covered stents (Biotronik, Berlin, Germany) were placed from the ostial LM to mid LAD, which finally led to the successful sealing of all leaks and restoration of TIMI 3 flow in the LAD (image 8) . Given an existing communication between the LM artery and the pseudoaneurysm, placement of the covered stent necessitated jailing the left circumflex (LCx) artery. An attempt to fenestrate the covered stent into the LCx was technically challenging and ultimately unsuccessful. Fortunately, the patient had a very dominant RCA and the loss of LCx flow was well tolerated, with no symptomatic or hemodynamic consequences. Outcome and follow up The following day, a repeat TTE confirmed the presence of a thrombus forming within the PSA cavity. The previous connection seen on colour doppler between the LM and PSA was no longer present (image 9). He was discharged well and stable shortly after. A repeat TTE done 4 months later showed complete resolution of the pseudoaneurysm cavity (image 9). Unfortunately, he declined a repeat CT coronary angiogram. He was reviewed in subsequent clinic visits and was tolerating regular dialysis sessions without issues. After 1 year of being on dual anti platelet therapy (DAPT), his haemoglobin level was stable, and he had no bleeding manifestations. Given that he had multiple covered stents placed with risks of in-stent restenosis and thrombosis, he was continued on long term DAPT in addition to aggressive LDL lowering therapies with a target LDL of less than 1.4 mmol/L. Discussion In this case, there was a clear indication to definitively treat the patient’s giant PSA given its rapid progression in size and presence of coronary steal phenomenon. Left untreated, the potential sequelae included spontaneous rupture with tamponade and LAD territory ischemia or infarction with subsequent malignant arrhythmias. Given its rarity and complexity, a HEART team discussion was imperative to explore management options before embarking on the procedure. Furthermore, acquiring comprehensive information on the size and location of the PSA through multi-modality imaging also proved essential in pre-procedural planning. The successful use of covered stents for percutaneous closure of coronary PSAs has been documented in case reports. Other proposed management options include the deployment of coils. In our case, however, given the size and extent of the PSA, along with multiple communication sites, achieving a complete seal with coils would be technically unfeasible. Furthermore, the risk of coil embolization into the LM or LAD will lead to more detrimental consequences. Hence, the team decided on percutaneous intervention with covered stent placement. The strategy for PCI to the giant LM PSA was adapted from bailout techniques in PCI of LM coronary perforations. The drawback of LM covered stenting is the potential for jailing of side branches; in this case the circumflex artery (LCx). Furthermore, we acknowledge the long-term thrombotic and in-stent restenosis risks of deploying multiple covered stents. To mitigate this, the patient was placed on aggressive LDL lowering therapies and long term DAPT as tolerated. Despite meticulous pre-procedural planning, we were still faced with the unexpected challenge of plugging multiple leaks along the entire length of the LM to mid-LAD. Initially, it was believed that there was one “neck” originating from the LM-LAD junction, as confirmed on both TTE and CTCA. However, it was later understood in retrospect that, due to the lack of contrast flow into the proximal-mid LAD resulting from the coronary steal phenomenon, the more distal leaks beyond the level of LM could not be detected on CTCA. This could only be postulated based on IVUS findings and confirmed via GEC-assisted contrast injections. Nonetheless, we remained steadfast in the strategy of covered stenting and sealed all leaks. The presence of an organising thrombus within the PSA cavity, with a lack of colour Doppler flow 1-day post-procedure, was reassuring that the procedure was successful. Causes of coronary PSAs include trauma to the vessel wall during PCI, inflammation, infection and external trauma. While our patient had active MSSA bacteraemia, the acute onset of NSTEMI with cardiogenic shock necessitated urgent intervention rather than deferring until the bacteraemia was adequately treated. Considering S. Aureus is the most common pathogen in documented cases of coronary stent infections, and the anatomically extensive involvement (suggesting the pseudoaneurysm may indeed be a healed abscess), it supports our postulation that the presence of multiple leaks along the LM-LAD could have been due to an infected coronary stent, resulting in weakening of the adjacent vessel wall. Alternatively, substantial mechanical trauma, in the form of deep coronary dissections during the index PCI, may have contributed to the formation of the PSA. Conclusion While coronary PSAs are already an uncommon complication post-PCI, giant PSAs are exceedingly rare. The available evidence reveals that surgery was the primary treatment modality. We present a case of an 8.3 x 7.4 cm coronary PSA that was successfully treated percutaneously with covered stents. This case adds another layer of complexity in that the operators were not only dealing with a giant PSA but one with multiple leaks/necks to be addressed. However, owing to meticulous pre-procedural strategizing with the HEART team and information from multi-modality imaging, the operators successfully defused the ticking time bomb. This case illustrates that PCI can be a viable and less invasive alterative to surgery for the treatment of giant PSAs. Declarations Ethics approval and consent to participate – Not applicable Consent for publication – informed consent has been obtained by the patient for his clinical details to be published in this case report Availability of data and materials – Not applicable Competing interests – The authors declare that they have no competing interests Funding – Not applicable Authors ‘contributions – AAH was the primary operator for the case and wrote the report. RL was the supervisor and co-operator for the case and vetted the report. AAS contributed by performing the literature review to supplement the case. Acknowledgements – Not applicable References Svante Gersch, Hassina Baraki, Karl Toischer, Progression and interventional therapy of a coronary pseudoaneurysm: a case report, European Heart Journal - Case Reports , Volume 7, Issue 1, January 2023, ytac478, https://doi.org/10.1093/ehjcr/ytac478 Sharma R, Ruia AV. A case report of pseudoaneurysm of coronary artery within a month of percutaneous coronary intervention. Eur Heart J Case Rep . 2022;6(5):ytac175. Published 2022 Apr 21. doi:10.1093/ehjcr/ytac175 Takagi, Kensuke et al (2023). Bail-Out Techniques in Percutaneous Intervention for Ellis Grade III Coronary Perforation in Left Main Distal Bifurcation Lesions, JSCAI, Volume 2, Issue 3, 100609 Elieson M, Mixon T, Carpenter J. Coronary stent infections: a case report and literature review. Tex Heart Inst J . 2012;39(6):884-889. Additional Declarations No competing interests reported. Supplementary Files Video1PSAPrePCIcompressed.mp4 Video2PSAPrePCIEcho.mp4 Video3PSAmultipleleakscompressed.mp4 Video4PSApostPCIcompressed.mp4 Video5PSAPostPCID1echo.mp4 Video6PSApostPCIecho4months.mp4 Cite Share Download PDF Status: Under Review Version 1 posted Editorial decision: Revision requested 06 Apr, 2026 Reviews received at journal 04 Apr, 2026 Reviews received at journal 26 Mar, 2026 Reviewers agreed at journal 26 Mar, 2026 Reviewers agreed at journal 20 Mar, 2026 Reviewers agreed at journal 20 Mar, 2026 Reviews received at journal 19 Mar, 2026 Reviewers agreed at journal 19 Mar, 2026 Reviewers invited by journal 18 Mar, 2026 Editor assigned by journal 18 Mar, 2026 Editor invited by journal 10 Mar, 2026 Submission checks completed at journal 09 Mar, 2026 First submitted to journal 05 Mar, 2026 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-8999186","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Case Report","associatedPublications":[],"authors":[{"id":609841828,"identity":"2811197c-0190-464a-87fd-70f9bebacfef","order_by":0,"name":"Alimi Ahmad Hatib","email":"data:image/png;base64,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","orcid":"","institution":"Woodlands Hospital","correspondingAuthor":true,"prefix":"","firstName":"Alimi","middleName":"Ahmad","lastName":"Hatib","suffix":""},{"id":609841830,"identity":"90d5040f-bcac-460f-aea5-a31784a77df4","order_by":1,"name":"An Shing Ang","email":"","orcid":"","institution":"Woodlands Hospital","correspondingAuthor":false,"prefix":"","firstName":"An","middleName":"Shing","lastName":"Ang","suffix":""},{"id":609841831,"identity":"1c942509-0153-4e4a-b77b-135adf2e7e93","order_by":2,"name":"Randal Jun Bang Low","email":"","orcid":"","institution":"Woodlands Hospital","correspondingAuthor":false,"prefix":"","firstName":"Randal","middleName":"Jun Bang","lastName":"Low","suffix":""}],"badges":[],"createdAt":"2026-03-01 04:38:12","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-8999186/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-8999186/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":105195936,"identity":"c6614cdd-5517-4ec6-97ea-e0e4c7c3d64d","added_by":"auto","created_at":"2026-03-23 10:17:53","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":682876,"visible":true,"origin":"","legend":"\u003cp\u003e(A) Caudal and Cranial views showing critical LM-LAD stenoses (★)\u003c/p\u003e\n\u003cp\u003e(B) Caudal and Cranial views post PCI with drug-eluting stents to LM-LAD (red arrows)\u003c/p\u003e\n\u003cp\u003e(C) Angiogram of the RCA\u003c/p\u003e","description":"","filename":"1.png","url":"https://assets-eu.researchsquare.com/files/rs-8999186/v1/4b7038186c577dda85f7e872.png"},{"id":105195937,"identity":"69cd07dd-f3c9-4e11-83e7-34e9c3db4dd4","added_by":"auto","created_at":"2026-03-23 10:17:53","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":621863,"visible":true,"origin":"","legend":"\u003cp\u003eRelook angiogram images of the left coronary system 8 weeks post index PCI showing contrast extravasation into a large circular cavity (white outlines) adjacent to the LM with no flow into the LAD (★ indicating previous LM-LAD stents)\u003c/p\u003e","description":"","filename":"2.png","url":"https://assets-eu.researchsquare.com/files/rs-8999186/v1/dc1954ce0172d7a85ee291f1.png"},{"id":105564045,"identity":"a811270f-84c7-44f7-a0a6-6205b75d9a3f","added_by":"auto","created_at":"2026-03-27 12:48:35","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":168190,"visible":true,"origin":"","legend":"\u003cp\u003eCTCA showing large 8.3 x 7.4 cm pseudoaneurysm (red outline) originating from LM-LAD junction. LM to proximal LAD stent seen (★) with no contrast flow in the LAD\u003c/p\u003e","description":"","filename":"3.png","url":"https://assets-eu.researchsquare.com/files/rs-8999186/v1/8c93862f2e50f18285ce9e81.png"},{"id":105195940,"identity":"017db79b-83c1-4c83-98e2-cd5f5c88abcc","added_by":"auto","created_at":"2026-03-23 10:17:53","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":771831,"visible":true,"origin":"","legend":"\u003cp\u003eChest X-rays on initial admission (A) and on discovery of giant PSA (B – red dotted lines)\u003c/p\u003e","description":"","filename":"4.png","url":"https://assets-eu.researchsquare.com/files/rs-8999186/v1/be2dd26f6f282fa154c1d8a7.png"},{"id":105195938,"identity":"3a559775-810b-47f0-9baa-e0d9da9c23a3","added_by":"auto","created_at":"2026-03-23 10:17:53","extension":"png","order_by":5,"title":"Figure 5","display":"","copyAsset":false,"role":"figure","size":633782,"visible":true,"origin":"","legend":"\u003cp\u003eRCA pre (A) and post (B) PCI\u003c/p\u003e","description":"","filename":"5.png","url":"https://assets-eu.researchsquare.com/files/rs-8999186/v1/d1c23782b252a9a4e32cec72.png"},{"id":105195941,"identity":"52723dd1-b7aa-4b1d-8655-a559ac7686af","added_by":"auto","created_at":"2026-03-23 10:17:53","extension":"png","order_by":6,"title":"Figure 6","display":"","copyAsset":false,"role":"figure","size":843344,"visible":true,"origin":"","legend":"\u003cp\u003eIVUS images of the proximal to mid LAD stents. (A) Well apposed stent (★) with vessel wall visualized (white dotted lines). (B) Portion of stent at 6-8 o’clock that is not in contact with any adjacent structure suggestive of a defect in the vessel wall. (C) Significant portion of stent “floating” without adjacent vessel well. Total length of “floating stents” is 31.40 mm\u003c/p\u003e","description":"","filename":"6.png","url":"https://assets-eu.researchsquare.com/files/rs-8999186/v1/6be20c70061664188869091d.png"},{"id":105195942,"identity":"59e52dbf-2ef3-4a3c-8f3a-b0a99607d7c1","added_by":"auto","created_at":"2026-03-23 10:17:53","extension":"png","order_by":7,"title":"Figure 7","display":"","copyAsset":false,"role":"figure","size":782760,"visible":true,"origin":"","legend":"\u003cp\u003eMultiple contrast injections while gradually pulling back the GEC (red arrow). (A) shows patent stents with at least 2 areas of contrast leaking into the PSA cavity (white arrows) in the proximal to mid LAD. (B) shows contrast leaking into the cavity (white outline and arrow) from the LM-LAD junction with no flow into the LAD – corresponding to CTCA findings\u003c/p\u003e","description":"","filename":"7.png","url":"https://assets-eu.researchsquare.com/files/rs-8999186/v1/c453a805d256bcfa4ea7eb68.png"},{"id":105195943,"identity":"1a06a552-f6fe-4ef6-9ffd-a58a08fd8043","added_by":"auto","created_at":"2026-03-23 10:17:53","extension":"png","order_by":8,"title":"Figure 8","display":"","copyAsset":false,"role":"figure","size":787851,"visible":true,"origin":"","legend":"\u003cp\u003eSuccessful sealing of all leaks into the giant PSA cavity (★) with restoration of TIMI 3 flow down the LAD after insertion of 6 overlapping covered stents (red arrows)\u003c/p\u003e","description":"","filename":"8.png","url":"https://assets-eu.researchsquare.com/files/rs-8999186/v1/e839524ef597e6157386737e.png"},{"id":105195944,"identity":"dd7064ab-f6b2-4aea-bd45-fb7c8690db90","added_by":"auto","created_at":"2026-03-23 10:17:53","extension":"png","order_by":9,"title":"Figure 9","display":"","copyAsset":false,"role":"figure","size":555853,"visible":true,"origin":"","legend":"\u003cp\u003eEcho images of giant PSA pre (A) and post (B, C) PCI. (A) Colour doppler flow seen entering the large PSA cavity with spontaneous echo contrast (white arrow and star). (B) Repeat TTE 1 day post PCI showing formation of large thrombus (★) within the PSA cavity with no colour doppler signals entering the cavity indicating successful sealing of leaks (C) Repeat TTE 4 months post PCI showing complete resolution of the pseudoaneurysm cavity\u003c/p\u003e","description":"","filename":"9.png","url":"https://assets-eu.researchsquare.com/files/rs-8999186/v1/4f9a8ee6bae27123df7d17b9.png"},{"id":106092948,"identity":"2c3fce33-7a2c-4a70-987e-34ed0e1a6ba0","added_by":"auto","created_at":"2026-04-03 11:31:21","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":7017937,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-8999186/v1/c8d12cc8-c115-4a30-a906-adffd49d4688.pdf"},{"id":105195948,"identity":"c89cf15d-2ce8-4bde-b122-de78dff86057","added_by":"auto","created_at":"2026-03-23 10:17:54","extension":"mp4","order_by":0,"title":"","display":"","copyAsset":false,"role":"supplement","size":18277617,"visible":true,"origin":"","legend":"","description":"","filename":"Video1PSAPrePCIcompressed.mp4","url":"https://assets-eu.researchsquare.com/files/rs-8999186/v1/d5cbce437efdaa1fc2e338a5.mp4"},{"id":105195950,"identity":"1a9a239b-7d19-4048-9d95-be76c21075b7","added_by":"auto","created_at":"2026-03-23 10:17:54","extension":"mp4","order_by":1,"title":"","display":"","copyAsset":false,"role":"supplement","size":18983104,"visible":true,"origin":"","legend":"","description":"","filename":"Video2PSAPrePCIEcho.mp4","url":"https://assets-eu.researchsquare.com/files/rs-8999186/v1/74b5cbce4af776f772504dd6.mp4"},{"id":105195947,"identity":"87c90054-af18-4496-89cc-d13ce0c4ace0","added_by":"auto","created_at":"2026-03-23 10:17:53","extension":"mp4","order_by":2,"title":"","display":"","copyAsset":false,"role":"supplement","size":13936852,"visible":true,"origin":"","legend":"","description":"","filename":"Video3PSAmultipleleakscompressed.mp4","url":"https://assets-eu.researchsquare.com/files/rs-8999186/v1/f1f0f1a28422a4b19c8ba32f.mp4"},{"id":105195949,"identity":"a0db6891-17b3-4001-81b7-84f4dbd5aa39","added_by":"auto","created_at":"2026-03-23 10:17:54","extension":"mp4","order_by":3,"title":"","display":"","copyAsset":false,"role":"supplement","size":15257350,"visible":true,"origin":"","legend":"","description":"","filename":"Video4PSApostPCIcompressed.mp4","url":"https://assets-eu.researchsquare.com/files/rs-8999186/v1/34b224e34eef1d92b241407a.mp4"},{"id":105195945,"identity":"80aebd3c-9260-47f0-95da-decb65f2a619","added_by":"auto","created_at":"2026-03-23 10:17:53","extension":"mp4","order_by":4,"title":"","display":"","copyAsset":false,"role":"supplement","size":8208273,"visible":true,"origin":"","legend":"","description":"","filename":"Video5PSAPostPCID1echo.mp4","url":"https://assets-eu.researchsquare.com/files/rs-8999186/v1/33061708914ad36d6a015686.mp4"},{"id":105195946,"identity":"35c36f11-3313-490f-8c27-a8b028fe6f59","added_by":"auto","created_at":"2026-03-23 10:17:53","extension":"mp4","order_by":5,"title":"","display":"","copyAsset":false,"role":"supplement","size":6307462,"visible":true,"origin":"","legend":"","description":"","filename":"Video6PSApostPCIecho4months.mp4","url":"https://assets-eu.researchsquare.com/files/rs-8999186/v1/f0a164bbad599587e1be4e15.mp4"}],"financialInterests":"No competing interests reported.","formattedTitle":"Defusing a ticking time bomb – percutaneous intervention for a giant coronary pseudoaneurysm","fulltext":[{"header":"Background","content":"\u003cp\u003eCoronary artery pseudoaneurysm (PSA) post percutaneous coronary intervention (PCI) is a rare and potentially life-threatening complication, with real-world incidence remaining unclear due to paucity of data. The development of PSAs is postulated to be due to vessel wall damage that occurs during PCI. Other aetiologies include inflammatory disease, infection and external trauma. Furthermore, there are only a handful of documented cases of patients presenting with giant coronary PSAs (defined as being \u0026gt;\u0026thinsp;50 mm in diameter). We report a rare and unusual case of a giant left main (LM) to left anterior descending (LAD) coronary PSA that we successfully treated percutaneously in a middle-aged male.\u003c/p\u003e"},{"header":"Initial presentation","content":"\u003cp\u003eA 62-year-old male with diabetes mellitus, hypertension, hyperlipidaemia and end-stage kidney disease (ESKD) presented initially for new-onset fast atrial fibrillation (AF). He subsequently mounted a 38.6-degree fever with blood cultures growing Methicillin Susceptible \u003cem\u003eStaphylococcus Aureus (MSSA)\u003c/em\u003e. Culture-directed intravenous antibiotics was initiated with subsequent resolution of his febrile illness with stable hemodynamics. 3 days later, he developed sudden onset chest pain with troponin elevation from 223 ng/L to \u0026gt; 22000 ng/L (reference range: 0-18 ng/L). Furthermore, he became hypotensive requiring intravenous vasopressor support. The diagnosis of NSTEMI with predominantly cardiogenic shock was made, warranting emergent coronary angiography. The diagnostic angiogram showed critical LM-LAD disease and heavily calcified RCA stenoses.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eAs the patient had already received a few days of culture directed antibiotics with resolution of fever and improvement of inflammatory markers, the decision was made by the operator to proceed with PCI to the LM-LAD given the presentation of NSTEMI and cardiogenic shock.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003ePCI to the LM-LAD was subsequently performed uneventfully \u003cstrong\u003e(image 1)\u003c/strong\u003e. The transthoracic echocardiogram (TTE) revealed an ejection fraction (EF) of 35% with multivessel territory wall motion abnormalities. He was stable on discharge and completed the course of culture-directed antibiotics.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eRepeat cardiac imaging and HEART team discussion\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eHe remained asymptomatic post-hospitalisation and was tolerating regular dialysis sessions. He presented again 8 weeks later for an elective staged PCI to the right coronary artery (RCA). A relook angiogram of the LM-LAD stents revealed an unexpected finding.\u003c/p\u003e\n\u003cp\u003eThe relook angiogram of the left coronary system revealed no flow in the LM-LAD stents with rapid contrast filling of a large circular cavity adjacent to the proximal LM-ostial LAD \u003cstrong\u003e(image 2)\u003c/strong\u003e. Different projections revealed that the cavity was not intracardiac, thus raising the possibility of a giant coronary PSA. The patient was taken off table for evaluation with multimodality imaging.\u003c/p\u003e\n\u003cp\u003eTTE confirms a large pseudoaneurysm adjacent to the left coronary cusp, with the presence of spontaneous echo contrast and a clear connection between the origin of the LM and the cavity on colour doppler interrogation\u003cstrong\u003e.\u003c/strong\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eComputed tomography coronary angiography (CTCA) showed the large pseudoaneurysm measuring 8.3 x 7.4 cm, for which the origin was deemed to be at the junction of the LM and LAD. There was no intraluminal contrast in the LAD stents beyond the LM \u003cstrong\u003e(image 3),\u0026nbsp;\u003c/strong\u003eindicating significant steal phenomenon with blood shunted directly from the LM into the pseudoaneurysm cavity\u003c/p\u003e\n\u003cp\u003eChest X-Ray also revealed an ovoid structure adjacent to the left heart border on anterior-posterior projection \u003cstrong\u003e(image 4).\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eA HEART team discussion was held between interventional cardiologists and cardiothoracic surgeons to determine the best option for management. The team agreed that this giant coronary PSA could not be left untreated due to the high risk of spontaneous rupture given its very large size. The surgical team assessed the patient as high-surgical risk owing to the complexity of the procedure, low LVEF and underlying ESKD. Thus, percutaneous closure was deemed the only feasible approach. The team also concluded that PCI to the RCA should be performed first given the residual severe disease.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eDetails of management\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eFirst, PCI to the RCA was performed with implantation of 2 drug eluting stents after calcium modification with rotational atherectomy (Boston scientific, Massachusetts, USA) and intravascular lithotripsy \u003cstrong\u003e(image 5)\u003c/strong\u003e. Minimal contrast and radiation were utilised given the expected challenges and time required for PCI to the LAD PSA. This was made possible with intravascular ultrasound (IVUS) guidance.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eNext, LM-LAD stent patency was initially confirmed through routine wiring. Thereafter, a guide extension catheter (GEC) was introduced, and preserved mid to distal LAD flow was confirmed on contrast injection through the GEC. IVUS imaging was then performed, which unexpectedly revealed multiple areas of \u0026ldquo;floating stents\u0026rdquo; with no adjacent vessel wall along a long segment of the proximal to mid LAD \u003cstrong\u003e(image 6)\u003c/strong\u003e. This raised the possibility of multiple points of communication from the LM-LAD into the same PSA cavity, contrary to what was initially suggested on TTE and CTCA. Multiple images were obtained while gradually pulling back the GEC, which confirmed this suspicion \u003cstrong\u003e(image 7)\u003c/strong\u003e.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eA total of 6 overlapping \u003cem\u003ePK Papyrus\u003c/em\u003e covered stents (Biotronik, Berlin, Germany) were placed from the ostial LM to mid LAD, which finally led to the successful sealing of all leaks and restoration of TIMI 3 flow in the LAD \u003cstrong\u003e(image 8)\u003c/strong\u003e. Given an existing communication between the LM artery and the pseudoaneurysm, placement of the covered stent necessitated jailing the left circumflex (LCx) artery. An attempt to fenestrate the covered stent into the LCx was technically challenging and ultimately unsuccessful. Fortunately, the patient had a very dominant RCA and the loss of LCx flow was well tolerated, with no symptomatic or hemodynamic consequences.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eOutcome and follow up\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe following day, a repeat TTE confirmed the presence of a thrombus forming within the PSA cavity. The previous connection seen on colour doppler between the LM and PSA was no longer present \u003cstrong\u003e(image 9).\u0026nbsp;\u003c/strong\u003e He was discharged well and stable shortly after.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eA repeat TTE done 4 months later showed complete resolution of the pseudoaneurysm cavity \u003cstrong\u003e(image 9).\u0026nbsp;\u003c/strong\u003eUnfortunately, he declined a repeat CT coronary angiogram.\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eHe was reviewed in subsequent clinic visits and was tolerating regular dialysis sessions without issues. After 1 year of being on dual anti platelet therapy (DAPT), his haemoglobin level was stable, and he had no bleeding manifestations. Given that he had multiple covered stents placed with risks of in-stent restenosis and thrombosis, he was continued on long term DAPT in addition to aggressive LDL lowering therapies with a target LDL of less than 1.4 mmol/L.\u0026nbsp;\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eIn this case, there was a clear indication to definitively treat the patient\u0026rsquo;s giant PSA given its rapid progression in size and presence of coronary steal phenomenon. Left untreated, the potential sequelae included spontaneous rupture with tamponade and LAD territory ischemia or infarction with subsequent malignant arrhythmias. Given its rarity and complexity, a HEART team discussion was imperative to explore management options before embarking on the procedure. Furthermore, acquiring comprehensive information on the size and location of the PSA through multi-modality imaging also proved essential in pre-procedural planning.\u003c/p\u003e\n\u003cp\u003eThe successful use of covered stents for percutaneous closure of coronary PSAs has been documented in case reports. Other proposed management options include the deployment of coils. In our case, however, given the size and extent of the PSA, along with multiple communication sites, achieving a complete seal with coils would be technically unfeasible. Furthermore, the risk of coil embolization into the LM or LAD will lead to more detrimental consequences.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eHence, the team decided on percutaneous intervention with covered stent placement. The strategy for PCI to the giant LM PSA was adapted from bailout techniques in PCI of LM coronary perforations. The drawback of LM covered stenting is the potential for jailing of side branches; in this case the circumflex artery (LCx). Furthermore, we acknowledge the long-term thrombotic and in-stent restenosis risks of deploying multiple covered stents. To mitigate this, the patient was placed on aggressive LDL lowering therapies and long term DAPT as tolerated.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eDespite meticulous pre-procedural planning, we were still faced with the unexpected challenge of plugging multiple leaks along the entire length of the LM to mid-LAD. Initially, it was believed that there was one \u0026ldquo;neck\u0026rdquo; originating from the LM-LAD junction, as confirmed on both TTE and CTCA. However, it was later understood in retrospect that, due to the lack of contrast flow into the proximal-mid LAD resulting from the coronary steal phenomenon, the more distal leaks beyond the level of LM could not be detected on CTCA. This could only be postulated based on IVUS findings and confirmed via GEC-assisted contrast injections. Nonetheless, we remained steadfast in the strategy of covered stenting and sealed all leaks. The presence of an organising thrombus within the PSA cavity, with a lack of colour Doppler flow 1-day post-procedure, was reassuring that the procedure was successful.\u003c/p\u003e\n\u003cp\u003eCauses of coronary PSAs include trauma to the vessel wall during PCI, inflammation, infection and external trauma. While our patient had active MSSA bacteraemia, the acute onset of NSTEMI with cardiogenic shock necessitated urgent intervention rather than deferring until the bacteraemia was adequately treated. \u0026nbsp; Considering \u003cem\u003eS. Aureus\u003c/em\u003e is the most common pathogen in documented cases of coronary stent infections, and the anatomically extensive involvement (suggesting the pseudoaneurysm may indeed be a healed abscess), it supports our postulation that the presence of multiple leaks along the LM-LAD could have been due to an infected coronary stent, resulting in weakening of the adjacent vessel wall. Alternatively, substantial mechanical trauma, in the form of deep coronary dissections during the index PCI, may have contributed to the formation of the PSA.\u003c/p\u003e"},{"header":"Conclusion","content":"\u003cp\u003eWhile coronary PSAs are already an uncommon complication post-PCI, giant PSAs are exceedingly rare. The available evidence reveals that surgery was the primary treatment modality. We present a case of an 8.3 x 7.4 cm coronary PSA that was successfully treated percutaneously with covered stents. This case adds another layer of complexity in that the operators were not only dealing with a giant PSA but one with multiple leaks/necks to be addressed. However, owing to meticulous pre-procedural strategizing with the HEART team and information from multi-modality imaging, the operators successfully defused the ticking time bomb. This case illustrates that PCI can be a viable and less invasive alterative to surgery for the treatment of giant PSAs.\u003c/p\u003e"},{"header":"Declarations","content":"\u003col\u003e\n \u003cli\u003eEthics approval and consent to participate \u0026ndash; Not applicable\u003c/li\u003e\n \u003cli\u003eConsent for publication \u0026ndash; informed consent has been obtained by the patient for his clinical details to be published in this case report\u003c/li\u003e\n \u003cli\u003eAvailability of data and materials \u0026ndash; Not applicable\u0026nbsp;\u003c/li\u003e\n \u003cli\u003eCompeting interests \u0026ndash; The authors declare that they have no competing interests\u0026nbsp;\u003c/li\u003e\n \u003cli\u003eFunding \u0026ndash; Not applicable\u003c/li\u003e\n \u003cli\u003eAuthors \u0026lsquo;contributions \u0026ndash; AAH was the primary operator for the case and wrote the report. RL was the supervisor and co-operator for the case and vetted the report. AAS contributed by performing the literature review to supplement the case.\u0026nbsp;\u003c/li\u003e\n \u003cli\u003eAcknowledgements \u0026ndash; Not applicable\u0026nbsp;\u003c/li\u003e\n\u003c/ol\u003e"},{"header":"References","content":"\u003col\u003e\n \u003cli\u003eSvante Gersch, Hassina Baraki, Karl Toischer, Progression and interventional therapy of a coronary pseudoaneurysm: a case report, \u003cem\u003eEuropean Heart Journal - Case Reports\u003c/em\u003e, Volume 7, Issue 1, January 2023, ytac478, https://doi.org/10.1093/ehjcr/ytac478\u003c/li\u003e\n \u003cli\u003eSharma R, Ruia AV. A case report of pseudoaneurysm of coronary artery within a month of percutaneous coronary intervention. \u003cem\u003eEur Heart J Case Rep\u003c/em\u003e. 2022;6(5):ytac175. Published 2022 Apr 21. doi:10.1093/ehjcr/ytac175\u003c/li\u003e\n \u003cli\u003eTakagi, Kensuke et al (2023). Bail-Out Techniques in Percutaneous Intervention for Ellis Grade III Coronary Perforation in Left Main Distal Bifurcation Lesions, JSCAI, Volume 2, Issue 3, 100609\u003c/li\u003e\n \u003cli\u003eElieson M, Mixon T, Carpenter J. Coronary stent infections: a case report and literature review. \u003cem\u003eTex Heart Inst J\u003c/em\u003e. 2012;39(6):884-889.\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":true,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"bmc-cardiovascular-disorders","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"bcar","sideBox":"Learn more about [BMC Cardiovascular Disorders](http://bmccardiovascdisord.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/bcar/default.aspx","title":"BMC Cardiovascular Disorders","twitterHandle":"BMC_series","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"Coronary pseudoaneurysm, percutaneous coronary intervention","lastPublishedDoi":"10.21203/rs.3.rs-8999186/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-8999186/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eBackground\u003c/p\u003e\n\u003cp\u003eGiant coronary pseudoaneurysms (PSAs) are extremely rare and typically managed surgically. Our case demonstrates an alternative approach with percutaneous intervention using covered stents.\u003c/p\u003e\n\u003cp\u003eCase Summary\u003c/p\u003e\n\u003cp\u003eA 62-year-old male underwent percutaneous coronary intervention (PCI) to the left main (LM) and left anterior descending (LAD) arteries for non-ST elevation myocardial infarction (NSTEMI) complicated by cardiogenic shock in the setting of concurrent Methicillin-Sensitive Staphylococcus Aureus (MSSA) bacteraemia. During staged PCI to the right coronary artery (RCA), a relook angiogram revealed a giant LM-LAD PSA with coronary steal phenomenon. The PSA was confirmed on multi-modality cardiac imaging and treatment with covered stents was performed successfully.\u003c/p\u003e\n\u003cp\u003eDiscussion\u003c/p\u003e\n\u003cp\u003eThis showcases the importance of multi-modality imaging and a multidisciplinary approach in managing an unusual presentation of coronary PSA. The use of covered stents for treatment is feasible and allowed successful treatment of the giant PSA, avoiding potentially catastrophic complications.\u003c/p\u003e\n\u003cp\u003eTake home messages\u003c/p\u003e\n\u003cp\u003eCoronary PSAs are rare and associated with fatal complications. PCI with covered stents is a viable treatment option.\u003c/p\u003e","manuscriptTitle":"Defusing a ticking time bomb – percutaneous intervention for a giant coronary pseudoaneurysm","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2026-03-23 10:17:45","doi":"10.21203/rs.3.rs-8999186/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2026-04-06T13:08:04+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-04-04T05:43:52+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-03-26T15:50:26+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"51115365181485062596396630740428182670","date":"2026-03-26T15:32:26+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"173626587072725860161478336263302367196","date":"2026-03-21T02:36:12+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"119795770387925354678002844004649166342","date":"2026-03-20T21:43:45+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-03-19T10:23:15+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"15695527084402058235757334786378756671","date":"2026-03-19T09:40:08+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2026-03-19T00:12:55+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2026-03-19T00:07:28+00:00","index":"","fulltext":""},{"type":"editorInvited","content":"","date":"2026-03-10T11:31:29+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2026-03-09T19:37:54+00:00","index":"","fulltext":""},{"type":"submitted","content":"BMC Cardiovascular Disorders","date":"2026-03-05T14:41:33+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"bmc-cardiovascular-disorders","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"bcar","sideBox":"Learn more about [BMC Cardiovascular Disorders](http://bmccardiovascdisord.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/bcar/default.aspx","title":"BMC Cardiovascular Disorders","twitterHandle":"BMC_series","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"4607a054-ca57-43fc-8075-d0dab9572b29","owner":[],"postedDate":"March 23rd, 2026","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"under-review","subjectAreas":[],"tags":[],"updatedAt":"2026-05-07T09:39:00+00:00","versionOfRecord":[],"versionCreatedAt":"2026-03-23 10:17:45","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-8999186","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-8999186","identity":"rs-8999186","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}