Iatrogenic Left Main Coronary Artery Stenosis Following Interventional and Surgical Procedures: A Literature Review

Abstract

Iatrogenic left main coronary artery (LMCA) stenosis is a rare but life-threatening complication that may occur after percutaneous coronary intervention (PCI) or cardiac valve surgery. While initially uninvolved, the LMCA can develop significant stenosis months after manipulation of other coronary vessels, raising diagnostic and therapeutic challenges. This review aims to synthesize existing case reports and clinical experiences regarding the development of iatrogenic LMCA stenosis in patients with no prior LMCA lesions, focusing on procedural causes and subsequent treatment strategies. A comprehensive review of the literature identified and analyzed a total of 14 publications comprising 8 multi-patient case series, 4 single case reports, and 1 retrospective cohort were identified, who developed iatrogenic LMCA stenosis following PCI or aortic valve surgery. Mechanisms, clinical presentations, diagnostic approaches, and outcomes of various treatment modalities were analyzed. The most common mechanisms included catheter-induced trauma, balloon overdistension, and ostial cannulation during valve surgery. Clinical presentation ranged from recurrent angina to cardiogenic shock. Treatment strategies included coronary artery bypass grafting, percutaneous coronary angioplasty with stenting, and in select hemodynamically stable patients, conservative medical therapy. PCI was often reserved for high-risk surgical patients or when rapid revascularization was essential. Iatrogenic LMCA stenosis should be considered in patients presenting with angina after coronary or valvular interventions, especially in the absence of prior LMCA disease. Early recognition through angiography and appropriate selection of revascularization strategy, surgical or percutaneous, is critical for optimizing outcomes.

Introduction

Iatrogenic complications have become increasingly recognized in the context of the expanding use of interventional cardiology procedures. Among these, left main coronary artery (LMCA) stenosis represents a rare but potentially life-threatening complication. Particularly concerning are cases in which patients with previously normal LMCA anatomy develop significant stenosis following percutaneous coronary intervention (PCI) performed on other coronary vessels.

In addition to percutaneous interventions, iatrogenic LMCA stenosis has also been reported after various cardiac surgical procedures, most notably aortic valve replacement (AVR). During AVR, the proximity of the LMCA ostium to the aortic annulus renders it vulnerable to direct or indirect injury. Several mechanisms have been proposed, including mechanical trauma from antegrade cardioplegia cannulas, coronary ostial perfusion catheters, or suture placement near the left coronary ostium. Furthermore, post-operative inflammatory reactions and fibrointimal proliferation secondary to endothelial injury may contribute to delayed LMCA narrowing.

The pathogenesis of iatrogenic LMCA stenosis is typically attributed to direct mechanical trauma from guiding catheters, balloon overdistension causing arterial wall injury, or ostial cannulation during valve Surgery.[1,2] The onset of clinical symptoms generally occurs within a time frame of weeks to months post-procedure, most frequently manifesting as recurrent angina, ventricular arrhythmias, or myocardial infarction.

Diagnosis is typically made by coronary angiography upon recurrence of symptoms. Management strategies vary depending on the patient’s clinical stability, comorbidities, and anatomical considerations. While coronary artery bypass grafting (CABG) remains the standard treatment, PCI has shown promise in high-risk surgical patients or those who decline surgery.[3]

In this review, we summarize the existing literature on cases of iatrogenic LMCA stenosis that developed after coronary or valvular interventions in patients with no prior LMCA disease. We examine the underlying mechanisms, clinical presentations, and treatment approaches, with the goal of increasing awareness of this serious complication and guiding optimal management strategies.

Materials and Methods

Data Sources and Search Strategies

This systematic review was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines and the Cochrane Handbook for Systematic Reviews of Interventions (version [insert version, e.g., 6.4]). A comprehensive search of the literature was performed using the PubMed database without restrictions on publication date or language. The following search terms were used in various combinations with Boolean operators: “iatrogenic,” “left main coronary artery,” “LMCA,” “stenosis,” “percutaneous coronary intervention,” “PTCA,” “aortic valve surgery,” “heart valve replacement,” and “catheter-induced injury.”

In addition, reference lists of included articles were manually screened to ensure a comprehensive search. Grey literature and conference abstracts were not included in the analysis.

Eligibility and Criteria

Studies were eligible for inclusion if they reported one or more cases of newly developed iatrogenic LMCA stenosis occurring after PCI or aortic valve surgery in patients with no pre-existing LMCA disease. Articles needed to provide angiographic or clinical evidence of LMCA involvement and include diagnostic approaches and treatment strategies. Exclusion criteria included studies describing spontaneous or atherosclerotic LMCA stenosis unrelated to interventional procedures, those lacking sufficient clinical detail or outcome data, and non-clinical publications, such as editorials, expert opinions, or reviews without original case data. Only human studies were included in the analysis.

Data Characterization, Summary, and Synthesis

For each included article, we extracted information on study type (case report or series), patient demographics, index procedure type (PCI or aortic valve surgery), time to symptom onset, clinical presentation, diagnostic methods, and proposed mechanism of LMCA injury, treatment strategy, and outcomes.

Due to the heterogeneity and descriptive nature of the included reports, we did not perform a meta-analysis or pooled quantitative synthesis. No formal risk of bias assessment was conducted, as most included studies were single-case reports with limited methodological data. Instead, we summarized and categorized the clinical characteristics and management strategies in a qualitative synthesis.

Results

A total of 14 publications comprising 8 multi-patient case series, 4 single case reports, and 1 retrospective cohort were identified who developed iatrogenic LMCA stenosis after PCI or aortic valve surgery, despite having previously normal LMCA anatomy.

The onset interval from the index procedure to the development of symptoms ranged from 3 weeks to 19 months (mean: 4.7 months). The most frequent presentation was angina pectoris (reported in 12 patients, 67%), followed by acute coronary syndrome or myocardial infarction (4 patients, 22%) and heart failure or arrhythmia (2 patients, 11%).

Coronary angiography was the primary diagnostic tool in all cases, while intravascular ultrasound or computed tomography (CT) was used in recent reports for detailed assessment of ostial involvement.

Regarding management, CABG was performed in 10 cases (56%), PCI in 6 cases (33%), and conservative medical management in 2 cases (11%).

Across all reports, the dominant pathophysiological mechanism was catheter- or cannulation-induced endothelial trauma followed by fibrointimal proliferation, resulting in delayed luminal narrowing.

Mechanisms and Etiology

Multiple mechanisms of injury have been described in the literature. A summary of the reported mechanisms, associated procedures, and corresponding treatment strategies from the relevant literature is presented in Table 1. Table 2 summarizes the clinical presentations, timing of symptom onset, and diagnostic modalities reported across the included cases of iatrogenic LMCA stenosis.

Table 1. A summary of the reported mechanisms, associated procedures, and corresponding treatment strategies from the relevant literature is presented

Table 2. Summarizes the clinical presentations, timing of symptom onset, and diagnostic modalities reported across the included cases of iatrogenic LMCA stenosis

Discussion

Iatrogenic LMCA stenosis is an uncommon but serious complication observed after interventional procedures, such as PCI, PTCA, and cardiac valve surgery. Although the LMCA is often not directly manipulated in these procedures, a growing number of case reports suggest that trauma related to catheter use, balloon inflation, or surgical perfusion techniques can cause the delayed onset of LMCA narrowing even in patients with no prior LMCA disease.

In PCI-related cases, inadvertent trauma from guiding catheters or high-pressure balloon dilation of proximal LAD or LCx segments may cause retrograde damage extending into the LMCA, resulting in intimal injury, and ultimately fibrosis.[1,4,5] Similarly, repeated PCI in complex lesions or bifurcation stenting with “kissing balloon” techniques have been associated with LMCA involvement, especially when backup catheters are used in anatomically small vessels.[6]

In surgical cases, such as valve replacements, direct ostial cannulation during antegrade cardioplegia has been implicated in LMCA damage. Daniel et al.[7] reported a case of LMCA ostial stenosis developing four months after surgical AVR, likely caused by mechanical trauma from antegrade cardioplegia cannulation and high perfusion pressure, resulting in endothelial injury and subsequent fibrointimal hyperplasia leading to progressive luminal narrowing. AVR, in particular, carries this risk due to proximity to the coronary ostia. Perfusion catheters, especially rigid or oversized ones, can exert mechanical pressure on the LMCA ostium, leading to endothelial trauma and later fibrointimal proliferation.[2,8,9]

Similarly, in transcatheter aortic valve implantation (TAVI), coronary obstruction may occur through distinct but primarily mechanical mechanisms, rather than intimal injury. In most cases, obstruction results from displacement of bulky or calcified native leaflets toward the coronary ostia during valve deployment, or occlusion caused by low coronary ostial height and narrow sinuses of Valsalva, which restrict coronary outflow. Less frequently, obstruction may result from the interaction between the transcatheter valve frame or prosthetic leaflets and the coronary orifice, especially in valve-in-valve procedures.[10–12] These mechanisms typically produce acute coronary obstruction during or immediately after valve implantation, often manifesting as sudden hemodynamic collapse or ST-segment elevation. However, late coronary obstruction after TAVI reported in the Spanish TAVI Registry may develop weeks or months later due to delayed prosthetic leaflet malposition or progressive thrombus and neointimal proliferation around the coronary ostium.[10] This pathophysiology differs substantially from the delayed fibrointimal proliferation related LMCA stenosis observed after surgical valve replacement or percutaneous interventions in our review.

Quiret et al.[13] described four patients who developed LMCA or nearby stenoses shortly after PTCA, attributing the mechanism to intimal damage caused by the guiding catheter or distal hardware, such as the balloon or guidewire. These injuries led to fibrotic healing and progressive luminal narrowing, highlighting the procedural sensitivity of the LMCA even in interventions targeted at its branches.

Dibie et al.[14] reported five cases of LMCA stenosis diagnosed 3–12 months after prior angioplasty, again in patients without prior LMCA involvement. Their study emphasized the rarity but significance of this phenomenon (0.2–1.7% incidence), attributing it to traumatic manipulation during PTCA and comparing their findings with earlier reports on valve surgery–related injury.

Most patients present within 1–6 months of the index procedure with symptoms, such as exertional angina, unstable angina, or myocardial infarction. In some cases, patients may experience sudden hemodynamic collapse due to acute LMCA occlusion.[15] Repeat coronary angiography is the gold standard for diagnosis, although CT angiography has shown promise in early detection, especially in post-operative cases.[15]

Management must be individualized based on clinical stability, extent of stenosis, and surgical candidacy. A proposed diagnostic and therapeutic decision-making algorithm is presented in Figure 1 to aid clinicians in managing suspected cases of iatrogenic LMCA stenosis following coronary or valvular interventions. CABG remains the preferred option for most patients, especially those with multivessel disease or high-grade LMCA stenosis.[9,16] In Akchurin’s retrospective cohort, all patients with newly developed LMCA stenosis after PCI were successfully treated with CABG, suggesting this remains a reliable and effective strategy for complex cases.[6] However, several cases have demonstrated successful treatment with PCI and drug-eluting stents, particularly in patients at high surgical risk or with isolated LMCA lesions.[3,17]

Figure 1. A proposed diagnostic and therapeutic decision-making algorithm is presented.

Study Limitations

The primary limitation of this review lies in its dependence on case reports and small series, which inherently limit generalizability and increase the risk of publication bias. Inconsistent definitions, incomplete procedural data, and the exclusion of non-indexed or non-English studies may further limit the robustness and comparability of findings.

Conclusion

Iatrogenic LMCA stenosis is a rare but serious complication that may develop weeks to months after PCI or valve surgery, even in patients with initially normal LMCA anatomy. It is primarily caused by catheter trauma, balloon overinflation, or ostial cannulation. Non-specific symptoms, such as recurrent angina require high clinical suspicion and early angiographic evaluation. While CABG remains the standard treatment, PCI is a valid alternative in select patients, and conservative management may be appropriate in stable cases. Early recognition and individualized treatment are essential for improving outcomes.

Our review reinforces the importance of preventive procedural techniques, early recognition, and individualized treatment planning in managing this uncommon but serious complication. Further prospective studies are needed to better understand the true incidence, risk predictors, and optimal long-term management of iatrogenic LMCA stenosis.

Cite This Article: Bozkurt B, Yavuz S, Kuş MK, Memetoğlu ME. Iatrogenic Left Main Coronary Artery Stenosis Following Interventional and Surgical Procedures: A Literature Review. Koşuyolu Heart J 2026;29(1):76–80.

Externally peer-reviewed.

Concept – B.B., S.Y.; Design – B.B., S.Y.; Data collection/processing – B.B., M.K.K.; Analysis/interpretation – B.B., M.E.M.; Drafting the manuscript – B.B., S.Y.; Critical revision – M.K.K., M.E.M.

All authors declared no conflict of interest.

No AI technologies utilized.

The authors declared that this study received no financial support.

References

1. Bashour TT, Hanna ES, Edgett J, Geiger J. Iatrogenic left main coronary artery stenosis following PTCA or valve replacement. Clin Cardiol 1985;8:114–7.
2. Pande AK, Gosselin G. Iatrogenic left main coronary artery stenosis. J Invasive Cardiol 1995;7:183–7.
3. Martí V, Augé JM, García Picart J, Guiteras P, Ballester M, Obrador D. Percutaneous transluminal coronary angioplasty as alternative treatment to coronary artery bypass surgery in iatrogenic stenosis of the left main coronary artery. J Interv Cardiol 1995;8:229–31.
4. Wayne VS, Harper RW, Pitt A. Left main coronary artery stenosis after percutaneous transluminal coronary angioplasty. Am J Cardiol 1988;61:459–60.
5. Siddiqui MS, Hussain SMF, Hanif B. Catheter induced left main coronary artery stenosis: a rare complication of percutaneous coronary intervention. Int J Case Rep Images 2012;3:5–9.
6. Akchurin RS, Shiriaev AA, Rudenko BA, Vasil'ev VP, Vlasova ÉE, Kolegaev AS. Left main coronary artery stenosis and progression of coronary artery atherosclerosis after angioplasty and stenting in patients directed to coronary artery bypass surgery. Kardiologiia 2012;52:58–64 [Article in Russian].
7. Daniel E, El-Nayir M, Dougan T, Dutta P, Nona P. A rare complication unveiled: ostial left main stenosis post SAVR-A case report. J Investig Med High Impact Case Rep 2025;13:23247096251358675.
8. Ogawa T, Iwaya F, Ikari T, Hagiwara K, Tanji M, Sadogawa H, et al. Left main coronary artery stenosis following aortic valve replacement using a solid coronary perfusion catheter: report of two cases. Kyobu Geka 1993;46:323–6.
9. Yavuz S, Göncü MT, Sezen M, Türk T. Iatrogenic left main and proximal right coronary artery stenoses after aortic valve replacement. Eur J Cardiothorac Surg 2002;22:472–5.
10. Ojeda S, González-Manzanares R, Jiménez-Quevedo P, Piñón P, Asmarats L, Amat-Santos I, et al. Coronary obstruction after transcatheter aortic valve replacement: insights from the Spanish TAVI Registry. JACC Cardiovasc Interv 2023;16:1208–17.
11. Ribeiro HB, Nombela-Franco L, Urena M, Mok M, Pasian S, Doyle D, et al. Coronary obstruction following transcatheter aortic valve implantation: a systematic review. JACC Cardiovasc Interv 2013;6:452–61.
12. Ribeiro HB, Webb JG, Makkar RR, Cohen MG, Kapadia SR, Kodali S, et al. Predictive factors, management, and clinical outcomes of coronary obstruction following transcatheter aortic valve implantation: insights from a large multicenter registry. J Am Coll Cardiol 2013;62:1552–62.
13. Quiret JC, Remond A, Jarry G, Avinée P, Cazé F. Sténoses coronaires iatrogènes après angioplastie [Iatrogenic coronary stenosis after angioplasty]. Arch Mal Coeur Vaiss 1990;83:385–91.
14. Dibie A, Philippe F, Temkine J, Larrazet F. Iatrogenic lesions of the left main coronary artery. Arch Mal Coeur Vaiss 2002;95:781–6.
15. Funada A, Mizuno S, Ohsato K, Murakami T, Moriuchi I, Misawa K, et al. Three cases of iatrogenic coronary ostial stenosis after aortic valve replacement. Circ J 2006;70:1312–7.
16. Hamad N, Pichard AD, Oboler AA, Lindsay J. Left main coronary artery stenosis as a late complication of percutaneous transluminal coronary angioplasty. Am J Cardiol 1987;60:1183–4 .
17. Cola C, Yuste VM, Sabaté M. Left main coronary artery stenosis following surgical valve replacement: changing valvular into ischemic heart disease. J Invasive Cardiol 2009;21:E9–11.

Figure and Tables

Figure 1. A proposed diagnostic and therapeutic decision-making algorithm is presented.

Table 1. A summary of the reported mechanisms, associated procedures, and corresponding treatment strategies from the relevant literature is presented

Table 2. Summarizes the clinical presentations, timing of symptom onset, and diagnostic modalities reported across the included cases of iatrogenic LMCA stenosis