Unusually Delayed Presentation of Pulmonary Vein Stenosis After Atrial Fibrillation Ablation

Abstract

Severe pulmonary vein stenosis may occur following catheter ablation of atrial fibrillation. Symptoms usually appear within a few months. It is often misdiagnosed due to symptoms that mimic more frequent pathologies, and there is frequently a long delay between initial symptoms and diagnosis. A 50-year-old man presented with hemoptysis after having undergone catheter ablation for atrial fibrillation three and six years prior. Diagnosis of the cause was difficult and involved a number of exams and erroneous initial hypotheses. Pulmonary vein stenosis was ultimately confirmed by transesophageal echocardiography. Balloon angioplasty of the affected pulmonary vein was performed, with initial clinical improvement but later restenosis. The patient then underwent surgical reconstruction of the vein. The three-year interval between catheter ablation and his presentation with symptoms is unusually long. Clinicians should retain pulmonary vein stenosis in their differential diagnosis of hemoptysis in patients having undergone pulmonary vein isolation for atrial fibrillation, even beyond the first year after catheter ablation.

Introduction

Pulmonary vein stenosis is a potential complication of catheter ablation of atrial fibrillation. It occurs when scar tissue from the ablation procedure partially obstructs the ostium of one or more pulmonary veins. Severe stenosis is generally defined as a reduction of luminal diameter at the ostium of more than 70% [1]. It is rare; in modern cohorts, the incidence is estimated at 0.07% [2]. The first clinical manifestations of severe stenosis usually appear within a few months following the ablation; delayed presentations beyond one year are exceptional. In the largest cohort of patients requiring intervention, the delay was 4.0 +/- 3.0 months [3]. In another cohort, the delay was 5 months (interquartile range 4-9 months) [4]. Symptoms and signs include dyspnea, cough, hemoptysis, chest pain, pneumonia, or recurring pneumonia and chest pain. Due to this aspecific presentation, which can mimic more frequent pathologies, pulmonary vein stenosis is often misdiagnosed, and there is frequently a long delay between initial symptoms and diagnosis. Screening for pulmonary vein stenosis after atrial fibrillation ablation is not recommended by expert consensus statements, and imaging is not performed unless the patient becomes symptomatic [1].

Case presentation

A 50-year-old man presented to the emergency department in November 2024 with hemoptysis as his chief complaint. His past medical history included active smoking as well as radiofrequency catheter ablation of atrial fibrillation in October 2018 and October 2021, six years and three years prior to his presentation in the emergency department. The first procedure was initial pulmonary vein isolation (PVI) alone; the second procedure was an enlarged PVI with no additional ablation targets. Both ablation procedures had used radiofrequency point-by-point ablation following CLOSE protocol criteria, with an AI (ablation index) of 450 on the anterior wall and 300 on the posterior wall. The Biosense Carto System (Biosense Webster, Irvine, CA) was used, and the electro-anatomical map had been merged with the cardiac scan. No intracardiac echocardiography had been used.

The patient took no medication. He complained only of one prior episode of hemoptysis, in June 2024; he had swallowed a cherry pit, and the hemoptysis had then resolved spontaneously, so no further workup was performed at that time.

A diagnostic workup was performed. A fibroscopy of the pharynx and larynx was normal. A contrast-enhanced computed tomography (CT) scan of the thorax showed multiple nodular lesions surrounded by a halo of ground-glass lesions in the upper left pulmonary lobe (see Figure 1). No pulmonary vein stenosis was observed at this time. The working diagnosis was either an infectious cause or a pulmonary embolism. No thrombus was conclusively seen. Both hypotheses were later deemed substantially less likely by D-dimer levels below the institutional cutoff and only minimal inflammatory syndrome in the blood work (white blood cell count 7.58/nL; neutrophil count 4.93/nL; C-reactive protein 16.2 mg/L). A bronchoscopy was performed; the left main bronchus showed traces of blood. On a light cough, a substantial hemorrhage was caused, flooding the left bronchial tree with blood; 100 mL was aspirated. (Culture of the aspiration would later prove unremarkable, with small quantities of commensal microbes). This prompted a second CT scan to formally exclude a pulmonary embolism; stenosis and opacification of the left superior pulmonary vein were observed. From these images, a working diagnosis of pulmonary vein stenosis was put forward.

Figure 1. Contrast-enhanced chest computed tomography on initial presentation.

Multiple nodular lesions surrounded by a halo of ground-glass can be seen (arrows) in the left upper lobe. In pulmonary vein stenosis, this is caused by lung edema resulting from elevated venous pressure in the territory drained by that vein [5].

A transesophageal echocardiogram was performed. The ostium of the left superior pulmonary vein was stenotic, with a hyperechogenic zone at the ostium, corresponding to scar tissue formed after the ablation procedure, and a vena contracta of 2.2 mm (see Figure 2). The vein distal to the ostium was of normal diameter (11 mm), implying a stenosis of 80%; the stenosis is quantified in Table 1. The other pulmonary veins were observed to be normal. The right heart cavities were mildly dilated (right ventricular basal diameter 43 mm, right atrium surface 19 cm², normal movement of the interventricular septum); there was no tricuspid regurgitation with which to estimate the pulmonary arterial pressure. A retrospective analysis of the electrophysiological cartography data from the ablations three and six years prior showed that no stenosis was present at the time.

Table 1. Echographic parameters of the left superior pulmonary vein before and after balloon angioplasty.

The diameters are measured by the vena contracta.

	Ostial diameter	Peak velocity	Mean gradient
Before angioplasty	2.2 mm	2.0 m/s	13 mmHg
After angioplasty	7.0 mm	1.7 m/s	10 mmHg

Figure 2. Transesophageal ultrasound showing severe left superior pulmonary vein stenosis.

(A) Biplane view of the vein, showing stenosis and a hyperechogenic zone at the ostium, corresponding to scar tissue that formed after the ablation procedure. (B) Color Doppler view showing acceleration and turbulent flow at the ostium. The ostium was measured at 2.2 mm and the distal portion at 11 mm, an 80% reduction in diameter.

A percutaneous angioplasty of the pulmonary vein stenosis was performed, guided using simultaneous fluoroscopy, cartography, and transesophageal echocardiography. The echographic measures of the stenosis improved after angioplasty (see Table 1). Due to the substantial difference in diameter between the ostium and the rest of the vein, it was decided not to place a stent.

A thoracic CT performed the next day showed a regression in the size of the previously seen ground-glass lesions, suggesting they were indeed due to pulmonary vein stenosis. The ostium of the vein, however, was measured at 3 mm, suggesting early elastic recoil.

At the 6-week follow-up after the procedure, the patient reported marked improvement in dyspnea and no recurrence of hemoptysis. The patient was not troubled by the possible diagnostic delay of 5 months from the first symptoms; he remained convinced that the hemoptysis at 32 months was entirely caused by the cherry pit. A transesophageal echocardiogram demonstrated a return to the initial transostial velocity and a recurrence of the stenosis.

The following month, he consulted at another clinic for further recurring hemoptysis, where he underwent surgical reconstruction of the vein with a patch of bovine pericardium by lateral thoracotomy. There were no serious postoperative complications. He was free of recurring hemoptysis at a checkup one year after the intervention. Figure 3 provides a timeline of key events.

Figure 3. A timeline of key events.

AF: Atrial fibrillation

Discussion

The patient presented with spontaneously resolutive hemoptysis 32 months after the PVI procedure, after having swallowed a cherry pit. At the time, this diagnosis was accepted, and no further workup was performed. There is a significant probability that this was in fact the first clinical manifestation of the stenosis. This represents a probable missed diagnostic opportunity; had CT angiography or transesophageal echocardiography been performed at this time, the patient could potentially have been diagnosed and treated much sooner. His smoking history should also have aroused suspicion: in addition to accelerating vascular remodeling, smoking-related pathology causing hemoptysis, including malignancy and bronchitis, should have been excluded.

The patient had a CT finding of nodular lesions with a ground-glass halo. This is caused by lung edema resulting from elevated venous pressure in the territory drained by that vein [5]. Taken with normal D-dimer levels in a patient having undergone PVI, this should elicit suspicion of pulmonary vein stenosis.

Typically, severe pulmonary vein stenosis after catheter ablation of atrial fibrillation manifests in a matter of months following the procedure [3,4]. In the present case, the patient’s symptoms manifested about three years after his catheter ablation: 32 months to the first spontaneously resolving hemoptysis episode that was attributed to the cherry pit, or 37 months to the second bout of hemoptysis. In either situation, this is an unusually long time, among the longest described in the literature. Indeed, in patients having undergone catheter ablation in the past 10 years, there are very few cases of pulmonary vein stenosis described where the symptoms appeared so long afterward. Table 2 presents a list of other cases with remarkably long intervals before symptom onset.

Table 2. Reports of unusually long intervals between catheter ablation of atrial fibrillation and symptomatic pulmonary vein stenosis.

*The precise chronology of the first symptoms and pleural effusions in Kind et al. 2021 is not specified.

**The patient suffered from pre-existing heart failure, so the date of the first symptoms due to pulmonary vein stenosis specifically cannot be determined.

Reference	Delay from most recent PVI to first symptoms	Symptoms and signs
Talmor et al. 2021 [6]	18 months	Cough, fever, dyspnea
Akiki et al. 2022 [7]	2 years	Cough, hemoptysis
Kind et al. 2021 [8]	3 years*	Dyspnea, recurrent pleural effusions
Tseng et al. 2023 [9]	50 months	Dyspnea, productive cough, chest pain, hemoptysis
Pang et al. 2025 [10]	8 years**	Dyspnea

The existence of such reports raises the question of the need for systematic screening even beyond one year after PVI to detect initially asymptomatic pulmonary vein stenosis. That being said, the complication itself is rare, and such a delayed presentation is yet rarer. There are potential harms of screening exams such as CT angiography, ventilation-perfusion imaging by scintigraphy, or transesophageal echocardiography; we believe it is probably appropriate to limit investigations to patients who exhibit characteristic symptoms, as is current clinical practice. Even then, such an approach is difficult; dyspnea, cough, pneumonia and chest pain are frequent in the patient population that develops atrial fibrillation, and these are most often linked to the underlying cardiac conditions and comorbidities without being mediated by pulmonary vein stenosis.

Conclusions

Severe pulmonary vein stenosis is a potential complication of catheter ablation of atrial fibrillation. The symptoms overlap with those of more frequent pathologies, causing difficulties and delays in diagnosis. The present case joins a small but growing literature of presentations with symptomatic pulmonary vein stenosis two years or more after the most recent procedure.

Clinicians should retain pulmonary vein stenosis in their differential diagnosis of dyspnea, cough, chest pain, pneumonia, and, in particular, hemoptysis in patients who have undergone PVI for atrial fibrillation. This case and others like it demonstrate the importance of remaining mindful of this possibility even more than a year after the catheter ablation procedure.