Key Teaching Points
Pulmonary vein aneurysms are rare primary or secondary defects that can be found in
the left atrium.
Atrial tachycardia and atrial fibrillation can be triggered from a pulmonary vein
These arrhythmias can be ablated or the aneurysm can be excised surgically.
We report a case of focal atrial tachycardia and atrial fibrillation that resulted
from a pulmonary vein aneurysm, a rare anatomic condition that presents difficulties
in successful treatment.
A 30-year-old pregnant woman (30th week of pregnancy, G1/P0), was referred to our
department in 2006 for evaluation of symptomatic palpitations with increased frequency
and duration since the beginning of her pregnancy. Her medical history was otherwise
uneventful. Clinical examination and laboratory investigations were normal. The rest
electrocardiogram showed a normal sinus rhythm. The 7-day Holter showed daily episodes
of supraventricular tachycardia at 270 beats/min, which could be induced during stress
testing (Figure 1A and B). The transthoracic echocardiography displayed no structural
heart disease. Owing to pregnancy, more invasive investigations were deferred. The
patient was reassured of the benign course of the arrhythmia and advised to take metoprolol
50 mg as “pill in the pocket” therapy.
Electrocardiograms during sinus rhythm, atrial tachycardia (AT), and atrial fibrillation
(AF). A: Normal SR, 78 beats/min (bpm). B: AT (short RP′) at 270 bpm during an exercise
test prior to the radiofrequency ablation, hemodynamically stable, no effect of adenosine
administration. C: Focal AT during the ablation procedure, successfully ablated at
the right inferior pulmonary vein aneurysm. D: Paroxysmal AF, treated with pulmonary
Two years later, she returned to our center owing to a recurrence of the arrhythmia.
An electrophysiological examination was subsequently carried out and demonstrated
atrial tachycardia of septal or left-sided localization without any signs of accessory
pathway or slow pathway, suggesting an atrioventricular nodal reentry tachycardia
or atrioventricular reentrant tachycardia. Because of the difficulty of triggering
the arrhythmia and the lack of electroanatomic mapping system, no ablation was performed
and medical therapy consisting of bisoprolol 1.25 mg daily and flecainide 100 mg twice
daily was initiated.
In 2009, a second electrophysiological examination using electroanatomic mapping was
performed and a focal ectopic atrial tachycardia (Figure 1C) of the right inferior
pulmonary vein (RIPV) was mapped and treated (Supplemental Figure). During the procedure,
an episode of paroxysmal atrial fibrillation was also observed (Figure 1D). During
the following months, the patient completed a second pregnancy, during which a slight
increase in the frequency of the palpitations was noted.
The following 3 years were initially uneventful, but new supraventricular arrhythmias
were more frequently triggered, including paroxysmal atrial fibrillation. Oral anticoagulation
with rivaroxaban was introduced and a pulmonary vein isolation (PVI) was planned with
prior heart computed tomography angiography.
This examination revealed an aneurysm of the RIPV measuring 29 × 25 mm (Figure 2).
A cautious PVI was performed successfully at the venous side of the aneurysm, using
contact force < 10g (Figure 3A). Afterward, no arrhythmia was inducible. However,
a relapse prompted the decision to switch the antiarrhythmic therapy to dronedarone.
Computed tomography (CT) and magnetic resonance (MR) images of the pulmonary vein
aneurysm. Illustrates stable dimensions of the right inferior pulmonary vein aneurysm
over 3 years (multidetector CT on the left, MR angiography on the right).
Electroantomic mapping radiofrequency ablation in 2013 and 2014. A: Prior acquired
cardiac computed tomography angiography images are integrated and merged into the
electroanatomic mapping system (CARTO 3, Biosense Webster, Diamond Bar, CA). Red points
are ablation points. Ablation is performed at the venous side (arrows) of the aneurysm
of the right inferior pulmonary vein. B: Activation map using CARTO 3 (Biosense Webster)
of a focal AT (earliest focal spread from the red area within the aneurysm) that was
ablated at the earliest sharp and fragmented bipolar electrogram (small arrow). Redo
pulmonary vein isolation was performed using Visitag. The right inferior pulmonary
vein was ablated on the venous side of the aneurysm.
A further relapse of a left focal atrial tachycardia from the RIPV aneurysm was treated
together with a redo PVI, by means of radiofrequency ablation in 2014 (Figure 3B).
A cardiac magnetic resonance imaging performed 3 years after the computed tomography
angiography indicated a stable diameter of the pulmonary vein aneurysm (PVA). The
patient has since remained asymptomatic without antiarrhythmic drugs.
Pulmonary vein aneurysms are rare defects of the vascular wall, first described by
Pucher in 1843.
Most PVAs (80%) are thought to be congenital, often associated with other congenital
diseases or with arteriovenous malformations. A small minority of PVAs are acquired,
secondary to significant mitral regurgitation
or trauma. Although most of them are benign and incidentally discovered, cases have
been described with complications such as hemoptysis, stroke,
and even sudden death. These aneurysms can trigger supraventricular arrhythmia and
can be treated by ablation.4, 5 Theoretically, high contact and ablation could also
create an aneurysm. We cannot exclude this possibility, since imaging was only performed
after the first left-sided ablation. PVAs are often difficult to ablate and surgical
excision of the aneurysm can be performed.3, 6 It is important for electrophysiologists
to be aware of this anatomic anomaly. Most centers perform PVI without image guiding
prior to or during the case. In case of anatomic anomalies, imaging can, however,
be very useful to help understand the arrhythmia and guide the treatment.