Download Infundibular Pulmonary Stenosis

Echo Rounds
Infundibular Pulmonary Stenosis
Viji Kurup, MD*
Albert Perrino, Jr., MD*
Paul Barash, MD*
Sabet W. Hashim, MD†
A
63-yr-old patient presented with a preoperative
diagnosis of aortic stenosis and pulmonary stenosis for
aortic valve (AV) replacement and possible pulmonary
valve (PV) repair. His symptoms included chest heaviness and shortness of breath. A preoperative transthoracic echocardiogram demonstrated calcified tri-leaflet AV
with severe stenosis and a peak pulmonic flow velocity of
3.7 m/s. Cardiac catheterization confirmed these findings
with a right ventricular (RV) pressure of 71/⫺3 mm Hg,
pulmonary artery (PA) pressure of 26/11 mm Hg and a
peak pulmonic gradient of 45 mm Hg. Intraoperative
transesophageal echocardiography (TEE) was performed
and the PV was interrogated in several planes. The
midesophageal (ME) RV inflow–outflow view was suboptimal due to shadowing from the calcified AV. Similarly,
the ME AV short axis (SAX) view was obtained and the
probe was gradually withdrawn to image the PA. This
view was inadequate because of bronchial interference.
Subsequently, the upper esophageal aortic arch SAX view
was obtained and the PV visualized. The leaflets were
mobile with normal morphology. Continuous wave Doppler interrogation revealed a maximum velocity of 3.2 m/s
(peak gradient of 40 mm Hg) (Fig. 1). The RV function was
assessed to be normal. To better define the etiology of the
gradient, the probe was advanced to the transgastric (TG)
midpapillary level, turned rightward and the multiplane
angle rotated to 125° to obtain the TG RV inflow–outflow
view (1). Gain settings and focus were adjusted to optimize
image acquisition. This view revealed a normal appearing
PV and a thickened infundibular septum bulging into the
RV outflow tract (RVOT) (Echo Clip 1). These findings,
consistent with subpulmonic stenosis, altered the surgical
This article has supplementary material on the Web site:
www.anesthesia-analgesia.org.
From the *Department of Anesthesiology; and †Section of Cardiothoracic Surgery, Yale University School of Medicine, New
Haven, Connecticut.
Accepted for publication November 21, 2006.
Address correspondence and reprint requests to Viji Kurup, MD,
Department of Anesthesiology, Tompkins-3, Yale University School
of Medicine, 333 Cedar St., New Haven, CT 06510. Address e-mail
to [email protected].
Copyright © 2007 International Anesthesia Research Society
DOI: 10.1213/01.ane.0000255204.39328.0b
Vol. 104, No. 3, March 2007
plan from valve repair to pulmonary arteriotomy and
examination of the RVOT and infundibular myomectomy.
After institution of cardiopulmonary bypass and AV replacement, the main PA was incised, revealing a normal
PV and bulging of the interventricular septum into the
RVOT. Other conditions that could mimic RVOT obstruction such as aneurysm of the membranous interventricular
septum and mass lesions in the RVOT were excluded by
inspection. A septal myomectomy of the RVOT was performed. (Fig. 2) Postcardiopulmonary bypass, Doppler
interrogation in the TG RV inflow–outflow view documented velocities of 2.39 m/s (peak pressure gradient 22
mm Hg).
The pathology report on the excised septum noted
cardiac myocyte hypertrophy and interstitial fibrosis.
The patient’s postoperative course was uneventful. On
postoperative day 13, a transthoracic echocardiogram
showed peak RVOT/pulmonic velocities of 1.55 m/s
(peak gradient 9.6 mm Hg).
Isolated infundibular pulmonic stenosis is an uncommon cardiac abnormality, with a reported incidence of
0.4% (2) of patients with congenital heart disease. Novel
methods of decreasing pulmonary gradient with DDD
pacing have been described in the literature (3). The
views used in a standard TEE examination may not
provide detailed morphologic and hemodynamic assessment of the RVOT and PA. The ME RV inflow– outflow
view is useful to examine the morphology of the RVOT.
However, the RVOT flow is perpendicular to the interrogating Doppler beam used to estimate velocities. Further, shadowing from a calcific AV can obscure the
RVOT. In this case, the upper esophageal aortic arch
SAX view demonstrated a morphologically normal PV,
but we were not able to visualize the RVOT. An alternative approach to visualizing right heart structures is
the TG RV inflow– outflow view. From the TG left
ventricular midpapillary SAX view, the probe is turned
rightward and the imaging array rotated to 110°–140° to
obtain a view of the right atrium, tricuspid valve as well
as the RVOT and PV (Clip 2). (1) Using this approach,
the TEE examination demonstrated a normal appearing
PV with protrusion of the septum into the RVOT, and
facilitated the diagnosis of infundibular pulmonary stenosis. Other conditions causing RVOT obstruction are
507
Figure 1. Prebypass upper esophageal aortic arch short axis view with schematic representation of the view. Continuous wave
doppler interrogation of right ventricular outflow tract (RVOT)/PA reveals maximum velocity of 3.19 m/s with peak gradient
of 40 mm Hg.
Figure 2. Post resection transgastric right ventricular inflow-outflow view showing area of resection. Schematic representation
of the view showing right atrium (RA), right ventricle (RV), pulmonary artery (PA), pulmonary valve (PV), and aorta (Ao).
protrusion of right sinus of Valsalva into the RVOT,
aneurysm of membranous ventricular septum, and intra
and extracardiac mass lesions in the RVOT such as
sarcoma. Congenital conditions such as Tetralogy of
Fallot may also be associated with this condition, and
search for other components should be conducted. This
report demonstrates the value of a comprehensive examination of the right heart to identify an uncommon
abnormality and guide surgical management.
508
Infundibular Pulmonary Stenosis
REFERENCES
1. Sreeram GM, Mark MJ. Right ventricle, right atrium, tricuspid
valve, and pulmonic valve. In: Perrino R, ed. A practical approach to transesophageal echo cardiography. Philadelphia: Lippincott Williams & Wilkins, 2003:227.
2. Shyu KG, Tseng CD, Chiu IS, et al. Infundibular pulmonic
stenosis with intact ventricular septum: a report of 15 surgically
corrected patients. Int Cardiol 1993;41:115–21.
3. Angelkov L Trajic S, Popovic Z, et al. Acute effects of DDD
pacing in patients with pulmonary infundibular stenosis. Am J
Cardiol 1999;84:117–18.
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