have all been reported.
There has even been a report of a patient with an AAC
All these events present a formida-
ble task for evaluation and treatment.
The combination of Doppler echocardiography and
magnetic resonance imaging (MRI) has played a major
role in the evaluation and treatment of many of these
patients at our institution. Because the AAC runs along
the base of the left lung, it is difficult to visualize this
structure by 2-dimensional (2D) echocardiography. Fur-
thermore, the angles of interrogation that can be
obtained make Doppler evaluation problematic. Hence
2D and 3-dimensional (3D) MRI has been used to evalu-
ate overall anatomy and to examine the AAC for areas of
obstruction, valvular dysfunction, thrombi, or vegeta-
tion. It has been useful before surgery in the subsequent
evaluation after the operating theater.
This study reports our institutional experience in the
follow-up of patients with AAC over an average period
of 6 years with the use of these imaging modalities. In
addition, we tested the hypothesis that Doppler interro-
gation of the native LVOT can be useful in determining
Interposition of an extracardiac conduit between the
left ventricular (LV) apex and the descending aorta
(DAo) has been used in children and adults since
This apico-aortic conduit (AAC) operation for
LV outflow tract (LVOT) obstruction has been used in
many varied diseases such as hypertrophic cardiomy-
and congenital aortic
Although other operations such as the Ross-
Konno have generally supplanted the use of AAC, the
latter remains a useful option in infants with LVOT
obstruction, and survivors of AAC still continue to pre-
sent a challenge at follow-up.
Complications such as
AAC valve dysfunction,
Division of Cardiology, Department of Pediatrics, and the
Radiology, The Children’s Hospital of Philadelphia, and the University of Pennsylva-
nia School of Medicine, Philadelphia.
Submitted August 14, 2000; accepted December 12, 2000.
Reprint requests: Mark A. Fogel, MD, Children’s Hospital of Philadelphia, Division
of Cardiology, 34th St and Civic Center Blvd, Philadelphia, PA 19104.
Copyright © 2001 by Mosby, Inc.
0002-8703/2001/$35.00 + 0 4/1/113576
Evaluation and follow-up of patients with left
ventricular apical to aortic conduits with 2D and 3D
magnetic resonance imaging and Doppler
echocardiography: A new look at an old operation
Mark A. Fogel, MD,
Jack Rychik, MD,
Alvin J. Chin, MD,
Anne Hubbard, MD,
and Paul M Weinberg, MD
Although the interposition of left ventricular apical to descending aorta conduits has diminished with the
advent of the Ross-Konno operation, it remains a useful option. We reviewed our institutional experience imaging these con-
duits and tested the hypothesis that the gradient across the native left ventricular outflow tract (LVOT) by echocardiography
correlated with the conduit gradient by cardiac catheterization. In a patient with an unobstructed conduit, no gradient
should exist across the native LVOT.
This was a retrospective review of the echocardiography, cardiac catheterization, magnetic resonance imag-
ing (MRI) data, and history of 9 patients with these conduits over an 8-year period. In 7 of 9 patients, 8 conduit obstruction
events were assessed by Doppler interrogation of the native LVOT and by cardiac catheterization. Five patients underwent 6
In all cases of obstruction diagnosed by catheterization (56.3 ± 21.9 mm Hg), Doppler echocardiography
demonstrated gradients across the native LVOT (69.3 ± 21.2 mm Hg, r = 0.67). Because 2D echocardiography could not
visualize the entire conduit in any patient, 2- and 3-dimensional MRI was used successfully to evaluate anatomy and identify
the site of obstruction. All patients manifested conduit obstruction. Four (44%) of 9 patients died, 3 underwent the Ross oper-
ation, 1 continues to live with his original conduit, and 1 was lost to follow-up.
A gradient by Doppler interrogation of the native LVOT is an indirect means of assessing conduit obstruc-
tion. MRI is a useful tool to complement anatomic diagnosis by echocardiography. Conduit obstruction is common, and late
mortality rates appear to be high. (Am Heart J 2001;141:630-6.)