Article

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

Division of Cardiology, Department of Pediatrics, The Children's Hospital of Philadelphia, and the University of Pennsylvania School of Medicine, 34th Street and Civic Center Blvd., Philadelphia, PA 19104, USA.
American Heart Journal (Impact Factor: 4.46). 05/2001; 141(4):630-6. DOI: 10.1067/mhj.2001.113576
Source: PubMed

ABSTRACT

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 conduits 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 imaging (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 MRI scans.
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 operation, 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 obstruction. MRI is a useful tool to complement anatomic diagnosis by echocardiography. Conduit obstruction is common, and late mortality rates appear to be high.

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    • "Further, the AAC insertion operation, with or without CPB, is not as technically straightforward as direct aortic valve replacement. Nonetheless, several series have demonstrated that AAC insertion successfully lessens the LVaortic pressure gradient, preserves or improves ventricular function and maintains normally distributed blood flow through the systemic and coronary circulation [10] [11] [12]. While there have been several techniques described, the most commonly employed method is the lateral thoracotomy approach with placement of the AAC to the descending aorta. "
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    ABSTRACT: Recently, we implanted an apicoaortic conduit off-pump in three high-risk patients with severe aortic stenosis. A muscle-coring device was utilized to create the apical outflow tract followed by insertion of a rigid apical connector. A valved conduit was then connected to the descending thoracic aorta and to the apical connector graft. A stentless porcine bioprosthesis was implanted in two patients and a stented valve in one. The left ventricular (LV)-aortic gradients were reduced from a mean of 66 to 28 mmHg. With modification of an existing technique, apicoaortic conduit insertion can be performed safely off-pump. This technique can be applied to complex forms of LV outflow obstruction and high-risk patients.
    Preview · Article · Mar 2003 · European Journal of Cardio-Thoracic Surgery
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    • "Further, the AAC insertion operation, with or without CPB, is not as technically straightforward as direct aortic valve replacement. Nonetheless, several series have demonstrated that AAC insertion successfully lessens the LVaortic pressure gradient, preserves or improves ventricular function and maintains normally distributed blood flow through the systemic and coronary circulation [10] [11] [12]. While there have been several techniques described, the most commonly employed method is the lateral thoracotomy approach with placement of the AAC to the descending aorta. "
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    ABSTRACT: Objectives: Recently, we implanted an apicoaortic conduit off-pump in three high-risk patients with severe aortic stenosis. Methods :A muscle-coring device was utilized to create the apical outflow tract followed by insertion of a rigid apical connector. A valved conduit was then connected to the descending thoracic aorta and to the apical connector graft. Results: A stentless porcine bioprosthesis was implanted in two patients and a stented valve in one. The left ventricular (LV)-aortic gradients were reduced from a mean of 66 to 28 mmHg. Conclusions: With modification of an existing technique, apicoaortic conduit insertion can be performed safely off-pump. This technique can be applied to complex forms of LV outflow obstruction and high-risk patients. q 2002 Elsevier Science B.V. All rights reserved.
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    No preview · Article · Feb 2002 · Methods in Enzymology
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