This case presents a patient who underwent aortic valve replacement and presented 13 years later with high gradients across the prosthesis, mitral insufficiency, and severe systemic hypertension. Her preoperative workup led to the diagnosis of an interrupted aortic arch Type A. Her surgical management included an initial procedure to repair the interruption, and 11 months later after resolution of her hypertension, a second surgery, which included the Ross procedure and mitral valve repair.
by
David H. Tian;
Benjamin Wan;
Paul G. Bannon;
Martin Misfeld;
Scott A. Lemaire;
Teruhisa Kazui;
Nicholas T. Kouchoukos;
John A. Elefteriades;
Joseph E. Bavaria;
Joseph S. Coselli;
Randall B. Griepp;
Friedrich W. Mohr;
Aung Oo;
Lars G. Svensson;
G. Chad Hughes;
Malcolm J. Underwood;
Edward Chen;
Thoralf M. Sundt;
Tristan D. Yan
Introduction
Recognizing the importance of neuroprotection in aortic arch surgery, deep hypothermic circulatory arrest (DHCA) now underpins operative practice as it minimizes cerebral metabolic activity. When prolonged periods of circulatory arrest are required, selective antegrade cerebral perfusion (SACP) is supplemented as an adjunct. However, concerns exist over the risks of SACP in introducing embolism and hypo- and hyper-perfusing the brain. The present meta-analysis aims to compare postoperative outcomes in arch surgery using DHCA alone or DHCA + SACP as neuroprotection strategies.
Methods
Electronic searches were performed using six databases from their inception to January 2013. Two reviewers independently identified all relevant studies comparing DHCA alone with DHCA + SACP. Data were extracted and meta-analyzed according to pre-defined clinical endpoints.
Results
Nine comparative studies were identified in the present meta-analysis, with 648 patients employing DHCA alone and 370 utilizing DHCA + SACP. No significant differences in temporary or permanent neurological outcomes were identified. DHCA + SACP was associated with significantly better survival outcomes (P=0.008, I2=0%), despite longer cardiopulmonary bypass time. Infrequent and inconsistent reporting of other clinical results precluded analysis of systemic outcomes.
Conclusions
The present meta-analysis indicate the superiority of DHCA + SACP in terms of mortality outcomes.
Accurate identification of in vivo nonlinear, anisotropic mechanical properties of the aortic wall of individual patients remains to be one of the critical challenges in the field of cardiovascular biomechanics. Since only the physiologically loaded states of the aorta are given from in vivo clinical images, inverse approaches, which take into account of the unloaded configuration, are needed for in vivo material parameter identification. Existing inverse methods are computationally expensive, which take days to weeks to complete for a single patient, inhibiting fast feedback for clinicians. Moreover, the current inverse methods have only been evaluated using synthetic data. In this study, we improved our recently developed multi-resolution direct search (MRDS) approach and the computation time cost was reduced to 1~2 hours. Using the improved MRDS approach, we estimated in vivo aortic tissue elastic properties of two ascending thoracic aortic aneurysm (ATAA) patients from pre-operative gated CT scans. For comparison, corresponding surgically-resected aortic wall tissue samples were obtained and subjected to planar biaxial tests. Relatively close matches were achieved for the in vivo-identified and ex vivo-fitted stress-stretch responses. It is hoped that further development of this inverse approach can enable an accurate identification of the in vivo material parameters from in vivo image data.