Ichiro Yoshioka

Tagged cine magnetic resonance imaging with a finite element model can predict the severity of retrosternal adhesions prior to redo cardiac surgery

OBJECTIVE Reoperative median sternotomy entails a risk of damaging the heart or great vessels. If the severity of retrosternal adhesion is accurately assessed before sternal re-entry, resternotomy-related complications can be prevented. The purpose of this investigation was to evaluate whether the severity of retrosternal adhesions can be accurately predicted by tagged cine magnetic resonance imaging. METHODS Thirteen patients who were scheduled to undergo cardiac reoperation were investigated by electrocardiography-gated tagged cine magnetic resonance imaging before sternal re-entry. With the imaging data, the severity of retrosternal adhesion was scored visually on the basis of abnormality in regional myocardial motion and discordance in the tagged signals of the sternum and the myocardium. Also, with the aid of a finite element model, strain at the surface of the right ventricle was calculated on the basis of displacement of the tags on the heart over the cardiac cycle. For comparison, the adhesion severity was scored visually at the time of redo surgery by surgeons who were blinded to the preoperative assessment. RESULTS The preoperative adhesion severity score, as determined visually by tagged cine magnetic resonance imaging, was correlated with the intraoperative severity score (correlation coefficient: r = 0.76, P < .01). Mean strain at the surface of the heart, as calculated preoperatively by finite element model analysis, was inversely correlated with the intraoperative adhesion severity score (r = -0.78, P < .01). CONCLUSION Tagged cine magnetic resonance imaging with a finite element model can provide an accurate quantitative assessment of retrosternal adhesions before redo cardiac surgery.

Modification of a Standard Thoracoabdominal Incision to Preserve Collaterals to Adamkiewicz Artery

We report a case of a 35-year-old male who underwent thoracoabdominal aortic repair of a chronic dissecting aortic aneurysm, Crawford extent II. Preoperative computed tomography showed thrombosis of almost all intercostal arteries. Precise diagnostic assessment demonstrated the Adamkiewicz artery originating from the left lateral thoracic artery and subscapular artery, which would have been at risk after using a standard Stoneys incision, thus potentially causing paraplegia or paraparesis due to spinal cord ischemia. We modified the lateral thoracic incision anteriorly and successfully preserved the collateral arteries without impairing the spinal cord function.

Modifying Anastomotic Site in Thoracic Aortic Surgery by Using Biodegradable Felt Strips With or Without Basic Fibroblast Growth Factor

Results: The medial thickness in the PTFE group was significantly lower than that of the PGA with bFGF group (66±5% versus 90±4% of control, < 0.05). The adventitial layer in the PTFE group significantly decreased in thickness compared to control (42±8% of control, < 0.05), whereas those in the PGA and PGA with bFGF groups significantly thickened (117±11 and 134±14% of control, respectively, < 0.05), which was associated with increased vessel number. The failure force measured at anastomotic sites did not show statistical difference between the four groups.

A Counterpulsation Technique for Use During Complicated Aortic Surgery With Residual Thoracoabdominal Aortic Aneurysm

Mechanical circulatory support can be difficult for patients with thoracoabdominal aortic disease. We herein describe a counterpulsation technique using an intra-graft balloon pump that can be safely used in the setting of thoracoabdominal aortic aneurysm remaining immediately after aortic root and arch replacement coupled with coronary artery bypass grafting.