Imaging of vascular remodeling after simulated thoracoabdominal aneurysm repair

ObjectiveA better understanding of the response of the spinal cord blood supply to segmental artery (SA) sacrifice should help minimize the risk of paraplegia after both open and endovascular repair of thoracoabdominal aortic (TAA) aneurysms.MethodsTwelve female juvenile Yorkshire pigs were randomized into 3 groups and perfused with a barium–latex solution. Pigs in group 1 (control) had infusion without previous intervention. Pigs in group 2 were infused 48 hours after ligation of all SAs (T4-L5) and those in group 3 at 120 hours after ligation. Postmortem computed tomographic scanning of the entire pig enabled overall comparisons and measurement of vessel diameters in the spinal cord circulation.ResultsWe ligated 14.5 ± 0.8 SAs: all filled retrograde to the ligature. Paraplegia occurred in 38% of operated pigs. A significant increase in the mean diameter of the anterior spinal artery (ASA) was evident after SA sacrifice (P < .0001 for 48 hours and 120 hours). The internal thoracic and intercostal arteries also increased in diameter. Quantitative assessment showed an increase in vessel density 48 hours after ligation of SAs, reflected by an obvious increase in small collateral vessels seen on 3-dimensional reconstructions of computed tomographic scans at 120 hours.ConclusionsRemodeling of the spinal cord blood supply—including dilatation of the ASA and proliferation of small collateral vessels—is evident at 48 and 120 hours after extensive SA sacrifice. It is likely that exploitation of this process will prove valuable in the quest to eliminate paraplegia after TAA aneurysm repair

Reoperative aortic root and transverse arch procedures: A comparison with contemporaneous primary operations

ObjectivesLong-term survival and risk factors affecting outcome after reoperative root/ascending aorta and transverse arch procedures have not been clearly described.MethodsTwo hundred patients (138 male patients; age, 60 ± 15 years) underwent reoperative root/ascending aorta (n = 100) or transverse arch (n = 100) procedures at our institution from January 1998 to December 2004 and were compared with 480 consecutive contemporaneous patients with primary procedures (323 male patients; age, 62 ± 16 years; 335 proximal aorta and 145 transverse arch procedures).ResultsReoperative proximal aorta procedures had a higher hospital mortality (7%) than primary root/ascending aorta procedures (3%), but there was a less dramatic difference in operative mortality after primary and reoperative arch procedures (9% vs 10%). Separate multivariable analyses of root/ascending aorta procedures and arch procedures revealed chronic obstructive pulmonary disease and age to be significant risk factors for death after either procedure. In addition, an ejection fraction of less than 30% posed a significant risk for proximal aortic surgery, and diabetes and nonelective operations predicted poorer outcome after arch operations. For survivors of root/ascending aorta operations, there was no significant difference in long-term outcome between reoperations and primary procedures, with both restoring longevity to expected levels for an age- and sex-matched normal population. Patients undergoing arch operations, however, continued to have a poorer long-term outlook than their normal peers.ConclusionsIn this series, reoperations in the transverse arch carry the same risk as primary arch procedures, but a higher operative mortality is seen with reoperative than with primary root/ascending aorta procedures. The long-term outlook is better for patients undergoing root/ascending operations than for patients undergoing aortic arch operations, with no difference in the longevity of patients undergoing primary procedures versus reoperations

Simultaneous antegrade/retrograde normothermic perfusion with blood (beating heart) for aortic root replacement in acute type-a dissection of the aorta

A new technique of myocardial protection was utilized in performing surgery for acute type-A dissection involving the aortic valve, requiring replacement of the root. Simultaneous antegrade and retrograde perfusion of the heart with normothermic blood at high flows allows for safe and precise surgery, without concerns for the period of aortic clamping, since ischemia is eliminated altogether

Concomitant Beating-Heart Mitral Valve Surgery and Coronary Artery Bypass in Patients with Compromised Ventricular Function

Background Surgical repair of mitral valve disease and concomitant coronary artery occlusive disease has high operative risk. Myocardial protection for protracted, complicated procedures is seminal to the overall operative outcome; specifically, preservation of left ventricular function. Methods The authors conducted a retrospective review of 25 patients undergoing combined mitral valve repair/replacement (MVR) and coronary artery bypass surgery (CABG) using the beating-heart technique at the Miller/University of Miami School of Medicine. The CABG was performed without cardiopulmonary bypass support. During the mitral valve surgery the perfusion pressure was maintained at 80–90 mm Hg and the systemic temperature at 35–36°C. The aorta was not cross-clamped. Results Twenty-five patients underwent MVR/CABG, including 7 patients with acute myocardial infarction. Preoperative echocardiograms revealed a mean ejection fraction (EF) of 41 ± 4.5%. One patient required a preoperative intraarterial balloon pump. An average of 2.12 ± 0.9 grafts and a total of 10 mitral valve repairs were performed. The average length of stay in the intensive care unit was 14 ± 1.8 days, and average hospitalization time was 23 ± 3. The mean postoperative EF was 41 ± 4.5%. The mortality in this patient group was 12 % (3/25) with a morbidity rate of 52% (13/25). Conclusions The data suggest that the technique is safe and reproducible, and that it potentially has a short-term benefit on left ventricular function. Therefore, this particular technique may be efficacious in patients with compromised left ventricular function requiring a combined MVR/CABG

Harmonic scalpel for pericardiectomy: novel approach to an old cardiac dilemma

Pericardiectomy for constrictive or calcific pericarditis is a technical challenge because of dense adhesions to the epicardial surface of the heart. The procedure is fraught with the possibility of urgent cardiopulmonary bypass from excessive bleeding or cardiac laceration. We propose the use of a harmonic scalpel to perform adhesiolysis with less bleeding and cardiac trauma. A retrospective review of 7 pericardiectomies performed with a handheld harmonic scalpel over the past 2 years was performed. Requirements for blood products, the need for cardiopulmonary bypass, and mortality were examined. Four of the patients underwent pericardiectomy alone, and 3 patients underwent pericardiectomy with additional cardiac procedures. The 30-day mortality was zero. No patient needed blood transfusions or urgent cardiopulmonary bypass for bleeding. No patient developed malignant arrhythmias. Use of a harmonic scalpel is a safe and efficient technique for pericardiectomy. Adhesiolysis is less treacherous because of the bloodless operative field; moreover, the harmonic scalpel is not arrhythmogenic

Congenital Absence of the Right Upper Lobe Bronchus With Double Segmental Tracheal Bronchi

A multidisciplinary approach revealed an absent right upper lobe bronchus and atretic bronchioles in a child with recurrent pulmonary infections. Use of a multidimensional computed tomographic scan and bronchoscopy clearly delineated the anatomical aberration. The child underwent an uncomplicated right upper anterior segmentectomy with an expedient recovery

A prospective study of growth and rupture risk of small-to-moderate size ascending aortic aneurysms

ObjectiveThe natural history of small-to-moderate size ascending aortic aneurysms is poorly understood. To follow these patients better, we have developed a method to objectively and reproducibly measure ascending aortic volume on the basis of gated contrast computed tomography scans.MethodsFrom 2009 to 2011, 507 patients were referred for management of ascending aortic aneurysms. A total of 232 patients (46%) with small-to-moderate size aneurysms who did not have compelling indications for operation had measurement(s) of ascending aortic and total aortic volume; 166 patients had more than 1 scan, allowing measurement of growth. A total of 66 patients admitted to the emergency department without ascending aortic pathology served as a reference group.ResultsNone of the patients experienced rupture, dissection, or death; 3 patients ultimately underwent operation. Ascending aortic volume and volume/total aortic volume differed for the surveillance and reference groups: 132.8 ± 39.4 mL versus 78.0 ± 24.5 mL; 38.3% ± 7.4% versus 29.1% ± 3.9%, respectively (both P < .001). Diameters at the sinotubular junction and mid-ascending aortic were 4.1 ± 0.6 cm and 4.4 ± 0.6 cm, respectively, for the surveillance group and 3.0 ± 0.4 cm and 3.2 ± 0.4 cm, respectively, for controls. The increase in ascending aortic volume was 0.95 ± 4.5 mL/year and 0.73% ± 3.7%/year (P = .007 and .012, respectively). Analysis of risk factors for ascending aortic growth revealed only the use of antithrombotic medication as possibly significant.ConclusionsComputed tomography volume measurements provide an objective method for ascertaining aortic size and monitoring expansion. Patients with small-to-moderate ascending aortic aneurysms who are carefully followed and managed appropriately have slow aneurysm growth and a small risk of rupture or dissection. Annual computed tomography screening may not be indicated, and elective resection—absent other surgical indications—is not necessary. The rupture/dissection risk for even larger aneurysms in carefully followed patients may be lower than currently believed