Alexander Evans

Mechanisms and future directions for prevention of vein graft failure in coronary bypass surgery

Coronary artery bypass grafting has been utilized as a beneficial treatment for myocardial ischemic disease for over three decades. Failure of coronary artery venous grafts occurs at a substantial rate and has a large impact on two main endpoints, survival and quality of life. An exhaustive amount of basic research has been generated to delineate possible mechanisms responsible for graft failure and modalities to prevent its occurrence. Although pharmacotherapy exists, insufficient translation has emerged from the bench to the operating room. In this article, we review the literature regarding the current mechanisms and mediators including growth factors, nitric oxide and genetics leading to saphenous vein graft occlusion. The review addresses the current state of affairs and modes for prevention of vein graft failure perioperatively and newer technologies that may help ameliorate this problem in the future.

Primary neuroendocrine tumors of the thymus

Primary neuroendocrine tumors of the thymus are highly aggressive tumors that rarely occur. A little more than 200 cases have been reported, many of which were single case reports. Only a few articles contained modest series from single centers for analysis. A review of 157 cases collected from the major series reported to-date show a clinical pattern with male preponderance (male:female ratio, 3:1) and a mean age of 54 years. Most patients presented with symptoms and signs of local compression. Almost 50% of these tumors were functionally active and were associated with endocrinopathies. Several histologic variants have been described, all with similar ultrastructural features. The biologic behavior of these tumors shows a direct relation to the degree of differentiation. Whenever possible, surgical resection is the treatment of choice as adjuvant therapy is controversial and has been used with variable success. Potential therapies exploit the presence of somatostatin receptors on a variety of these tumors. Use of radiolabeled Octreotide for radionuclide therapy has yielded tumor inhibition in animal models and may have clinical application. Fifty-one percent of the patients survived 3 years, 27% survived 5 years, and less than 10% survived beyond 10 years. Histologic grade, tumor extension, and early detection are the most important factors affecting survival. Other prognostic factors that impact outcome include presence of endocrinopathy, incomplete resectability, nodal status, and presence of distant metastasis.

Outcomes of Coronary Artery Bypass Grafting versus Percutaneous Coronary Intervention and Medical Therapy for Multivessel Disease with and without Left Ventricular Dysfunction

Multiple randomized trials support the treatment of patients with multivessel coronary artery disease (CAD) and relatively normal left ventricular (LV) ejection fraction (EF) by either percutaneous coronary intervention (PCI) or coronary artery bypass grafting (CABG). However, there has been a paucity of trials in the recent literature that have compared the outcomes of patients with multivessel CAD and low EF who undergo PCI or CABG. This review examines some of the clinical trials and series in this subgroup of patients and also compares the outcome of patients undergoing either procedure in the absence and presence of LV dysfunction. These trials and series support the notion that PCI can be successfully performed in patients with low EF with relatively low mortality, but that CABG is associated with greater freedom from repeat revascularization and from angina or congestive heart failure symptoms. In addition, most of the data published thus far indicate a long-term survival advantage among patients with ventricular dysfunction who have undergone CABG. Further studies, including randomized trials incorporating the evolving techniques of CABG and the recent advances in PCI, will be needed to assess the proper role and outcome of these two interventions.

Acute postoperative shingles after thoracic sympathectomy for hyperhidrosis.

Shingles secondary to reactivation of a previous varicella-zoster virus infection has been reported to develop within surgical wounds and after trauma. We report the case of a 17-year-old girl with history of chicken pox in childhood who had acute postoperative shingles develop along the T3-T4 dermatomes after thoracic sympathectomy for hyperhidrosis. The possible causes and precipitating factors are discussed.

Late presentation of retained intracardiac ice pick with papillary muscle injury

An unusual case of a penetrating intracardiac injury is described in a 16-year-old boy who presented with a retained 14-cm segment of an ice pick that went unnoticed by the patient for 4 days. The ice pick had lacerated the anterior papillary muscle of the left ventricle causing avulsion of its tip and prolapse of the anterior leaflet of the mitral valve resulting in severe mitral regurgitation. The urgency for surgical correction of the traumatic mitral valve injury at the time of extraction of the intracardiac foreign body through a single-stage approach versus a two-stage approach is discussed.