Ghannam A. Al-Dossari

Valve repair versus valve replacement for degenerative mitral valve disease.

OBJECTIVE The study objective was to identify characteristics differentiating patients undergoing valve replacement versus valve repair for degenerative mitral valve disease and to use this information to compare survival and reoperation after each procedure. METHODS From 1985 to 2005, 3286 patients underwent isolated primary operation for degenerative mitral valve disease. Valve repair was performed in 3051 patients (93%), and valve replacement was performed in 235 patients (7.2%). A propensity model and score developed for fair comparison of outcomes yielded 195 matched pairs. RESULTS Patients undergoing replacement were older (70 +/- 12 years vs 57 +/- 13 years) and had more complex valvar pathology, symptoms, and left ventricular dysfunction. Thus, the characteristics of the propensity-matched patients undergoing repair more resembled those of the patients undergoing replacement (older, complex valvar pathology) than patients undergoing typical repair. Eight patients died in the hospital (0.26%) after repair and 5 patients (2.1%) died after replacement (P = .001). Unadjusted survival at 5, 10, and 15 years was 95%, 87%, and 68% after repair and 80%, 60%, and 44% after replacement, respectively (P < .0001); however, among propensity-matched patients, survival was similar (P = .8): 86% versus 83% at 5 years, 63% versus 62% at 10 years, and 43% versus 48% at 15 years. Freedom from reoperation among propensity-matched patients was 94% at 5 and 10 years after repair and 95% and 92% at 5 and 10 years after replacement, respectively (P = .6). CONCLUSION It is reasonable to perform valve repair in elderly patients with complex degenerative mitral valve pathology because it can eliminate the need for anticoagulation and risk of prosthesis-related complications. However, when valve pathology is so complex that repair is infeasible, this study demonstrates that valve replacement does not diminish long-term outcomes.

Experimental large-animal model of obliterative bronchiolitis after lung transplantation

Obliterative bronchiolitis is a major cause of long-term morbidity after lung transplantation. It is characterized by small-airway inflammation and occlusion by fibrous tissue. The pathogenesis is uncertain. To study this disease, we developed a model of posttransplantation obliterative bronchiolitis using genetically defined miniature swine. Group 1 (n = 2) received a left lung autograft; group 2 (n = 7), a left lung allograft. Group 2 recipients were given cyclosporine, prednisone, and azathioprine for 3 months, then immunosuppression was tapered and discontinued over 1 month. The animals were observed for an additional 2 months, then sacrificed. Lung grafts in both groups were monitored with serial bronchoalveolar lavages and transbronchial biopsies for 6 months. After sacrifice, lung grafts underwent histopathologic and immunohistochemical examination. No allograft had histologic evidence of acute rejection or peribronchiolar infiltrate during the first 3 months of immunosuppression. During the tapering period, airway changes characterized by severe peribronchiolar lymphocytic infiltrates were seen. Bronchoalveolar lavages of allografts showed significantly increased lymphocyte counts with CD8+ cells predominating. After the discontinuation of immunosuppression, transbronchial biopsy and autopsy specimens showed progressive fibrous inflammatory occlusion of bronchioles. Immunohistochemical staining demonstrated increased expression of MCH class II antigen on the bronchiolar epithelium and increased dendritic cells and CD4+ lymphocytes. None of these changes were seen in group 1. Our findings suggest obliterative bronchiolitis is an immunologically mediated phenomenon related to chronic graft rejection after lung transplantation. This model will allow systematic study of the pathogenesis of obliterative bronchiolitis and possible therapeutic intervention.

Occult Internal Mammary Artery Neurofibromatosis: A Case for Caution in Coronary Revascularization

Intrathoracic neurofibromas are relatively uncommon in patients with neurofibromatosis. They are usually asymptomatic and may be discovered incidentally. We present the case of a 51-year-old, African American man with neurofibromatosis type 1 who underwent coronary revascularization. Intraoperatively, numerous neurofibromas were discovered, one of which was attached to the left internal mammary artery. The procedure was uncomplicated despite the challenging intraoperative findings. Special considerations in the management of patients with neurofibromatosis undergoing cardiac surgery are discussed, including risks, preoperative imaging and the importance of excision of suspicious tumors.

Management of ventricular perforation during revascularization of an intramyocardial left anterior descending artery

Ventricular perforation during exposure of an intramyocardial left anterior descending artery (LAD) in preparation for coronary artery bypass grafting is a known surgical complication. In this report, we discuss the management of this complication which avoids closure of the LAD and a myocardial infarction.

Diarrhea—An uncommon presentation of tertiary adrenal insufficiency following heart transplantation

Diarrhea following organ transplantation is usually associated with infection and immunosuppression therapy. We describe two patients with diarrhea following orthotopic heart transplantation due to tertiary adrenal insufficiency.

Utility of real-time three-dimensional echocardiography in improved assessment of a mitral valve papillary fibroelastoma

Primary cardiac tumors are exceedingly rare. They are usually first identified by transthoracic echocardiography. However, transesophageal echocardiography (TEE), with the aid of real‐time three‐dimensional (3D) imaging, can provide additional important mass characteristics. We present a case that demonstrates the usefulness of 3D TEE in characterizing a papillary fibroelastoma.

Abundant dystrophic calcifications mimicking aortic valve abscess in a patient undergoing elective aortic valve replacement

Dystrophic calcifications of the aortic valve may cause symptomatic aortic stenosis and account for a significant portion of patients who undergo elective valve replacement. Calcifications appearing grossly as a cloudy fluid surrounding the aortic valve leaflets are an uncommon finding. Normally, calcified aortic valves are characterised by large, nodular masses within the aortic cusps. We report a case of dystrophic calcifications on a stenotic aortic valve encountered intraoperatively, which was suggestive of infective endocarditis and abscess formation. Aortic valve leaflets and necrotic-appearing thymic lymph node tissue were submitted for histology and special stains. Cultures were negative and histology did not show evidence of infection. Tissue histology demonstrated extensive dystrophic calcifications, which were polarised to reveal abundant calcium oxalate crystals. The benign nature of this unique pathological finding ruled out any suspicion of infection, avoiding a prolonged course of intravenous antibiotics in this patient.

The Anomalous Coronary Artery in Aortic Valve Replacement: A Case For Caution

We report obstruction of an anomalous right coronary artery traversing between the pulmonary artery and aorta after placement of a 21-mm bovine bioprosthesis for critical aortic stenosis requiring emergency revascularization. Although this anomaly has been associated with sudden death syndrome, acute coronary ischemia resulting from aortic valve replacement in patients with anomalous coronary artery has not been sufficiently highlighted in the literature. Awareness of this issue may decrease the risk of this complication in patients with anomalous coronary anatomy undergoing aortic or pulmonary valve replacement. Furthermore, the need for careful preoperative imaging in patients undergoing semilunar valve replacement is essential.