Bashar Abul Hasan Muhammad

Total arch replacement using aortic arch branched grafts with the aid of antegrade selective cerebral perfusion

BACKGROUND We report our clinical experience with total arch replacement using aortic arch branched graft in an attempt to determine the independent predictors of both in-hospital mortality and neurologic outcome. METHODS We studied 220 consecutive patients who underwent total arch replacement using aortic arch branched graft between May 1990 and June 1999. All operations were performed with the aid of hypothermic extracorporeal circulation, antegrade selective cerebral perfusion, and open distal anastomosis. RESULTS The overall in-hospital mortality rate was 12.7%. Multivariable analysis showed independent determinants of in-hospital mortality to be chronic renal failure, long pump time, participation in early series, and shock. Postoperative permanent neurologic dysfunction was 3.3%. On multivariable analysis, old cerebral infarct and pump time were independent determinants of permanent neurologic dysfunction. The selective cerebral perfusion time had no significant influence on in-hospital mortality or neurologic outcome. The 5-year survival rate including in-hospital deaths was 79% +/- 6%. CONCLUSIONS Selective cerebral perfusion allows increased ease of performance of total arch replacement, a complex and time-consuming procedure, and helps reduce periprocedural mortality and morbidity in patients with aortic arch aneurysm and those with acute aortic dissection.

Extended total arch replacement for acute type a aortic dissection: Experience with seventy patients

OBJECTIVE We sought to report the clinical experience with extended total arch replacement for acute type A aortic dissection and to determine the factors that influence early mortality, late survival, and late reoperation. METHODS Between December 1988 and August 1998, 70 patients underwent emergency graft replacement of both the ascending aorta and the total aortic arch for acute type A aortic dissection. All operations were performed with hypothermic extracorporeal circulation, selective cerebral perfusion for cerebral protection during aortic arch repair, and open distal anastomosis. Concomitant procedures included aortic valve resuspension in 18 patients, composite graft replacement in 10 patients, and coronary artery bypass grafting in 5 patients. RESULTS The early mortality rate was 16% (11 of 70 patients). Multivariable analysis showed that renal-mesenteric ischemia and coronary artery bypass grafting were independent determinants for early death. Survival rates at 3 and 5 years postoperatively, including the early deaths, were 75% +/- 5% and 73% +/- 6%, respectively. Multivariable analysis showed that renal-mesenteric ischemia and en bloc repair were independent determinants for late death. Freedom from reoperation was 91% +/- 4% and 77% +/- 8% at 3 and 5 years, respectively. Multivariable analysis showed that anastomotic leakage was the only significant determinant for late reoperation. CONCLUSIONS Extended total arch replacement for acute type A aortic dissection could be justified in properly selected patients.

PHARMACOKINETIC ADVANTAGES OF A NEWLY DEVELOPED TACROLIMUS OIL-IN-WATER-TYPE EMULSION VIA THE ENTERAL ROUTE

We developed an oleic acid oil-in-water (o/w)-type emulsion of a new tacrolimus formulation that presented an improvement in the delivery of the drug for oral absorption. This investigation was undertaken to assess a sustained release drug delivery system and selective drug transfer into the lymphatic system. The whole blood concentration profiles after oral administration at a dose of 2mg/kg and bone marrow, spleen, liver, lung, small intestine, kidney, brain, and whole blood distribution after oral administration at a dose of 1 mg/kg of o/w emulsion formulation of tacrolimus (O/W group) were compared with those of commercially available formulation (T group) in the rat. The mean diameter of the o/w emulsion droplets was 0.47 μm immediately after preparation. The tacrolimus entrapping efficiency of o/w emulsion was 71.3+5.0% in 12 h and did not change for 2 d. The area under the whole blood concentration-time curve (AUC) in the O/W group was significantly higher (P<0.01) than that in the I group. In contrast, the values of constant elimination rate and total clearance in the O/W group were significantly lower (P<0.01) than those in the T group, with a comparative bioavailability of 115.9%. The tissue concentration of tacrolimus in the O/W group was significantly higher levels in the bone marrow, spleen, liver, lung, and small intestine, and significantly lower in the brain and kidney, relative to the T group. The o/w emulsion of tacrolimus may be an improved dosage form via the enteral route.

Laparoscopic surgery for gonadal dysgenesis in children.

Three pediatric phenotypic females presented with gonadal dysgenesis. Their gonads were removed laparoscopically. These phenotypically normal females, who do not have any intersex problems or ambiguous genitalia, represent a unique group of patients having a Y chromosome or a fragment of it in their genetic constitutions. We performed laparoscopic adnexectomy with Endoloop ligatures or an ultrasonically activated scalpel. No significant complication occurred in any of the cases. Pathologic examination revealed gonadoblastoma in one of the gonads of one patient. We propose that laparoscopic surgery is a safe and minimally invasive procedure for prophylactic gonadectomy to prevent neoplasia, even when performed on pediatric patients.

Aortic regurgitation with dilation of ascending aorta and right coronary artery occlusion by a rudimentary aortic cusp

Occlusion of a coronary artery ostium, especially that of the right by an aortic cusp, is a rare congenital anomaly. We had the experience of dealing with an adult patient with aortic regurgitation due to a rudimentary aortic cusp that also occluded the right coronary ostium. We performed composite graft replacement because the patient also had coexistent dilation of the ascending aorta. Postoperative course was uneventful.

Repair of Delayed Left Ventricular Rupture After Mitral Valve Replacement : Report of a Case

Rupture of the left ventricle (LV) after mitral valve replacement (MVR) is a devastating complication, associated with high mortality. A 64-year-old woman with a type I delayed LV rupture, which occurred after MVR with a 27-mm St. Jude Medical mitral prosthesis for mitral stenosis, was successfully treated by a combination of intracardiac and extracardiac surgical repair techniques. The extracardiac repair involved approximating the edges of myocardium around the tear with large sutures bolstered by strips of Teflon felt, then covering the epicardial hematoma with another porcine pericardial patch, using gelatin resorcinol formaldehyde glue and collagen sheets. The intracardiac repair involved suturing the edges of an oval piece of porcine pericardium to the endocardium around the laceration. No LV pseudoaneurysm was detected postoperatively on echocardiography or computed tomography scans. The patient is well 2 years after the operation.

Surgical treatment of annuloaortic ectasia with coronary aneurysm and fistula

Annuloaortic ectasia associated with a giant aneurysm of the left coronary artery and a coronary artery fistula is extremely rare, and it is difficult to decide how to repair this complex lesion. The cause of the huge aneurysm of the left coronary artery in our patient was thought to be cystic medial necrosis, the coronary artery fistula, or both. The surgical management of this extremely rare pathological combination is described.