Surgical approach to ascending aorta in bicuspid aortic valve

OBJECTIVE: Former studies have pointed out that hemodynamic stress imposed by associated valvular disease is the primary factor in the development of ascending aorta dilatation. At present, intrinsic wall pathology is blamed for dilatation and aneurysm formation in bicuspid aortic valve (BAV). MATERIALS AND METHODS: Aortic valve replacement (AVR) was performed on 78 adult patients with BAV. Patients were divided into two groups. Group I (n = 27) underwent only AVR. Group II (n = 51) underwent AVR and additional ascending aorta procedures such as Shawl-Lapel aortoplasty (n = 12) and tailoring aortoplasty (n = 9). Dacron wrapping was performed after both techniques were done. Ascending aorta replacement was done on 11 patients by using composite graft. Supracoronary graft replacement was performed in 3 patients after AVR. RESULTS: Ascending aorta diameter increment was 1.25 mm/year in normotensive and 2.80 mm/ year in hypertensive patients. Ascending aorta aneurysm (diameter > 55 mm) developed in eight patients in the postoperative period in group I. Ascending aorta dilatation did not develop in group II patients. Mean survival time +/- standard error (SE) was 128 +/- 11 and 99 +/- 4 months and survival possibility was 77.78% and 92.16%. Freedom from reoperation was 65.4% and 95.9% in 8 years in group I and group II, respectively. CONCLUSION: Aortic wrapping with or without aortoplasty has a beneficial effect not only in dilated ascending aorta but also in all nondilated BAV patients with normal-sized aortic diameter. Ascending aorta wrapping in BAV patients preserves the endothelial lining and prevents further dilatation, aneurysm formation, and dissection.     

A renal transplant recipient with pulmonary tuberculosis and visceral leishmaniasis: review of superimposed infections and therapy approaches

Visceral leishmaniasis (VL) is an acute or subacute disease that is almost invariably fatal if untreated. It is a rare disease in renal transplant recipients and frequently reported together with other infectious agents. A 39-year-old renal transplant patient was admitted to hospital for elective coronary surgery. In the post-operative period, he developed spiking fever and non-productive cough and his general condition deteriorated. While he was taking medication for non-specific pneumonia, a cavitary lesion occurred in his lung, and he had the diagnosis of pulmonary tuberculosis and antituberculous treatment was started. Despite treatment, his fever continued. As the patient developed pancytopenia and splenomegaly, a bone marrow aspiration was done. Evaluation of bone marrow aspirate indicated Leishmania parasites. He was successfully treated with a more intensive liposomal amphotericin (L-AmB). Complete cure was achieved during follow-up period of 10 months without clinical relapse. In the existence of fever and long-standing pancytopenia, VL should be suspected although the patient had another proved infection and did not live or visit an endemic area. L-AmB usage can be safely preferred for treatment of selected renal transplant recipients with VL as first-line therapy.     

Appropriate timing of surgical intervention after transmural acute myocardial infarction

OBJECTIVE: Recommended timing of coronary revascularization after transmural acute myocardial infarction ranges from immediate surgical intervention to repair 4 weeks after infarction. Such wide variation has created a dilemma in the management of these patients. The objective of this study was to delineate the optimal timing of revascularization after transmural acute myocardial infarction in a large and contemporary patient population. METHODS: We performed a retrospective multicenter analysis of 32,099 patients who underwent coronary artery bypass grafting as the sole procedure after transmural myocardial infarction between 1991 and 1996 by 179 surgeons at 33 hospitals in New York State. RESULTS: Overall hospital mortality for all patients who underwent coronary revascularization with a history of transmural myocardial infarction was 3.3%. Hospital mortality decreased with increasing time interval between revascularization and transmural acute myocardial infarction: 14.2%, 13.8%, 7.9%, 3.8%, 2.9%, and 2.7% for less than 6 hours, 6 hours to 1 day, 1 to 3 days, 4 to 7 days, 7 to 14 days, and greater than 15 days, respectively. Multivariate analyses of 43 potential risk factors suggests that revascularization within 3 days of transmural acute myocardial infarction is independently associated with mortality. CONCLUSIONS: Coronary revascularization within 3 days of a transmural acute myocardial infarction might be an added risk for mortality. In the absence of absolute indications for emergency surgical intervention, such as structural complications and ongoing ischemia, a 3-day waiting period before surgical revascularization should be considered.     

Prolonged donor ischemic time does not adversely affect long-term survival in adult patients undergoing cardiac transplantation

OBJECTIVE: With liberalization of donor eligibility criteria, organs are being harvested from remote locations, increasing donor ischemic times. Although several studies have evaluated the effects of prolonged donor ischemic times on short-term survival and graft function, few have addressed concerns regarding long-term survival. METHODS: Over the last 11 years, 819 consecutive adults underwent cardiac transplantation at Columbia Presbyterian Medical Center. Recipients were separated into the following 4 groups based on donor ischemic time: <150 minutes, 150 to 200 minutes, 200 to 250 minutes, and >250 minutes. Statistical analysis included Kaplan-Meier survival and Cox proportional hazard models to identify predictors of long-term survival. RESULTS: Donor ischemic time was 120.1 +/- 21.1 minutes for group 1 (n = 321), 174.1 +/- 14.7 minutes for group 2 (n = 264), 221.7 +/- 14.6 minutes for group 3 (n = 154), and 295.5 +/- 37.1 minutes for group 4 (n = 80) (P <.001). There were no significant differences in recipient age, donor age, etiology of heart failure, United Network for Organ Sharing status, or history of previous cardiac surgery among the groups (P = NS). Prolonged donor ischemic time did not adversely affect long-term survival, with actuarial survival at 1, 5, and 10 years of 86.9%, 75.2%, and 56.4% for group 1; 86.2%, 76.9%, and 50.9% for group 2; 86.4%, 71.0%, and 43.7% for group 3; and 86.7%, 70.1%, and 50.9% for group 4 (P =.867). There was no significant difference in freedom from transplant coronary artery disease among the 4 groups (P =.474). CONCLUSIONS: Prolonged donor ischemic time is not a risk factor for decreased long-term survival. Procurement of hearts with prolonged donor ischemic time is justified in the setting of an increasing recipient pool with a fixed donor population.     

The endogenous cannabinoid anandamide inhibits alpha7 nicotinic acetylcholine receptor-mediated responses in Xenopus oocytes

The effect of the endogenous cannabinoid ligand anandamide on the function of the cloned alpha7 subunit of the nicotinic acetylcholine (ACh) receptor expressed in Xenopus oocytes was investigated by using the two-electrode voltage-clamp technique. Anandamide reversibly inhibited nicotine (10 microM) induced-currents in a concentration-dependent manner (10 nM to 30 microM), with an IC50 value of 229.7 +/- 20.4 nM. The effect of anandamide was neither dependent on the membrane potential nor meditated by endogenous Ca2+ dependent Cl- channels since it was unaffected by intracellularly injected BAPTA and perfusion with Ca2+-free bathing solution containing 2 mM Ba2+. Anandamide decreased the maximal nicotine-induced responses without significantly affecting its potency, indicating that it acts as a noncompetitive antagonist on nicotinic acetylcholine (nACh) alpha7 receptors. This effect was not mediated by CB1 or CB2 receptors, as neither the selective CB1 receptor antagonist N-(piperidin-1-yl)-5-(4-chlorophenyl)-1-(2,4-dichlorophenyl)-4-methyl-1H-pyrazole-3-carboximide hydrochloride (SR 141716A) nor CB2 receptor antagonist N-((1S)-endo-1,3,3-trimethyl-bicyclo-heptan-2-yl]-5-(4-chloro-3-methylphenyl)-1-(4-methylbenzyl)-pyrazole-3-carboxamide (SR 144528) reduced the inhibition by anandamide. In addition, inhibition of nicotinic responses by anandamide was not sensitive to either pertussis toxin treatment or to the membrane permeable cAMP analog 8-Br-cAMP (0.2 mM). Inhibitors of enzymes involved in anandamide metabolism including phenylmethylsulfonyl fluoride, superoxide dismutase, and indomethacin, or the anandamide transport inhibitor AM404 did not prevent anandamide inhibition of nicotinic responses, suggesting that anandamide itself acted on nicotinic receptors. In conclusion, these results demonstrate that the endogenous cannabinoid anandamide inhibits the function of nACh alpha7 receptors expressed in Xenopus oocytes in a cannabinoid receptor-independent and noncompetitive manner.     

Fiberoptic flexible bronchoscopy via the laryngeal mask airway in children

The laryngeal mask airway (LMA) is a new device for controlling the airway during many procedures. Aside from its use in different kinds of surgical procedures, fiberoptic flexible bronchoscopy can also be performed easily with this mask in children under sedation. This procedure was performed via LMA in 36 children (aged 2-16 years) who suffered from different kinds of respiratory diseases and were seen at Hacettepe University Ihsan Do?ramaci Children's Hospital, Pediatric Chest Disease Unit, during a seven-month period. The procedure was performed with success and no complications occurred. To the best of our knowledge, this is the first report from Turkey on flexible bronchoscopic evaluation via LMA in children with different kinds of respiratory diseases. We suggest that this technique can be used safely.