Results of prosthetic valve replacement for aortic stenosis

Background: Aortic valve replacement with mechanical valves is associated with a small but constant risk of valve thrombosis and thromboembolic and hemorrhagic complications. The surgical outcome of patients with Aortic Stenosis who had aortic valve replacement with mechanical valves is reported here. Methods: Between January 1990 and October 1999, 275 patients underwent prosthetic valve replacement for isolated aortic stenosis. The age ranged between 13 years and 75 years and 230 were males. The cause of aortic stenosis was rheumatic in 185 patients (67.3%), followed by bicuspid aortic valve in 75 patients (27.3%) and degenerative in 15 patients (5.4%). Results: The early mortality was 1.5%. The follow up was 96% complete and ranged from 1 to 104 months (mean 54±24.5months). Six patients (2.2%) developed prosthetic valve endocarditis. Paravalvular leak occurred in 3 (0.9%) patients. Valve thrombosis occurred in 10 patients (1.0% per patient year). The actuarial survival was 81±7% at 5 years and 64±13% at 8 years. Event free survival was 40±14% at 8 years. Conclusion: With current operative techniques and myocardial preservation aortic stenosis patients are at low risk for surgery. However, long term survival is limited due to prosthesis related complications.     

Homograft saphenous vein versus polytetrafluoroethylene graft for modified Blalock -Taussig shunt

Back ground  Modified Blalock-Taussig shunt is an important initial palliation in a selected subset of patients. This randomized controlled study was conducted to evaluate and compare PTFE and homograft saphenous vein as a conduit for this purpose. Patients and Methods  Thirty patients were prospectively randomized to receive either a Polytetrafluoroethylene (PTFE) or an antibiotic preserved homograft saphenous vein as conduit. Early results were analysed and compared. Results  Mean graft size was 3.93 mm±0.53 and 4.2 mm±0.53 in the PTFE and vein group respectively. There were 3 hospital deaths in the vein group and none in the PTFE group. There were 2 early and no late shunt thromboses in PTFE group while 1 early and 2 late thrombosis occurred in vein group. These differences were statistically insignificant. The incidence of post-operative bleeding, peri-graft seroma and operative time was less in vein then PTFE group. Palliation on follow-up was comparable in both groups. Conclusion  This study failed to demonstrate any benefit of homograft saphenous vein over PTFE graft in terms of thrombotic complications and mortality. There was however less bleeding and peri-graft seroma formation in the Saphenous vein (SVG) group. Further studies with greater number of patients and longer follow-up are required to demonstrate the superiority of either of these conduits.     

Global Unmet Needs in Cardiac Surgery

More than 6 billion people live outside industrialized countries and have insufficient access to cardiac surgery. Given the recently confirmed high prevailing mortality for rheumatic heart disease in many of these countries together with increasing numbers of patients needing interventions for lifestyle diseases due to an accelerating epidemiological transition, a significant need for cardiac surgery could be assumed. Yet, need estimates were largely based on extrapolated screening studies while true service levels remained unknown. A multi-author effort representing 16 high-, middle-, and low-income countries was undertaken to narrow the need assessment for cardiac surgery including rheumatic and lifestyle cardiac diseases as well as congenital heart disease on the basis of existing data deduction. Actual levels of cardiac surgery were determined in each of these countries on the basis of questionnaires, national databases, or annual reports of national societies. Need estimates range from 200 operations per million in low-income countries that are nonendemic for rheumatic heart disease to >1,000 operations per million in high-income countries representing the end of the epidemiological transition. Actually provided levels of cardiac surgery range from 0.5 per million in the assessed low- and lower-middle income countries (average 107 ± 113 per million; representing a population of 1.6 billion) to 500 in the upper-middle-income countries (average 270 ± 163 per million representing a population of 1.9 billion). By combining need estimates with the assessment of de facto provided levels of cardiac surgery, it emerged that a significant degree of underdelivery of often lifesaving open heart surgery does not only prevail in low-income countries but is also disturbingly high in middle-income countries.