Outcome of left heart mechanical valve replacement in West African children - A 15-year retrospective study

Abstract

BackgroundThe West African sub-region has poor health infrastructure. Mechanical valve replacement in children from such regions raises important postoperative concerns; among these, valve-related morbidity and complications of lifelong anticoagulation are foremost. Little is known about the long-term outcome of mechanical valve replacement in West Africa. We sought to determine the outcome of mechanical valve replacement of the left heart in children from this sub-region.MethodWe conducted a retrospective review of all consecutive left heart valve replacements in children (< 18 years old) from January 1993 - December 2008. The study end-points were mortality, valve-related morbidity, and reoperation.ResultsOne hundred and fourteen patients underwent mitral valve replacement (MVR), aortic valve replacement (AVR) or mitral and aortic valve replacements (MAVR). Their ages ranged from 6-18 years (13.3 ± 3.1 years). All patients were in NYHA class III or IV. Median follow up was 9.1 years. MVR was performed in 91 (79.8%) patients, AVR in 13 (11.4%) and MAVR in 10 (8.8%) patients. Tricuspid valve repair was performed concomitantly in 45 (39.5%) patients.There were 6 (5.3%) early deaths and 6 (5.3%) late deaths. Preoperative left ventricular dysfunction (ejection fraction < 45%) was the most important factor contributing to both early and late mortality. Actuarial survival at 1 and 15 years were 98.1% and 94.0% respectively. Prosthetic valve thrombosis occurred in 5 patients at 0.56% per patient-year. There was 1(0.9%) each of major bleeding event and prosthetic valve endocarditis. Two reoperations were performed at 0.22% per patient-year. Actuarial freedom from reoperation was 99.1% at 1 and 10 years, and 85.1% at 15 years.ConclusionMechanical valve replacement in West African children has excellent outcomes in terms of mortality, valve-related events, and reoperation rate. Preoperative left ventricular dysfunction is the primary determinant of mortality within the first 2 years of valve replacement. The risk of valve-related complications is acceptably low. Anticoagulation is well tolerated with a very low risk of bleeding even in this socioeconomic setting.

Experience with Prosthetic Valve Replacement in Indigents with Rheumatic Heart Disease in Nigeria: 10-Year Follow-Up

“…On the other hand two recent reviews from SSA based on their experience both recommended mechanical valves. Edwin et al [6] from Ghana in a 9.1 years follow up of 114 patients undergoing mechanical heart valve replacement with St. Jude and Sorinmonoleaflet valves, observed valve thrombosis in 5 patients, 1 major bleeding, 1 prosthetic valve endocarditis, 2 reoperations and 4 pregnancies without complications. Similarly Williams et al [7] report on 438 South African patients with On-X valve, poorly anticoagulated at follow up of 1.7 years, observed low incidence of hemorrhagic and thrombotic complications and seven full term pregnancies.…”

“…The only patient in our series who had ablation has remained in sinus rhythm for 9 years. While the two reviews on mechanical valves [6] [7] from SSA reported good long and short term results respectively, the health care infrastructures in both Ghana and South Africa are better developed and organized than Nigeria and several other SSA countries, making their results more difficult to reproduce. Another factor likely to favor tissue valve in the horizon is a promising novel low cost stented pericardial valve designed for developing countries like in SSA reported by Legg et al [11] It features a clip in mechanism that secures the valve assembly into the sewing ring stitched independently of the frame and leaflets.…”

A review of valve surgery for rheumatic heart disease in Australia

“…The choice of valve procedure is likely to be informed by a combination of patient, health practitioner choice, demographic and disease factors. A mechanical valve has long term durability providing therapeutic anticoagulation can be achieved compared to a bioprosthetic valve which is likely to degenerate over time [ 1 , 23 , 32 , 33 ]. Mechanical valves may therefore be preferred in younger patients so as to avoid later re-operation.…”

A review of outcome following valve surgery for rheumatic heart disease in Australia

“…Surgical intervention remains an important treatment modality for those with more severe forms of RHD, yet disparities exist in access to and outcomes following RHD surgery [ 7 ]. Factors which have been identified as being associated with outcomes following valve surgery in patients with RHD-related valve disease include age [ 8 – 11 ], pre-operative clinical status [ 8 – 10 , 12 – 15 ], pre-existing atrial fibrillation (AF) [ 13 , 16 , 17 ], left ventricular function [ 12 – 14 , 18 , 19 ] and the nature of the underlying valve lesion [ 10 , 12 , 13 , 20 ].…”