Risks and complications of valve replacement
Heart valve replacement requires open-heart surgery which intrinsically carries a risk of haemorrhage, infection, sudden death, stroke, cardiac arrhythmia (irregular heart beat) and renal failure. The death rate from the procedure averages 2% to 5%.
All prosthetic valves are likely to precipitate thrombosis around the site of the valve and lifelong anticoagulation therapy is essential for all patients. However, even with effective anticoagulation, thrombo-embolic events resulting from part of a clot breaking away into the general circulation are not uncommon and symptoms indicating embolism to the brain can be expected in1-2% of cases.
Prosthetic heart valves have a limited life span. Mechanical valves are fairly durable but are more likely to suffer from clotting and calcification. Natural prostheses are less likely to induce clotting but are more likely to wear out and have a life span of only around 10-15 years.
Failure of the prosthesis can result from gradual occlusion from fibrosis or thrombus formation or it can fail more dramatically due to breakage of components. This can cause a rapid onset of the effects of valve incompetence with significant risk of mortality.
Post-operative infection at the site of insertion of the valve with associated endocarditis can have disastrous consequences. All patients should have antibiotic cover over the period before and following surgery. Infective endocarditis rarely responds to antibiotics alone and further valve replacement is almost always necessary.
