Dr Malik is a recognised expert in treating valve problems.
This month he and his colleagues have published the UK experience of plugging leaks that can occur around artificial valves. If you have such a leak, another operation to replace the Valve is high risk. Plugging it via a small needle puncture in the leg might be safer and effective.
http://circ.ahajournals.org/content/early/2016/08/31/CIRCULATIONAHA.116.022684