First, measure: how echo grades a valve
Before anyone touches a valve, they measure it, and the workhorse tool is echocardiography — ultrasound of the beating heart. It shows the leaflets moving in real time, while Doppler measures how fast blood races across the valve. For a stiff valve, high velocity means a tight opening; the cardiologist converts that into a valve area and a pressure gradient to grade the stenosis as mild, moderate, or severe. For a leaky valve, Doppler maps the backward jet to estimate the regurgitant fraction — how much of each beat is wasted flowing the wrong way.
These numbers, combined with whether the person has symptoms and how the left ventricle is coping, decide the timing. The art of valve disease is choosing the moment: act too early and you expose someone to a procedure they did not yet need; act too late and the heart muscle is permanently damaged. Echo is repeated over years precisely to catch the turning point.
Repair, replace, or thread one in
There are three broad ways to fix a valve. The first is repair — keeping the patient's own valve and reshaping it, for example tightening a stretched mitral ring or trimming a billowing leaflet. Repair is the preferred answer for many leaky mitral valves because the native tissue, when it can be saved, tends to last and avoids a foreign valve altogether. A valvuloplasty — stretching a narrowed valve open with a balloon — is a related, less invasive repair used mainly for rheumatic mitral stenosis.
When a valve is too damaged to repair, it is replaced with a prosthetic valve. Traditionally this meant open-heart surgery on a heart stopped and supported by a bypass machine. The newer revolution is doing it without opening the chest: in TAVR (transcatheter aortic valve replacement), a collapsed valve is threaded up through an artery in the groin and expanded inside the old one, which it crushes aside. TAVR transformed care for older or frailer patients who once had no safe option, and a similar transcatheter clip can pinch a leaky mitral valve without surgery.
Mechanical or tissue: a lifelong trade-off
Whenever a valve is replaced, one choice follows: a mechanical valve made of durable materials, or a tissue (bioprosthetic) valve made from treated animal tissue. The trade-off is honest and worth understanding. A mechanical valve lasts essentially a lifetime but its surfaces tend to form clots, so it requires lifelong warfarin and the regular blood tests and bleeding risk that come with it. A tissue valve usually needs no long-term blood thinner, but it wears out over roughly ten to twenty years and may need replacing.
So the decision often turns on age and life circumstances. A younger person may accept lifelong warfarin to avoid a second operation; an older person, or someone for whom blood thinners are risky, may prefer a tissue valve and accept that it might be replaced later — increasingly via a catheter, valve-inside-a-valve. Whichever valve is chosen, every prosthesis carries a raised risk of infective endocarditis, so meticulous dental and skin care and prompt treatment of infections become a lifelong habit.
- Measure the valve with echo and Doppler; grade the stenosis or regurgitation.
- Weigh symptoms and ventricular function to choose the moment to act.
- Decide repair vs replacement, and surgical vs transcatheter, with the heart team.
- If replacing, choose mechanical (durable, needs warfarin) vs tissue (no long-term blood thinner, may wear out).