mixed valve disease

Sometimes a single valve has two problems at once: it is both too tight to open fully and too leaky to close completely. This combination of stenosis and regurgitation in the same valve is called mixed valve disease — a faulty door that neither swings open all the way nor latches shut.

The two faults can pile their burdens together. Stenosis makes the upstream chamber push against high resistance, while regurgitation makes it pump extra leaked-back volume, so a heart with mixed disease may struggle more than the individual gradient or leak alone would suggest. One component often predominates, and figuring out which one drives the patient's problem shapes the plan.

A frequent example is rheumatic mitral disease, which classically fuses and scars the valve to produce both narrowing and leakage. Mixed aortic valve disease is also common, especially with calcific or bicuspid valves. Grading mixed disease is harder than grading a pure lesion, because the usual single-number thresholds were defined for isolated stenosis or isolated regurgitation, so echocardiography is interpreted with extra care.

Because severity criteria are designed for pure lesions, mixed disease requires nuanced, individualized assessment rather than mechanical application of thresholds.