Mitral valve stenosis can be treated using percutaneous (keyhole), minimally invasive or standard surgery. Keyhole techniques, where a balloon is inflated inside the valve via a wire in the groin (balloon valvotomy), are the first line of treatment if the mitral valve is not heavily calcified. This can be repeated as needed over several years.
You can only mount a tire of equivalent load or higher load than indicated for your vehicle. The higher the tire's load index number, the greater its load carrying capacity. Typically, the load indexes of the tires used on passenger cars and light trucks range from 70 to 130. See full table
With most on-highway truck tires now rated for 75 mph (speed rating L for the ISO LI/SSY rating), 75 should be a safe speed for tires if the correct pressure is maintained. Speeds above 75 may require additional pressure or reducing the load on the tire.