The quad cab has a smaller back seat and a larger bed, the crew cab has a larger back seat and a smaller bed. To compare them you can go to http://www.ramtrucks.com/en/2011/ram_150... and select the Build My Own option from the bottom of the page.
Heart muscle thickening (called cardiac hypertrophy) can be a healthy response to exercise and pregnancy; however, it often occurs in people with high blood pressure, diabetes, heart failure and certain genetic conditions.
Hypertrophic heart disease is the abnormal thickening of the walls of the left ventricle. This can be congenital, related to valvular heart disease, autoimmune, or, most commonly, related to elevated blood pressure. The hypertrophy initially causes diastolic abnormalities. Because the thickened heart muscle is not as compliant as normal, the pressure inside the left ventricle may become elevated, and blood can back-up in the lungs.