Why do blood pressure and heart rate increase when you have dilated cardiomyopathy?

To keep up output. Cardiac output is the amount of blood (in liters) pumped out of the heart in one min. It is calculated as stroke volume x heart rate. Cardiomyopathy makes the heart pump less efficiently and so reduces the amount per stroke (stroke volume) so to make up for the drop in stroke volume, the heart beats faster. Blood pressure is not typical for dilated cm, but may be due to other concurrent condition.