How are high blood pressure and heart failure connected?

Heart - Hypertension. Hypertension can cause heart failure by causing strain on the heart muscle due to the excess work of pumping into high pressure arteries, or by causing the tiny arterioles that bring blood to the heart muscle and lining to narrow and become stiff, thus damaging heart function due to low blood supply.
LV failure. Chronic high blood pressure (or hypertension) leads to compensatory left ventricular hypertrophy and remodeling. If hypertension remains untreated, it may produce left ventricular systolic and diastolic failure and congestive heart failure. Hypertension is also associated with coronary artery disease and an increased risk for certain abnormal heart rhythms that may contribute to heart failure.