What is the connection between hypertension and thromboembolism?

No relation. Hypertension as a rule affects the arteries not the veins...The venous system is not directly impacted by hypertension...Venous hypertension is a different disease entity.
Indirect. Hypertension can result in cardimyopatthy. This i. Turn can lead to intracardiac clot that can subsequently embolize.