Good point. I haven't heard "weak vein" as a medical condition that pertains to the heart so I assumed it was vessel.
You are correct. There is less pressure, but veins have valves that act as one-way flaps (fight against gravity). These valves prevent the blood from flowing backwards as it moves up the legs. If the one-way valves become weak, blood can leak back into the vein and collect there. This problem is called venous insufficiency or weak vein.
As it pertains to heart attack and/or stroke. Severe venous insufficiency is pooling of blood in the veins that slows the return of blood to the heart. This condition can cause blood clots and severe infections. Blood clots can be very dangerous because they can move from leg veins and travel to the lungs. Blood clots in the lungs are life-threatening because they can block the heart and lungs from functioning. An aneurysm of a leg vessel is a varicose.
Blood returning to the heart from the heart, lungs, etc. is more complex and doesn't depend on individual veins to move blood against gravity, etc. The factors involved are the determinants of diastolic function. Myocardial relaxation is an active process influencing the isovolumic relaxation phase and part of the early filling phase. Factors effecting myocardial relaxation include elastic recoil of the myocardium (heart muscle) which creates a “SUCTION” after systole (pumping). I'm at a loss how the term heart vein comes into play!
My mother told me that the problem was a weak vein though she might have meant blood vessel or artery. I hope what she has isn't an aneurysm in an artery.
I had wondered if the OP mean artery instead of vein.,, with the lower pressure in the vein making vein aneurysms so rare and also because if a vein ruptured, how would that lead to heart attack?
Anyways, since there is little actual discussion, I threw that in.
Speaking of arteries, magnesium is said to strengthen the walls, IIRC.
A weak vessel is often referred to medically as an aneurysm. The vessel bulges due to intravessel pressure and a weak vessel wall. Treatment is to control blood pressure and aneurysm is usually caused by high blood pressure.
The aneurysm can grow and become a risk to rupture and my require surgery.