Your mother was wrong – what you don’t know can kill you, or atthe very least can make you really sick.

Take these three examples:

* Abdominal aortic aneurysm. This one can literally be a killer.If your aorta ruptures, there’s a very good chance you won’t livethrough it. Of those who suffer abdominal aortic ruptures, 85percent don’t survive.

* Peripheral arterial disease, or PAD for short. Often found inyour legs, the disease – which is essentially a buildup of plaquethat causes arteries to narrow and harden – can also be a sign ofworse things to come. People with PAD are also at risk for heartattack, or stroke.

* Carotid artery disease. This too is caused by a buildup ofplaque in arteries, in this case the two carotid blood vessels thatfeed blood to your brain. One consequence: the very realpossibility of a stroke.

Of the three, the least is known about the exact causes ofabdominal aortic aneurysm. But medical science does know what riskfactors are involved that can lead to it, and scientists also knowthat the larger the aneurysm the more likely it is to rupture.

If the worst happens, and the vessel ruptures, you can bleedinternally. If the aorta ruptures, you’ll know pretty quickly.Among the symptoms if that happens:

* Severe, sudden pain in your abdomen or back, groin, buttocksor legs

* Nausea, along with clammy skin

* Increased heart rate

* Shock

Fortunately, there are screening methods that could give youtime to be diagnosed and treated before disaster strikes.

The Society for Vascular Surgery says the most common stepsare:

* An ultrasound test of your abdomen

* A CT exam (CT stands for Computed Tomography)

* An MRI, more technically called a Magnetic Resonance Imagingexam.

The ultrasound test is the simplest and is safe, without anyradiation exposure. It also only takes a few minutes.

Another serious medical issue often not screened for is PAD, thedisease that shows up in your legs when blood vessels getconstricted by fat and cholesterol. It can cause pain and numbnessin your legs, and if you get an infection in that part of yourbody, you’ll have a tougher time fighting it off. It is also amarker for coronary artery disease, heart attack and stroke.Unfortunately, you may not have any symptoms at all. PAD can besilent.

Doctors often look to lifestyle changes to treat PAD. Quittingsmoking is first on the list, followed by lowering blood pressureand cholesterol, lowering blood sugar levels and being physicallyactive. Sign up for the free health e-newsletter by Life Line Screening that can help getyou on the right track for healthy living today.

The most common screening test for PAD is called theankle-brachial index (ABI). The ABI compares the blood pressure inyour arm to the blood pressure in your ankle. The test determinesif the pressure in your ankles is the same or greater than that inyour arms. If it is less, you may have a problem.

Another key problem area involves plaque buildup in the two mainblood vessels that feed your brain, your carotid arteries. In thiscase, the results can also be devastating: a stroke. More than halfthe strokes in the United States are caused by carotid arteryissues. Watch an overview video about stroke riskcourtesy of Life Line Screening.

Alas, you might not know you’re in danger until the worsthappens, either when the arteries are severely blocked, or a strokeactually occurs. To protect yourself, doctors advise living ahealthier lifestyle by keep your weight in check, quitting smokingand getting regular exercise.

Medically speaking, the treatments range from surgery on yourartery to remove the plaque in an attempt to improve the blood flowto your brain, to the less invasive angioplasty in which a stent inplaced in the artery to achieve the same result.

As with the other arterial diseases, there are severalscreenings to help you head off a major crisis by learning what ishappening inside your carotid arteries before a major strokeoccurs.

Included is a test called a carotid ultrasound, which helpsdoctors use sound waves to create a picture of your arteries. Thereare also diagnostic tests such as a carotid angiography, which is atype of X-ray in which doctors inject a dye into a vein to track itthrough your system. And there is an MRA (Magnetic ResonanceAngiography) to help doctors diagnose whether you have a problem.It uses a magnet and radio waves to provide your doctors withimages.

You should know that typically your health insurance won’t payfor vascular screening tests if you have no symptoms, although theycan be life-saving screenings. The best course for you in that caseis to talk to your doctor about what is available to you and seekscreenings from a community-based organization which usuallyprovides screenings at a reasonable cost. Join Life Line Screening onFacebook to follow what people are saying about theirexperiences with community-based screening events.