You've read about the current situation in the previous post. I had a thalium stress test this past week in order to assess further the results of the calcium heart scan. I'll be meeting with the specialist in early February. I'll likely schedule a second calcium heart scan in the summer of 1011 to see whether my efforts have stabilized calcium build up.
All of these tests are indirect measures used to determing heart risk. In fact, right now I am asymptomatic. My O2Max is excellent for my age (41); morning heart rate (52); good heart rate variability (HRM); no chest pains, shortness of breath; dizzyness, etc. The challenge is to make the most of these indicators and others to manage risk prudently. For example, I didn't train enough for the last Cycle Oregon and "blew it out" when I did the ride -- probably not the most prudent approach. At the very least I'll increase my training mileage before the race so that there is not a big discontinuity between the race milage and my average race mileage.
So it's helpful to know the real state of my vascular system before emabarking on some demanding exercise adventures (Cycle Oregon, hiking across England, doing the Grand Canyon Rim to Rim to Rim again).
None of the tests I've mentioned actually involve looking into my vascular system. So they are "indirect". (An angiogram would provide a view, but that is invasive and not without its own risk.)
The calcium heart scan can "slice" the heart into 60 cross-sections and build up a view of the calcium in your major heart arteries. You are not looking at the plaque directly, only the calcium which is very highly correllated with plaque. On this test it showed that I have a one in five chance of a major heart incident soon if no changes occur. Some studies show that I am 21 times more likely within a specified time (say a year) to have a major heart incident if I don't do anything. I take this seriously.
There are other indicators, blood pressure is a good one. 130/80 is the new standard (Pre-hypertension). Another is the CRP (C-Reactive Protein) test which tests for inflamation, where inflamation is highly correlated with plaque build up.
The thalium stress test is probably not going to tell me anything more than the calcium heart scan. I'll let you know about this when I see the specialist in February. It does show blood flow under modest stress. It compares, as I understand it, blood flow in a relaxed state with blood flow under modest exercise. A different color dye is injected when you are on the treadmill. The key is to see which arteries are totally blocked, or blocked in one state (relaxed) and not in another. The calcium heart scan theoretically can show this, but the "real-life" blood flow situation perhaps can show more. We'll see.
During my debriefing after the heart scan, the nurse said that "70% is in the genes." If change is to be made, it has to occur in the remaining 30%. There are two areas 1) Lifestyle and 2)Medication.
Lifestyle consists of diet and exercise. I'm working on the former and have lost about 4 pounds since the summer. I plan to continue losing slowly and have a goal of a total of 8 pounds by March when I take the next lipid panel.
In terms of exercise, I plan to up my mileage for the September, 2010, Cycle Oregon. Also it should be possible to do something each day, including stretching, some (new) elliptical work, and some running cross-training. These are "tweaks" that might help. It's possible I might be able to up my O2Max (Polar version) to 44 by March and perhaps higher in the summer as my bike milage rises.
But the re-take of the calcium heart scan wouldn't occur until a year from this summer, so I would not have a smaller scan number to reinforce my efforts (if it happens at all) until then. So I'll have to make do with weight loss, cycle and other miles, maybe calories, higher O2Max, etc.