Does angina increases the odds of heart attack? If I had an angina attack over the weekend, does that mean I'm at increased risk of having a heart attack?
Very possibly. Heart attack risk increases when angina accelerates. If your angina is occurring with increased frequency, duration, severity or occurs at a lower workload, you should see your doctor as your risk is increased. If your angina came on over the weekend doing something that always causes it, your risk is unchanged.
If. If you experience angina at rest, or are developing it frequently with minimal exertion, then you are having what is called unstable angina. This does mean you are at an increased risk for having a heart attack, and you should be evaluated immediately. Unstable angina falls in a category of what are called acute coronary syndromes. Unstable angina indicates that atherosclerotic plaques in the artery may be unstable and at risk of rupturing and completely blocking the artery. If this occurs, this causes a heart attack. You should contact your cardiologist's office for further direction, or if experiencing unstable angina after hours then you should be evaluated in an emergency room.
What exactly does "noncritical disease" of "up to 20 percent" mean on heart cath report? Why would this be low risk for heart attack/unstable angina?
Blood flow. For a stenosis to be significant, it has to affect blood flow. That does not occur until the stenosis reaches about 70%, at which point it is considered critical. Lesions around 50% are high risk due to potential risk for sudden occlusion. Lesions in the 20% range, when followed proved to be low risk. You should not have angna from this lesion, and it doesn't normally cause a heart attack.
Low % narrowing. At 50% diameter or 75% area narrowing there is a reduction f flow which is then a critical stenosis and may lead to ischemia of the end organ such as heart, brain, kidney etc.
Not hemodynamically. Significant, however, this does not mean no risk as 2/3 heart attacks are caused by blockages less than 50%. Talk to your physician about reducing your long term risk as you do have heart disease.