I have recently been told that microvascular angina is the cause of my CHF. Presently, my EF is 40%. Can you tell me what you know about the microvascular angina as I can not find anything on it. I am taking Lasix and Imdur. The beta blockers make me have low blood pressure and I am asthamatic. Thank you in advance for your help.
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Dear Lin, thank you for your question. Microvascular angina refers to
myocardial ischemia (reduced blood flow to the heart muscle through the
coronary arteries) with macroscopically normal coronary arteries on an
angiogram. The coronary arteries originate from the aorta and are usually
3-4 mm in diameter. The arteries progressively taper to their distal terminal
branches which are less than 1 mm in diameter. On an angiogram, cardiologists
can see the opacified arteries to the level of 0.5 - 1.0 mm of resolution.
Thus, if there are no blockages in the arteries to that level of resolution,
the coronary arteries will be reported as being normal. However, if a stress
test has been done that demonstrates reduced blood flow to the heart muscle,
microvascular angina will be inferred if there are no macroscopic blockages
in the coronary arteries. Stress tests use radioisotopes to image blood flow
to the heart muscle via the coronary arteries and try to localize areas of
the heart muscle that are ischemic. Then, an angiogram provides a "road map"
of the arteries to try to correspond a blockage with the area of ischemia on
a stress test. I presume from what you've written, that you've had these tests
done to arrive at a diagnosis of microvascular angina. If you have not had these
tests done, then please write back with more information to help me elucidate
how your diagnosis was determined. The difficulty with microvascular angina
is that the presumed blockages (presumed because they can't be seen) can't be
treated with angioplasty or bypass surgery so only medications can be used.
Studies have shown inconsistent results with medications for the treatment of
microvascular angina. Congestive heart failure (CHF) results when the heart
muscle is damaged and doesn't pump efficiently. Heart muscle pumping function
is measured as the ejection fraction which is normally > 55%. Your EF is slightly
reduced which could be compatible with your diagnosis of CHF. Heart muscle
damage can be caused by heart attacks from blockages in the arteries and is
called ischemic cardiomyopathy and can also be caused by other processes where
the arteries are normal (dilated cardiomyopathy). Thus, you can see how an
angiogram is an integral test in determining the cause of CHF. I hope this
information helps.
Information provided in the heart forum is for general purposes only. Specific
diagnoses and therapies can only be provided by your physician.
