- angina-line chest pain during exertion
- characteristic ECG changes during exercise testing
- normal coronary arteries on cardiac catheterization
- no inducible coronary artery spasm during cathterization
What is the cause of CSX?
Nobody knows for sure, but there are two major working theories. The first holds that CXS is caused by a poorly-defined disorder of the tiny arteries in the heart muscle (arteries too small to be seen during catheterization). The second suggests a certain "hypersensitivity" to cardiac pain. It is certainly possible (and even likely) that many patients with CSX have both of these proposed abnormalities.Who gets CSX?
While CSX can affect anyone, by far it is seen most often in younger (i.e., pre-menopausal) women. Further, doctors generally believe there is a strong association between CSX and certain "psychiatric disorders," such as panic attacks. (Note: DrRich is one of those who believes that most patients with panic attacks are not suffering primarily from a psychiatric disorder, but instead have one of the dysautonomias. The dysautonomias can certainly lead to anxiety and depression, but such associated conditions are most often secondary, and not primary. CSX has also been linked to other dysautonomia syndromes, such as fibromyalgia and inappropriate sinus tachycardia, raising the possibility that some patients with CSX might have a disorder of the small blood vessels within the heart muscle secondary to autonomic dysfunction.)How is CSX diagnosed?
There is no test that definitively "proves" that a patient has CSX. Indeed, the diagnosis is made primarily by excluding all other causes of chest pain. However, several tests can be helpful in making the diagnosis. These include:- exercise testing, which usually reproduces the pain and shows changes on the ST segments of the ECG.
- cardiac catheterization, which shows normal visible coronary arteries and no inducible spasm
- MRI scanning has been used in research centers to demonstrate abnormal blood flow in the heart muscle in patients with CSX after various provocative testing (such as adenosine or dobutamine infusions.) MRI scanning is not routinely done to make a diagnosis, but has offered the strongest evidence to date that patients with CSX have a true physiological abnormality associated with their chest pain.
How significant is CSX?
Fortunately, most patients with CSX appear to have a very good prognosis. Long-term follow-up studies have not shown an increased statistical risk for these patients to develop heart attacks or cardiomyopathy (i.e., heart muscle disease and heart failure.)How is CSX treated?
Since CSX does not appear to be associated with long-term cardiac disease, the chief goals of therapy are 1) reassurance, and 2) pain control.Pain control can often be achieved by using one or more of the following drugs: nitrates, calcium channel blockers, beta blockers, or imipramine. Usually, patients are given nitrates to take as needed for chest pain. Calcium channel blockers are usually added if nitrates are insufficient. Those patients who display an increase in sympathetic tone (i.e., those who have signs of Inappropriate Sinus Tachycardia) often respond well to beta blockers. Finally, if none of these drugs (alone or in combination) are effective, a trial of imipramine can be used.
In post-menopausal women with CSX, hormone replacement therapy can be effective in controlling symptoms. However, such symptom control must be weighed against the recently discovered negative effects of HRT.
