Diagnosing heart disease in women can be a challenge. Atypical chest pain and differences in micro vascular function are more common in women, as are mitral valve prolapse and non coronary chest pain syndromes. Noninvasive testing has a higher false-positive rate in women than in men, largely because of lower pretest likelihood of disease.
When you think of heart disease and heart attacks, you may conjure up images of older, overweight men being affected. However, women are affected just as frequently. Most women with coronary artery disease (CAD) have a reasonably typical form of the disease. But, importantly, women are, on average, about 10 years older than men with CAD. These women have roughly the same outcomes as men, when matched age for age – at least when their CAD is diagnosed and treated in a timely fashion. The majority of women with CAD fall into this “older patient, typical CAD” pattern.
However, there are three aspects of CAD in women that are more common to women than men, and when they occur they often lead to missed diagnoses and inadequate therapy:
- The symptoms of CAD can be different.
- The usual diagnostic tests are more likely to give the wrong answer.
- The disorders affecting the coronary arteries can be different, especially in younger women.
These differences, coupled with the false notion that women just don’t get heart disease, contribute mightily to critical delays in diagnosis and treatment – and ultimately, to disability and death. Let’s look at these factors more closely:
When women have angina (chest pain due to heart disease), they are more likely than men to experience “atypical” symptoms, such as a hot or burning sensation, or even tenderness to touch, in the back, shoulders, arms or jaw; often they have no chest discomfort at all. Any good doctor will think of angina whenever a patient describes any sort of fleeting, exertion-related discomfort located anywhere above the waist, and they really shouldn’t be thrown off by “atypical” descriptions. However, because many doctors persist in believing that CAD is uncommon in women, they are all too likely to write such symptoms off to mere musculoskeletal pain or gastrointestinal disturbances.
Heart attacks also tend to behave differently in women. Frequently they experience nausea, vomiting, indigestion, shortness of breath or extreme fatigue – but no chest pain. Unfortunately, these symptoms are easy to attribute to something other than the heart. Women also are more likely than men to have “silent” heart attacks – that is, heart attacks without any acute chest pain and that are diagnosed only at a later time when more cardiac symptoms occur.
Diagnostic tests for CAD can be misleading in women. The most common problem is seen with stress testing – in women, the ECG during exercise can often show changes suggesting CAD, whether CAD is present or not, making the study difficult to interpret. Many cardiologists routinely add something known as an echocardiogram or a thallium study when doing a stress test in a woman, which greatly improves diagnostic accuracy.
In women with typical CAD, coronary angiography is every bit as useful as in men; it identifies the exact location of any plaques, and guides therapeutic decisions. However, in women with atypical coronary artery disorders, angiograms often appear entirely normal, a result that can be very misleading.
At least three atypical coronary artery disorders occur in women, usually in younger pre menopausal women. Each of these conditions produce chest pain with “normal” coronary arteries (that is, coronary arteries that appear normal on angiogram unless special care is taken.)
For several years, cardiologists have known that heart disease in women can be quite different than it is in men. Women’s symptoms may be different, the diagnostic tests that are used for CAD can give the “wrong” answer in women and the underlying disease itself can be quite different.
The new evidence suggests that in women under 50 years of age, plaque rupture is often not the cause of the blood clot. Instead, the clot may be triggered by erosion of the blood vessel wall.
What’s the difference between a rupture and an erosion? Well, a rupture of a plaque is like a pimple that pops open. But an erosion is more like a shallow ulcer – the plaque associated with an erosion may be quite small or there may not be a plaque at all. It is becoming increasingly obvious that CAD in younger women is very often a different disease than the “classic CAD” that is seen in men and in older women. The recognition of this fact is leading, at last, to efforts to gain a full understanding of those differences and to develop more effective strategies for treatment.
Studies have supported the notion that women with Syndrome X (angina and “normal” coronary arteries) actually do have coronary artery pathology involving “micro vessels” – the small branches of the coronary arteries that are not visualized by cardiac catheterization.
In women with Cardiac Syndrome X, despite the fact that they describe symptoms typical of angina and often have ECG changes suggesting coronary artery blockages, are found to have “normal” appearing coronary arteries on catheterization. These women are often told they are normal, and that their symptoms are due to anxiety, so go away and leave the cardiologist alone.
The diagnosis of female-pattern CAD can be made definitively with a relatively new technique called intravascular ultrasound (IVUS) imaging. IVUS (which is not available in most hospitals) requires inserting a specialized catheter into the coronary artery that uses ultrasound to visualize the wall of the artery from within. The diffuse plaques of the remodeled artery can be identified in this way. In a recent study, more than half the women who had angina with “normal” coronary arteries had plaques identified using IVUS. Female-pattern CAD should be suspected in any woman who has had angina or an MI, who has risk factors for CAD, but who has “normal” coronary arteries on angiography.
Because the narrowing of the coronary arteries in female-pattern CAD is diffuse, therapies aimed at relieving localized obstructions – such as angioplasty, stents, and bypass surgery – do not apply. Instead, therapy must be medical. Optimal treatment for this condition has yet to be defined, but a multi-pronged approach seems the best at this time, and should include aggressive risk factor modification, therapy to reduce the risk of clotting (aspirin,) and drugs to protect the heart muscle itself (beta blockers and possibly ACE inhibitors). Researchers have now focused their attention on female-pattern CAD, and a better understanding of this condition and its treatment is very likely in the foreseeable future.