Early intervention isn’t always best

A few years back (well, 15 years actually), my brother had a mild heart attack.

It had already become common practice to rush patients like him into the cardiac catheter lab to check if there was a blockage in one or more of the blood vessels that feed the heart, and then to do angioplasty, otherwise known as the roto rooter of cardiac blood vessels. Cardiac catheterization followed by “revascularization” (either through angioplasty or coronary artery bypass surgery) has become the norm for heart attack victims.

It has also become the norm for those with what is called “acute coronary syndrome,” often referred to as a “mild heart attack.” These patients have the same symptoms — the crushing chest pain, or the squeezing pain that radiates down the left arm or up to the jaw. Their EKGs don’t show that they are in the midst of an acute heart attack, although there are often subtle changes. And blood tests indicate that there might be some early damage happening, a sign of ischemia, or poor blood flow.

These patients are at risk for having a real, honest-to-God heart attack in the near future. There are lots of studies showing that this early invasive strategy is beneficial.

But does it reduce deaths among this group? That wasn’t clear. So researchers in the Netherlands set out to find out if the early invasive strategy reduced overall mortality.

They compared it to what they called a selectively invasive strategy. This strategy involved the immediate use of aspirin and powerful clot-dissolving drugs, along with drugs to lower cholesterol, just like the early invasive strategy group got. But they only went on to the cath lab if their pain continued or they showed other signs that things were going in the wrong direction.

Over a one-year period, 99 percent of patients in the early invasive strategy group got a heart cath, 61 percent had an angioplasty, and 18 percent had coronary artery bypass surgery, most within the initial hospitalization, for a 79 percent revascularization rate. In the selectively invasive strategy group, only 67 percent had a heart cath, 40 percent had angioplasty, and 14 percent had coronary artery bypass, for a 54 percent revascularization rate by one year.

The researchers were pretty sure that they were going to find that the early invasive strategy was the best for reducing deaths and future heart attacks, especially since earlier studies had said it was. But this is what science is all about: You think something is so (in this case the early invasive strategy is best), and you set out to prove it. And sometimes, the results you get surprise you.

And so it was for the Dutch researchers. They found that there was no difference in mortality between the two groups after one year. The mortality rate was low, however, even though these patients are considered high risk. This may be because of the aggressive drug therapy used in both groups.

Compared to earlier studies, these drugs are only getting better.

There were more heart attacks in the early invasive strategy group, particularly during hospitalization, confirming the findings in an earlier study that there is a risk associated with early revascularization.

The results of this study were such a surprise that they aren’t likely to change the way things are done here, especially since the American Heart Association and the American College of Cardiology advocate the early invasive strategy. But it has changed the way some doctors are treating acute coronary syndrome in the Netherlands.

One problem for us in the United States is that patients in the selectively invasive strategy group were kept in the hospital for 11 to 12 days so they could be observed, and that just won’t happen on this side of the Atlantic. Still, it is intriguing to think that there are a select group of patients who could be treated safely with a more selective approach.

And this study reminds us that we shouldn’t think that we are prolonging patients’ lives by our early intervention.