Studies now show that smoking is the major cause of heart attacks in people under 40 years of age. Read what this means - for younger smokers, and for those not so young - here.

Amiodarone is the most powerful antiarrhythmic drug ever developed - but it is also the most toxic. In this article I describe this unique drug - its benefits, the risks, and how it should be used, here.

As expected, this week the United States Food and Drug Administration (FDA) approved dronedarone (Multaq, Sanofi-Aventis) for the treatment of atrial fibrillation. Dronedarone is thought to be a safer alternative for atrial fibrillation than its close cousin, amiodarone. The approval of the new drug largely rested on the results of the ATHENA trial, which demonstrated a significant reduction in the composite endpoint of death or hospitalization when dronedarone was compared to placebo.

There are some lingering questions with dronedarone, however. In another clinical trial, patients with significant heart failure actually had significantly increased mortality when this drug was used.

Accordingly, the new FDA indication for dronedarone specifies that the drug should be avoided in patients with significant heart failure.

You can read more about dronedarone here.

Traditionally, cardiologists have thought of coronary artery disease (CAD) as discrete blockages in the coronary arteries (the arteries that supply blood to the heart muscle). The key to treating CAD, then, was to identify the specific location and significance of blockages (usually by cardiac catheterization), and to treat the significant ones with stents (or, if absolutely necessary, by referring to a surgeon for bypass surgery).

Gradually this conceptualization of CAD is changing. CAD is a chronic, progressive disease that needs to be identified and treated aggressively, even if no significant blockages are present. And most often, the best treatment is with medications and aggressive lifestyle changes. You can read about this new thinking on CAD here.