When an arrhythmia causes the heart to beat too fast, the heart doesn't pump effectively. Specifically, there may not be enough time between heartbeats for the heart to fill with blood, causing blood to back up into the lungs.
The new non-steroidal and steroidal aromatase inhibitors are at least as effective as megestrol acetate (MA) as second-line hormonal agents in postmenopausal women with breast cancer.However, they are superior to MA in terms of tolerability and adverse effects.he Type I inhibitors have a steroidal structure similar to androgens and inactivate the enzyme irreversibly by blocking the substrate-binding site, and are therefore known as aromatase inactivators. Examples of such drugs include formestane and exemestane (Aromasin).
Aromatase is an enzyme that converts testosterone to estrogen. The supplements that block estrogen do not block estrogen production directly. Instead, these supplements block the aromatase enzyme. This action also boosts the production of testosterone naturally without the use of steroids. Novadex XT and 6-OXO are estrogen blockers that function by blocking the aromatase enzyme.