Located in southeastern New Mexico, Carlsbad Caverns lie beneath the Earth's surface and were formed when limestone was dissolved by sulfuric acid during the last ice age.
There are three types of rate control medications: Beta Blockers, which slow the heart rate and relax the blood vessels. Examples include Atenolol (TenorminÂ®), Carvedilol (Coregâ¢), Metoprolol (Toprol XLâ¢, LopressorÂ®), and Sotalol (BetapaceÂ®)
1 Digitalis medicines control irregular heart rhythms (called arrhythmias) by slowing the signals that start in the sinoatrial (SA) node. 2  This, in turn, reduces the number of signals that travel through the atrioventricular (AV node). 3  Fewer signals mean fewer arrhythmias.