Rockroses for Northwest Gardens. Cistus x aguilarii âMaculatusâ. . . . rock roses are a pleasure to plant and their possibilities are endless. They are best clothing hot, dry banks, or tumbling over rocks in a chaparral-type planting, or billowing out from an island planting of drought resistant shrubs . . .
Premature Ventricular Contractions. Description. Premature ventricular contractions (PVCs) are beats which are initiated in the ventricles or lower chambers of the heart, prematurely. As opposed to PACs, when the SA node (the natural pacemaker of the heart) gets interrupted, PVCs do not interrupt the SA node.
Premature Ventricular Contractions. A premature ventricular contraction (PVC) occurs when a focus in the ventricle generates an action potential before the next scheduled SA nodal action potential. There are four main characteristics of premature ventricular contractions (PVCs): They are premature.