The CVP trace read against the ECG. Each cardiac cycle has an a wave (atrial contraction, after the P wave), a small c wave (tricuspid bulge at the start of systole), the x descent (atrial relaxation), a v wave (atrial filling against a closed valve, near the T wave), and the y descent (tricuspid opens). Load a pathology and read the waves — a giant fused cv wave in tricuspid regurgitation, absent a waves in AF, intermittent cannon a waves in AV dissociation, an M/W pattern in constriction.