Figure 30-10 Ventricular bigeminy.
© Jones & Bartlett Learning.
When a PVC occurs every second complex, it is known as ventricular bigeminy (Figure 30-10). When a PVC occurs every third complex, it is known as ventricular trigeminy (Figure 30-11). Likewise, a PVC occurring every fourth complex is considered ventricular quadrigeminy (Figure 30-12). The word “ventricular” is present to designate the ectopic complexes as ventricular in origin (remember, you can also have supraventricular bigeminy, etc.).
Figure 30-10 Ventricular bigeminy.
© Jones & Bartlett Learning.
Figure 30-11 Ventricular trigeminy.
© Jones & Bartlett Learning.
Figure 30-12 Ventricular quadrigeminy.
© Jones & Bartlett Learning.
Usually, the most commonly found PVCs are unifocal and have the same coupling intervals and morphologic appearance. Multifocal PVCs are less commonly found, have different morphologic appearances, and typically do not appear with any recurring coupling interval.
Clinically, these rhythm abnormalities are stable and are not cause for alarm. The exception to this rule, however, occurs when the PVCs do not cause an adequate mechanical contraction. In these patients, the cardiac output can be dramatically altered due to the presence of the PVCs, and clinical management and eradication of the premature complexes are indicated emergently. A good clinical habit to develop is to take the patient’s pulse whenever you see a patient with bigeminy. If the palpable pulse is half of the pulse that you see on the monitor or the rhythm strip, you need to take action to eradicate the cause of the PVCs or to directly treat them. Don’t forget to check the other vital signs as well!