Premature Ventricular Contractions (PVCs)
View Table of Contents
- What are premature ventricular contractions (PVCs)?
- What happens during a premature ventricular contraction?
- How common are premature ventricular contractions?
- What causes premature ventricular contractions?
- What are premature ventricular contraction symptoms?
- What are the dangers of premature ventricular contractions?
- How is premature ventricular contraction diagnosed?
- How is premature ventricular contraction diagnosed? (Part 2)
- How is premature ventricular contraction diagnosed? (Part 3)
- What are the treatments for premature ventricular contractions?
- What are the treatments for premature ventricular contractions? (continued)
How is premature ventricular contraction diagnosed? (Part 2)
Echocardiography uses ultrasound waves to produce images of the heart's chambers and valves and the lining around the heart (pericardium). Echocardiography is useful in measuring the size of the heart chambers, the forcefulness of heart ventricle contractions, the thickness of the heart muscles, and the functioning of the heart valves. Echocardiography is therefore useful in diagnosing conditions that can cause premature ventricular contractions such as:
- Mitral valve prolapse: Echocardiography can detect and measure the severity of mitral valve prolapse and other valvular diseases.
- Muscle hypertrophy: Echocardiography can detect heart muscle hypertrophy (thickening of heart muscle) as a result of long-term high blood pressure.
- Heart muscle damage: Echocardiography can measure the extent of heart muscle damage from heart attacks or cardiomyopathy.
- Ejection fraction: Echocardiography can be used to calculate the ejection fraction of the left ventricle. Ejection fraction is a measure (estimate) of the amount of blood pumped during each contraction of the ventricle. Heart ventricles extensively weakened by heart attacks or cardiomyopathy will have low ejection fractions. Patients with low ejection fractions have higher risks of developing life-threatening ventricular tachycardias and fibrillations than patients with normal ejection fractions.
Exercise cardiac stress test (treadmill stress test)
Exercise cardiac stress testing (ECST) is the most widely used cardiac stress test. The patient exercises on a treadmill according to a standardized protocol with progressive increases in the speed and elevation of the treadmill (typically changing at 3-minute intervals). During the ECST, the patient's electrocardiogram (EKG), heart rate, heart rhythm, and blood pressure are continuously monitored. If a coronary arterial blockage results in decreased blood flow to a part of the heart during exercise, certain changes may be observed in the EKG, including increases in premature ventricular contractions and development of ventricular tachycardias.