The key difference between PAC and PVC is that PAC is a type of premature electrical activation originating in the upper chambers of the heart, while PVC is a type of premature electrical activation originating in the lower chambers of the heart.
An arrhythmia is an irregular heartbeat or heart rhythm, meaning that the heart is out of its usual normal rhythm. There are different types of irregular heart rhythms, such as premature atrial contraction (PAC), premature ventricular contraction (PVC), atrial fibrillation (Afib), atrial flutter, paroxysmal supraventricular tachycardia (PSVT), accessory pathway tachycardia, AV nodal reentrant tachycardia (AVNRT), and long QT syndrome.
CONTENTS
1. Overview and Key Difference
2. What is PAC
3. What is PVC
4. Similarities – PAC and PVC
5. PAC vs PVC in Tabular Form
6. Summary – PAC vs PVC
What is PAC?
Premature atrial contraction (PAC) is a type of irregular heart rhythm. It is a condition that occurs due to premature electrical activation originating in the heart’s upper chambers. It can also be defined as extra heartbeats that start in the upper chambers of the heart. The causes for PAC are a flop in the amount of blood going to the heart, heart injury, hypertrophic cardiomyopathy, and a problem with the amount of electrolytes or minerals in the body. The risk factors for this condition include older age, being taller, having cardiovascular disease, not exercising, high HDL cholesterol, higher systolic blood pressure, not drinking enough water, excessive caffeine intake, not having adequate sleep, anxiety, and electrolyte imbalance. The symptoms of this condition may include heartbeats having a lot of force, heartbeats that skip, heartbeats that pound (palpitation), anxiety, and shortness of breath.
Figure 01: PAC
PAC can be diagnosed through physical examination, electrocardiogram (EKG), temporary heart monitor, and echocardiogram. If you are suffering from occasional PAC, there is no need for treatment. However, if it does not go away, it can be treated through medication (such as beta blockers) and catheter ablation.
What is PVC?
Premature ventricular contraction (PVC) is a type of irregular heart rhythm, and it causes extra heartbeats that start in the lower chambers of the heart. Moreover, PVC can be caused by electrolyte imbalances, myocardial infarction, heart failure, high adrenaline, and reduced blood flow to the heart. The risk factors for PVC include heart failure, high blood pressure (hypertension), a history of heart attacks, and structural problems in the heart, such as hypertrophic cardiomyopathy. The symptoms of this condition may include dizziness, fainting feeling, heart palpitation, pounding sensation in the heart, and shortness of breath.
Figure 02: PVC
PVC can be diagnosed through physical examination, electrocardiogram (EKG), wearing a Holter monitor, blood test, cardiac stress testing, cardiac MRI or CT scan, coronary angiograms, echocardiograms, and electrophysiology studies. Furthermore, there is no need for treatment for infrequent PVC. However, if it is frequent, it can be treated through medications like antiarrhythmics to decrease irregular heart rhythms or beta-blockers and calcium channel blockers to lower blood pressure and catheter ablation.
What are the Similarities Between PAC and PVC?
- PAC and PVC are two different types of irregular heart rhythms.
- Both conditions cause extra heartbeats in heart chambers.
- Both conditions may have similar symptoms, such as heart palpitation, shortness of breath, etc.
- Both conditions can be diagnosed through physical examination and electrocardiogram (ECG or EKG)
- They can be treated through specific medications and catheter ablation.
What is the Difference Between PAC and PVC?
PAC is a condition of premature electrical activation originating in the upper chambers of the heart, while PVC is a condition of premature electrical activation originating in the two lower chambers of the heart. Thus, this is the key difference between PAC and PVC. Furthermore, PAC can be caused due to decreased levels of blood going to the heart, injury to the heart, hypertrophic cardiomyopathy, and a problem with the body’s electrolytes or minerals amounts. On the other hand, PVC can be caused by electrolyte imbalances, myocardial infarction, heart failure, high adrenaline, and reduced blood flow to the heart.
The below infographic presents the differences between PAC and PVC in tabular form for side-by-side comparison.
Summary – PAC vs PVC
PAC and PVC are two different types of irregular heartbeats or rhythms. They are also known as arrhythmias. Both conditions may have similar symptoms, such as heart palpitation, shortness of breath, etc. PAC is a condition that originates in the upper chambers of the heart, while PVC is a condition that originates in the two lower chambers of the heart. So, this summarizes the difference between PAC and PVC.
Reference:
1. “Premature Atrial Contractions: Causes, Symptoms, Diagnosis, Treatment.” WebMD.
2. “Premature Ventricular Contractions (PVCS).” Cleveland Clinic.
Image Courtesy:
1. “NSR and Ectopic beats (PVC and PAC)” By YitzhakNat – Own work (CC BY-SA 4.0) via Commons Wikimedia
2. “PVC detection Using PGG” (CC BY-SA 3.0) via Commons Wikimedia