PVC and PAC (Palpitations)
One of the most common complaints cardiologists are asked to evaluate are palpitations. Palpitations is a term most patients apply to a sense of an irregular heartbeat. Although this can vary greatly between individuals, one of the most common descriptions that patients give is of “skipped beats.” In most cases, an investigation will determine if these symptoms are due to “extra heartbeats” which are termed premature ventricular contractions (PVC) and premature atrial contractions (PAC) depending on where the extra heartbeat originates from. PVCs have their focus of origin in the ventricles, or pumping chambers of the heart, and PACs have their focus of origin in the atria, or upper chambers of the heart. Each of these can cause similar symptoms. The difference can be determined with a monitor or EKG. These arrhythmias are common and are often discovered in patients that have no symptoms.
Causes of PVCs and PACs
The causes of PVCs and PACs vary. They are more common in patients with other underlying cardiac disease including coronary artery disease or a history of heart attack. There is an increased likelihood of these being experienced in patients with valvular heart disease such as mitral valve prolapse. There are other medical conditions that can be associated with these such as an overactive thyroid or changes in blood chemistry such as potassium.
Your physician will undertake an investigation to determine whether there is a specific cause. The degree of seriousness of the arrhythmias varies greatly between individuals and is usually dependent on any potential underlying cause and the degree of arrhythmia. In some cases, although rarely, these arrhythmias can lead to other arrhythmias, some of which can be more serious and persistent. Examples of these include atrial fibrillation and ventricular tachycardia. In many cases, however, no specific “cause” of these is determined, in which case they are often termed “benign” PVCs and PACs. This usually indicates a very low likelihood that the arrhythmia is associated with any other significant cardiac disease, or that it is likely to lead to any other significant cardiac condition such as a heart attack.
Diagnosing PVCs and PACs
Initially, a careful history and examination will be done to search for clues as to the cause of these arrhythmias. A series of tests will likely be ordered by your physician, which may include a Holter monitor or event monitor that you wear to record the extent of your arrhythmia. You may also be asked to get an echocardiogram to look for other conditions of the heart such as valve disease and evidence of coronary artery disease. Many patients are asked to undergo some type of stress testing to evaluate for coronary artery disease. Sometimes blood test may be ordered to check your electrolytes or thyroid, for instance.
Symptoms of PVCs and PACs
How patients experience PVCs and PACs can vary greatly. In many cases these are simply isolated symptoms that occur without a specific pattern. They can occur rarely or frequently and sometimes feel as though they are occurring consecutively. Patients generally tend to notice them more when they are at rest, and often complain that they notice them mostly when they are resting in bed getting ready for sleep. In rare cases these can be quite severe, frequently recurrent, and can lead to other arrhythmias of the heart, although usually they remain an isolated problem.
Treatment of PVCs and PACs
The treatment for PVCs and PACs depends on the cause. In many cases all that is required are lifestyle changes such as the avoidance of stimulants such as caffeine containing products or over-the-counter decongestants. Many individuals notice a marked improvement with stress management and other lifestyle changes such as an exercise program and adequate rest. Medications, if necessary, are usually simple, well tolerated and effective. If a significant underlying condition is determined to be the cause, then the treatment will usually be directed at correcting the underlying condition such as thyroid disease or addressing coronary artery disease if present, as a few examples. In most patients, however, the condition is determined to pose little risk for a more serious heart problem and patients are satisfied with reassurance. If this is the case, there should be no effect on one’s ability to live.