PVC's

More Research

The nursing staff at cardiac rehab again were concerned about my extra heart beats. As a mentioned earlier, as soon as you arrive at cardiac rehab, the staff places a monitor on you from start to finish. My PVC's were evident, but the concern is a run of the PVC's. The danger of the internet is learning too much, but the good thing is being able to discuss your problems with your physicians in a meaningful & knowledgeable manner.

The nursing staff will try to get me to see my cardiologist sooner than March 8th (my next scheduled appointment. As you read below in the article I found, this seems to be a concern when you have a run of PVC's and I did this at rehab. As stated in the article, "Ventricular tachycardia is a sustained run of rapid ventricular contractions." So, I'm again trying to not do anything stupid & wait till my next appointment. Of course the issues are 1 - the waiting game & 2 - what danger am I in when I am at home or doing things around the house?

What are the dangers of premature ventricular contractions?

Premature ventricular contractions in healthy individuals without high blood pressure and heart diseases do not pose any health risks. Premature ventricular contractions in patients with heart diseases (heart attacks, heart failure, diseases of the heart valves) may be associated with increased risks of developing ventricular tachycardia. Ventricular tachycardia is a sustained run of rapid ventricular contractions. Ventricular tachycardia is life-threatening because: 1) it occurs suddenly with no prior warning, and 2) it frequently develops into ventricular fibrillation. Ventricular fibrillation is a chaotic rhythm where the ventricles quiver rapidly in a purposeless fashion. The heart with ventricular fibrillation cannot pump blood effectively to the brain and the rest of the body. If untreated, ventricular fibrillation can be fatal within minutes. An estimated 250,000 Americans die in this way each year.

Many doctors believe that premature ventricular contractions do not necessarily cause ventricular tachycardias or ventricular fibrillations. Instead, premature ventricular contractions may be merely indicators (symptoms) of serious heart diseases or other serious conditions such as hypokalemia, hypoxia, and on-going heart damage from heart attacks, or medications such as digoxin and aminophylline toxicity. It must be emphasized that many premature ventricular contractions are harmless (benign) and not associated with structural heart disease. If the work up for underlying heart disease is unrevealing, the patient can be assured that their prognosis is excellent.

How is premature ventricular contraction diagnosed?

Electrocardiogram (EKG, ECG)

An electrocardiogram (EKG, ECG) is a brief recording of the heart's electrical discharges.

Holter monitor

A standard EKG and a rhythm strip performed at the time of a visit to the doctor's office may not detect the premature ventricular contractions because they may not be occurring at that moment. Holter monitoring is then necessary to detect the premature ventricular contractions in these patients with heart palpitations. A Holter monitor is a continuous recording of the heart's rhythm for 24 hours.

Echocardiography

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.

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 three 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 increase in premature ventricular contractions and development of ventricular tachycardias.

Adjuncts to ECST (stress echo and nuclear imaging)

Another supplement to the routine ECST is stress echocardiography. During stress echocardiography, the sound waves of ultrasound are used to produce images of the heart at rest and at the peak of exercise.

Blood tests in diagnosing causes of premature ventricular contractions

Blood tests for diagnosing conditions that can cause premature ventricular contractions include:

• blood electrolyte levels can be performed to detect low potassium or magnesium levels (hypokalemia and hypomagnesemia);
  
  
• blood drug levels can be performed to detect digoxin and aminophylline drug toxicity or thyroid levels, for example, an overactive thyroid may result in premature ventricular contractions;
  
  
• blood oxygenation (oximetry) can be measured to detect hypoxia;
  
  
• blood tests can be performed to detect illicit drugs, such as amphetamine abuse; and
  
  
• blood levels of cardiac enzymes [creatine phosphokinase (CPK), troponins (regulatory proteins)] can be performed to assess for heart muscle damage as a result of heart attacks.