The precise shape of the QRS can give an indication as to where precisely in the heart muscle the abnormal electrical activity arises. If someone has PVCs that all have the same appearance, they are considered "monofocal", if PVC’s have different appearance, they are considerevole “multifocal”. Treatment
Isolated PVCs with benign characteristics and no underlying heart disease require no treatment, especially if there are limited symptoms.The most effective treatment is the elimination of triggers (particularly stopping the use of substances such as caffeine and certain drugs, like tobacco). If frequent, it’s possible to use:

Medications
Antiarrhythmics: these agents alter the electrophysiologic mechanisms responsible for PVCs. In CAST study of survivors of myocardial infarction encainide and flecainide, it was shown that, though those drugs could suppress PVC, they also increased the risk of death. However, while moricizine increased the death rate when used with diuretics, it reduced the frequency of deaths when it was used alone. Beta blockers: do not directly affect or reduce the occurrence of PVCs, but reduce cardiac contractility which makes PVCs less obvious to a person; possibly reduce catecholamine induced PVCs (in catecholamine-sensitive people) due to adrenaline not reaching sinus node as much. Calcium channel blockers
Electrolytes replacement
Magnesium supplements (e.g. magnesium citrate, orotate, Maalox, etc.) Potassium supplements (e.g. chloride potassium with citrate ion)
Radiofrequency catheter ablation treatment. It is advised for people with ventricular dysfunction and/or tachyarrythmia or very frequent PVC (>20% in 24 h) and normal ventricular function.
These differences may be due to rates of high blood pressure and atherosclerosis, which are more easy to find in older persons. In 101 people free of heart disease during 24 hours Holter monitoring, 39 had at least 1 PVC, and 4 at least 100. Heart disease was excluded after physical examination, chest x-ray, ECG, echocardiography, maximal exercise stress test, right- and left-heart catheterization and coronary angiography. In 122,043 United States Air Force flyers and cadet applicants during approximately 48 seconds of ECG 0.78% (952 males) had PVC within all age groups, but with increased incidence with increasing age. Ventricular ectopy is more prevalent in men than in women of the same age data from large, population-based studies indicate that the prevalence is less for young white women without heart disease and greater for older African American individuals with hypertension. References
Further reading


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