Electrocardiogram

An electrocardiogram (ECG) may be performed to detect obvious problems, although your physician will only do so if it is felt that it will yield important data. The ECG allows the doctor to look at the electrical activity that occurs every time your heart beats. It precisely measures the heart signals looking at 12 different views of the heart muscle, studying the conductive pattern in particular.

But as precise as it is, the ECG can only analyze the condition of the heart during the time you are lying on the table with the electrodes attached. It cannot predict whether your heart may perform erratically after the electrodes are removed and you go home.

Cardiac arrhythmias are "irregularities" in the heartbeat. Sometimes you can feel them and sometimes you can't. Some are not serious and will not be treated, while your physician may choose to treat others, either with prescription drugs, a pacemaker or an implantable defibrillator.

Holter Monitor

If you are having frequent symptoms (like dizziness or heart fluttering), or your doctor suspects that non-symptomatic arrhythmias may be occurring, the doctor may choose to perform a Holter. This is a small recorder that is worn for a 24- or 48-hour period that records your heart activity.

When you return after 24/48 hours, the tape is scanned on a special machine while a technician looks for any changes in heartbeat occurring over that 24/48 hour period, whether you felt them or not.

While the Holter may show other cardiac arrhythmias associated with your heart, it can only record data during the 24 or 48 hour period it is connected to you with electrodes. Sometimes your doctor will be satisfied with the results and not feel that a longer-term monitor is necessary. But at other times the physician may suspect an arrhythmia that can only be caught by a memory loop recorder and thus will want you to wear one to catch the intermittent problem. Sometimes both procedures will be ordered.