Once the physician has recorded an arrhythmia and established its location in the heart, he or she can decide if treatment is necessary, and, if so, which treatment option is most appropriate.
When treating arrhythmias, physicians consider if an underlying heart problem such as heart disease, past heart attack, or valve disease is contributing to an arrhythmia. Physicians also evaluate conditions such as ischemia (lack of oxygen to the heart) or electrolyte or metabolic abnormalities, which may affect any underlying heart problem, and determine if the patient prefers drug therapy or other treatment approaches.
For purposes of treatment, physicians use two classifications of arrhythmias: ambient, or triggering, arrhythmias, and sustained arrhythmias.
Triggering arrhythmias include premature atrial contractions and premature ventricular complexes.
Sustained arrhythmias include:
- Atrial fibrillation (chaotic electrical activity in upper chambers of the heart),
- Supraventricular tachycardia (rapid heart rate),
- Ventricular fibrillation (in which the heart quivers rather than contracts--a medical emergency), and
- Ventricular tachycardia (an abnormally fast heartbeat that originates in the upper chambers of the heart).
The goals of antiarrhythmic treatment are to prevent or suppress arrhythmias by treating the underlying cause of arrhythmias. Physicians also seek to prevent conditions that contribute to arrhythmias, such as ischemia and metabolic imbalances in the heart muscle, and to manage serious symptoms such as lightheadedness, shortness of breath, fatigue, and chest pain.
When medical treatment is required to suppress an atrial arrhythmia, physicians decide which drugs to use based on the risks and quality-of-life effects of the arrhythmia, the presence of any underlying disease, the severity of a person’s symptoms, and the risk of side effects. Common medications include:
Antiarrhythmic agents - These drugs affect the electrical activity of the heart rate by slowing the conduction of nerve impulses through heart tissue or lengthening time between two connective beats. Certain antiarrhythmic agents are not used in people who have congestive heart failure.
Beta-blockers - Beta-blockers block the effect of adrenaline and are effective in slowing and regularizing the heart rate.
Calcium channel blockers - Calcium channel blockers prevent calcium atoms from penetrating heart muscle tissue. This forces muscles to contract less vigorously by making them less responsive to the electrical signals that cause muscle contraction. This action also dilates (widens) blood vessels and lowers blood pressure. Calcium channel blockers also slow conduction through the atrioventricular node, making them useful for certain types of arrhythmias.
Digitalis - Digitalis regulates the heart’s rate and rhythm by slowing the transmission of electrical impulses from the atria to the ventricles. The drug also strengthens the force of heart contractions, which can improve circulation.
Some antiarrhythmic medications may be harmful to patients who have an implanted pacemaker, or who had or are having surgery, including dental surgery. People should also be aware that caffeine can decrease the effectiveness of antiarrhythmic medications.
In some cases, such as with arrhythmias that cannot be treated with medication, physicians may use interventional or surgical procedures to control the arrhythmia. These procedures may include:
- Pacemaker Implantation – This small electronic device is surgically implanted under the skin near the collarbone. The pacemaker regulates a slow or erratic heartbeat by sending rhythmic electrical charges to the right atrium and right ventricle.
- Cardiac Defibrillation Implantation – For patients with life-threatening arrhythmias, this device constantly monitors the heart rate and, when it detects an irregularity, shocks the heart to normalize its rhythm.
- Radiofrequency Catheter Ablation – For this minimally invasive treatment, a catheter with an electrode tip is positioned on the affected area. The catheter delivers energy to strategically destroy tissue that is interfering with the normal transmission of electrical impulses through the heart.
- Maze Procedure – For this treatment, a physician makes multiple incisions through the atrium. The resulting scar tissue conducts impulses through the heart’s electrical system in a way that allows normal conduction but does not sustain atrial fibrillation. Since it is a form of cardiac surgery, it is reserved for those patients who are highly symptomatic.
