Abnormalities of cardiac rhythm represent one of the most frequent problem in clinical cardiology. They are occasionally life threatening, and can cause disabling symptoms, but today are often amenable to highly effective treatment measures with either drugs, interventions (surgical or catheter based) or device implantation (pacemaker, defibrillator). The Electrophysiology Laboratory at La Tour relies on state-of-the-art techniques for:
1. Non-invasive evaluation (Holter monitoring, stress testing, high amplification electrocardiogram, analysis of sinus variability and QT interval);
2. Invasive techniques (electrophysiological studies, radiofrequency ablation, pacemaker implantation, use of internal automated defibrillators and surgery).
Abnormalities of cardiac rhythm can appear at all ages and can either accompany other heart disease, or occur with an otherwise healthy heart. The severity of an arrhythmia mainly depends on a combination of the underlying heart disease and the hemodynamic consequences that are induced (palpitations, chest pain, shortness of breath, loss of consciousness, or even sudden death).
When a bradycardia (slowing of heart rhythm) is observed, an abnormal generation or transmission of the electrical impulse within the heart must be investigated. When such problems are sufficiently important and/or induce disabling symptoms, they can be corrected by the implantation of a permanent pacemaker. Also, recent advances in this field have broadened the use of pacemaker systems to help prevent certain types of rapid arrhythmias (atrial tachy-arrhythmia), as well as treat some of the patients suffering from severe cardiac failure.
Paroxysmal supraventricular tachycardias consist in sudden accelerations of the heart rate inducing palpitations, malaise and occasionally even loss of consciousness. The great majority of such tachycardias is related to either abnormal conduction pathways or abnormal foci in the heart muscle that develop an autonomous electrical activity. Both these
abnormalities can generally be selectively neutralised by using an electric current applied through a catheter (radio frequency ablation). Such a procedure lasts for one to two hours, and can be done through the skin using only catheters and local anaesthesia. The hospital stay typically lasts for 24 hours, and some of the less complex interventions can even be done within less than 12 hours. Success rates for most ablation procedures are in the range of 95-97% with a very low complication rate (ca. 1%). A great number of arrhythmias can be approached in this manner (atrial tachyca rdias, junctional tachycardias, accessory pathways, atrial flutter, and atrial fibrillation).
Ventricular tachycardias are in general associated with a major degree of heart muscle dysfunction, are more threatening, and can be associated with episodes of loss of consciousness or sudden death. They are one of the most dangerous late complications of large heart attacks. Although certain drugs can help in this situation, the best treatment at present consists in the implantation of an automatic defibrillator. This is a metallic box, very similar to a pacemaker that can be implanted under the skin, with leads connecting it to the heart. It is then capable of detecting major rhythm disturbances, so as to deliver a short electric shock to the heart to restore normal regular rhythm. Implantation of such a system requires a hospital stay of 24-48 hours.
Last modified on December 15th, 2015.
Unless specified otherwise, this text has been written by the editorial team.