Pacemaker: Difference between revisions

133 bytes added ,  28 January 2009
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* '''DDD''': the pacemaker records both the atrial and ventricular rate and can pace one of each chambers when needed.
* '''DDD''': the pacemaker records both the atrial and ventricular rate and can pace one of each chambers when needed.
* '''DDDR''': as above, but the pacemaker has a sensor that records a demand for higher cardiac output and can adjust the heart rate accordingly.
* '''DDDR''': as above, but the pacemaker has a sensor that records a demand for higher cardiac output and can adjust the heart rate accordingly.
* Biventricular pacemakers ('''CRT-P'''): leads in both ventricles are present to synchronize contraction. The lead pacing the left ventricle is usually positioned in the sinus coronarius. This cardiac synchronization therapy can improve symptoms and survival in some heart failure patients. Echo-optimizing might be helpful in finding the most effective pacingdelay between left and right ventricle.
* Biventricular pacemakers ('''CRT-P'''): leads in both ventricles are present to synchronize contraction. The lead pacing the left ventricle is usually positioned in the coronary sinus. This cardiac resynchronization therapy can improve symptoms and survival in some heart failure patients. Several optimizing methods are being evaluated to find the most effective pacing delay between left and right ventricle, they include echocardiography, narrowest QRS finding and invasive hemodynamic measurements with pressure and flow wires.
* '''[[ICD]]''' (Internal Cardioversion Device): this device can detect and treat [[Ventricular Tachycardia]] and [[Ventricular Fibrillation]]. ICDs are a seperate category and usually not put in the pacemaker category, although they do have a pacing function. Usually the first treatment is anti-tachy pacing (pacing at a rate +- 10% above the ventricular rate in ventricular tachycardia, which can convert the rhythm to sinus rhythm). If this is not effective an defibrillator shock is delivered, usually with 16-36 Joules of energy. ICDs can save lives in patients who have a high risk of ventricular arrhythmias. All ICDs have optional pacemaker activity to treat bradycardias. New biventricular ICDs have 3 leads: an atrial lead, a left ventricular lead and a right ventricular lead.
* '''[[ICD]]''' (Internal Cardioversion Device): this device can detect and treat [[Ventricular Tachycardia]] and [[Ventricular Fibrillation]]. ICDs are a seperate category and usually not put in the pacemaker category, although they do have a pacing function. Usually the first treatment is anti-tachy pacing (pacing at a rate +- 10% above the ventricular rate in ventricular tachycardia, which can convert the rhythm to sinus rhythm). If this is not effective an defibrillator shock is delivered, usually with 16-36 Joules of energy. ICDs can save lives in patients who have a high risk of ventricular arrhythmias. All ICDs have optional pacemaker activity to treat bradycardias. New biventricular ICDs have 3 leads: an atrial lead, a left ventricular lead and a right ventricular lead.
* Biventricular ICDs ('''CRT-D'''): an ICD with biventricular pacing option.
* Biventricular ICDs ('''CRT-D'''): an ICD with biventricular pacing option.