¿What is cardiac resynchronization therapy ?
It is a treatment for patients with advanced heart failure. It is indicated in patients with severe systolic dysfunction ( contractile force of the heart is greatly reduced ), dyspnea (difficulty breathing ) for moderate or small efforts and disorder in the intrinsic conduction system of the heart at the level of the ventricles ( manifested by wide QRS complex, usually left bundle branch block ).
These patients have a heart whose contractility is dire and also the different segments of the ventricles contract asynchronously, which reduces even more the efficiency of cardiac contraction. The TRC has shown improve heart function, quality of life and exercise capacity of patients, reduces hospitalizations and improves survival. With this treatment patients can live longer and better.
¿How it works ?
It is a cardiac stimulation device that has the ability to send an electrical stimulus in both ventricles, which gets improve lost sync in cardiac contraction of these patients. The pacemaker can be resincrozadores ( only avoids the slow rhythms ) or defibrillator ( besides avoiding slow rhythms may terminate malignant ventricular arrhythmias that can cause sudden death of the patient).
¿difference does a pacemaker defibrillator or conventional ?
The resynchronization have the ability to stimulate the left ventricle. Conventional devices can stimulate and sensing in one or two heart chambers ( atrium and the right ventricle ), but can stimulate cardiac resynchronization three cardiac chambers ( right atrium and both ventricles ), hence the name Three-chamber. The resynchronization has a third electrode that stimulates directly into the left ventricle. With this, it is achieved that the device simultaneously in both stimulated and accomplished syncing ventricles contractility both. That electrode implantation is usually done through the coronary sinus, which is a small vein surrounding the left ventricle the mitral annulus. That electrode implantation requires special tools and the doctor who performs it must know the specific technique.
¿Which patients can receive this therapy?
So 30 % of patients with advanced heart failure, have intraventricular conduction disturbances, which asynchrony normal ventricular contractility and this will impair cardiac function. It is in these patients is indicated where the TRC. The TRC is an adjunctive therapy to pharmacological treatment in patients with advanced heart failure, systolic dysfunction with electric and asynchrony. The electrical asynchrony is due to a disease specific system electrical conduction system at the ventricular level, manifested by a bundle branch block. The improvement is more evident in patients with left bundle branch block, but the TRC also may be indicated in patients with right bundle branch block. A subgroup of patients in whom this CRT is indicated in those patients dependent on a pacemaker and have a left ventricular systolic dysfunction.