Cardiac Re-synchronisation Therapy

So we'll now talk about what we call cardiac resynchronization therapy pacemakers or sometimes more commonly as biventricular pacemakers. So these are specific pacemakers that are put into patients with heart failure. So patients who've had previous heart attacks or patients who've had, who has disease of the heart muscle itself that doesn't allow the heart pump to function to be effective. And in a certain subgroup of these patients, and I wish to emphasize the point that in only certain subgroup of patients with heart failure, this special pacemaker, what we call a CRTP for short, or a biventricular pacemaker can help improve the heart pump function to make it beat more efficiently, and that usually translates into patients feeling better, so you get less breathless and there are also studies that showed that on top of feeling breathless, less breathless, you actually live longer when you get these devices. So again, these devices are put in very much the same as your standard pacemakers as I alluded to before usually have one or two leads but this special pacemakers have three leads. So one of the leads goes into the top chamber of the heart, one goes to the bottom chamber of the heart and actually the third lead goes to the bottom left chamber of the heart and this is all put in again very similarly from the vein close to the shoulder and this third lead where it's placed actually sits on the outside of the bottom left chamber and to put this lead in is a lot more technically difficult compared to someone having a single or the dual chamber pacemaker because it involves the lead getting into what we call a specific bit of the heart called the coronary sinus which is essentially the vein that drains blood into the heart and the lead goes into the coronary sinus allowing this lead to sit on the outside of the heart. So that's the technically difficult bit of the procedure. But again, most of these procedures take approximately about an hour and a half to three hours long depending on how easy it is for us to get into the vein and also depending on whether there are veins that are supplying the outside of the heart where we can get the lead into. The additional complication of this procedure is that when we do this procedure, we normally give a dye so that we can visualize this vein that sits outside the heart and the dye contains iodine and you might get an allergic reaction to it and sometimes this dye can interact with the kidney function and hence if you do have pre-existing kidney disease we normally like to monitor the kidney function over the next 48 hours to make sure that it hasn't deteriorated with this die. Apart from that the complications are very much identical to putting in a pacemaker. There are occasions where you can damage this vein that sits outside the heart and on the rare occasion fluid can accumulate around the heart and almost always this fluid doesn't actually cause any problem at all. So it's all a matter of just watching and monitoring rather than actually needing to do anything active like putting a drain in the sac where the heart sits to get rid of that fluid to relieve the pressure and most of the time this settles it down conservatively.