Although rare, infection of a pacemaker or a defibrillator is an important complication which must and can be treated effectively. Cardiac electronic implantable device (CIED) infection is a Class I indication for extraction but recent data has demonstrated that less than 2 in 10 patients receive appropriate treatment. Prof Carina Blomström-Lundqvist, Swedish Professor of Cardiology, and Dr Archie Rao, British consultant cardiologist, are both passionate about this topic. Carina Blomström-Lundqvist is the lead author of the European CIED infection guidelines and Archie Rao has led a gap analysis into the knowledge of CIED infection and treatment. They explain how to recognise a patient at risk and what to do to provide best outcomes for your patient.
This series is supported by Philips.
- Thank you so much Carina.
- So we are discussing device infections. Now what should I be looking for?
- So I think it's good practise to have a standard way of examining these patients. Classically, we've always suggested that one look can examine the device site itself. So visual inspection of the site, an inquiry about how the patient feels, and of course a specific ask if the patient has had antibiotic therapy or fevers or infection, wherever that might have come from, especially if they've had more than one episode and have required more antibiotics. That's the basic minimum for evaluation of a CIED patient.
- Yeah, so what are the types of device infection? So for example, so for the infection localised to the pocket area, what is the difference between a superficial infection and a pocket infection? So I think this is really an important distinction, Carina. So there is a device site infection, but that can be, perioperatively it can be a superficial infection. And the key difference between a superficial infection and a generator pocket site infection is that the superficial incisional infection only involves the skin and the subcutaneous tissue and does not communicate with the generator pocket at all. Now it is really important that making that distinction is difficult and it's very much a diagnosis of exclusion. So you treat it, if you're suspecting a superficial infection, you treat it with antibiotics, oral antibiotics, but you ensure that you review that patient to make sure that that infection has healed. We then move on to the next, which is a pocket infection. And a pocket infection or a generator site infection is one that involves the pocket and the generator. Oftentimes this presents with pain around the site. You can often have redness, inflammation, swelling, tenderness. These are the common signs, but less commonly it can just present with defamation of the pocket. The pocket just doesn't look right, the generator is threatening to erode, or there is pre-erosion around the area, or there might be something as minimal as slight tethering of skin. So the index of suspicion is pretty important. And finally, you come to the most dreaded of them all, systemic infection.
- It's harder to recognise, isn't it? Could you please elaborate on the symptoms and the clinical signs to watch out for?
- Absolutely, and I think the difficulty with systemic infection is that patients can present at a time remote to an intervention. So making that association between a systemic infection that might present as a fever of unknown origin, recurrent antibiotics for generally non-specific illness with actually the presence of a CIED is pretty key. And once again, making that link between the fact that the patient has an infection or a systemic bacteremia with the fact that the patient has an indwelling cardiac device in situ is really important.
- Hmm, so what is the right course of treatment if I recognise such patient in front of me. Which next steps should I take? Which are the mandatory diagnostic tools to be used? And a last question regarding this is full system extraction always needed?
- So it's a really important question Carina. And if I may just start with first of all making the distinction between superficial and pocket infection. We've already talked about the only type of infection that can potentially be managed with just antibiotics is superficial incisional infection. Every other type of CIED infection mandates not just periods, long periods of intravenous antibiotic therapy, but a full system extraction. Now, in order to make the right diagnosis one has to start off with blood cultures preferably three sets of blood cultures at least 30 minutes apart, taken in a sterile manner so you can actually identify the right organism and institute the right antibiotic therapy. We then move on to cardiac imaging, mainly echocardiography preferably transesophageal echocardiography very much to understand the extent of involvement of the infection, because this will decide if it's just a generator infection or it's extended down to the leads or the valves or indeed even extravascular seeding. And this will decide the duration of intravenous antibiotic therapy. The final and definitive management, of course of all cardiac device infection is a full system extraction with every attempt made to take out all hardware at all times.
- Yeah, and I think it's important to emphasise that a superficial infection is not actually a device infection as opposed to a pocket infection.
- Just to make that clear. So that is very clear. When suspected CIED infection the patient should be referred to a colleague expert. However, I often see device infection patients who have received repeated antibiotics in my practice and a device infection should be recognised and treated early. So why is that and what is meant by early?
- So you bring a really important point in question and it's getting that diagnosis right. It's that suspicion of CIED infection which is often overlooked because the general feeling is, oh, the patient has a fever let's start antibiotics, let's see how they go. This in fact impacts on very poor outcomes for these patients because there is evidence, emerging evidence and published evidence that the sooner we extract the hardware the better the patient outcomes are and sooner is as early as three days and as late as six days. So as quickly as is feasible, but between at least within a week, if we can extract all hardware and continue intravenous antibiotics, appropriate intravenous antibiotics. That gives the best chance for the patient of eradicating that infection.
- Hmm, true. So typically colleagues tend to worry about infections early after an implantation and they link it to the procedure of the implantation. Can you elaborate a little bit on this mindset and what the consequences can be? So when can a patient get infected?
- So this is hard, isn't it? In the real world, making that association between an existing cardiac device and infection is very much one of understanding the concept that when you have a systemic bacteremia, seeding of bacteremia, it can seed onto metal indwelling in the body and it doesn't have to be related to the procedure itself. And so it can be remote from the time of implant, or indeed remote from any intervention around the pocket site. So commonly what I've seen is that if you have a pocket intervention and this is related to the intervention, the infection, the generator infection, or the pocket infection presents in the 30 day period around the intervention. But apart from that, aside from that systemic infection may have absolutely nothing to do with intervention on the pocket at all. So this is systemic seeding of the bacteremia that's been around. It could be from a dental abscess, it could be from an indwelling catheter, it could be from anywhere. But because there's hardware in the body it goes and deposits itself there.
- So thank you very much Dr Rao for the discussion and insights on how to recognise device infection in a patient and also how to treat them effectively. I think to identify all types of CIED infections it's important to remember that the patient has a device in the first place. Signs could be warmth, red pocket, fever, sweating, or repeated infections. Device infection is a class one indication for a complete system removal and it should be extracted timely. Now, if extraction is the optimal treatment what is the reason why antibiotics alone fail? This will be covered in our next podcast so please listen to the podcast or go to the website. Thank you for listening and thank you Dr Rao.
- Thank you.