Introduction: Physiological pacing is a new and innovative technique of activating the heart’s native conduction system via a pacing lead situated at the His bundle or left bundle branch first reported by Deshmukh et al. (2000). The technique was developed as an alternative to right ventricular pacing, which is known to cause ventricular dyssynchrony (Figure 1).
Aim: 1. To assess the procedure time, fluoroscopy time and complication rates of physiological pacing procedures and compare the data with traditional established methods (dual chamber pacing [DDD], cardiac resynchronization therapy [CRT], implantable cardioverter-defibrillator [ICD]); 2. to determine whether there is any relationship between device type, procedure time, fluoroscopy time and complication rates.
Method: Patients were categorised into device group: DDD pacemaker (n=458), conduction system pacing (n=174), CRT (n=148), ICD (n=153). Fluoroscopy time, procedure time and documented complications were extracted from the central database for each device group.
Results: Upon analysis of the statistical outputs, the procedure time (minutes) for physiological pacing (CSP) and CRT procedures were significantly longer (p=0.05). The fluoroscopy time (minutes) for physiological pacing and CRT procedures were significantly longer than those of DDD and ICD procedures (p<0.001). There was no significant difference in fluoroscopy time between DDD and ICD procedures. However, physiological pacing procedures were found to have significantly lower fluoroscopy times than CRT procedures (p=0.002). There was no significant effect of time for any of the device groups. The DDD group displayed the highest complication rate of 4% over the 4 years with a total of 20 complications and one procedure-related death. CRT and ICD groups displayed a complication rate of 1.4% and 1.3%, with a total of 3 and 2 reported complications, respectively. Physiological pacing procedures displayed the lowest complication rate of 0.5%, with only 1 complication over the 4-year period
Discussion: The extended procedure and fluoroscopy time of physiological and CRT procedures are supported by Keene et al. (2019) and can be attributed to the smaller target area of the His bundle/left bundle branch and technically demanding navigation of the coronary venous system, respectively. Additionally, the techniques displayed have been well established from the initial set up of the service in 2017, and the operating procedures have been optimised; therefore, there was no significant effect on time. The complication rates can be attributed to the experience of the operator, the comorbidities of the patients and the urgency of the procedure. Physiological pacing, CRT and ICD procedures are exclusively performed by experienced operators with a high annual procedure volume (>50 per annum) supported by two experienced specialist cardiac physiologists, whereas DDD devices are occasionally implanted by specialist registrars learning the procedure under supervision with lower annual procedure volumes (<50 per annum) supported by non-pacing-accredited cardiac physiologists (Kirkfeldt et al., 2014). ❑