Good chronotropic competence
75-year-old woman implanted with an Adapta pacemaker for complete atrioventricular block post-aortic valve surgery; routine control 3 months after implantation; asymptomatic.
- programming in AAIÛDDD mode without rate response;
- quasi-permanent ventricular pacing; limited percentage of atrial pacing; this pacemaker-dependent patient presents late PVCs potentially explaining the 1.1% of AS-VS;
- atrial histogram showing a quasi-permanent atrial spontaneous rhythm and a satisfactory rate distribution;
- the ventricles are paced; the ventricular rate curve is modeled on that of the atrial rate.
As in the previous report, this first page is used to verify that the system is functioning properly (no signs of wear, proper functioning of the 2 leads; the sensing could not be tested, patient appearing pacemaker-dependent). This patient is also programmed in AAIxDDD mode. The histograms, on the other hand, are reversed:
- the ventricles are paced in a quasi-permanent manner, with the percentages of ventricular pacing approaching 100%. This result is not surprising given that aortic valve surgery is commonly associated with a permanent lesion of the atrioventricular conduction pathways. The programming of the AAIxDDD mode must therefore be rediscussed. Every 16 hours, the device searches for the presence of an AV conduction, which results in a single deficient beat but that can probably be avoided by reprogramming the patient in DDD mode;
- the distribution of the atrial rates is quite satisfactory with obviously a preserved chronotropic function. There is therefore no reason to program the rate response in this patient and it is necessary to maintain an acceleration solely based on the acceleration of the sinus rhythm, i.e. the most physiological and best reflection of the energy needs of the patient.