"With my first pacemaker, sweeping the floor or walking, I would get tired very quickly."
Dave Peterson (pacemaker patient)
Dave Peterson is one of many patients with a pacemaker who thought "he was just getting older" as he could not do the things he used to do.
When his previous pacemaker was replaced by an ALTRUA™ pacemaker with the MV blended sensor technology he really felt the difference. Now he is able to do his daily activities again, he can do more than before and really feels good again!
Click here to find more ALTRUA™ patient cases
Chronotropic incompetence refers to the inability of the heart to regulate its rate appropriately in response to physiologic stress4. There are a variety of definitions of chronotropic incompetence. In general, the diagnosis ranges from failure to achieve 70% to 85% of Age-Predicted Maximum Heart Rate (APMHR) as defined by the Wilkoff model. Clinics specialized in the treatment of cardiac diseases should use the definition they feel comfortable with.
* Percentage of age-predicted maximum heart rate (APMHR)
1. Sinus node disease manifests as symptomatic bradycardia with or without bradycardia-dependant tachycardia. Symptom-rhythm correlation must have been: spontaneously occurring drug induced where alternative drug therapy is lacking
2. Syncope with sinus node disease, either spontaneously occurring or induced at electrophysiological study
3. Sinus node disease manifests as symptomatic chronotropic incompetence: spontaneously occurring drug induced where alternative drug therapy is lackingRead more about the ESC guidelines
It is important to monitor paced patients even if not previously diagnosed with chronotropic incompetence. The prevalence of CI in the pacemaker population is anywhere from 34% to 42% at initial pacemaker implant. The Gwinn study found that the prevalence of chronotropic incompetence does increase over time in pacemaker patients6.
Percentage of patients with CI
Especially pacemaker patients that use beta blockers should be monitored closely for CI. Pacemaker patients often use beta blockers to treat a variety of conditions including arrhythmias, heart failure, hypertension and angina. Therapy with beta blockers leads to a reduction in resting and exercise heart rates. The majority of pacemaker patients being treated with beta blockers were found to be chronotropically incompetent (85%)7.
To recognise the symptoms of chronotropic incompetence in paced patients,
it is useful to verify the histograms in the pacemaker diagnostics on a regular basis.
Chronotropically incompetent patients are typically being paced at the lower rate limit.
See 2 examples below, click to enlarge