Clinical trial NCT01016431: Effects of Atrial Rate-adaptive Pacing on Exercise Capacity in Patients With Chronic Heart Failure Complicated by Chronotropic Incompetence
Official title: Effects of Atrial Rate-adaptive Pacing on Exercise Capacity in Patients With Chronic Heart Failure Complicated by Chronotropic Incompetence
Study type: INTERVENTIONAL
Overall status: UNKNOWN
Phase: PHASE4
Conditions: Heart Failure
Exercise Tolerance
Keywords: cardiac pacing
heart failure
oxygen consumption
ventricular dysfunction
left, exercise tolerance
chronotropic incompetence
pacemaker programming
Lead sponsor: Federico II University
Sponsor class: OTHER
First posted: 2009-11-19
Enrollment: 20
Sex: ALL
Minimum age (years): 18
Maximum age (years): 75
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Allocation: RANDOMIZED
Intervention model: CROSSOVER
Primary purpose: TREATMENT

Brief summary: Chronotropic incompetence consists of an insufficient increase in heart rate during effort, and its presence is recognized as a common feature in patients with heart failure due to left ventricular systolic dysfunction, apparently suggesting a worse prognosis. Little is known about the possible benefits of its reversal in such patients.

The investigators working hypothesis is that the modulation of chronotropic response, as obtained by means of atrial rate-adaptive pacing may improve functional capacity in persons with chronic heart failure and chronotropic incompetence.

To explore this hypothesis,the investigators will enroll 20 patients with NYHA II/III heart failure, low left ventricular ejection fraction (\<40%) and chronotropic incompetence (Maximal heart rate \<80% of predicted value in a symptom-limited incremental test), who already underwent implantation of dual-chamber implantable defibrillator for prevention of sudden cardiac death. The study will have a randomized, double-blind, cross-over design.

The procedures, to be carried out at one month from each reprogramming (VVI backup pacing vs. AAI-R "active" pacing), will comprise: blood sampling for NT-proBNP, incremental symptom-limited cardiopulmonary exercise testing (CPX), constant-workload cardiopulmonary test (50% of max WR), quality-of-life questionnaire, 24-hour ECG monitoring.

The primary end-point will be peak oxygen consumption on CPX. Secondary end-points will include acute response to reprogramming, and data derived from constant-WR tests, Holter monitoring and QoL.


Eligibility criteria: Inclusion Criteria:

* NYHA II/III chronic heart failure on optimal medical therapy
* Sinus Rhythm
* Left ventricular ejection fraction less than 40 %
* Chronotropic incompetence on maximal exercise testing (maximum heart rate \< 80% of predicted value)
* Age 18-75
* carrier of dual chamber ICD device
* Informed Consent

Exclusion criteria:

* Unable to perform cardiopulmonary exercise testing (for any reason)
* Absolute contraindication to maximal exercise testing
* Moderate to severe anemia (Hb\<10 g/dL)
* Diagnosis of Sick Sinus Syndrome or high-degree atrioventricular block
* recent hospitalization for acute decompensated heart failure (\<1 month)
* recent acute coronary syndrome (\<3 months)
* Active neoplastic disease
* Active myocarditis / endocarditis
* Acute decompensated heart failure during study

Primary outcomes:
measure: Peak Oxygen consumption on cardiopulmonary exercise testing
timeFrame: 1 month
Secondary outcomes:
measure: Peak Heart Rate on Cardiopulmonary exercise testing
timeFrame: 1 month
measure: Quality of life as assessed by Minnesota Living with Heart Failure and SF-36 Questionnaires
timeFrame: 1 month
measure: Heart Rate Variability on Holter Monitoring
timeFrame: 1 month
measure: Acute Change in Peak Oxygen Consumption after reprogrammation
timeFrame: 1 hour
measure: NT-proBNP levels
timeFrame: 1 Month
Other outcomes:
Locations:
city: Naples
country: Italy
facility: Federico II University - Department of Internal Medicine
Study officials:
References: