Coffee Use, Physical Activity and Symptomatic Ventricular Arrhythmias in Patients With Left Ventricular Dysfunction and an ICD (CUPS-ICD)

The goal of this observational study is to learn whether caffeine consumption is associated with ventricular arrhythmias and physical activity in adults with heart failure, reduced left ventricular ejection fraction, and an implantable cardioverter-defibrillator (ICD). The main questions it aims to answer are:

Is caffeine consumption associated with the burden of premature ventricular contractions (PVCs)? Is caffeine consumption associated with the occurrence of ventricular arrhythmias, including non-sustained ventricular tachycardia (NSVT), sustained monomorphic ventricular tachycardia (SMVT), and ventricular fibrillation (VF)? Is caffeine consumption associated with the level of daily physical activity recorded by the ICD?

Participants will:

Complete a one-time questionnaire about their consumption of coffee and other caffeine-containing products during the previous 7 days.

Allow researchers to collect relevant information from their medical records. Allow researchers to use data already collected during the routine follow-up of their ICD, including information on heart rhythm abnormalities, heart rate, and physical activity.

No additional hospital visits, medical examinations, blood tests, or changes to treatment are required as part of this study.

Study Overview

• Status: Not yet recruiting
• Conditions: Ventricular Arrhythmia; ICD; HFrEF - Heart Failure With Reduced Ejection Fraction; HFmrEF
• Intervention / Treatment: Other: Questionnaire

• Study Type: Observational
• Enrollment (Estimated): 170

Contacts and Locations

Study Locations

• Belgium
  • Bruges, Belgium
    • AZ Sint-Jan Brugge
    • Contact: Dr. Jesús Diz Díaz; Phone Number: +3250452670; Email: cardiologie@azsintjan.be

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

• Sampling Method: Probability Sample

Study Population

Patients with left ventricular systolic dysfunction (LVEF <50%), i.e. HFrEF or HFmrEF, and an implantable cardioverter-defibrillator (ICD), including patients implanted with a cardiac resynchronization therapy defibrillator (CRT-D).

Description

Inclusion Criteria:

1. Written informed consent obtained prior to any study procedure.
2. Age ≥18 years.
3. Left ventricular systolic dysfunction (LVEF <50%), i.e. HFrEF or HFmrEF, documented on the most recent available transthoracic echocardiogram.
4. Presence of a transvenous implantable cardioverter-defibrillator (ICD), including cardiac resynchronization therapy defibrillators (CRT-D), implanted at least 12 months before the caffeine questionnaire.

Exclusion Criteria:

1. Presence of channelopathies.
2. Subcutaneous implantable cardioverter-defibrillator (S-ICD), which does not provide ventricular ectopic beat counters, accelerometer-derived physical activity data or antitachycardia pacing, and therefore cannot generate the primary outcome measure.
3. Inability to complete the study questionnaire on coffee and caffeinated product consumption.

Study Plan

How is the study designed?

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Burden of premature ventricular contractions (PVCs)	Burden of premature ventricular contractions (PVCs), expressed as the percentage of total recorded ventricular beats represented by PVCs (%PVC burden), as provided by the device's remote monitoring software, assessed over the 12 months immediately preceding the date of the caffeine questionnaire, averaged across all monitored days. Unit: percent (%).	12 months

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Non-sustained ventricular tachycardia (NSVT): occurrence (%)	Non-sustained ventricular tachycardia (NSVT). Untreated episodes of at least three consecutive ventricular beats above the programmed detection cut-off, lasting less than 30 seconds. For each episode, the device-assigned date and time will be recorded. Reported as occurrence (percentage of participants).	12 months
Non-sustained ventricular tachycardia (NSVT): rate	Non-sustained ventricular tachycardia (NSVT). Untreated episodes of at least three consecutive ventricular beats above the programmed detection cut-off, lasting less than 30 seconds. For each episode, the device-assigned date and time will be recorded. Reported as rate (episodes per 100 monitored days).	12 months
Non-sustained ventricular tachycardia (NSVT): distribution	Non-sustained ventricular tachycardia (NSVT). Untreated episodes of at least three consecutive ventricular beats above the programmed detection cut-off, lasting less than 30 seconds. For each episode, the device-assigned date and time will be recorded. Reported as the distribution of episodes across time.	12 months
Sustained monomorphic (SMVT) and polymorphic ventricular tachycardia (PVT/VF): occurrence (%)	Sustained monomorphic (SMVT) and polymorphic ventricular tachycardia (PVT/VF). Episodes lasting at least 30 seconds or terminated by device therapy. Reported as occurrence (percentage of participants).	12 months
Sustained monomorphic (SMVT) and polymorphic ventricular tachycardia (PVT/VF): rate	Sustained monomorphic (SMVT) and polymorphic ventricular tachycardia (PVT/VF). Episodes lasting at least 30 seconds or terminated by device therapy. Reported as rate (episodes per 100 monitored days).	12 months
Sustained monomorphic (SMVT) and polymorphic ventricular tachycardia (PVT/VF): median episode duration (seconds)	Sustained monomorphic (SMVT) and polymorphic ventricular tachycardia (PVT/VF). Episodes lasting at least 30 seconds or terminated by device therapy. Reported as median episode duration (seconds).	12 months
Sustained monomorphic (SMVT) and polymorphic ventricular tachycardia (PVT/VF): mode of termination	Sustained monomorphic (SMVT) and polymorphic ventricular tachycardia (PVT/VF). Episodes lasting at least 30 seconds or terminated by device therapy. Reported as mode of termination (percentage of episodes terminating spontaneously, by antitachycardia pacing, or by shock).	12 months
Sustained monomorphic (SMVT) and polymorphic ventricular tachycardia (PVT/VF): mean cycle length (ms)	Sustained monomorphic (SMVT) and polymorphic ventricular tachycardia (PVT/VF). Episodes lasting at least 30 seconds or terminated by device therapy. Reported as mean cycle length (milliseconds).	12 months
Physical activity (hours per day)	Physical activity, absolute. Daily physical activity recorded by the ICD accelerometer and reported by the remote monitoring platform, averaged across monitored days; platforms reporting activity as a proportion of the day are converted by multiplying by 24. Unit: hours per day.	12 months
Physical activity: mean daily activity expressed as a z-score	Physical activity, manufacturer-standardised. Each participant's mean daily activity expressed as a z-score relative to the mean and standard deviation of all study participants monitored on the same platform. Unit: standard deviation units.	12 months

Collaborators and Investigators

• Sponsor: Jean-Benoît Le Polain de Waroux

Study record dates

Study Major Dates

• Study Start (Estimated): October 1, 2026
• Primary Completion (Estimated): April 1, 2027
• Study Completion (Estimated): April 1, 2027

Study Registration Dates

• First Submitted: September 11, 2026
• First Submitted That Met QC Criteria: September 11, 2026
• First Posted (Actual): September 17, 2026

Study Record Updates

• Last Update Posted (Actual): September 17, 2026
• Last Update Submitted That Met QC Criteria: September 11, 2026
• Last Verified: September 1, 2026

More Information

Terms related to this study

• Keywords: ICD; HFrEF; Ventricular Arrhythmia; HFmrEF; Caffeine consumption
• Additional Relevant MeSH Terms: Health Care Quality, Access, and Evaluation; Investigative Techniques; Epidemiologic Methods; Data Collection; Health Care Evaluation Mechanisms; Quality of Health Care; Public Health; Environment and Public Health; Surveys and Questionnaires
• Other Study ID Numbers: CUPS-ICD

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No