An interventional study of Partial Cardiac Denervation in Postoperative Atrial Fibrillation and Coronary Artery Disease, sponsored by China National Center for Cardiovascular Diseases. Not yet recruiting at 5 sites in China. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-11-05.
Sponsored by China National Center for Cardiovascular Diseases · Not applicable, Interventional, and Prevention
Postoperative atrial fibrillation (POAF) is the most common arrhythmia following cardiac surgery and is associated with increased risks of mortality, stroke, myocardial infarction, and hospital readmission. The cardiac autonomic nervous system plays an important role in the development of POAF and may represent a potential target for preventive intervention.
The CALM trial is a multicenter, randomized controlled trial designed to evaluate the efficacy and safety of partial cardiac denervation for the prevention of POAF in patients undergoing isolated coronary artery bypass grafting (CABG). A total of approximately 1,470 participants will be randomly assigned in a 1:1 ratio to undergo CABG with partial cardiac denervation or CABG alone. Partial cardiac denervation consists of transection of the ligament of Marshall and resection of the Waterston fat pad.
The trial will evaluate the incidence of POAF within the first 6 postoperative days and the occurrence of long-term adverse clinical events. Participants will undergo scheduled rhythm monitoring and clinical follow-up, and all participants will be followed until the last enrolled participant completes 3 years of follow-up after surgery.
Postoperative atrial fibrillation (POAF) is a common complication after coronary artery bypass grafting (CABG) and is associated with increased risks of stroke, myocardial infarction, prolonged hospitalization, and other adverse outcomes. Autonomic imbalance and excessive activation of the intrinsic cardiac autonomic nervous system are considered important contributors to the development of POAF. Previous studies of pharmacological or biological autonomic modulation have shown variable efficacy, and their effects may be transient.
A previous single-center randomized trial conducted by the investigators showed that partial cardiac denervation, consisting of transection of the ligament of Marshall and resection of the Waterston fat pad, reduced the incidence of POAF after CABG without increasing perioperative complications. The CALM trial is designed to evaluate whether these findings can be reproduced across multiple centers and to investigate the potential long-term clinical and autonomic effects of this intervention.
This is a prospective, multicenter, randomized controlled trial involving approximately 1,470 patients undergoing isolated CABG with or without cardiopulmonary bypass. Participants will be randomly assigned in a 1:1 ratio to partial cardiac denervation in addition to standard CABG or to standard CABG alone. Centralized randomization will be stratified by participating center and baseline CHA2DS2-VASc score. Treatment allocation will be disclosed to the operating surgeon only after induction of anesthesia. Participants, outcome assessors, electrocardiographic reviewers, clinical event adjudicators, and statisticians will remain blinded to treatment allocation.
In the intervention group, the ligament of Marshall, located between the left atrial appendage and the left pulmonary veins, will be transected using electrocautery. The Waterston fat pad, located in the interatrial groove between the right atrium and the right pulmonary veins, will then be completely resected down to the epicardial surface. No additional denervation procedure will be performed in the control group. Other aspects of CABG and perioperative care will follow routine clinical practice at each participating center.
Continuous electrocardiographic monitoring will be performed during the early postoperative period, and scheduled ambulatory electrocardiographic monitoring will be conducted during follow-up. Electrocardiographic recordings will be centrally reviewed by an independent ECG Core Laboratory. Suspected clinical endpoint events will be adjudicated by an independent Clinical Event Adjudication Committee blinded to treatment allocation. Participants will undergo scheduled clinical follow-up for assessment of arrhythmias, cardiac autonomic function, and long-term clinical outcomes. All participants will be followed until the last enrolled participant has completed 3 years of follow-up after surgery.
4,857 studies on the registry are indexed under Coronary Artery Disease; 890 are open to participants now.
This study's planned enrollment of 1,470 is above the median of 124 across 3,006 interventional studies indexed under Coronary Artery Disease.
Browse Coronary Artery Disease studies →China National Center for Cardiovascular Diseases is the lead sponsor of 269 studies on the registry; 141 are open to participants now.
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Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
The share of blood the heart’s main pumping chamber (the left ventricle) pushes out with each beat, measured by an echocardiogram (heart ultrasound) or a MUGA scan. About 50–70% is normal.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
LVEF (left ventricular ejection fraction)
The share of blood the heart’s main pumping chamber (the left ventricle) pushes out with each beat, measured by an echocardiogram (heart ultrasound) or a MUGA scan. About 50–70% is normal.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
CABG alone
Partial cardiac denervation + CABG. Partial cardiac denervation consists of transection of the ligament of Marshall and resection of the Waterston fat pad.
Procedure: Partial Cardiac Denervation
The intervention has been described in previous studies. Briefly, intraoperative partial cardiac denervation is achieved by transection of the left LOM and resection of the right Waterston fat pad using electrocautery. During the procedure, the pulmonary trunk is first gently retracted to the right to expose the LOM located between the left atrial appendage and the left pulmonary veins. The LOM is then transected using electrocautery. Subsequently, the right atrium is retracted to the left to expose the Waterston fat pad located in the interatrial groove. The Waterston fat pad is completely excised with electrocautery down to the epicardial surface.
Incidence of Postoperative Atrial Fibrillation Within 6 Postoperative Days
The proportion of participants with documented new-onset postoperative atrial fibrillation (POAF). POAF is defined as an episode of atrial fibrillation characterized by irregularly irregular RR intervals and the absence of discernible P waves, lasting more than 30 seconds. Continuous electrocardiographic recordings will be centrally reviewed by the blinded ECG Core Laboratory.
Time frame: From admission to the intensive care unit after surgery until postoperative day 6.
Time to First Occurrence of the Composite Clinical Outcome
Time from surgery to the first occurrence of any component of the composite outcome, including all-cause death, stroke, systemic embolism, myocardial infarction, readmission for cardiac reasons, or post-discharge atrial fibrillation. Suspected clinical events will be adjudicated by an independent Clinical Event Adjudication Committee blinded to treatment allocation. Post-discharge atrial fibrillation events will be reviewed by the blinded ECG Core Laboratory.
Time frame: From surgery until 3 years after enrollment of the last participant, with a minimum follow-up of 3 years for each participant.
Postoperative Length of Hospital Stay
The number of days from the date of surgery to hospital discharge.
Time frame: From the date of surgery through discharge from the index hospitalization (an estimated period of up to 30 days)
Total Hospitalization Costs
Total medical costs incurred during the index hospitalization.
Time frame: From the date of surgery through discharge from the index hospitalization (an estimated period of up to 30 days)
Incidence of Perioperative All-Cause Mortality
The proportion of participants who die from any cause during the perioperative hospitalization.
Time frame: From the date of surgery through discharge from the index hospitalization (an estimated period of up to 30 days)
Incidence of Perioperative New-Onset Stroke
The proportion of participants who experience a new-onset stroke during the perioperative hospitalization, as adjudicated by the blinded Clinical Event Adjudication Committee according to predefined endpoint criteria.
Time frame: From the date of surgery through discharge from the index hospitalization (an estimated period of up to 30 days)
Incidence of Perioperative Myocardial Infarction
The proportion of participants who experience myocardial infarction during the perioperative hospitalization, as adjudicated by the blinded Clinical Event Adjudication Committee according to predefined endpoint criteria.
Time frame: From the date of surgery through discharge from the index hospitalization (an estimated period of up to 30 days)
Postoperative Atrial Fibrillation Burden Within 6 Postoperative Days
The proportion of analyzable electrocardiographic monitoring time spent in atrial fibrillation during the early postoperative monitoring period, as determined by the blinded ECG Core Laboratory.
Time frame: From admission to the intensive care unit after surgery until postoperative day 6.
Number of Postoperative Atrial Fibrillation Episodes Within 6 Postoperative Days
The total number of documented postoperative atrial fibrillation episodes per participant during the early postoperative monitoring period, as determined by the blinded ECG Core Laboratory.
Time frame: From admission to the intensive care unit after surgery until postoperative day 6.
Duration of Postoperative Atrial Fibrillation Within 6 Postoperative Days
The cumulative duration of documented postoperative atrial fibrillation episodes during the early postoperative monitoring period, as determined by the blinded ECG Core Laboratory.
Time frame: From admission to the intensive care unit after surgery until postoperative day 6.
Incidence of Post-Discharge Atrial Fibrillation
The proportion of participants with atrial fibrillation documented after discharge by scheduled 3-day ambulatory electrocardiographic monitoring or by clinically obtained electrocardiographic recordings. All suspected events will be reviewed by the blinded ECG Core Laboratory.
Time frame: From discharge until the end of study follow-up, with a minimum follow-up of 3 years for each participant.
Post-Discharge Atrial Fibrillation Burden
The proportion of analyzable ambulatory electrocardiographic monitoring time spent in atrial fibrillation during each scheduled 3-day monitoring period, as determined by the blinded ECG Core Laboratory.
Time frame: At 3 months, 1 year, and annually thereafter until study completion, with a minimum follow-up of 3 years for each participant.
Incidence of Non-Atrial Fibrillation Arrhythmias
The proportion of participants with predefined non-atrial fibrillation arrhythmias, including third-degree atrioventricular block, frequent premature atrial contractions, and frequent premature ventricular contractions, as determined by the blinded ECG Core Laboratory.
Time frame: From surgery until the end of study follow-up, with a minimum follow-up of 3 years for each participant.
Heart Rate Variability Parameters
Cardiac autonomic function will be assessed using time-domain and frequency-domain heart rate variability parameters obtained from electrocardiographic monitoring. Measurements will be centrally analyzed by the blinded ECG Core Laboratory.
Time frame: During the first 6 postoperative days and at 3 months, 1 year, and annually thereafter until study completion, with a minimum follow-up of 3 years for each participant.
Health-Related Quality of Life Assessed Using the EuroQol 5-Dimension 5-Level Questionnaire
Health-related quality of life will be assessed using the EuroQol 5-Dimension 5-Level Questionnaire (EQ-5D-5L). An EQ-5D-5L health utility index will be calculated using the Chinese population value set. The index ranges from -0.391 to 1.000, with higher scores indicating better health status. A score of 1.000 represents full health, 0 represents a health state equivalent to death, and negative values represent health states considered worse than death. Scores will be compared between the two treatment groups at scheduled follow-up assessments.
Time frame: At 3 months, 1 year, and annually thereafter until study completion, with a minimum follow-up of 3 years for each participant.
Atrial Fibrillation-Related Quality of Life Assessed Using the Atrial Fibrillation Effect on QualiTy-of-Life Questionnaire
Atrial fibrillation-related quality of life will be assessed using the Atrial Fibrillation Effect on QualiTy-of-Life Questionnaire (AFEQT). The AFEQT Overall Summary Score ranges from 0 to 100, with higher scores indicating better atrial fibrillation-related health status and quality of life and lower scores indicating greater impairment. Scores will be compared between the two treatment groups at scheduled follow-up assessments.
Time frame: At 3 months, 1 year, and annually thereafter until study completion, with a minimum follow-up of 3 years for each participant.
Incidence of Reoperation for Bleeding
The proportion of participants who require surgical re-exploration because of postoperative bleeding.
Time frame: From the date of surgery through discharge from the index hospitalization (an estimated period of up to 30 days).
Incidence of Postoperative Blood Transfusion
The proportion of participants who receive a blood transfusion after surgery during the index hospitalization.
Time frame: From the date of surgery through discharge from the index hospitalization (an estimated period of up to 30 days).
Incidence of Delayed Moderate or Greater Pericardial Effusion
The proportion of participants who develop new-onset moderate or greater pericardial effusion within 30 days after discharge from the index hospitalization, as documented by echocardiography.
Time frame: From discharge from the index hospitalization through 30 days after discharge.
Plan to share: Yes
Supporting information: Study protocol, Statistical analysis plan, Clinical study report
No publications or documents are linked to this record.
From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗
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