Atrial Flutter
Conditions
Keywords
Transvenous Catheter Ablation, Radiofrequency Catheter Ablation, Atrial flutter, Catheter Ablation
Brief summary
The purpose of this study is to demonstrate the advantage of using a gold alloy tip electrode over a platinum/iridium alloy tip electrode in ablation of the cavotricuspid isthmus in patients with atrial flutter.
Detailed description
Transvenous catheter ablation has become the therapy of choice for patients with recurring, isthmus-dependent right atrial flutter. Achieving bidirectional conduction block in the cavotricuspid isthmus is decisive for both acute and long-term therapy success and essentially depends on the selected ablation method and the lesion size. By using an 8 mm tip electrode instead of a conventional 4 mm electrode, deeper lesions can be made, thus significantly reducing the required number of energy applications for achieving a bidirectional conduction block. Experimental studies have proven that using an ablation electrode made of gold alloy allows the creation of deeper lesions than with conventional platinum-iridium electrodes. Due to the greater heat conductivity of the gold alloy as opposed to platinum-iridium, the cooling of the ablation electrode is improved and more electric energy can be transmitted to the tissue at identical temperatures. The combination of both technologies in the form of an 8 mm-long gold electrode anticipates that the lesion depth required for an isthmus block can be achieved more quickly in comparison to the platinum-iridium electrode.
Interventions
DEVICEGold tip catheter
Radiofrquency ablation using gold tip catheter
DEVICEPlatinum-iridium tip catheter
Radiofrequency ablation using platinum-iridium tip catheter
Sponsors
Biotronik SE & Co. KG
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
* At least one electrocardiogram (ECG)-documented (can be older than 3 months), symptomatic, typical atrial flutter episode with either negative, sawtooth-shaped P-waves in leads II, III, and augmented voltage foot (aVF), or positive P-waves in leads II, III, and aVF * At least one persistent, typical atrial flutter episode of over 2 hours that has been documented in the history in the patient file and/or ECG * Signed informed consent form
Exclusion criteria
* Patient has recently undergone isthmus ablation * Acute coronary syndrome or myocardial infarction within the last 3 months * Acute reversible causes for atrial flutter (e.g. acute myocarditis) * Severe cardiac valvular defects * Tricuspid valve replacement * Atrial septum defect * Cardiovascular surgery scheduled within the next 6 months * Unstable medication in the last 7 days before study inclusion * New York Heart Association (NYHA) class IV * Women who are breastfeeding * Pregnancy * Abuse of drugs or alcohol * Patient is unable to participate in follow-up examinations * The patient has only partial legal competence * Participation in another clinical study * The ablation procedure presents an above average risk to the patient as compared to the normal patient group (must be noted by the physician on the appropriate form). * Right atrial thrombus Late
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Duration of Energy Application | ablation procedure | Cumulative amount of time current is flowing through the catheter tip. The current (in the radiofrequency range) is applied to ablate the cavotricuspid isthmus in the right atrium. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Ablation Success With the First Catheter | ablation procedure | Delivery of radiofrequency current was repeated until a cavotricuspid isthmus (CTI) conduction block was detected. The final bidirectional CTI block test (well documented in the literature) was performed 20 minutes after the last radiofrequency current delivery to assess ablation success (Y/N). Positive final bidirectional cavotricuspid isthmus condution block test means ablation successful. Negative final bidirectional cavotricuspid isthmus condution block test means ablation unsuccessful; ablation should be continued until success or terminated and classified as unsuccess. |
| Number of Patients With Long-term Treatment Success | 6 months after ablation | No recurrence of atrial flutter after ablation |
| Number of Patients With Charred Catheter Tips | ablation procedure | Char or coagulum formation on the catheter tip |
Countries
Czechia, Germany, Hungary
Participant flow
Recruitment details
A total of 463 patients were enrolled in the AURUM 8 study from June 2004 to March 2007 in 19 clinical centers in Germany and the Czech Republic.
Pre-assignment details
No exclusion before assignment
Participants by arm
| Arm | Count |
|---|---|
| Gold Tip Catheter Patients allocated to be ablated by 8-mm gold tip catheter | 236 |
| Pt-Ir Tip Catheter Patients allocated to be ablated by 8-mm Platinum-Iridium tip catheter | 227 |
| Total | 463 |
Withdrawals & dropouts
| Period | Reason | FG000 | FG001 |
|---|---|---|---|
| Overall Study | Adverse Event | 4 | 5 |
| Overall Study | Physician Decision | 3 | 3 |
Baseline characteristics
| Characteristic | Gold Tip Catheter | Pt-Ir Tip Catheter | Total |
|---|---|---|---|
| Age, Categorical <=18 years | 0 Participants | 0 Participants | 0 Participants |
| Age, Categorical >=65 years | 139 Participants | 135 Participants | 274 Participants |
| Age, Categorical Between 18 and 65 years | 97 Participants | 92 Participants | 189 Participants |
| Age Continuous | 66 years STANDARD_DEVIATION 10 | 66 years STANDARD_DEVIATION 11 | 66 years STANDARD_DEVIATION 11 |
| Region of Enrollment Czech Republic | 9 participants | 8 participants | 17 participants |
| Region of Enrollment Germany | 227 participants | 219 participants | 446 participants |
| Sex: Female, Male Female | 45 Participants | 35 Participants | 80 Participants |
| Sex: Female, Male Male | 191 Participants | 192 Participants | 383 Participants |
Adverse events
| Event type | EG000 affected / at risk | EG001 affected / at risk |
|---|---|---|
| deaths Total, all-cause mortality | — / — | — / — |
| other Total, other adverse events | 0 / 229 | 0 / 219 |
| serious Total, serious adverse events | 20 / 229 | 12 / 219 |
Outcome results
Primary
Duration of Energy Application
Cumulative amount of time current is flowing through the catheter tip. The current (in the radiofrequency range) is applied to ablate the cavotricuspid isthmus in the right atrium.
Time frame: ablation procedure
Population: Per protocol
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Gold Tip Catheter | Duration of Energy Application | 10.2 minute | Standard Deviation 6.9 |
| Pt-Ir Tip Catheter | Duration of Energy Application | 10.9 minute | Standard Deviation 6.9 |
p-value: 0.25t-test, 2 sided
Secondary
Ablation Success With the First Catheter
Delivery of radiofrequency current was repeated until a cavotricuspid isthmus (CTI) conduction block was detected. The final bidirectional CTI block test (well documented in the literature) was performed 20 minutes after the last radiofrequency current delivery to assess ablation success (Y/N). Positive final bidirectional cavotricuspid isthmus condution block test means ablation successful. Negative final bidirectional cavotricuspid isthmus condution block test means ablation unsuccessful; ablation should be continued until success or terminated and classified as unsuccess.
Time frame: ablation procedure
Population: per protocol
| Arm | Measure | Value (NUMBER) |
|---|---|---|
| Gold Tip Catheter | Ablation Success With the First Catheter | 216 Patients |
| Pt-Ir Tip Catheter | Ablation Success With the First Catheter | 195 Patients |
p-value: 0.042Chi-squared
Secondary
Number of Patients With Charred Catheter Tips
Char or coagulum formation on the catheter tip
Time frame: ablation procedure
Population: per protocol
| Arm | Measure | Value (NUMBER) |
|---|---|---|
| Gold Tip Catheter | Number of Patients With Charred Catheter Tips | 11 Patients |
| Pt-Ir Tip Catheter | Number of Patients With Charred Catheter Tips | 83 Patients |
p-value: <0.001Chi-squared
Secondary
Number of Patients With Long-term Treatment Success
No recurrence of atrial flutter after ablation
Time frame: 6 months after ablation
Population: per protocol
| Arm | Measure | Value (NUMBER) |
|---|---|---|
| Gold Tip Catheter | Number of Patients With Long-term Treatment Success | 225 Patients |
| Pt-Ir Tip Catheter | Number of Patients With Long-term Treatment Success | 213 Patients |
p-value: 0.53Chi-squared