AtrioVentricular Nodal Reentrant Tachycardia, Heart Disease, Supraventricular Tachycardia
Conditions
Keywords
Cardiac cryoablation, AVNRT, heart disease, tachycardia, AtrioVentricular Nodal Reentrant Tachycardia, Supraventricular tachycardia, SVT
Brief summary
ICY-AVNRT (Intracardiac CrYoablation for AtrioVentricular Nodal Reentrant Tachycardia) is a prospective multi-center, nonrandomized, single arm, controlled, unblinded, investigational clinical study. The purpose of this clinical study is to demonstrate the safety and effectiveness of the Freezor® Xtra Cardiac CryoAblation Catheter for the cryoablation of the conducting tissues of the heart in the treatment of patients with atrioventricular nodal reentrant tachycardia (AVNRT) using an endocardial approach.
Interventions
DEVICEFreezor Xtra Cryoablation Catheter
Freezor® Xtra Cardiac CryoAblation applied for cryoablation of the conducting tissues of the heart in the treatment of patients with atrioventricular nodal reentrant tachycardia using an endocardial approach.
Sponsors
Medtronic Cardiac Ablation Solutions
Study design
Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
TREATMENT
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
Pre-Electrophysiology Study Inclusion Criteria: * Supraventricular tachycardia (SVT) compatible with atrioventricular nodal reentrant tachycardia (AVNRT), documented by ECG, TTM, Holter or event monitor Pre-Electrophysiology Study
Exclusion criteria
* History of sustained (≥30 seconds) of ventricular tachycardia * Atrial tachycardia or other arrhythmia that could be confused with AVNRT * Reversible cause of SVT * History of previous AVNRT ablation * Therapy with amiodarone within last 90 days * Unstable angina/myocardial infarction/open heart surgery in past 60 days * New York Heart Association (NYHA) Classification III or IV currently or within the past 90 days * Implantable cardiac rhythm device * Atrioventricular block (first degree (PR interval ≥ 220ms), second degree, or third degree) or left bundle branch block * Stroke or transient ischemic attack within the past 180 days * Life expectancy less than 12 months * Female known to be pregnant * Unable/unwilling to give informed consent * Unable/unwilling to comply with follow-up visits and study requirements * Less than 18 years of age * Active systemic infection * Cryoglobulinemia * Other conditions where the manipulation of the catheter would be unsafe (for example, intracardiac mural thrombus) * Participating in a concurrent clinical study that may confound the results of this study Post-Electrophysiology Study Inclusion Criteria: * Subject must have one electrophysiology study documented inducible sustained (greater than or equal to 15 seconds) supraventricular tachycardia that is classified as AVNRT. Post-Electrophysiology Study
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Chronic Effectiveness (Through 6 Months) of the Freezor Xtra Catheter for the Treatment of AVNRT Using an Endocardial Approach. | 6 months | Subjects must have met both of the following acute and chronic conditions to be considered a chronic effectiveness (treatment) success: * Acute Success: The inability to induce more than one echo beat by the same pacing maneuvers that induced AVNRT before cryoablation (with drug provocation if required for induction before cryoablation) at the conclusion of the study cryoablation procedure assessment. * Chronic Success: Lack of documented recurrence of clinical AVNRT during the 6-month follow-up period after the study cryoablation procedure. |
| Chronic Safety (Through 6 Months) of the Freezor Xtra Catheter When Used for the Treatment of AVNRT Using an Endocardial Approach. | 6 Months | Subjects who had at least one safety event during or after their cryoablation procedure or through 6 months of follow-up are considered a primary (chronic) safety failure. A safety event is defined as the occurrence of any adverse event that is adjudicated by the AE Adjudication Committee as being serious and study ablation procedure-related and/or Freezor Xtra Catheter related that: 1) Resulted in death, 2) Resulted in a life-threatening illness or injury, 3) Resulted in permanent impairment of a body function or permanent damage to a body structure, 4) Necessitated significant intervention, such as major surgery or even intravenous medical therapy (e.g., vasopressors), to prevent permanent impairment of a body function or permanent damage to a body structure, or 5) Required in-patient hospitalization or a prolongation of an existing hospital stay. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Chronic Effectiveness (Through 6 Months) of the Freezor Xtra Catheter for the Treatment of AVNRT in Subjects Who Achieved Acute Procedural Success. | 6 Months | If there was no documented evidence of AVNRT recurrence in the post-procedure 6-month follow-up period, the subject is counted as a chronic effectiveness success. The AE Adjudication Committee adjudication of AVNRT recurrence is used to classify subjects for this endpoint. |
Countries
Canada, United States
Participant flow
Recruitment details
Thirty-seven (37) centers (8 in Canada, 29 in the US) confirmed participation in the study, with enrollments having occurred at 34 of those centers. First study enrollment occurred on 14-MAY-2012 and the last enrollment occurred on 25-FEB-2015.
Participants by arm
| Arm | Count |
|---|---|
| mITT Set The modified intent-to-treat (mITT) set. | 397 |
| Total | 397 |
Withdrawals & dropouts
| Period | Reason | FG000 |
|---|---|---|
| Overall Study | Exited prior to EP study | 22 |
| Overall Study | Inclusion/exclusion criteria not met | 151 |
| Overall Study | Met inclusion/exclusion, not treated | 2 |
Baseline characteristics
| Characteristic | mITT Set |
|---|---|
| Age, Continuous | 52.6 years STANDARD_DEVIATION 13.9 |
| Race/Ethnicity, Customized American Indian or Alaska Native | 1 Participants |
| Race/Ethnicity, Customized Asian | 10 Participants |
| Race/Ethnicity, Customized Black or African American | 16 Participants |
| Race/Ethnicity, Customized Hispanic or Latino | 4 Participants |
| Race/Ethnicity, Customized Native Hawaiian or Pacific Islander | 0 Participants |
| Race/Ethnicity, Customized Not reportable per local laws or regulations | 0 Participants |
| Race/Ethnicity, Customized Other race | 2 Participants |
| Race/Ethnicity, Customized Subject/physician chose not to provide information | 10 Participants |
| Race/Ethnicity, Customized Two or more races | 1 Participants |
| Race/Ethnicity, Customized White or Caucasian | 353 Participants |
| Sex: Female, Male Female | 279 Participants |
| Sex: Female, Male Male | 118 Participants |
Adverse events
| Event type | EG000 affected / at risk |
|---|---|
| deaths Total, all-cause mortality | — / — |
| other Total, other adverse events | 197 / 397 |
| serious Total, serious adverse events | 30 / 397 |
Outcome results
Primary
Chronic Effectiveness (Through 6 Months) of the Freezor Xtra Catheter for the Treatment of AVNRT Using an Endocardial Approach.
Subjects must have met both of the following acute and chronic conditions to be considered a chronic effectiveness (treatment) success: * Acute Success: The inability to induce more than one echo beat by the same pacing maneuvers that induced AVNRT before cryoablation (with drug provocation if required for induction before cryoablation) at the conclusion of the study cryoablation procedure assessment. * Chronic Success: Lack of documented recurrence of clinical AVNRT during the 6-month follow-up period after the study cryoablation procedure.
Time frame: 6 months
Population: The modified intent-to-treat (mITT) set consists of subjects who signed the ICY-AVNRT consent form and met all Pre-EP and Post-EP study inclusion and no exclusion criteria who had a Freezor Xtra Cardiac Cryoablation Catheter inserted into the vasculature for the purpose of the ICY-AVNRT study.
| Arm | Measure | Category | Value (COUNT_OF_PARTICIPANTS) |
|---|---|---|---|
| mITT Set | Chronic Effectiveness (Through 6 Months) of the Freezor Xtra Catheter for the Treatment of AVNRT Using an Endocardial Approach. | Chronic effectiveness success | 368 Participants |
| mITT Set | Chronic Effectiveness (Through 6 Months) of the Freezor Xtra Catheter for the Treatment of AVNRT Using an Endocardial Approach. | Chronic effectiveness failure | 29 Participants |
Comparison: The following hypothesis was tested at a one-sided 0.025 significance level.~Ho: PE ≤ 0.83~Ha: PE \> 0.83~Where PE is the probability of a subject achieving chronic effectiveness success at the 6-month follow-up and 0.83 (83%) is the pre-specified performance goal.p-value: <0.000195% CI: [0.895, 0.948]Kaplan-Meier log-log 95% CI
Primary
Chronic Safety (Through 6 Months) of the Freezor Xtra Catheter When Used for the Treatment of AVNRT Using an Endocardial Approach.
Subjects who had at least one safety event during or after their cryoablation procedure or through 6 months of follow-up are considered a primary (chronic) safety failure. A safety event is defined as the occurrence of any adverse event that is adjudicated by the AE Adjudication Committee as being serious and study ablation procedure-related and/or Freezor Xtra Catheter related that: 1) Resulted in death, 2) Resulted in a life-threatening illness or injury, 3) Resulted in permanent impairment of a body function or permanent damage to a body structure, 4) Necessitated significant intervention, such as major surgery or even intravenous medical therapy (e.g., vasopressors), to prevent permanent impairment of a body function or permanent damage to a body structure, or 5) Required in-patient hospitalization or a prolongation of an existing hospital stay.
Time frame: 6 Months
Population: The modified intent-to-treat (mITT) set consists of subjects who signed the ICY-AVNRT consent form and met all Pre-EP and Post-EP study inclusion and no exclusion criteria who had a Freezor Xtra Cardiac Cryoablation Catheter inserted into the vasculature for the purpose of the ICY-AVNRT study.
| Arm | Measure | Category | Value (COUNT_OF_PARTICIPANTS) |
|---|---|---|---|
| mITT Set | Chronic Safety (Through 6 Months) of the Freezor Xtra Catheter When Used for the Treatment of AVNRT Using an Endocardial Approach. | Chronic safety failure | 4 Participants |
| mITT Set | Chronic Safety (Through 6 Months) of the Freezor Xtra Catheter When Used for the Treatment of AVNRT Using an Endocardial Approach. | Chronic safety success | 393 Participants |
Comparison: The following hypothesis was tested at a one-sided 0.025 significance level.~Ho: Ps ≥ 0.07~Ha: Ps \< 0.07~Where Ps is the probability of a subject experiencing at least one safety event through 6 months with a 0.07 pre-specified performance goal.p-value: <0.000195% CI: [0.004, 0.027]Kaplan-Meier log-log 95% CI
Secondary
Chronic Effectiveness (Through 6 Months) of the Freezor Xtra Catheter for the Treatment of AVNRT in Subjects Who Achieved Acute Procedural Success.
If there was no documented evidence of AVNRT recurrence in the post-procedure 6-month follow-up period, the subject is counted as a chronic effectiveness success. The AE Adjudication Committee adjudication of AVNRT recurrence is used to classify subjects for this endpoint.
Time frame: 6 Months
Population: The 378 mITT subjects who had acute procedural success with cryoablation for the treatment of AVNRT are included in this analysis.
| Arm | Measure | Category | Value (COUNT_OF_PARTICIPANTS) |
|---|---|---|---|
| mITT Set | Chronic Effectiveness (Through 6 Months) of the Freezor Xtra Catheter for the Treatment of AVNRT in Subjects Who Achieved Acute Procedural Success. | Chronic effectiveness success | 368 Participants |
| mITT Set | Chronic Effectiveness (Through 6 Months) of the Freezor Xtra Catheter for the Treatment of AVNRT in Subjects Who Achieved Acute Procedural Success. | Chronic effectiveness failure | 10 Participants |
Comparison: The following hypothesis was tested at a one-sided 0.025 significance level.~Ho: PE ≤ 0.80~Ha: PE \> 0.80~Where PE is the probability of a subject achieving chronic effectiveness success at 6-month follow-up, and 0.80 is the pre-specified performance goal. As pre-defined in the study protocol, this hypothesis is tested if the primary effectiveness objective null hypothesis (Ho) is rejected.p-value: <0.000195% CI: [0.95, 0.985]Kaplan-Meier log-log 95% CI