TactiSense IDE Trial of TactiCath SE for Paroxysmal Atrial Fibrillation: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for TactiSense IDE Trial of TactiCath SE for Paroxysmal Atrial Fibrillation (NCT03354663), a na na study. The primary outcome is Rate of Serious Adverse Events.

2. Clinical Question

3. Trial Design

The TactiSense IDE Trial, NCT03354663, is a completed, single-group clinical investigation of TactiCath SE for paroxysmal atrial fibrillation. The registry lists the phase as NA, allocation as NA, and masking as NONE. These entries do not establish a randomized comparison or a blinded assessment. The registry lists enrollment as 156.

The brief description states that the investigation was to take place at up to 35 investigational sites in the US, Europe, and Australia. Its stated purpose was to demonstrate acute safety and effectiveness of ablation with the device in people with drug-refractory recurrent symptomatic paroxysmal atrial fibrillation. It was conducted under an investigational device exemption and intended to support US market approval. The registry lists Abbott Medical Devices as sponsor.

The intervention description identifies catheter ablation with the TactiCath SE catheter to achieve pulmonary vein isolation. Because the design is single-group, the study describes outcomes after use of the device and procedure in the enrolled study population; it does not directly estimate a difference against an untreated group or another catheter group. A comparison with historical experience, if any, is not described in the registry record.

The registry gives a start date of 2017-12-11, a primary completion date of 2018-08-02, and an overall status of COMPLETED. It lists 21 outcome measures and 4 analyses, but the specific analysis procedures and how outcomes were prioritized are not reported in the registry record. The listed primary endpoint has a 30-day timeframe, while its description defines the core event window as within 7 days, with selected events included through 30 days.

4. Participant Flow and Accounting

The registry reports how participants moved through each stage of the study. All counts below are exactly as posted; missing counts are not inferred from other stages.

Enrollment to Catheter Insertion

Reasons for not completing this period:

Completed 30-day Visit

Reasons for not completing this period:

Analysis population for the primary outcome, as defined in the registry: All subjects with device inserted into vasculature and either experienced a primary endpoint event or completed 30 days of follow up.

5. Baseline Characteristics

The table reproduces the baseline characteristics posted in the registry, which describe the participants analysed at baseline and help show whether the randomized groups were comparable.

Population: Population includes all subjects with device inserted into vasculature.

6. Primary Endpoint

The registry lists the primary outcome as Rate of Serious Adverse Events, measured over 30 days.

The primary endpoint is titled Rate of Serious Adverse Events and is expressed as participants. Its description defines the main events of interest as device- or procedure-related serious adverse events occurring within 7 days of the index procedure. Events related solely to arrhythmia recurrence are excluded when there are no coexisting conditions specified in the endpoint definition. Atrial-esophageal fistula, cardiac perforation or tamponade, and pulmonary vein stenosis occurring after 7 days and through 30 days also contribute.

The endpoint includes a specified set of serious complications, including cardiac, vascular, neurological, pulmonary, and other events. The registry’s population definition includes subjects with the device inserted into the vasculature who either experienced a primary endpoint event or completed 30 days of follow-up. This definition matters because the endpoint is not simply a count of every adverse event reported during the study: event type, relationship to the device or procedure, and timing determine whether an event qualifies.

General statistical context: a safety endpoint of this kind is used to describe the occurrence of prespecified harms after a procedure or device exposure. Counting participants with an event can make the result easier to interpret than counting repeated episodes alone, but it does not show the number of events per affected participant. The registry record does not report the primary endpoint result, so the posted adverse-event summaries cannot substitute for that specific result.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

What does a single-group design estimate?

A single-group study records outcomes in participants who receive the study intervention, without a concurrent control group in the listed design. Its direct statistical target is descriptive: what outcomes were recorded among the study participants under the study conditions. It cannot, by itself, separate the effect of the device and procedure from other influences on the outcome, such as participants’ underlying condition, clinical care, or the passage of time.

General statistical context: a treatment contrast requires information about outcomes under more than one condition and a defensible basis for comparing those conditions. Random allocation can help make groups comparable on average, while masking can reduce some forms of assessment or reporting bias. The registry lists allocation as NA and masking as NONE, and the model as single-group. No concurrent comparison is listed. Those design features limit causal interpretation regardless of how precisely a descriptive count is calculated.

How should a participant count be read?

The adverse-event record reports participants with events, rather than an event rate calculated as a percentage in the primary endpoint description. It lists 21 participants with serious adverse events among 156 at risk, 25 with other adverse events among 156 at risk, and 0 deaths. A participant count indicates how many people in the listed risk group experienced an event category; it does not disclose whether any participant experienced multiple events or the number of episodes per participant.

General statistical context: counts and rates answer different questions. A rate requires a defined denominator and a clear rule for which people are included. A participant-level summary also needs rules for handling repeated events, event timing, and attribution. The primary endpoint specifies relationship, event categories, and follow-up windows; the broad adverse-event summary is not interchangeable with that narrower definition. The registry record does not report enough event-level detail in the posted summary to reconcile every adverse-event count with the primary endpoint.

What do uncertainty measures contribute?

A point estimate alone gives limited information about precision. General statistical context: a confidence interval expresses sampling uncertainty under an analysis model and its assumptions. A narrow interval indicates greater statistical precision than a wide interval, but neither guarantees that the model is appropriate or that the study population represents people outside the trial. The registry record does not report a confidence interval for the primary safety endpoint. It also does not report the primary endpoint’s numerical result, so precision around that result cannot be assessed from the endpoint entry.

For uncommon safety outcomes, the number of observed events can be small and estimates may be imprecise. General statistical context: exact or suitably designed interval methods may be considered for sparse binary outcomes, depending on the estimand and analysis plan. No particular interval method is reported in the registry record. The top adverse-event terms have percentages, but the record does not supply uncertainty intervals for those terms in the posted summary. Their percentages should therefore be read as descriptive rather than as precise estimates of risk in a broader population.

What does the sample-size planning illustration mean?

The planning assumptions describe an illustration based on the observed effect, with a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation. The effect to detect is described as a stated fraction of the observed effect. The stated instructions distinguish participants per arm for ordinary outcomes from total events for time-to-event outcomes. These are planning assumptions for an illustration, not a description of the actual single-group trial design.

General statistical context: sample-size planning asks what study size might be needed to detect a specified effect under explicit assumptions. It is not a measure of the chance that the completed trial found a real effect, and it does not repair the absence of a control group. Planning based on an observed effect can also be sensitive to how that effect was estimated. The registry record does not report the trial’s own sample-size justification, a planned effect size, or the rationale for its enrollment target. The planning illustration should not be described as observed power.

The registry lists 21 outcome measures and 4 analyses, but the statistical methods for those analyses are not reported in the registry record. The record also does not state whether analyses were adjusted for covariates, whether any model accounted for site, or which inferential procedure was used for the primary endpoint. These omissions prevent a fuller assessment of model assumptions, standard errors, or the relationship between the planned analysis and the posted summaries.

10. Exact Estimates for Each Arm

No two-arm comparison is shown for this trial, but each arm's result can still be summarized with exact interval estimates computed from the posted counts. The Clopper-Pearson interval is exact and conservative; the Wilson interval is a common closer-to-nominal alternative; the Bayesian credible interval uses a uniform Beta(1, 1) prior. For small groups the three can differ noticeably.

R code and output

arm    <- c("TactiCath SE - Safety Population")
n      <- c(149)
events <- c(7)
for (i in seq_along(n)) {
  ci <- binom.test(events[i], n[i])$conf.int          # Clopper-Pearson exact interval
  cr <- qbeta(c(0.025, 0.975), 1 + events[i], 1 + n[i] - events[i])   # Bayesian, uniform Beta(1,1) prior
  wi <- (function(x, n) { p <- x / n; z <- qnorm(0.975); d <- 1 + z^2 / n
    c((p + z^2 / (2 * n) - z * sqrt(p * (1 - p) / n + z^2 / (4 * n^2))) / d, (p + z^2 / (2 * n) + z * sqrt(p * (1 - p) / n + z^2 / (4 * n^2))) / d) })(events[i], n[i])
  cat(sprintf("ARM|%s|%d|%d|%.1f|%.1f|%.1f|%.1f|%.1f|%.1f|%.1f\n", arm[i], n[i], events[i], 100 * events[i] / n[i],
              100 * ci[1], 100 * ci[2], 100 * wi[1], 100 * wi[2], 100 * cr[1], 100 * cr[2]))
}

ARM  TactiCath SE - Safety Population  149  7  4.7  1.9  9.4  2.3  9.4  2.3  9.4

11. Multiplicity, Missing Data and Analysis Populations

The registry lists 21 outcome measures and 4 analyses. The record does not report how those outcomes were prioritized beyond identifying the Rate of Serious Adverse Events as the primary endpoint. It also does not report whether statistical testing across outcomes was adjusted for multiplicity, whether any outcomes were exploratory, or whether a hierarchy or gatekeeping strategy was specified.

General statistical context: when many hypotheses are tested, the chance of at least one apparently notable result can increase if each test is interpreted independently. Adjustment procedures or prespecified testing hierarchies can address that issue, but the appropriate approach depends on the study’s goals and analysis plan. Without the plan and outcome-level test results, the multiplicity strategy cannot be assessed from the registry record.

Missing-data handling is not reported in the registry record. The primary population definition includes participants who experienced an endpoint event or completed 30 days of follow-up, but that does not explain how incomplete follow-up, withdrawal, or unavailable event information was treated. The record does not report imputation, censoring rules, sensitivity analyses, or the number of participants with incomplete endpoint assessment.

The analysis population beyond the endpoint definition is also not reported in the registry record. It is not clear whether all enrolled participants, all participants with device insertion, or another specified population was used for each outcome. The record does not describe exclusions, protocol deviations, or analysis-set rules. These details matter because the population used for analysis affects the denominator and the interpretation of event counts. No assumptions about the missing-data or analysis-population methods can be made from the posted information.

12. Safety Results

The registry reports serious adverse events as affected participants divided by participants at risk.

Deaths

Other (non-serious) adverse events

Participants with at least one non-serious event at or above the registry's 0% reporting threshold.

Most frequent serious adverse event terms

Most frequent non-serious adverse event terms

Serious events with the highest arm-level rate: arrhythmias (4.5%), pericardial effusion (1.9%), cardiac perforation/tamponade (1.3%), atrial-esophageal fistula (0.6%), cerebrovascular accident/ stroke (0.6%).

The adverse-event summary lists 21 participants with serious adverse events among 156 at risk, 25 participants with other adverse events among 156 at risk, and 0 deaths. The serious and other categories are reported separately in the registry summary. The term list gives Arrhythmias at 4.5%, Pericardial Effusion at 1.9%, Cardiac Perforation/Tamponade at 1.3%, and three further terms at 0.6% each: Atrial-Esophageal Fistula, Cerebrovascular Accident/ Stroke, and Cholecystitis.

These summaries should be read as descriptive safety reporting, not as a direct comparison with another treatment. Nor should each listed term be assumed to qualify for the primary endpoint. That endpoint requires device- or procedure-related serious events, specified event types, and defined timing. The registry record does not provide term-by-term attribution and timing in the adverse-event summary, so the relationship between these terms and the primary endpoint cannot be determined from the listed figures alone.

General statistical context: adverse-event categories may overlap if a participant experiences more than one kind of event. Participant counts across categories should not be added to infer a total number of affected people. The registry record does not indicate in this summary how many participants had events in more than one category.

13. What the Result Does, and Does Not, Mean

The registry record describes a completed investigation of catheter ablation with TactiCath SE in people with drug-refractory recurrent symptomatic paroxysmal atrial fibrillation. It identifies a primary safety endpoint with specific event types, relationship criteria, and follow-up windows. The adverse-event summary reports serious and other event counts, a death count, and selected event terms with percentages.

Those findings are descriptive. They characterize events recorded in the study’s listed risk group, but do not establish how outcomes would compare with another catheter, another procedure, or no intervention. The single-group design provides no concurrent control for such a comparison. The registry record does not report a numerical result for the primary endpoint, and the broader serious adverse-event count cannot be substituted for it because the endpoint applies additional definitions.

The listed percentages for individual terms provide a scale for the posted event summaries, but they do not show attribution, timing, or uncertainty. The record does not report confidence intervals for the primary endpoint or the listed terms. General statistical context: a descriptive estimate may be compatible with a range of underlying event frequencies, and the amount of uncertainty depends on the data and method. A study summary without interval estimates gives less information about precision than one that reports them.

The result does not establish that the device or procedure caused every reported event, nor does the registry summary establish that an event was unrelated. It also does not establish effectiveness: no numerical effectiveness outcome is reported in the registry record described by the registry record. The stated purpose of the investigation includes effectiveness, but a stated purpose is not itself an observed result.

In short, the posted information supports reading the adverse-event figures as a descriptive account within this single-group investigation. It does not support a comparative treatment claim, a precise estimate of the primary safety endpoint, or a conclusion about effectiveness. Those boundaries follow from the design and the results reported in the registry.

14. Why This Trial Matters Statistically

This trial is statistically informative as an example of how safety descriptions and comparative evidence differ. The study concerns a specified device and procedure in a defined clinical context, and its primary endpoint has explicit event and timing rules. Those rules help clarify which events were intended to count, while the broader adverse-event listing provides additional descriptive safety information.

The single-group design is central to interpretation. A count of events after treatment can describe what happened in the study, but it does not show what would have happened to a comparable group under a different treatment. This is an important distinction when reading device investigations intended to support regulatory review: study purpose, endpoint definition, and evidence of a comparative effect are separate matters.

The record also illustrates why endpoint reporting needs to be complete. The primary endpoint is defined, yet its numerical result is not reported in the registry record. The adverse-event summaries cannot fill that gap automatically because their categories may not match the primary definition’s event relationship and timing requirements. A clear endpoint result, analysis population, and uncertainty measure would help readers understand both the observed safety experience and its precision.

Finally, the registry lists multiple outcomes and analyses, while details about multiplicity, missing data, and statistical methods are not reported. General statistical context: transparent reporting of these choices helps readers distinguish prespecified confirmatory analyses from descriptive or exploratory summaries. The study’s value for statistical interpretation therefore includes both what its adverse-event record describes and the limits created by the missing analysis details.

15. Limitations

• The posted summary statistics are the only data these results rest on; patient-level data, full protocols and statistical analysis plans are not available.
• Recalculated results are simple, unadjusted calculations from posted summaries. They do not replace the sponsor's prespecified analysis.

The most direct limitation is the single-group design. Without a concurrent control, the registry cannot support a direct estimate of comparative safety or effectiveness. Allocation is listed as NA and masking as NONE; the registry does not describe a randomized or blinded comparison.

The primary endpoint result is not reported in the registry record. Although its definition specifies device- or procedure-related serious adverse events and includes particular event windows, the posted adverse-event counts do not provide enough detail to determine which events met all of those criteria. The record also does not report a primary endpoint confidence interval or the analysis method used to estimate the endpoint.

The adverse-event summary provides participant counts, a death count, and selected term percentages, but does not report event-level timing, attribution, overlap among categories, or uncertainty for the listed terms. The record does not report the handling of incomplete follow-up, the analysis population for each outcome, or sensitivity analyses. It is therefore not possible to assess how missing information or analysis-set decisions might affect the summaries.

Although the registry lists 21 outcome measures and 4 analyses, it does not report the multiplicity strategy or sufficient detail to distinguish all confirmatory and exploratory analyses. It does not report the trial’s own sample-size justification or the statistical plan. The enrollment target and planning illustration should not be treated as evidence of precision or observed power.

These limitations concern what can be inferred from the registry record; they do not establish that unreported procedures were or were not performed. Details not present in the registry record remain unknown.

16. Related Tutorials

17. Related Statistical Calculators

18. Sources

• ClinicalTrials.gov: TactiSense IDE Trial of TactiCath SE for Paroxysmal Atrial Fibrillation — NCT03354663.
• Registry record last updated 2023-10-11; status last verified 2023-10.
• Results first posted 2019-08-20.
• Data retrieved from ClinicalTrials.gov on 2026-11-09.
• Group sizes, means, event counts and sponsor-reported p-values are reproduced as posted. Effect estimates, confidence intervals and p-values not attributed to the sponsor are independently calculated from the posted summary statistics.

19. Record Summary

NCT03354663 is the completed TactiSense IDE Trial of TactiCath SE for paroxysmal atrial fibrillation, sponsored by Abbott Medical Devices. The registry lists a single-group study, enrollment of 156, no masking, and allocation recorded as NA. The investigation was intended to evaluate acute safety and effectiveness of catheter ablation to achieve pulmonary vein isolation, under an investigational device exemption.

The primary endpoint is Rate of Serious Adverse Events, with a core event window within 7 days and specified events included through 30 days. The registry adverse-event summary lists 21 participants with serious adverse events among 156 at risk, 25 with other adverse events among 156 at risk, and 0 deaths. A numerical primary endpoint result is not reported in the registry record.

Because no concurrent control group is listed, the findings are descriptive rather than comparative. Analysis methods, missing-data handling, multiplicity procedures, and the trial’s sample-size justification are not reported in the registry record.