The FARAPULSE PersAFOne III Trial for the Treatment of Persistent Atrial Fibrillation: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for The FARAPULSE PersAFOne III Trial for the Treatment of Persistent Atrial Fibrillation (NCT05272852), a na na study. The primary outcome is Primary Safety Endpoint: Composite Safety Endpoint (CSE) Defined as the Incidence of the Following Early-onset and Late-onset Serious Adverse Events (SAEs) Which Are Device- or Procedure-related, as Adjudicated by the CEDMC.

2. Clinical Question

In statistical terms, this is a safety and feasibility question about events observed after use of the device in the enrolled group. It is not framed as an estimate of comparative benefit against another ablation approach, usual care, or no intervention. Without a concurrent control group, the registry record cannot support a direct between-group estimate of how event occurrence differs under alternative treatments.

The primary composite gathers events that vary in clinical nature and timing, including early-onset events and late-onset events. The listed early-onset events include death, myocardial infarction, persistent diaphragmatic paralysis, stroke or transient ischemic attack, thromboembolism, pericarditis, cardiac tamponade or perforation, vascular access complications requiring intervention, and heart block. The late-onset components include pulmonary vein stenosis and atrio-esophageal fistula. The endpoint definition is therefore broader than any single event type, and its interpretation depends on the composite result and the component-level information available.

The registry record does not report the number of participants meeting the primary endpoint. It also does not report component-specific primary endpoint counts. Those omissions prevent a direct description of the observed primary safety outcome from this record alone.

3. Trial Design

PersAFOne III is recorded as a completed, single-group study sponsored by Boston Scientific Corporation. Its listed phase is NA, allocation is NA, and masking is none. The registry record gives an enrollment of 80 and identifies persistent atrial fibrillation as the condition under study. The intervention is the FARAPULSE Pulsed Field Ablation System Plus, delivered as ablation using that system.

The study objective is described as assessing the safety and feasibility of endocardial creation of electrically nonconductive lesions using pulsed electrical field catheter ablation with the FARAPULSE system in persistent atrial fibrillation and associated atrial flutter. The registry record lists a start date of 2022-02-03, a primary completion date of 2024-02-09, and a status of completed. The detailed protocol, full eligibility criteria, enrollment flow, and site information are not reported in the registry record.

A single-group design describes outcomes in participants who receive the study intervention, but does not provide a contemporaneous untreated or alternative-treatment group for direct comparison. Because allocation is listed as NA and the design is single-group, no randomized treatment contrast is available in this record. Any event proportion observed in the group would describe the study cohort and follow-up, rather than establish how the event rate compares with another strategy.

Masking is listed as none. The registry record does not provide further detail about who knew the intervention assignment or whether any endpoint assessments were conducted with safeguards against knowledge of treatment. It does specify that the primary composite endpoint events are adjudicated by the Clinical Events and Data Monitoring Committee.

The record lists seven outcome measures and zero analyses. The primary endpoint timeframe is 30 days to 12 months. Secondary outcomes include a primary safety endpoint assessed at 7 days, device- or procedure-related serious adverse events, stroke or transient ischemic attack, cardioversions, and arrhythmia-related hospitalization. The outcome names do not supply the corresponding results, definitions for every measure, or analysis details. Statistical methods beyond the information explicitly listed in the record are not reported in the registry record.

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.

Overall Study

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.

6. Primary Endpoint

The registry lists the primary outcome as Primary Safety Endpoint: Composite Safety Endpoint (CSE) Defined as the Incidence of the Following Early-onset and Late-onset Serious Adverse Events (SAEs) Which Are Device- or Procedure-related, as Adjudicated by the CEDMC, measured over 30Days-12 months.

The primary endpoint is a composite safety endpoint defined as the incidence of specified serious adverse events considered device- or procedure-related and adjudicated by the Clinical Events and Data Monitoring Committee. The measure is described as the percentage of intent-to-treat subjects with one or more of these events. Its timeframe is 30 days to 12 months, and the endpoint description distinguishes early-onset events from late-onset events.

The early-onset list covers events occurring within 30 days of an index or remap procedure. It includes death, myocardial infarction, persistent diaphragmatic paralysis, stroke or transient ischemic attack, peripheral or organ thromboembolism, pericarditis, cardiac tamponade or perforation, vascular access complications requiring intervention, and heart block. Late-onset components include pulmonary vein stenosis, defined in the record as > 70% diameter reduction from baseline, and atrio-esophageal fistula. The record says these two components will be assessed for occurrence at any time during follow-up.

As a general statistical concept, a composite endpoint can capture a range of safety events in one summary measure. This may provide a broad view of whether any qualifying event occurred, but the combined result does not show which component contributed most or whether components differ in frequency or importance. Component-level results are therefore useful for understanding what a composite represents.

The primary endpoint’s participant count or percentage is not reported in the registry record. The endpoint definition is available, but the registry record does not provide the observed primary composite result or its uncertainty.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

The registry describes a single-group study with a binary primary safety endpoint expressed in terms of participants with one or more qualifying events. A binary outcome classifies each participant according to whether the specified event condition was met. In this study, the composite combines multiple serious adverse events rather than focusing on one diagnosis or procedure complication.

What does a composite endpoint summarize?

As a general statistical concept, a composite endpoint treats the occurrence of any one of several defined events as meeting the endpoint. This can make a broad safety question measurable with a single outcome, but it also combines events that may differ in severity, frequency, and clinical meaning. A composite summary does not reveal the distribution of its components. For interpretation, it is important to distinguish the overall composite from separate event counts and to know whether a participant can experience more than one component.

The primary endpoint definition includes events adjudicated as device- or procedure-related by the Clinical Events and Data Monitoring Committee. It names early-onset events within 30 days of an index or remap procedure and late-onset events through 12 months. Pulmonary vein stenosis and atrio-esophageal fistula are described as assessed at any time during follow-up. This timing structure matters because the opportunity to observe an event depends on follow-up. The registry record does not report participant-level follow-up completeness, censoring, or how incomplete observation was handled.

How should a count or percentage be read?

The record describes the primary outcome as the percentage of intent-to-treat subjects with one or more specified events, while the outcome measure is also represented as a count of participants. Counts indicate how many participants met a definition; percentages express that count relative to a stated analysis population. A meaningful percentage therefore depends on knowing the denominator and how that population was defined. Although the endpoint description names intent-to-treat subjects, the record does not report the primary endpoint count, the calculated percentage, or the operational details of the analysis population.

As a general statistical concept, a confidence interval represents a range of values compatible with the data and a specified statistical procedure. Wider intervals indicate less precision, while narrower intervals indicate greater precision under that procedure. No confidence interval for the primary endpoint is reported in the registry record, so its precision cannot be assessed from the primary outcome information available.

What can a single-group study estimate?

A single-group study can describe event occurrence among the enrolled participants under the study’s follow-up and ascertainment procedures. Without a concurrent comparison group, it does not directly estimate a difference in event frequency between the intervention and another treatment. Comparisons with external experience would require compatible definitions, populations, follow-up, and measurement processes; such a comparison is not reported in the registry record.

As a general statistical concept, random allocation helps balance measured and unmeasured characteristics on average between treatment groups, while a nonrandomized single-group design does not create that contrast. This does not make descriptive outcome counts meaningless, but it limits what those counts can establish about the effect of an intervention. In this record, allocation is NA and the model is single-group.

What does the listed planning illustration represent?

The study record also describes a planning illustration based on an observed effect, with a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation. The stated effect to detect is a fraction of the observed effect. The record explicitly characterizes this as a planning illustration rather than the trial’s own design. It is not an observed-power result and should not be read as evidence that the single-group study was designed or conducted as a two-arm comparison. The numerical planning outputs and the observed effect used for that illustration are not reported in the registry record.

As a general concept, over-dispersion occurs when outcome variability exceeds what a chosen probability model expects. It can make standard errors too small if the model does not account for the extra variability. The record does not report a model for over-dispersed outcomes, and the primary endpoint is described as a participant count rather than a repeated-event rate. No assumption about a particular statistical model should be inferred beyond the methods explicitly recorded.

What analysis details are available?

The registry record lists zero analyses. It does not report the statistical test, confidence interval method, covariate adjustment, interim analysis, missing-data method, or handling of protocol deviations. The endpoint description does identify adjudication by the Clinical Events and Data Monitoring Committee and refers to an intent-to-treat population. These details describe endpoint classification and the named analysis population, but do not supply a full statistical analysis plan. Statistical procedures beyond those stated are not reported in the registry record.

The sample-size assumptions listed for the planning illustration should also be kept separate from observed outcomes. A planning calculation asks what sample size might be associated with specified assumptions; it is not a substitute for observed estimates or their precision. It does not establish that the trial had adequate power for its primary endpoint, because the trial’s own sample-size justification is not reported in the registry record.

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("FARAPULSE™ Pulsed Field Ablation System Plus")
n      <- c(80)
events <- c(1)
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  FARAPULSE™ Pulsed Field Ablation System Plus  80  1  1.2  0.0  6.8  0.2  6.7  0.3  6.7

11. Multiplicity, Missing Data and Analysis Populations

The registry record lists seven outcome measures, including the primary safety endpoint and secondary outcomes such as safety assessed at 7 days, device- or procedure-related serious adverse events, stroke or transient ischemic attack, cardioversions, and arrhythmia-related hospitalization. It lists zero analyses. A multiplicity adjustment or hierarchy for interpreting multiple outcomes is not reported in the registry record.

As a general statistical concept, evaluating several outcomes can increase the chance of at least one apparently notable result when each is assessed separately. A prespecified hierarchy or multiplicity adjustment can address that issue, but the record does not say whether either approach was used. The existence of several registered outcomes alone does not indicate how many were analyzed or how results were interpreted.

The primary endpoint description refers to the intent-to-treat population. In general, an intent-to-treat approach aims to analyze participants according to their assigned or enrolled group, regardless of later treatment changes. The study is single-group, and the record does not provide operational details about this population, exclusions, or the number included in the primary endpoint analysis. It also does not report missing outcome data, loss to follow-up, or a missing-data strategy. Those details are not reported in the registry record, so the effect of incomplete observation on the endpoint cannot be assessed.

As a general concept, missing outcome information can affect both the estimated event frequency and its precision, particularly if missingness is related to participants’ health or event status. The available record does not describe whether outcome data were complete or how incomplete follow-up was addressed. It is therefore not appropriate to assume either that no data were missing or that missingness was handled in a particular way.

The registry record’s listing of zero analyses is a limitation of the information recorded; it does not, by itself, establish what analyses may appear in other study documents. The statistical analysis plan, interim analyses, and any adjustments made to the registered outcomes are not reported in the registry record.

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: arteriovenous fistula (2.5%), anemia (1.2%), cardiac failure congestive (1.2%), nodal rhythm (1.2%), cholecystitis (1.2%).

The adverse-event summary lists 14 participants with serious adverse events among 80 at risk, 38 participants with other adverse events among 80 at risk, and 0 deaths. These figures describe the safety reporting recorded for the FARAPULSE group. The serious-event terms listed include arteriovenous fistula at 2.5%, anemia at 1.2%, cardiac failure congestive at 1.2%, nodal rhythm at 1.2%, cholecystitis at 1.2%, and pneumonia at 1.2%.

These summary categories should not be treated as interchangeable. The number of participants affected by serious adverse events is not necessarily the number meeting the primary composite endpoint. The primary endpoint is restricted to specified device- or procedure-related events adjudicated by the Clinical Events and Data Monitoring Committee, while the adverse-event summary does not establish that every listed serious event met those criteria. The record also does not report the primary composite count or its component counts.

As a general statistical concept, participant counts describe how many people experienced an event category, while event-term listings may describe particular reported conditions. A participant may have multiple reported conditions, so term counts or percentages should not be added to obtain a participant total unless the reporting method explicitly supports that calculation. The registry record does not specify the overlap among the listed terms.

The figures come from a single-group study without a listed concurrent comparator. They describe events in the study group, not a comparative risk estimate. The record does not provide confidence intervals for these summaries or additional context needed to determine how precisely they represent event occurrence beyond the enrolled group.

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

The study is registered as a completed safety and feasibility study of the FARAPULSE Pulsed Field Ablation System Plus in persistent atrial fibrillation. Its primary endpoint is clearly defined as a composite of device- or procedure-related serious adverse events, with adjudication by the Clinical Events and Data Monitoring Committee and follow-up extending from 30 days to 12 months. The registry record also reports overall adverse-event summaries for the intervention group.

The adverse-event summary lists 14 participants affected by serious adverse events, 38 affected by other adverse events, and 0 deaths, among 80 at risk. These are descriptive observations from the recorded study group. They do not, on their own, answer whether the primary composite endpoint occurred, because the primary endpoint result is not reported and its eligibility criteria are narrower than the broad adverse-event categories.

The record does not provide a concurrent control group, a randomized comparison, or a primary endpoint estimate with a confidence interval. It therefore does not establish a comparative difference in event occurrence between the device and another treatment. Nor can the listed adverse-event data alone establish that the device caused or prevented any specific event. The study objective addresses safety and feasibility, but the registry record does not provide the primary endpoint outcome needed to quantify that question.

As a general statistical concept, absence of a reported event count is not evidence that the event did not occur. Similarly, a count observed in a study group is not a direct estimate of what would have happened to the same participants under another intervention. Causal and comparative interpretations require a suitable design and relevant analysis, details that are not reported in the registry record.

The findings that can be read from the registry are therefore limited: the study enrolled 80 participants, the intervention was a named pulsed field ablation system, the primary safety endpoint had a specified composite definition, and the adverse-event summary reports the counts and terms described. Primary endpoint occurrence, component-level results, uncertainty estimates, and detailed analysis methods are not reported in the registry record. These limits should remain explicit when interpreting the study’s statistical meaning.

14. Why This Trial Matters Statistically

This trial is statistically notable for the way its question and design align with a descriptive safety and feasibility objective. The registry identifies one intervention group and defines a broad composite safety outcome spanning early and late events. That structure makes the endpoint’s construction especially important: the overall composite would summarize whether at least one qualifying event occurred, while the listed components include different clinical events and follow-up windows.

The design also places a clear boundary on interpretation. A single-group study can describe outcomes among participants receiving the intervention, but it does not provide a direct randomized comparison with another strategy. This distinction matters whenever event counts are discussed: an observed count is not itself a comparative treatment effect. The registry’s allocation and model fields are consistent with a single-group record, not a two-arm trial.

The available safety summary makes transparent the number of participants listed with serious adverse events, other adverse events, and deaths. At the same time, the absence of the primary composite result illustrates why endpoint-level reporting matters. General adverse-event summaries do not replace the prespecified primary endpoint, especially when that endpoint uses attribution and adjudication criteria that may differ from broad safety categories.

For biostatisticians and clinical researchers, the record also illustrates the difference between registered outcome definitions and reported outcome analyses. Seven measures are listed, but zero analyses are listed. Without endpoint estimates, uncertainty measures, analysis population details, or missing-data information, readers cannot evaluate precision or the consequences of incomplete observation. Such information is necessary to assess how strongly the recorded data support conclusions about the stated safety question.

The statistical value of the record lies in making the design, endpoint definition, and available adverse-event counts visible while also exposing what is not reported. That distinction supports appropriately bounded interpretation rather than treating registration details or a descriptive event summary as a full comparative efficacy or safety analysis.

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.

Several trial-specific limits affect interpretation. First, the study is single-group, with allocation listed as NA and masking listed as none. No concurrent comparator is recorded, so the registry does not provide a randomized or controlled estimate of differences in safety outcomes. Descriptive event counts cannot establish how outcomes would compare under another treatment.

Second, the primary composite endpoint result is not reported in the registry record. The endpoint definition names serious events, attribution to the device or procedure, adjudication by the Clinical Events and Data Monitoring Committee, and follow-up timing, but the record does not give the number of participants meeting the composite or the component-specific counts. The adverse-event summary cannot be substituted for that missing endpoint result.

Third, the registry lists zero analyses. Statistical testing, confidence intervals, adjustment methods, interim analyses, and the detailed statistical analysis plan are not reported in the registry record. The record names an intent-to-treat population in the endpoint description but does not report how it was implemented or the analyzed population size.

Fourth, missing-data handling and follow-up completeness are not reported in the registry record. This is relevant to a safety endpoint spanning 30 days to 12 months, because incomplete observation may affect whether an event is captured. The record does not state whether participants had complete follow-up or how any unavailable outcomes were handled.

Finally, the adverse-event terms and summary counts do not provide enough information to determine overlap between categories or their relation to the primary composite. The registry record also does not give further eligibility, procedural, or site details that might help assess how broadly the enrolled group represents other populations. These are limitations of the information recorded and should not be resolved by assumption.

16. Related Tutorials

17. Related Statistical Calculators

18. Sources

• ClinicalTrials.gov: The FARAPULSE PersAFOne III Trial for the Treatment of Persistent Atrial Fibrillation — NCT05272852.
• Registry record last updated 2025-01-08; status last verified 2025-01.
• Results first posted 2025-01-08.
• 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

NCT05272852 is a completed, single-group feasibility study of the FARAPULSE Pulsed Field Ablation System Plus in persistent atrial fibrillation. The registry lists an enrollment of 80, no masking, and no concurrent comparator. The primary outcome is a composite of specified device- or procedure-related serious adverse events adjudicated by the Clinical Events and Data Monitoring Committee, with a timeframe of 30 days to 12 months.

The registry’s adverse-event summary lists 14 participants with serious adverse events, 38 with other adverse events, and 0 deaths among 80 at risk. The primary composite result, component counts, confidence intervals, missing-data approach, and detailed analysis plan are not reported in the registry record. The study therefore offers descriptive safety information but no recorded primary endpoint estimate or direct comparative treatment effect.