Suppression Of Atrial Fibrillation With Ranolazine After Cardiac Surgery: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Suppression Of Atrial Fibrillation With Ranolazine After Cardiac Surgery (NCT01352416), a randomized phase 3 study. The primary outcome is Freedom From Any Episode of Post Operative Atrial Fibrillation Longer Than 6 Hours Duration Occurring During the Study Period..

2. Clinical Question

3. Trial Design

The registry describes a phase 3, randomized, quadruple-masked, parallel study of ranolazine and placebo after cardiac surgery. These labels indicate the design as recorded; the registry record does not provide further detail about the randomization procedure, who was masked, or how masking was maintained. The planned comparison involved participants undergoing CABG surgery or heart valve surgery, as reflected in the arm descriptions.

The ranolazine descriptions specify 1000 mg twice daily. They also state that the dose could be reduced to 500 mg if a participant was intolerant because of adverse effects or was started on diltiazem or verapamil after surgery. The placebo descriptions give corresponding placebo dosing and reduction conditions. The record does not report how many participants received each dose, whether any dose reductions occurred, or how long treatment continued.

Enrollment is recorded as 15. The adverse-event entries list participants at risk in four groups, but those entries do not establish the total randomized population or provide a complete account of participation. The record lists a start date of 2010-09 and primary completion as 2012-11. Trial status is terminated. The sponsor is Corewell Health East.

The registry describes the study objective as evaluating ranolazine as a safe, viable and potent alternative for suppressing postoperative atrial fibrillation. That is the stated objective, not a conclusion supported by the posted outcome data. In particular, the registry says the primary outcome data were not collected because the study was prematurely terminated. The reason for termination and the operational details of the trial 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

Reasons for not completing this period:

Analysis population for the primary outcome, as defined in the registry: Study was prematurely terminated. Data for this Outcome Measure were not collected

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: Subjects scheduled/undergoing cardiac surgery.

6. Primary Endpoint

The registry lists the primary outcome as Freedom From Any Episode of Post Operative Atrial Fibrillation Longer Than 6 Hours Duration Occurring During the Study Period., measured over The time between the completion of the operation and hospital discharge or 14 days post operative if the hospitalzation is prolonged.

The primary endpoint was freedom from any episode of postoperative atrial fibrillation lasting longer than 6 hours during the study period. The stated observation window ran from completion of the operation until hospital discharge, or until 14 days after surgery if hospitalization was prolonged. The registry describes the endpoint as a way to document postoperative atrial fibrillation.

This endpoint focuses on whether a participant experienced an episode exceeding a prespecified duration, rather than on every recorded rhythm event or the total time spent in atrial fibrillation. In general, defining an event threshold can make an outcome more clinically interpretable and can give investigators a consistent rule for classifying participants. However, the registry record does not report additional endpoint details such as monitoring procedures, confirmation rules, or how incomplete observation would be handled.

Most importantly, the registry states that the study was prematurely terminated and that data for this outcome measure were not collected. There is therefore no posted result for the primary endpoint and no treatment-group estimate to interpret. The endpoint’s description explains what the study intended to measure; it does not show whether participants in either group experienced or avoided the defined episodes.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

The registry identifies a randomized, quadruple-masked, parallel phase 3 design, but it does not provide a detailed statistical analysis plan. The following concepts explain how such analyses are generally interpreted; they do not describe unreported procedures from this trial.

What does randomization contribute?

General explanation: Randomization assigns participants to treatment groups using a chance-based process. When implemented as planned, it is intended to make the groups comparable with respect to measured and unmeasured characteristics at the time of assignment. This supports a treatment comparison, but it does not guarantee that groups will look identical, especially in a small study. The registry does not report the sequence-generation method, allocation concealment procedures, or group totals at randomization for this trial.

The record’s randomized designation therefore describes the trial’s stated design, not proof of how assignment was carried out. The adverse-event groups include participants at risk, but those figures are not a substitute for a full account of randomization and participant flow.

What does masking mean?

General explanation: Masking is intended to limit the influence of treatment knowledge on participant behavior, care, outcome assessment, or analysis. The registry labels this study quadruple-masked. It does not identify which roles were masked or explain how masking was maintained. The label should be reported as registered, without assuming details that are not described.

How would the primary outcome generally be compared?

General explanation: The endpoint is defined as freedom from an episode of postoperative atrial fibrillation longer than 6 hours during the stated observation period. A complete analysis would need an outcome classification for participants in each treatment group and a defined method for comparing those groups. Depending on the prespecified analysis, investigators might express results as group-level event frequencies or as a treatment contrast, with an uncertainty interval. The registry does not report the planned statistical measure or test for this endpoint.

Because the registry says the primary outcome data were not collected, it provides neither group outcome frequencies nor an effect estimate. No treatment comparison can be reconstructed from the posted record. The adverse-event counts concern different outcomes and cannot stand in for the missing primary endpoint.

What does a confidence interval communicate?

General explanation: A confidence interval communicates statistical uncertainty around an estimate under a specified method and its assumptions. A narrower interval indicates greater precision under that method; a wider interval indicates less precision. The interval does not guarantee that the true effect lies within its limits, and it cannot resolve limitations in the underlying data or design. No confidence interval for the primary endpoint is reported in the registry record, so the precision of any treatment effect is unknown.

Why does the analysis population matter?

General explanation: A trial analysis population specifies which participants contribute to an analysis and how events such as nonadherence, withdrawal, or missing follow-up are handled. Different choices can answer different questions and may affect the interpretation of results. The registry record does not report an analysis population for the primary endpoint, nor does it describe rules for handling missing outcome information. Given the statement that primary outcome data were not collected, there is no posted analysis population from which to infer an efficacy result.

What can be concluded from the registered methods?

The available design labels and endpoint definition establish what the study was intended to evaluate at a high level. They do not establish that the intended analysis was completed. The registry lists zero analyses and reports no primary outcome data. The statistical plan, including any model choice, covariate adjustment, interim analysis, or sample-size justification, is not reported in the registry record. These details should not be inferred from the phase or masking labels.

10. Multiplicity, Missing Data and Analysis Populations

The registry lists a primary outcome measure but reports that its data were not collected after premature termination. It lists no analyses. The registry record does not report a statistical plan describing how the primary endpoint would be tested or whether there were additional planned efficacy comparisons. It also does not report interim analyses, stopping boundaries, or adjustments for multiple comparisons.

General explanation: Multiplicity arises when several statistical questions are tested, since repeated testing can increase the chance of a seemingly notable result occurring by chance. A prespecified strategy can define which outcomes and comparisons are confirmatory and how uncertainty is handled across them. Without a reported analysis plan or completed primary analysis, there is no basis for describing a multiplicity strategy for this study.

The record does not report an analysis population for the primary endpoint or procedures for handling missing outcomes, withdrawals, or protocol deviations. These omissions matter because the way participants are included and missing observations are treated can affect what an estimate represents. Here, the registry’s statement is more fundamental: it says primary outcome data were not collected. There is no reported primary endpoint analysis from which to evaluate the impact of missingness or the robustness of a treatment comparison.

The registry does not report a sample-size justification, interim-analysis plan, or other details of the statistical plan. Those matters should be treated as unknown rather than reconstructed from the enrollment entry or trial classification. The available record supports no efficacy inference and does not allow assessment of planned multiplicity control or analysis-population choices.

11. Safety Results

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

Other (non-serious) adverse events

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

The registry lists serious adverse events for four groups: ranolazine with CABG surgery, placebo with CABG surgery, ranolazine with non-heart-bypass surgery, and placebo with non-heart-bypass surgery. The respective numbers at risk are 4, 7, 2, and 2. The number affected by a serious adverse event is reported as 0 in each group. The record also reports 0 other adverse events in each group.

These entries are counts for the listed safety groups. They should not be interpreted as a comparative estimate of treatment safety: the groups are small, and the registry record does not report a formal statistical comparison or further information about how events were collected. The record lists deaths as null for all four groups; deaths are therefore not reported in these entries, rather than documented as zero.

In general, a zero event count does not establish that an event cannot occur. It means that no events of that type are reported for the listed participants in the posted results. These safety figures do not provide information about the uncollected primary atrial-fibrillation outcome.

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

The record establishes that a randomized, quadruple-masked phase 3 study was registered to compare ranolazine with placebo after cardiac surgery. It describes the intended primary endpoint as freedom from a postoperative atrial fibrillation episode lasting longer than 6 hours, measured from completion of the operation to hospital discharge or 14 days after surgery if hospitalization was prolonged. It also states that the study was prematurely terminated and that primary outcome data were not collected.

Accordingly, the posted record does not establish whether the treatment groups differed on the primary endpoint. It supplies no primary-outcome estimate, no uncertainty interval, and no statistical test result. The study objective is not itself evidence of benefit or harm, and the safety counts do not answer the efficacy question.

The serious and other adverse-event counts are zero in each of the four listed groups, with the group sizes at risk also reported. These are limited descriptive entries; the registry does not report a formal safety comparison. Deaths are listed as null, so a death count is not reported. The safety information should not be expanded into a broader conclusion about safety.

General explanation: A study can be informative about a treatment effect only when the relevant outcome data and analysis are available and interpretable. Randomization and masking are important design features, but they do not replace missing outcome observations. Likewise, enrollment is not a measure of treatment effect or a substitute for a completed analysis.

The record does not report why the study was terminated, the statistical plan, the intended analysis population, or a sample-size justification. It also does not describe whether analyses were conducted outside the posted results. These unknowns limit what can be said about the study beyond its stated design, endpoint, status, and posted safety entries.

13. Why This Trial Matters Statistically

This trial is statistically notable because its design is described in detail at a high level while its intended primary outcome is unavailable. The record labels the study phase 3, randomized, quadruple-masked, and parallel, and it defines an endpoint focused on prolonged postoperative atrial fibrillation. Yet it also reports premature termination and says that primary outcome data were not collected. That combination highlights the distinction between a planned question and an answer supported by observed outcomes.

For researchers and readers, the case illustrates why design labels alone cannot establish evidential strength. Randomization can support comparability, and masking can limit some sources of bias, but those features matter to an efficacy estimate only when the relevant observations and analysis are reported. Here, no primary endpoint comparison is available, so neither the direction nor precision of an effect can be assessed.

The registry also makes clear why safety and efficacy outcomes should remain separate. Serious adverse-event counts are reported for four groups, but they do not answer the primary question about postoperative atrial fibrillation. The small reported at-risk group sizes and the absence of a reported statistical safety comparison further constrain interpretation of those descriptive counts.

General explanation: Transparent reporting of outcomes, analysis populations, missing-data handling, and statistical methods helps readers judge how a trial’s design became a result. The registry record does not report those details for this study’s primary endpoint. Its value for statistical interpretation is therefore chiefly as a clear example of the limits imposed by unavailable outcome data, rather than as a basis for estimating a treatment effect.

14. 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 principal limitation is that the registry states the primary outcome data were not collected because the study was prematurely terminated. The primary efficacy question therefore has no posted result. There is no reported treatment-group outcome count, treatment contrast, confidence interval, or test result.

The enrollment entry is 15, but the record does not provide a complete participant-flow account, group totals at randomization, or an explanation of how enrollment relates to the safety groups. The safety entries list participants at risk in each group, with zero serious and zero other adverse events reported. Deaths are listed as null. These entries do not establish a comprehensive safety profile or a comparative safety effect.

The registry record does not report the reason for termination, the statistical analysis plan, the sample-size justification, the analysis population, or methods for handling missing outcomes. It also does not report details of the randomization process, the masking procedures, adherence, dose reductions, or treatment duration. The endpoint description does not specify further monitoring or event-adjudication procedures.

These limitations mean the registered design and outcome definition cannot be used to infer what the primary results might have been. Nor can the listed safety counts substitute for the missing efficacy outcome. The available record supports description of the trial’s stated design and status, but not an estimate of the effect of ranolazine versus placebo.

15. Related Tutorials

16. Related Statistical Calculators

17. Sources

• ClinicalTrials.gov: Suppression Of Atrial Fibrillation With Ranolazine After Cardiac Surgery — NCT01352416.
• Registry record last updated 2017-01-06; status last verified 2016-11.
• Results first posted 2017-01-06.
• 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.

18. Record Summary

The registry record describes NCT01352416, a phase 3, randomized, quadruple-masked, parallel study sponsored by Corewell Health East. It lists enrollment as 15, a start date of 2010-09, primary completion as 2012-11, and status as terminated. The study objective concerned ranolazine versus placebo for suppressing postoperative atrial fibrillation after cardiac surgery.

The primary endpoint was freedom from an episode lasting longer than 6 hours during the specified postoperative observation period. The registry states that the study was prematurely terminated and that data for this outcome were not collected. It therefore reports no primary efficacy result. Serious and other adverse-event counts are reported as zero in four listed groups; deaths are not reported in those entries. The reason for termination and the detailed statistical plan are not reported in the registry record.