Study on Safety and Performance of Medtentia Mitral Valve Repair System in Surgical Repair of Mitral Regurgitation: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Study on Safety and Performance of Medtentia Mitral Valve Repair System in Surgical Repair of Mitral Regurgitation (NCT01678144), a na na study. The primary outcome is Safety: All-cause Mortality Occurring in the Time From Surgery Through Hospital Discharge..

2. Clinical Question

3. Trial Design

The study evaluated the Medtentia Annuloplasty Ring during surgical repair of mitral regurgitation. Its stated purpose was to assess the device’s safety and performance and whether it fulfilled requirements for mitral valve annuloplasty rings. The intervention was mitral valve repair using the MAR, and the arm description says all eligible patients underwent surgical repair with that device.

This was a single-group study with an enrollment of 12. Allocation is listed as NA, and masking is listed as NONE. There is no separate control arm, so the study does not make a randomized or concurrent comparison with another repair approach. The record lists the phase as NA.

The study began on 2011-06-30, and the primary completion date is 2014-07-30. Its status is TERMINATED. The reason for termination is not reported in the registry record; the status alone does not establish why the study ended or whether planned follow-up was completed.

The primary outcome is a participant count for all-cause mortality from surgery through hospital discharge, with a timeframe of up to 7 days. The listed secondary outcomes cover mortality at several follow-up times, treatment-emergent major adverse cardiac events, adverse events and device-related events, abnormalities during follow-up, and mitral regurgitation assessed by echocardiography. These are the outcomes named in the record; numerical results for them are not reported in the registry record in the information available for this analysis.

The registry record lists 13 outcome measures and zero analysis records. It does not report a protocol-level statistical plan, a sample-size justification, or details of any interim analyses. Those omissions limit how fully the design and analysis choices can be evaluated.

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.

Before assignment: Patients qualifying for mitral valve repair surgery according to guidelines from the European Society of Cardiology (ESC) and the American Heart Association (AHA) and meeting pre-operative selection criteria. Successful implantation rate improved significantly during Stage 2 after sizing adjustment of the implant (Regular and Expanded).

Stage 1: MAR Classic

Reasons for not completing this period:

Stage 2: MAR Regular and MAR Expanded

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: Baseline data are provided for patients enrolled in the Stage 1 and Stage 2.

6. Primary Endpoint

The registry lists the primary outcome as Safety: All-cause Mortality Occurring in the Time From Surgery Through Hospital Discharge., measured over Time from surgery through hospital discharge, up to 7 days..

The primary endpoint is the count of participants experiencing all-cause mortality between surgery and hospital discharge. Its stated timeframe is up to 7 days. It is a safety endpoint: it records whether a death occurred during the specified period, rather than measuring a change in mitral regurgitation or another measure of device performance.

Participant counts are useful for communicating how many people experienced an event in the study group. In a single-group study, however, a count by itself does not show how the event frequency compares with what would have occurred under another treatment or without the device. A control group or other explicitly described comparison would be needed for that kind of contrast.

The record identifies the endpoint and its timeframe but does not report its numerical result. The adverse-event record separately lists 0 deaths, but it does not specify in that field whether its time window and endpoint definition are identical to the primary endpoint. It is therefore important not to treat that entry as a fully documented primary-endpoint result. A numerical primary-endpoint result is not reported in the registry record.

General statistical context: for a binary safety endpoint, uncertainty matters alongside the observed count. A confidence interval can communicate the range of event rates compatible with the data under the chosen statistical method. No confidence interval or method for one is reported in the registry record. With an enrollment of 12, the amount of information available for estimating uncommon events is limited; a lack of a listed event would not, by itself, establish that the event cannot occur.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

Study structure. The registry record identifies a single-group study, with all eligible participants undergoing surgical mitral valve repair using the MAR. Allocation is listed as NA and masking as NONE. This structure can document observations in the treated group, but it does not create a concurrent control group. General statistical context: a comparison between groups can help separate treatment-related differences from background event rates and other influences. Without such a comparator, observed outcomes must be interpreted descriptively.

What a participant count represents. The primary endpoint is a count of participants with all-cause mortality during a defined period. The adverse-event information also reports counts of participants affected by serious and other adverse events. Counts communicate how many participants experienced an event; they are not, on their own, a complete account of how often events occurred over time, how severe they were, or whether the device caused them. The record’s adverse-event entries list the numbers at risk and affected, but do not describe all event-level details.

Uncertainty around event estimates. General statistical context: a point estimate is the value calculated from the observed data, while a confidence interval represents uncertainty around that estimate under a specified method. Small studies generally provide less precision, especially for uncommon outcomes. This study enrolled 12 participants, so its observations cannot be expected to characterize rare events precisely. No confidence intervals or interval-estimation method are reported in the registry record. No precision estimate should be inferred from the event counts alone.

Interpreting multiple outcomes. The registry record lists 13 outcome measures, including several safety and performance outcomes. General statistical context: when many outcomes are examined, the chance of at least one apparently unusual result can increase, particularly if many statistical tests are conducted. Methods for addressing multiplicity depend on the planned questions and analysis strategy. The registry record does not report a multiplicity procedure or an inferential analysis plan. The existence of several outcomes does not itself establish that formal testing occurred.

Planning illustrations. The statistical planning illustrations use a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation; the target effect is described as a fraction of the observed effect. For time-to-event illustrations, the stated quantity is total events; for other illustrations, it is participants per arm. These are planning assumptions, not a description of the actual study design, which is single-group. Such illustrations are hypothetical and must not be interpreted as the observed number of participants needed, as an actual randomized comparison, or as observed power. The registry record does not report the trial’s own sample-size justification.

Analysis records and missing information. The record lists zero analysis records. This means no analysis entries are listed in the registry information; it does not establish why they are absent. The statistical model, any adjustments, the handling of missing observations, and the analysis populations are not reported in the registry record. General statistical context: an analysis population specifies which participants contribute to a particular analysis, while missing-data methods describe how unavailable measurements are handled. Without those details, readers cannot determine whether all enrolled participants contributed to every outcome or how incomplete follow-up was treated.

How to read the stated timeframes. Outcomes refer to different periods and assessment methods. The primary endpoint spans surgery through hospital discharge, up to 7 days. Secondary outcomes include mortality at later follow-up times and echocardiographic evaluations during surgery and at follow-up visits. A result for one timeframe or method would not automatically answer a question about another. General statistical context: matching the interpretation to the endpoint definition and measurement time is essential, because event occurrence and measured performance can depend on when and how they are assessed. The record does not report numerical results for the listed outcomes in the information available for this analysis.

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("Medtentia Annuloplasty Ring (MAR)")
n      <- c(12)
events <- c(0)
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  Medtentia Annuloplasty Ring (MAR)  12  0  0.0  0.0  26.5  0.0  24.2  0.2  24.7

11. Multiplicity, Missing Data and Analysis Populations

The registry record lists 13 outcome measures, including the primary mortality endpoint and secondary safety and performance outcomes. These cover multiple event types, follow-up periods, and echocardiographic assessments. General statistical context: testing many outcomes can increase the chance of at least one result appearing noteworthy by chance. A prespecified hierarchy or multiplicity adjustment can help define how such findings should be interpreted. A multiplicity strategy is not reported in the registry record, and the record lists zero analysis records.

The registry record does not describe missing-data handling, reasons for missing observations, or whether follow-up was complete for each outcome. The status is TERMINATED, but the reason for termination and its implications for data collection are not reported in the registry record. Termination alone does not establish that data are missing or that follow-up was incomplete.

Analysis populations are also not reported in the registry record. It is therefore unclear which participants would contribute to each outcome analysis or how any unavailable measurements would be treated. General statistical context: different analysis populations and missing-data assumptions can change the interpretation of estimates, so these details are important when evaluating completeness and potential bias.

Because there is no comparator and no reported inferential analysis plan, the available information does not support a multiplicity-adjusted treatment comparison. The stated outcomes and observed adverse-event counts can be described, but conclusions about differences, uncertainty, or the robustness of findings are limited by the absence of these methodological details.

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: atrial fibrillation (16.7%), residual mitral regurgitation leading to re-operation (8.3%), takotsubo cardiomyopathy (8.3%), peritonsilitis l.dx (8.3%), pneumonia (8.3%).

The adverse-event record lists 12 participants at risk in the MAR group. It records serious adverse events affecting 7 participants and other adverse events affecting 8 participants. These are participant counts, not counts of every individual event, and they do not show how many participants experienced events in both categories. The registry record does not report whether the categories overlap.

The listed serious-event terms and their percentages are atrial fibrillation, 16.7%; residual mitral regurgitation leading to re-operation, 8.3%; Takotsubo cardiomyopathy, 8.3%; Peritonsilitis l.dx, 8.3%; pneumonia, 8.3%; and postoperative delirium, 8.3%. These terms describe events recorded in the safety information. The entries do not, by themselves, establish that the device caused an event. Causal attribution, event-level timing, and further clinical detail are not reported in the registry record.

The safety information also lists 0 deaths. The primary endpoint has a defined timeframe of surgery through hospital discharge, up to 7 days, but the adverse-event entry does not separately specify its timeframe. The two should not be assumed to be identical without that information. Counts from 12 participants also provide limited precision for assessing uncommon events; general statistical context is that an observed count cannot rule out an event occurring in a larger population.

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

The registry record describes a single-group evaluation of the MAR during surgical mitral valve repair. It documents an enrollment of 12 and lists safety outcomes and echocardiographic measures of mitral regurgitation. The adverse-event information reports 7 participants with serious adverse events and 8 with other adverse events, each among 12 at risk. It also lists 0 deaths in the safety record. These entries describe the posted information; the primary endpoint’s numerical result is not reported in the registry record.

The record does not establish whether the recorded events were caused by the device, whether the participants with serious and other adverse events overlap, or how complete follow-up was. It also does not report numerical results for the listed secondary outcomes. A stated aim to assess safety and performance is not evidence that a particular safety threshold was met or that performance was demonstrated.

Because the study has no separate comparator, its observations cannot show how outcomes would differ under another device or surgical approach. The lack of a comparison group also means that background risks and other factors cannot be distinguished from effects associated with the intervention on the basis of this record alone.

General statistical context: an absence of a reported event in a small study does not establish that the event is impossible or that risk is negligible. Estimates from limited observations can be imprecise, particularly for uncommon outcomes. No confidence intervals are reported, so the precision of event estimates cannot be directly evaluated from the registry record.

The study is marked TERMINATED, but the reason is not reported in the registry record. This status should not be used by itself to infer the reason for stopping, the completeness of the data, or the success or failure of the study. Overall, the posted information supports a description of study design and selected safety counts, but does not provide a numerical primary-endpoint result or a comparative estimate of device effects.

14. Why This Trial Matters Statistically

This trial illustrates why study design and outcome reporting both matter in clinical biostatistics. The registry record identifies a single-group study of the MAR, with 12 participants and no separate control arm. Even when a safety event count is available, a single-group count cannot answer the same question as a comparison between treatments. The event count describes what was recorded among participants in the study; it does not establish how that experience differs from an alternative.

The primary endpoint is clearly framed as a participant count for all-cause mortality from surgery through hospital discharge, up to 7 days. Yet a numerical primary-endpoint result is not reported in the registry record. The adverse-event entry listing 0 deaths is relevant safety information, but its timeframe is not explicitly linked to the primary endpoint. This distinction shows why endpoint definitions, time windows, and reported results need to align before a number can be interpreted as answering a primary question.

The record also names multiple safety and performance outcomes, from adverse events to echocardiographic assessments of mitral regurgitation. General statistical context: multiple outcomes can address different aspects of a device’s use, but they also make clear reporting of the analysis plan important. The registry record lists zero analysis records and does not report a multiplicity strategy, missing-data approach, or analysis populations.

Finally, the planning assumptions described for statistical illustrations use equal allocation between two arms, while the actual study is single-group. Keeping planning illustrations distinct from the trial’s design prevents hypothetical calculations from being mistaken for evidence from an observed controlled comparison. These design and reporting distinctions are central to judging what the study can and cannot establish.

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 absence of a comparator is a central limitation for interpretation. The study is recorded as single-group, with allocation listed as NA. Its results therefore cannot directly estimate a difference between the MAR and another device or surgical approach. The record does not describe a control condition or a method for making an external comparison.

The enrollment is 12. General statistical context: limited enrollment constrains precision, especially for uncommon safety events and outcomes assessed at multiple follow-up times. No confidence intervals are reported in the registry record, so the uncertainty around event estimates cannot be evaluated directly from the posted information.

A numerical result for the primary endpoint is not reported in the registry record. The safety information lists 0 deaths, but does not specify that this entry corresponds exactly to the primary endpoint timeframe. Numerical results for the listed secondary outcomes are also not reported in the information available for this analysis.

The registry record lists zero analysis records and does not report the trial’s statistical analysis plan, sample-size justification, missing-data methods, analysis populations, multiplicity procedures, or interim analyses. These omissions limit assessment of how outcomes were analyzed and how incomplete observations, if any, were handled. The status is TERMINATED, but the reason is not reported in the registry record, so the status cannot clarify whether all intended assessments were completed.

The record names adverse events and device-related outcomes but does not provide enough detail to evaluate event-level timing, causal attribution, or overlap between participant categories. Together, these limitations mean the available information is best read as a partial descriptive account, rather than a complete analysis of safety or performance.

16. Related Tutorials

17. Related Statistical Calculators

18. Sources

• ClinicalTrials.gov: Study on Safety and Performance of Medtentia Mitral Valve Repair System in Surgical Repair of Mitral Regurgitation — NCT01678144.
• Registry record last updated 2019-08-09; status last verified 2019-06.
• Results first posted 2019-08-09.
• 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

The study evaluated the Medtentia Annuloplasty Ring during surgical repair of mitral regurgitation. It is recorded as a single-group study, with masking listed as NONE and allocation as NA. The registry record lists 12 participants and a TERMINATED status. Its primary endpoint is all-cause mortality from surgery through hospital discharge, up to 7 days, but a numerical result for that endpoint is not reported in the registry record.

The adverse-event information lists 7 participants with serious adverse events and 8 with other adverse events, among 12 at risk, and records 0 deaths. Secondary outcomes include mortality follow-up, cardiac and other adverse events, device-related outcomes, abnormalities, and echocardiographic assessments. The registry record lists 13 outcome measures and zero analysis records. It does not report the reason for termination, a statistical analysis plan, missing-data methods, or numerical results for the listed secondary outcomes.