This page provides an independent statistical analysis and educational interpretation of publicly reported results. ClinicalTrials.gov provides the official trial registry record. Numerical trial results on this page are restricted to the results posted in the ClinicalTrials.gov record; calculations added by Clinical Biostats are labelled as such.
1. Trial at a Glance
This page covers the registry results for A Retrospective Study to Collect the Data From the Patients Who Had the Perimount Heart Valve Replacement Surgery in China During 2001 to 2007 (NCT02381678), a registered phase not stated study. The primary outcome is The Performance Evaluation of Perimount Heart Valve(Type:6900P and 2900) by Echocardiography.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT02381678 |
| Phase | Phase not stated |
| Condition | Mitral Valve or Aortic Valve Replacement |
| Allocation | Not Stated |
| Design model | Not Stated |
| Masking | Not Stated |
| Enrollment | 225 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Edwards (Shanghai) Lifesciences Medical Supplies Co., Ltd. |
| Results posted | Yes |
2. Clinical Question
Population
Patients who had Perimount heart valve replacement surgery at Guangdong General Hospital in China during 2001–2007. The registry reports enrollment of 225 and describes an echocardiographic assessment of all enrolled subjects 7–15 years after surgery.
Intervention
Implantation of a Perimount heart valve, identified in the registry as types 6900P and 2900. The listed device intervention is Perimount 2900/6900 Heart Valve.
Comparator
There is no separate comparator group. The study is described as a one-arm retrospective observational study, with all enrolled subjects who received the valve included in the single group.
Primary question
What does echocardiography show about Perimount heart valve performance 7–15 years after replacement surgery? The primary outcome is described as a percentage of all subjects, but the registry does not report the outcome value or the specific echocardiographic criteria used to define performance.
The registry also describes an objective of collecting post-operation information, including current living status, mortality, and the possibility of re-operation, bleeding, and thrombosis. These are stated aims, not results: the registry record does not report their outcomes in a way that establishes rates or comparisons. The primary question is therefore descriptive. It concerns the status of patients who received the device at one hospital, not whether the device performs differently from another valve or from no valve.
The retrospective design means the study concerns patients who had already undergone surgery during the stated period. Its intended later echocardiography could describe valve status among those assessed, but the registry does not provide a completed assessment result. The findings cannot be used to infer a comparative treatment effect from this one-group design.
3. Trial Design
This is a completed retrospective observational study at Guangdong General Hospital in China. Its title identifies the surgical years as 2001 to 2007, and the brief description likewise says the study sought data from patients who had Perimount valve replacement surgery there during 2001–2007. The study began in 2014-05 and its primary completion date is 2015-11. The registry lists the status as completed.
There is one study group: subjects implanted with a Perimount Heart Valve. The record describes the device as types 6900P and 2900, and lists Perimount 2900/6900 Heart Valve as the intervention. No randomized allocation or separate control group is described. Because every participant belongs to the same group, the design does not support a like-for-like comparison between treatments.
The registry lists enrollment of 225. Its brief summary separately says the study will enroll up to 200 patients, while the primary outcome description refers to all enrolled 225 subjects. The record does not explain this difference. It describes all enrolled subjects as required to return to Guangdong General Hospital for echocardiography, with the assessment timeframe stated as 7–15 years after heart valve replacement surgery.
The primary outcome is titled “The Performance Evaluation of Perimount Heart Valve (Type:6900P and 2900) by Echocardiography.” Its unit is a percentage of all subjects and its parameter is listed as a number. The registry lists one outcome measure and no analyses. It does not report the echocardiographic results, a statistical analysis plan, or details of how the outcome was to be derived. The sponsor is Edwards (Shanghai) Lifesciences Medical Supplies Co., Ltd.
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
| Stage | Age Group Under 60 Years Old | Age Group Between 60 and 70 Years Old | Age Group Above 70 Years Old |
|---|---|---|---|
| STARTED | 54 | 139 | 32 |
| COMPLETED | 54 | 139 | 32 |
| NOT COMPLETED | 0 | 0 | 0 |
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: This is one-arm study, all 225 subjects included in the Full Analysis Set.
| Characteristic | Unit | All Patients Enrolled in Study |
|---|---|---|
| Participants analysed | 225 | |
| Age, Continuous | years | 63 (16 to 78) |
| Sex: Female, Male: Female | Participants | 119 |
| Sex: Female, Male: Male | Participants | 106 |
| Etiology of subjects: Rheumatic | participants | 124 |
| Etiology of subjects: Degenerated | participants | 51 |
| Etiology of subjects: Endocardititis | participants | 6 |
| Etiology of subjects: Ischemic | participants | 18 |
| Etiology of subjects: Miscellaneous | participants | 26 |
| Preoperative Classification of NYHA assessment: Class I | participants | 5 |
| Preoperative Classification of NYHA assessment: Class II | participants | 79 |
| Preoperative Classification of NYHA assessment: Class III | participants | 96 |
| Preoperative Classification of NYHA assessment: Class IV | participants | 31 |
| Preoperative Classification of NYHA assessment: Not Known | participants | 14 |
| The numbers of valves implanted simultaneously: Single Valve Replacement | participants | 174 |
| The numbers of valves implanted simultaneously: Double Valves Replacement | participants | 48 |
| The numbers of valves implanted simultaneously: Triple Valves Replacement | participants | 3 |
| The concomitant surgery: Coronary Artery Bypass Grafting | participants | 41 |
| The concomitant surgery: Left Atrial Reduction | participants | 5 |
| The concomitant surgery: Tricuspid valvuloplasty | participants | 75 |
| The concomitant surgery: Radiofrequency Ablation | participants | 4 |
| The time for Extracorporeal Circulation and Cross Clamp in surgery: Time for Extracorporeal Circulation | minutes | 137.9 (SD 66.6) |
| The time for Extracorporeal Circulation and Cross Clamp in surgery: Time for cross clamp | minutes | 89.5 (SD 40.2) |
6. Primary Endpoint
The registry lists the primary outcome as The Performance Evaluation of Perimount Heart Valve(Type:6900P and 2900) by Echocardiography, measured over 7-15 years after heart valve replacement surgery (during 2001-2007).
| Element | Registry entry |
|---|---|
| Result type | Number |
| Measure of spread | not applicable |
| Unit | Percentage of all subjects |
| Endpoint classification | not reduced to a single comparison |
The primary endpoint is described as an echocardiographic evaluation of Perimount heart valve performance, conducted 7–15 years after replacement surgery during 2001–2007. The registry gives the unit as a percentage of all subjects and states that all enrolled subjects were required to return to Guangdong General Hospital for echocardiography. This identifies the intended assessment and its broad denominator, but not the particular echocardiographic findings that qualify as satisfactory or unsatisfactory performance.
Echocardiography is an imaging assessment of the heart and valves. In general, imaging can provide information about structure and function without relying only on symptoms or later clinical events. For a device follow-up study, a prespecified imaging measure can help describe the status of the implanted valve at assessment. That general rationale does not determine what this study counted as valve performance: the registry record does not report a definition, threshold, or component measurements.
The registry lists the endpoint as a number and gives no result value. It therefore does not establish what percentage of subjects had any particular echocardiographic finding, nor how many subjects completed the assessment. The stated percentage unit should not be treated as a reported estimate. Without the endpoint result and its operational definition, readers cannot assess its magnitude, precision, or clinical interpretation from the registry record.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The central interpretive issue is the gap between a stated assessment and a posted result. The registry describes an echocardiographic evaluation of the valve 7–15 years after surgery and names its unit as a percentage of all subjects. However, it does not report a primary endpoint value, an uncertainty interval, or an analysis. The record therefore supports a description of what the study intended to assess, but not a numerical conclusion about the observed echocardiographic performance.
The study has one group and no comparator. A one-group follow-up can describe outcomes among the people assessed, but it cannot by itself distinguish the contribution of the valve from other influences on later outcomes. Nor can it establish how those outcomes would compare with another device or a different course of care. This is a design limitation, not evidence for or against the device.
The registry lists adverse-event information by age group. For the group under 60 years old, it lists 54 at risk and 12 affected for serious events, and 54 at risk and 14 affected for other events. For the group between 60 and 70 years old, it lists 139 at risk and 60 affected for serious events, and 139 at risk and 27 affected for other events. For the group above 70 years old, it lists 32 at risk and 22 affected for serious events, and 32 at risk and 2 affected for other events. These are registry counts; the record does not explain the event definitions, observation periods, or whether the affected counts refer to people with at least one event or event occurrences. They should not be converted into comparative risks without that context.
The record also lists Death at 68.8% and Re-operation at 7.4% among the top serious terms. It does not specify the denominator or calculation behind these percentages. In particular, the 68.8% figure cannot be read as the mortality rate among all enrolled subjects on the information recorded. The study’s stated interest in mortality and re-operation does not substitute for clearly defined outcomes and denominators.
Overall, the registry documents a retrospective follow-up study, the intended echocardiographic endpoint, and selected adverse-event entries. It does not provide the primary result needed to quantify valve performance, or enough event context to establish rates over follow-up. Any interpretation should remain descriptive and limited to the information recorded.
9. Statistical Methods Explained
What can a one-group observational design establish?
In general, an observational study records outcomes without assigning participants to competing treatments. A retrospective study looks back at events and records that already exist or have already occurred. Such a design can describe the experience recorded for a group, subject to the completeness and definitions of those records. It does not create a randomized comparison. Here, the registry describes one group of subjects implanted with a Perimount Heart Valve and does not list a control group. This makes the study a follow-up description rather than a comparative trial of valve options.
A comparison requires more than separate labels or outcome counts: the groups must represent meaningful alternatives and the analysis must account for how they differ. There are no separate treatment arms in this record. Age-group entries in the adverse-event data are subdivisions for reporting, not alternative treatment groups. They do not provide a comparison of devices or establish that age caused a difference in outcomes.
What does an endpoint definition contribute?
In general, an endpoint turns a broad research question into an outcome that can be counted or assessed. A clear definition specifies what is measured, how it is assessed, the relevant time window, and how the result is summarized. The registry identifies echocardiography, a timeframe of 7–15 years after surgery, and a percentage of all subjects as the unit. It does not state which echocardiographic measurements were used, what values counted as a particular performance result, or how incomplete assessments were handled. Those missing details limit reproducibility and interpretation.
A denominator matters because a percentage has meaning only when readers know which subjects are included. The primary description refers to all enrolled 225 subjects, while the brief summary says enrollment would be up to 200. The record does not explain that difference, and no endpoint count or percentage is posted. It is therefore not possible to determine from the record how the intended denominator was applied in the final assessment.
How should precision be understood?
In general, a point estimate is a single summary of the observed data, while a confidence interval describes the uncertainty around that estimate under the assumptions of the statistical method. An interval is not a guarantee that the true value lies within it; it communicates how compatible a range of values is with the data and model. The registry record does not report a primary estimate or confidence interval. Precision cannot be evaluated without those results and the underlying endpoint data.
For event outcomes, follow-up duration and event definitions also matter. A count of affected subjects is not automatically an event rate over time. A time-to-event analysis can account for different lengths of observation, but requires information about event timing and censoring. Such an analysis is not reported in the registry record. The listed serious-event and other-event counts should therefore be read as entries in the registry, not as time-adjusted rates.
Why can over-dispersion matter?
In general, over-dispersion occurs when the variability in count data is greater than a statistical model expects. For example, count outcomes may vary more than a simple Poisson model assumes when event occurrence differs substantially across people or when events cluster. Ignoring over-dispersion can make uncertainty appear too small. This is a general statistical consideration, not a claim about this study: the registry does not report a count-data model, a dispersion assessment, or an analysis of its endpoint.
What can the adverse-event entries support?
The registry gives at-risk and affected counts for serious and other events in three age categories. These entries can be quoted descriptively, but the record does not explain the event coding, reporting rules, or follow-up duration for each category. The entries do not show whether an affected count is a count of people, episodes, or another unit. Without those definitions, interpreting them as incidence, comparing categories, or deriving a rate would go beyond what the record supports.
Similarly, a percentage attached to a serious-event term needs a clear denominator and a description of its calculation. The registry lists Death at 68.8% and Re-operation at 7.4%, but the basis for those percentages is not reported in the registry record. They should not be treated as percentages of all enrolled subjects or as risk estimates unless the denominator is established.
The record lists one outcome measure and zero analyses. It does not report a statistical analysis plan, model specifications, adjustment variables, handling of missing observations, or interim analyses. In general, these choices can affect both the estimate and its uncertainty. Their absence means readers cannot determine how any result would have been calculated or whether different analytic choices were considered. No recalculated treatment comparison or planning illustration is warranted from the information recorded, particularly because there is no separate comparison arm or reported primary result.
10. Multiplicity, Missing Data and Analysis Populations
Multiplicity concerns the risk of misleading findings when many outcomes, comparisons, subgroups, or analyses are examined. In general, prespecifying a primary outcome and analysis helps readers distinguish the main question from exploratory work. The registry lists one primary outcome measure, an echocardiographic evaluation, and no analyses. It does not report whether secondary outcomes were formally prespecified, how multiple outcomes were handled, or whether any subgroup analyses were planned. A multiplicity strategy is not reported in the registry record.
Missing data are especially relevant to the intended echocardiographic assessment. The record says all enrolled subjects were required to return for echocardiography, but does not report how many assessments were completed, whether any subjects could not be assessed, or how missing observations were handled. A requirement in a study description does not establish complete follow-up. If some assessments were unavailable, the percentage among assessed subjects could differ from a percentage using all enrolled subjects; the record does not state which approach was used in the final result.
The analysis population is also not described beyond the statement that the primary endpoint concerns all enrolled 225 subjects. The brief summary says the study would enroll up to 200 patients, and the record does not explain the difference. It does not specify whether the analysis included everyone enrolled, only those who returned, or another defined population. No exclusion rules or missing-data assumptions are reported in the registry record.
These omissions do not show that a particular analysis choice was made incorrectly. They mean the registry record does not provide enough detail to evaluate the handling of multiplicity, incomplete follow-up, or analysis populations.
11. Safety Results
The registry reports serious adverse events as affected participants divided by participants at risk.
| Arm | Participants with serious adverse events | Participants at risk | Percentage |
|---|---|---|---|
| Age Group Under 60 Years Old | 12 | 54 | 22.2% |
| Age Group Between 60 and 70 Years Old | 60 | 139 | 43.2% |
| Age Group Above 70 Years Old | 22 | 32 | 68.8% |
Other (non-serious) adverse events
Participants with at least one non-serious event at or above the registry's 5% reporting threshold.
| Arm | Participants affected of at risk |
|---|---|
| Age Group Under 60 Years Old | 14 of 54 |
| Age Group Between 60 and 70 Years Old | 27 of 139 |
| Age Group Above 70 Years Old | 2 of 32 |
Most frequent serious adverse event terms
| Event term | Organ system | Age Group Under 60 Years Old | Age Group Between 60 and 70 Years Old | Age Group Above 70 Years Old |
|---|---|---|---|---|
| Death | Cardiac disorders | 8 of 54 | 56 of 139 | 22 of 32 |
| Re-operation | Cardiac disorders | 4 of 54 | 4 of 139 | 0 of 32 |
Most frequent non-serious adverse event terms
| Event term | Organ system | Age Group Under 60 Years Old | Age Group Between 60 and 70 Years Old | Age Group Above 70 Years Old |
|---|---|---|---|---|
| SVD | Cardiac disorders | 14 of 54 | 27 of 139 | 2 of 32 |
Serious events with the highest arm-level rate: death (68.8%), re-operation (7.4%).
The registry’s adverse-event entries are organized by age group and distinguish serious events from other events. For subjects under 60 years old, the record lists 54 at risk and 12 affected for serious events, alongside 54 at risk and 14 affected for other events. For subjects between 60 and 70 years old, it lists 139 at risk and 60 affected for serious events, and 139 at risk and 27 affected for other events. For subjects above 70 years old, it lists 32 at risk and 22 affected for serious events, and 32 at risk and 2 affected for other events.
These counts should be interpreted cautiously. The registry record does not report the event definitions, observation time for each age group, or whether affected refers to people or event episodes. It also does not say whether the same subject could contribute to more than one term. The counts cannot therefore be treated as time-adjusted risks or used to infer a causal effect of age.
The record lists Death at 68.8% and Re-operation at 7.4% among the top serious terms. Their denominators and calculation are not reported in the registry record. In particular, the death percentage should not be described as the proportion of all enrolled subjects who died. These entries are not a substitute for a clearly defined mortality outcome and follow-up analysis.
12. What the Result Does, and Does Not, Mean
The record establishes that a completed, retrospective, one-group study was registered to collect follow-up information for patients who received Perimount heart valves at Guangdong General Hospital during 2001–2007. It specifies an intended echocardiographic assessment 7–15 years after surgery and identifies post-operation topics of interest, including living status, mortality, re-operation, bleeding, and thrombosis. It also records enrollment of 225 and lists selected adverse-event counts by age group.
The registry does not report the value of the primary echocardiographic endpoint. It therefore does not show a percentage of subjects with a defined valve finding, nor does it report the precision of such an estimate. Although the study objective refers to collecting clinical follow-up information, the registry entries do not provide enough context to calculate or interpret mortality, re-operation, bleeding, or thrombosis rates. The listed serious-term percentages have no stated denominator.
The one-group observational design also cannot establish how outcomes compare with another valve or treatment. Without a concurrent comparator and a suitable analysis, outcomes in this group cannot be attributed solely to the device. The study’s retrospective nature and the absence of reported endpoint definitions and follow-up completeness further constrain interpretation.
These limitations do not mean that the study found poor or favorable valve performance. They mean that the results needed to reach such a conclusion are not reported in the registry record. The appropriate reading is that the record describes the study question, design, and some safety entries, while leaving the primary clinical result and its uncertainty unavailable.
13. Why This Trial Matters Statistically
This study is statistically instructive because it separates a clearly stated research intention from a result that can be interpreted. The record names a long-term echocardiographic evaluation and gives a timeframe and outcome unit. Yet without the endpoint value, definition, and uncertainty, readers cannot quantify the finding or assess its precision. A well-described question is not itself evidence of an observed outcome.
The one-group design also illustrates the difference between follow-up and comparison. A group can be observed after surgery, but a comparison of treatments requires a suitable comparator and an analysis that accounts for differences between groups. Here there is one group of subjects with the valve. The age categories in the adverse-event entries do not create treatment comparisons and cannot resolve the absence of a control group.
Denominators and follow-up definitions are equally important. The primary outcome is described as a percentage of all subjects, while the record does not report the number with an available echocardiogram or how missing observations were handled. The adverse-event percentages are listed without a stated denominator. These details determine what a percentage means and whether readers can compare it across groups or studies.
Finally, the difference between the brief summary’s stated plan to enroll up to 200 patients and the registry’s enrollment of 225 illustrates why record details should be read together rather than assumed to describe the same quantity. The record does not explain the difference. A transparent account of enrollment, endpoint assessment, analysis populations, and results is needed for reproducible interpretation. In this record, the main statistical lesson is the limit of conclusions when those elements are not reported.
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 primary limitation is that the registry record does not report the primary endpoint result. It gives no echocardiographic estimate, interval describing precision, or underlying assessment count. The endpoint title and percentage unit do not define which imaging findings count as valve performance, so the intended measure cannot be independently interpreted or reproduced from the record.
The study has no comparator group. As a retrospective one-group study, it can describe follow-up in the enrolled group, but cannot estimate a comparative treatment effect. The record also does not report whether all enrolled subjects returned for echocardiography or how incomplete follow-up was addressed. It does not state the analysis population or the handling of missing observations.
The enrollment information is not reconciled: the record lists 225 enrolled, while the brief summary says up to 200 patients. No explanation is reported in the registry record. The adverse-event entries likewise lack definitions and follow-up context. The record does not clarify whether affected counts represent people or event occurrences, or identify the denominators behind the serious-term percentages. As a result, rates and age-group comparisons cannot be established from these entries.
The record lists one outcome measure and no analyses. A statistical analysis plan, adjustment strategy, interim analyses, and multiplicity approach are not reported in the registry record. These limitations concern what can be concluded from the recorded information; they do not establish that any unreported procedure was or was not performed.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: A Retrospective Study to Collect the Data From the Patients Who Had the Perimount Heart Valve Replacement Surgery in China During 2001 to 2007 — NCT02381678.
- Registry record last updated 2016-10-17; status last verified 2016-05.
- Results first posted 2016-10-17.
- 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.
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18. Record Summary
NCT02381678 is a completed retrospective observational study sponsored by Edwards (Shanghai) Lifesciences Medical Supplies Co., Ltd. It concerns Perimount heart valve replacement surgery at Guangdong General Hospital in China during 2001–2007. The study began in 2014-05 and has a primary completion date of 2015-11. The registry lists enrollment of 225 and describes one group of subjects implanted with Perimount Heart Valve, types 6900P and 2900.
The primary outcome is an echocardiographic evaluation 7–15 years after surgery, expressed as a percentage of all subjects. The registry lists one outcome measure and no analyses, but does not report the endpoint result or a specific definition of valve performance. It also lists adverse-event counts by age group and serious-event terms with percentages, without reporting enough detail to establish their denominators or follow-up context.
The record’s brief summary says the study would enroll up to 200 patients; the difference from the listed enrollment is not explained in the registry record.