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 The ShortCut™ Study Protocol (NCT04952909), a na na study. The primary outcome is (Number of Patients With) ShortCut™ Device- and/or ShortCut™ Procedure-related Mortality and All Cause Stroke.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT04952909 |
| Phase | NA |
| Condition | Risk of Coronary Obstruction Following Transcatheter Aortic Valve Replacement (TAVR) Procedure |
| Allocation | Not applicable (single group) |
| Design model | Single Group |
| Masking | None (open label) |
| Enrollment | 60 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Pi-cardia |
| Results posted | Yes |
2. Clinical Question
Population
Patients undergoing a valve-in-valve (ViV) transcatheter aortic valve replacement (TAVR) for an approved ViV indication who were considered at risk for TAVR-induced coronary artery ostium obstruction. The registry record does not report additional eligibility details or describe the characteristics of the enrolled participants.
Intervention
The ShortCut™ device, intended to split bioprosthetic aortic valve leaflets in the setting of a ViV TAVR procedure. The registry describes the device as the sole intervention and identifies the study as open-label.
Comparator
There was no separate comparator arm. This was a prospective, non-randomized, single-arm study, so its record does not provide a concurrent control group for estimating a comparative treatment effect.
Primary question
The primary endpoint counts participants with ShortCut™ device- and/or procedure-related mortality and all-cause stroke by discharge or 7 days after the procedure, whichever occurred first. The registry record does not report the observed result for this endpoint.
The clinical context recorded for the study is coronary obstruction risk following TAVR. The stated aim was to demonstrate the safety and effectiveness of the device in patients facing that risk during a ViV procedure. These aims describe the study's purpose, not a finding that either safety or effectiveness was established.
The design can describe outcomes observed among participants treated with ShortCut™ in this study. Without a comparator group, it cannot directly determine how those outcomes compare with outcomes under another procedure or device. The registry record also does not report participant-level clinical characteristics, eligibility criteria in detail, or a separate effectiveness endpoint result. Those omissions limit how specifically the enrolled population and the scope of the study's conclusions can be characterized.
3. Trial Design
The registry identifies NCT04952909 as a prospective, multicenter, non-randomized, single-arm, open-label clinical study of the ShortCut™ device. The study status is completed. The recorded start date is 2022-01-21, and the primary completion date is 2023-09-30. Enrollment is listed as 60. The phase is recorded as NA, and allocation is also recorded as NA.
All participants were assigned to the ShortCut™ device group; the registry record describes no parallel control arm. With no random allocation or concurrent comparator, the study is not a randomized comparison. Outcomes in the treated group can be described, but differences that might have occurred under another treatment strategy cannot be estimated from this design alone. The absence of a control group also means that event rates cannot be separated from the background risks of the procedure and the participants' clinical circumstances using this study's data alone.
Open-label means that masking was not used, consistent with the registry's masking entry of NONE. The record does not report further detail about who knew treatment assignments or whether outcome assessors were blinded. It identifies Pi-cardia as the sponsor and ShortCut™ as the device intervention. Its study description concerns splitting bioprosthetic aortic valve leaflets for patients undergoing ViV TAVR who are at risk of TAVR-induced coronary artery ostium obstruction.
The registry lists a primary endpoint and secondary outcomes that include all-cause mortality, all-cause stroke, coronary obstruction, myocardial infarction with new evidence of coronary artery obstruction requiring intervention, major vascular complications, cardiac tamponade, acute kidney injury, and access-related type 3-4 bleeding. It records 16 outcome measures overall, but the descriptions and reported results are not complete enough to characterize every measure. The registry record does not report a detailed statistical analysis plan, participant flow, or analysis populations.
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: 66 subjects were found eligible per protocol. 60 subjects were treated with the device (started), after 6 subjects dropped out prior to treatment.
Overall Study
| Stage | ShortCut™ |
|---|---|
| STARTED | 60 |
| 30 Days Follow up | 58 |
| 90 Days Follow up | 57 |
| COMPLETED | 57 |
| NOT COMPLETED | 3 |
Reasons for not completing this period:
| Reason | ShortCut™ |
|---|---|
| Death | 3 |
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: Includes all patients that were treated with the ShortCut device
| Characteristic | Unit | ShortCut™ |
|---|---|---|
| Participants analysed | 60 | |
| Age, Continuous | Years | 77.0 (SD 9.6) |
| Sex: Female, Male: Female | Participants | 42 |
| Sex: Female, Male: Male | Participants | 18 |
| Ethnicity (NIH/OMB): Hispanic or Latino | Participants | 1 |
| Ethnicity (NIH/OMB): Not Hispanic or Latino | Participants | 46 |
| Ethnicity (NIH/OMB): Unknown or Not Reported | Participants | 13 |
| Race (NIH/OMB): American Indian or Alaska Native | Participants | 0 |
| Race (NIH/OMB): Asian | Participants | 1 |
| Race (NIH/OMB): Native Hawaiian or Other Pacific Islander | Participants | 0 |
| Race (NIH/OMB): Black or African American | Participants | 1 |
| Race (NIH/OMB): White | Participants | 42 |
| Race (NIH/OMB): More than one race | Participants | 0 |
| Race (NIH/OMB): Unknown or Not Reported | Participants | 16 |
| Surgical risk: Extremely high | Participants | 6 |
| Surgical risk: HIgh | Participants | 54 |
| Coronary artery disease | Participants | 26 |
| Renal impairment: Severe | Participants | 20 |
| Renal impairment: Moderate | Participants | 24 |
| Renal impairment: None/mild | Participants | 16 |
| Prior coronary artery bypass grafting | Participants | 13 |
| Prior stroke | Participants | 7 |
| Failed Valve Type: Surgical Aortic Valve Replacement (SAVR) | Participants | 58 |
| Failed Valve Type: Transcatheter Aortic Valve Replacement (TAVR) | Participants | 2 |
| Aortic valve disease: Aortic Stenosis (AS) | Participants | 35 |
| Aortic valve disease: Aortic Regurgitation (AR) | Participants | 7 |
| Aortic valve disease: Mixed failure (both Aortic Stenosis and Aortic Regurgitation) | Participants | 18 |
6. Primary Endpoint
The registry lists the primary outcome as (Number of Patients With) ShortCut™ Device- and/or ShortCut™ Procedure-related Mortality and All Cause Stroke, measured over Discharge or at 7 days post-procedure, whichever occurs first.
| Element | Registry entry |
|---|---|
| Result type | Count Of Participants |
| Measure of spread | not applicable |
| Unit | Participants |
| Endpoint classification | Binary Endpoint |
The primary endpoint is the number of participants with ShortCut™ device- and/or ShortCut™ procedure-related mortality and all-cause stroke. The assessment timeframe is discharge or 7 days post-procedure, whichever occurs first. The registry record does not report the observed count or an analysis result for this endpoint.
The endpoint combines mortality attributed to the device and/or procedure with all-cause stroke. In general, a composite endpoint can capture more than one clinically important type of outcome in a single measure. Its interpretation depends on the component definitions, the rules for counting participants who experience more than one component, and the time window used. The registry record does not report detailed operational definitions or rules for handling participants with multiple events, so those details cannot be assessed from the record.
The stated endpoint is a participant count, rather than a continuous measurement. It is focused on serious outcomes during the early post-procedure period. In general, such an endpoint can be used to describe safety outcomes associated with a device and procedure. It does not, by itself, establish a comparison with another approach, and the registry record does not report a comparative analysis. The stated study aim includes safety and effectiveness, but the primary endpoint description alone does not define or report a separate measure of effectiveness.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The record identifies a completed study with enrollment of 60 participants, but it does not report the primary endpoint result. Consequently, the central safety outcome cannot be quantified from the registry record. Completion status and enrollment describe the study's administrative status and scale; they are not substitutes for an endpoint estimate.
The safety information that is reported includes 13 participants with serious adverse events and 5 with other adverse events, with 60 at risk in each category. The record also lists 3 deaths. It identifies permanent pacemaker at 10.0%, coronary obstruction at 5.0%, myocardial infarction with new evidence of coronary artery obstruction requiring intervention at 3.3%, acute kidney injury stage 3-4 at 3.3%, all-cause stroke at 1.7%, and cardiac tamponade at 1.7% among the leading serious adverse event terms. These entries describe reported safety events; the record does not establish that these terms are mutually exclusive, nor does it provide enough detail to reconcile each term with the participant-level totals.
No inferential analyses are listed in the registry record. There are no reported confidence intervals, p-values, adjusted estimates, or tests for the primary outcome. Without an estimate and its uncertainty, the precision of the primary endpoint result cannot be assessed. The safety counts and listed event percentages are descriptive entries, not evidence of a comparative effect.
The single-arm design further constrains interpretation. An observed event among participants receiving the device cannot be contrasted with a concurrent control group in this record. Therefore, the data cannot isolate the effect of the device from the effects of the underlying procedure, participant characteristics, or other factors. This is a design limitation, not a claim about the direction or size of any effect.
The registry record does not report detailed eligibility criteria, baseline characteristics, participant disposition, missing-data handling, outcome adjudication, or analysis populations. These omissions make it difficult to determine how completely the reported safety counts represent the enrolled group or how outcomes were classified. The record also does not report the primary endpoint outcome despite listing the study as completed. Taken together, the available information supports a description of the design and some safety entries, but not a complete statistical assessment of the prespecified primary question.
9. Statistical Methods Explained
What can the design estimate?
This is a single-arm study: the registry describes one group receiving ShortCut™ and no concurrent control group. In general, a single-arm study can summarize outcomes observed in that group. It cannot estimate a randomized between-group contrast because there is no randomized comparison. A before-and-after or historical comparison would require data and methods not reported in the registry record; none should be inferred.
The design is also listed as non-randomized and open-label. Randomization is a method for assigning participants to groups by chance, which can help make groups comparable on average when a comparison is planned. Here, no allocation to different groups is described. Open-label means masking was not used, but the registry record does not describe outcome-assessor masking or adjudication procedures.
How should counts and percentages be read?
The primary endpoint is expressed as a count of participants with specified outcomes during the stated post-procedure window. Counts are direct summaries, but interpretation usually benefits from a clearly defined denominator, complete follow-up information, and rules for classifying each event. The record lists 60 participants at risk for the serious and other adverse event summaries. It does not report detailed follow-up completeness or event-level counting rules. General statistical interpretation therefore distinguishes the reported counts from a fully characterized rate or comparative estimate.
Percentages attached to serious adverse event terms are descriptive entries in the registry. The record does not specify whether an individual participant could contribute to multiple terms or give enough detail to infer how the terms relate to the overall serious-event count. A reader should not add these percentages or treat them as disjoint categories. The registry record also does not provide confidence intervals for these entries.
What does uncertainty mean?
In general, a confidence interval gives a range of values compatible with a statistical estimate under a specified method. It conveys uncertainty that a point estimate alone does not show. The registry record does not report a confidence interval for the primary endpoint or for the safety summaries described. Thus, the precision of those results cannot be evaluated from interval estimates. The absence of an interval is not evidence that the estimate is precise or imprecise; it means that this uncertainty measure is not reported.
Likewise, a p-value summarizes how compatible data are with a specified statistical hypothesis under assumptions of a test. It is not a measure of clinical importance or proof that an effect is present or absent. The registry record lists zero analyses and does not report p-values for the primary endpoint. No hypothesis test result should be inferred from the endpoint listing or the adverse-event counts.
What do the planning assumptions describe?
The registry record describes a planning illustration based on an observed effect, with a two-sided significance level of 0.05, equal allocation between two hypothetical arms, and a normal approximation. It says the effect to detect is a stated fraction of the observed effect. Such assumptions describe a planning exercise, not a result from the enrolled participants and not the design of this single-arm study. They do not establish that the trial was planned or powered using those assumptions. The record does not report the trial's own sample-size justification.
In general, sample-size calculations depend on the target effect, variability or event frequency, the statistical test, and other design assumptions. When an illustration uses a fraction of an observed effect, that exercise is conditional on the chosen target and assumptions. It is not observed power, and it does not show whether a study result is true. The record does not report an inferential analysis of the primary endpoint, so a planning illustration cannot fill that gap.
Why can over-dispersion matter?
In general, over-dispersion occurs when count data vary more than a chosen statistical model expects. If a model assumes less variability than the data contain, standard errors and interval estimates can be misleading. This concept may matter in analyses of event counts, but the registry record does not report a count model, a dispersion assessment, or an adjusted count analysis. It is therefore a general methodological consideration, not a description of a method used in this study.
What analysis details are unavailable?
The registry record does not report an analysis plan specifying estimands, model choices, covariate adjustment, confidence-interval methods, or multiplicity procedures. It also does not report a detailed definition of the analysis set, missing-data methods, sensitivity analyses, or handling of protocol deviations. Without these details and without posted endpoint results, statistical interpretation is limited to the design and descriptive safety entries that are recorded.
10. Multiplicity, Missing Data and Analysis Populations
The registry record lists 16 outcome measures, including the primary endpoint and secondary outcomes for mortality, stroke, coronary obstruction, myocardial infarction with new evidence of coronary artery obstruction requiring intervention, major vascular complications, cardiac tamponade, acute kidney injury, and access-related type 3-4 bleeding. It does not report a testing hierarchy or a multiplicity adjustment. In general, evaluating multiple outcomes can increase the chance of at least one apparently notable result arising by chance when many statistical tests are conducted. Whether and how that concern was addressed is not reported in the registry record. No analyses are listed, so there are no reported outcome p-values to interpret in relation to multiplicity.
Missing-data methods are not reported in the registry record. The record does not state how participants without an endpoint assessment were handled, whether follow-up was complete, or whether any sensitivity analysis was performed. The primary endpoint window ends at discharge or 7 days post-procedure, whichever occurs first, but the record does not describe how missing status within that window would be classified.
Analysis populations are also not reported in the registry record. Although enrollment is listed as 60 and adverse event summaries list 60 at risk, this does not establish that every enrolled participant contributed to every endpoint analysis. The registry record does not describe exclusions, withdrawals, protocol deviations, or the denominator used for the primary endpoint. These missing details limit assessment of completeness and potential bias in the reported safety information.
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 |
|---|---|---|---|
| ShortCut™ | 13 | 60 | 21.7% |
Deaths
| Arm | Deaths (participants affected of at risk) |
|---|---|
| ShortCut™ | 3 of 60 |
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 |
|---|---|
| ShortCut™ | 5 of 60 |
Most frequent serious adverse event terms
| Event term | Organ system | ShortCut™ |
|---|---|---|
| Permanent pacemaker | Cardiac disorders | 6 of 60 |
| Coronary obstruction | Cardiac disorders | 3 of 60 |
| Myocardial Infarction with new evidence of coronary artery obstruction requiring intervention | Cardiac disorders | 2 of 60 |
| Acute kidney injury stage 3-4 | Renal and urinary disorders | 2 of 60 |
| All-cause stroke | Nervous system disorders | 1 of 60 |
| Cardiac tamponade | Cardiac disorders | 1 of 60 |
Most frequent non-serious adverse event terms
| Event term | Organ system | ShortCut™ |
|---|---|---|
| Left Bundle Branch Block (LBBB) | Cardiac disorders | 5 of 60 |
Serious events with the highest arm-level rate: permanent pacemaker (10.0%), coronary obstruction (5.0%), myocardial infarction with new evidence of coronary artery obstruction requiring intervention (3.3%), acute kidney injury stage 3-4 (3.3%), all-cause stroke (1.7%).
The safety entries list 13 participants with serious adverse events and 5 participants with other adverse events, with 60 at risk for each summary. The record separately lists 3 deaths. Among the leading serious adverse event terms, it reports permanent pacemaker at 10.0%, coronary obstruction at 5.0%, myocardial infarction with new evidence of coronary artery obstruction requiring intervention at 3.3%, acute kidney injury stage 3-4 at 3.3%, all-cause stroke at 1.7%, and cardiac tamponade at 1.7%.
These entries should be read as descriptive safety information from a single-arm study. The registry record does not report whether participants could have more than one serious adverse event term, how events were adjudicated, or how the listed terms relate to the overall counts. The entries therefore should not be summed or treated as mutually exclusive. The record also does not provide comparative safety estimates, confidence intervals, or a full account of follow-up and analysis populations. These figures describe reported events; by themselves, they do not establish whether an event was caused by the device or procedure, or how risk compares with another approach.
12. What the Result Does, and Does Not, Mean
The registry record establishes that a prospective, multicenter, non-randomized, single-arm, open-label study of ShortCut™ was completed, with enrollment listed as 60. It identifies the clinical setting as ViV TAVR among patients at risk of TAVR-induced coronary artery ostium obstruction. It also records some safety counts and serious adverse event terms. These details describe the study and the events entered in the registry.
The record does not report the result for the primary endpoint of device- and/or procedure-related mortality and all-cause stroke by discharge or 7 days post-procedure, whichever occurred first. It also lists zero analyses. Accordingly, the primary safety outcome cannot be quantified or assessed for precision using the registry record. The study's stated aim to demonstrate safety and effectiveness is not itself evidence that either was demonstrated.
Because there is no control arm, the reported events cannot be compared directly with outcomes under another treatment or procedure in this study. Even a complete count of outcomes in the ShortCut™ group would describe what happened in that group, not what would have happened to comparable participants under a different approach. The design therefore does not support a randomized causal comparison.
The safety terms are useful as a record of reported events, but definitions, overlap between categories, follow-up completeness, and event attribution are not detailed. The record also does not describe analysis populations or missing-data handling. These gaps mean that readers should avoid interpreting descriptive safety entries as a comprehensive comparative risk assessment.
In general, registry results are most informative when endpoint estimates, uncertainty measures, analysis methods, and participant disposition are reported alongside design details. Those elements are not available for the primary outcome in this record. The reasonable statistical conclusion is limited: the record describes the study and selected safety findings, but does not report enough primary-outcome analysis to establish the magnitude or precision of that outcome, or to support a comparative claim.
13. Why This Trial Matters Statistically
This study addresses a specific procedural concern recorded in the registry: risk of coronary obstruction following TAVR, in the setting of ViV procedures. The design and the primary endpoint show how the investigators framed the safety question: they recorded mortality related to the device and/or procedure together with all-cause stroke during an early post-procedure period. The safety listings also include coronary obstruction and other serious event terms relevant to the stated clinical context.
Statistically, the study is a useful example of the distinction between describing outcomes and estimating comparative effects. A single-arm study can document what was reported among participants receiving a device, but cannot supply a concurrent control comparison. That distinction matters when readers interpret safety counts, especially when background procedural risks and participant characteristics may also be relevant. No such comparison is reported.
The record also demonstrates why endpoint results and uncertainty measures matter. It lists enrollment and safety events, but does not report the primary endpoint result or statistical analyses. Without an endpoint estimate, its precision, or a comparison, the stated study aim cannot be evaluated statistically from the record. Completion status alone does not answer the clinical question.
Finally, the registry lists multiple outcomes but does not report how testing across outcomes was handled, how missing observations were treated, or which participants were included in each analysis. Those details affect how results can be interpreted when analyses are available. Their absence, together with the missing primary result, means that the strongest defensible reading is a description of study design and recorded safety events rather than a conclusion about comparative safety or effectiveness.
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.
Several limitations are specific to the information recorded for this study. First, it is a single-arm, non-randomized design with no concurrent control group. That prevents direct estimation of differences versus another procedure or device from this study alone. Open-label conduct is recorded, but the registry record does not report whether outcome assessors were masked or whether events were independently adjudicated.
Second, the registry lists the study as completed but does not report the primary endpoint result or any statistical analyses. The primary endpoint's description and time window are present, but its operational definitions, event attribution process, and rules for participants experiencing more than one component are not reported in the registry record. This leaves the principal study question unanswered by the posted results.
Third, enrollment is listed as 60, and the serious and other adverse event summaries each list 60 at risk, but participant disposition and endpoint-specific analysis populations are not described. The registry record does not report withdrawals, missing assessments, follow-up completeness, or how missing outcomes were handled. It also does not provide detailed baseline characteristics or full eligibility criteria, limiting assessment of the population represented.
Finally, the record lists multiple outcome measures without reporting a testing hierarchy, multiplicity adjustment, analysis plan, or uncertainty estimates. The adverse-event entries do not explain overlap among terms or their relationship to overall participant counts. These reporting gaps limit both reproducibility and precision of interpretation. They do not establish that unreported methods were absent from the study; they mean that those methods and results are not reported in the registry record.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: The ShortCut™ Study Protocol — NCT04952909.
- Registry record last updated 2025-02-03; status last verified 2023-08.
- Results first posted 2025-02-03.
- 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
NCT04952909 is a completed, prospective, multicenter, non-randomized, single-arm, open-label study of the ShortCut™ device. The registry lists enrollment of 60, a start date of 2022-01-21, and a primary completion date of 2023-09-30. The stated clinical setting is ViV TAVR among patients at risk of TAVR-induced coronary artery ostium obstruction.
The primary endpoint is a participant count for ShortCut™ device- and/or procedure-related mortality and all-cause stroke by discharge or 7 days post-procedure, whichever occurs first. Its result and statistical analyses are not reported in the registry record. Safety entries include 13 participants with serious adverse events, 5 with other adverse events, and 3 deaths; selected serious adverse event terms are listed with percentages. With no control arm, these findings are descriptive rather than comparative. Missing analysis details and the absent primary result limit assessment of the study's main statistical question.