Shockwave Coronary Rx Lithoplasty® Study (Disrupt CAD I): Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Shockwave Coronary Rx Lithoplasty® Study (Disrupt CAD I) (NCT02650128), a na na study. The primary outcome is Safety - Frequency of Major Adverse Cardiac Events (MACE) Within 30 Days of the Procedure..

2. Clinical Question

Disrupt CAD I was designed to evaluate the safety and performance of the Shockwave Coronary Rx Lithoplasty® System in people with calcified lesions in the coronary arteries. The clinical question was whether use of the system before stent placement could support stent placement and reduce residual stenosis, while also assessing safety. The registry identifies major adverse cardiac events (MACE) within 30 days of the procedure as the primary endpoint.

The study used a single group receiving the device; it did not include a randomized control group. Therefore, its design can describe outcomes among participants treated in the study, but cannot directly compare those outcomes with outcomes under another treatment or with no use of the device. The registry lists quantitative assessment of residual stenosis in treated lesions and 180-day MACE as secondary outcomes, but does not report their observed results in the record.

The device is described as a lithotripsy-enhanced, low-pressure balloon dilation of calcified, stenotic de novo coronary arteries before stent placement. The registry’s stated purpose was to enhance stent placement and reduce ultimate residual stenosis. Those aims describe the rationale for the study; they do not establish that either goal was achieved.

The record reports enrollment of 60 and defines the analysis population as the Intent-To-Treat (ITT) set: subjects for whom insertion of the Lithoplasty catheter was attempted, with the attempt defined as the point of enrollment. However, the observed 30-day MACE count is not reported in the registry record. Consequently, the posted information does not answer how often the primary endpoint occurred in the study population. It also does not establish how the device’s outcomes compare with any alternative approach.

3. Trial Design

Disrupt CAD I is a prospective, multi-center, single-arm study of the Shockwave Coronary Rx Lithoplasty® System in coronary arteries. The registry classifies its allocation and phase as not applicable and its masking as none. Enrollment was 60. The study status is completed; the recorded start is 2015-12 and primary completion is 2016-09.

The device was used for calcified lesions in the coronary arteries. The arm description specifies lithotripsy-enhanced, low-pressure balloon dilation of calcified, stenotic de novo coronary arteries before stent placement. The brief summary says participants were followed through discharge and at 30 and 180 days. The primary endpoint concerns MACE within 30 days of the procedure. Secondary outcomes include quantitative assessment of residual stenosis in treated lesions and 180-day MACE.

Because all participants were assigned to a single group and there was no control arm, the study is not a randomized comparison. Outcomes in the device group can be described, but the design does not provide a concurrent group for estimating what would have happened under another treatment. Differences from outcomes in other settings cannot be attributed to the device using this design alone.

The record states that the ITT analysis set included subjects who had insertion of the Lithoplasty catheter attempted, defined as the point of enrollment. It also states that the primary analyses used no imputation or adjustment for missing data. Further details of the protocol, the sample-size justification, interim analyses, and a fuller statistical analysis plan are not reported in the registry record. The number of outcome measures is listed as 4, while the registry lists no analyses. The observed primary endpoint result is 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: No imputation of or adjustments for missing data were performed for the primary analyses. The population for all analysis was the Intent-To-Treat (ITT) analysis set. ITT was defined as those subjects who had insertion of the Lithoplasty catheter attempted, defined as the point of enrollment.

5. Baseline Characteristics

The table reproduces the baseline characteristics posted in the registry, which describe the participants analysed at baseline and help show whether the randomized groups were comparable.

6. Primary Endpoint

The registry lists the primary outcome as Safety - Frequency of Major Adverse Cardiac Events (MACE) Within 30 Days of the Procedure., measured over 30 days.

The primary endpoint is the frequency of major adverse cardiac events within 30 days of the procedure, reported as a number of events. The registry defines MACE as cardiac death, myocardial infarction, or target-vessel revascularization (TVR). Myocardial infarction is defined as a CK-MB level > 3 times the upper limit of the laboratory normal value, with or without a new pathologic Q wave. TVR is revascularization at the target vessel, including the target lesion, after completion of the index procedure.

A composite endpoint combines multiple clinical events into a single outcome measure. In general, such an endpoint can capture several kinds of clinically important events rather than focusing on just one. Its interpretation depends on the events included and on how each event is defined. Here, the record specifies the components and their definitions, but does not report the observed primary endpoint count.

The endpoint is framed as a safety measure in this study. Reporting a count can describe the number of recorded events, but the record does not provide a result for that count or an analysis estimating its precision. The study’s single-group design also means the endpoint cannot establish a comparative effect against a control group. Thus the endpoint definition is available, while the observed frequency and any comparative interpretation are not reported in the registry record.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

The methods information identifies a prospective, multi-center, single-arm study and describes the primary endpoint as a number of MACE events within 30 days. It also defines the ITT analysis population and states that the primary analyses did not impute or adjust for missing data. These details describe the intended endpoint and analysis population, but the observed primary endpoint count and statistical analysis are not reported in the registry record.

What does a count endpoint describe?

A count records how many events occurred, according to the endpoint definition and within its stated timeframe. The registry defines the primary measure as MACE within 30 days and lists cardiac death, myocardial infarction, and TVR as components. For interpretation, it matters that the components are specified: the myocardial infarction definition uses a CK-MB threshold of > 3 times the upper limit of laboratory normal, with or without a new pathologic Q wave, while TVR is revascularization at the target vessel, including the target lesion, after completion of the index procedure.

General statistical context: a composite outcome combines different event types. The combined count is meaningful only in relation to the precise component definitions and the way events are counted. The registry record does not report a component-by-component result for the primary endpoint, nor does it report the overall MACE count. The term “frequency” in the endpoint title does not, on its own, supply an observed frequency.

What does the single-group design allow?

The study has one device group and no randomized comparator. General statistical context: a single-group study can describe outcomes in the participants who received the intervention. A concurrent comparison group is needed to make a direct comparison within the trial. Without one, the observed outcomes cannot establish whether the device changed event frequency relative to another strategy. Other influences on outcomes cannot be separated from the intervention using this design alone.

The registry does not list an allocation procedure for assigning participants to different groups, which is consistent with the recorded single-group model. It lists masking as none. The record does not report a blinded outcome assessment process or additional details that would explain how the outcome definitions were applied in practice. Such procedural details should not be inferred from the design label.

Who was included in the analysis population?

The registry defines the ITT analysis set as subjects who had insertion of the Lithoplasty catheter attempted, with the attempt defined as the point of enrollment. This definition makes attempted insertion the stated criterion for inclusion in the analysis population. The registry also says there was no imputation of or adjustment for missing data in the primary analyses. The number and pattern of missing observations, and the handling of any specific incomplete records beyond that statement, are not reported in the registry record.

General statistical context: imputation is a way of filling in missing values using an explicit statistical method. When missing information is not imputed, an analysis may rely on the observations available under its stated inclusion rules. Missingness can affect how representative those observations are, depending on why information is absent. The registry statement does not establish whether missing data occurred, how much there may have been, or whether missingness could affect the results.

What can be said about uncertainty and statistical testing?

A confidence interval is a statistical range used to express uncertainty around an estimate. A hypothesis test evaluates data against a specified null hypothesis under a stated analysis plan. Neither a confidence interval nor a primary endpoint test result is reported in the registry record. The record lists no analyses, so no reported statistical test or estimate can be interpreted. The absence of an analysis entry should not be mistaken for a finding of no events or no effect.

General statistical context: event counts can be sparse, and the uncertainty around a count-based estimate can be substantial when few events occur. The amount of uncertainty cannot be assessed without the observed result and a defined estimation method. The registry’s endpoint is a count, but no method details for estimating uncertainty are reported. Any further assumptions about a model, adjustment, or test would go beyond the record.

What is and is not a trial design assumption?

The record describes separate planning illustrations based on a stated fraction of an observed effect, with a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation. It specifies that non-time-to-event illustrations are participants per arm and time-to-event illustrations are total event counts. These are planning assumptions, not the design of this single-arm study and not observed trial results. No planning illustration should be read as observed power or as proof of an effect. The registry’s own sample-size justification is not reported in the registry record.

In general, over-dispersion occurs when count variability is greater than a statistical model assumes; ignoring it can make uncertainty appear too small. The registry record does not report a count model or evidence about over-dispersion, so this issue cannot be evaluated for the primary outcome. More broadly, the available methods information is limited to the design, endpoint definition, analysis-population definition, and missing-data statement. The observed endpoint results and the fuller analysis choices are not reported in the registry record.

10. Multiplicity, Missing Data and Analysis Populations

The registry lists 4 outcome measures, including the primary safety endpoint and secondary outcomes of quantitative assessment of residual stenosis in treated lesions and 180-day MACE. It does not report how statistical testing across outcomes was planned or whether any adjustment for multiple testing was used. The number and nature of interim analyses are not reported in the registry record. The record lists no analyses, so it provides no inferential results from which to assess how multiple outcomes were handled.

General statistical context: when several outcomes or comparisons are tested, the chance of at least one apparently unusual result can increase if each is assessed separately without an adjustment. A multiplicity strategy can define which outcomes are confirmatory and how testing is controlled. No such strategy is reported, so no claim about multiplicity control is warranted.

For the primary analyses, the record states that no imputation of or adjustments for missing data were performed. It does not report the amount of missing information, the reasons for missingness, or any sensitivity analysis evaluating how missing observations might affect the endpoint. General statistical context: missing-data methods can influence estimates when available observations differ systematically from those not observed. The registry statement alone does not establish whether missing data occurred or whether it materially affected any result.

The ITT population is defined as subjects for whom insertion of the Lithoplasty catheter was attempted, with that attempt identified as the point of enrollment. This is the stated analysis-population rule. Further details about exclusions, deviations, or additional analysis populations are not reported in the registry record. The observed primary endpoint result and its analysis are not reported either, limiting assessment of both the endpoint and the methods used to handle multiplicity or incomplete data.

11. 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: coronary artery dissection (5.0%), anaemia (1.7%), angina unstable (1.7%), sinus bradycardia (1.7%), upper gastrointestinal haemorrhage (1.7%).

The adverse-event record lists 10 participants affected by serious adverse events among 60 at risk and 37 affected by other adverse events among 60 at risk in the Shockwave Coronary Rx Lithoplasty System group. It also lists 2 deaths. The registry identifies Coronary Artery Dissection at 5.0% as the most frequently listed serious adverse event term, followed by Anaemia, Angina Unstable, Sinus Bradycardia, Upper Gastrointestinal Haemorrhage, and Cellulitis, each at 1.7%.

These entries describe the adverse-event information recorded for the single study group. They are not a randomized comparison and do not establish whether an event was caused by the device. The available record does not clarify whether participants could appear in more than one event category or whether the listed deaths occurred within the primary endpoint timeframe. The serious adverse-event figures must therefore be read separately from the primary MACE outcome, whose observed result is not reported in the registry record.

General statistical context: adverse-event counts and term percentages describe what was recorded under the registry’s reporting conventions. They do not, by themselves, establish comparative risk or causation. Interpretation also depends on definitions, follow-up, and how events were collected. Details beyond the figures and terms listed are not reported in the registry record.

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

The record provides a description of a completed, prospective, multi-center, single-arm device study, its target population, intervention, follow-up schedule, and endpoint definitions. It establishes that the primary safety endpoint was MACE within 30 days and that MACE included cardiac death, myocardial infarction under a specified CK-MB definition, and TVR under a specified revascularization definition. It also reports adverse-event entries for the device group.

What the record does not provide is the observed count for the primary endpoint. It therefore does not show how many MACE events occurred during the stated timeframe or how precisely that count was estimated. The registry also does not report the observed results for residual stenosis or 180-day MACE. The outcome measures’ presence in the record should not be mistaken for reported results.

The study’s aims were to evaluate safety and performance, enhance stent placement, and reduce ultimate residual stenosis. A study aim is not evidence that the intended outcome was achieved. Without a reported primary result, the registry information does not support a conclusion about the frequency of 30-day MACE in the study. Without a concurrent control group, even a reported outcome count would describe the enrolled group rather than establish a comparative effect attributable to the device.

The adverse-event figures and listed terms are useful descriptions of the recorded safety information, but they do not resolve the missing primary endpoint result. The record does not establish causal attribution for those events, and the entries should not be interpreted as a comparison with another treatment. It also does not report the relationship between the deaths and the MACE definition or timeframe.

In general, statistical interpretation requires both an estimate and information about its uncertainty, alongside an understanding of the design that produced it. Here, the primary estimate and its precision are not reported. The appropriate reading is consequently limited: the registry documents what the study set out to assess and some adverse-event information, but it does not report the primary outcome needed to quantify the study’s main safety result or establish a treatment effect.

13. Why This Trial Matters Statistically

This trial is statistically notable for the gap between a clearly stated endpoint definition and the absence of a reported primary endpoint result in the registry record. The endpoint is specified as a count of MACE within 30 days, with component definitions for cardiac death, myocardial infarction, and TVR. Those details make the intended measure interpretable in principle. Without the observed count, however, the endpoint cannot be quantified from the registry information, and its precision cannot be assessed.

The single-arm design is also important. It can describe outcomes among participants who received the device, but it cannot supply a randomized, concurrent comparison. This distinction separates descriptive safety reporting from evidence about comparative effects. Any conclusions about what would have happened under another approach would require information not posted by this design alone.

The registry records 60 enrolled participants and defines the ITT population by attempted catheter insertion. It also states that no imputation or adjustment for missing data was performed in the primary analyses. These details matter because population definitions and missing-data handling shape what an analysis represents. Yet the record does not report the primary analysis, the result, or the amount of missing information, so the practical consequences of these choices cannot be assessed.

The adverse-event entries show why endpoint definitions and reporting categories should be kept distinct. Serious adverse events, other adverse events, deaths, and the MACE composite are not automatically interchangeable summaries. The record does not establish their overlap or align all of them to the primary endpoint timeframe.

General statistical context: a study’s evidential value depends not only on the question it asks, but also on the information reported about estimates, uncertainty, and analysis. In this case, the design and definitions are recorded, while the main endpoint result and its statistical analysis are not. That makes careful separation of documented details, study aims, and unavailable results especially important.

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 for interpreting the study from the registry record is that the observed 30-day MACE result is not reported. The outcome is defined, but its count and any measure of uncertainty are absent. The record also does not report observed results for the listed secondary outcomes of residual stenosis and 180-day MACE. This prevents a quantitative assessment of the study’s principal safety measure and stated secondary measures.

The single-arm design has no randomized control group, so it does not provide a direct within-study comparison. It cannot establish whether observed outcomes differ from those under another strategy. The record does not report enough information to make causal attribution for adverse events or deaths.

The adverse-event listing has limited contextual detail in the registry information described. It does not establish whether individuals could be represented in more than one category, whether deaths corresponded to the primary endpoint definition, or whether those deaths fell within the 30-day period. The record also does not report detailed event ascertainment procedures or outcome adjudication.

The registry states that no imputation or adjustment for missing data was performed for the primary analyses, but does not report the amount or pattern of missing data or sensitivity analyses. The full statistical analysis plan, sample-size justification, and interim-analysis details are not reported in the registry record. These limitations concern what can be interpreted from the record; they do not establish that any unreported analysis or procedure did or did not occur outside it.

15. Related Tutorials

16. Related Statistical Calculators

17. Sources

• ClinicalTrials.gov: Shockwave Coronary Rx Lithoplasty® Study (Disrupt CAD I) — NCT02650128.
• Registry record last updated 2018-11-02; status last verified 2018-03.
• Results first posted 2018-11-02.
• 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

Disrupt CAD I is a completed, prospective, multi-center, single-arm study of the Shockwave Coronary Rx Lithoplasty® System for calcified coronary lesions. Enrollment was 60. The primary endpoint was the frequency of MACE within 30 days, defined to include cardiac death, myocardial infarction under the registry’s CK-MB criterion, and target-vessel revascularization after the index procedure.

The registry defines the ITT population by attempted catheter insertion and states that no imputation or adjustment for missing data was performed for the primary analyses. It lists secondary outcomes of residual stenosis and 180-day MACE. The adverse-event record lists 10 participants affected by serious adverse events, 37 by other adverse events, and 2 deaths among the group’s 60 at risk. The observed primary endpoint result and the results for the secondary outcomes are not reported in the registry record. The single-arm design does not provide a randomized comparator.