Efficacy of Everolimus-Eluting Versus Zotarolimus-Eluting Sten for Coronary Lesions in Acute Myocardial Infarction: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Efficacy of Everolimus-Eluting Versus Zotarolimus-Eluting Sten for Coronary Lesions in Acute Myocardial Infarction (NCT01347554), a randomized phase 4 study. The primary outcome is Device-oriented Composite Outcome.

2. Clinical Question

The comparison addresses outcomes after stent insertion in acute myocardial infarction, a clinical setting identified in the registry rationale as distinct from the selected lesions studied in some earlier trials. The trial is recorded as randomized, with a parallel-group design and no masking. The registry record does not report the method used to generate or conceal the allocation sequence, nor does it describe whether outcome assessment was blinded.

The primary result is a comparison of recorded event counts and risks in the two randomized groups. It is not, by itself, a complete account of each component of the composite or of all possible benefits and harms. Component-specific primary outcome counts, eligibility details, and the number of participants with complete follow-up are not reported in the registry record. The findings therefore need to be read in the context of the outcome definition and the reporting detail available.

3. Trial Design

The registry record describes a phase 4, randomized, open-label, parallel-group trial comparing two drug-eluting stents in people with acute myocardial infarction. The two arms were the Xience V everolimus-eluting stent group and the Endeavor Resolute zotarolimus-eluting stent group. Enrollment was 461: 230 participants were listed in the Xience V group and 231 in the Endeavor Resolute group.

The trial began in 2009-01, had a primary completion date of 2013-03, and is recorded as completed. Yonsei University is listed as the sponsor. The registry record lists the primary endpoint timeframe as two years. Several secondary outcomes are also specified, including stent thrombosis and any bleeding, with their timeframes recorded as two years or two year.

Randomization supports a planned comparison of groups, but the record does not describe the allocation sequence, allocation concealment, stratification, or other design details. Masking is listed as none. The record does not say whether people assessing outcomes were masked, or whether the analysis was conducted according to the original randomized assignments.

The registry record does not report the original sample-size justification, target effect used in planning, expected event rates, or design assumptions. It also does not give a detailed participant flow, numbers lost to follow-up, or reasons for missing outcome data. Consequently, the posted enrollment and arm counts describe the listed trial population but do not establish how many participants contributed complete data to each endpoint.

The record lists no reported statistical analyses. It therefore does not document a prespecified primary analysis model, covariate adjustment, approach to missing data, or method for handling multiple outcomes. These omissions limit the extent to which the posted comparisons can be checked against a full protocol-level analysis plan.

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 with acute myocardial infarction were eligible if they had at least one lesion with a diameter stenosis of 50%or more. Before randomization, 3 patients withdrew consent and 18 patients did not meet inclusion criteria among 500 patients.

Overall Study

Reasons for not completing this period:

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 Device-oriented Composite Outcome, measured over Two year.

The primary endpoint is the device-oriented composite outcome, measured as the number of participants with an event by two years. The registry defines it as a composite of cardiac death, myocardial infarction not clearly attributable to a nontarget vessel, and target lesion revascularization. A participant meeting any included component can contribute to the composite outcome; the record does not provide the primary result broken down by component.

Composite endpoints are used in clinical trials to capture more than one clinically relevant event within a single outcome. In general, combining events can provide a broader summary of outcomes and may produce more events for analysis than considering a less frequent component alone. However, the components may differ in clinical importance, frequency, and interpretation. A composite result does not show whether the groups had similar patterns for each component, and a difference in the overall composite could be driven mainly by one component.

The endpoint is relevant to a comparison of coronary stents because its definition includes events related to cardiac outcomes and treatment of the target lesion. That rationale does not establish that every component reflects the same underlying process or has the same weight in interpretation. The registry record does not report component-specific results, a rationale for the composite construction, or details on how events were adjudicated.

The primary outcome counts are recorded as 12 participants in the Xience V group and 13 in the Endeavor Resolute group. A separate secondary outcome entry with the same device-oriented composite title records 20 and 24 participants, respectively, at a timeframe of two years. The registry record does not explain why these two entries differ, so they should be treated as separate posted entries rather than reconciled by assumption.

7. Results Posted in the Registry

• Endeavor Resolute Group: 5.6% (13/231) versus 5.2% (12/230) on control; risk difference 0.4 percentage points (95% CI -3.7 to 4.5), risk ratio 1.08 (0.50–2.31); unadjusted two-proportion z-test p = 0.846.

8. Secondary Efficacy Endpoints

The registry also posts results for secondary outcomes. For each outcome below, the endpoint type, the test applied to the posted summary statistics, the result and its interpretation are given in turn. Secondary endpoints are usually not adjusted for multiple testing, so they support rather than confirm the primary finding.

Device-oriented Composite Outcome

• Endpoint type: Binary: the number of participants with the event, compared as proportions.
• Test: Unadjusted two-proportion z-test, with a Wald 95% confidence interval for the risk difference.
• Result:
  • Endeavor Resolute Group: 10.4% (24/231) versus 8.7% (20/230) on control; risk difference 1.7 percentage points (95% CI -3.7 to 7.1), risk ratio 1.19 (0.68–2.10); unadjusted two-proportion z-test p = 0.536.
• Interpretation:
  • The 95% confidence interval includes no difference, so these data do not show a statistically significant difference between Endeavor Resolute Group and the control. The interval gives the range of effects that remain compatible with the data.

Stent Thrombosis

• Endpoint type: Binary: the number of participants with the event, compared as proportions.
• Test: Unadjusted two-proportion z-test, with a Wald 95% confidence interval for the risk difference.
• Result:
  • Endeavor Resolute Group: 3.0% (7/231) versus 0.0% (0/230) on control; risk difference 3.0 percentage points (95% CI 0.8 to 5.2); unadjusted two-proportion z-test p = 0.008.
• Interpretation:
  • The 95% confidence interval excludes no difference, so the proportion with the event is statistically higher for Endeavor Resolute Group than for the control. This is an unadjusted, secondary comparison, so it is suggestive rather than confirmatory.

Any Bleeding

• Endpoint type: Binary: the number of participants with the event, compared as proportions.
• Test: Unadjusted two-proportion z-test, with a Wald 95% confidence interval for the risk difference.
• Result:
  • Endeavor Resolute Group: 4.8% (11/231) versus 3.0% (7/230) on control; risk difference 1.7 percentage points (95% CI -1.8 to 5.2), risk ratio 1.56 (0.62–3.97); unadjusted two-proportion z-test p = 0.341.
• Interpretation:
  • The 95% confidence interval includes no difference, so these data do not show a statistically significant difference between Endeavor Resolute Group and the control. The interval gives the range of effects that remain compatible with the data.

The secondary outcome pattern is mixed. The device-oriented composite entry listed as secondary has counts in both groups and a positive estimated risk difference, while the stent thrombosis comparison records events only in the Endeavor Resolute group. Any bleeding also has a positive point estimate. These outcomes are not interchangeable: they describe different event types, and the composite combines several components.

The secondary composite has the same title as the designated primary outcome but different posted counts. The registry record does not explain the difference. It is important not to merge the entries or use one to overwrite the other. The primary interpretation remains tied to the entry designated as primary, while the separate secondary entry contributes to the broader pattern of reported outcomes but raises a question about the record's endpoint reporting.

In relation to the primary result, the secondary estimates do not provide a uniform pattern across outcomes. The primary risk difference is close to zero with an interval that includes zero. The stent thrombosis result is the one secondary comparison with a reported unadjusted p-value below 0.05, whereas the bleeding comparison has an interval including zero. This contrast does not establish a definitive overall difference between devices: each endpoint has its own uncertainty, and different outcomes may reflect distinct aspects of follow-up.

Unadjusted secondary results carry less weight because multiple outcomes are posted and the registry does not report a multiplicity strategy, endpoint hierarchy, or confirmatory analysis plan. In general, examining multiple outcomes increases the opportunity for chance findings, especially when each is interpreted in isolation. The secondary results are therefore useful as descriptive signals in the posted data, but should not be treated as independent confirmation of the primary finding or as a complete safety assessment.

Component-level results for the primary composite, detailed event definitions for the secondary endpoints, and procedures for event adjudication are not reported in the registry record. These omissions limit direct comparison across endpoints and make it harder to determine how consistently outcomes were ascertained.

Secondary outcomes registered for this trial, for reference (only those above were recalculated):

• Device-oriented Composite Outcome
• Stent Thrombosis
• Any Bleeding

9. Statistical Interpretation

10. Statistical Methods Explained

The posted comparisons use binary outcomes: each participant is classified according to whether an event was recorded. The primary and secondary outcomes are reported as participant counts in each group, with risks and risk differences in the pairwise comparisons. The registry record lists no reported analyses, so the displayed unadjusted comparisons should not be assumed to represent a fully documented prespecified statistical plan.

What does a risk difference express?

In general, a risk difference subtracts the event risk in one group from the risk in the other group. Its sign depends on the order of comparison. Here, the comparison is framed as Endeavor Resolute relative to Xience V, so a positive estimate corresponds to a higher posted event risk in the Endeavor Resolute group. A risk difference is expressed on an absolute scale, which makes it possible to describe how far apart the two observed risks are without converting the result into a relative measure.

The point estimate is only one summary of the comparison. It reflects the observed group risks, but it does not by itself indicate how precisely the underlying difference has been estimated. The confidence interval gives a range of values compatible with the data under the method used, subject to the assumptions of that method. A wide interval can include effects in opposing directions, making the point estimate less conclusive than it may appear on its own.

What does the p-value contribute?

In general, a p-value describes how unusual data at least as incompatible with a specified null hypothesis would be if that hypothesis and the test assumptions held. It is not the probability that the null hypothesis is true, nor is it a measure of clinical importance. The registry comparisons label the p-values as unadjusted. The record does not report the specific testing procedure, whether the test was prespecified, or whether the reported values account for other outcomes or analyses.

For the primary endpoint, the unadjusted p-value is 0.846. This value does not establish that the groups are identical. Rather, the primary estimate and confidence interval show that the posted data are compatible with a range of possible risk differences. Evidence for equivalence would require an explicit equivalence margin and an analysis designed to evaluate that margin; these details are not reported in the registry record.

Why are event counts important?

Binary outcome estimates depend on the number of participants who experience the event and the number assessed in each group. When event counts are limited, estimates may be imprecise, and a small change in the recorded count can have a noticeable effect on the comparison. In general, sparse data can also make some statistical methods less reliable, particularly methods relying on large-sample approximations. The registry record does not state which method was used to calculate the confidence intervals or p-values, so the specific approximation cannot be assessed.

The Xience V arm has zero recorded participants with stent thrombosis, while the Endeavor Resolute arm has seven. A zero count in one group makes some relative measures difficult or impossible to estimate using ordinary methods, which is one reason the posted comparison is expressed as a risk difference. The registry does not provide a relative risk or odds ratio for this endpoint. No method-specific details are reported, and no further inference should be made from the choice of measure alone.

What does randomization contribute?

In general, random allocation is intended to make comparison groups similar on average with respect to measured and unmeasured characteristics at the time of assignment. It does not guarantee balance in every trial, and it does not remove the need for clear follow-up and analysis methods. In an open-label trial, participants and clinical teams know the assigned device, which can potentially influence care or assessment. Whether that occurred in this trial cannot be determined from the registry record. The record does not report blinded outcome assessment or event adjudication.

A complete interpretation also depends on analysis population and missing data. An intention-to-treat analysis generally retains participants in their randomized groups, while other analysis populations may impose additional conditions. The registry record does not state which population was used. It also does not report how incomplete follow-up or missing endpoint values were handled. These omissions matter because the number analyzed and the way missing outcomes are treated can affect estimates.

The multiple posted outcomes raise another general methodological issue. Testing several endpoints can increase the chance of seeing an apparently notable result by chance if each is treated as a separate confirmatory test. Statistical plans can address this through prespecified hierarchies or adjustments, but neither is described in the registry record. The secondary p-values are therefore best read as unadjusted comparisons, not as a complete multiplicity-controlled confirmatory analysis.

Finally, the registry contains two entries with the device-oriented composite outcome title. One is designated primary and records 12 and 13 events; the other is listed among secondary outcomes and records 20 and 24. The record does not explain the difference. This is a reporting ambiguity rather than a statistical problem that can be resolved from the posted entries alone.

11. Confidence Intervals and Precision

The primary risk difference is 0.004, and its 95% confidence interval runs from -0.037 to 0.045. The interval includes zero and extends in both directions. In general, a confidence interval summarizes the uncertainty in an estimate under the statistical method and assumptions used; it is not a guarantee that the true effect lies within the interval. Its width is relevant to precision: a broader range leaves more uncertainty about the size and direction of the difference.

The point estimate alone is not a sufficient description. Although the observed risks are close, the interval is compatible with a negative risk difference as well as a positive one. The posted data therefore do not pin down the direction or magnitude with high precision. The interval and the unadjusted p-value of 0.846 tell related but different parts of the statistical story: the interval gives a range of estimates compatible with the data, while the p-value describes the data relative to a specified null under a test.

The registry record does not identify the confidence-interval method or provide a prespecified threshold for a difference considered clinically important. Without such a threshold, statistical precision cannot be translated into a judgment about whether all values in the interval would matter clinically. Nor can the interval be used to establish equivalence or noninferiority without an appropriate design and margin.

Precision is also constrained by the available outcome counts and reporting detail. The record does not report how many participants completed follow-up or how missing outcomes were handled. In addition, the same composite outcome appears in a separate secondary entry with different counts, and the reason is not reported in the registry record. That ambiguity affects confidence in how the endpoint entries should be understood, even though it does not change the primary comparison as listed.

12. Planning a Similar Trial: Sample Size

This is a planning illustration, not a re-evaluation of the original trial. It asks: if a new study wanted to detect a difference like the one observed, or a smaller one, how large would it need to be? It is deliberately not “observed power” of the finished trial, which is not a meaningful quantity.

The planning figures are participants per arm for these binary outcomes. The general planning assumptions are a two-sided significance level of 0.05, equal allocation between the two arms, and a normal approximation. The assumed effect to detect is a stated fraction of the observed effect. The trial's own original sample-size assumptions and justification are not reported in the registry record.

The 80% power column represents the planned number of participants per arm for a hypothetical study to have an 80% probability of detecting the assumed effect under the stated assumptions, if that effect and the model assumptions were correct. The 90% power column uses a higher target probability of detection under the same general framework. These are planning illustrations, not estimates of the trial's achieved power.

The rows consider planning for 100%, 75%, and 50% of the observed effect. A smaller effect is harder to distinguish from random variation, so detecting a smaller effect generally requires more participants. The figures should be read as conditional planning scenarios based on the observed effect, rather than as evidence that the original trial was designed around those effects. They do not report the number actually enrolled for each hypothetical scenario.

For time-to-event outcomes, the stated planning convention would be total events, but the outcomes discussed in these comparisons are binary participant counts, so the figures are participants per arm. The associated planning curve represents the same general relationship: as the effect selected for detection becomes smaller, the required sample size increases. These illustrations do not account for unreported features such as loss to follow-up, missing outcomes, or an analysis adjustment.

13. How the Sample Size Is Derived

Power is the probability that a study of a given size rejects the null hypothesis when a specific true effect exists. It depends on four things: the effect to detect, the variability of the outcome, the significance level (here a two-sided α of 0.05, so z_1−α/2 = 1.960) and the desired power (z_1−β = 0.842 for 80% and 1.282 for 90%).

Formula

n is the number of participants in each arm, p₀ and p₁ are the control and treatment proportions, and p̄ is their average.

Worked calculation for this trial

1. Control proportion p₀ = 0.052; treatment proportion p₁ = 0.056; average p̄ = 0.054.
2. First term: z_1−α/2 × √[2p̄(1−p̄)] = 1.96 × 0.3203 = 0.6277.
3. Second term: z_1−β × √[p₀(1−p₀) + p₁(1−p₁)] = 0.842 × 0.3203 = 0.2695.
4. n = (0.6277 + 0.2695)² / (0.0041)² = 47,817.3, rounded up to 47,818 participants per arm for 80% power.

The smaller-effect rows in the table above repeat the same calculation with the effect multiplied by 0.75 and 0.5 (for ratios, applied to the logarithm of the ratio).

R code

alpha <- 0.05
z_a   <- qnorm(1 - alpha / 2)          # two-sided
p0 <- 0.0521739130434783                          # control proportion
p1 <- 0.0562770562770563                          # treatment proportion
n_per_arm <- function(power, frac = 1) {
  q1 <- p0 + (p1 - p0) * frac               # smaller effect = fraction of the observed difference
  pbar <- (p0 + q1) / 2
  z_b <- qnorm(power)
  ceiling(round((z_a * sqrt(2 * pbar * (1 - pbar)) + z_b * sqrt(p0 * (1 - p0) + q1 * (1 - q1)))^2 / (q1 - p0)^2, 6))
}
for (f in c(1, 0.75, 0.5))
  cat(sprintf("%3.0f%% of observed effect: n per arm = %s (80%% power), %s (90%% power)\n", 100 * f,
              format(n_per_arm(0.80, f), big.mark = ","), format(n_per_arm(0.90, f), big.mark = ",")))

# Check against R's built-in function (unrounded n per arm)
cat("power.prop.test:", round(power.prop.test(p1 = p0, p2 = p1, power = 0.80)$n, 1), "\n")

# Simulation: how often does the z-test reject at the 80%-power sample size?
set.seed(1347554)
n    <- n_per_arm(0.80)
reps <- 20000
x0 <- rbinom(reps, n, p0); x1 <- rbinom(reps, n, p1)
ph <- (x0 + x1) / (2 * n)
z  <- ((x1 - x0) / n) / sqrt(ph * (1 - ph) * 2 / n)
cat(sprintf("Simulated power at n = %s per arm: %.3f (%d replicates)\n", format(n, big.mark = ","), mean(abs(z) > z_a, na.rm = TRUE), reps))

Output from running the code

100% of observed effect: n per arm = 47,818 (80% power), 64,014 (90% power)
 75% of observed effect: n per arm = 84,251 (80% power), 112,788 (90% power)
 50% of observed effect: n per arm = 187,858 (80% power), 251,488 (90% power)
power.prop.test: 47817.3 
Simulated power at n = 47,818 per arm: 0.797 (20000 replicates)

The simulation draws many pairs of event counts at the planned sample size and counts how often the two-proportion z-test rejects the null. It should land close to the target power; at very small required sample sizes it can fall below it, because the normal approximation is rough there.

14. Multiplicity, Missing Data and Analysis Populations

The registry record lists a primary endpoint and several secondary outcomes, but it does not report a statistical analysis plan describing how multiplicity was addressed. It does not state whether secondary outcomes were prespecified as confirmatory, whether a testing hierarchy was used, or whether p-values were adjusted for multiple comparisons. The posted p-values are unadjusted. In general, when several outcomes are examined, the chance of at least one apparently unusual result can increase if each result is considered separately without accounting for the broader set of tests.

The record also lists zero reported analyses, and no analysis population is identified. It is not reported whether the primary comparison used all randomized participants, participants with available outcome data, or another population. The record does not state whether an intention-to-treat approach was planned or used, nor does it describe per-protocol or other analyses.

Missing-data information is not reported in the registry record. There are no posted counts for participants lost to follow-up, excluded from analysis, or missing endpoint assessments, and no method for handling missing values is described. This matters because incomplete follow-up can affect the estimated event risks if the participants with missing outcomes differ from those with recorded outcomes. Without participant flow and missing-data methods, the effect of incomplete ascertainment cannot be evaluated from the registry entries.

The record does not report interim analyses, stopping rules, or adjustments related to repeated looks at the data. It also does not describe covariate adjustment, stratification in the analysis, or a statistical model beyond the posted unadjusted comparisons. These details should not be inferred from the randomized design or from the reported p-values.

Finally, the composite endpoint appears in both the primary and secondary outcome listings with different counts and slightly different timeframe wording. The reason for the duplicate entry and differing counts is not reported in the registry record. This reporting issue leaves uncertainty about how the secondary entry relates to the primary endpoint, but it does not provide a basis for selecting one count over the other.

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

The registry results describe an observed comparison between two stent groups in a randomized, open-label trial of people with acute myocardial infarction. For the primary composite as designated in the record, the event counts are close, and the estimated risk difference is small relative to the uncertainty represented by its confidence interval. The posted comparison does not establish a clear difference in either direction, and it does not establish that the devices are equivalent.

A non-significant primary comparison is not proof that no meaningful difference exists. In general, a study can fail to distinguish a difference from zero when the effect is small, when the estimate is imprecise, or both. A formal equivalence or noninferiority conclusion requires a prespecified margin and an appropriate analysis; the registry record does not report such a margin or design.

The secondary outcomes add descriptive information but should be interpreted cautiously. The stent thrombosis comparison has a reported unadjusted p-value of 0.008, while the bleeding comparison is less decisive by its posted interval and p-value. Because multiple outcomes are listed and no multiplicity approach is reported, an isolated secondary result is not, on its own, a definitive overall conclusion. The two composite entries also differ in counts, and the record does not explain why.

The results do not establish the mechanism behind any observed event pattern, and they do not show which component of the primary composite contributed to the total. They also do not address all potential outcomes beyond those posted. Detailed follow-up, missing-data handling, event adjudication, and analysis-population information are not reported in the registry record, so the robustness of the estimates cannot be fully assessed.

Accordingly, the most defensible reading is limited to the recorded comparisons: the primary estimate is near zero with an interval spanning both directions; secondary findings vary by endpoint; and important analysis and reporting details are absent. The numbers do not constitute medical advice or a general recommendation about stent selection.

16. Why This Trial Matters Statistically

This trial is statistically notable because it compares two drug-eluting stent types in the acute myocardial infarction setting identified by the registry rationale. The record describes a randomized head-to-head comparison and lists a two-year device-oriented composite outcome, allowing a direct comparison of event counts between the two groups. This differs from a comparison against a bare metal stent or another drug-eluting stent class as described in the trial background.

The primary estimate illustrates why point estimates, confidence intervals, and p-values need to be read together. The observed event counts are close, but the interval still covers differences in both directions. A p-value alone cannot show the range of effects that remains compatible with the data, and a near-zero point estimate does not prove equivalence. The distinction is central when interpreting trials that do not report a formal equivalence or noninferiority framework.

The record also shows how secondary outcomes can complicate interpretation. The stent thrombosis result differs in pattern from the primary composite, while bleeding is less conclusive. Without a reported multiplicity plan, analysis hierarchy, and detailed endpoint methods, these comparisons should be treated as descriptive rather than as a set of equally strong confirmatory conclusions.

Finally, the differing counts for the identically titled primary and secondary composite entries highlight the importance of transparent outcome reporting. The registry does not explain the discrepancy, and statistical interpretation cannot resolve it. Readers need the endpoint definitions, participant flow, analysis population, and analysis plan to understand how posted results were produced and how they relate to one another.

17. 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 registry record gives limited detail on participant eligibility beyond the acute myocardial infarction setting and does not report the clinical or demographic characteristics of the enrolled groups. It also does not provide a participant-flow account, the number completing follow-up, or the number included in each endpoint analysis. The listed arm sizes therefore do not establish how complete the outcome data were at the two-year timeframe.

Outcome ascertainment and adjudication methods are not reported. The record does not describe whether events were independently reviewed, how myocardial infarctions not clearly attributable to a nontarget vessel were classified, or how target lesion revascularization was defined. Component-specific primary outcome counts are also absent, limiting interpretation of the composite result.

There is a reporting ambiguity: the primary and secondary listings include a device-oriented composite outcome with different counts. The registry record does not explain whether the entries reflect different definitions, analysis populations, data updates, or another reason. No explanation should be assumed.

The trial is listed as open-label, and the record does not say whether outcome assessors were masked. It does not report allocation concealment, the analysis population, missing-data methods, covariate adjustment, multiplicity handling, or the original sample-size justification. These omissions make it difficult to assess potential bias, analytic choices, and the degree to which the results match a prespecified plan.

The adverse-event fields list zero participants at risk or affected for serious and other adverse events in both groups, while deaths are not reported in those fields. The record does not explain these entries. They should not be interpreted as evidence that no adverse events occurred, particularly because a specific secondary outcome, any bleeding, is separately reported.

18. Related Tutorials

19. Related Statistical Calculators

20. Sources

• ClinicalTrials.gov: Efficacy of Everolimus-Eluting Versus Zotarolimus-Eluting Sten for Coronary Lesions in Acute Myocardial Infarction — NCT01347554.
• Registry record last updated 2014-09-29; status last verified 2014-09.
• Results first posted 2014-09-29.
• 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.

21. Record Summary

The registry record describes a completed, randomized, open-label, parallel-group phase 4 trial sponsored by Yonsei University. It enrolled 461 participants with acute myocardial infarction and compared the Xience V everolimus-eluting stent group with the Endeavor Resolute zotarolimus-eluting stent group. The recorded start was 2009-01, and the primary completion date was 2013-03.

The primary outcome was a two-year device-oriented composite of cardiac death, myocardial infarction not clearly attributable to a nontarget vessel, and target lesion revascularization. The primary entry lists 12 events among 230 participants in the Xience V group and 13 among 231 in the Endeavor Resolute group. Its risk-difference interval includes zero, and the unadjusted p-value is 0.846.

Secondary outcomes include a separately listed composite entry, stent thrombosis, and any bleeding. The record does not report analyses, the original sample-size rationale, missing-data handling, multiplicity methods, or an explanation for the differing composite counts.