Transcript Slides - Clinical Trial Results

Outcomes for Patients with ST-Elevation
Myocardial Infarction in Hospitals With and
Without Onsite Coronary Artery Bypass Graft
Surgery: The New York State Experience
Hannan EL, Zhong Y, Racz M, Jacobs AK, Walford G, Cozzens K,
Holmes DR, Jones RH, Hibberd M, Doran D, Whalen D, King
SB III. Circulation: Cardiovascular Interventions, published
ahead of print 11/10/09.
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Background
• The benefit of primary percutaneous coronary
interventions (P-PCI) for patients with ST-elevation
myocardial infarction (STEMI) has been welldocumented.
• However, controversy still exists as to whether PCI
should be expanded to hospitals without coronary
artery bypass graft (CABG) surgery.
• Elective PCI at hospitals without onsite CABG
surgery is currently not recommended in the most
recent ACC/AHA guidelines
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Purpose of Study
• To compare long- and short-term outcomes
for STEMI patients in NY hospitals without
CABG surgery backup (P-PCI centers) to those
in hospitals with backup (called Full Service
(FS) centers).
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Methods
• Patients and Outcomes: STEMI Patients Undergoing
PCI
– Observational study of 1735 patients who were discharged
after PCI for STEMI between 1/1/03 and 12/31/06 in P-PCI
centers were propensity-matched to 8817 patients in full
service (FS) centers to obtain 1729 pairs of patients with
very similar propensity scores.
– These patients were followed through the end of 2006 and
outcomes of patients treated in P-PCI centers were
compared with outcomes of patients in FS centers.
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Methods, Cont’d
• Patients and Outcomes: STEMI Patients
Undergoing PCI
– Outcomes that were examined included inhospital mortality and need for CABG surgery,
and three-year mortality, repeat target vessel PCI
and subsequent revascularization.
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Methods, Cont’d
•
Patients and Outcomes: STEMI Patients Not
Undergoing PCI
– Patients: Observational study comparing
all STEMI patients presenting at P-PCI
centers not undergoing PCI (34.3% of all
pts.) and all STEMI patients presenting at
FS centers not undergoing PCI (30.3% of all
pts.)
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Methods, Cont’d
• Patients and Outcomes: STEMI Patients Not
Undergoing PCI
– Outcome: The outcome used was riskadjusted in-hospital mortality using the
variables used in the CMS AMI reports for
the risk-adjustment process (no out-ofhospital mortality was available for these
pts).
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Results
• Variables used in the propensity matching included:
– Age, sex, race
– Ejection fraction, congestive heart failure, previous AMI, shock,
hemodynamic instability
– Several comorbidities (renal failure, COPD, diabetes,
carotid/cerebrovascular disease, peripheral vascular disease,
ventricular arrhythmia
– Previous revascularization
– Anatomic group (no. of vessels diseased and presence absence of
proximal LAD disease)
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Results
• Prior to propensity matching, patients in FS centers were
sicker (lower ejection fractions, higher
comorbidity rates, more likely to be hemodynamically
unstable or in shock, more likely to have congestive heart
failure).
• After propensity matching, there were no differences based
on an examination of % standardized differences in risk factor
prevalences.
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Results: Short-Term Outcomes for Pts with PCI
•
For patients undergoing PCI, there were no
differences for in-hospital/30-day mortality (2.3%
for P-PCI centers vs. 1.9% for FS centers (P=0.40)),
emergency CABG surgery immediately following
PCI (0.06% vs. 0.35%, P=0.06).
•
However, P-PCI centers had a lower same/next
day CABG rate (0.23% vs. 0.69%, P=0.046).
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Results: Short-Term Outcomes for Pts without
PCI
• A higher percentage of STEMI patients arriving at P-PCI
centers did not undergo PCI (34.3% vs. 30.3%)
• These patients had significantly higher mortality rates
(28.5% vs. 22.3%, adjusted OR =1.38, 95% CI (1.10, 1.77)).
• After removing the patients who died within 2 hours of
arriving at the hospital, P-PCI center patients still had higher
mortality rates (adjusted OR= 1.39, 95% CI (1.10, 1.77)).
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Results: Longer-Term Outcomes for Pts with PCI
• For patients undergoing PCI, there were no
differences in three-year mortality (6.8% vs.
6.9%, P=0.63) or subsequent
revascularization (23.4% vs. 20.7%, P=0.11).
• However, P-PCI centers had higher repeat
target vessel PCI rates (12.4% vs. 9.2%,
P=0.0005).
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Mortality Rates and P-values for Matched STEMI Patients Undergoing
Primary PCI in P-PCI Centers and Full Service Centers: New York, Jan. 2003 Dec. 2006
Short-Term Outcomes
Rate in Primary
PCI Centers
Rate in Full
Service Centers
P-value
In-Hospital/30 day Mortality
2.31%
1.91%
0.40
Emergency CABG Surgery
0.06%
0.35%
0.06
Same day/next day CABG
0.23%
0.69%
0.046
Longer-Term Outcomes
Rate in Primary
PCI Centers
Rate in Full
Service Centers
P-value
3-Year Mortality
3-Year Repeat Target
Vessel PCI
3-Year Subsequent
Revascularization
7.1%
5.9%
0.07
12.1%
9.0%
0.003
23.8%
21.5%
0.52
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Caveats
• Operators in New York P-PCI centers were required to perform at least
200 PCIs in the past 3 years, 75 PCIs per year and 11 P-PCIs per year on a
regular basis. Also, P-PCI centers were required to ensure 24/7/365
coverage for P-PCI, maintain a volume of 36 P-PCIs per year, and
maintain an active affiliation with a high-volume FS center. Hence, P-PCI
center results in less restrictive settings could be worse.
• The study is observational and therefore subject to possible selection
bias. However, propensity matching was used to adjust for baseline
differences. Also, it would be impractical to conduct an RCT for this type
of study given that many patients are transported by ambulance.
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Caveats, Cont’d
• It is possible that P-PCI centers were at a disadvantage
because they were in a startup period during which teams
were becoming accustomed to one another and to a new
procedure being performed in the hospital.
• To test for this bias, we repeated the analyses after
excluding the first year of operation, and found that the
results were essentially the same (the significant differences
remained).
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Conclusions
• Summary: No differences between P-PCI centers and FS
centers were found in in-hospital/30 day mortality, the need
for emergency surgery, three-year mortality or subsequent
revascularization
• Summary: However, P-PCI centers had higher repeat TV PCI
rates and higher mortality rates for patients not undergoing
PCI.
• Conclusion: P-PCI centers should be monitored closely,
including the monitoring of STEMI patients who do not
undergo PCI.
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