Aversano T, Aversano LT, Passamani E, Knatterud GL, Terrin ML, Williams DO, Forman SA, for the Atlantic Cardiovascular Patient Outcomes Research Team (C-PORT) . Thrombolytic Therapy vs Primary Percutaneous Coronary Intervention for Myocardial Infarction in Patients Presenting to Hospitals Without On-site Cardiac SurgeryA Randomized Controlled Trial. JAMA. 2002;287(15):1943-1951. doi:10.1001/jama.287.15.1943
Author Affiliations: The Johns Hopkins Medical Institutions, Baltimore, Md (Dr Aversano and Ms Aversano); and Suburban Hospital, Bethesda, Md (Dr Passamani); Maryland Medical Research Institute, Baltimore (Drs Knatterud and Terrin and Ms Forman); and Rhode Island Hospital and Brown University, Providence (Dr Williams).
Context Trials comparing primary percutaneous coronary intervention (PCI) and
thrombolytic therapy for treatment of acute myocardial infarction (MI) suggest
primary PCI is the superior therapy, although they differ with respect to
the durability of benefit. Because PCI is often limited to hospitals that
have on-site cardiac surgery programs, most acute MI patients do not have
access to this therapy.
Objective To determine whether treatment of acute MI with primary PCI is superior
to thrombolytic therapy at hospitals without on-site cardiac surgery and,
if so, whether superiority is durable.
Design The Atlantic Cardiovascular Patient Outcomes Research Team (C-PORT)
trial, a prospective, randomized trial conducted from July 1996 through December
Setting Eleven community hospitals in Massachusetts and Maryland without on-site
cardiac surgery or extant PCI programs.
Patients Four hundred fifty-one thrombolytic-eligible patients with acute MI
of less than 12 hours' duration associated with ST-segment elevation on electrocardiogram.
Interventions After a formal primary PCI development program was completed at all
sites, patients were randomly assigned to receive primary PCI (n = 225) or
accelerated tissue plasminogen activator (bolus dose of 15 mg and an infusion
of 0.75 mg/kg for 30 minutes followed by 0.5 mg/kg for 60 minutes; n = 226).
After initiation of assigned treatment, all care was determined by treating
Main Outcome Measures Six-month composite incidence of death, recurrent MI, and stroke; median
hospital length of stay.
Results The incidence of the composite end point was reduced in the primary
PCI group at 6 weeks (10.7% vs 17.7%; P = .03) and
6 months (12.4% vs 19.9%; P = .03) after index MI.
Six-month rates for individual outcomes were 6.2% vs 7.1% for death (P = .72), 5.3% vs 10.6% for recurrent MI (P = .04), and 2.2% vs 4.0% for stroke (P =
.28) for primary PCI vs thrombolytic therapy, respectively. Median length
of stay was also reduced in the primary PCI group (4.5 vs 6.0 days; P = .02).
Conclusions Compared with thrombolytic therapy, treatment of patients with primary
PCI at hospitals without on-site cardiac surgery is associated with better
clinical outcomes for 6 months after index MI and a shorter hospital stay.
In several prospective randomized trials1- 3
and in a meta-analysis of such trials,4 primary
percutaneous coronary intervention (PCI) was superior to thrombolytic therapy
for treatment of patients with acute myocardial infarction (MI) associated
with ST-segment elevation on presenting electrocardiogram (ECG). Trial outcomes
differ primarily regarding whether the superiority of primary PCI was restricted
to short-term (30-day) outcomes3 or persisted
6 months after index MI.5,6
Most institutions participating in comparative trials have been hospitals
with on-site cardiac surgery and active elective PCI programs. Yet, approximately
two thirds of patients with acute MI present to hospitals without such capability.7 Although some of these hospitals have the equipment
and personnel capable of performing primary PCI, the requirement that cardiac
surgery be available in the same hospital usually prohibits its performance,
if not by state regulation, then by community standard.
The fact that access to primary PCI is restricted despite its superior
outcomes leads to a widely held position that attempts to justify two standards
of care. If it can be applied, primary PCI is the better therapy for acute
MI. If not, then thrombolytic therapy is the standard of care. Therefore,
whether a patient receives the better therapy depends on the hospital to which
the patient presents, which is itself almost always a matter of chance and
geography. From a health care policy point of view, access to the best therapy
for the greatest number of patients is an important goal.
This study, the Atlantic Cardiovascular Patient Outcomes Research Team
(C-PORT) trial, was undertaken to determine whether primary PCI produces outcomes
at 6 months that are superior to thrombolytic therapy when applied at hospitals
without on-site cardiac surgery or an extant PCI program. If primary PCI is
indeed the better therapy in this setting, then access to this procedure might
be extended to include the hospitals to which so many patients with acute
Based on a conservatively estimated event rate (composite of death,
recurrent MI, and stroke) of 14%1- 3
and α = .05, a sample size of 2550 was estimated to provide 90% power
to detect a 30% reduction in event rate. Five interim analyses were projected
before the final analysis. The first was to occur when 300 patients were recruited
and the second when 800 had been recruited. The Fleming-Harrington-O'Brien
method8 was used to maintain the overall type
I error rate for 2-sided comparison of treatment differences at α =
.05. The P value required to reject the null hypothesis
was .00101 for the first and .00111 for the second analysis. Because funding
could not be secured, the study was terminated after 451 patients were recruited.
Study patients were recruited between July 29, 1996, and June 17, 1999,
from 11 participating institutions in Maryland and Massachusetts. Prior to
study initiation, waivers to the prohibition of performing PCI at hospitals
without on-site cardiac surgery were secured from the appropriate regulatory
bodies in both states (the Maryland Health Care Commission and the Massachusetts
Department of Public Health Division of Health Care Quality). Waivers were
granted only for participation in the study and did not extend to PCI outside
of the study.
Each participating institution's institutional review board reviewed
and approved the study and consent. Written informed consent was obtained
from all participants using procedures in accordance with the ethical standards
of each participating institution's committee on human experimentation and
with the Helsinki Declaration of 1975, as revised in 1983.
Patients could be included if they were eligible to receive thrombolytic
therapy, were aged 18 years or older, could provide informed consent, had
chest discomfort or any other symptom compatible with myocardial ischemia
of at least 30 minutes' and less than 12 hours' duration, and had either at
least 1 mm of ST-segment elevation in at least 2 contiguous ECG leads or at
least 1 mm of ST-segment depression in leads V1 and V2
compatible with true posterior wall injury or presumed new left bundle-branch
block. Patients excluded were those unable to give informed consent, those
taking metformin who also had a creatinine level greater than 1.5 mg/dL (132.6
µmol/L) (in men) or 1.4 mg/dL (123.8 µmol/L) (in women), those
with true idiosyncratic reactions to aspirin or radiographic contrast media,
and those who were not eligible for thrombolytic therapy. Patients could present
to the emergency department or be inpatients and were not excluded because
of prior or recent MI, any comorbid condition (including those that might
limit survival to <6 months), or prior PCI or coronary artery bypass graft
(CABG) surgery. Patients with acute MI with ST-segment elevation on presenting
ECG who were ineligible for thrombolytic therapy could be entered into a registry
and undergo primary PCI at the community hospital (Figure 1).
The 11 community hospitals had coronary care units and diagnostic cardiac
catheterization laboratories but had neither an on-site cardiac surgical program
nor a preexisting PCI program. A formal program was created and used to develop
primary PCI capability at each institution prior to initiating patient recruitment.
The primary PCI development program was a detailed process that took approximately
3 months to complete and was individually adapted for each institution. This
program consisted of setting standards, training staff, developing local logistics,
and instituting a quality and error management program. Additional details
regarding this program are available at http://www.cport.org.
Standards were required for care, facilities, equipment, and staff,
including interventional operators and catheterization laboratory and postprocedure
(coronary care unit) staff. Care standards adopted were the American College
of Cardiology/American Heart Association MI treatment guidelines.9 Facilities and equipment standards were set locally
by the interventional operators. In addition, an instrument for measuring
activated clotting time and an intra-aortic balloon pump were required. Interventional
operators had to perform a minimum of 50 interventions per year.10
There were no nationally recognized competency standards for nurses and technicians
caring for primary PCI patients, so a formal training program was implemented.
Training consisted of three parts: on-site observational training, a didactic
series, and hands-on training for staff serving as second operator.
Logistics development refers to creation of an infrastructure that allows
for the appropriate, safe, rapid, reliable, and effective application of therapy
for acute MI. For thrombolytic therapy, the 2 goals were immediate receipt
of aspirin and application of thrombolytic therapy within 30 minutes of hospital
arrival. For primary PCI, the 3 goals were immediate receipt of aspirin, no
more than 60 minutes' elapsed time from hospital arrival to entry into the
catheterization laboratory, and no more than 90 minutes' elapsed time from
hospital arrival to first balloon inflation. Detailed logistics were developed
by study staff and local staff from the various care areas, including the
emergency department, cardiac catheterization laboratory, and coronary care
unit, and were individualized for each institution.
Quality and error management required collection of data for each patient.
Both process indicators (eg, time to treatment) and clinical outcomes indicators
(eg, death, stroke) of quality were monitored.
This trial was meant to be a "real-world" trial and, therefore, was
developed with a minimum amount of protocol-required care. The Maryland Medical
Research Institute (MMRI) served as the trial data coordinating center and
the Johns Hopkins Medical Institutions as the clinical coordinating center.
Patients were identified as potential trial participants in the emergency
department or in the hospital. Treatment assignments were made with an automated
telephone response system at MMRI. This system was accessible 24 hours a day
to individuals with certification to enroll patients in the study. The individual
identifying and randomizing the patient (usually an emergency department physician)
was often not the treating physician (most often a cardiologist). Separate
randomization treatment assignment schedules were computer generated for each
clinical site, balancing assignments within site in randomly varying blocks
of size 2, 4, 6, and 8, so that assignments to each of the 2 treatment groups
had equal expectations.
Patients randomized to receive thrombolytic therapy were required to
receive immediate aspirin, accelerated tissue plasminogen activator (bolus
dose of 15 mg and an infusion of 0.75 mg/kg for 30 minutes followed by 0.5
mg/kg for 60 minutes), and 48 hours of postthrombolytic heparin. Patients
randomized to receive primary PCI were required to receive immediate aspirin.
No protocol PCI was to be performed if the patient had both clinical resolution
of ischemia (resolution of ST-segment elevation and chest discomfort) and
Thrombolysis in Myocardial Infarction (TIMI) grade 3 flow on initial angiography.
Additional guidelines for interventional treatment included encouragement
to use stents for any residual stenosis of greater than 20% or any other suboptimal
result, such as angiographically demonstrable intimal dissection, and encouragement
to use glycoprotein IIb/IIIa receptor antagonists. While application of nationally
recognized acute MI care guidelines9 were recommended
in the trial's manual of operations, treatment of patients was determined
by the local treating physician.
Follow-up at 6 weeks and 6 months was performed primarily through telephone
contact. All medical records related to an identified event were reviewed.
The primary outcome measure was the composite incidence 6 months after
index MI of the first occurrence of death, recurrent MI, and stroke. Stroke
was defined as any new, permanent neurological deficit. Recurrent MI was defined
as in the Assessment of the Safety and Efficacy of a New Thrombolytic (ASSENT)
2 trial.11 Within the first 18 hours after
index MI, recurrent MI required recurrent symptoms of myocardial ischemia
associated with recurrent ST-segment elevation in at least 2 contiguous leads
lasting at least 30 minutes. After 18 hours, recurrent MI was defined as appearance
of new Q waves, new left bundle-branch block, or enzyme evidence of MI. This
included either an abnormal creatine kinase (CK) MB fraction that was also
at least 50% greater than the immediately prior value. If only total CK measurement
was available, it was required to be elevated to more than 2 times the upper
limit of normal and at least 25% greater than the immediately previous value;
if total CK level was not 2 times the upper limit of normal, then it had to
be at least 50% greater than the upper limit of normal and at least 2 times
the immediately previous value. Periprocedural recurrent MIs required, following
PCI, a CK-MB fraction or total CK level 2 times the upper limit of normal
and at least 50% greater than the immediately previous value and, following
CABG surgery, a CK-MB fraction or total CK level at least 5 times the upper
limit of normal and at least 50% greater than the immediately previous value.
Alternatively or additionally, periprocedural recurrent MI was defined as
appearance of new Q waves in 2 or more contiguous leads.
Death was confirmed using the Social Security Death Index and/or a death
certificate. Recurrent MI events were reviewed by at least 2 cardiologists
not associated with the trial and blinded to treatment allocation. Stroke
events were reviewed by a neurologist not associated with the trial and blinded
to treatment allocation.
Secondary end points measured included incidence of blood transfusion,
nonprotocol catheterization and PCI, CABG surgery, and length of stay. All
protocol angiograms and interventions were reviewed and interpreted by the
study chairman (T.A.). Quantification of coronary artery stenoses and TIMI
flow grade were estimated visually. Successful PCI was defined as a postprocedure
result of no more than 50% residual stenosis and TIMI grade 3 (or normal)
Results are presented as either mean (SD) or median (interquartile range).
Comparisons of incidence of each individual outcome and the primary composite
outcome by intention-to-treat analysis were performed using the χ2 test for categorical variables and the t
test for continuous variables. The intention-to-treat analysis was performed
for all randomized patients as randomized. Survival analyses were evaluated
using the log-rank test. Significant differences required a 2-tailed P≤.05. Analyses were carried out using SAS (SAS Institute
Inc, Cary, NC) and Statistica (StatSoft Inc, Tulsa, Okla).
The data and safety monitoring board for the trial approved the protocol
and amendments, provided interim safety monitoring, and concurred with the
decision to close the trial. The randomized trial was closed after the second
interim analysis because, after multiple attempts, funding could not be secured.
The first of 11 participating centers began patient recruitment on July
29, 1996, and the last began recruitment on October 14, 1998. The last of
451 patients was randomized on June 17, 1999. The highest-enrolling center
enrolled 138 patients and the lowest-enrolling center enrolled 7 patients.
Baseline patient characteristics are shown in Table 1. There were no significant differences between treatment
groups with regard to baseline characteristics, prevalence of cardiac risk
factors, common comorbid conditions, or presenting signs.
Assigned treatment was considered to have been received if thrombolytic
therapy was initiated in patients assigned to thrombolytic therapy and if
catheterization was performed with or without PCI in patients assigned to
the primary PCI group. Twenty-two (9.7%) of the 226 patients assigned to thrombolytic
therapy did not receive assigned thrombolytic therapy and 13 (5.8%) of 225
patients assigned to primary PCI did not undergo catheterization (Figure 1). Seven patients assigned to primary
PCI received thrombolytic therapy and 2 assigned to thrombolytic therapy received
primary PCI at the community hospital.
In 43 patients assigned to primary PCI, catheterization was performed
but PCI was not attempted: in 31 per protocol because the infarc-related artery
was patent and ischemic signs and symptoms resolved, in 7 because of high-risk
anatomy requiring coronary artery surgery, and in 5 for other reasons. Percutaneous
coronary intervention was successful in 163 (96%) of 169 patients in whom
it was attempted. Among those in whom PCI was attempted, 106 (63%) had stents
placed and 128 (76%) were given a glycoprotein IIb/IIIa receptor antagonist
(all but 2 patients received abciximab).
Hospital arrival times are shown in Table 2. The distribution of arrival times was the same in both
groups, with more than half of the patients arriving during the day (8 AM–4
PM). In the thrombolytic therapy group, patients arrived at the hospital a
median of 90 minutes (IQR, 60-200 minutes) after symptoms began; patients
in the primary PCI group arrived 90.5 minutes (IQR, 59-170 minutes) after
symptom onset. In the thrombolytic therapy group, the median door-to-therapy
time was 46 minutes (IQR, 30-65 minutes). In the primary PCI group, the median
door–to–catheterization laboratory time was 55 minutes (IQR, 40-75
minutes) and the median door-to-balloon time was 101.5 minutes (IQR, 82-121
As shown in Table 3, by
intention-to-treat analysis, each major adverse outcome—death, recurrent
MI, stroke, and the composite end point—were lower at discharge, 6 weeks,
and 6 months in the primary PCI group. For the composite end point, the odds
ratio was 0.52 (95% confidence interval, 0.30-0.89) at 6 weeks and 0.57 (95%
confidence interval, 0.34-0.95) at 6 months in favor of primary PCI. The lower
adverse event rates after index MI were due mainly to lower rates of recurrent
MI and stroke. As shown in Figure 2,
the benefit of primary PCI was seen mainly in the first 10 days after index
When patients from the center with the greatest number of enrolled participants
were eliminated from analysis, the composite event rate among patients from
the other centers still favored primary PCI. In the highest-enrolling center,
the composite event rate at 6 months was 23.2% in the thrombolytic therapy
group and 13.0% in the primary PCI group. Excluding patients in the highest-enrolling
center, the 6-month composite event rate from the other centers was 18.5%
in the thrombolytic therapy group and 11.5% in the primary PCI group. The
relative reduction in the 6-month composite event rate was similar in the
highest-enrolling center and in patients from the other centers (44% and 38%,
When these data were analyzed by actual treatment received (comparing
those in the trial who actually received primary PCI at the community hospital
with those who actually received thrombolytic therapy), outcomes favor primary
PCI even more, as shown in Table 4.
At 6 months, there was more than a 50% relative reduction (10.5% absolute
reduction) in the composite event rate in the primary PCI group.
Table 5 summarizes the incidence
of other common post–index MI events. Red blood cell transfusions were
given in twice as many patients treated with primary PCI compared with thrombolytic
therapy. No patient in the primary PCI group was sent for emergency CABG surgery
for a catheterization-related or PCI-related complication, including abrupt
closure, dissection, or coronary perforation due to a complication at the
index hospital. Two thrombolytic therapy patients required emergency CABG
surgery following elective PCI at a tertiary center, one because of dissection
and threatened closure and the other because of coronary perforation. Both
did well without significant sequelae. In addition, 1 patient in the primary
PCI group required vascular surgery to retrieve a dislodged coronary stent
from a peripheral (noncoronary) artery.
The median length of stay for the index MI (including both community
hospital days and tertiary hospital days, if the patient was transferred for
additional care) was 4.5 days (IQR, 3-6 days) in the primary PCI group and
6 days (IQR, 4-8 days) in the thrombolytic therapy group (P = .02). Sixty-nine percent of the thrombolytic therapy group was
transferred to a tertiary hospital for additional care, whereas 31% of the
primary PCI treatment group was transferred (P =
.002). No patient was transferred to a tertiary facility because of a complication
of primary PCI.
Primary PCI, rather than being simply a procedure performed by an expert
interventionist, is instead a strategy of care involving a team of health
care personnel in multiple care areas, including the emergency department,
coronary care unit, cardiac catheterization laboratory, and, ideally, the
prehospital transport system. Its development must include careful, detailed
attention to standards, training, logistics, and quality and error management
in each of these areas. Seamless integration of care across these areas is
necessary to ensure prompt, appropriate, and efficacious application of primary
PCI. We believe that the development program used in this study significantly
influenced the quality of care and contributed importantly to the favorable
outcomes in the primary PCI group, and may have improved medical care as well.
Comparison of outcomes among the Atlantic C-PORT trial, the larger randomized
trials, and a meta-analysis of them is shown in Table 6. Primary PCI was superior to thrombolytic therapy in our
trial, in the 3 largest previously reported randomized trials,1- 3
and in the latest meta-analysis of all randomized trials.4
Although the incidence of outcomes differs among these studies, the direction
of benefit was the same, all favoring primary PCI. Outcome differences may
be due to a number of factors, including differences in characteristics of
the population studied, differences in definitions of outcome, and differences
due to care provided.
Since the Atlantic C-PORT trial was meant to be a real-world comparison
of alternative therapies, examining outcomes in the context of recent acute
MI registry reports is of interest. Of particular interest are the main outcome
and process indicators of quality of care, mortality, and time to treatment,
In a report based on the National Registry of Myocardial Infarction
(NRMI) database, Magid et al13 reported that
mortality at discharge of patients treated with primary PCI was 6.2% at hospitals
performing a low volume of PCI (<16 cases per year), 4.5 % at intermediate-volume
hospitals (17-48 cases per year), and 3.4 % at high-volume hospitals (>49
cases per year). Corresponding mortality among patients treated with thrombolytic
therapy averaged approximately 6% at all institutions. Primary PCI was superior
to thrombolytic therapy only at hospitals with intermediate and high procedure
volumes. Although overall mortality in our trial was 5.3% in patients randomized
to primary PCI, registries report outcomes only for patients actually undergoing
the procedure. For the patients in our trial who actually underwent attempted
primary PCI, mortality was 4.1%, similar to the outcomes reported at the high-
and intermediate-volume hospitals among thrombolytic-eligible patients.13 Because our patient population was small, no clinically
meaningful or statistically significant statements can be made regarding any
potential volume-outcome relationship in hospitals performing primary PCI
without on-site cardiac surgery and in the absence of an elective PCI program.
Comparison of treatment times between our trial and other randomized
trials is made difficult by the fact that in other trials, treatment time
is usually measured from the time of randomization, not hospital admission
(or "door") time. Because time to treatment measured from hospital admission
is an important process indicator of quality of care and a predictor of outcome
for both thrombolytic therapy and primary PCI,14
we reported this parameter. Our treatment times are best compared with recently
reported registry data. Median door–to–thrombolytic therapy time
was approximately 40 minutes nationwide in the NRMI report during the years
patients were recruited into our study,15 while
the median door–to–thrombolytic therapy time in our study was
46 minutes. The mean door-to-balloon time was 105.2 minutes in our trial (median,
101.5 minutes), which represents a treatment time at least as good as the
average of 120 minutes reported at the lowest-mortality (highest-volume) institutions
in the NRMI registry.13
The original sample size for this trial was planned to be 2550 (see
Methods section). Because funding could not be secured for its completion,
the study was terminated after 451 patients were randomized, making it significantly
underpowered. Nevertheless, this trial remains the second-largest prospective,
randomized trial comparing primary PCI with thrombolytic therapy for treatment
of acute MI. It is the only study performed exclusively in hospitals without
on-site cardiac surgery and performed when stents and glycoprotein IIb/IIIa
receptor antagonists were widely available. Thus, despite this limitation,
results from the trial are of significant interest.
Another potential limitation is selection bias, which could be introduced
by the concurrently running primary PCI registry for thrombolytic-ineligible
patients. A physician or institution favoring primary PCI could deem a patient
ineligible for thrombolytic therapy and perform primary PCI, preventing that
patient from being randomized. This potential source of bias is an issue for
any trial, including those previously reported. Its influence was minimized
in our trial because thrombolytic-ineligible patients in our trial were entered
into a separate study, then reviewed, monitored, and followed up in the same
way as those randomized. On review, all patients deemed ineligible for thrombolytics
were, in fact, ineligible by conventional criteria.
Another possible source of bias in our trial is differential recruitment
rates based on time of day. Nationally, the distribution of emergency department
arrival times for primary PCI patients differs from that of patients treated
with thrombolytic therapy, also shown in Table 2. This suggests that there is a tendency to perform primary
PCI during the day (8 AM to 4 PM), while thrombolytic therapy is administered
more evenly throughout the 24-hour period. Because of randomization, primary
PCI and thrombolytic therapy had nearly identical emergency department arrival
time distributions in our trial and both were more like the distribution for
primary PCI in high-volume hospitals recorded in the NRMI registry13 (Table 2).
Thus, while it is true that 62% of our patients were enrolled during the day,
this is not very different from what occurs in the real-world practice of
primary PCI, as reflected in the NRMI data.
The current standard of practice is to complete PCI in patients with
acute MI, even if the infarction-related artery is patent at catheterization.
In our study, PCI was not performed when the infarction-related artery was
patent and symptoms and electrocardiographic signs of myocardial ischemia
were resolved at the time of catheterization, consistent with the principle
of "first, do no harm." The data from our study do not directly bear on whether
primary PCI should be undertaken in this particular setting.
Our trial was too small to define any potential relationship between
institutional volume and outcome. Thus, whether there is an institutional
volume of procedures below which primary PCI outcomes deteriorate cannot be
determined from these data. Currently, the literature supports 36 procedures
per year as the lowest number that should be performed by an institution offering
primary PCI.16 However, this number is gleaned
from institutions with relatively high-volume elective PCI programs, and its
applicability to community hospitals performing primary PCI exclusively is
Finally, it is important to note that our results apply only to primary
PCI for patients with acute MI with ST-segment elevation or left bundle-branch
block on presenting ECG. They do not apply to rescue PCI after failed thrombolysis,
to other unstable coronary syndromes such as unstable angina or MI associated
with a nondiagnostic ECG, or to elective PCI.
Our study adds to the evidence suggesting that there is no need for
on-site cardiac surgery to back up primary PCI. Abrupt closure or dissection
requiring emergency coronary surgery did not occur in our trial and is extremely
rare in primary PCI because the infarction-related artery is usually totally
occluded from the outset. Although coronary perforation remains a possible
major iatrogenic adverse event, it did not occur in patients undergoing primary
PCI at the community hospitals, and its occurrence, particularly when only
balloons and stents are used, is rare (approximately 0.1%).17
The availability of covered stents18 may make
nonsurgical treatment of many perforations possible.
Our study suggests that access to primary PCI can be increased by extending
primary PCI capability to hospitals without on-site cardiac surgery that complete
a formal development program. How many additional primary PCI programs are
needed to provide adequate access is an important question that will be determined
locally. The number might be minimized by development of a system of cardiac
care on the state or local level analogous to the trauma system of care. In
such a system, all hospitals would participate, but there would be a logical
distribution of several levels of service among institutions tied to an emergency
transport system that triages patients to the appropriate level of care. Integration
of destination hospitals with the emergency transport system could reduce
treatment time by providing adequate information from the field to assemble
the primary PCI team before the patient arrives at the hospital and reduce
the possibility that the treatment a patient receives for acute MI is a matter
of chance and geography.
An alternative to increasing access by increasing the number of PCI
programs is transfer of patients from hospitals that do not have this capability
to those that do. While this alternative is in current use, it is limited
in its ability to improve access. Transfer time may be quite long in both
rural and urban settings, with distance and weather being a major issue in
the former circumstance, and limited interhospital transport capacity an important
problem in the latter. Consequently, interhospital transfer is an unreliable
method of minimizing the time between symptom onset and application of therapy
in acute MI.
This trial demonstrates that, after an extensive development program,
primary PCI can be performed safely, promptly, and effectively in the community
hospital without an elective PCI or cardiac surgery program. Furthermore,
compared with thrombolytic therapy, primary PCI treatment of patients with
acute MI presenting to such hospitals is associated with a significant and
sustained reduction in incidence of the composite adverse outcome of death,
recurrent MI, and stroke.
A number of issues require further research. The primary PCI development
program continues to evolve, focusing now on elements required to sustain
good outcomes in the absence of a monitored trial. Quality and error management
are important elements of this effort, but mechanisms to provide accountability
and to compare outcomes with community standards are likely to be important
as well. The relationship between institutional volume and outcome remains
to be established in hospitals without on-site cardiac surgery. The ongoing
Atlantic C-PORT primary PCI registry conducted in community hospitals without
elective PCI programs may help to establish this relationship. Finally, research
into how access to primary PCI is best expanded, taking into consideration
the medical, quality-of-life, and economic consequences of expansion, is important.
Such research could establish a rational basis for adding needed capacity
without excessive proliferation of programs that can not only dilute institutional
volume but also strain limited human resources.
We conclude that primary PCI is superior to accelerated thrombolytic
therapy for treatment of acute MI in the community hospital setting and that
superiority is sustained for at least 6 months after index MI. A formal primary
PCI development program is important in ensuring good outcomes with this procedure.