| The Current Status of Primary
Percutaneous Coronary Intervention
Numerous publications and randomized clinical trials have convincingly
demonstrated the superiority of primary angioplasty
(PPCI) over thrombolytic therapy for ST-elevation myocardial
infarction (STEMI), provided that it is instituted in a timely fashion.
1–10 In a quantitative review of 23 randomized trials, PPCI was
better than thrombolytic therapy at reducing overall short-term
death, 7% vs. 9%, respectively, and also demonstrated improved
long-term outcomes.11 Several trials have shown that short door-toballoon
(DTB) times improve early and late outcomes in PPCI.12–19
DTB times of 90 minutes or less have been shown to be associated
with smaller infarct sizes, fewer major adverse cardiovascular
events (MACE) and better long-term survival.17–19 The National
Registry of Myocardial Infarction (NRMI) database demonstrated a
strong relationship between DTB time and in-hospital mortality
among 29,222 patients with STEMI.When treatment was started
within 90 minutes after arrival, in-hospital mortality was 3.0%, but it
increased to 4.2%, 5.7% and 7.4% with delays of 91–120 minutes,
121–150 minutes and > 150 minutes, respectively. After adjustment
for differences, each 15-minute reduction in DTB time was associated
with 6.3 fewer deaths per 1000 patients treated15 (Figure 1).
Similarly, 30-day and 1-year mortality are also proportional to the
DTB time.15,16 With such clear and demonstrable improvements in
morbidity and mortality benefits, it was a natural transition for
guidelines and practices to rapidly shift. Based on this data, the
American College of Cardiology (ACC), in conjunction with the |
American Heart Association (AHA), as well as the European
Society of Cardiology, recommend that primary angioplasty should
be performed within 90 minutes of presentation (or the time from
initial medical contact).20,21 The ACC/AHA guidelines state:
If immediately available, primary PCI should be performed in
patients with STEMI (including true posterior myocardial infarction
[MI]) or MI with new or presumably new left bundle branch block
(LBBB) who can undergo PCI of the infarct artery within 12 hours of
symptom onset, if performed in a timely fashion (balloon inflation within
90 minutes of presentation) by persons skilled in the procedure…20
Data from NRMI, however, demonstrate that in 1999, only
35% of patients undergoing PPCI were treated within the recommended
90-minute DTB time, and improvement from 1999
to 2002 was slow, with only 26% of hospitals improving DTB
time by more than 3 minutes/year.22
As a result of this remarkable evolution in recognizing the
importance of STEMI, various changes have occurred and
are ongoing in the management of STEMI patients.ACC/AHA
guidelines have established new directives for the early management
of STEMI patients and have clearly delineated Class I indications
including a goal DTB time of < 90 minutes20 (Table 1).
Based on these recommendations and established standards of
care, other organizations on various levels, including international,
national and regional, have followed suit.
1. The United States has taken an early global lead in its
nationwide quality initiative to provide aggressive management
for STEMI patients.
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