Temporal changes in patient characteristics and outcomes in ST-segment elevation myocardial infarction 2003-2018.

BACKGROUND: We sought to describe changes in demographic variables, process of care measures, and outcomes of patients treated in a regional ST-segment elevation myocardial infarction (STEMI) program over the last 15 years. METHODS: We describe demographic variables, process of care measures, and outcomes of patients treated in the program in various 5-year time periods: 2003-2007 (n = 1,821), 2008-2012 (n = 1,968), and 2013-2018 (n = 2,223). The primary outcome measures were in-hospital and 30-day mortality. RESULTS: Among 6,012 STEMI patients treated from 2003 to 2018 we observed a significant increase in mean age at presentation (62 ± 14 to 64 ± 13 years) and diabetes (14-22%, p < .01). The proportion of patients with cardiogenic shock (CS) and cardiac arrest (CA) pre-PCI increased significantly from 9.5% to 11.1% and 8.5% to 12.7% (p < .05), respectively. The median door-to-balloon (D2B) times decreased from 98 to 93 min and total ischemic time decreased from 202 to 185 min (all p < .05). Despite increased patient complexity, the proportion of nontransfer and transfer patients achieving D2B times consistent with guideline recommendations remained unchanged (for nontransfer patients 79-82%, p = .45 and for transfer patients 65-64%, p = .34). Among all STEMI patients, in-hospital mortality increased during the study period from 4.9 to 6.9% (p = .007) but remained stable (<2%) when CA and CS patients were excluded. CONCLUSIONS: Over the last 15 years, short-term STEMI mortality has increased despite improvements in care delivery metrics. Patients with CA and/or CS now represent 10% of STEMI patients and are responsible for 80% of deaths. Therefore, efforts to improve STEMI mortality, and metrics for assessing STEMI programs, should focus on these patients.

NHLBI-Sponsored Randomized Trial of Postconditioning During Primary Percutaneous Coronary Intervention for ST-Elevation Myocardial Infarction.

RATIONALE: Postconditioning at the time of primary percutaneous coronary intervention (PCI) for ST-segment-elevation myocardial infarction may reduce infarct size and improve myocardial salvage. However, clinical trials have shown inconsistent benefit. OBJECTIVE: We performed the first National Heart, Lung, and Blood Institute-sponsored trial of postconditioning in the United States using strict enrollment criteria to optimize the early benefits of postconditioning and assess its long-term effects on left ventricular (LV) function. METHODS AND RESULTS: We randomized 122 ST-segment-elevation myocardial infarction patients to postconditioning (4, 30 seconds PTCA [percutaneous transluminal coronary angioplasty] inflations/deflations)+PCI (n=65) versus routine PCI (n=57). All subjects had an occluded major epicardial artery (thrombolysis in myocardial infarction=0) with ischemic times between 1 and 6 hours with no evidence of preinfarction angina or collateral blood flow. Cardiac magnetic resonance imaging measured at 2 days post-PCI showed no difference between the postconditioning group and control in regards to infarct size (22.5±14.5 versus 24.0±18.5 g), myocardial salvage index (30.3±15.6% versus 31.5±23.6%), or mean LV ejection fraction. Magnetic resonance imaging at 12 months showed a significant recovery of LV ejection fraction in both groups (61.0±11.4% and 61.4±9.1%; P<0.01). Subjects randomized to postconditioning experienced more favorable remodeling over 1 year (LV end-diastolic volume =157±34 to 150±38 mL) compared with the control group (157±40 to 165±45 mL; P<0.03) and reduced microvascular obstruction ( P=0.05) on baseline magnetic resonance imaging and significantly less adverse LV remodeling compared with control subjects with microvascular obstruction ( P<0.05). No significant adverse events were associated with the postconditioning protocol and all patients but one (hemorrhagic stroke) survived through 1 year of follow-up. CONCLUSIONS: We found no early benefit of postconditioning on infarct size, myocardial salvage index, and LV function compared with routine PCI. However, postconditioning was associated with improved LV remodeling at 1 year of follow-up, especially in subjects with microvascular obstruction. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov . Unique identifier: NCT01324453.

ST-elevation myocardial infarction diagnosed after hospital admission.

BACKGROUND: Treatment times for ST-elevation myocardial infarction (STEMI) patients presenting to percutaneous coronary intervention hospitals have improved dramatically over the past 10 years, particularly for patients using emergency medical services. Limited data exist regarding treatment times and outcomes for patients who develop STEMI after hospital admission. METHODS AND RESULTS: With the use of a comprehensive prospective regional STEMI program database, we evaluated the characteristics and outcomes for patients who develop STEMI after hospital admission. Of the 3795 consecutive STEMI patients treated by the use of the Minneapolis Heart Institute regional STEMI program from March 2003 to January 2013, 990 (26.1%) presented initially to the percutaneous coronary intervention facility, including 640 arriving via emergency medical services, 267 self/family driven, and 83 already admitted to the hospital. Patients with in-hospital presentation were older with higher body mass indexes, were more likely to have hypertension, and to present with pre-percutaneous coronary intervention cardiac arrest and cardiogenic shock. Door-to-balloon times (diagnostic ECG-to-balloon for in-hospital patients) were longer than for patients using emergency medical services (76 versus 51 minutes; P<0.001), but similar to self/family-driven patients (76 versus 66 minutes; P=0.13). In-hospital patients had longer lengths of stay (5 versus 3 versus 3 days; P<0.001) and higher 1-year mortality (16.9% versus 10.3% versus 7.1%; P=0.032). These patients frequently had high-risk and complex reasons for admission, including 30.1% with acute coronary syndrome, 22.9% postsurgery, 13.3% respiratory failure, and 8.4% ventricular fibrillation. CONCLUSIONS: Patients who develop STEMI while in-hospital represent a unique, high-risk subset of patients. They have increased treatment time and lengths of stay and higher mortality rates than the patients presenting via emergency medical services or who are self/family driven.

A regional system to provide timely access to percutaneous coronary intervention for ST-elevation myocardial infarction.

BACKGROUND: Percutaneous coronary intervention (PCI) for ST-elevation myocardial infarction (STEMI) is superior to fibrinolysis when performed in a timely manner in high-volume centers. Recent European trials suggest that transfer for PCI also may be superior to fibrinolysis and increase access to PCI. In the United States, transfer times are consistently long; therefore, many believe a transfer for PCI strategy for STEMI is not practical. METHODS AND RESULTS: We developed a standardized PCI-based treatment system for STEMI patients from 30 hospitals up to 210 miles from a PCI center. From March 2003 to November 2006, 1345 consecutive STEMI patients were treated, including 1048 patients transferred from non-PCI hospitals. The median first door-to-balloon time for patients <60 miles (zone 1) and 60 to 210 miles (zone 2) from the PCI center was 95 minutes (25th and 75th percentiles, 82 and 116 minutes) and 120 minutes (25th and 75th percentiles, 100 and 145 minutes), respectively. Despite the high-risk unselected patient population (cardiogenic shock, 12.3%; cardiac arrest, 10.8%; and elderly [> or =80 years of age], 14.6%), in-hospital mortality was 4.2%, and median length of stay was 3 days. CONCLUSIONS: Rapid transfer of STEMI patients from community hospitals up to 210 miles from a PCI center is safe and feasible using a standardized protocol with an integrated transfer system.

Value-Based ST-Segment-Elevation Myocardial Infarction Care Using Risk-Guided Triage and Early Discharge.

BACKGROUND: Prior studies suggest that low-risk ST-segment-elevation myocardial infarction (STEMI) patients undergoing primary percutaneous coronary intervention can be considered for early discharge. We describe the implementation of an STEMI risk score to decrease cost while maintaining optimal patient outcomes. METHODS AND RESULTS: We determined the impact of risk-guided STEMI care on healthcare value through the retrospective application of the Zwolle Risk Score to 967 patients receiving primary percutaneous coronary intervention between 2009 and 2011. Of these patients, 540 (56%) were categorized as low risk, indicating they may be safely triaged directly to a telemetry unit rather than the intensive care unit and targeted for early discharge. We subsequently developed and implemented a modified Zwolle Risk Calculator into the electronic medical record to support application of the fast-track protocol for low-risk STEMI patients. Among 549 prospective patients with STEMI, 62% were low risk, and the fast-track protocol was followed in 75% of cases. Prospective results confirmed lower rates of complications (low risk 8.3% versus high risk 38.7%; P<0.001) and in-hospital mortality (low risk 0.4% versus High risk 12.5%; P<0.001) in the low-risk cohort. Low-risk patients had a shorter median length of stay (median and [25th, 75th percentiles]: low risk 2 [2, 3] versus high risk: 3 [2, 6]; P<0.001) and lower overall costs (low risk $6720 [$5280-$9030] versus high risk $11 783 [$7953-$25 359]; P<0.001). Low-risk patients treated on-protocol had shorter median length of stay (on-protocol 2 [1, 2] versus off-protocol 2 [2, 3]; P<0.001) and hospital costs (on-protocol $6090 [$4730, $7356] versus off-protocol $11 783 [$7953, $25 359]; P<0.001) than those treated off-protocol. On-protocol low-risk patients in the prospective cohort also had lower costs and shorter length of stay than low-risk patients in the retrospective cohort (P<0.001 for both). CONCLUSIONS: In our study, risk-guided triage and discharge after primary percutaneous coronary intervention for STEMI improved healthcare value by reducing costs of care without compromising quality of care or patient outcomes.

Comparison of safety and efficacy of sirolimus-eluting stents versus bare metal stents in patients with ST-segment elevation myocardial infarction.

Sirolimus-eluting stents (SESs) are superior to bare metal stents (BMSs) for percutaneous coronary intervention, but data regarding SESs in ST-segment elevation myocardial infarction (STEMI) are limited. We investigated the clinical outcomes of patients with STEMI who were treated with SESs. We measured clinical characteristics and acute and long-term outcomes in 306 consecutive patients with STEMI who received a SES (n = 156) or a BMS (n = 150). Patients were followed for death, nonfatal reinfarction, and target vessel revascularization. Patients with SESs had a 0.6% in-hospital mortality rate versus 5.3% in patients with BMSs (p = 0.015). Six-month mortality rates were 1.9% (SES) and 10.1% (BMS, p = 0.003). At 6 months, patients with SESs were less likely to have target vessel revascularization (1.3% vs 8.1%, p = 0.005) and achieve the composite end point (3.2% vs 16.1%, p = 0.0001). No subacute thrombosis or clinical restenosis occurred in the SES group. Patients who received BMSs were older, received more stents, and had more myocardial damage, worse renal function, and lower ejection fractions than did those in the SES group. By multivariate discriminant analysis, stent type (SES vs BMS) was the most significant determinant of the 6-month composite end point (p = 0.01) and the need for target vessel revascularization (p = 0.02). In conclusion, SESs are safe and effective in STEMI at 6 months.

Percutaneous Venoarterial Extracorporeal Membrane Oxygenation for Refractory Cardiogenic Shock Is Associated with Improved Short- and Long-Term Survival.

Mortality due to refractory cardiogenic shock (RCS) exceeds 50%. Venoarterial extracorporeal membrane oxygenation (VA-ECMO) has become an accepted therapy for RCS. The aim of our study was to evaluate outcomes of patients with RCS treated with percutaneous VA-ECMO (pVA-ECMO). Retrospective review of patients supported with VA-ECMO at our institution in 2012-2013. Clinical characteristics, bleeding, vascular complications, and outcomes including survival were assessed. A total of 37 patients were supported with VA-ECMO for RCS. The majority of VA-ECMO (76%) was placed in the catheterization laboratory. Nearly half (49%) of the patients presented with acute myocardial infarction. Seven patients (19%) underwent insertion of pVA-ECMO in the setting of cardiopulmonary resuscitation with mechanical chest compression device. Median duration of support was 5 days. Index hospitalization, 30-day, and 1-year survival were 65%, 65%, and 57%, respectively. Survival rate for discharged patients was 87.5% with a median follow-up of 450 days. Refractory cardiogenic shock supported with pVA-ECMO is associated with an improved survival in patients with a traditionally poor prognosis.

Long-term follow-up of patients undergoing postconditioning during ST-elevation myocardial infarction.

Reperfusion injury may offset the optimal salvage of myocardium achieved during primary coronary angioplasty. Thus, coronary reperfusion must be combined with cardioprotective adjunctive therapies in order to optimize myocardial salvage and minimize infarct size. Forty-three patients with their first ST-elevation myocardial infarction were randomized to myocardial postconditioning or standard of care at the time of primary coronary angioplasty. Postconditioning was performed immediately upon crossing the lesion with the guide wire and consisted of four cycles of 30 s occlusion followed by 30 s of reperfusion. End-points included infarct size, myocardial perfusion grade (MPG), left-ventricular ejection fraction (LVEF), and long-term clinical events (death and heart failure). Despite similar ischemic times (≅4.5 h) (p = 0.9) a reduction in infarct size was observed among patients treated with the postconditioning protocol. Peak creatine phosphokinase (CPK), as well as its myocardial band (MB) fraction, was significantly lower in the postconditioning group when compared with the control group (CPK--control, 2,444 ± 1,928 IU/L vs. PC, 2,182 ± 1,717 IU/L; CPK-MB--control, 242 ± 40 IU/L vs. PC, 195 ± 33 IU/L; p = 0.64 and p < 0.01, respectively). EF in the postconditioning group was improved when compared with the control group (control, 43% ± 15 vs. PC, 52% ± 9; p = 0.05). After a mean follow-up of 3.4 years, a 6-point absolute difference in LVEF was still evident in the postconditioning group (p = 0.18). MPG was better among patients treated with the postconditioning protocol compared with control (2.5 ± 0.5 vs. 2.1 ± 0.6; p = 0.02). Due to the small sample size no significant differences in clinical events were detected (p value for death = 0.9; p value for heart failure = 0.2). A simple postconditioning protocol applied at the onset of mechanical reperfusion, resulted in reduction of infarct size, better epicardial and myocardial flow, and improvement in left ventricular function. The beneficial effects of postconditioning on cardiac function persist beyond 3 years.

ST-elevation myocardial infarction: which patients do quality assurance programs include?

BACKGROUND: In the United States, efforts are underway to improve timely access to percutaneous coronary intervention in ST-elevation myocardial infarction (STEMI). The Joint Commission (TJC) and the American College of Cardiology National Cardiovascular Data Registry (NCDR) have developed standardized definitions and clinical performance measures for STEMI. The purpose of this study was to determine differences in 3 quality-assurance registries for STEMI patients. METHODS AND RESULTS: STEMI patients presenting to the Minneapolis Heart Institute at Abbott Northwestern Hospital (Minneapolis, Minn) are tracked by 3 distinct quality assurance programs: NCDR, TJC, and the level 1 MI registry (a regional system for percutaneous coronary intervention in STEMI which includes transfer patients). Over 1 year, we examined consecutive STEMI patients in level 1 and compared them with individuals meeting NCDR and TJC inclusion criteria. Of 501 STEMI patients treated using the level 1 MI protocol, 422 patients had a clear culprit (402 percutaneous coronary intervention, 13 coronary artery bypass grafting, 7 medical management). In the same period, 282 patients met inclusion criteria for NCDR (56% of the level 1 population), and 66 met inclusion criteria for TJC (13% of the level 1 population). Transfer patients (n=380) accounted for 87% of the discrepancy between level 1 and TJC. Pharmacoinvasive percutaneous coronary intervention (n=102) accounted for 47% of the discrepancy between level 1 and NCDR. CONCLUSIONS: Current inclusion criteria for enrollment in STEMI registries are not uniform. This may lead to variable quality assurance outcomes for the same patient cohort and has important implications for standardized quality measurement.