Outcomes of Patients With ST-Elevation Myocardial Infarction Receiving and Not Receiving Reperfusion Therapy: The Importance of Examining All Patients.

BACKGROUND: Hospitals treating patients with ST-elevation myocardial infarction (STEMI) may show good results with reperfusion treatment (fibrinolysis or primary percutaneous coronary intervention [PPCI]), but a comprehensive evaluation should factor in outcomes of patients with STEMI who do not receive reperfusion. We compared outcomes of patients receiving and not receiving reperfusion within a complete system of STEMI care by hospital type: PPCI centres, fibrinolysis centres, centres that only transfer for PPCI, and centres providing a mix of fibrinolysis and PPCI transfer. METHODS: All patients presenting to 82 Quebec hospitals with characteristic symptoms, a final diagnosis of acute myocardial infarction, and core-laboratory confirmed STEMI over two 6-month periods were studied. RESULTS: Of the total 3731 patients with STEMI, 2918 (78.2%) received reperfusion treatment (81% PPCI, 19% fibrinolysis); 813 (21.8%) did not. For reperfusion-treated patients, 30-day mortality was 5.4% in PPCI centres, 5.4% in fibrinolysis centres, 6.9% in transfer PPCI centres, and 6.0% in mixed centres (P = 0.55). For untreated patients, 30-day mortality was 15.7% (PPCI centres), 16.1% (fibrinolysis centres), 21.8% (transfer PPCI), and 24.6% (mixed) (P = 0.08). Adjusted mortality odds ratios for all patients were 1.00 (PPCI centres), 1.50 (95% CI: 0.97-2.32; fibrinolysis centres), 1.30 (0.95-1.78; transfer PPCI centres), and 1.58 (1.09-2.29; mixed centres). PPCI was within recommended delays in 35.4%, 11.9%, and 1.2% of PPCI, transfer, and mixed centres, respectively. CONCLUSIONS: Mixed centres had the highest crude and adjusted all-patient 30-day STEMI mortality. Relatively good outcomes of reperfusion-treated patients, despite long treatment delays, can misrepresent overall performance if untreated patients are not examined.

Clinical Profiles Related to Timing of Death, Including In-Hospital Deaths Before Admission, in Patients With ST-Elevation Myocardial Infarction.

Patients with ST-elevation myocardial infarction (STEMI) who die in hospital before inpatient admission are generally not included in clinical studies and registries, and the clinical profiles of patients who die earlier versus later are not well defined. We aimed to characterize all patients with STEMI who arrived at emergency departments in the province of Quebec (Canada) based on inpatient admission status and when they died. All patients who presented with symptoms and core laboratory-confirmed STEMI or left bundle branch block during 6 months in 82 hospitals in Quebec were included. Death certificates were used to identify nonadmitted deaths. Of the 2017 patients with STEMI, 340 (16.9%) died within 1 year. Of the latter, 63 (18.5%) were nonadmitted deaths (group A), 179 (52.6%) were deaths after admission but within 30 days (group B), and 98 (28.8%) were deaths after 30 days to 1 year (group C). Group A was younger and most often hemodynamically unstable, followed for both features by B then C. Earliest presentation from symptom onset and most frequent ambulance use were found in group A, followed by B, then C. Presenting electrocardiogram (ECG) features were most severe in A, then B, then C (more arrhythmias, more anterior STEMI, more leads with ST elevation, and higher ST elevation). Patients who died earliest had the least frequency of previous myocardial infarction, coronary revascularization, vascular disease, and heart failure, and the least noncardiac co-morbidity. In conclusion, patients with STEMI dying in hospital before inpatient admission contributed substantially to overall STEMI mortality. Although dying patients who presented earlier had severer presenting clinical profiles, they were paradoxically younger and had less co-morbidity. Previous co-morbidities may favor adaptive protective mechanisms on initial presentation with STEMI.

Comparison of outcomes of ambulance users and nonusers in ST elevation myocardial infarction.

In a systematic province-wide evaluation of care and outcomes of ST elevation myocardial infarction (STEMI), we sought to examine whether a previously documented association between ambulance use and outcome remains after control for clinical risk factors. All 82 acute care hospitals in Quebec (Canada) that treated at least 30 acute myocardial infarctions annually participated in a 6-month evaluation in 2008 to 2009. Medical record librarians abstracted hospital chart data for consecutive patients with a discharge diagnosis of myocardial infarction who presented with characteristic symptoms and met a priori study criteria for STEMI. Linkage to administrative databases provided outcome data (to 1 year) and co-morbidities. Of 1,956 patients, 1,222 (62.5%) arrived by ambulance. Compared with nonusers of an ambulance, users were older, more often women, and more likely to have co-morbidities, low systolic pressure, abnormal heart rate, and a higher Thrombolysis In Myocardial Infarction risk index at presentation. Ambulance users were less likely to receive fibrinolysis or to be sent for primary angioplasty (78.5% vs 83.2% for nonusers, p = 0.01), although if they did, treatment delays were shorter (p <0.001). The 1-year mortality rate was 18.7% versus 7.1% for nonusers (p <0.001). Greater mortality persisted after adjusting for presenting risk factors, co-morbidities, reperfusion treatment, and symptom duration (hazard ratio 1.56, 95% confidence interval 1.30 to 1.87). In conclusion, ambulance users with STEMI were older and sicker than nonusers. Mortality of users was substantially greater after adjustment for clinical risk factors, although they received faster reperfusion treatment overall.

Impact of ECG findings and process-of-care characteristics on the likelihood of not receiving reperfusion therapy in patients with ST-elevation myocardial infarction: results of a field evaluation.

BACKGROUND: Many patients with ST-elevation myocardial infarction (STEMI) do not receive reperfusion therapy and are known to have poorer outcomes. We aimed to perform the first population-level, integrated analysis of clinical, ECG and hospital characteristics associated with non-receipt of reperfusion therapy in patients with STEMI. METHODS AND RESULTS: This systematic evaluation of STEMI care in 82 hospitals in Quebec included all patients with a discharge diagnosis of myocardial infarction, presenting with characteristic symptoms and an ECG showing STEMI as attested by at least one of two study cardiologists or left bundle branch block (LBBB). Excluding LBBB, an ECG was considered a definite STEMI diagnosis if both cardiologists scored 'certain STEMI' and ambiguous if one scored 'uncertain' or 'not STEMI'. Centers were classified according to accessibility to primary percutaneous coronary intervention (PPCI): 1) on-site PPCI; 2) routine transfer for PPCI; 3) varying mix of PPCI transfer and on-site fibrinolysis; and 4) routine on-site fibrinolysis. Of 3730 STEMI/LBBB patients, 812 (21.8%) did not receive reperfusion therapy. In multivariate analysis, likelihood of no reperfusion therapy was a function of PPCI accessibility (odds ratio [OR] for fibrinolysis versus PPCI centers = 3.1; 95% CI: 2.2-4.4), presence of LBBB (OR = 24.1; 95% CI: 17.8-32.9) and an ECG ambiguous for STEMI (OR = 4.1; 95% CI: 3.3-5.1). When the ECG was ambiguous, likelihood of no reperfusion therapy was highest in hospitals most distant from PPCI centers. CONCLUSIONS: ECG diagnostic ambiguity, LBBB and PPCI accessibility are important predictors of not receiving reperfusion therapy, suggesting opportunities for improving outcomes.

Transfer of patients with ST-elevation myocardial infarction for primary percutaneous coronary intervention: a province-wide evaluation of "door-in to door-out" delays at the first hospital.

BACKGROUND: Interhospital transfer of patients with ST-elevation myocardial infarction (STEMI) for primary percutaneous coronary intervention (PPCI) is associated with longer delays to reperfusion, related in part to turnaround ("door in" to "door out," or DIDO) time at the initial hospital. As part of a systematic, province-wide evaluation of STEMI care, we examined DIDO times and associations with patient, hospital, and process-of-care factors. METHODS AND RESULTS: We performed medical chart review for STEMI patients transferred for PPCI during a 6-month period (October 1, 2008, through March 31, 2009) and linked these data to ambulance service databases. Two core laboratory cardiologists reviewed presenting ECGs to identify left bundle-branch block and, in the absence of left bundle-branch block, definite STEMI (according to both cardiologists) or an ambiguous reading. Median DIDO time was 51 minutes (25th to 75th percentile: 35-82 minutes); 14.1% of the 988 patients had a timely DIDO interval (≤30 minutes as recommended by guidelines). The data-to-decision delay was the major contributor to DIDO time. Female sex, more comorbidities, longer symptom duration, arrival by means other than ambulance, arrival at a hospital not exclusively transferring for PPCI, arrival at a center with a low STEMI volume, and an ambiguous ECG were independently associated with longer DIDO time. When turnaround was timely, 70% of patients received timely PPCI (door-to-device time ≤90 minutes) versus 14% if turnaround was not timely (P<0.0001). CONCLUSIONS: Benchmark DIDO times for STEMI patients transferred for PPCI were rarely achieved. Interventions aimed at facilitating the transfer decision, particularly in cases of ECGs that are difficult to interpret, are likely to have the best impact on reducing delay to reperfusion.

Computerized interpretation of the prehospital electrocardiogram: predictive value for ST segment elevation myocardial infarction and impact on on-scene time.

INTRODUCTION: Computerized interpretation of the prehospital electrocardiogram (ECG) is increasingly being used in the basic life support (BLS) ambulance setting to reduce delays to treatment for patients suspected of ST segment elevation myocardial infarction (STEMI). OBJECTIVES: To estimate 1) predictive values of computerized prehospital 12-lead ECG interpretation for STEMI and 2) additional on-scene time for 12-lead ECG acquisition. METHODS: Over a 2-year period, 1,247 ECGs acquired by primary care paramedics for suspected STEMI were collected. ECGs were interpreted in real time by the GE-Marquette 12SL ECG analysis program. Predictive values were estimated with a bayesian latent class model incorporating the computerized ECG interpretations, consensus ECG interpretations by study cardiologists, and hospital diagnosis. On-scene time was compared for ambulance-transported patients with (n  =  985) and without (n  =  5,056) prehospital ECGs who received prehospital aspirin and/or nitroglycerin. RESULTS: The computer's positive and negative predictive values for STEMI were 74.0% (95% credible interval [CrI] 69.6-75.6) and 98.1% (95% CrI 97.8-98.4), respectively. The sensitivity and specificity were 69.2% (95% CrI 59.0-78.5) and 98.9% (95% CrI 98.1-99.4), respectively. Prehospital ECGs were associated with a mean increase in on-scene time of 5.9 minutes (95% confidence interval 5.5-6.3). CONCLUSIONS: The predictive values of the computerized prehospital ECG interpretation appear to be adequate for diversion programs that direct patients with a positive result to hospitals with angioplasty facilities. The estimated 26.0% chance that a positive interpretation is false is likely too high for activation of a catheterization laboratory from the field. Acquiring prehospital ECGs does not substantially increase on-scene time in the BLS setting.

Should eligibility for heart transplantation be a requirement for left ventricular assist device use? Recommendations based on a systematic review.

Left ventricular assist devices (LVADs) are used in chronic end-stage heart failure as "bridge to transplantation" (BTT) and, more recently, for transplant-ineligible patients as "destination therapy" (DT). We reviewed the evidence on clinical effects and cost-effectiveness of 2 types of continuous-flow LVADs (HeartMate II [HM II] and HeartWare), for BTT and DT patients. We systematically searched the scientific literature (January 2008-June 2012) and identified 14 clinical studies (approximately 2900 HM II and approximately 200 HeartWare patients), and 3 economic evaluations (HM II) using simulation models. Data were, however, limited to 2-3 studies per outcome. We made policy recommendations on the basis of our systematic review. Although complications after implantation are frequent, LVAD therapy is often highly effective across transplantation eligibility status and device, with 1-year survival reaching 86% for BTT and 78% for DT (compared with 25% for medical therapy). Neither BTT nor DT currently meet traditional cost-effectiveness limits in models using historical data, although BTT is standard practice for a limited number of patients in many regions. We found that BTT and DT as implantation strategies tend to be no longer mutually exclusive. We conclude that evidence is sufficient to support LVAD use, regardless of transplantation eligibility status, as long as patients are carefully selected and program infrastructure and budget are adequate. However, evidence gaps, limitations in economic models, and the lack of Canadian data point to the importance of mandatory, systematic monitoring of LVAD use and outcomes.

Information on myocardial ischemia and arrhythmias added by prehospital electrocardiograms.

BACKGROUND: The prehospital electrocardiogram (ECG) allows earlier identification of acute ST-segment elevation myocardial infarction (STEMI). Its utility for detection of other acute cardiac events, as well as for transient ST-segment abnormalities no longer present when the first hospital ECG is performed, is not well characterized. OBJECTIVE: We sought to examine whether the prehospital ECG adds supplemental information to the first ECG obtained in hospital, by comparing data on possible cardiac ischemia and arrhythmias provided by the two ECGs, in ambulance patients later diagnosed as having cardiac disorders, including STEMI. METHODS: Ambulance personnel acquired 12-lead ECGs for patients suspected of having an acute ischemic event, prior to transport to hospital. The first emergency department 12-lead ECG was provided by medical records at the receiving hospital, and the principal hospital diagnosis for the event was extracted from chart data. Two cardiologists, blinded to the hospital diagnosis, provided their consensus interpretation of 1,209 pairs of ECGs, noting the presence or absence of specific abnormalities on each tracing. RESULTS: Among the 82 patients who had an eventual hospital diagnosis of STEMI, the study cardiologists identified 71 with ST-segment elevations on the ECGs they examined. The vast majority of these (97%) were observed on both ECGs, but the prehospital ECG showed ST-segment elevation for two additional patients (3%). No additional instances were seen only on the hospital ECG. Among the 116 patients with a hospital diagnosis of non-ST-segment elevation myocardial infarction (NSTEMI), the cardiologists identified 36 with ST-segment depressions: 28 (78%) of these were present on both ECGs, seven (19%) only on the prehospital ECG, and one (3%) only on the hospital ECG. Among the 567 patients with any cardiac hospital diagnosis, the cardiologists identified 87 with arrhythmias: 73 (84%) on both ECGs, 12 (14%) only on the prehospital ECG, and two (2%) only on the hospital ECG. CONCLUSIONS: Beyond identifying ST-segment elevation earlier, prehospital ECGs detect important transient abnormalities, information not otherwise available from the first emergency department ECG. These data can expedite diagnosis and clinical management decisions among patients suspected of having an acute cardiac event. The prehospital ECG should be fully integrated into emergency medicine practice.

Transcatheter aortic valve implantation: recommendations for practice based on a multidisciplinary review including cost-effectiveness and ethical and organizational issues.

Transcatheter aortic valve implantation (TAVI) is a relatively new technology for the treatment of severe and symptomatic aortic valve stenosis. TAVI offers an alternative therapy for patients unable to be treated surgically because of contraindications or severe comorbidities. It is being rapidly dispersed in Canada, as it is worldwide. The objective of this article is to present our recommendations for the use of TAVI, based on a multidisciplinary evaluation of recently published evidence. We systematically searched and summarized published data (2008-2011) on benefits, risks, and cost-effectiveness of TAVI. We also examined ethical issues and organizational aspects of delivering the intervention. We discussed the soundness and applicability of our recommendations with clinical experts active in the field. The published TAVI results for high-risk and/or inoperable patients are promising in terms of survival, function, quality of life, and cost-effectiveness, although we noted large variability in the survival rates at 1 year and in the frequency of important adverse outcomes such as stroke. Until more data from randomized controlled trials and registries become available, prudence and discernment are necessary in the choice of patients most likely to benefit. Patients need to be well-informed about gaps in the evidence base. Our recommendations support the use of TAVI in the context of strict conditions with respect to patient eligibility, the patient selection process, organizational requirements, and the tracking of patient outcomes with a mandatory registry.

Summary: evaluation of the evidence on the HeartMate II® and HeartWare® ventricular assist devices for the treatment of chronic end-stage heart failure

CONTEXT: Heart failure is a complex syndrome that arises when the heart is incapable of pumping enough blood to respond to the metabolic needs of the body. Heart failure is often caused by defective contraction and relaxation of the myocardium, accompanied by elevated cardiac filling pressure. It represents the final stage of a number of cardiovascular diseases. Characterized by limitation in activities of daily living and progressive exhaustion at rest, heart failure is a disabling and life-threatening condition. Severe heart failure, defined as class IV using the functional classification scheme of the New York Heart Association (NYHA), is associated with a 1-year mortality of about 50%. Heart failure is a major public health problem, associated with high rates of morbidity and mortality. It is estimated that more than 80,000 people are affected in Quebec, and the incidence of heart failure is expected to increase as a result of ageing of the population. More than 75% of patients suffering from heart failure in

Summary: Transcatheter aortic valve implantation: Evaluation of the evidence and synthesis of organizational issues

CONTEXT: Aortic valvular stenosis, or narrowing of the valve orifice, is a progressive disease that generally affects patients over the age of 65 years in Western countries and is usually caused by degenerative calcification. Aortic stenosis causes increasing resistance against the ejection of blood from the left ventricle towards the aorta. After symptoms appear (dyspnea, angina, syncope), the disease rapidly progresses causing severe limitation of physical capacity, heart failure, and high risk of mortality. Aortic stenosis represents the third most common cardiovascular disease among adults and the most frequent cardiac valve illness among elderly persons in the industrialized world. Its prevalence is estimated at at 2.8% in the population aged 75 and older in the United States. In Quebec, the number of octogenarians will double to about 780,000 persons by 2035, representing about 9% of the total population. Aortic stenosis will thus become more frequent and is expected to have an increasingly important impact on the Quebec health care system. Until recently, the only effective therapy for severe or symptomatic aortic stenosis was surgical valve replacement, but about a third of elderly patients can be refused this procedure due to their health status or aortic anatomy, which renders surgery too risky. In 2002, a percutaneous technique for implanting an aortic valve was developed, allowing the delivery by catheter and deployment of an aortic valve bioprosthesis, without recourse to open-heart surgery. Since then, the number of transcatheter aortic valve implantations (TAVIs) carried out worldwide has increased at a rapid rate. However, there are no Canadian clinical practice guidelines specific to TAVI, and the criteria for selection of patients raise important questions. Currently in Quebec, several institutions either have already set up a TAVI program or are in the process of doing so. A narrative review of the literature up to 2009 and an analysis of the Quebec experience was published in 2010 by a working group of the Réseau québécois de cardiologie tertiaire (RQCT). Following the release of this document, the ministère de la Santé et des Services sociaux (MSSS) recommended that this procedure be used only for patients who cannot be treated by traditional surgical methods due to an excessive risk of complications and be offered only by university hospitals or institutes with experienced multidisciplinary teams (performing a minimum of 30 procedures a year). Also, the MSSS gave the Institut national d'excellence en santé et en services sociaux (INESSS) the mandate to perform an evaluation of TAVI. OBJECTIVES OF THIS EVALUATION: 1. Synthesize, via a systematic review, the recent evidence on effectiveness, safety and economic issues related to TAVI using the Cribier-Edwards / Edwards SAPIEN or CoreValve bioprostheses for adult patients with severe, symptomatic aortic stenosis, with an emphasis on clinical results at 1 year; and to 2. Synthesize, via a narrative review, the principal organizational aspects of delivering this procedure, including the selection of patients before implantation and key considerations concerning ethics and the patient's perspective. METHODS: A systematic search of the scientific literature published between January 2008 and January 2011 was carried out using bibliographic databases, 2008 being the year when clinical results on mortality at 1 year began to become available. Given the relative lack of publications from registries, on quality of life and regarding economic issues, we also selected several oral presentations from scientific conferences. Using primary research articles and registry reports that provided survival data at 1 year as the main source of information, we examined clinical results for TAVI patients at 30 days and at 1 year. In order to summarize issues pertaining to organizational aspects and patient eligibility, we retrieved relevant information from the following sources: 1) the most recent expert consensus documents from North America and Europe; 2) health technology assessment (HTA) reports published between 2008 and 2010, and the 2011 update of a report by the National Institute for Health and Clinical Excellence (NICE); 3) relevant articles retrieved from our literature search; and 4) a key research article and accompanying editorial, published in June 2011, concerning cohort A of the PARTNER randomized controlled trial. RESULTS: In the systematic review of clinical results, 17 studies met our selection criteria: 13 were research studies (1 randomized controlled trial, 4 controlled cohort studies, 8 case series), and 4 were analyses of registries (2 national, 2 from industry), which can be considered as case series. Most studies were from outside North America. In the clinical trial (PARTNER B cohort), 179 patients were randomized to transfemoral TAVI, and 179 were randomized to medical treatment (most of the patients in this group also underwent balloon aortic valvuloplasty (BAV) for aggravation of their aortic stenosis). We also retained 3 HTA reports and 2 systematic review. In each of the 17 studies, the patients eligible for TAVI were considered either inoperable, not suitable for surgery or at high surgical risk. In almost every study, it was indicated that patient selection was based on the consensus decision of a multidisciplinary team. In general, TAVI patients were elderly (with a mean age of at least 81 years) and the majority were in New York Heart Association (NYHA) class 3 or 4, but the extent of surgical risk varied greatly across studies.

Underuse of prehospital strategies to reduce time to reperfusion for ST-elevation myocardial infarction patients in 5 Canadian provinces.

OBJECTIVE: Timely reperfusion therapy for ST-elevation myocardial infarction (STEMI) is an important determinant of outcome, yet targets for time to treatment are frequently unmet in North America. Prehospital strategies can reduce time to reperfusion. We sought to determine the extent to which emergency medical services (EMS) use these strategies in Canada. METHODS: We carried out a cross-sectional survey in 2007 of ground EMS operators in British Columbia, Alberta, Ontario, Quebec and Nova Scotia. We focused on the use of 4 prehospital strategies: 1) 12-lead electrocardiogram (ECG), 2) routine expedited emergency department (ED) transfer of STEMI patients (from a referring ED to a percutaneous coronary intervention [PCI] centre), 3) prehospital bypass (ambulance bypass of local EDs to transport patients directly to PCI centres) and 4) prehospital fibrinolysis. RESULTS: Ninety-seven ambulance operators were surveyed, representing 15 681 paramedics serving 97% of the combined provincial populations. Of the operators surveyed, 68% (95% confidence interval [CI] 59%-77%) had ambulances equipped with 12-lead ECGs, ranging from 40% in Quebec to 100% in Alberta and Nova Scotia. Overall, 47% (95% CI 46%-48%) of paramedics were trained in ECG acquisition and 40% (95% CI 39%-41%) were trained in ECG interpretation. Only 18% (95% CI 10%-25%) of operators had prehospital bypass protocols; 45% (95% CI 35%-55%) had protocols for expedited ED transfer. Prehospital fibrinolysis was available only in Alberta. All EMS operators in British Columbia, Alberta and Nova Scotia used at least 1 of the 4 prehospital strategies, and one-third of operators in Ontario and Quebec used 0 of 4. In major urban centres, at least 1 of the 3 prehospital strategies 12-lead ECG acquisition, bypass or expedited transfer was used, but there was considerable variation within and across provinces. CONCLUSION: The implementation of widely recommended prehospital STEMI strategies varies substantially across the 5 provinces studied, and relatively simple existing technologies, such as prehospital ECGs, are underused in many regions. Substantial improvements in prehospital services and better integration with hospital-based care will be necessary in many regions of Canada if optimal times to reperfusion, and associated outcomes, are to be achieved.

Organizing health services for patients with chronic pain: when there is a will there is a way.

SETTING: Due to its magnitude as a health problem, its associated burden, and the viability of modes of intervention, chronic pain (CP) should be considered a priority within health care systems. The lives of many patients with CP are devastated by this problem and health care professionals have a responsibility to assist them in reducing their suffering. Countries, regions, and systems differ considerably with regard to how they organize, administer, and finance services for CP patients. OBJECTIVE: In this review, we highlight initiatives in three jurisdictions--France, Australia, and the Veterans' Health Administration in the United States--which demonstrate that when there is a will there is a way to change health care services for patients with CP. This work is a synopsis of a health technology assessment report we completed on behalf of the Quebec Health Services and Technology Assessment Agency (http://www.aetmis.gouv.qc.ca) at the request of the Ministry of Health and Social Services in Quebec, Canada, to inform policymakers at various levels of the health care system. DESIGN: A literature search of published and unpublished "gray" literature was used to identify organizational themes according to structure, process, and outcome elements of health care services. For each theme, literature was reviewed in a qualitative manner; in addition, "real world" information was sought from example jurisdictions that have prioritized management of CP. Our conclusions point to key issues to consider when organizing health services for CP patients.