Neil Brass

Temporal trends in patient and treatment delay among men and women presenting with ST-elevation myocardial infarction

BACKGROUND over the last decade, there have been major changes in the treatment of ST-elevation myocardial infarction (STEMI). Whether these have resulted in changes in sex differences in time to treatment is unknown. We examined temporal trends in time to reperfusion therapy among men and women with STEMI. METHODS the study includes 2 cohorts of STEMI patients presenting to a large metropolitan region during the periods August 24, 2000, to August 20, 2002 (Cohort1, n = 753), and August 25, 2006, to December 31, 2008 (Cohort2, n = 885). RESULTS in both cohorts, compared with men, women were significantly older and had more comorbidities. Rate of emergency medical services use among women increased from 55% in Cohort1 to 66% in Cohort2 (P = .02). Median time from symptom onset to first medical contact was 84 minutes among men and 121 minutes among women (P < .01) in Cohort1 and 59 minutes among men and 81 minutes among women (P < .01) in Cohort2. Median door-to-balloon time was significantly longer among women compared with men in Cohort2. After multivariable adjustment, female sex was associated with a 34% (or 27-minute) increase in time from symptom onset to first medical contact and with a 23% (or 13-minute) increase in time from hospital arrival to reperfusion therapy. CONCLUSIONS in the last decade, there have been significant reductions in patient and system delay, especially among women. However, women continue to have longer presentation and treatment times, suggesting that there continue to be opportunities for improvement.

Cocaine abuse and coronary artery dissection

A 33-year-old man with a history of recent cocaine use presented with dissection of the left main coronary artery extending distally to involve the left anterior descending (LAD) and circumflex arteries. He required emergency four-vessel aortocoronary bypass, which was uncomplicated.

Bridging the Gap for Nonmetropolitan STEMI Patients Through Implementation of a Pharmacoinvasive Reperfusion Strategy

BACKGROUND Timely primary percutaneous coronary intervention (PCI) is the preferred reperfusion strategy in ST-elevation myocardial infarction (STEMI). However, universal access is limited outside metropolitan centres and portends worse outcomes for rural patients. This study evaluates the outcomes of STEMI patients treated in a metropolitan and nonmetroplitan setting within Vital Heart Response, an integrated reperfusion program developed to reduce reperfusion delay in Central and Northern Alberta. METHODS From October 2006 to March 2011, data on consecutive STEMI patients was prospectively recorded. Clinical characteristics, in-hospital management, and outcomes grouped by site of presentation are described. RESULTS There were 1990 metropolitan and 1602 nonmetropolitan STEMI patients. Metropolitan were older (62.7 vs 60.4 years; P < 0.001) and had more: angina (21.2% vs 16.5%; P < 0.001), dyslipidemia (45.3% vs 39.6%; P = 0.001), and hypertension (49.9% vs 46.6%; P = 0.047). The reperfusion strategy for metropolitan and nonmetropolitan: primary PCI (57.4% vs 22.9%; P < 0.001), fibrinolysis (26.3% vs 61.2%; P < 0.001), and no reperfusion (16.3% vs 15.9%; P = 0.855). First medical contact to reperfusion was delayed in nonmetropolitan with fibrinolysis and PCI, 8 and 125 minutes. A rescue PCI or coronary angiography within 24 hours was completed in 41.4% and 46.2%, respectively. Nonmetropolitan patients had fewer deaths (4.1% vs 6.8%; P = 0.001) with no difference in the composite outcome (death, reinfraction, congestive heart failure, cardiogenic shock) (16.8% vs 15.1%; P = 0.161) or major bleeding (7.9% vs 8.0%; P = 0.951). CONCLUSIONS Systematic application of a pharmacoinvasive strategy appears to be safe and effective for patients in whom a delay in mechanical reperfusion is anticipated.

Treatment choices in elderly patients with ST: elevation myocardial infarction—insights from the Vital Heart Response registry

Background Management of elderly patients with ST elevation myocardial infarction (STEMI) is challenging and they are under-represented in trials. Accordingly, we analysed reperfusion strategies and their effectiveness in patients with STEMI ≥75 years compared to <75 years within a comprehensive inclusive registry. Methods Consecutive patients with STEMI admitted to hospital and tracked within a regional registry (2006–2011) were analysed comparing reperfusion strategy (primary percutaneous coronary intervention (PPCI), fibrinolysis and no reperfusion) between patients ≥75 vs <75 years old as well as across the reperfusion strategies in those ≥75 years. Results There were 3588 patients with STEMI with 646 (18%) ≥75 years old. Elderly patients were more likely female (46.9% vs 18.4%) and had more prior: angina (28.2% vs 17.2%), myocardial infarction (MI; 22.8% vs 13.9%), hypertension (67.6% vs 44.2%), heart failure (2.3% vs 0.3%) and atrial fibrillation (2.2% vs 0.5%) (all p<0.001). The reperfusion strategy for patients ≥75 vs <75: PPCI 45.3% vs 41.2%, fibrinolysis 24.8% vs 45.7%, and no reperfusion 29.9% vs 13.1% (p<0.001). Time from symptoms to first medical contact (median, 93 vs 78 min p=0.008) and PPCI (median, 166 vs 136 min (p<0.001) were longer for ≥75 years. In those ≥75 years outcomes by reperfusion (PPCI, fibrinolysis and none) were: in-hospital death 13.3%, 9.4% and 19.7% (p=0.018), and composite of death, recurrent-MI, cardiogenic shock and congestive heart failure 28%, 20% and 33.2% (p=0.022). Conclusions Elderly patients have more comorbidities, worst in-hospital clinical outcomes and are less likely to receive reperfusion. Acknowledging physician selection of the reperfusion strategy; outcomes appear favourable in the elderly receiving fibrinolysis.

Mode of hospital presentation in patients with non–ST-elevation myocardial infarction: Implications for strategic management

INTRODUCTION Contemporary non-ST-elevation myocardial infarction-acute coronary syndrome guidelines emphasize early-risk stratification and optimizing therapy including an invasive strategy in high-risk patients. To assess the feasibility of initiating this strategy in the prehospital environment, we examined how such patients are transported to hospital, their risk profile, and the proportion potentially eligible for such a strategy. METHODS Consecutive patients with ST-segment elevation myocardial infarction admitted in Edmonton were studied between September and November 2008 and divided according to their mode of transport to hospital: emergency medical services (EMS) versus self-presenting. Baseline characteristics, GRACE Risk Score, blinded core laboratory electrocardiogram analysis, cardiac biomarkers, in-hospital procedures, and outcomes were analyzed. RESULTS Thirty-five percent (93/263) of patients presented via EMS and often to percutaneous coronary intervention hospitals, that is, 64.5% versus 44.1% (P = .0016). They were older (75 vs 62 years, P < .001), more often female (43% vs 28.1%, P < .001), diabetic (34.4% vs 22.9%, P = .045), and hypertensive (72.0% vs 57.1%, P = .017) and had higher GRACE Risk Scores (median 166 vs 130, P < .001). Electrocardiogram analysis revealed more baseline Q waves (38.8% vs 25.5%, P = .031) and ST depression ≥2 mm (P = .027) in EMS-transported patients. Fewer EMS patients underwent cardiac catheterization (60.2% vs 88.2%, P < .001), and a paradoxical relationship existed between catheterization rates and GRACE Risk Score in the total cohort (low-risk: 93.4% vs high-risk: 59.3%, P < .001). The composite of death/re-myocardial infarction/congestive heart failure/shock was greater in EMS patients (unadjusted odds ratio 3.96, 95% CI 1.80-8.69, P = .001); these differences were attenuated after GRACE Risk Score adjustment. CONCLUSION Regional strategies using risk-based triage, early medical therapy, and timely triage to percutaneous coronary intervention centers represents an unrealized opportunity to enhance ST-segment elevation myocardial infarction care.

Myocardial Infarction as a Rare Consequence of a Snakebite Diagnosis With Novel Echocardiographic Tissue Doppler Techniques

A healthy 28-year-old man with no history of cardiac disease and no cardiac risk factors presented to the hospital 2 hours after being bitten on his right hand by his pet snake. He was in anaphylactic shock and was rapidly resuscitated with fluids, inotropic support, intramuscular antitetanus serum, and intravenous infusion of Viper-FAB, an antidote. His vital signs normalized and he was admitted to intensive care for further observation. One hour after admission, the patient’s systolic blood pressure dropped to 40 mm Hg. Intravenous noradrenaline was started. Thirty minutes later, the patient lost consciousness in association with a rhythm change to torsade de pointes. He was defibrillated with 100 J (biphasic defibrillator) to sinus rhythm. Intravenous magnesium was started, and a repeat 12-lead ECG showed a prolonged corrected QT interval at 490 ms with no ST elevation (Figure 1). An urgent echocardiogram demonstrated normal-sized left ventricle with mild hypokinesis of the anterior wall and a global left ventricular fraction of 60%. Tissue Doppler images acquired by Vivid-7 (GE Medical) …A healthy 28-year-old man with no history of cardiac disease and no cardiac risk factors presented to the hospital 2 hours after being bitten on his right hand by his pet snake. He was in anaphylactic shock and was rapidly resuscitated with fluids, inotropic support, intramuscular antitetanus serum, and intravenous infusion of Viper-FAB, an antidote. His vital signs normalized and he was admitted to intensive care for further observation. One hour after admission, the patient’s systolic blood pressure dropped to 40 mm Hg. Intravenous noradrenaline was started. Thirty minutes later, the patient lost consciousness in association with a rhythm change to torsade de pointes. He was defibrillated with 100 J (biphasic defibrillator) to sinus rhythm. Intravenous magnesium was started, and a repeat 12-lead ECG showed a prolonged corrected QT interval at 490 ms with no ST elevation (Figure 1). An urgent echocardiogram demonstrated normal-sized left ventricle with mild hypokinesis of the anterior wall and a global left ventricular fraction of 60%. Tissue Doppler images acquired by Vivid-7 (GE Medical) …

Providing Rapid Out of Hospital Acute Cardiovascular Treatment 4 (PROACT‐4)

Background Whether prehospital point‐of‐care (POC) troponin further accelerates the time to diagnosis in patients with chest pain (CP) is unknown. We conducted a randomized trial of POC‐Troponin testing in the ambulance. Methods and Results Patients with chest pain presenting by ambulance were randomized to usual care (UC) or POC‐Troponin; ST‐elevation myocardial infarction patients or those with noncardiovascular symptoms were excluded. Pre‐hospital high‐sensitivity troponin was analyzed on a POC device and available to the paramedic and emergency department (ED) staff. The final diagnosis was centrally adjudicated. The primary endpoint was time from first medical contact to discharge from ED or admission to hospital. We randomized 601 patients in 19 months; 296 to UC and 305 to POC‐Troponin. After ambulance arrival, the first troponin was available in 38 minutes in POC‐Troponin and 139 minutes in UC. In POC‐Troponin, the troponin was >0.01 ng/mL in 17.4% and >0.03 ng/mL in 9.8%. Patients spent a median of 9.0 hours from first medical contact to final disposition, and 165 (27.4%) were admitted to the hospital. The primary endpoint was shorter in patients randomized to POC‐Troponin (median 8.8 hours [6.2–10.8] compared to UC (median 9.1 hours [6.7–11.2]; P=0.05). There was no difference in the secondary endpoint of repeat ED visits, hospitalizations, or death in the next 30 days. Conclusions In this broad population of patients with CP, ambulance POC‐Troponin accelerated the time to final disposition. Enhanced and more cost‐effective early ED discharge of the majority of patients with CP calling 911 is an unrealized opportunity. Clinical Trial Registration URL: https://www.ClinicalTrials.gov/. Unique identifier: NCT01634425.

Images in cardiovascular medicine. Myocardial infarction as a rare consequence of a snakebite: diagnosis with novel echocardiographic tissue Doppler techniques.

A healthy 28-year-old man with no history of cardiac disease and no cardiac risk factors presented to the hospital 2 hours after being bitten on his right hand by his pet snake. He was in anaphylactic shock and was rapidly resuscitated with fluids, inotropic support, intramuscular antitetanus serum, and intravenous infusion of Viper-FAB, an antidote. His vital signs normalized and he was admitted to intensive care for further observation. One hour after admission, the patient’s systolic blood pressure dropped to 40 mm Hg. Intravenous noradrenaline was started. Thirty minutes later, the patient lost consciousness in association with a rhythm change to torsade de pointes. He was defibrillated with 100 J (biphasic defibrillator) to sinus rhythm. Intravenous magnesium was started, and a repeat 12-lead ECG showed a prolonged corrected QT interval at 490 ms with no ST elevation (Figure 1). An urgent echocardiogram demonstrated normal-sized left ventricle with mild hypokinesis of the anterior wall and a global left ventricular fraction of 60%. Tissue Doppler images acquired by Vivid-7 (GE Medical) …A healthy 28-year-old man with no history of cardiac disease and no cardiac risk factors presented to the hospital 2 hours after being bitten on his right hand by his pet snake. He was in anaphylactic shock and was rapidly resuscitated with fluids, inotropic support, intramuscular antitetanus serum, and intravenous infusion of Viper-FAB, an antidote. His vital signs normalized and he was admitted to intensive care for further observation. One hour after admission, the patient’s systolic blood pressure dropped to 40 mm Hg. Intravenous noradrenaline was started. Thirty minutes later, the patient lost consciousness in association with a rhythm change to torsade de pointes. He was defibrillated with 100 J (biphasic defibrillator) to sinus rhythm. Intravenous magnesium was started, and a repeat 12-lead ECG showed a prolonged corrected QT interval at 490 ms with no ST elevation (Figure 1). An urgent echocardiogram demonstrated normal-sized left ventricle with mild hypokinesis of the anterior wall and a global left ventricular fraction of 60%. Tissue Doppler images acquired by Vivid-7 (GE Medical) …

Longitudinal treatment patterns with ADP receptor inhibitors after myocardial infarction: Insights from the Canadian Observational AntiPlatelet sTudy

BACKGROUND After myocardial infarction (MI) treated with percutaneous coronary intervention (PCI), guidelines recommend dual antiplatelet therapy (DAPT) with aspirin and an ADP receptor inhibitor (ADPri) for at least 1year. However, whether real-world Canadian practice patterns reflect this recommendation is unknown. METHODS We studied 2175 MI patients treated with PCI and discharged from 26 Canadian hospitals between 12/2011 and 05/2013 in the Canadian Observational Antiplatelet sTudy (COAPT). Hierarchical Cox proportional hazard regression modeling was used to determine baseline demographic and clinical factors associated with duration of ADPri therapy post-discharge. RESULTS At index-hospitalization discharge, 1597 (73%) patients were treated with clopidogrel, 220 (10%) with prasugrel, and 358 (17%) with ticagrelor. ADPri was discontinued prior to 1year in 474 (21.8%) patients; discontinuation rates were lowest for patients discharged on prasugrel (17.7%), compared with clopidogrel (22.5%) or ticagrelor (21.0%), (log rank test, p=0.03). In addition to regional variability, factors associated with shorter ADPri duration included older age, low body weight, Killip III/IV heart failure, atrial fibrillation, ticagrelor on discharge, and bare metal stent use, while longer ADPri duration was associated with history of prior MI. CONCLUSIONS One in five PCI-treated MI patients did not complete Canadian guideline-recommended 1-year course of ADPri treatment. Premature ADPri discontinuation was most strongly associated with factors that increase the risk of bleeding. Further study is required to assess the clinical implications of premature ADPri discontinuation on patient outcomes.

Suburban cardiac screening: Improving access to specialist services within a primary care network

This article evaluates a cardiac screening program by analyzing wait times and exploring associations between administratively tracked variables and confirmed cardiac diagnosis. The findings indicate that the wait times for specialist consultation are shorter than previously reported in Alberta and age and sex have the strongest associations with a confirmed cardiac diagnosis.