M. Bilal Iqbal

Radial versus femoral access is associated with reduced complications and mortality in patients with non-ST-segment-elevation myocardial infarction: an observational cohort study of 10,095 patients.

Background—Compared with transfemoral access, transradial access (TRA) for percutaneous coronary intervention is associated with reduced risk of bleeding and vascular complications. Studies suggest that TRA may reduce mortality in patients with ST-segment–elevation myocardial infarction. However, there are few data on the effect of TRA on mortality, specifically, in patients with non–ST-segment–elevation myocardial infarction. Methods and Results—We analyzed 10 095 consecutive patients with non–ST-segment–elevation myocardial infarction treated with percutaneous coronary intervention between 2005 and 2011 in all 8 tertiary cardiac centers in London, United Kingdom. TRA was a predictor for reduced bleeding (odds ratio=0.21; 95% confidence interval [CI]: 0.08–0.57; P=0.002), access-site complications (odds ratio=0.47; 95% CI: 0.23–0.95; P=0.034), and 1-year mortality (hazard ratio [HR]=0.72; 95% CI: 0.54–0.94; P=0.017). Between 2005 and 2007, TRA did not appear to reduce mortality at 1 year (HR=0.81; 95% CI: 0.51–1.28; P=0.376), whereas between 2008 and 2011, TRA conferred survival benefit at 1 year (HR=0.65; 95% CI: 0.46–0.92; P=0.015). The mortality benefit with TRA at 1 year was not seen at the low-volume centers (HR=0.80; 95% CI: 0.47–1.38; P=0.428) but specifically seen in the high volume radial centers (HR=0.70; 95% CI: 0.51–0.97; P=0.031). In propensity-matched analyses, TRA remained a predictor for survival at 1 year (HR=0.60; 95% CI: 0.42–0.85; P=0.005). Instrumental variable analysis demonstrated that TRA conferred mortality benefit at 1-year with an absolute mortality reduction of 5.8% (P=0.039). Conclusions—In this analysis of patients with non–ST-segment–elevation myocardial infarction, TRA appears to be a predictor for survival. Furthermore, the evolving learning curve, experience, and expertise may be important factors contributing to the prognostic benefit conferred with TRA.

Predictors of Survival and Favorable Functional Outcomes After an Out-of-Hospital Cardiac Arrest in Patients Systematically Brought to a Dedicated Heart Attack Center (from the Harefield Cardiac Arrest Study)

Despite advances in cardiopulmonary resuscitation (CPR), survival remains low after out-of-hospital cardiac arrest (OOHCA). Acute coronary ischemia is the predominating precipitant, and prompt delivery of patients to dedicated facilities may improve outcomes. Since 2011, all patients experiencing OOHCA in London, where a cardiac etiology is suspected, are systematically brought to heart attack centers (HACs). We determined the predictors for survival and favorable functional outcomes in this setting. We analyzed 174 consecutive patients experiencing OOHCA from 2011 to 2013 brought to Harefield Hospital-a designated HAC in London. We analyzed (1) all-cause mortality and (2) functional status using a modified Rankin scale (mRS 0 to 6, where mRS0-3(+) = favorable functional status). The overall survival rates were 66.7% (30 days) and 62.1% (1 year); and 54.5% had mRS0-3(+) at discharge. Patients with mRS0-3(+) had reduced mortality compared to mRS0-3(-): 30 days (1.2% vs 72.2%, p <0.001) and 1 year (5.3% vs 77.2%, p <0.001). Multivariate analyses identified lower patient comorbidity, absence of cardiogenic shock, bystander CPR, ventricular tachycardia/ventricullar fibrillation as initial rhythm, shorter duration of resuscitation, prehospital advanced airway, absence of adrenaline and inotrope use, and intra-aortic balloon pump use as predictors of mRS0-3(+). Consistent predictors of increased mortality were the presence of cardiogenic shock, advanced airway use, increased duration of resuscitation, and absence of therapeutic hypothermia. A streamlined delivery of patients experiencing OOHCA to dedicated facilities is associated with improved functional status and survival. Our study supports the standardization of care for such patients with the widespread adoption of HACs.

Outcome of 1051 Octogenarian Patients With ST‐Segment Elevation Myocardial Infarction Treated With Primary Percutaneous Coronary Intervention: Observational Cohort From the London Heart Attack Group

Background ST‐segment elevation myocardial infarction is increasingly common in octogenarians, and optimal management in this cohort is uncertain. This study aimed to describe the outcomes of octogenarians with ST‐segment elevation myocardial infarction treated by primary percutaneous coronary intervention. Methods and Results We analyzed 10 249 consecutive patients with ST‐segment elevation myocardial infarction treated with primary percutaneous coronary intervention between 2005 and 2011 at 8 tertiary cardiac centers across London, United Kingdom. The primary end point was all‐cause mortality at a median follow‐up of 3 years. In total, 1051 patients (10.3%) were octogenarians, with an average age of 84.2 years, and the proportion increased over the study period (P=0.04). In‐hospital mortality (7.7% vs 2.4%, P<0.0001) and long‐term mortality (51.6% vs 12.8%, P<0.0001) were increased in octogenarians compared with patients aged <80 years, and age was an independent predictor of mortality in a fully adjusted model (hazard ratio 1.07, 95% CI 1.07–1.09, P<0.0001). Time‐stratified analysis revealed an increasingly elderly and more complex cohort over time. Nonetheless, long‐term mortality rates among octogenarians remained static over time, and this may be attributable to improved percutaneous coronary intervention techniques, including significantly higher rates of radial access and lower bleeding complications. Variables associated with bleeding complications were similar between octogenarian and younger cohorts. Conclusions In this large registry, octogenarians undergoing primary percutaneous coronary intervention had a higher rate of complications and mortality compared with a younger population. Over time, octogenarians undergoing primary percutaneous coronary intervention increased in number, age, and complexity. Nevertheless, in‐hospital outcomes were reasonable, and long‐term mortality rates were static.

Contemporary trends in cardiogenic shock: Incidence, intra-aortic balloon pump utilisation and outcomes from the London Heart Attack Group:

Background: Cardiogenic shock remains a major cause of morbidity and mortality in patients with ST-segment elevation myocardial infarction. We aimed to assess the current trends in cardiogenic shock management, looking specifically at the incidence, use of intra-aortic balloon pump therapy and outcomes in patients with ST-segment elevation myocardial infarction treated with primary percutaneous coronary intervention. Methods and results: We undertook an observational cohort study of 21,210 ST-segment elevation myocardial infarction patients treated between 2005–2015 at the eight Heart Attack Centres in London, UK. Patients’ details were recorded at the time of the procedure into local databases using the British Cardiac Intervention Society percutaneous coronary intervention dataset. There were 1890 patients who presented with cardiogenic shock. The primary outcome was all-cause mortality at a median follow-up of 4.1 years (interquartile range: 2.2–5.8 years). Increasing rates of cardiogenic shock were seen over the course of the study with consistently high mortality rates of 45–70%. A total of 685 patients underwent intra-aortic balloon pump insertion during primary percutaneous coronary intervention for cardiogenic shock with decreasing rates over time. Those patients undergoing intra-aortic balloon pump therapy were younger, more likely to have poor left ventricular function and less likely to have had previous percutaneous coronary intervention compared to the control group. Procedural success rates were similar (86.0% vs 87.1%, p=0.292) although crude, in-hospital major adverse cardiac event rates were higher (43.8% vs 33.7%, p<0.0001) in patients undergoing intra-aortic balloon pump therapy. Kaplan-Meier analysis demonstrated significantly higher mortality rates in patients receiving intra-aortic balloon pump therapy (50.9% intra-aortic balloon pump vs 39.9% control, p<0.0001) during the follow-up period. After multivariate Cox analysis (hazard ratio 1.04, 95% confidence interval 0.62–1.89) and the use of propensity matching (hazard ratio: 1.29, 95% confidence interval: 0.68–1.45) intra-aortic balloon pump therapy was not associated with mortality. Conclusion: Cardiogenic shock treated by percutaneous coronary intervention is increasing in incidence and remains a condition associated with high mortality and limited treatment options. Intra-aortic balloon pump therapy was not associated with a long-term survival benefit in this cohort and may be associated with increased early morbidity.

Intra-Aortic Balloon Pump Counterpulsation in the Post-Resuscitation Period is Associated with Improved Functional Outcomes in Patients Surviving an Out-of-Hospital Cardiac Arrest: Insights from a Dedicated Heart Attack Centre.

BACKGROUND Despite advances in cardiopulmonary resuscitation, functional survival remains low after out-of-hospital cardiac arrest (OOHCA). Intra-aortic balloon pump (IABP) therapy has recently been shown to augment cerebral blood flow. Whether IABP therapy in the post-resuscitation period improves functional outcomes is unknown. METHODS We analysed 174 consecutive patients who were successfully resuscitated from an OOHCA between 2011-2013 at Harefield Hospital, London. We analysed functional status at discharge and mortality up to one year. RESULTS A total of 55 patients (32.1%) received IABP therapy. Comparing those receiving IABP with those not receiving IABP, there was no difference in favourable functional status at discharge (49.1% vs. 57.1%, p=0.321); and mortality at one year (45.5% vs. 35.5%, p=0.164). Multivariable analyses identified IABP therapy as a strong independent predictor for favourable functional status at discharge (OR=7.51, 95% CI: 2.15-26.14, p=0.002) and this association was maintained in propensity-score adjusted analyses (OR=9.90, 95% CI: 2.11-46.33, p=0.004) and inverse probability treatment weighted analyses (OR=10.84, 95% CI: 2.75-42.69, p<0.001). However, IABP therapy was not an independent predictor for mortality at one year (HR=0.93, 95% CI: 0.52-1.65, p=0.810) and this was confirmed in both propensity-score adjusted and inverse probability treatment weighted analyses. CONCLUSIONS In this observational analysis of patients surviving an OOHCA, the use of IABP therapy in the post-resuscitation period was associated with improved functional outcomes. This warrants further evaluation in larger prospective studies.

The prognostic significance of incomplete revascularization and untreated coronary anatomy following percutaneous coronary intervention: An analysis of 6,755 patients with multivessel disease

More than half of the patients undergoing percutaneous coronary intervention (PCI) have multivessel disease. Whether complete revascularization impacts long‐term mortality or whether selected patients or those with specific coronary anatomy benefit from complete revascularization is unclear.

Time-Trend Analyses of Bleeding and Mortality After Primary Percutaneous Coronary Intervention During Out of Working Hours Versus In-Working Hours An Observational Study of 11 466 Patients

Background—Primary percutaneous coronary intervention (PPCI) is the treatment of choice for ST-segment–elevation myocardial infarction. Resources are limited during out of working hours (OWH). Whether PPCI outside working hours is associated with worse outcomes and whether outcomes have improved over time are unknown. Methods and Results—We analyzed 11 466 patients undergoing PPCI between 2004 and 2011 at all 8 tertiary cardiac centers in London, United Kingdom. We defined working hours as 9 AM to 5 PM (Monday to Friday). We analyzed in-hospital bleeding and all-cause mortality ⩽3 years, comparing OWH versus in-working hours. A total of 7494 patients (65.3%) were treated during OWH. Multivariable analyses demonstrated that PPCI during OWH was not a predictor for bleeding (odds ratio, 1.47; 95% confidence interval [CI], 0.97–2.24; P=0.071) or 3-year mortality (hazard ratio, 1.11; 95% CI, 0.94–1.32; P=0.20). This was confirmed in propensity-matched analyses. Time-stratified analyses demonstrated that PPCI during OWH was a predictor for bleeding (odds ratio, 2.00; 95% CI, 1.06–3.80; P=0.034) and 3-year mortality during 2005 to 2008 (hazard ratio, 1.23; 95% CI, 1.00–1.50; P=0.050), but this association was lost during 2009 to 2011. During 2005 to 2008, transradial access was predominantly used during in-working hours and PPCI during OWH was predictive of reduced transradial access use (odds ratio, 0.83; 95% CI, 0.71–0.98; P=0.033), but this association was lost during 2009 to 2011. Conclusions—In this study of unselected patients with ST-segment–elevation myocardial infarction, PPCI during OWH versus in-working hours had comparable bleeding and mortality. Time-stratified analyses demonstrated a reduction in adjusted bleeding and mortality during OWH over time. This may reflect the improved service provision, but the increased adoption of transradial access during OWH may also be contributory.

Mid-to-long term mortality following surgical versus percutaneous coronary revascularization stratified according to stent subtype: An analysis of 6,682 patients with multivessel disease

Background Studies comparing coronary artery bypass graft (CABG) and percutaneous coronary intervention (PCI) have largely been performed in the bare-metal stent (BMS) and first-generation drug eluting stent (F-DES) era. Second-generation DES (S-DES) have shown improved outcomes when compared to F-DES, but data comparing CABG with PCI using S-DES is limited. We compared mortality following CABG versus PCI for patients with multivessel disease and analyzed different stent types. Methods A total of 6,682 patients underwent multivessel revascularization at Harefield Hospital, UK. We stratified CABG patients into single arterial graft (SAG) or multiple arterial grafts (MAG); and PCI patients into BMS, F-DES or S-DES groups. We analyzed all-cause mortality at 5 years. Results 4,388 patients had CABG (n[SAG] = 3,358; n[MAG] = 1,030) and 2,294 patients had PCI (n[BMS] = 416; n[F-DES] = 752; n[S-DES] = 1,126). PCI had higher 5-year mortality with BMS (HR = 2.27, 95% CI:1.70–3.05, p<0.001); F-DES (HR = 1.52, 95% CI:1.14–2.01, p = 0.003); and S-DES (HR = 1.84, 95% CI:1.42–2.38, p<0.001). This was confirmed in inverse probability treatment weighted analyses. When adjusting for both measured and unmeasured factors using instrumental variable analyses, PCI had higher 5-year mortality with BMS (Δ = 15.5, 95% CI:3.6,27.5, p = 0.011) and FDES (Δ = 16.5, 95% CI:6.6,26.4, p<0.001), but had comparable mortality with CABG for PCI with SDES (Δ = 0.9, 95% CI: -9.6,7.9, p = 0.844), and when exclusively compared to CABG patients with SAG (Δ = 0.4, 95% CI: -8.0,8.7, p = 0.931) or MAG (Δ = 4.6, 95% CI: -0.4,9.6, p = 0.931). Conclusions In this real-world analysis, when adjusting for measured and unmeasured confounding, PCI with SDES had comparable 5-year mortality when compared to CABG. This warrants evaluation in adequately-powered randomized controlled trials.

The prognostic impact of revascularization strategy in acute myocardial infarction and cardiogenic shock: Insights from the British Columbia Cardiac Registry

In patients with acute myocardial infarction (AMI) and cardiogenic shock (CS), percutaneous coronary intervention (PCI) of the culprit vessel is associated with improved outcomes. A large majority of these patients have multivessel disease (MVD). Whether or not PCI of non‐culprit disease in the acute setting improves outcomes continues to be debated. We evaluated the prognostic impact of revascularization strategy for patients presenting with AMI and CS.

Reply: The Effect of Survivor Bias on Observational Analyses of Staged PCI in STEMI Patients

We thank Dr. Giri and colleagues for interest in our recent paper [(1)][1]. They raise an important issue of survivor bias, which as correctly pointed out, is a limitation to all observational analyses that have addressed multivessel disease in ST-elevation myocardial infarction. To address survivor