Impact of Postprocedural Graft Flow on Outcomes Following Chronic Total Occlusion Intervention in Postcoronary Artery Bypass Graft Patients: A Detailed Angiographic Analysis.

Chronic total occlusions (CTOs) are frequent in patients with previous coronary artery bypass graft (CABG) surgery. Percutaneous coronary intervention (PCI) is the usual revascularization strategy. Whether or not the presence of a graft on a CTO vessel and post-PCI graft patency impacts outcomes after CTO-PCI is unknown. We sought to evaluate the impact of post-PCI graft patency on the durability of CTO-PCI. In total, 259 patients with previous CABG who underwent CTO-PCI in 12 international centers in 2019 to 2023 were categorized into "grafted" and "ungrafted" groups based on the presence of graft on a CTO vessel. The grafted group was subdivided into "graft-occluded" and "graft-patent" groups, depending on graft patency. The primary end points were (1) technical success rate, (2) target vessel failure, and (3) CTO failure rates at 1 year. CTO failure was defined as target vessel revascularization and/or significant in-stent restenosis. A total of 199 patients (77%) were in the grafted group. Grafted CTOs showed higher complexity and lower technical success rates (70% vs 80%, p = 0.004) than nongrafted CTOs. Of the grafted CTOs, 140 (70%) were in the grafted-occluded group and 59 (30%) were in the grafted-patent group. The technical success was lower in the former group (65% vs 81%, p = 0.022). An occluded graft was an independent predictor of technical failure (odds ratio 2.04, 95% confidence interval 1.03 to 4.76, p = 0.049) and persistent post-PCI graft patency was a strong independent predictor of CTO failure at 1 year (hazard ratio 5.6, 95% confidence interval 1.2 to 27.5, log-rank p = 0.033). In conclusion, in patients with previous CABG who underwent CTO-PCI, post-PCI graft patency was a significant predictor of CTO failure.

The Impact of Pre-Procedural Renal Impairment on Outcomes Following Percutaneous Coronary Intervention: An Analysis of 45,287 Patients From the British Columbia Cardiac Registry.

BACKGROUND: Renal disease confers a strong independent risk for morbidity and mortality after percutaneous coronary intervention (PCI). We evaluated the relationship between baseline pre-procedural renal function and outcomes following PCI. METHODS: We examined 45,287 patients who underwent PCI in British Columbia. We evaluated all-cause mortality and target vessel revascularisation (TVR) at 2 years. Pre-procedural renal impairment was categorised by creatinine clearance (CrCl, mL/min): CrCl≥90 (n=14,876), 90>CrCl≥60 (n=10,219), 60>CrCl≥30 (n=14,876), 30>CrCl≥0 (n=2,594) and dialysis (n=579). RESULTS: Declining CrCl values less than 60 mL/min were progressively associated with greater mortality: 60>eGFR≥30 (HR=2.01, 95% CI 1.71-2.37, p<0.001); 30>eGFR≥0 (HR=4.10, 95% CI 3.39-4.95, p<0.001); and dialysis (HR=6.22, 95% CI 5.07-7.63, p<0.001). A reduction in eGFR was not associated with TVR in non-dialysis patients. However, dialysis was a strong independent predictor for TVR (HR=1.69, 95% CI 1.37-2.08, p<0.001). This was confirmed in propensity-matched analyses where, dialysis was strongly associated with TVR (HR=1.53, 95% CI 1.24-1.89, p<0.001). This association was consistently seen in stratified analyses for diabetic versus non-diabetic patients; stent length >30 mm versus <30 mm; stent diameter >3 mm versus <3 mm; and receipt of bare metal stents versus drug-eluting stents. CONCLUSIONS: This study indicates the association with declining renal function and mortality in patients undergoing PCI. Whilst renal disease was not associated with increased TVR in non-dialysis patients, dialysis-dependence was a strong independent predictor for increased TVR.

Complete revascularization in stable multivessel coronary artery disease: A real world analysis from the British Columbia Cardiac Registry.

BACKGROUND: More than half of patients undergoing percutaneous coronary intervention (PCI) have multivessel disease (MVD). The prognostic significance of PCI in stable patients has recently been debated, but little data exists about the potential benefit of complete revascularization (CR) in stable MVD. We investigated the prognostic benefit of CR in patients undergoing PCI for stable disease. METHODS: We compared CR versus incomplete revascularization (IR) in 8,436 patients with MVD. The primary outcome was all-cause mortality at 5 years. RESULTS: A total of 1,399 patients (17%) underwent CR during the index PCI procedure for stable disease. CR was associated with lower mortality (6.2 vs. 10.7%, p < .001) and lower repeat revascularization at 5 years (12.7 vs. 18.4%, p < .001). Multivariable-adjusted analyses indicated that CR was associated with lower mortality (HR = 0.73, 95% CI: 0.58-0.91, p = .005) and repeat revascularization at 5 years (HR = 0.78, 95% CI: 0.66-0.93, p = .005). These findings were also confirmed in propensity-matched cohorts. Subgroup analyses indicated that CR conferred survival in older patients, male patients, absence of renal disease, greater angina (CCS Class III-IV) and heart failure (NYHA Class III-IV) symptoms, and greater burden of coronary disease. In sensitivity analyses where patients with subsequent repeat revascularization events were excluded, CR remained a strong predictor for lower mortality (HR = 0.69, 95% CI: 0.54-0.89, p = .004). CONCLUSIONS: In this study of stable patients with MVD, CR was an independent predictor of long-term survival. This benefit was specifically seen in higher risk patient groups and indicates that CR may benefit selected stable patients with MVD.

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

BACKGROUND: 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. METHODS: We compared culprit vessel intervention (CVI) versus multivessel intervention in 649 patients with AMI, CS, and MVD enrolled in the British Columbia Cardiac Registry. We evaluated mortality at 30 days and 1 year. RESULTS: CVI was associated with lower mortality at 30 days (23.7% vs. 34.5%, P = 0.004) and 1 year (32.6% vs. 44.3%, P = 0.003). CVI was an independent predictor for survival at 30 days (HR = 0.63, 95% CI: 0.45-0.88, P = 0.009) and 1 year (HR = 0.72, 95% CI: 0.54-0.96, P = 0.027). These findings were confirmed in propensity-matched cohorts. Subgroup analyses indicated that CVI was associated with lower mortality in patients aged <80 years; non-diabetics; and those presenting with ST-elevation MI. When analyzing non-culprit anatomy, PCI of non-culprit LAD disease was associated with higher 1-year mortality (HR = 1.51, 95% CI: 1.13-2.01, P = 0.006), primarily with non-culprit proximal LAD disease (HR = 1.82, 95% CI: 1.20-2.76, P = 0.005). However, PCI of non-culprit non-proximal LAD, LCx, and RCA disease was not associated with mortality. CONCLUSIONS: In patients with AMI and CS, a strategy of CVI appears to be associated with lower mortality. These findings are consistent with recently published randomized-controlled trial data.

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

BACKGROUND: 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. METHODS: A total of 14,452 patients underwent PCI between 2004 and 2015 at Harefield Hospital, UK. Of these, 7,076 patients had multivessel disease. We excluded 321 patients with left main-stem stenosis ≥50%, with 6,755 patients included in the analysis (936 patients had complete revascularization). RESULTS: The unadjusted 3-year mortality rates were lower with complete revascularization (10.8% vs 13.1%, P = 0.047). However, multivariable-adjusted analyses indicated that complete revascularization was not independently associated with mortality (HR = 1.01, 95% CI: 0.78-1.31, P = 0.939). These findings were unchanged when addressing measured confounding using propensity-matched analyses (HR = 1.16, 95% CI: 0.81-1.65, P = 0.417) and inverse probability treatment weighted analyses (HR = 1.01, 95% CI: 0.77-1.33, P = 0.950); and unmeasured confounding using instrumental variable analyses (Δ = 0.9%, 95% CI: -2.5%, 4.3%, P = 0.958). There was no association with mortality and untreated LAD disease (HR = 0.92, 95% CI: 0.72-1.17, P = 0.482) and LCx disease (HR = 0.90, 95% CI: 0.74-1.10, P = 0.999). However, untreated proximal LAD disease (HR = 1.23, 95% CI: 1.06-1.51, P = 0.045) and RCA disease (HR = 1.36, 95% CI: 1.08-1.65, P = 0.007) was associated with increased mortality, particularly in patients with ST-elevation acute coronary syndrome (STEACS). CONCLUSIONS: In this study of unselected patients undergoing PCI, complete revascularization did not confer a mortality benefit. However, the presence of untreated proximal LAD and RCA disease was prognostic in patients with STEACS. Thus, complete revascularization may be considered in select patient groups with anatomical subsets of coronary disease.

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.

A feasibility and safety study of intracoronary hemodilution during primary coronary angioplasty in order to reduce reperfusion injury in myocardial infarction.

OBJECTIVES: We designed a pilot study to evaluate safety and feasibility of an inexpensive and simple approach to intracoronary hemodilution during primary angioplasty (PPCI) to reduce reperfusion injury. INTRODUCTION: Early revascularization in acute myocardial infarction decreases infarct size and improves outcomes. However, abrupt restoration of coronary flow results in myocardial reperfusion injury and increased final infarct size. Dilution of coronary blood during revascularization may help reduce this damage. If proved effective, such an approach would need to be simple and suitable for widespread adoption. METHODS: Ten patients presenting with STEMI underwent intracoronary dilution with room temperature Hartmann's solution delivered through the guiding catheter during primary angioplasty (PPCI). Infusion of perfusate began prior to crossing the occluded artery with the guidewire, continuing until 10 min after completion of the balloon and stenting procedure. Infusion was briefly interrupted for contrast injection and pressure monitoring. The outcome measures were safety, including intracoronary temperature reduction and volume of intracoronary perfusate infused, and technical feasibility. RESULTS: There were no significant symptomatic, hemodynamic, ECG ST/T segment or rhythm changes observed during perfusate administration. The median (interquartile range) volume of perfusate administered was 550 mL (350-725 mL) and the median intracoronary temperature reduction observed was 3.4°Celsius. Myocardial salvage was 0.54 (0.43-0.65). CONCLUSIONS: Transcatheter intracoronary hemodilution with room temperature perfusate during PPCI is feasible and appears safe. Such a strategy is simple and inexpensive, with potential to be widely applied. Further mechanistic and subsequent outcome powered studies are required to evaluate whether this strategy can reduce reperfusion injury in STEMI.

Comparison of Outcomes of Coronary Artery Bypass Grafting Using Internal Mammary Graft Versus Percutaneous Coronary Intervention for Isolated Proximal Left Anterior Descending Narrowing.

There are limited contemporary studies comparing coronary artery bypass grafting (CABG) and percutaneous coronary intervention (PCI) for isolated proximal left anterior descending (LAD) disease. Increasing stent length and decreasing stent diameters are associated with increased risk of restenosis and adverse outcomes after PCI. Whether these parameters influence outcomes when comparing CABG and PCI is unclear. We compared CABG and PCI in 3,473 patients who underwent revascularization for isolated proximal LAD disease from 2004 to 2015 at Harefield Hospital, UK; 3,078 patients (89%) had PCI and 384 patients had CABG (11%). We analyzed all-cause mortality at 3 years. The unadjusted mortality rates were similar (PCI vs CABG: 9.5% vs 7.0%, p = 0.109). PCI was associated with comparable mortality (hazard ratio [HR] 1.15, 95% confidence interval [CI] 0.70 to 1.89, p = 0.593), even when stratified to bare-metal stents (HR 1.58, 95% CI 0.89 to 2.80, p = 0.121); first-generation drug-eluting stents (FDES; HR 1.16, 95% CI 0.67 to 2.02, p = 0.597); and second-generation DES (SDES; HR 0.98, 95% CI 0.53 to 1.82, p = 0.946). Stent diameters did not influence outcomes, but PCI was associated with higher mortality when stent length ≥30 mm (HR 2.12, 95% CI 1.12 to 4.03, p = 0.022). There was a linear association between stent length and mortality, and for every 1-mm increase in stent length, the 3-year mortality increased by 0.32%. In conclusion, for patients with isolated proximal LAD disease, PCI and CABG were associated with similar mortality. Increasing stent length was progressively associated with worse outcomes with PCI. For longer segments of disease requiring stent lengths ≥30 mm, CABG may be associated with better outcomes.

Culprit Vessel Versus Multivessel Versus In-Hospital Staged Intervention for Patients With ST-Segment Elevation Myocardial Infarction and Multivessel Disease: Stratified Analyses in High-Risk Patient Groups and Anatomic Subsets of Nonculprit Disease.

OBJECTIVES: This study evaluated revascularization strategies for patients with ST-segment elevation myocardial infarction (STEMI) and multivessel disease. BACKGROUND: In patients with STEMI and multivessel disease, it is unclear whether multivessel intervention (MVI), culprit vessel intervention (CVI) only (CVI-O) or CVI with staged revascularization (CVI-S) is associated with improved outcomes. Whether MVI at primary percutaneous coronary intervention may benefit specific patient groups is unclear. METHODS: We compared revascularization strategies (MVI, CVI-O, and CVI-S) in 6,503 patients with STEMI and multivessel disease enrolled in the British Columbia Cardiac Registry (2008 to 2014). We evaluated all-cause mortality and repeat revascularization at 2 years. RESULTS: Compared with MVI, CVI-O (hazard ratio [HR]: 0.78; 95% confidence interval [CI]: 0.64 to 0.97; p = 0.023) and CVI-S (HR: 0.55; 95% CI: 0.36 to 0.82; p = 0.004) were associated with lower mortality. Comparing CVI-O with CVI-S, CVI-S was associated with lower mortality (HR: 0.65; 95% CI: 0.47 to 0.91; p = 0.013). Compared with MVI, CVI-O was associated with increased repeat revascularization (HR: 1.25; 95% CI: 1.02 to 1.54; p = 0.036). Comparing CVI-O versus CVI-S, CVI-S was associated with lower repeat revascularization (HR: 0.64; 95% CI: 0.46 to 0.90; p = 0.012). CVI was associated with lower mortality in the presence of nonculprit left circumflex artery disease (HR: 0.63; 95% CI: 0.45 to 0.89; p = 0.011) and right coronary artery disease (HR: 0.66; 95% CI: 0.44 to 0.99; p = 0.050), but not nonculprit left anterior descending artery disease (HR: 0.83; 95% CI: 0.54 to 1.28; p = 0.399). CONCLUSIONS: In patients with STEMI undergoing primary percutaneous coronary intervention, a strategy of CVI-S seems to be associated with lower mortality and repeat revascularization rates. However, MVI may be considered in selected patients and in the setting of nonculprit left anterior descending artery disease. These findings warrant prospective evaluation in large adequately powered randomized controlled trials.

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.

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.

Long-term outcomes following drug-eluting stents versus bare metal stents for primary percutaneous coronary intervention: A real-world analysis of 11,181 patients from the british columbia cardiac registry.

BACKGROUND: Drug eluting stents (DES) are associated with reduced risk of restenosis when compared with bare metal stents (BMS). Their use in ST-elevation myocardial infarction (STEMI) is debated, owing to concerns about stent thrombosis. There are limited real-world data comparing DES versus BMS in STEMI. We conducted an observational analysis in this setting and rigorously adjusted for treatment selection bias. METHODS: We analyzed 11,181 consecutive patients with acute STEMI who received either DES or BMS during 2008-2014 in the British Columbia Cardiac Registry. We analyzed target vessel revascularization (TVR) and mortality at 2 years. RESULTS: Multivariable-adjusted, propensity-matched and inverse probability-treatment weighted analyses found DES to be associated with early and late survival up to 2 years but not TVR. However, when adjusting for measured and unmeasured confounders, instrumental variable (IV) analyses demonstrated that DES use was associated with reduced TVR up to 2 years (Δ = -6.7%, 95% CI: -10.0%, -3.4%, P < 0.001). DES use was not associated with mortality at 1 year (Δ = -2.3%, 95% CI: -5.0%, 0.4%, P = 0.100) but associated with reduced mortality at 2 years (Δ = -5.4%, 95% CI: -8.3%, -2.5%, P < 0.001). Stratified IV analyses indicated that this long-term survival benefit was largely attributable to the second generation DES. CONCLUSIONS: In this study of patients with STEMI, when adjusting for measured and unmeasured factors, DES use was associated with reduced TVR and long-term survival beyond 1 year. This long-term survival was largely attributable to the second generation DES. These real-world data are reassuring and support the use of DES for STEMI. © 2016 Wiley Periodicals, Inc.

Intra-Aortic Balloon Pump Counterpulsation during Primary Percutaneous Coronary Intervention for ST-Elevation Myocardial Infarction and Cardiogenic Shock: Insights from the British Columbia Cardiac Registry.

BACKGROUND: Cardiogenic shock complicating ST-elevation myocardial infarction (STEMI) is associated with significant morbidity and mortality. In the primary percutaneous coronary intervention (PPCI) era, randomized trials have not shown a survival benefit with intra-aortic balloon pump (IABP) therapy. This differs to observational data which show a detrimental effect, potentially reflecting bias and confounding. Without robust and valid risk adjustment, findings from non-randomized studies may remain biased. METHODS: We compared long-term mortality following IABP therapy in patients with cardiogenic shock undergoing PPCI during 2008-2013 from the British Columbia Cardiac Registry. We addressed measured and unmeasured confounding using propensity score and instrumental variable methods. RESULTS: A total of 12,105 patients with STEMI were treated with PPCI during the study period. Of these, 700 patients (5.8%) had cardiogenic shock. Of the patients with cardiogenic shock, 255 patients (36%) received IABP therapy. Multivariable analyses identified IABP therapy to be associated with increased mortality up to 3 years (HR = 1.67, 95% CI:1.20-2.67, p<0.001). This association was lost in propensity-matched analyses (HR = 1.23, 95% CI: 0.84-1.80, p = 0.288). When addressing measured and unmeasured confounders, instrumental variable analyses demonstrated that IABP therapy was not associated with mortality at 3 years (Δ = 16.7%, 95% CI: -12.7%, 46.1%, p = 0.281). Subgroup analyses demonstrated IABP was associated with increased mortality in non-diabetics; patients not undergoing multivessel intervention; patients without renal disease and patients not having received prior thrombolysis. CONCLUSIONS: In this observational analysis of patients with STEMI and cardiogenic shock, when adjusting for confounding, IABP therapy had a neutral effect with no association with long-term mortality. These findings differ to previously reported observational studies, but are in keeping with randomized trial data.

Prognostic Significance of Polymer Coatings in Zotarolimus-Eluting Stents.

Polymer coatings on drug-eluting stents (DES) serve as a vehicle for delivery of antirestenotic drugs. Whether they influence outcomes for contemporary DES is unknown. The evolution of polymer coatings for zotarolimus-eluting stents (ZES) provides a natural experiment that facilitates such analysis. The Resolute ZES (R-ZES) uses the same antirestenotic drug as the Endeavor ZES (E-ZES) but has a more biocompatible polymer with enhanced drug release kinetics. However, there are limited data on the real-world comparative efficacy of R-ZES and the preceding E-ZES. Thus, we analyzed 17,643 patients who received either E-ZES or R-ZES from 2008 to 2014 from the British Columbia Cardiac Registry. A total of 9,869 patients (56%) received E-ZES and 7,774 patients (44%) received R-ZES. Compared with E-ZES, R-ZES was associated with lower 2-year mortality (4.1% vs 6.4%, p <0.001) and 2-year target vessel revascularization (TVR; 6.8% vs 10.7%, p <0.001). R-ZES use was an independent predictor of lower mortality rate and TVR. This was confirmed in propensity-matched analyses for 2-year mortality (hazard ratio [HR] 0.59, 95% CI 0.49 to 0.71, p <0.001) and 2-year TVR (HR 0.86, 95% CI 0.75 to 0.98, p = 0.032). Instrumental variable analyses demonstrated R-ZES to be associated with lower 2-year mortality (Δ = -2.2%, 95% CI -4.3% to -0.2%, p = 0.032) and 2-year TVR (Δ = -3.3% to 95% CI -6.1% to -0.7%, p = 0.015). Acknowledging the limitations of observational analyses, this study has shown that R-ZES was associated with lower long-term TVR and mortality. These data are reassuring for the newer R-ZES and demonstrate how polymer coatings may influence the clinical performance of DES with wider implications for future DES development and design.