Imad J. Nadra

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.

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.

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.

Variation in practice and concordance with guideline criteria for length of stay after elective percutaneous coronary intervention.

Considerable variability remains as regards the appropriate and safe length of stay after elective PCI. We performed a survey of interventional cardiologists to identify current views on appropriate and safe length of stay after PCI.

Embolic protection device use and its association with procedural safety and long-term outcomes following saphenous vein graft intervention: An analysis from the British Columbia Cardiac registry

Embolic protection devices (EPDs) have been designed and introduced to reduce distal embolization and peri‐procedural myocardial infarction during saphenous vein graft (SVG) intervention. Current guidelines give a class I recommendation to EPD use during SVG intervention when technically feasible. However, the routine use of these devices has recently been debated.

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.

Radial artery pseudoaneurysms after transradial cardiac catheterisation

BACKGROUND Although uncommon, radial artery access site complications are likely to become more frequent with the increased adoption of transradial cardiac catheterisation. There is a lack of data regarding the incidence and clinical features of radial artery pseudoaneuryms. We aimed to describe the incidence, clinical features and management of radial artery pseudoaneurysms in a high-volume transradial cardiac catheterisation centre. PATIENTS AND METHODS We performed a search of the Vancouver Island Health Authority medical imaging database from 1st Jan 2008 to April 2012 looking for all radial and femoral artery pseudoaneuryms occurring after cardiac catheterisation. Hospital charts were reviewed to determine patient and procedural characteristics as well as management and outcome. RESULTS There were a total of 14,968 coronary procedures performed over the four year search period, of which 13,216 (88%) were trans-radial. The incidence of radial artery pseudoaneurysm after cardiac catheterisation was 0.08%, and did not differ between transradial diagnostic angiography and PCI (0.07% vs 0.08%; P = 0.90). In contrast, the incidence of femoral artery pseudoaneurysm was higher, at 1.4% (P < 0.0001). Patients with radial pseudoaneurysms were generally elderly, with a median age of 77 years, and there were no gender differences. Only one patient had received a glycoprotein IIb/IIIa inhibitor, whilst two received warfarin post-procedure. The majority of cases (80%) were treated with surgical repair. CONCLUSIONS We have demonstrated that radial artery pseudoaneuryms are a rare but important complication of transradial cardiac catheterisation, with patients generally requiring surgical repair. Most patients were elderly, but surprisingly only a minority were anti-coagulated with warfarin.

Successful Transcatheter Aortic Valve Replacement in a Patient With a Sinus of Valsalva Aneurysm

Transcatheter aortic valve replacement (TAVR) is increasingly being used to treat patients with severe aortic stenosis who are either deemed to be inoperable or at prohibitive surgical risk [(1)][1]. Both operator experience and devices have evolved over time, as have the indications for valve

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.

RENAL FUNCTION-BASED CONTRAST DOSING TO DEFINE “PROGNOSTIC” CONTRAST DOSE LIMITS FOR PERCUTANEOUS CORONARY INTERVENTION – THE PROGNOSTIC IMPLICATION OF THE CONTRAST VOLUME: GLOMERULAR FILTRATION RATIO IN 44,082 PATIENTS FROM THE BRITISH COLUMBIA CARDIAC REGISTRY

Background: Renal function-based contrast dosing to limit renal injury following percutaneous coronary intervention (PCI) has been studied but its prognostic relevance is unknown. We evaluated the contrast volume: glomerular filtration rate (GFR) ratio (R) to define “prognostic” limits for

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