Development and validation of a clinical risk score to predict mortality after percutaneous coronary intervention.

OBJECTIVE: To develop and validate a contemporary clinical risk score to predict mortality after percutaneous coronary intervention (PCI). METHODS: Using data collected from patients undergoing PCI at the South Yorkshire Cardiothoracic Centre, Sheffield, UK, between January 2007 and September 2013, a risk score was developed to predict mortality. Logistic regression was used to evaluate the effect of each variable upon 30-day mortality. A backwards stepwise logistic regression model was then used to build a predictive model. The results were validated both internally and externally with data from Manchester Royal Infirmary, UK. 30-Day mortality status was determined from the UK Office of National Statistics. RESULTS: The development data set comprised 6522 patients from Sheffield. Five risk factors, including cardiogenic shock, procedural urgency, history of renal disease, diabetes mellitus and age, were statistically significant to predict 30-day mortality. The risk score was validated internally on a further 3290 patients from Sheffield and externally on 3230 patients from Manchester. The discrimination of the model was high in the development (C-statistic=0.82, 95% CI 0.79 to 0.85), internal (C-statistic=0.81, 95% CI 0.76 to 0.86) and external (C statistics=0.90, 95% CI 0.87 to 0.93) cohorts. There was no significant difference between observed and predicted mortality in any group. CONCLUSION: This contemporary risk score reliably predicts 30-day mortality after PCI using a small number of clinical variables obtainable prior to the procedure, without knowledge of the coronary anatomy.

Residual SYNTAX score after PCI for triple vessel coronary artery disease: quantifying the adverse effect of incomplete revascularisation.

AIMS: There is some evidence to suggest that incompleteness of coronary artery revascularisation after PCI is associated with inferior outcomes. The SYNTAX score was developed as a tool to quantify the extent of coronary artery disease in the SYNTAX study. We aimed to use this score to quantify the completeness of revascularisation after PCI (the "residual SYNTAX score") and to determine its impact upon mortality. METHODS AND RESULTS: We studied 240 consecutive patients with native three-vessel disease who underwent PCI between 2003 and 2008. SYNTAX scores prior to, and after, PCI were calculated, the difference (ΔSYNTAX) being a measure of the relative completeness of revascularisation. Median follow-up was 2.6 (1.2-3.2) years; 21% of patients were surgical turndowns, and 38% were non-elective. A residual (rSYNTAX) score of zero (full revascularisation) was achieved in 40% and median rSYNTAX was 3.5 (0-10.9). At final follow-up reduced mortality was found in patients with rSYNTAX 0 vs. others (2.5 vs. 12%, respectively, p=0.003) and for those with rSYNTAXmedian (3 vs. 11%, p=0.003). rSYNTAX was an independent predictor of mortality in a multivariate analysis, whereas baseline SYNTAX score was not. CONCLUSIONS: The residual SYNTAX score is a useful method to quantify incomplete revascularisation in patients undergoing PCI for 3VD. Complete revascularisation (rSYNTAX=0) is achieved in only a minority and, for them, the mortality rate is low.

Impact of incomplete revascularization in patients undergoing PCI for unprotected left main stem stenosis.

INTRODUCTION: Percutaneous revascularization of patients with multivessel and left main stem (LMS) disease may be incomplete and the impact of this is not well reported and may influence outcome. In this study we assessed the role of completeness of revascularization upon outcome after PCI for unprotected left main stem (uLMS) PCI in the "real world." MATERIALS AND METHOD: Consecutive patients (n = 353) with uLMS disease were treated by PCI by a single operator with a policy of maximal feasible revascularization between 2000 and 2011. The SYNTAX score was calculated before and after PCI (residual SYNTAX score) to gauge the completeness of revascularization. The endpoints were mortality and repeat revascularization. RESULTS: Mean age was 69 ± 11 years, baseline SYNTAX score was 33.4 ± 15, 53% were nonelective, 10% were in cardiogenic shock, and 45% were not surgical candidates. LMS bifurcation was involved in 74% and 2.0 ± 0.9 other vessels were diseased. Complete revascularization was achieved in 49% and was associated with reduced mortality compared with incomplete, at 30 days [5(2.9%) v 23(13%)], 1 year [9(5%) v 34(19%)], and 3 years [14(8%) v 46(26%)]; all P < 0.0001). Median rSYNTAX score was 1(0-11), 1-year survival for the lowest, middle and highest tertiles of rSYNTAX were 1.7%, 3.1% and 7.3% (P < 0.0001), respectively. In multivariate analysis postprocedure rSYNTAX score independently predicted outcome but preprocedural SYNTAX score did not. CONCLUSIONS: For unselected patients with uLMS treated by PCI, completeness of revascularization is associated with superior survival. The rSYNTAX score, a novel index of completeness of revascularization, independently predicts survival. Baseline SYNTAX score does not.

Simultaneous kissing drug-eluting stents to treat unprotected left main stem bifurcation disease: medium term outcome in 150 consecutive patients.

AIMS: Percutaneous coronary intervention (PCI) is increasingly being used to treat left main stem (LMS) coronary artery disease. Disease at the LMS bifurcation is technically challenging to treat, and there is no consensus as to the best method. We previously described experimental and initial clinical results with the simultaneous kissing stents (SKS) technique in a small series using drug-eluting stents (DES). We now report our results in a larger cohort with long-term follow-up. METHODS AND RESULTS: We treated 150 consecutive, unselected patients with unprotected bifurcation LMS with SKS using DES. The patients' mean age was 67 years, 70% were male, 45% were non-elective and 35% were not surgical candidates. The New York Risk Score estimate of in-hospital mortality was (median) 0.7% (IQR 0.3-3.9%), logistic EuroSCORE 3.3% (1.3-11.9%) and angiographic SYNTAX score 20 (15-27). SKS were deployed in 99.3% of cases, and DES in 97%. There was no emergency CABG. The mortality rate at one year was 11.3% and at two years 12.7%. The (ischaemia-driven) target lesion revascularisation rate was 4.3% at one year and 6.2% at two years. CONCLUSIONS: The SKS technique for treating ULMS bifurcation disease is simple, feasible, effective and durable in treating "all-comers" with LMS bifurcation disease. It is a two-stent technique worthy of consideration at the LMS bifurcation.

Novel use of a pericardium-covered stent graft to treat bulky coronary artery thrombus.

OBJECTIVES: We studied the acute safety and feasibility of a pericardium-covered stent (PCS) in the obliteration of massive coronary thrombus. BACKGROUND: Thrombus is frequently encountered in the setting of acute myocardial infarction, and conventional pharmacological and aspiration approaches are not always successful in dispersing or removing it, especially when it is very substantial. METHODS: We treated nine patients (10 lesions) in the setting of an acute coronary syndrome characterized by the presence of substantial (TIMI grade 3-4) thrombus in a large caliber native coronary artery, persisting after conventional treatment, with percutaneous implantation of an equine PCS graft. Nine of 10 lesions were in large right coronary arteries. RESULTS: Deployment was successful in nine of 10 lesions. In all nine cases, the filling defect was immediately eliminated and there was restoration or maintenance of TIMI grade 3 blood flow. There was one in-hospital stent thrombosis in a 56-year-old male, who had only received aspirin due to a coexistent stroke. This patient underwent successful repeat percutaneous intervention but died later of complications of the stroke. There were no 30-day events, and medium-term follow-up continues. CONCLUSIONS: A PCS graft is a potentially useful device to treat massive thrombus burden in the setting of acute coronary syndrome. A larger study is warranted.

Simultaneous kissing stent technique to treat left main stem bifurcation disease.

BACKGROUND: While several endovascular techniques have been developed for treating arterial bifurcation lesions, there is, as yet, no single, widely accepted technique for treating left main stem (LMS) bifurcation lesions with stents. The simultaneous kissing stent (SCS) technique seems particularly suited for such lesions. The authors describe a consecutive cohort of patients with LMS bifurcation stenosis treated with this technique and present mechanistic insights from a porcine model. METHODS: Thirty consecutive patients with LMS bifurcation stenosis +/- multivessel disease were treated with SCS technique using paclitaxel-eluting stents. The technique involves simultaneous implantation of two stents (LMS-LAD and LMS-Cx) so that the proximal end of both stents lie at the same level in the body of LMS. Symptom status was recorded and follow-up angiography was performed. In addition, four pigs underwent SCS implantation of the LMS and were studied by direct examination, histology, and scanning electron microscopy. RESULTS: The patients' mean age was 63, 26 were elective and 19 were male. Paclitaxel-eluting stents (Taxus, Boston Scientific) were used. There was one in-hospital death in a highly unstable patient. At 6-month follow-up angiography, two patients required target lesion revascularization. At 13 +/- 3 month follow-up, the remaining patients remain well, with no other major adverse cardiac events. The animals all survived with patent stents. SEM demonstrated full re-endothelialization and histology showed a thin but complete neointima covering the stent struts. CONCLUSION: The SCS technique for treating LMS bifurcation disease with paclitaxel-eluting stents is safe and feasible. Medium term clinical and angiographic results are good. An endothelium and a thin neointima cover the metal struts.

Utility of a whole blood single platelet counting assay to monitor the effects of tirofiban in patients with acute coronary syndromes scheduled for coronary intervention.

This study aimed to establish the utility of a whole-blood single-platelet counting (WBSPC) assay, a measure of microaggregation, in monitoring the effects of tirofiban, comparing this with optical aggregometry (OA) and the Ultegra TRAP cartridge system (UTC), measures of macroaggregation. Fifty-nine patients with acute coronary syndrome scheduled for coronary angiography +/- angioplasty were studied. WBSPC assay (ADP 0.3-100 microM, Sysmex KX21 analyzer), OA (ADP 20 microM) and UTC were performed: before starting tirofiban; 30 min, 4 and 24 h after starting tirofiban; and 1 and 2 h after stopping tirofiban. Thirty minutes after starting tirofiban, there was substantial inhibition of platelet aggregation (40 +/- 30%; WBSPC, 2 minutes after addition of ADP 30 microM) and this remained stable at 4 and 24 h. OA (86 +/- 17%; inhibition of maximal aggregation, ADP 20 microM) and UTC (93 +/- 7%) showed marked inhibition with less inter-individual variation. There was no significant correlation between OA and UTC results (R(2) = 0.006), but fair correlation between OA and WBSPC results (R(2) = 0.37). Greater inhibition of macroaggregation (OA and UTC) was seen compared to microaggregation (WBSPC) such that WBSPC was more discriminating in the therapeutic range when macroaggregation was often completely inhibited. A WBSPC assay of platelet microaggregation shows promise for monitoring GPIIb/IIIa antagonists.