Objectives The study objective was to determine the impact of diabetes on radial artery and saphenous vein graft occlusion and clinical outcomes more than 5 years after coronary artery bypass surgery ...in the multicenter Radial Artery Patency Study (NCT00187356). Methods A total of 529 patients aged less than 80 years with triple-vessel disease undergoing coronary bypass surgery participated in this study. Angiographic follow-up occurred more than 5 years after surgery with annual clinical follow-up. The primary objective was to compare the proportion of complete graft occlusion between radial artery and saphenous vein grafts among diabetic and nondiabetic persons. Additional objectives included determining predictors of complete graft occlusion and comparison of major adverse cardiac events defined by cardiac death, late myocardial infarction, and reintervention. Results There were 148 of 529 patients (27.8%) with diabetes; 269 patients (83/269 30.9% diabetic) underwent late angiography at mean of 7.7 ± 1.5 years after surgery. In diabetic patients, the proportion of complete graft occlusion was significantly lower in the radial grafts (4/83 4.8%) than in the saphenous grafts (21/83 25.3%) ( P = .0004), and this was similar in nondiabetic patients ( P = .19). Multivariate modeling showed that the use of the radial artery and high-grade target vessel stenosis were protective against late graft occlusion, whereas female gender, smoking history, and elevated creatinine were associated with an increased risk; interaction between diabetic status and conduit type also was significant ( P = .02). Major adverse cardiac events were higher in diabetic patients (23/148 15.5% vs 35/381 9.2%, P = .04). Conclusions The use of the radial artery should be strongly considered in diabetic patients undergoing coronary bypass surgery, especially with high-grade target vessel stenosis.
Background Graft stenosis may be associated with future graft failure. The purpose of this investigation was to compare graft stenosis between radial artery (RA) grafts and saphenous vein grafts ...(SVGs) at least 5 years postoperatively using the multicenter Radial Artery Patency Study (RAPS) data. Methods Two hundred thirty-four patients underwent late invasive angiography after coronary artery bypass operations. The study population consists of 163 patients with thrombolysis in myocardial infarction (TIMI) 3 flow of both the RA graft and study SVGs. Angiograms were reviewed centrally and in a blinded fashion. Graft stenosis was recorded for the proximal anastomosis, graft body, and distal anastomosis; significant stenosis was defined as greater than or equal to 50%. Major adverse cardiac events (MACE) were reported in patients with and those without significant graft stenosis. Results There was no difference in significant graft stenosis of the patent RA grafts and SVGs (14 of 163 8.6% versus 19 of 163 11.7%) or in the proximal anastomosis (5 of 163 3.1% versus 5 of 163 3.1%), graft body (6 of 163 3.7% versus 13 of 163 8.0%), or distal anastomosis (4 of 163 2.5% versus 5 of 163 3.1%) considered separately. However, the overall burden of graft body disease was higher in SVGs ( p = 0.03). MACE was higher in patients with significant graft stenosis than in patients without stenosis (10 of 28 35.7% versus 7 of 135 5.2%; p < 0.0001). Conclusions There was no significant difference in the rates of significant stenosis of patent RA grafts and SVGs more than 5 years postoperatively. However, the burden of graft body stenosis was less in RA grafts compared with SVGs, suggesting that the RA grafts will continue to outperform the SVGs late after operation.
Objectives To identify novel predictors for coronary artery bypass grafting failure, we probed for associations with known clinical and biochemical risk factors for atherosclerosis. We also used ...microarray analysis to identify novel single nucleotide polymorphisms to better understand the genetics and pathogenesis of graft occlusion. Methods The present study was a nested case-control substudy of the Radial Artery Patency Study 5-year follow-up data. From 1996 to 2001, 87 patients underwent coronary artery bypass grafting. Of these, 26 patients (29.9%) had an occluded study graft (saphenous vein or radial artery) at 8.0 ± 1.1 years. The clinical parameters, late angiography, blood biomarker levels, and surgical outcomes data were included in a multivariate analysis to determine the independent predictors of graft failure. Results The risk factors of graft failure were fibrinogen (odds ratio OR, 3.94; 95% confidence interval CI, 1.33-11.63; P = .01), creatinine (OR, 1.06; 95% CI, 1.02-1.10; P = .006), and diabetes mellitus (OR, 5.15; 95% CI, 1.08-24.59; P = .04). High-density lipoprotein (OR, 0.74; 95% CI, 0.53-1.02; P = .06) was weakly protective; however, low-density lipoprotein and total cholesterol were not predictors. We then identified the association of several human single nucleotide polymorphisms with graft failure, including mutations in glutathione-S-transferase α3 . Human coronary arteries and bypass grafts demonstrated increased protein expression of glutathione-S-transferase α3, a known cardioprotective factor, in the atherosclerotic regions and surrounding adventitial tissues. Conclusions We identified diabetes as a potential clinical predictor and plasma fibrinogen, creatinine, and high-density lipoprotein as potential novel biomarkers. These might help risk stratify patients for the development of graft failure. We also demonstrated a novel association between glutathione-S-transferase α3 and graft failure.
Background Studies evaluating the efficacy and safety of the transradial approach for percutaneous coronary intervention (PCI) were carried out mainly before the widespread use of stents and ...glycoprotein (GP) IIb/IIIa inhibitors. We sought to determine the association between the choice of the vascular access site and procedural complications after PCI performed with routine stenting and GP IIb/IIIa inhibition. Methods The data source was a prospective registry of 13,499 consecutive cases of PCI at the University Health Network, Toronto, Canada, from April 2000 to September 2006. Logistic regression was used to calculate the probability of selection to the radial access group. Using propensity score methodology, 3,198 patients with femoral access were randomly matched to 3,198 patients with radial access based on clinical, angiographic, and procedural characteristics. Multivariable logistic regression analysis was used to identify the independent predictors of access site–related complications. Major adverse cardiac event was defined as death, myocardial infarction, abrupt vessel closure, or coronary artery bypass surgery. Results Use of the transradial approach was associated with fewer vascular access complications (1.5% vs 0.6%, P < .001) and a shorter length of hospital stay. Multivariable analysis revealed transradial access (OR 0.39, 95% CI 0.2-0.7) to be an independent predictor of lower risk, whereas primary PCI (OR 4.36, 95% CI 1.4, 13), recent myocardial infarction (OR 2.0 95% CI 1.2, 3.4), age (per 10 years increase: OR 1.37, 95% CI 1.1-1.7) and female gender (0R 2.78 95% CI 1.7, 4.6) were independent predictors of a higher risk of access site complications. Conclusions Use of transradial access for PCI is safe and is independently associated with a reduced rate of in-hospital access site complications and reduced length of hospital stay.
Abstract Background Myocardial contrast echocardiography during angiography is critical in identifying appropriate septal perforator(s) for alcohol septal ablation (ASA) in patients with hypertrophic ...obstructive cardiomyopathy. We evaluated whether there were other angiographic and/or echocardiographic markers that might identify patients who are anatomically suitable for ASA. Methods We performed quantitative coronary angiographic analysis and echocardiographic assessment on 74 patients referred for ASA from January 2004 to July 2012 at the Peter Munk Cardiac Centre, University Health Network, Toronto, Ontario, Canada. Patients who proceeded to ASA were compared with those in whom ASA was aborted. Results Of the 74 patients referred for ASA, 63 proceeded to ASA and in 11 patients ASA was aborted because of various anatomic and technical reasons. There were no clinically significant differences observed in quantitative angiographic and echocardiographic measurements between the 2 groups. The ratio of ostial left main (LM) to ablated septal distance on angiography vs the basal septum to the septum area where the mitral valve contacted the septum because of systolic anterior motion (SAM) was 1.53. In the whole cohort, a significant correlation was observed between the ostial LM to the target septal distance and the distance from basal septum to SAM-septal contact point on echocardiography ( r = 0.39; P = 0.008). A stronger correlation was evident when analysis was restricted to patients undergoing ASA only ( r = 0.44; P = 0.006). Conclusions Echocardiographic and angiographic assessments of the distance between the basal septum to SAM-septal contact point and ostial LM to the target septal distance might be useful in preprocedural selection of the appropriate septal perforator for ASA.
Patients with chronic renal insufficiency (RI) have higher in-hospital mortality and major adverse cardiac event (MACE) rates after percutaneous coronary intervention (PCI). The mechanisms of this ...adverse course are not well understood. It was hypothesized that this worse outcome may be caused by inadequate PCI results secondary to more complex coronary anatomy in patients with RI. Baseline, procedural, and outcome variables of all PCI cases at the University Health Network are entered prospectively in the PCI Registry. All PCI cases between April 1, 2000, and October 31, 2005, excluding patients in shock, who had preprocedural creatinine clearance (CrCl) measured were included in this study (n = 10,821 of 11,023 patients). Moderate RI (CrCl <60 ml/min) was evaluated as an independent predictor of procedural outcomes, death, and MACE (defined as death, myocardial infarction, abrupt closure, or coronary artery bypass grafting). Moderate RI (CrCl <60 ml/min) independently predicted the procedural outcomes of worse residual stenosis >20% (p = 0.03), number of undeliverable stents (p = 0.003), and smallest stent diameter (p <0.001). Worst residual stenosis >20% and any undeliverable stent were significantly associated with in-hospital MACEs (odds ratio OR 3.97, 95% confidence interval CI 3.0 to 5.3, p <0.001 and OR 1.89, 95% CI 1.2 to 2.9, p = 0.002) and mortality (OR 3.82, 95% CI 2.2 to 6.7, p <0.001 and OR 3.0, 95% CI 1.6 to 5.9, p = 0.002). These risks were independent of all other measured variables. In conclusion, moderate to severe RI was a strong predictor of worse procedural results during PCI, which, in turn, were independent predictors of in-hospital MACE and mortality and independent contributors to the higher risk of in-hospital adverse events observed after PCI in patients with RI.
The optimal approach to percutaneous coronary intervention (PCI) of bifurcation lesions remains unclear, reflecting lack of long-term follow-up and heterogeneity of lesions encountered. We evaluated ...the long-term outcome of patients undergoing bifurcation PCI followed in the prospective bifurcation registry at the University Health Network, Toronto, Ontario, Canada. Of 526 patients undergoing bifurcation PCI between November 2003 and March 2005, most (n = 406) were treated by main vessel stenting only (n = 266) or crush/culotte stenting (n = 140). After median follow-up of 26.5 months, major adverse cardiac events (MACEs) and Canadian Cardiovascular Society class ≥2 angina occurred in 28.5% and 22.3% of patients in these groups, respectively (p = 0.190), whereas MACE rates were 20.8% for main vessel stenting and 18.7% for crush/culotte stenting (p = 0.670). A low bifurcation angle was associated with better outcomes in the crush/culotte group but had no effect on outcome of patients treated with main vessel stenting only. Use of crush/culotte techniques independently predicted freedom from MACEs or Canadian Cardiovascular Society class ≥2 angina compared with main vessel stenting only (odds ratio 0.55, 95% confidence interval 0.32 to 0.94, p = 0.029). In conclusion, the use of crush/culotte stenting is safe, with efficacy and MACE rates being similar to main vessel stenting alone. Our observations regarding the effect of lesion characteristics such as bifurcation angle and extent of side branch disease on outcome underscore the need for randomized trials that are inclusive of patients with complex side branch disease.
Previous studies have reported differences in presenting symptoms and angiographic characteristics between women and men undergoing evaluation for suspected coronary artery disease (CAD). We examined ...the relation between symptoms and extent of CAD in patients with type 2 diabetes mellitus and known CAD enrolled in the Bypass Angioplasty Revascularization Investigation 2 Diabetes (BARI 2D) trial. Of 1,775 patients (533 women, 30%, and 1,242 men, 70%), women were more likely than men to have angina (65% vs 56%, p <0.001) or an atypical angina/anginal equivalent (71% vs 58%, p <0.001). More women reported unstable angina (17% vs 13%, p = 0.047) or were in a higher Canadian Cardiology Society class compared to men (Canadian Cardiology Society classes II to IV 78% vs 68%, p = 0.002). Fewer women than men had no symptoms (14% vs 22%, p <0.001). Women had a lower mean myocardial jeopardy index (42.5 ± 24.3 vs 47.9 ± 24.3, p <0.001), smaller number of total significant lesions (2.3 ± 1.7 vs 2.7 ± 1.8, p <0.001), and fewer jeopardized left ventricular regions (p <0.001 for distribution) or long-term occlusions (29% vs 42%, p <0.001). After adjustment for relevant covariates, the odds of having CAD symptoms were still higher in women than men (odds ratio for angina 1.31, 95% confidence interval 1.02 to 1.69; odds ratio for atypical angina 1.52, 95% confidence interval 1.17 to 1.96). In conclusion, in a high-risk group of patients with known CAD and diabetes mellitus, women were more symptomatic than men but had less obstructive CAD. These data suggest that factors other than epicardial CAD severity influence symptom presentation in women in this population.
Objectives The purpose of the study is to identify the predictors of clinical outcome (mortality and survival without repeat septal reduction procedures) of alcohol septal ablation for the treatment ...of patients with hypertrophic obstructive cardiomyopathy. Background Alcohol septal ablation is used for treatment of medically refractory hypertrophic obstructive cardiomyopathy patients with severe outflow tract obstruction. The existing literature is limited to single-center results, and predictors of clinical outcome after ablation have not been determined. Registry results can add important data. Methods Hypertrophic obstructive cardiomyopathy patients (N = 874) who underwent alcohol septal ablation were enrolled. The majority (64%) had severe obstruction at rest, and the remaining had provocable obstruction. Before ablation, patients had severe dyspnea (New York Heart Association NYHA functional class III or IV: 78%) and/or severe angina (Canadian Cardiovascular Society angina class III or IV: 43%). Results Significant improvement (p < 0.01) occurred after ablation (∼5% in NYHA functional classes III and IV, and 8 patients in Canadian Cardiovascular Society angina class III). There were 81 deaths, and survival estimates at 1, 5, and 9 years were 97%, 86%, and 74%, respectively. Left anterior descending artery dissections occurred in 8 patients and arrhythmias in 133 patients. A lower ejection fraction at baseline, a smaller number of septal arteries injected with ethanol, a larger number of ablation procedures per patient, a higher septal thickness post-ablation, and the use beta-blockers post-ablation predicted mortality. Conclusions Variables that predict mortality after ablation, include baseline ejection fraction and NYHA functional class, the number of septal arteries injected with ethanol, post-ablation septal thickness, beta-blocker use, and the number of ablation procedures.