William W. O'Neill

Acute Renal Failure After Coronary Intervention: Incidence, Risk Factors, and Relationship to Mortality

PURPOSE This study set out to define the incidence, predictors, and mortality related to acute renal failure (ARF) and acute renal failure requiring dialysis (ARFD) after coronary intervention. PATIENTS AND METHODS Derivation-validation set methods were used in 1,826 consecutive patients undergoing coronary intervention with evaluation of baseline creatinine clearance (CrCl), diabetic status, contrast exposure, postprocedure creatinine, ARF, ARFD, in-hospital mortality, and long-term survival (derivation set). Multiple logistic regression was used to derive the prior probability of ARFD in a second set of 1,869 consecutive patients (validation set). RESULTS The incidence of ARF and ARFD was 144.6/1,000 and 7.7/1,000 cases respectively. The cutoff dose of contrast below which there was no ARFD was 100 mL. No patient with a CrCl > 47 mL/min developed ARFD. These thresholds were confirmed in the validation set. Multivariate analysis found CrCl [odds ratio (OR) = 0.83, 95% confidence interval (CI) 0.77 to 0.89, P <0.00001], diabetes (OR = 5.47, 95% CI 1.40 to 21.32, P = 0.01), and contrast dose (OR = 1.008, 95% CI 1.002 to 1.013, P = 0.01) to be independent predictors of ARFD. Patients in the validation set who underwent dialysis had a predicted prior probability of ARFD of between 0.07 and 0.73. The in-hospital mortality for those who developed ARFD was 35.7% and the 2-year survival was 18.8%. CONCLUSION The occurrence of ARFD after coronary intervention is rare (<1%) but is associated with high in-hospital mortality and poor long-term survival. Individual patient risk can be estimated from calculated CrCl, diabetic status, and expected contrast dose prior to a proposed coronary intervention.

Impact of sirolimus-eluting stents on outcome in diabetic patients: A SIRIUS (SIRolImUS-coated Bx Velocity balloon-expandable stent in the treatment of patients with de novo coronary artery lesions) substudy☆

Background—Randomized clinical trials have shown that a sirolimus-eluting stent significantly reduces restenosis after percutaneous coronary revascularization. Diabetic patients are known to have a higher risk of restenosis compared with nondiabetic patients. The purpose of this analysis was to determine the impact of sirolimus-eluting stents on outcomes of diabetic compared with nondiabetic patients. Methods and Results—The SIRIUS (SIRolImUS-coated Bx Velocity balloon-expandable stent in the treatment of patients with de novo coronary artery lesions) trial is a randomized, double-blind study that compared sirolimus-eluting and bare metal stent implantation in 1058 patients with de novo native coronary artery lesions. Diabetes mellitus was present in 279 (26%) patients (diabetes mellitus group, 131 patients received sirolimus-eluting stents and 148 patients received bare metal stents) and was absent in 778 patients (no–diabetes mellitus group, 402 patients received sirolimus-eluting stents and 376 patients received bare metal stents). At 270 days, target lesion revascularization was reduced in diabetic patients from 22.3% with bare metal stents to 6.9% with sirolimus-eluting stents (P <0.001) and in nondiabetic patients from 14.1% to 2.99% (P <0.001), respectively. Major adverse cardiac events were reduced in diabetic patients from 25% with bare metal stents to 9.2% with sirolimus-eluting stents (P <0.001) and from 16.5% to 6.5% (P <0.001) in nondiabetic patients, respectively. Conclusions—Implantation of sirolimus-eluting stents compared with bare metal stents in de novo coronary lesions reduces major adverse cardiac events in patients with and without diabetes mellitus. However, among patients receiving sirolimus-eluting stents, there remains a trend toward a higher frequency of repeat intervention in diabetic patients compared with nondiabetic patients, particularly in the insulin-requiring patients.

Argentine Randomized Study: Coronary Angioplasty With Stenting Versus Coronary Bypass Surgery in Patients With Multiple-Vessel Disease (ERACI II): 30-Day and One-Year Follow-up Results

OBJECTIVE The purpose of this study was to compare percutaneous transluminal coronary revascularization (PTCR) employing stent implantation to conventional coronary artery bypass graft surgery (CABG) in symptomatic patients with multivessel coronary artery disease. BACKGROUND Previous randomized studies comparing balloon angioplasty versus CABG have demonstrated equivalent safety results. However, CABG was associated with significantly fewer repeat revascularization procedures. METHODS A total of 2,759 patients with coronary artery disease were screened at seven clinical sites, and 450 patients were randomly assigned to undergo either PTCR (225 patients) or CABG (225 patients). Only patients with multivessel disease and indication for revascularization were enrolled. RESULTS Both groups had similar clinical demographics: unstable angina in 92%; 38% were older than 65 years, and 23% had a history of peripheral vascular disease. During the first 30 days, PTCR patients had lower major adverse events (death, myocardial infarction, repeat revascularization procedures and stroke) compared with CABG patients (3.6% vs. 12.3%, p = 0.002). Death occurred in 0.9% of PTCR patients versus 5.7% in CABG patients, p < 0.013, and Q myocardial infarction (MI) occurred in 0.9% PTCR versus 5.7% of CABG patients, p < 0.013. At follow-up (mean 18.5 +/- 6.4 months), survival was 96.9% in PTCR versus 92.5% in CABG, p < 0.017. Freedom from MI was also better in PTCR compared to CABG patients (97.7% vs. 93.4%, p < 0.017). Requirements for new revascularization procedures were higher in PTCR than in CABG patients (16.8% vs. 4.8%, p < 0.002). CONCLUSIONS In this selected high-risk group of patients with multivessel disease, PTCR with stent implantation showed better survival and freedom from MI than did conventional surgery. Repeat revascularization procedures were higher in the PTCR group.

Intracoronary fibrinolytic therapy in acute myocardial infarction. Report of a prospective randomized trial.

We performed a randomized trial comparing intracoronary administration of streptokinase versus dextrose placebo within six hours after the onset of symptoms of acute myocardial infarction in 40 patients. The base-line clinical, hemodynamic, and angiographic findings were similar in the control and streptokinase-treated groups. Reestablishment of flow occurred in 12 of 20 patients treated with streptokinase and in 2 of 20 given placebo (P less than 0.05). Left ventricular function, angiographic ejection fraction, and regional wall motion, measured before and immediately after intervention, and serial radionuclide ejection fractions, measured at treatment, at 12 days, and at 5 months, were compared according to type of treatment (streptokinase vs. placebo) and outcome of therapy (reperfusion vs. no reperfusion). No statistically significant differences between groups were found. Thus, although streptokinase was more effective than placebo in achieving reperfusion, we detected no improvement of left ventricular function as a result of reestablished coronary flow.

Contemporary outcome trends in the elderly undergoing percutaneous coronary interventions: Results in 7,472 octogenarians

OBJECTIVES We sought to define the risks facing octogenarians undergoing contemporary percutaneous coronary interventions (PCIs). BACKGROUND The procedural risks of PCI for octogenarians have not been well established. METHODS We compared the clinical characteristics and in-hospital outcomes of 7,472 octogenarians (mean age 83 years) with those of 102,236 younger patients (mean age 62 years) who underwent PCI at 22 National Cardiovascular Network (NCN) hospitals from 1994 through 1997. RESULTS Octogenarians had more comorbidities, more extensive coronary disease and a two- to fourfold increased risk of complications, including death (3.8% vs. 1.1%), Qwave myocardial infarction (1.9% vs. 1.3%), stroke (0.58% vs. 0.23%), renal failure (3.2% vs. 1.0%) and vascular complications (6.7% vs. 3.3%) (p < 0.001 for all comparisons). Independent predictors of procedural mortality in octogenarians included shock (odds ratio [OR] 5.4, 95% confidence interval [CI] 3.3 to 8.8), acute myocardial infarction (OR 3.2, 95% CI 2.3 to 4.4), left ventricular ejection fraction (LVEF) <35% (OR 2.9, 95% CI 2.1 to 3.9), renal insufficiency (OR 2.8, 95% CI 2.0 to 3.8), first PCI (OR 2.3, 95% CI 1.7 to 3.3), age >85 years (OR 2.1, 95% CI 1.5 to 2.7) and diabetes mellitus (OR 1.5, 95% CI 1.1 to 2.0). For elective procedures, octogenarian mortality varied nearly 10-fold, and was strongly influenced by comorbidities (0.79% mortality with no risk factors vs. 7.2% with renal insufficiency or LVEF <35%). Despite similar case-mix, PCI outcomes in octogenarians improved significantly over the four years of observation (OR of 0.61 for death/myocardial infarction/stroke in 1997 vs. 1994; 95% CI 0.45 to 0.85). CONCLUSIONS Risks to octogenarians undergoing PCI are two- to fourfold higher than those of younger patients, strongly influenced by comorbidities, and have decreased in the stent era.

Predictors of in-hospital and 6-month outcome after acute myocardial infarction in the reperfusion era: The primary angioplasty in myocardial infarction (PAMI) trial

OBJECTIVES This study examined the predictors of in-hospital and 6-month outcome after different reperfusion strategies in acute myocardial infarction. BACKGROUND Thrombolytic therapy and primary angioplasty are both widely applied as reperfusion modalities in patients with myocardial infarction. Although it is accepted that restoration of early patency of the infarct-related artery can reduce mortality and salvage myocardium, the optimal reperfusion strategy remains controversial, and the predictors of outcome in the reperfusion era have been incompletely characterized. METHODS At 12 centers, 395 patients presenting within 12 h of onset of acute transmural myocardial infarction were prospectively randomized to receive tissue-type plasminogen activator (t-PA) or undergo primary angioplasty without antecedent thrombolysis. Sixteen clinical variables were examined with univariate and multiple logistic regression analysis to identify the predictors of clinical outcome. RESULTS By univariate analysis, in-hospital mortality was increased in the elderly, women, patients with diabetes and in patients treated with t-PA as opposed to angioplasty. Only advanced age and treatment by t-PA versus angioplasty independently correlated with increased in-hospital mortality (6.5% vs. 2.6%, respectively, p = 0.039 by multiple logistic regression analysis). Similarly, the only variables independently related to in-hospital death or nonfatal reinfarction were advanced age and treatment by t-PA versus angioplasty (12.0% vs. 5.1%, p = 0.02). The reduction in in-hospital death or reinfarction with angioplasty versus t-PA was particularly marked in patients > or = 65 years of age (8.6% vs. 20.0%, p = 0.048). Furthermore, primary management with angioplasty versus t-PA was the most powerful multivariate correlate of freedom from recurrent ischemic events (10.3% vs. 28.0%, p = 0.0001). The independent beneficial effect of angioplasty on freedom from death or reinfarction was maintained at 6-month follow-up (8.2% vs. 17.0%, p = 0.02). CONCLUSIONS In the reperfusion era, the two most powerful determinants of freedom from death, reinfarction and recurrent ischemia after myocardial infarction are young age and treatment by primary angioplasty.

Regional Variation across the United States in the Management of Acute Myocardial Infarction

Background Differences in the management of acute myocardial infarction have been reported among countries, but few studies have investigated this issue in regions of the United States. Methods We compared the management of acute myocardial infarction among census regions across the United States, using data from the first Global Utilization of Streptokinase and Tissue Plasminogen Activator for Occluded Coronary Arteries trial (GUSTO-1) comprising 21,772 patients, and from the American Hospital Association. Results We found substantial regional variation in the management of acute myocardial infarction in the United States. Beta-blockers (prescribed for a range of 55 to 81 percent of patients in the various regions), nitrates (prescribed for 61 to 77 percent), and angiotensin-converting–enzyme inhibitors (prescribed for 18 to 23 percent) were used most often in New England, whereas calcium-channel blockers (31 to 42 percent) and lidocaine (14 to 43 percent) were used least often there. Similarly, the prop...

A prospective, randomized evaluation of prophylactic intraaortic balloon counterpulsation in high risk patients with acute myocardial infarction treated with primary angioplasty

OBJECTIVES A large, international, multicenter, prospective, randomized trial was performed to determine the role of prophylactic intraaortic balloon pump (IABP) counterpulsation after primary percutaneous transluminal coronary angioplasty (PTCA) in acute myocardial infarction (AMI). BACKGROUND Previous studies have suggested that routine IABP use after primary PTCA reduces infarct-related artery reocclusion, augments myocardial recovery and improves clinical outcomes. METHODS Cardiac catheterization was performed in 1,100 patients within 12 h of onset of AMI at 34 clinical centers. Clinical and angiographic variables were used to stratify patients undergoing primary PTCA into high and low risk groups. High risk patients were then randomized to 36 to 48 h of IABP (n = 211) or traditional care (n = 226). The study had 80% power to detect a reduction in the primary end point from 30% to 20%. RESULTS There was no significant difference in the predefined primary combined end point of death, reinfarction, infarct-related artery reocclusion, stroke or new-onset heart failure or sustained hypotension in patients treated with an IABP versus those treated conservatively (28.9% vs. 29.2%, p = 0.95). The IABP strategy conferred modest benefits in reduction of recurrent ischemia (13.3% vs. 19.6%, p = 0.08) and subsequent unscheduled repeat catheterization (7.6% vs. 13.3%, p = 0.05) but did not reduce the rate of infarct-related artery reocclusion (6.7% vs. 5.5%, p = 0.64), reinfarction (6.2% vs. 8.0%, p = 0.46) or mortality (4.3% vs. 3.1%) and was associated with a higher incidence of stroke (2.4% vs. 0%, p = 0.03). IABP use did not result in enhanced myocardial recovery as assessed by paired admission to predischarge and 6-week rest and exercise left ventricular ejection fraction. CONCLUSIONS In contrast to previous studies, a prophylactic IABP strategy after primary PTCA in hemodynamically stable high risk patients with AMI does not decrease the rates of infarct-related artery reocclusion or reinfarction, promote myocardial recovery or improve overall clinical outcome.

Lack of Effect of Lovastatin on Restenosis after Coronary Angioplasty

BACKGROUND Experimental and clinical observations suggest that lowering serum lipid levels may reduce the risk of restenosis after coronary angioplasty. We report the results of a prospective, randomized, double-blind trial evaluating whether lowering lipid levels with lovastatin can prevent or delay restenosis after angioplasty. METHODS Seven to 10 days before angioplasty, we randomly assigned eligible patients to receive lovastatin (40 mg orally twice daily) or placebo. Patients who underwent successful, complication-free, first-time angioplasty of a native vessel (the index lesion) continued to receive therapy for six months, when a second coronary angiogram was obtained. The primary end point was the extent of restenosis of the index lesion, as assessed by quantitative coronary arteriography. Of 404 patients randomly assigned to study groups, 384 underwent angioplasty; 354 of the procedures were successful, and 321 patients underwent angiographic restudy at six months. RESULTS At base line, the patients in the lovastatin group (n = 203) and the placebo group (n = 201) were similar with respect to demographic clinical, angiographic, and laboratory characteristics. At base line the mean (+/- SD) degree of stenosis, expressed as a percentage of the diameter of the vessel, was 64 +/- 11 percent in the lovastatin group, as compared with 63 +/- 11 percent in the placebo group (P = 0.22). Despite a 42 percent reduction in the serum level of low-density lipoprotein cholesterol in the lovastatin group, after six months of treatment the amount of stenosis seen in the second angiogram was 46 +/- 20 percent in the placebo group, as compared with 44 +/- 21 percent in the lovastatin group (P = 0.50). Similarly, there were no significant differences in minimal luminal diameter or other measures of restenosis. A trend was noted toward more myocardial infarctions in the lovastatin group, as a result of acute vessel closure or restenosis at the site of angioplasty, but there were no other important differences between the two groups in the frequency of fatal or nonfatal events at six months. CONCLUSIONS Treatment with high-dose lovastatin initiated before coronary angioplasty does not prevent or delay the process of restenosis in the first six months after the procedure.

Percutaneous transluminal coronary angioplasty improves survival in acute myocardial infarction complicated by cardiogenic shock.

Modest survival benefits have been reported in patients with acute myocardial infarction complicated by cardiogenic shock who were treated with early surgical revascularization or thrombolytic therapy. To determine whether coronary angioplasty improves survival, 87 patients with cardiogenic shock complicating acute myocardial infarction at the University of Michigan, Ann Arbor, Michigan, from 1975 to 1985 were retrospectively analyzed. Patients in group 1 (n = 59) were treated with conventional therapy; patients in group 2 (n = 24) were treated with conventional therapy and angioplasty. Extent of coronary artery disease, infarct location, and incidence of multivessel disease were similar between groups. Hemodynamic variables including cardiac index, mean arterial pressure, and pulmonary capillary wedge pressure were also similar. The 30-day survival was significantly improved for group 2 patients (50% vs. 17%, p = 0.006). Survival in group 2 patients with successful angioplasty was 77% (10 of 13 patients) versus 18% (two of 11 patients) in patients with unsuccessful angioplasty, (p = 0.006). The findings suggest that angioplasty improves survival in cardiogenic shock compared with conventional therapy with survival contingent upon successful reperfusion of the infarct-related artery.