Comparative intravascular ultrasound analysis of ostial disease in the left main versus the right coronary artery.

BACKGROUND: Significant aorto-ostial disease is difficult to evaluate with angiography and sometimes even with intravascular ultrasound (IVUS). METHODS: We used IVUS to compare ostial lesions in the left main coronary (LMCA, n = 45) versus the right coronary artery (RCA, n = 50). IVUS measurements were performed each 1 mm beginning within the ostium and continuing to the distal reference segment. Negative remodeling was defined as a remodeling index (lesion/distal reference arterial area) < 0.95. RESULTS: Patient age was 66 +/- 11 years in the LMCA group and 66 +/- 11 years in the RCA group; 56% of the LMCA ostial lesions and 46% of RCA ostial lesions were in males, and 35% of the LMCA ostial lesions and 20% of the RCA ostial lesions were in diabetics. With the exception of a smaller minimum lumen area (p < 0.0001) and distal reference plaque burden (p = 0.002) in ostial RCA lesions and a larger eccentricity index in ostial LMCA lesions (p = 0.001), both sites were remarkably similar. Both ostial LMCA and RCA lesions were short, had modest amounts of calcium, had modest plaque burdens, but had a marked frequency of negative remodeling (84% in LMCA and 86% in RCA; p = 1.0). CONCLUSION: IVUS morphometry is similar in ostial LMCA and RCA lesions; negative remodeling is the dominant contributor to lumen compromise in both locations.

Frequency and severity of plaque prolapse within Cypher and Taxus stents as determined by sequential intravascular ultrasound analysis.

We used intravascular ultrasound to evaluate the incidence, characteristics, and clinical sequel of plaque prolapse within drug-eluting stents. The influence of stent design on plaque prolapse has not been studied. Drug-eluting stents were serially expanded, first at 14 atm and then at 20 atm, with intravascular ultrasound imaging after each inflation. The stent, lumen, and maximum plaque prolapse areas were measured. The residual lumen area and percentage of plaque prolapse burden (maximum plaque prolapse area/stent area) were calculated. Plaque prolapse was divided into grades 1 (<5%), 2 (5% to 10%), and 3 (10% to 20%). Eighty patients (83 lesions, 41 Cypher and 42 Taxus Express stents) were studied. The incidence of plaque prolapse was 41% (17 of 41 lesions) with the Cypher stents versus 24% (10 of 41 lesions) with the Taxus stents after 14 atm (p = 0.096) and 35% (14 of 40) in Cypher stents versus 17.8% (5 of 28) in Taxus stents after 20 atm (p = 0.17). However, the maximum plaque prolapse area was never >20% of the stent area. The frequency and amount of plaque prolapse neither increased nor decreased at higher (20 atm) inflation pressures. Lesions with prolapse were longer (p = 0.004), with a larger external elastic membrane area and greater plaque burden (each p <0.0001) and a larger remodeling index (p = 0.013). Conversely, nonprolapsed plaques had a higher incidence of superficial calcium (p = 0.001). Creatinine kinase-MB elevation was higher with plaque prolapse, and the magnitude of creatinine kinase-MB elevation correlated with the extent of plaque prolapse (r = 0.664, p = 0.002). Multiple logistic regression analysis indicated that a longer lesion length (p = 0.012), and smaller minimal luminal area (p = 0.031) had higher risks of plaque prolapse. In conclusion, plaque prolapse was frequently observed in Cypher and Taxus stents. However, sequential intravascular ultrasound imaging showed that the frequency and amount of plaque prolapse were neither increased nor decreased by additional higher pressure inflations.

Percutaneous coronary intervention with drug-eluting stents in octogenarians: characteristics, clinical presentation, and outcomes.

OBJECTIVES: We aimed to compare clinical outcomes of octogenarians > or =80 years of age after coronary drug-eluting stent (DES) implantation. BACKGROUND: Although octogenarians constitute a fast-growing portion of cardiovascular patients, they are not adequately represented in current clinical revascularization trials. METHODS: We analyzed the data of 3,166 consecutive patients who underwent percutaneous coronary intervention (PCI) and DES implantation since March 2003. Periprocedural events, 1- and 6-month clinical outcomes were compared between octogenarians (n = 339) and patients <80 years of age (n = 2,827). RESULTS: Baseline characteristics revealed a higher prevalence of females (P < 0.001), Caucasians (P = 0.004), chronic renal failure (P < 0.001), heart failure (P < 0.001), number of diseased vessels (P = 0.009), and lower ejection fraction (P = 0.03) in octogenarians. Patients <80 years showed more positive family history (P < 0.001), hyperlipidemia (P = 0.006), smoking (P < 0.001), and obesity (P < 0.001). Clinical presentation and procedural success were similar in both groups as were death, myocardial infarction (MI), and repeat revascularization in-hospital. At 6 months, restenosis rates were low and comparable. In the subgroup of octogenarians who presented with acute coronary syndrome, mortality (15% vs. 3%, P < 0.001) and Q-wave MI occurred more often. Multivariate analysis revealed age >80 (P = 0.008), cardiogenic shock (P < 0.001), Q-wave MI at presentation (P = 0.003), and length of hospital stay (P = 0.003) to be independent predictors of mortality. CONCLUSIONS: PCI with DES in octogenarians results in a similar reduction of restenosis rates when compared to patients <80 years. Yet in octogenarians who presented with acute coronary syndrome, incidence of mortality and Q-wave MI at 6 months was higher as compared to younger patients.

Negative remodeling and calcified plaque in octogenarians with acute myocardial infarction: an intravascular ultrasound analysis.

OBJECTIVES: The goal of this study was to use intravascular ultrasound (IVUS) to compare octogenarians versus patients <65 years of age with regard to culprit lesion morphology in acute myocardial infarction (MI). BACKGROUND: Although octogenarians represent the fastest-growing segment of our population and have a higher risk profile, they are underrepresented in therapeutic trials. METHODS: Between 2002 and 2005, 42 octogenarians and 52 patients <65 years of age underwent pre-intervention IVUS within 2 days from onset of an MI. Qualitative and quantitative measurements were performed at the lesion site and at the proximal and distal references. Positive remodeling was defined as a remodeling index (lesion/mean reference arterial area) > or =1. RESULTS: Elderly patients mostly (71%) presented with non-ST-segment elevation myocardial infarction (NSTEMI), whereas patients <65 years of age presented almost equally with ST-segment elevation myocardial infarction (STEMI) and NSTEMI (56% vs. 44%). The frequency of rupture/dissection was greater in the <65-year-old group (32% vs. 9%, p = 0.009), and culprit lesions contained more thrombus in this group (14% vs. 2%, p = 0.04). Conversely, in octogenarians, lesions were predominantly calcified (57% vs. 10%, p < 0.001) and longer (20.9 +/- 7.8 mm vs. 16.6 +/- 6.1 mm, p = 0.004) with less positive remodeling (19% vs. 56%, p < 0.001). On multivariant logistic regression analysis, age was the only independent predictor of calcified plaque (p = 0.02) and remodeling (p = 0.005). CONCLUSIONS: Negative remodeling and calcified plaque with rare plaque ruptured were common in elderly people with acute MI. These findings may contribute to the difference in clinical presentation and may suggest a different pathophysiologic mechanism of MI in octogenarians.

Clinical outcomes after percutaneous coronary intervention with drug-eluting stents in dialysis patients.

OBJECTIVES: We aimed to compare the clinical outcomes of dialysis versus nondialysis patients after coronary drug-eluting stent (DES) implantation. BACKGROUND: The revascularization of ischemic heart disease in dialysis patients has remained controversial due to consistent exclusion of this population from major trials, especially in the context of percutaneous coronary interventions (PCI) with DES. METHODS: We analyzed the data on 3,442 consecutive patients who underwent PCI and DES implantation since March 2003. Periprocedural events, 1- and 6-month clinical outcomes were then compared between dialysis (n = 72) and nondialysis patients (n = 3,370). RESULTS: Baseline characteristics revealed a higher prevalence of female gender (p = 0.03), African Americans (p < 0.001), hypertension (p < 0.001), diabetes mellitus (p < 0.001), number of diseased vessels (p = 0.04), lower ejection fraction (p < 0.001), and a higher prevalence of acute myocardial infarction (MI) (p = 0.04) in dialysis patients. Nondialysis patients showed more history of smoking (p < 0.001) and obesity (p = 0.02). Procedural success was higher (p = 0.05), while there was a trend toward a lower mortality rate, in the nondialysis group during hospitalization. At 6 months, the restenosis rate was low and comparable, but mortality occurred more often (16% vs. 3.8%; p < 0.001) in dialysis patients. Multivariate analysis revealed cardiogenic shock (p = 0.04) to be an independent predictor of mortality. CONCLUSIONS: PCI with DES in dialysis patients is safe and feasible, with a similar reduction of repeat revascularization when compared with nondialysis patients. There was, however, a higher incidence of mortality in dialysis patients at 6 months, mostly influenced by contributing comorbidities and more severe conditions at presentation.

An intravascular ultrasound analysis of the mechanisms of restenosis comparing drug-eluting stents with brachytherapy.

There are treatment failures after de novo drug-eluting stent (DES) implantation and after treatment with DESs or vascular brachytherapy (VBT) of in-stent restenosis (ISR) lesions. We studied 38 patients who presented with DES failure (26 patients after de novo DES implantation and 12 patients after DES treatment of ISR) and 30 patients who presented with VBT failure (all after treatment of ISR). Standard clinical data were collected and volumetric intravascular ultrasound was measured. Patients who presented with DES failures were 58.8 +/- 9.6 years of age and those who presented with VBT failures were 59.8 +/- 8.7 years of age; 60.5% of DES and 58.6% of VBT failures were in men; 31.5% of DES failures and 46.6% of VBT failures occurred in diabetic patients; and times to presentation were 210 +/- 101 days in DES failures and 510 +/- 527 days in VBT failures (p = 0.001). Minimal stent area was significantly larger in VBT than in the 2 DES failure groups (de novo DES implantation and DES treatment of ISR, p <0.0001); this was associated with more neointimal hyperplasia in VBT failures (p <0.0001). After it was normalized to stent length, intimal hyperplasia was diffusely distributed in VBT failures; conversely, DES failures were associated with less intimal hyperplasia and the intimal hyperplasia was mostly focal, with greater accumulation in the proximal and mid segments. In conclusion, VBT failures were caused by significant, recurrent, and diffuse intimal hyperplasia in the setting of adequate stent expansion, whereas DES failures were caused by only modest, but focal, intimal hyperplasia in the setting of DES underexpansion.

Clopidogrel loading dose (300 versus 600 mg) strategies for patients with stable angina pectoris subjected to percutaneous coronary intervention.

We evaluated the effect of high versus low loading doses of clopidogrel in patients with stable angina pectoris who underwent percutaneous coronary intervention (PCI) on periprocedural events, in-hospital complications, and 30-day outcomes. The recommended loading dose of clopidogrel for patients with PCI is currently 300 mg. Recent studies have suggested that 600 mg may decrease periprocedural complications in patients with unstable angina. However, whether this holds for patients with stable angina pectoris is unknown. We reviewed records of 445 patients with stable angina pectoris who underwent PCI and were loaded with 300 mg (n = 126) or 600 mg (n = 319) of clopidogrel immediately before the procedure. Study end points were periprocedural ischemic events, bleeding complications, and a composite of major adverse cardiac events at 30 days. Baseline characteristics and procedural indexes were similar between groups. Major in-hospital complications were recorded in 2 patients in the 600-mg group and in no patient in the 300-mg group (p = 1.00). Postprocedural increase of cardiac enzymes (troponin I, p = 0.91; creatinine kinase-MB, p = 0.395) and major bleeding (0.6% vs 0%, p = 1.00) were comparable, as was 30-day major adverse cardiac events (1.2% vs 0%, p = 0.56). Multivariate analysis did not identify any risk decrease for periprocedural myocardial infarction with 600 mg of clopidogrel (odds ratio 2.68, 95% confidence interval 0.74 to 9.78, p = 0.135). In conclusion, in patients with stable angina pectoris, a 300-mg clopidogrel loading dose, when given immediately before PCI, is sufficient. Although 600 mg was clinically safe, it was not associated with fewer periprocedural events and improved 30-day outcomes compared with 300 mg.