Faculty Bibliography

OBJECTIVES: To address the safety and efficacy of drug-eluting stents (DES) in the treatment of intermediate lesions, we performed a pooled analysis of four randomized DES versus bare-metal stent (BMS) trials and assessed outcomes among patients with intermediate lesions. BACKGROUND: Before the introduction of DES, intermediate coronary lesions were commonly managed based on physiologic or anatomic assessment of lesion severity. The DES may challenge this paradigm. METHODS: The study population involved 167 of 2,478 randomized patients (6.7%) with intermediate lesions (diameter stenosis <50% [mean 44%] by quantitative coronary angiography) from the Sirolimus-coated Bx Velocity Balloon Expandable Stent in the Treatment of Patients with De Novo Coronary Artery Lesions (SIRIUS), TAXUS-IV, and the First and Second First Use to Underscore Restenosis Reduction with Everolimus (FUTURE-I and -II) trials. End points examined included early (in-hospital and 30-day) and late (1-year) major adverse cardiac events (MACE), including cardiac death, myocardial infarction (MI), target vessel revascularization (TVR), stent thrombosis, and follow-up angiographic restenosis. RESULTS: Patients with intermediate lesions randomized to DES versus BMS had low rates of 30-day MACE (1.1% vs. 4.0% respectively; p = 0.22). At one-year follow-up, patients treated with DES versus BMS had similar rates of cardiac death (0% vs. 2.7%, respectively; p = 0.11) and MI (3.4% vs. 5.4%; p = 0.49) but markedly lower rates of TVR (3.4% vs. 20.3%; p = 0.0004), MACE (5.6% vs. 25.4%; p = 0.0003), and binary angiographic restenosis (1.8% vs. 34.0%; p < 0.0001). No patient in either group developed stent thrombosis. CONCLUSIONS: Compared with BMS, treatment of intermediate lesions with DES appears safe and results in a marked reduction in clinical and angiographic restenosis. The efficacy of DES may require a reevaluation of current treatment paradigms for intermediate lesions

Previous studies have reported differences in interventional complication rates that depend on saphenous vein graft (SVG) lesion location. However, little is known about morphologic differences between lesions in different SVG locations. We evaluated preintervention intravascular ultrasound (IVUS) images of 75 de novo SVG lesions (aorto-ostial, n = 15; shaft, n = 60) in 63 patients. IVUS data were measured at the minimal lumen area and at 2 proximal and 2 distal references. Positive remodeling was defined as a lesion site SVG area that was larger than the average of the 2 distal references. Shaft lesions more often contained soft plaque (60.0% vs 26.7%, p = 0.02). Minimal lumen areas were identical (4.5 +/- 2.9 vs 4.3 +/- 1.5 mm2, p = 0.3); however, plaque burden at the minimal lumen area was greater in shaft locations (79.3 +/- 9.4% vs 72.1 +/- 9.2%, p = 0.01). The frequency of positive remodeling in shaft versus aorto-ostial lesions was 70.2% versus 26.7% (p = 0.002). SVG shaft lesions have more soft plaque and larger plaque burdens and undergo positive remodeling more frequently than SVG aorto-ostial lesions. These IVUS differences may account for some of the location-specific differences in interventional complications

BACKGROUND: Although intravascular ultrasound (IVUS) can detect plaque rupture, the fibrous cap remnant has not previously been studied in detail. The aim of the present study is to assess the fibrous cap remnants by IVUS in ruptured plaques. METHODS: In 53 patients, a ruptured plaque with a fibrous cap remnant was studied by IVUS. RESULTS: In 36 (68%) patients, the rupture of the fibrous cap appeared to have occurred at the shoulder. The absolute length of the fibrous cap remnant was significantly longer in the center rupture site compared with the shoulder rupture site (1.37 +/- 0.56 vs 0.84 +/- 0.34 mm, P = .001); however, the estimated length of the original fibrous cap did not differ between the 2 rupture site groups (2.28 +/- 0.66 vs 2.11 +/- 0.69, P = not significant). In none of the patients did the remnants of the fibrous cap cover the entire mouth of the cavity. The estimated absolute length of the missing part of the fibrous cap correlated significantly with the cavity area (r = 0.517, P < .001), the lesion external elastic membrane area (r = 0.330, P = .016), the lumen area (r = 0.289, P = .036), the maximum plaque thickness (r = 0.364, P = .007), and the length of the estimated original fibrous cap (r = 0.709, P < .001). CONCLUSION: In general, the postrupture fibrous cap does not cover the entire mouth of the ruptured plaque cavity in its postrupture state. Potential explanations include the following: (1) part of the fibrous cap may be too thin to be visualized with IVUS, (2) part of it may have embolized, or (3) the prerupture fibrous cap may have been stretched and/or there were postrupture changes in lesion geometry

The neointimal hyperplasia (IH) distribution pattern of in-stent restenotic lesions after sirolimus-eluting stent (SES) implantation has not been well described. We identified 48 in-stent restenotic lesions (41 patients) after SES implantation and performed volumetric intravascular ultrasound analyses. Lumen area, stent area, and IH area at the minimal lumen area site were 2.7 +/- 1.0, 5.4 +/- 1.9, and 2.7 +/- 1.4 mm(2), respectively. IH area at the minimal lumen site was larger in the group with a stent area > or =5.0 mm(2) than the group with a stent area <5.0 mm(2) (3.7 +/- 1.3 vs 1.9 +/- 0.8 mm(2), p <0.001). There were fewer visualized stent struts in lesions with a minimum stent area > or =5.0 mm(2) at the minimum lumen site compared with those with a stent area <5.0 mm(2) (0.69 +/- 0.25 vs 0.83 +/- 0.16, p = 0.04). When we compared lesions in patients with diabetes mellitus with patients without diabetes, minimum lumen areas, percent IH at minimal lumen area, percent IH, and neointima-free stent length were identical. In conclusion, (1) lesions without SES underexpansion at the minimum lumen site had more IH and greater nonuniform stent strut distribution compared with restenotic SESs that were underexpanded, and (2) the IH response did not appear to be more aggressive in patients with diabetes mellitus than in those without diabetes mellitus

We investigated the fate of postprocedural incomplete stent apposition (ISA) after sirolimus-eluting stent (SES) implantation by evaluating long-term intravascular ultrasound findings in 168 consecutive patients (182 de novo lesions). Postprocedural ISA was defined as > or = 1 stent strut that was clearly separated from the vessel wall with evidence of blood speckle behind the strut without overlapping a side branch. After SES implantation, there were 61 ISA sites in 46 stents in 31 patients (23 at the proximal edge, 7 at the distal edge, and 31 within the stent body). There were no clinical, procedural, or intravascular ultrasound measurement differences between patients and lesions with versus without ISA. At follow-up, 15 acute ISA sites (25%) in 11 patients completely resolved and 40 sites (75%) in 20 patients persisted, although 32 of 46 persisting ISA sites (70%) decreased. There was a greater decrease in effective lumen area and a greater increase in peristent plaque area in the complete-resolution group than in the persistent-ISA group. No lesion developed stent thrombosis or in-stent restenosis (angiographic diameter stenosis > 50%). Six acute ISA sites were also associated with new, late acquired ISA, only 1 of which resulted in aneurysm formation. Although most ISAs after SES implantation do not resolve completely, the incidence of restenosis or thrombosis is not affected

We previously found that contrast-induced nephropathy (CIN) complicating percutaneous coronary intervention adversely affects patients with chronic kidney disease (CKD). Therefore, we further investigated whether the predictors and outcome of CIN after percutaneous coronary intervention differ among patients with versus without CKD. Among 7,230 consecutive patients, CIN (>or=25% or >or=0.5 mg/dl increase in preprocedure serum creatinine 48 hours after the procedure) developed in 381 of 1,980 patients (19.2%) with baseline CKD (estimated glomerular filtration rate [eGFR] <60 ml/min/1.73 m(2)) and in 688 of 5,250 patients (13.1%) without CKD. Decreased eGFRs, periprocedural hypotension, higher contrast media volumes, lower baseline hematocrit, diabetes, pulmonary edema at presentation, intra-aortic balloon pump use, and ejection fraction <40% were the most significant predictors of CIN in patients with CKD. Apart from intra-aortic balloon pump use, predictors of CIN in patients without CKD were the same as mentioned, plus older age and type of contrast media. Regardless of baseline renal function, CIN correlated with longer in-hospital stay and higher rates of in-hospital complications and 1-year mortality compared with patients without CIN. By multivariate analysis, CIN was 1 of the most powerful predictors of 1-year mortality in patients with preexisting CKD (odds ratio 2.37, 95% confidence interval 1.63 to 3.44) or preserved eGFR (odds ratio 1.78; 95% confidence interval 1.22 to 2.60). Thus, regardless of the presence of CKD, baseline characteristics and periprocedural hemodynamic parameters predict CIN, and this complication is associated with worse in-hospital and 1-year outcomes

Intravascular ultrasound (IVUS) evaluation was performed in 33 lesions with sirolimus-eluting stent (SES) failure: 4 thromboses, 26 in-stent restenoses (including 6 edge stenoses), 4 new stenoses >5 mm proximal to the stent, and 1 patient with no evidence of the implanted SES (presumably because of embolization). A minimum stent area <5.0 mm(2) (stent underexpansion) was observed in 67% of all SES failures (in particular, 67% of intrastent restenosis); negative remodeling was observed in 4 of 6 stent edge restenoses, and new lesions were secondary to an increase in plaque area

BACKGROUND: The relationship between low hematocrit and contrast-induced nephropathy has not been investigated. METHODS: Of 6,773 consecutive patients treated with percutaneous coronary intervention, contrast-induced nephropathy (an increase of >/=25% or >/=0.5 mg/dL in preprocedure serum creatinine, at 48 hours postprocedure) occurred in 942 (13.9%) patients. RESULTS: Rates of contrast-induced nephropathy steadily increased as baseline hematocrit quintile decreased (from 10.3% in the highest quintile to 23.3% in the lowest quintile) (chi(2) for trend, P < 0.0001). Stratification by baseline estimated glomerular filtration rate (eGFR) and baseline hematocrit showed that the rates of contrast-induced nephropathy were the highest (28.8%) in patients who had the lowest level for both baseline eGFR and hematocrit. Patients with the lowest eGFR but relatively high baseline hematocrit values had remarkably lower rates of contrast-induced nephropathy (15.8%, 12.3%, 17.1%, and 15.4% in 2nd, 3rd, 4th, and 5th quintiles of baseline hematocrit, respectively) (P < 0.0001). The rates of contrast-induced nephropathy increased with increment in change in hematocrit. Patients in the lowest quintile of baseline hematocrit with absolute hematocrit drop >5.9% had almost doubled rates of contrast-induced nephropathy compared with patients with hematocrit change <3.4% (38.1% vs. 18.8%, respectively) (P < 0.0001). By multivariate analysis, lower baseline hematocrit was an independent predictor of contrast-induced nephropathy; each 3% decrease in baseline hematocrit resulted in a significant increase in the odds of contrast-induced nephropathy in patients with and without chronic kidney disease (11% and 23%, respectively). When introduced into the multivariate model instead of baseline hematocrit, change in hematocrit also showed a significant association with contrast-induced nephropathy. CONCLUSION: Lower hematocrit is an important risk factor for contrast-induced nephropathy. Whether correcting the hematocrit prepercutaneous coronary intervention might decrease the rates of contrast-induced nephropathy should be addressed in a prospectively designed trial

Patients with acute coronary syndrome are at increased risk of acute and long-term events after stent implantation. We compared the impact of intravascular ultrasound detected plaque rupture on creatine kinase-MB (CK-MB) isoenzyme release and clinical outcomes by comparing 62 patients with ruptured plaques with 62 matched control patients who underwent stent implantation. Two thirds of the patients in each group presented with an acute coronary syndrome. There were no differences in procedural complications between groups, although patients with ruptured plaque had higher CK-MB elevation rates than those without ruptured plaque (1 to 3 times the upper limit of normal CK-MB, 35% vs 10%, p <0.001; >3 times the upper limit, 15% vs 2%, p = 0.02). Independent predictors of CK-MB elevation were presence of ruptured plaque (p = 0.03) and unstable angina (p = 0.04). Patients with ruptured plaque had higher composite rates of late events (target lesion revascularizations/myocardial infarctions/cardiac deaths) than controls (25% vs 9%, p = 0.03). These results were similar when only patients with acute coronary syndrome were studied. Plaque rupture morphology is associated with higher periprocedural CK-MB release and worse 1-year clinical outcome in patients treated with coronary stenting

The purpose of this study was to report the angiographic findings of the first human evaluation of the everolimus-eluting stent (EES) for the treatment of noncomplex coronary lesions. Forty-two patients with de novo coronary lesions (2.75 to 4.00 mm vessels; lesion length, <18 mm) were prospectively randomized in a 2:1 ratio to receive either the EES (n = 27) or a metallic stent (n = 15). Baseline clinical and angiographic characteristics were similar among both groups. At 6-month follow-up, EES had a lower in-stent late lumen loss (0.10 +/- 0.22 vs 0.85 +/- 0.32 mm, p <0.0001) and in-segment diameter stenoses (20.7 +/- 12.3% vs 37.0 +/- 15.8%, p = 0.002). There was no in-stent restenosis with EES; however, 1 focal distal edge restenosis was present. There was 1 in-stent and 1 in-segment (proximal edge) restenosis in the metallic stent group. There was no stent thrombosis or aneurysm formation at follow-up in either group