Oliver Schlager

Balloon angioplasty versus implantation of nitinol stents in the superficial femoral artery

BACKGROUND Because stent implantation for disease of the superficial femoral artery has been associated with high rates of late clinical failure, percutaneous transluminal angioplasty is preferred for endovascular treatment, and stenting is recommended only in the event of suboptimal technical results. We evaluated whether primary implantation of a self-expanding nitinol (nickel-titanium) stent yielded anatomical and clinical benefits superior to those afforded by percutaneous transluminal angioplasty with optional secondary stenting. METHODS We randomly assigned 104 patients who had severe claudication or chronic limb ischemia due to stenosis or occlusion of the superficial femoral artery to undergo primary stent implantation (51 patients) or angioplasty (53 patients). Restenosis and clinical outcomes were assessed at 6 and 12 months. RESULTS The mean (+/-SD) length of the treated segment was 132+/-71 mm in the stent group and 127+/-55 mm in the angioplasty group. Secondary stenting was performed in 17 of 53 patients (32 percent) in the angioplasty group, in most cases because of a suboptimal result after angioplasty. At 6 months, the rate of restenosis on angiography was 24 percent in the stent group and 43 percent in the angioplasty group (P=0.05); at 12 months the rates on duplex ultrasonography were 37 percent and 63 percent, respectively (P=0.01). Patients in the stent group were able to walk significantly farther on a treadmill at 6 and 12 months than those in the angioplasty group. CONCLUSIONS In the intermediate term, treatment of superficial-femoral-artery disease by primary implantation of a self-expanding nitinol stent yielded results that were superior to those with the currently recommended approach of balloon angioplasty with optional secondary stenting. (ClinicalTrials.gov number, NCT00281060.).

Sustained Benefit at 2 Years of Primary Femoropopliteal Stenting Compared With Balloon Angioplasty With Optional Stenting

Background— Primary stenting with self-expanding nitinol stents of the superficial femoral artery yielded improved morphological and clinical results compared with balloon angioplasty with optional stenting until 12 months in a randomized controlled trial. We now report 2-year data on restenosis and clinical outcomes of these patients. Methods and Results— Of 104 patients with chronic limb ischemia and superficial femoral artery obstructions, 98 (94%) could be followed up until 2 years after intervention for occurrence of restenosis (>50%) by duplex ultrasound and for clinical and hemodynamic outcome by treadmill walking distance and ankle brachial index. Restenosis rates at 2 years were 45.7% (21 of 46) versus 69.2% (36 of 52) in favor of primary stenting compared with balloon angioplasty with optional secondary stenting by an intention-to-treat analysis (P=0.031). Consistently, stenting (whether primary or secondary; n=63) was superior to plain balloon angioplasty (n=35) with respect to the occurrence of restenosis (49.2% versus 74.3%; P=0.028) by a treatment-received analysis. Clinically, patients in the primary stent group showed a trend toward better treadmill walking capacity (average, 302 versus 196 m; P=0.12) and better ankle brachial index values (average, 0.88 versus 0.78; P=0.09) at 2 years, respectively. Reintervention rates tended to be lower after primary stenting (17 of 46 [37.0%] versus 28 of 52 [53.8%]; P=0.14). Conclusions— At 2 years, primary stenting with self-expanding nitinol stents for the treatment of superficial femoral artery obstructions yields a sustained morphological benefit and a trend toward clinical benefit compared with balloon angioplasty with optional stenting.

Long-Segment SFA Stenting—The Dark Sides: In-Stent Restenosis, Clinical Deterioration, and Stent Fractures

Purpose: To determine and compare the rates of in-stent restenosis, late clinical deterioration, and stent fractures in nitinol stents versus Wallstents implanted for suboptimal angioplasty in the superficial femoral artery (SFA). Methods: Interrogation of an angioplasty database identified 286 consecutive patients (178 men; mean age 67±10 years, range 44–87) with severe claudication (n=254) or critical limb ischemia (n=32) who had stents implanted after suboptimal angioplasty over a 5-year period. Wallstents with a mean stented lesion length of 107±71 mm were implanted in 116 patients, while nitinol stents were used in 170 patients: 45 SMART stents (mean stented lesion length 139±88 mm) and 125 Dynalink/Absolute stents (mean stented lesion length 125±84 mm). Patients were followed for in-stent restenosis (>50%) by duplex ultrasound, clinical deterioration by at least 1 Fontaine stage compared to baseline, and stent fractures by biplanar radiography. Results: In-stent restenosis rates at 1, 2, and 3 years were 46%, 66%, and 72% for Wallstents compared to 20%, 36%, and 53% for nitinol stents (p < 0.001), respectively, without significant difference between the 2 nitinol stent groups (p=0.59). Clinical deterioration at 1, 2, and 3 years was found in 10%, 15%, and 18% with Wallstents versus 4%, 5%, and 5% with nitinol stents (p=0.014), respectively, without difference between the 2 nitinol stent groups (p=0.47). Fracture rates were 19% for Wallstents after a mean 43±24 months, 28% for SMART stents after mean 32±16 months, and 2% for Dynalink/Absolute stents after a mean 15±9 months. Conclusions: Intermediate-term in-stent restenosis remains a major problem even with current nitinol stent technology; however, clinical deterioration seems no matter of serious concern with SMART and Dynalink/Absolute stents. Stent fractures may be lower with Dynalink/Absolute stents, but randomized head-to-head comparisons are needed to validate these data.

Perioperative -Blockers for Preventing Surgery-Related Mortality and Morbidity: A Systematic Review and Meta-Analysis

BACKGROUND:Perioperative &bgr;-blockers are suggested to reduce cardiovascular mortality, myocardial–ischemia/infarction, and supraventricular arrhythmias after surgery. We reviewed the evidence regarding the effectiveness of perioperative &bgr;-blockers for improving patient outcomes after cardiac and noncardiac surgery. METHODS:Eleven large databases were searched from the time of their inception until October 2005. Various online-resources were consulted for the identification of unpublished trials and conference abstracts. We included randomized, controlled trials comparing perioperative &bgr;-blockers with either placebo or the standard-of-care. Of the 3680 retrieved titles, 69 met inclusion criteria for analysis. Odds ratios (OR) assuming random effects were computed in the absence of significant clinical heterogeneity. RESULTS:&bgr;-Blockers reduced the frequency of ventricular tachyarrhythmias [OR (cardiac surgery): 0.28, 95% CI 0.13–0.57; OR (noncardiac surgery): 0.56, 95% CI 0.21–1.45], atrial fibrillation/flutter [OR (cardiac surgery): 0.37, 95% CI 0.28–0.48], other supraventricular arrhythmias [OR (cardiac surgery): 0.25, 95% CI 0.18–0.35; OR (noncardiac surgery): 0.43, 95% CI 0.14–1.37], and myocardial ischemia [OR (cardiac surgery): 0.49, 95% CI 0.17–1.4; OR (noncardiac surgery): 0.38, 95% CI 0.21–0.69]. Length of hospitalization was not reduced [weighted mean difference (cardiac surgery): −0.35 days, 95% CI −0.77–0.07; weighted mean difference (noncardiac surgery): −5.59 days, 95% CI −12.22–1.04] and, in contrast to previous reports, &bgr;-blockers did not reduce mortality [OR (cardiac surgery): 0.55, 95% CI 0.17–1.83; OR (noncardiac surgery): 0.78, 95% CI 0.33–1.87], and they had no influence on the occurrence of perioperative myocardial infarction [OR (cardiac surgery): 0.89, 95% CI 0.53–1.5; OR (noncardiac surgery): 0.59; 0.25–1.39]. CONCLUSIONS:&bgr;-Blockers reduced perioperative arrhythmias and myocardial ischemia, but they had no effect on myocardial infarction, mortality, or length of hospitalization.

Progression of Carotid Stenosis Detected by Duplex Ultrasonography Predicts Adverse Outcomes in Cardiovascular High-Risk Patients

Background and Purpose— The progression of carotid stenosis reflects the activity of atherosclerotic disease and may indicate a risk for systemic atherothrombotic complications. We investigated whether progressive carotid stenosis determined by duplex ultrasonography predicts adverse outcomes in cardiovascular high-risk patients. Methods— We prospectively studied 1065 of 1268 consecutive patients initially asymptomatic with respect to carotid disease. Carotid ultrasound investigations at baseline and after a median of 7.5 months (range, 6 to 9 months) were performed to identify patients with progressive stenosis as defined by Doppler velocity criteria. Patients were then followed up clinically for a median of 3.2 years for the occurrence of major adverse cardiovascular events (composite MACEs: myocardial infarction, percutaneous coronary or peripheral interventions, coronary or vascular surgery, amputation, stroke, and all-cause mortality). Results— We found progressive carotid stenosis in 93 patients (9%) by ultrasound and thereafter recorded 495 MACEs in 421 patients (40%) during clinical follow-up. Patients with progressive carotid stenosis had a significantly increased risk for cardiovascular events compared with patients with nonprogressive disease: adjusted hazard ratios and confidence intervals were 2.01 for composite MACEs (95% CI, 1.48 to 2.67, P<0.001), 2.38 for myocardial infarction (95% CI, 1.07 to 5.35, P=0.044), 1.59 for any coronary event (95% CI, 1.10 to 2.28, P=0.011), 2.00 for stroke (95% CI, 1.02 to 4.11, P=0.035), 2.42 for any peripheral vascular event (95% CI, 1.61 to 3.62, P<0.001), and 1.75 for cardiovascular death (95% CI, 1.03 to 2.97, P=0.039). Conclusion— Progression of carotid stenosis within a 6- to 9-month interval detected by duplex ultrasound predicts midterm clinical adverse events of atherosclerosis in high-risk patients affecting the coronary, cerebrovascular, and peripheral circulations.

Exercise training increases endothelial progenitor cells and decreases asymmetric dimethylarginine in peripheral arterial disease: A randomized controlled trial

BACKGROUND Supervised exercise training (SET) is recommended as initial treatment to improve walking capacity in peripheral arterial disease (PAD) patients with intermittent claudication. Various mechanisms by which SET yields beneficial effects are postulated, however data regarding its influence on angiogenesis are scarce. Thus, we designed a prospective randomized controlled trial to study the impact of SET on markers of angiogenesis and endothelial function in PAD. METHODS Forty PAD patients were randomized to SET on top of best medical treatment (SET+BMT) for 6 months versus best medical treatment (BMT) only. Endothelial progenitor cells (EPC) were assessed by whole-blood flow cytometry (co-expression of CD34+ CD133+ KDR+) and cell culture assays (endothelial cell-colony forming units, circulating angiogenic cells, migration assay) at baseline, 3, 6 and 12-months after inclusion. Changes of plasma levels of asymmetric dimethylarginine (ADMA), vascular endothelial growth factor (VEGF), stromal cell-derived factor-1 (SDF-1) and maximum walking distance were determined. RESULTS EPC - measured by flow cytometric and cell culture techniques - increased significantly upon training paralleled by a significant decrease of ADMA when compared to the BMT group (p<0.05). Six months after training cessation, the beneficial effect of SET on EPC diminished, but maximum walking distance was significantly improved compared to baseline and controls (p<0.05). No significant changes were observed for VEGF and SDF-1 plasma levels in time course. CONCLUSIONS SET increases circulating EPC counts and decreases ADMA levels reflecting enhanced angiogenesis and improved endothelial function, which might contribute to cardiovascular risk reduction.

Conventional balloon angioplasty versus peripheral cutting balloon angioplasty for treatment of femoropopliteal artery in-stent restenosis: initial experience.

PURPOSE To prospectively determine whether cutting balloon angioplasty, when compared with conventional balloon angioplasty (CBA), improves morphologic and clinical outcome in patients with femoropopliteal in-stent restenosis. MATERIALS AND METHODS Patients with symptomatic femoropopliteal in-stent restenosis were randomly assigned to undergo CBA or peripheral cutting balloon angioplasty (PCBA) for treatment of lesions up to 20 cm in length. Patients were followed up clinically and with duplex ultrasonography (US) at 1, 3, and 6 months for occurrence of a restenosis of 50% or higher. The Fisher exact test and Mann Whitney U test were used for statistical analyses. RESULTS Forty patients were enrolled; one patient was lost to follow-up. In the remaining patients, CBA was performed in 22 patients; PCBA was used in 17 patients. Average lesion length was 80 mm +/- 68 (standard deviation). Restenosis rates at 6 months were 65% (11 of 17; 95% confidence interval: 42%, 88%) after PCBA versus 73% (16 of 22; 95% confidence interval: 54%, 92%) after CBA (P = .73). Ankle brachial index (0.83 vs 0.75, P = .26) and maximum walking capacity on the treadmill (117 m vs 103 m, P = .97) at 6 months were also not significantly different between the two groups. CONCLUSION PCBA failed to prove superiority compared with CBA for treatment of femoropopliteal in-stent restenosis in this pilot study. In restenotic lesions with an average length of approximately 8 cm, both treatment modalities yielded disappointing 6-month patency rates.

Increasing Carotid Plaque Echolucency is Predictive of Cardiovascular Events in High-Risk Patients

PURPOSE Carotid plaque echolucency seen at ultrasonography (US) is a potential indicator of plaque instability and may help identify patients at risk for major adverse cardiovascular events (MACEs). The authors performed this study to determine whether decreasing gray-scale median (GSM) levels at repeat carotid US examinations are associated with future MACEs. MATERIALS AND METHODS The study was approved by the institutional ethics committee and all patients provided informed consent. The authors prospectively studied 574 patients with carotid plaques of at least 30% from a group of 1268 consecutive patients who were initially asymptomatic with respect to carotid disease. GSM levels were determined with carotid US at baseline and after a median of 7.5 months (range, 6-9 months), and the mean change of the GSM was calculated. Patients were then followed up clinically for a median of 3.2 years for the occurrence of composite MACE. RESULTS During the initial period, the median change in carotid GSM was 2.9 (interquartile range [IQR], -6.9 to 11.0). Of 574 study participants, 230 (40%) showed a reduction of GSM levels and 344 (60%) showed an increase. MACEs were observed in 177 (31%) of the 574 patients. Adjusted hazard ratios for the lowest quartile (GSM change less than -6.9), the second quartile (GSM change between -6.9 and 2.9), and the third quartile (GSM change between 3.0 and 11.0) were 1.71 (95% confidence interval [CI]: 1.09, 2.66), 1.36 (95% CI: 0.86, 2.16), and 1.22 (95% CI: 0.77, 1.95), respectively, compared with the highest quartile (GSM change greater than 11.0) (P = .018). CONCLUSION Increasing echolucency of carotid artery plaques within a 6- to 9-month interval is predictive of midterm clinical adverse events of atherosclerosis.

C-Reactive Protein Predicts Future Cardiovascular Events in Patients With Carotid Stenosis

Background and Purpose— Atherosclerosis is a systemic inflammatory disease. We demonstrated previously that high-sensitivity C-reactive protein (hs-CRP) is associated with short-term progression of carotid atherosclerosis. We now investigated whether baseline levels of hs-CRP predict midterm clinical outcome in these patients. Methods— We prospectively studied 1065 of 1268 consecutive patients who were initially asymptomatic with respect to carotid artery disease and were investigated with serial carotid ultrasound examinations at baseline and after a 6- to 9-month interval. Patients were followed-up clinically for the occurrence of cardiovascular events, a composite of myocardial infarction, percutaneous coronary intervention, coronary artery bypass graft, stroke, and death. Results— We recorded progression of carotid stenosis in 93 patients (9%) after 6 to 9 months, and 381 cardiovascular events in 337 patients (27%) during a median of 3 years of clinical follow-up (interquartile range, 2.5 to 3.5 years). The hs-CRP levels were significantly elevated in patients with progressive carotid stenosis (P<0.001), and hs-CRP was significantly associated with the occurrence of a first future cardiovascular event (P<0.001). Adjusted hazard ratios for a first cardiovascular event for increasing quintiles of hs-CRP were 1.41 (95% confidence interval, 0.92 to 2.17), 1.76 (95% confidence interval, 1.17 to 2.66), 2.22 (95% confidence interval, 1.48 to 3.32), and 2.41 (95% confidence interval, 1.61 to 3.60) as compared with the lowest quintile, respectively. This association was independent of traditional cardiovascular risk factors and the baseline degree of carotid stenosis. Conclusion— Inflammation was associated with morphological and clinical progression of atherosclerotic disease. Patients with elevated levels of hs-CRP exhibit an increased risk for adverse cardiovascular outcome attributable to clinical adverse events of progressive atherosclerotic disease.

Duplex sonography versus angiography for assessment of femoropopliteal arterial disease in a "real-world" setting.

Purpose: To evaluate the agreement of duplex ultrasound (DUS) versus digital subtraction angiography (DSA) for assessment of femoropopliteal arterial disease in a real-world clinical setting. Methods: Consecutive patients with peripheral artery disease who were scheduled for a percutaneous intervention were included in this retrospective study. During an 18-month period, 491 patients (276 men; median age 73 years, interquartile range 64–81) were enrolled. A peak systolic velocity ratio (PSVR) >2.4 was the optimal cutoff for detecting a >50% stenosis by DSA. Findings of preprocedural DUS in the proximal, middle, and distal ipsilateral superficial femoral artery and in the popliteal segment were analyzed for agreement with preprocedural femoropopliteal DSA using kappa statistics. Only the target limb in each patient was analyzed, for a total of 1964 vascular segments. Results: Agreement for the degree of stenosis in 10% increments was only moderate (weighted kappa 0.67, 95% CI 0.65 to 0.69). Using the PSVR >2.4 cutoff, agreement between DUS and DSA for a >50% stenosis was good (kappa 0.79, 95% CI 0.77 to 0.81). Sensitivity, specificity, positive predictive value, and negative predictive value for correctly detecting a >50% stenosis by DUS were 0.81 (0.78 to 0.84), 0.93 (0.91 to 0.94), 0.84 (0.81 to 0.87), and 0.91 (0.87 to 0.95), respectively. Comparable findings were observed within different patient subgroups. Conclusion: Agreement between DUS and DSA in the femoropopliteal segment is only moderate with respect to the absolute degree of stenosis. However, detection of a >50% stenosis can be done with acceptable precision in routine clinical practice using PSVR >2.4 as a threshold.