Assessment of the results of percutaneous transluminal coronary angioplasty using an integrated ultrasound imaging-angioplasty Catheter

To evaluate the results percutaneous transluminal coronary angioplasty (PTCA), intra-vascular ultrasound imaging was performed in 32 proximal coronary arterial segments and in 16 atherosclerotic lesions after PTCA in 13 patients using a 5 Fr balloon catheter with an ultrasound transducer mounted just proximal to the balloon. Simultaneous angiographic measurements of vessel diameter were also performed using electronic calipers from contrast cine angiograms. There was good correlation between ultrasound and angiographic minimum luminal diameters of the normal proximal vessel (y = 0.59x + 1.49, r = 0.70, P<0.01, n = 32). However, the luminal diameter measured by intravascular ultrasound was significantly greater than when measured by contrast angiography (2.81±0.10 vs. 2.34±0.12mm, n = 16, P<0.001, mean ±SEM). Post-PTCA, there was good correlation between ultrasound and angiographic minimum luminal diameters of the lesion (y = 0.62x + 1.42, r=0.76, P<0.001, n = 16), but again luminal diameters were significantly greater when measured by intravascular ultrasound compared to contrast angiography (2.61±0.08 vs. 1.89 ± 0.10mm, n = 16, P<0.001). Furthermore, residual stenosis was significantly less when determined by intravascular ultrasound than by contrast angiography (7.3±2.0 vs. 18.1 ± 2.1%, n = 16, P<0.001). Intravascular ultrasound was able to detect coronary calcification that was not evident by contrast coronary angiography in 8 of 16 lesions. Post-PTCA, dissection was evident in four lesions by ultrasound, whereas dissection was appreciated in only three lesions by contrast angiography. We conclude that intravascular ultrasound can accurately measure the luminal diameter of coronary arteries both before and after PTCA and reveals more information about the lesion characteristics than does conventional contrast angiography.     

Micro stent,™ quantitative coronary angiography,and procedural results

Micro stent™ (MS) is a radiopaque stainless steel balloon expandable intracoronary stent. The stent is mounted on a rapid-exchange delivery system. From August 1994–March 1995, 127 MS were implanted in 85 patients (pts, 1.5 stents/pt, 85 in native vessels and 42 in bypass vein grafts, 61 male and 24 female, age 33–77 yr, mean age 61 ± 10 yr). Pts studied were scheduled for either elective PTCA (n = 62, 73%) or PTCA for acute myocardial infarction (n = 23, 27%). Elective stent implantation was performed in 45 pts (53%). An MS was implanted because of a suboptimal balloon angioplasty result in 26 pts (31%). The stent was implanted because of threatened or acute vessel closure after balloon angioplasty in 14 pts (16%). During the procedure, 500 mg aspirin and 2 × 7,500 units of heparin were administered intravenously, followed by systemic heparinization for 48 hr. Pts were discharged with 100 mg aspirin daily (n = 50, 59%), or anticoagulant drugs and 100 mg aspirin daily (n = 19, 22%), or anticoagulant drugs only (n = 16, 19%). Angiographic results were analyzed with computer-assisted quantitative coronary arteriography. Angiographic success (defined as a residual stenosis of <30%) was achieved in 124 of 127 attempts (98%). The mean minimal luminal diameter of the target lesions increased from 0.88 ± 0.79 mm before stent implantation to 3.08 ± 0.56 mm (P < 0.001). The percentage of diameter stenosis was reduced from 77.9 ± 20.9% before to 13.3 ± 10.5% (P < 0.001) after stent implantation. The average initial gain was 2.53 ± 1.37 mm. The procedural success rate (defined as a residual stenosis of <30% without occurrence of major clinical events within 3 wk after procedure) was 84%. Major clinical events included: death 1 pt (1%); cerebrovascular accident, 1 pt (1%); subacute stent closure, 5 pts (6%); coronary artery bypass grafting, 3 pts (4%); false femoral aneurysm, 2 pts (2%). The initial results of Micro stent implantations are promising. No anticoagulant therapy was given to most of the patients (59%). Few vascular and bleeding complications were observed. However, at this stage, no data about the restenosis rate after implantation of a Micro stent are available. © 1996 Wiley-Liss, Inc.     

Predictors of short term clinical and angiographic outcome after coronary angioplasty for acute myocardial infarction

Coronary angioplasty is an effective method to achieve myocardial reperfusion in acute myocardial infarction (AMI). We reviewed our experience in 132 patients (pts) who underwent percutaneous transluminal coronary angioplasty (PTCA) of a totally occluded infarct-related artery (IRA) within 24 h after the onset of symptoms (mean delay 10±7 h), in order to identify the predictors of primary success and of major complications. PTCA was successfully performed in 113 patients (86%). Failure without complications occurred in 12 patients (8.4%); untoward events (death and emergency CABG) occurred in seven patients (5.3%). Pts in the failure group were more likely to have cardiogenic shock (53 vs. 8.8%, P<.0005), longer time to reperfusion (15±6 vs. 9±6 h, P<.0005), lower ejection fraction (EF) (42±16 vs. 54±12%, P<.0005), multivessel disease (74 vs. 43%, P<.03), and a smaller IRA diameter (2.8±0.6 vs. 3.1± 0.6 mm, P<.03). Sex, age, previous bypass surgery, previous thrombolytic treatment, IRA, and infarct location were similar in both groups. Absence of cardiogenic shock (P<.0001), decreasing time to reperfusion (P<.005) and increasing EF (P<.02) were independent predictors of successful PTCA. Presence of cardiogenic shock (P<.0001) and decreasing EF (<.05) were independent predictors of untoward events. Repeat angiography was performed 24 h after the procedure in the success group. Angiographic deterioration (stenosis ? 50% and/or TIMI flow grade ? 1) was present in 18 pts (16%), among whose 5 pts (4.4%) had re-occlusion of the IRA. Pts with early angiographic deterioration were more likely to have a lower IRA diameter (2.8±0.5 vs. 3.1±0.6 mm, P<.02). Conclusion: Emergency PTCA is an effective method for establishing reperfusion in AMI. Pts with high-risk baseline characteristics show the highest rate of untoward events, but are the most likely to benefit from aggressive reperfusion therapy. © 1995 Wiley-Liss, inc.     

Rotational atherectomy for in-stent restenosis: acute and long-term results of the first 100 cases

Objectives. This study evaluated the clinical safety and long-term results of rotational atherectomy (RA) followed by low-pressure balloon dilatation (percutaneous transluminal coronary angioplasty [PTCA]) for the treatment of in-stent restenosis (ISR).Background. In-stent restenosis is associated with a high incidence of recurrence after interventional treatment. Because ISR is due to neointimal hyperplasia, rotational ablation may be a more effective treatment than PTCA.Methods. Between November 1995 and November 1996, 100 consecutive patients with first-time ISR were treated by RA. Quantitative coronary angiography and intravascular ultrasound (IVUS) were used to analyze the acute procedural results. The incidence of repeat in-stent restenosis and target vessel revascularization (TVR) at follow-up was determined.Results. Procedural success without any major in-hospital complications was achieved in 100% of cases. Slow flow was observed in 3% and creatine kinase-MB enzyme elevation >3× normal occurred in 2%. The mean burr-to-artery ratio was 0.68 ± 0.18 and adjuvant balloon dilatation was performed at 4.2 ± 2.1 atm. Minimum luminal diameter increased from 0.86 ± 0.28 mm to 1.89 ± 0.21 mm after RA and to 2.56 ± 0.29 mm after adjunct PTCA. Quantitative IVUS analysis showed that 77% of the luminal gain occurred due to rotational ablation of the restenotic tissue and only 23% occurred after adjunct balloon dilation, and further stent expansion did not contribute to the luminal enlargement. At a mean follow-up of 13 ± 5 months, repeat in-stent restenosis occurred in 28% of patients with TVR of 26%. Univariate predictors of repeat restenosis were burr-to-artery ratio <0.6, ISR in <90 days of stenting, ostial lesion, stent for a restenotic lesion and diffuse type ISR.Conclusions. Rotational atherectomy is a safe and feasible technique for treatment of ISR and is associated with a relatively low recurrent restenosis in comparison to historical controls of balloon angioplasty.     

Simultaneous stent implantation to treat bifurcation stenoses in the pulmonary arteries: Initial results and long‐term follow up

Background : Balloon angioplasty of bifurcating pulmonary artery (PA) stenoses is often inadequate, and stent treatment often requires simultaneous implantation of two stents. This study evaluates initial results and long‐term follow up of transcatheter stent placement in bifurcating PAs. Methods : This is a retrospective review of patients (pts) who had bifurcating PA stents placed in main and lobar branches from 1993 to 2007. Results : Forty‐nine pts had bifurcating PA stents placed at a median age of 10.9 years (range 1–43 years). The mean minimum vessel diameter increased from 5.7 ± 2.5 mm to 11.0 ± 3.6 mm (P < 0.001), the mean gradient across the stenoses decreased from 37.0 ± 26.9 to 9.2 ± 13 mm Hg (P < 0.001), whereas the mean RV:FA ratio decreased from 0.76 ± 0.29 to 0.53 ± 0.24 (P < 0.001). There was one death due to severe pulmonary hemorrhage. F/U data were available in 38 pts (mean duration 6.3 ± 4.1 years, range 1.2–13.1 years). Thirty pts underwent repeat catheterizations (mean 2.3 ± 2.2 years poststent), with 26 requiring further interventions: Fifteen had balloon angioplasty alone and 11 had additional stents placed. There were no complications at f/u catheterization. Six pts underwent further palliative surgeries, although none for repair of branch PA stenoses. Conclusions : Simultaneous transcatheter placement of bifurcating PA stents provides immediate gradient relief of bifurcating stenoses in the proximal or lobar branch PAs and reduces RV systolic pressure. Further interventions can be safely performed in future procedures, and the presence of stents does not complicate future surgeries. © 2009 Wiley‐Liss, Inc.     

Discordant results of visual and quantitative estimates of stenosis severity before and after coronary angioplasty

The ability to accurately estimate the severity of epicardial coronary stenoses is critical in the assessment of the immediate and long-term results of percutaneous transluminal coronary angioplasty (PTCA). We prospectively compared visual estimates, performed by experienced interventional cardiologists, with computerized quantitative angiographic measurements of stenosis severity in a group of patients (n = 305) before, immediately after and 6 months after PTCA. Before PTCA the visual estimate of the mean (±SD) percentage stenosis severity, 80.6 (±9.7)%, was significantly (P<0.001) higher than the equivalent value, 73.4 (±11.1)%, obtained with use of quantitative angiography. Immediately after PTCA the visual estimate of the mean residual stenosis, 18.8 (±12.3)%, was significantly (P<0.0001) lower than the equivalent quantitative estimate, 37.4 (±14)%. Additionally, the residual stenosis was more frequently (18% vs. 3%) classified as significant (>50%) by quantitative angiography. At follow-up, quantitative measurements of stenosis severity showed a Gaussian distribution with a mean of 54.8 (±21)%, whereas visual estimates had a bimodal distribution with populations greater than 70% and less than 50%. Visual estimates provide an inaccurate assessment of the immediate and medium term results of PTCA. Quantitative measurements suggest that the immediate results of PTCA are frequently misclassified as successful by the operator. Conversely, restenosis rates are underestimated by the operators suggesting that a more objective method must be used in trials to assess the impact of new therapies on the rate of restenosis.     

Stenting in chronic coronary occlusion (SICCO): A randomized,controlled trial of adding stent implantation after successful angioplasty

Objectives. This study investigated whether stenting improves long-term results after recanalization of chronic coronary occlusions.Background. Restenosis is common after percutaneous transluminal coronary angioplasty (PTCA) of chronic coronary occlusions. Stenting has been suggested as a means of improving results, but its use has not previously been investigated in a randomized trial.Methods. We randomly assigned 119 patients with a satisfactory result after successful recanalization by PTCA of a chronic coronary occlusion to 1) a control (PTCA) group with no other intervention, or 2) a group in which PTCA was followed by implantation of Palmaz-Schatz stents with full anticoagulation. Coronary angiography was performed before randomization, after stenting and at 6-month follow-up.Results. Inguinal bleeding was more frequent in the stent group. There were no deaths. One patient with stenting had a myocardial infarction. Subacute occlusion within 2 weeks occurred in four patients in the stent group and in three in the PTCA group. At follow-up, 57% of patients with stenting were free from angina compared with 24% of patients with PTCA only (p < 0.001). Angiographic follow-up data were available in 114 patients. Restenosis (≥50% diameter stenosis) developed in 32% of patients with stenting and in 74% of patients with PTCA only (p < 0.001); reocclusion occurred in 12% and 26%, respectively (p = 0.058). Minimal lumen diameter (mean ± SD) at follow-up was 1.92 ± 0.95 mm and 1.11 ± 0.78 mm, respectively (p < 0.001). Target lesion revascularization within 300 days was less frequent in patients with stenting than in patients with PTCA only (22% vs. 42%, p = 0.025).Conclusions. Stent implantation improved long-term angiographic and clinical results after PTCA of chronic coronary occlusions and is thus recommended regardless of the primary PTCA result.     

Exaggerated luminal loss a few minutes after successful percutaneous transluminal coronary angioplasty in patients with recent myocardial infarction compared with stable angina: An intracoronary ultrasound study

This study investigates the mechanisms of exaggerated acute luminal loss after successful coronary angioplasty in patients with recent myocardial infarction compared with stable angina by angiography and intracoronary ultrasound (ICUS). We studied 15 consecutive patients (group 1) who, after a successful thrombolysis for myocardial infarction, underwent delayed (8 ± 2 days after the myocardial infarction) successful balloon coronary angioplasty. Group 1 patients were individually matched with 15 stable angina patients (group 2). The percentage of stenosis and acute luminal loss were measured by quantitative coronary analysis. The ultrasound characteristics of lumen pathology were described as soft, hard, calcified, eccentric, concentric, thrombotic, and dissection lesions. Matching by stenosis location, reference diameter, sex, and age resulted in 2 comparable groups of 15 lesions with identical baseline characteristics. Immediately after percutaneous transluminal coronary angioplasty (PTCA), the minimal luminal diameter increased from 0.5 ± 0.3 mm to 2.4 ± 0.3 mm and from 0.5 ± 0.2 mm to 2.4 ± 0.3 mm in groups 1 and 2, respectively. Similar balloon sizes were used in both groups. The acute luminal loss (the difference between the maximal dilated balloon diameter and the minimal luminal diameter) immediately after PTCA was 0.4 ± 0.2 mm and 0.3 ± 0.3 mm (14 ± 8% and 10 ± 11% of balloon size) (P = not significant [NS]) in groups 1 and 2, respectively. After ICUS (mean 24 min after the last balloon deflation), the acute luminal loss was 0.9 ± 0.3 mm and 0.5 ± 0.4 mm (29 ± 11% and 17 ± 8% of balloon size) (P = 0.01) in groups 1 and 2, respectively. There was a significantly higher prevalence of intracoronary thrombus formation as detected by ICUS in group 1 compared with group 2 (80% vs. 20%; P < 0.001). In matched groups of successfully treated coronary angioplasty, patients with recent myocardial infarction had a similar magnitude of acute gained luminal loss immediately after the procedure. However, an exaggerated luminal loss a few minutes after the last balloon deflation in patients with recent myocardial infarction was noted because of mural thrombus formation compared with patients with stable angina. Cathet. Cardiovasc. Diagn. 41:32–39, 1997. © 1997 Wiley-Liss, Inc.     

Discrepancy between visual estimation and computer-assisted measurement of lesion severity before and after coronary angioplasty

One hundred fourteen coronary stenoses were quantified before and after percutaneous transluminal coronary angioplasty (PTCA) using a semi-automated digital system. The values obtained were considered as standard for comparison with visual estimation by the PTCA operator as well as by independent consensus-reading. The measured percent stenosis was 62.7 ± 13.7% before and 27.7 ± 12.4% after angioplasty. Before PTCA, the operator consistently overestimated stenosis severity (87.8 ± 8.5%, P < 0.0001) and consensus-reading reduced but did not eliminate this overestimation (78.0 ± 12.3%, P < 0.05). The error in visual estimation was inversely correlated with the measured degree of stenosis: coefficients were –0.79 (P < 0.0001) and –0.51 (P < 0.0001) for operator and consensus-readers, respectively. After PTCA, the operator underestimated the residual stenosis (21.2 ± 9.9%, P < 0.0001) but there was no systematic bias by consensusreading (29.4 ± 12.0%, NS). Again the error in visual estimation was inversely correlated with the measured degree of residual stenosis : coefficients were –0.76 (P < 0.0001) and –0.58 (P < 0.0001) for operator and consensus-reading, respectively. In conclusion, the operator overestimates lesion severity before and underestimates moderate residual stenoses after PTCA, a problem only partially corrected by independent consensus-readers.     

Effects of transluminal coronary angioplasty on left ventricular systolic and diastolic function at rest and during exercise

The left ventricular global and regional systolic function, ventricular volumes, and peak diastolic filling rate (PDFR) were studied in 30 patients with coronary artery disease, before and 2 to 5 days after transluminal coronary angioplasty (PTCA), utilizing equilibrium radionuclide angiography at rest and during exercise. At rest, the global ejection fraction (EF) was unchanged before (60 ± 9%) and after PTCA (62 ± 10%). During exercise, global EF increased from 59 ± 11% pre PTCA to 67 ± 10 post PTCA (p < 0.001). Twenty-two patients had abnormal EF response to exercise pre PTCA, versus seven post PTCA (p < 0.001). Improvements in exercise regional EF paralleled the changes in global EF. End-systolic volume was unchanged at rest but decreased significantly with exercise post PTCA (60 ± 36 ml pre vs 49 ± 32 ml post PTCA, p < 0.01). At rest, the PDFR was unchanged post PTCA (2.4 ± 0.9 end-diastolic volume (EDV)/sec pre vs 2.5 ± 0.8 EDV/sec post). During exercise, PDFR increased from 2.1 ± 0.7 EDV/sec pre PTCA to 2.5 ± 0.7 EDV/sec post PTCA (p < 0.02). In conclusion, in patients with coronary artery disease, successful PTCA improves global and regional systolic function during exercise. Diastolic function is improved during exercise, a fact not previously demonstrated.     

Restenosis and its determinants in first and repeat coronary angioplasty

Restenosis is the main problem limiting long-term success ofpercutaneous transluminal coronary angioplasty (PTCA) and ismost accurately evaluated by follow-up angiography. We comparedthe primary and long-term results of angioplasty in 268 consecutivepatients (293 segments) with first PTCA (PTCA 1, angiographicfollow-up 98%) and in 66 patients (76 segments) with repeatPTCA after restenosis (PTCA 2, angiographic follow-up 92%).Forty clinical, angiographic and procedural factors were assessedin relation to outcome. Primary success rate was higher in PTCA2 (91% vs 67.5%) and major complications were fewer (4.5% vs16%).Higher inflation pressure (7.9 ± 2.3 vs 6.8 ±1.8 atm, P<0.005) and larger balloons (3.5 ± 0.5 vs3.2 ± 0.5mm, P< 0.005) were used for PTCA 2, resultingin lesser residual stenosis (33 ± 16± vs 40 ±18%, P <0.05). Restenosis rate (>70%) after PTCA 1 andafter PTC A 2 (27% vs 36%, P = NS) and the mean time to recurrence(4.7 vs 5.3 months, P = NS) were similar. Procedural factorswere the main determinants of long-term success in primary PTCA.The restenosis risk was independently related to residual stenosis>45% (P<0.001), variant angina (P<0.05) and multivesseldisease (P<0.05) after PTCA 1 and to male sex (P<0.001)and higher inflation pressure (P<0.05) after PTCA 2. Mildto moderate intimal tearing was associated with less restenosisafter PTC A 1, but not after PTCA 2. Including 9 patients (10segments) with a third PTCA, 70% of the 66 patients with repeatPTCA had a successful long-term outcome. Repeat angioplastyshould therefore be considered as an integral part of PTCA therapy.Restenosis however remains a major concern. An optimal primaryresult with a minimal residual stenosis is decisive for firstPTCA, whereas avoidance of a dissection by using lower inflationpressure on a restenosis might improve the long-term outcomeof repeat PTCA.     

Stent implantation for relief of pulmonary artery stenosis: Immediate and short-term results

Our objective was to assess the immediate and short-term results of stent implantation to relieve pulmonary artery stenosis (PAS). Thirty-seven patients underwent an attempt at stent implantation at a median age of 7.0 years (range, 0.8–31.4 years) and a median weight of 20.5 kg (range, 7.4–85 kg). Twenty-two patients had previous tetralogy of Fallot repair. A total of 55 stents were implanted successfully in 36 patients. The peak systolic gradient across the stenotic segment decreased from a mean of 43 ± 20.4 mmHg prestent to 13 ± 13.9 mmHg (P < 0.001) poststent. The diameter of the narrowest segment increased from a mean of 4.8 ± 1.6 mm to 10.5 ± 2.6 mm (P < 0.001). The right ventricular-to-aortic mean systolic pressure ratio decreased from 0.74 ± 0.2 to 0.52 ± 0.19 (P < 0.001). Complications included balloon rupture prior to full stent expansion in 4 patients (in 2 patients the stent was positioned in the superior vena cava, and in 2 in the inferior vena cava), distal migration of a stent which was successfully retrieved at surgery 1 mo later in 1 patient, and tethering of the stent to the balloon requiring surgical removal in 1 patient. One patient died several hours after stent placement. Sixteen patients underwent repeat catheterization at a mean follow-up interval of 0.9 ± 0.5 years (range, 0.2–2.0 years). The mean gradient across the stent for these 16 patients was 26.7 ± 19.8 mmHg, and there was no change in the mean diameter (9.4 ± 3.2 mm). Two patients developed stenosis related to neointimal proliferation at the stent site which was redilated successfully. In conclusion, stent implantation is generally safe and effective in relieving PAS. © 1996 Wiley-Liss, Inc.     

Micro stent I,initial results,and six months follow-up by quantitative coronary angiography

The Micro stent^TM (MS) is a balloon expandable stent that allows the treatment of stenoses in distal and tortuous coronary arteries. This prospective study was performed to evaluate initial and late results of MS implantations. A total of 127 MS (101 in native coronary arteries and 26 in saphenous vein grafts) were implanted in 85 patients (1.5 stents/pt, 65 male, and 20 female, age 62, ±10 yr) with angina pectoris class II-III: 21 (25%), angina pectoris class IV: 41(48%), and acute myocardial infarction: 23 (27%). Indications per segment treated (n=93): elective: 49 (53%); suboptimal balloon angioplasty (PTCA) result: 33(35%); bailout: 11 (12%). The patients were discharged with 100 mg of aspirin daily unless other indications for oral anticoagulants were present. Procedural success (diameter stenosis of 30% without the occurrence of clinical events within 3 wk) was 85%. Early clinical events (<3 wk included: death:1%; subacute closure: 5%; coronary artery bypass surgery (CABG): 1%; vascular complications: 4%. Late clinical events (3 wk-6 mo) included: acute myocardial infarction:3%, PTCA 5%, CABG 3%, angina class III-IV: 4%. Quantitative angiographic results were: the minimum lumen diameter increased from 0.90 ± 0.72 before to 3.05 ± 0.48 mm (<P0.001) after stent implantation. At follow-up, which was 5.5 mo ± 1.1 mo, 61/79 pts (77%), the loss in diameter was 0.90 ± 0.68 mm. The net gain was 1.26 ± 0.90 mm. The restenosis rate (diameter stenosis > 50% at FU) was 13%. This study demonstrates high procedural and late success rates of Micro stent implantations. Cathet. Cardiovasc. Diagn. 43:19-27, 1998. © 1998 Wiley-Liss, Inc.     

Excimer laser angioplasty vs. balloon angioplasty in saphenous vein bypass grafts: Quantitative angiographic comparison of matched lesions

Technologies which ablate or debulk tissue may result in better angiographic outcomes by altering the elastic properties of the vessel wall. Accordingly, the procedural outcomes of 88 vein graft lesions treated by either excimer laser angioplasty with adjunct balloon angioplasty (PELCA + PTCA, n = 44) (Spectranetics CVX-300, 1.4-, 1.7-, or 2.0-mm catheters) or balloon angioplasty alone (PTCA, n = 44) were analyzed by quantitative angiography (Cardiac Measurement System). Lesions were individually matched for vessel position, reference diameter (RD), and minimal luminal diameter (MLD). Matching was deemed adequate as the preprocedure MLD (PELCA + PTCA, 1.14 ± 0.48 mm; PTCA, 1.20 ± 0.47 mm) and RD (PELCA + PTCA, 3.23 ± 0.56 mm; PTCA, 3.25 ± 0.57 mm) were not significantly different. There were also no significant differences between PELCA + PTCA- and PTCA-treated lesions with respect to patient age, graft age, lesion length, symmetry, and plaque area. Balloon diameter at maximal inflation was 2.77 ± 0.55 mm (PELCA + PTCA group) and 2.84 ± 0.59 mm (PTCA group), P = NS. Final MLD postprocedure was 2.17 ± 0.54 mm and 2.19 ± 0.55 mm for PELCA + PTCA- and PTCA-treated lesions (P = NS), respectively. Vessel stretch [(balloon diameter − MLD pre)/RD], elastic recoil [(balloon diameter − MLD post)/RD], and acute gain [(MLD post − MLD pre)/RD] were calculated and normalized for vessel size (RD). Vessel stretch (PELCA + PTCA, 0.60 ± 0.22; PTCA, 0.59 ± 0.24; P = NS), elastic recoil (PELCA + PTCA, 0.28 ± 0.18; PTCA, 0.26 ± 0.16), and acute gain (PELCA + PTCA, 0.34 ± 0.24; PTCA, 0.31 ± 0.23; P = NS) were not significantly different between the two treatment groups. In a matched population of successfully treated vein graft lesions, PELCA + PTCA did not reduce elastic recoil or improve immediate angiographic outcome, as compared with PTCA alone. © 1996 Wiley-Liss, Inc.     

The significance of platelet activation in rheumatoid arthritis

We evaluated the significance of platelet activation in patients with rheumatoid arthritis (RA). The expression of CD62P and CD63 by platelets was determined using flow cytometry in 18 active RA patients, 10 remission RA and 15 normal controls. Meanwhile, the erythrocyte sedimentation rate (ESR) and C-reactive protein was also determined in all groups. The expression of CD62P in active RA patients (11.88 ± 2.47%) was significantly higher than that in remission RA group (2.85 ± 1.60%; P < 0.01) and control group (2.78 ± 1.04%; P < 0.01). The expression of CD63 in active RA patients (9.90 ± 3.02%) was significantly higher than that in remission RA group (4.11 ± 2.00%; P < 0.01) and control group (4.13 ± 1.85%; P < 0.01). The level of CRP (54.33 ± 23.35 mg/l) and ESR (86.06 ± 33.67 mm/h) in active RA patients was higher than that in remission RA group (2.55 ± 1.01 mg/l, 14.70 ± 4.57 mm/h; P < 0.01 for both) and normal control group (3.21 ± 2.18 mg/l, 12.25 ± 5.05 mm/h; P < 0.01 for both). There was a positive correlation between CD62P and ESR (r = 0.5224, P < 0.01) and also a positive correlation between CD62P and CRP (r = 0.7048, P < 0.01) as well as between CD63 and ESR (r = 0.4476, P < 0.05) but no correlation between CD63 and CRP. Platelet activation may be a sign of RA exacerbation.     

Original studies: Comparison of angiography and intravascular ultrasound for the assessment of lumen size after coronary stent placement: Impact of dilation pressures

This study was designed to assess the extent of potential discrepancies between intravascular ultrasound (IVUS) and quantitative coronary angiography (QCA) measurement of intrastent minimal luminal diameter and to evaluate the impact of dilation pressures and the balloon:artery ratio on the assessment of the minimal lumen diameter (MLD) by these imaging modalities. IVUS is recommended as an adjunct to angiography to assess stent expansion; however, the extent of potential discrepancies between the two imaging modalities is not well defined. Included were 225 patients in whom coronary Palmaz-Schatz stents were successfully placed after PTCA. IVUS and QCA were performed at the end of the intervention. We compared the MLD assessed by QCA and IVUS in the instent and reference site. The MLD assessed by IVUS and QCA were 2.68 ± 0.41 mm and 3.08 ± 0.47 mm (P < 0.001), respectively, at the tightest intrastent site and 3.19 ± 0.50 mm and 3.17 ± 0.52 ns at the reference site. There was a correlation between the dilation pressure and the difference between QCA- and IVUS-based intrastent MLD measurement (y = −0.05x + 1.11; r = −0.53; P < 0.0001). At low dilation pressures, a significant difference beween the image modalities was found, but after high dilation pressures no discrepancies were detected. No relation was found with the balloon:artery ratio. These data provide clear evidence that in the case of low-pressure dilation, the exclusive reliance on data obtained by QCA will not yield sufficiently accurate information on intrastent MLD, whereas after high dilation pressure, the differences between the imaging modalities are minimized. Cathet. Cardiovasc. Diagn. 42:113–119, 1997. © 1997 Wiley-Liss, Inc.     

Repeat balloon dilation of congenital valvar aortic stenosis: Immediate results and midterm outcome

While balloon dilation (BD) has become the initial treatment for congenital valvar aortic stenosis (CVAS) at many institutions, repeat BD for recurrent obstruction has been reported only in a few. Between January 1985 and December 1996, 298 patients (70 neonates) underwent BD, 34 of whom underwent a repeat BD without mortality. A greater proportion of neonates had a repeat BD (26% vs. 8%, P < 0.001). At repeat BD (1 day–7.5 years post initial BD), the mean peak-to-peak gradient was reduced from 67 ± 24 to 36 ± 16 mm Hg (P < 0.0001). Aortic regurgitation (AR) increased immediately in 26%, being moderate or more in 24%. During a mean follow-up of 5.2 years, there was one surgically related death. Of the 33 survivors, 6 had surgery for residual stenosis and/or AR. Among the remaining 27 patients, 96% were asymptomatic, the peak instantaneous aortic valve Doppler gradient was 50 ± 15 mm Hg with AR absent in 8%, mild in 62%, and moderate or more in 31%. In conclusion, repeat BD is effective and without mortality. AR was at least moderate in 24% of patients immediately after a second BD. Repeat BD was more common in patients who underwent the initial BD as neonates. Cathet. Cardiovasc. Intervent. 47:47–51, 1999. © 1999 Wiley-Liss, Inc.     

Rotational atherectomy with a new device: Initial clinical experience

The Bard Atherectomy Catheter is a new rotational atherectomy device that consists of a flexible, hollow, thin-walled cutting catheter that, while rotated at 1,500 revolutions per minute, is advanced across the lesion over a special spiral guidewire system. We report the initial clinical experience with this device in 20 peripheral lesions in ten patients. The majority of patients were treated for limb salvage. All lesions were successfully intervened on by atherectomy followed by adjunctive balloon angioplasty. A reduction to less than 50% stenosis was achieved in 13 of the 20 lesions (65%) after atherectomy but in all 20 lesions (100%) after adjunctive angioplasty for all lesions and stenting for dissections in two. Baseline minimal lesion lumen diameter was 0.8 ± 0.7 mm with a reference vessel diameter of 4.2 ± 1.7 mm (75 ± 21% stenosis). The lumen improved to 2.0 ± 0.8 mm (45 ± 19% stenosis) (P < 0.001) following atherectomy and to 3.9 ± 1.9 mm (13 ± 16% stenosis) (P < 0.001) after adjunctive angioplasty. The average weight of removed atheroma was 45 ± 58 mg. All ten patients had initial improvement in symptoms. At 6 months follow-up there was persistent improvement in eight patients and two subjects had undergone amputations. Our early clinical experience with this low profile, flexible atherectomy device, that enables extraction of a large amount of atheroma, suggests that it will become a valuable addition to current atherectomy technologies in small- and medium-sized vessels. The value of this device in coronary vessels is under investigation. © 1996 Wiley-Liss, Inc.     

Risk of preangioplasty occlusion and myocardial infarction in one-vesseldisease patients scheduled for percutaneous transluminal coronary angioplasty

Coronary occlusion or myocardial infarction occurred in 50 of 394 (13%) one-vesseldisease patients awaiting percutaneous transluminal coronary angioplasty (PTCA). To identify risk factors for these events, we first matched the 37 patients whdemonstrated occlusion on the immediate preangioplasty repeat angiogram with 37 patients who did not. Matching was based on the time interval between angiograms, the date of the procedure, and the site of the lesion. Preangioplasty occlusion patients did differ from controls by age (47 ± 11 vs 54 ± 8 years, P< <.01), smoking status (34/37 vs 24/37, P <.01), and angina class (2.6 ± 1.0 vs 2.3 ± 0.7, P < .10) at the time of the first angiogram. Second, we pooled the data of the 37 preangioplasty occlusion patients with those of the 13 patients with preangioplasty myocardial infarction. The 50 cases with complication (coronary occlusion or myocardial infarction) were younger (47 ± 12 vs 54 ± 8 years, P < .01), more often smokers (42/50 vs 24/37, P <.05), and more symptomatic (2.7 ± 0.8 vs 2.3 ± 0.7, P <.05) than the 37 controls. This study suggests that young smokers with severe angina are at high risk of preangioplasty occlusion and/or myocardial infarction; prompt management of these patients, when considered for PTCA, seems advisable.