Abrupt vessel closure after directional coronary atherectomy. The U.S. Directional Atherectomy Investigator Group.

From October 1, 1986 to December 31, 1989 directional coronary atherectomy was performed during 1,020 procedures (1,140 lesions) at 14 clinical centers. Abrupt vessel closure, defined as a total coronary occlusion or subtotal occlusion associated with clinical evidence of myocardial ischemia, occurred in 43 procedures (4.2%). It developed in the catheterization laboratory in 34 patients, but was delayed 1 to 96 h after directional atherectomy in 9 patients. By univariate analysis the incidence of abrupt closure was higher in directional atherectomy of de novo lesions (p less than 0.001), lesions in the right coronary artery (p = 0.001) and diffuse lesions (p = 0.04). The incidence of abrupt closure tended to be lower in directional atherectomy of saphenous vein grafts as opposed to native coronary arteries (1.6% vs. 4.4%; p = 0.08). Clinical findings during abrupt closure included severe angina in 26 patients, myocardial infarction in 17 patients, hypotension in 5 patients and death in 2 patients. Balloon angioplasty was attempted in 32 patients after abrupt vessel closure. In 16 patients balloon angioplasty resulted in initial resolution of the closure episode, although 1 patient died 96 h after the procedure. Fifteen of 16 patients without initial improvement after balloon angioplasty underwent coronary bypass operation; 9 additional patients with abrupt closure were referred directly for bypass operation. It is concluded that abrupt vessel closure develops relatively infrequently after directional coronary atherectomy. In the absence of severe coronary dissection, abrupt closure after directional atherectomy may be effectively managed with balloon angioplasty in some cases, although coronary bypass operation is often required.     

Comparison of dissection rates and angiographic results following directional coronary atherectomy and coronary angioplasty

Directional coronary atherectomy is a new percutaneous transluminal technique for treating occlusive coronary artery disease. In this study, angiographic results (i.e., residual stenosis and angiographic evidence of postprocedure dissection) after directional coronary atherectomy and balloon angioplasty were compared. The atherectomy group consisted of 91 lesions in 83 consecutive patients who underwent either left anterior descending artery or right coronary artery atherectomy. The angioplasty group consisted of 91 lesions in 84 patients that were matched with the atherectomy lesions with respect to vessel and whether the lesion was a restenosis lesion. The mean preprocedure diameter stenosis was 76% in both groups as measured quantitatively with electronic calipers. After the procedure, the mean residual diameter stenosis of the atherectomy lesions was 13 +/- 17%, whereas for the angioplasty lesions it was 31 +/- 18% (p less than 0.001). Success rates in both groups were similar (94.5 and 93.4%, respectively). The incidence of postprocedure dissection was 11% in the atherectomy group and 37% in the angioplasty group (p less than 0.0001). Directional coronary atherectomy results in significantly improved postprocedure angiographic appearances due to significantly less severe residual stenosis and lower incidence of dissection.     

Morphological effects on in-stent restenosis assessed by intravascular ultrasound imaging.

The purpose of this study was to evaluate the rupture and dissection of the vessel wall immediately after balloon dilatation by intravascular ultrasound (IVUS) imaging and to predict restenosis in patients who underwent subsequent coronary stent implantation. Stent implantation improves the long-term results of coronary angioplasty by reducing lesion elastic recoil and arterial remodeling. However, several studies have suggested that neointimal hyperplasia is the cause of instant restenosis. We recruited 60 patients in whom IVUS studies were performed immediately after successful balloon dilatation and just before stent implantation. We compared IVUS parameters with 6-month follow-up quantitative coronary angiography. This was performed in 51 lesions of 51 patients (85%). Qualitative analysis included assessment of plaque composition, plaque eccentricity, plaque fracture and the presence of dissection. In addition, minimal luminal diameter, percent diameter stenosis, percent area stenosis and plaque burden were quantitatively analyzed. Two morphological patterns after balloon dilatation were classified by IVUS. Type I was defined as absence or partial tear of the plaque without disclosure of the media to lumen (22 lesions). Type II was defined as a split in the plaque or dissection of the vessel wall with disclosure of the media to the lumen (29 lesions). At 6 months follow-up, angiographic restenosis occurred in 17 of the 51 lesions (33%). Restenosis was significantly (p < 0.05) more likely to occur in type II (13/29: 45% incidence) than in type I (4/22: 18% incidence). The assessment of plaque morphology immediately after balloon dilatation and before stent implantation provides important therapeutic and prognostic implications.     

Intravascular ultrasound-guided percutaneous transluminal coronary angioplasty with provisional spot stenting for treatment of long coronary lesions.

OBJECTIVES: The purpose of this study was to evaluate the approach of intravascular ultrasound (IVUS)-guided percutaneous transluminal coronary angioplasty (PTCA) with spot stenting (SS) for the treatment of long coronary lesions. BACKGROUND: Treating long coronary lesions with balloon angioplasty results in suboptimal short- and long-term outcomes. Full lesion coverage with traditional stenting (TS) has been associated with a high restenosis rate. METHODS: We prospectively evaluated a consecutive series of 130 long lesions (>15 mm) in 101 patients treated with IVUS-guided PTCA and SS. The results were compared with those of TS in a matched group of patients. Coronary angioplasty was performed with a balloon to vessel ratio of 1:1, according to the IVUS media-to-media diameter of the vessel at the lesion site, to achieve prespecified IVUS criteria: lumen cross-sectional area (CSA) > or =5.5 mm(2) or > or =50% of the vessel CSA at the lesion site. The stents were implanted only in the vessel segment where the criteria were not met. RESULTS: In the SS group, stents were implanted in 67 of 130 lesions, and the mean stent length was shorter than that of lesions in the matched TS group (10.4 +/- 13 mm vs. 32.4 +/- 13 mm, p < 0.005). The 30-day major adverse cardiac event (MACE) rate was similar (5%) for both groups. Angiographic restenosis was 25% with IVUS-guided SS, as compared with 39% in the TS group (p < 0.05). Follow-up MACE and target lesion revascularization rates were lower in the SS group than in the TS group (22% vs. 38% [p < 0.05] and 19% vs. 34% [p < 0.05], respectively). CONCLUSIONS: Intravascular ultrasound-guided SS for the treatment of long coronary lesions is associated with good acute outcome. Angiographic restenosis and follow-up MACE rates were significantly lower than those with TS.     

Mechanisms of balloon angioplasty and directional coronary atherectomy as assessed by intracoronary ultrasound.

OBJECTIVE. This study was designed to use intracoronary ultrasound imaging to elucidate the physical effects of balloon angioplasty and directional coronary atherectomy in vivo in humans. BACKGROUND. The proposed mechanisms of coronary artery interventions such as balloon angioplasty and directional atherectomy are based on animal studies or pathologic findings and these data may not be applicable to living patients. Intracoronary ultrasound findings correlate highly with pathologic results and may allow in vivo assessment of the mechanisms of such interventions in humans. METHODS. Intracoronary ultrasound imaging was performed in 45 patients after a successful coronary intervention (balloon angioplasty in 30, directional coronary atherectomy in 15). Ultrasound images obtained at the treatment site and at an adjacent angiographically normal references site were analyzed quantitatively for minimal lumen diameter, cross-sectional lumen area, are enclosed by the internal elastic lamina, plaque area (internal elastic lamina area--lumen area) and percent area stenosis (plaque area/internal elastic lamina area). Qualitative analysis included assessment of presence of dissection, plaque composition and plaque topography. RESULTS. The results of the two procedures were similar with respect to minimal lumen diameter (angioplasty 2.6 +/- 0.5 vs. atherectomy 2.6 +/- 0.3 mm, p = NS), lumen area (0.07 +/- 0.03 vs. 0.07 +/- 0.02 cm2, p = NS) and percent area stenosis (59 +/- 14% vs. 51 +/- 21%, p = NS). However, after angioplasty, the internal elastic lamina area was significantly larger at the treated site than at the reference site (delta = +0.03 +/- 0.04 cm2, p = 0.01). There was no significant difference between the two sites after atherectomy (delta = -0.01 +/- 0.05 cm2, p = NS). In addition, dissection was seen significantly more often after balloon angioplasty than after atherectomy (50% vs. 7%, p less than 0.01). The results were similar when stratified for plaque composition and morphology. These data were confirmed in six additional patients who underwent ultrasound imaging before and after the intervention. CONCLUSIONS. Thus, the improvement in lumen dimensions after coronary balloon angioplasty is a result of both vessel stretch, demonstrated by a larger internal elastic lamina area at the treated site, and dissection. Both vessel stretch and dissection are uncommon after atherectomy, a finding consistent with plaque removal as the major mechanism for improved lumen area after this procedure.     

Intravascular ultrasound evaluation of the effect of rotational atherectomy in obstructive atherosclerotic coronary artery disease.

BACKGROUND. High-speed rotational atherectomy uses a diamond-coated, elliptical burr to abrade occlusive atherosclerosis, especially noncompliant calcified plaque. METHODS AND RESULTS. Intravascular ultrasound (IVUS) was used to analyze 28 patients after atherectomy. Arteries treated and imaged were left main (three), left anterior descending (12), left circumflex (five), right coronary (seven), and saphenous vein graft (one). Twenty patients had adjunct balloon angioplasty. Twenty-two (79%) target lesions were calcified; the intimal arc of calcium was 160 +/- 126 degrees (range, 0-360 degrees). After atherectomy, the intima-lumen interface was unusually distinct and circular. The lumen was larger than the largest burr used for both stand-alone (1.19 +/- 0.19-fold the largest burr size) and adjunct balloon procedures (1.30 +/- 0.15-fold the largest burr). Three-dimensional reconstruction of the ultrasound images showed a smooth lumen, especially in calcified plaque. Deviations from cylindrical geometry occurred only in areas of soft plaque or superficial tissue disruption of calcified plaque. Five patients were studied before and after rotational atherectomy. IVUS showed an increase in lumen size, a decrease in plaque-plus-media area and in arc of target lesion calcification, and no change in target lesion external elastic membrane cross-sectional area. CONCLUSIONS. Rotational atherectomy causes atheroablation with only moderate evidence of barotrauma in heavily calcified arteries, even after adjunct balloon angioplasty. The lumen is cylindrical, especially in areas of calcified plaque, and somewhat larger than the largest burr tip used.     

Mechanism of luminal gain with plaque excision in atherosclerotic coronary and peripheral arteries: assessment by histology and intravascular ultrasound

OBJECTIVES: Using intravascular ultrasound (IVUS) and histology, the purpose of this study was to evaluate the occurrence of arterial wall overstretch and Dotter effect following revascularization with a plaque excision (PE) catheter compared with balloon angioplasty. BACKGROUND: Previous studies have demonstrated the safety and feasibility of plaque excision for the treatment of de novo coronary and peripheral atherosclerotic disease. However, whether mechanical vessel dilatation related to catheter insertion contributes to gains in the final luminal diameter is uncertain. METHODS: Treatment with PE was assessed in both a porcine model (6 lesions treated with balloon angioplasty or PE) using histology and in humans with IVUS. In the latter part of the study, IVUS study was performed before and immediately following PE in 21 patients with either coronary artery disease (N = 13) or femoral artery disease (N = 8). Ultrasound measures in the femoral artery group were then compared with a control group of atherosclerotic lesions treated with conventional angioplasty that was matched according to lesion location and vessel diameter. RESULTS: Among individuals with coronary and peripheral arterial lesions treated with PE, the relative increases in luminal area secondary to reductions in plaque volume were 89% and 83%, respectively, with minimal increase in vessel diameter. In contrast, balloon angioplasty was associated with significantly greater vessel expansion and less plaque volume reduction. Vessel dissection also tended to occur less frequently and to a lesser extent with PE. CONCLUSIONS: Improvement in luminal dimensions using PE is principally due to a reduction in plaque volume rather than mechanical vessel expansion. The potential to increase luminal area while minimizing arterial dissection and barotrauma merits further clinical study with this method of revascularization.     

Preliminary experience at a Canadian centre with directional coronary atherectomy for complex lesions.

OBJECTIVE: To evaluate preliminary experience of directional coronary atherectomy for complex coronary artery lesions. DESIGN: Nonrandomized, sequential patients with coronary arterial lesions that were ostial, eccentric, bulky, recurrent or membranous. SETTING: Cardiac catheterization laboratory of a tertiary referral general hospital. PATIENTS: Twenty-three patients with angina pectoris refractory to medical therapy who were suitable candidates for coronary bypass surgery. INTERVENTIONS: Directional coronary atherectomy with associated balloon angioplasty, if required, to reduce lesion stenosis to less than 25%. MAIN RESULTS: Primary success was achieved in 29 of 33 lesions (88%) by atherectomy alone and in 31 of 33 lesions (94%) by additional use of balloon angioplasty. Atherectomy retrieved tissue in 30 of 33 attempts (91%). One patient suffered Q wave myocardial infarction; one had acute occlusion after atherectomy requiring emergency balloon angioplasty; and one required repair of a false aneurysm of the femoral artery. CONCLUSIONS: Directional coronary atherectomy is safe and efficacious for ostial, bulky and eccentric lesions not optimally suited to balloon angioplasty. Lesions which have tortuous segments immediately beyond, restricting movement of the stiff nose-cone, and which are membranous or bandlike, may not be indicated for directional coronary atherectomy.     

Do excimer laser angioplasty and rotational atherectomy facilitate balloon angioplasty? Implications for lesion-specific coronary intervention

Objectives. This study sought to determine whether adjunctive balloon angioplasty after rotational atherectomy and excimer laser angioplasty provides better lumen enlargement (“facilitated angioplasty”) than angioplasty alone.Background. Adjunctive angioplasty is often used immediately after atherectomy and laser angioplasty to further enlarge lumen dimensions, but it is not known whether this practice is superior to angioplasty alone.Methods. Balloon angioplasty was performed in 1,266 native coronary lesions alone (n = 541) or after extraction atherectomy (n = 277) rotational atherectomy (Rotablator) (n = 211) or excimer laser angioplasty (n = 237). Quantitative angiographic analysis included final lumen diameter, final diameter stenosis and efficiency of balloon-mediated lumen enlargement.Results. Compared with angioplasty alone (33 ± 12%) [mean ± SD]), final diameter stenosis was higher for adjunctive angioplasty after extraction atherectomy (37 ± 16%, p < 0.001) and excimer laser angioplasty (37 ± 16%, p < 0.001) and lower after rotational atherectomy (27 ± 15%, p < 0.001). However, there was significant undersizing of balloons after all three devices. To correct for differencs in balloon size, the efficiency index (final lumen diameter/balloon diameter ratio) was calculated and was higher for adjunctive angioplasty after the Rotablator (0.78 ± 0.14, p < 0.001) than after angioplasty alone (0.69 ± 0.12). The efficiency indexes suggested facilitated angioplasty after rotational atherectomy for ostial, eccentric, ulcerated and calcified lesions and lesions >20 mm long. Facilitated angioplasty was also observed after extraction atherectomy and excimer laser angioplasty for ostial lesions, but not for any other lesion subsets.Conclusions. Rotational atherectomy, extraction atherectomy and excimer laser angioplasty can facilitate the results of balloon angioplasty. However, the extent of facilitated angioplasty is dependent on the device and baseline lesion morphology, consistent with the need for lesion-specific coronary intervention.     

'Salvage atherectomy' for discrete arterial dissections resulting from balloon angioplasty.

OBJECTIVE: To review the outcome of attempted salvage atherectomy performed following failed balloon angioplasty at a single centre. DESIGN: Retrospective study. PATIENTS: All patients undergoing percutaneous directional atherectomy shortly after failed coronary or peripheral balloon angioplasty at St Paul's Hospital, Vancouver, British Columbia, are reported. INTERVENTIONS: Salvage atherectomy was performed in six patients following failed balloon angioplasty prior to hospital discharge. In each case, a discrete mural flap resulted in a compromised lumen and ischemia. MAIN RESULTS: Percutaneous directional atherectomy successfully recovered atheromatous intimal fragments with restoration of arterial patency in all patients. Media was identified in one specimen and adventitia in none. Perforation did not occur and there were no complications. One patient had documented restenosis and a second had a significant lesion at a more proximal site with a follow-up of four to 15 months (mean nine). Both patients underwent uncomplicated repeat balloon angioplasty without angiographical dissection. CONCLUSIONS: Salvage atherectomy has a limited--but still useful--role in the management of discrete, obstructive arterial dissection flaps complicating balloon angioplasty.     

Early and late clinical outcomes after rotational atherectomy with stenting versus rotational atherectomy with balloon angioplasty for complex coronary lesions

Limited data are available on the effect of rotational atherectomy plus stenting versus rotational atherectomy plus balloon angioplasty for complex coronary lesions. We compared the early and late clinical outcomes between rotational atherectomy plus stenting (158 patients, 171 lesions) and rotational atherectomy plus balloon angioplasty (165 patients, 186 lesions) for complex lesions. Baseline characteristics were similar between the two groups. The procedural success rate was similar between the 2 groups (94% in rotational atherectomy plus stenting versus 96% in rotational atherectomy plus balloon angioplasty; p = 0.54). There were no significant differences in the in-hospital complications between the 2 groups. During mean follow-up of 40.4 +/- 20.2 months, fourteen patients died: 6 in rotational atherectomy plus stenting and 8 in rotational atherectomy plus balloon angioplasty. Target lesion revascularization was similar between the 2 groups (20% in rotational atherectomy plus stenting versus 24% in rotational atherectomy plus balloon angioplasty; p = 0.46). Three-year event (death, nonfatal myocardial infarction and target lesion revascularization)-free survival rate was 79 +/- 4% in the rotational atherectomy plus stenting group and 75 +/- 3% in the rotational atherectomy plus balloon angioplasty group (p = 0.44). In conclusion, rotational atherectomy followed by stenting or balloon angioplasty is associated with favorable long-term outcomes. Compared with rotational atherectomy plus balloon angioplasty, routine stenting after rotational atherectomy does not provide additional benefits in the clinical outcomes in complex coronary lesions.     

Excimer Laser Atherectomy in Percutaneous Coronary Intervention: A Contemporary Review

Excimer laser coronary atherectomy (ELCA) during percutaneous coronary intervention (PCI) has been in use for more than twenty years. While early experiences were not favorable over balloon angioplasty alone, with improvement in operator technique, patient selection and technology, ELCA has established its own niche in contemporary PCI as a safe and effective atherectomy strategy. With growing experience in complex coronary interventions worldwide, ELCA has become one of the essential atherectomy tools offering unique advantages over other atherectomy devices. In the modern era, ELCA is commonly used for patients with in-stent restenosis, stent under expansion, balloon uncrossable lesions and chronic total occlusions. Technical success rates are reported to be >80% in most situations while procedural complication rates such as vessel dissection and perforation among others are reported to average 9% over the past 25 years with improvement over time. In this review, we provide a comprehensive systematic review of the ELCA system, its practical use, indications, and procedural techniques in the contemporary PCI era.     

Intravascular ultrasound detected calcification of coronary lesions as a predictor of dissections after balloon angioplasty

Dissection after balloon angioplasty of coronary arteries may give rise to an unfavourable early outcome. Compared with coronary angiography, intravascular ultrasound (IVUS) allows more detailed characterisation of dissections. We investigated the incidence and the type of dissections after balloon angioplasty in calcified coronary lesions.IVUS was performed in 43 patients with 48 lesions before and after percutaneous balloon angioplasty. Significant calcification was defined as an are of more than 90° with typical acoustic shadowing. Dissections were classified as type A when the media was not involved by the dissection and as type B when media involvement had occured.In the group with significant calcification dissection was observed in 79 % of the cases vs. 38 % in the control group (p<0.03). Type B dissection was present in 71 % of the dissections in the calcified lesions vs. 15 % in the control group (p<0.02). The balloon diameter and the ratio of balloon area to vessel area was not different in both groups but the required pressure for the first complete balloon inflation was significantly greater in the group with calcified lesions (9.46±3.6 atm vs. 6.65±2.6 atm; p<0.001).Thus balloon angioplasty in calcified coronary lesions is more likely to lead to dissection which frequently involve the media.     

High speed rotational coronary atherectomy for patients with diffuse coronary artery disease

High speed rotational coronary atherectomy was undertaken using the Rotablator in 42 patients who were suboptimal candidates for balloon angioplasty. Most patients (71%) had diffuse coronary artery disease, defined as a stenosis greater than 1 cm in length. Previous restenosis after balloon angioplasty was present in 21% and 10% had an ostial lesion. Adjunctive balloon angioplasty was not used to reduce residual stenosis after atherectomy. The procedure was successful in 76% of patients. Procedural success was achieved in 92% of patients with a lesion less than or equal to 1 cm in length, but in only 70% of patients with a lesion greater than 1 cm in length (p less than 0.01). One patient sustained abrupt closure of the target vessel, resulting in emergency bypass surgery and death. Small non-Q wave myocardial infarction occurred in eight patients (19%) and was associated with a longer lesion. The mean peak creatine kinase value in patients with non-Q wave myocardial infarction was 683 U/liter. Transient regional wall motion abnormalities were noted on the postatherectomy left ventricular angiogram in four of the eight patients with non-Q wave myocardial infarction. Follow-up angiography (at a mean interval of 6.2 +/- 2.6 months) was performed in 91% of patients and revealed restenosis (greater than 50% narrowing) in 59% The resistance rate was 22% for short lesions (less than or equal to 1 cm) and 75% for long lesions (greater than 1 cm) (p less than 0.05). In this study, the results of high speed rotational coronary atherectomy were strongly influenced by lesion length.(ABSTRACT TRUNCATED AT 250 WORDS)     

The decrease of plaque volume during percutaneous coronary intervention has a negative impact on coronary flow in acute myocardial infarction: a major role of percutaneous coronary intervention-induced embolization

OBJECTIVES: The aim of this study was to evaluate how decreased plaque volume during percutaneous coronary intervention (PCI) affects coronary flow in patients with acute myocardial infarction (AMI). BACKGROUND: Coronary flow after reperfusion therapy is a major determinant of clinical outcomes in patients with AMI. However, little is still known about the changes in coronary flow that appear after PCI in response to the decreased plaque during the procedure. METHODS: The study group comprised 60 patients with AMI who underwent pre- and post-PCI intravascular ultrasound (IVUS). Qualitative and quantitative analyses were performed on all IVUS procedures. External elastic membrane volume (EEMV), lumen volume (LV), and plaque volume (PV) were measured every 1.0 mm to include the lesion and reference segments 3.0 mm proximal and distal to the lesion. The difference between pre- and post-PCI PV was defined as the index of the decrease in plaque volume (DeltaPV). The corrected TIMI frame count (CTFC) was used to evaluate coronary flow after PCI. RESULTS: Plaque volume was decreased at post-PCI IVUS in all 60 patients. Inadequate reflow (CTFC >40) was observed in 13 patients (21.7%). The decrease in PV was significantly larger in patients with inadequate reflow than in those with reflow (49.4 +/- 18.9 vs. 31.7 +/- 15.5 mm(3), p = 0.0010). Also, DeltaPV was significantly correlated with CTFC after PCI (r = 0.415, p = 0.0012). CONCLUSIONS: The decrease in PV during PCI has a negative impact on coronary flow after PCI in patients with AMI. Embolization induced by PCI may occur in all patients with AMI.     

Mechanisms and immediate and long-term results of adjunct directional coronary atherectomy after rotational atherectomy

Objectives.The purpose of this study was to confirm the mechanisms and the immediate and long-term results of rotational atherectomy and adjunct directional coronaryatherectomy.Background.Rotational atherectomy is best suited for treating calcific stenoses, but the ability of rotational atherectomy alone to optimize lumen dimensions in large vessels is limited; this is only partly improved by adjunct balloon angioplasty.Methods.We treated 165 lesions in 163 patients by use of rotational atherectomy and adjunct directional coronary atherectomy. Quantitative angiography and intravascular ultrasond were used for lesion analysis. A matched comparison with 208 lesions treated with rotational atherectomy and adjunct coronary angioplasty was performed. Patients were then followed up for at least 9 months, and target-lesion revascularization was assessed.Results.In the 61 lesions imaged sequentially, lumen area increased from 1.7 ± 0.8 (mean ± 1 SD) to 3.9 ± 1.1 mm²after rotational atherectomy, owing to a decrease in plaque plus media area from 16.8 ± 5.0 to 15.2 ± 5.2 mm²(both p < 0.0001). After adjunct directional coronary atherectomy, lumen area increased even more to 6.7 ± 2.0 mm²(vs. 5.1 ± 1.4 mm²after adjunct coronary angioplasty, p < 0.0001) as a result of both vessel expansion (18.8 ± 5.3 to 20.8 ± 5.7 mm²) and additional plaque removal (to 14.1 ± 5.0 mm², all p < 0.0001). The total arcs of calcium decreased from 207 ± 107° to 166 ± 93° after rotational atherectomy and to 145 ± 87° after directional coronary atherectomy.Overall, procedural success was 96%, and final diameter stenosis was 15 ± 17%. Target-lesion revascularization was 23%. The only independent predictor of target-lesion revascularization was a larger overall atherectomy index (84% vs. 59%, p = 0.048).Conclusions.There is a synergistic relationship between rotational atherectomy and directional coronary atherectomy in the treatment of calcific lesions. The immediate results show a high procedural success—lumen dimensions were larger and late target-lesion revascularization was lower in lesions treated with rotational atherectomy and directional coronary atherectomy than in those treated with rotational atherectomy and adjunct balloon angioplasty.     

Quantitative angiography after directional coronary atherectomy.

OBJECTIVE--To assess by quantitative analysis the immediate angiographic results of directional coronary atherectomy. To compare the effects of successful atherectomy with those of successful balloon dilatation in a series of patients with matched lesions. DESIGN--Case series. SETTING--Tertiary referral centre. PATIENTS--62 patients in whom directional coronary atherectomy was attempted between 7 September 1989 and 31 December 1990. INTERVENTIONS--Directional coronary atherectomy. MAIN OUTCOME MEASURES--Increase in minimal luminal diameter of coronary artery segment. RESULTS--Angiographic success on the basis of intention to treat was obtained in 54 patients (87%). In four patients the lesion could not be crossed by the atherectomy device; all four had an uneventful conventional balloon angioplasty. Four of the 58 patients who underwent atherectomy were subsequently referred for coronary bypass surgery because of failure or complications; three of them sustained a transmural infarction. In the successful cases, coronary atherectomy resulted in an increase in the minimal luminal diameter from 1.1 mm to 2.5 mm with a concomitant decrease of the diameter stenosis from 62% to 22%. In the subset of 37 patients in which the changes induced were compared with conventional balloon angioplasty atherectomy increased the minimal luminal diameter more than balloon angioplasty (1.6 v 0.8 mm; p less than 0.0001). Conventional histology showed media or adventitia in 26% of the atherectomy specimens. In hospital complications occurred in six patients who had undergone a successful procedure: two transmural infarctions, two subendocardial infarctions, one transient ischaemia attack, and one death due to delayed rupture of the atherectomised vessel. All patients were clinically evaluated at one and six months. One patient had persisting angina (New York Heart Association class II), one patient sustained a myocardial infarction, one patient underwent a percutaneous transluminal coronary angioplasty for early restenosis, and one patient underwent coronary bypass surgery because of a coronary aneurysm formation. At six months 80% (36/47) of the patients were symptom free. CONCLUSIONS--Coronary atherectomy achieved a better immediate angiographic result than balloon angioplasty; however, in view of the complication rate in this preliminary series, which may be related to a learning curve, a randomised study is needed to show whether this procedure is as safe as a conventional balloon angioplasty.     

Quantitative angiography after directional coronary atherectomy

OBJECTIVE--To assess by quantitative analysis the immediate angiographic results of directional coronary atherectomy. To compare the effects of successful atherectomy with those of successful balloon dilatation in a series of patients with matched lesions. DESIGN--Case series. SETTING--Tertiary referral centre. PATIENTS--62 patients in whom directional coronary atherectomy was attempted between 7 September 1989 and 31 December 1990. INTERVENTIONS--Directional coronary atherectomy. MAIN OUTCOME MEASURES--Increase in minimal luminal diameter of coronary artery segment. RESULTS--Angiographic success on the basis of intention to treat was obtained in 54 patients (87%). In four patients the lesion could not be crossed by the atherectomy device; all four had an uneventful conventional balloon angioplasty. Four of the 58 patients who underwent atherectomy were subsequently referred for coronary bypass surgery because of failure or complications; three of them sustained a transmural infarction. In the successful cases, coronary atherectomy resulted in an increase in the minimal luminal diameter from 1.1 mm to 2.5 mm with a concomitant decrease of the diameter stenosis from 62% to 22%. In the subset of 37 patients in which the changes induced were compared with conventional balloon angioplasty atherectomy increased the minimal luminal diameter more than balloon angioplasty (1.6 v 0.8 mm; p less than 0.0001). Conventional histology showed media or adventitia in 26% of the atherectomy specimens. In hospital complications occurred in six patients who had undergone a successful procedure: two transmural infarctions, two subendocardial infarctions, one transient ischaemia attack, and one death due to delayed rupture of the atherectomised vessel. All patients were clinically evaluated at one and six months. One patient had persisting angina (New York Heart Association class II), one patient sustained a myocardial infarction, one patient underwent a percutaneous transluminal coronary angioplasty for early restenosis, and one patient underwent coronary bypass surgery because of a coronary aneurysm formation. At six months 80% (36/47) of the patients were symptom free. CONCLUSIONS--Coronary atherectomy achieved a better immediate angiographic result than balloon angioplasty; however, in view of the complication rate in this preliminary series, which may be related to a learning curve, a randomised study is needed to show whether this procedure is as safe as a conventional balloon angioplasty.     

血管内超声的冠状动脉腔内成形术的机制研究

目的应用血管内超声的方法研究病人经皮冠状动脉(冠脉)腔内成形术(PTCA)前后冠脉内的粥样斑块和血管壁的变化,进一步明确PTCA的机制。方法择期行PTCA的病人50例,共68支血管于球囊扩张前后行冠脉内超声(ICUS)检查。记录病变部位粥样斑块的特性,最小管腔面积,弹力内膜面积和斑块面积。结果PTCA球囊扩张前后病变部位的内弹力膜面积(IELA)分别为(6.67±1.45)mm2和(8.14±1.13)mm2,术后有明显的扩大(P＜0.05)。脂质斑块,纤维斑块,钙化斑块,混合斑块各组PTCA手术前后IELA之差(ΔIELA)分别为1.84,1.52,0.40,1.23mm2,钙化斑块球囊扩张前后内弹力膜面积无明显扩大,P＜0.05。斑块的撕裂程度及管壁变化根据Honye分类法记录A型10例,B型20例,C型16例,D型12例,E1型5例,E2型5例。68个病变中有58个（85%）病变出现不同程度的斑块撕裂。12个D型撕裂中有11个是钙化的斑块,1个是混合斑块。结论粥样斑块的撕裂和管壁的牵伸在冠脉球囊扩张术的管腔增大方面同时起关键作用,较硬的斑块如钙化的斑块球囊扩张时易出现大的夹层,而血管牵伸的程度较差,用旋磨或旋切的方法处理可能会得到更好的结果。     

旋磨术联合切割球囊成形术治疗冠状动脉重度钙化病变

目的血管内超声评价旋磨术联合切割球囊成形术治疗冠状动脉重度钙化病变的安全性及有效性。方法收集冠状动脉造影及血管内超声检查确认至少1处病变为高度钙化,并行旋磨术处理的冠心病患者80例,根据是否使用切割球囊分为单纯旋磨组34例和旋磨联合切割组46例。患者在支架置入前及置入后均行血管内超声检查,评价支架置入效果。结果单纯旋磨组与旋磨联合切割组最大钙化弧度分别为(215.88±21.81)°vs(226.55±21.59)°,钙化长度比为(0.72±0.06)vs(0.78±0.05),支架置入前最小管腔面积为(2.52±0.07)mm2 vs(2.46±0.09)mm2,2组比较差异无统计学意义(P>0.05)。支架置入后,旋磨联合切割组最小支架面积(6.12±0.37)mm2和即刻管腔获得面积(3.66±0.34)mm2,单纯旋磨组分别为(5.42±0.24)mm2和(2.90±0.24)mm2,2组比较差异有统计学意义(P=0.016)。2组术中并发症的发生比例比较,差异无统计学意义(P>0.05)。结论在冠状动脉重度钙化病变中,使用旋磨术联合切割球囊成形术可以获得更好的支架置入后效果。