Coronary angioplasty with a rotary atherotome]

Several new coronary dilatation systems, including those using laser energy, atherectomy devices and stent implantation, are being developed as alternative or complementary procedures to coronary artery balloon angioplasty. We report our initial experience performing coronary angioplasty with a new rotational atherectomy device, the transluminal extraction catheter, which simultaneously cut and aspirate fragments from the atherosclerotic plaque. The components of the whole system are a special guidewire to cross the stenosis, the atherectomy catheter and the conduction-control unit. This unit, connected when the atherectomy catheter is positioned across the lesion, produces rotation of the conical bladder located in the catheter distal tip and simultaneous aspiration of residual particles. The procedure was performed in 11 patients in whom 13 lesions were dilated. All patients were male (mean age 55 +/- 23 years, range 45-77). The reason for the angioplasty was stable angina in 2 patients and unstable angina in the remaining seven. Initial success (residual stenosis less than 50% of vessel diameter) was obtained in 10 of 13 lesions. In two, conventional balloon angioplasty was required to improve atherectomy result. The only unsuccessful procedure was in a proximal right coronary artery venous graft, in which a large dissection occurred. Patient had angina but no myocardial infarction. Pathologic examination of aspirated material revealed fibrous tissue in 12 cases and cholesterol crystals in four. We conclude, with the limitation of a preliminary study, that rotational atherectomy with the transluminal extraction catheter is a useful procedure to relief coronary stenosis of the coronary arteries.     

Efficacy of a new angioplasty catheter for severely narrowed coronary lesions

Conventional over the wire dilation catheters may be unsuccessful in crossing coronary lesions that are severely narrowed. Hence, a new, extremely low profile coronary angioplasty catheter specifically designed to dilate such lesions was investigated. The catheter features a 2.0, 2.5 or 3.0 mm (inflated diameter) balloon mounted on a guide wire. The deflated profile of the 2.0 mm balloon measures 0.020 +/- 0.001 in. (0.51 +/- 0.03 mm). The catheter can be used in conjunction with 7F angiographic or 8F guide catheters. The catheter was used in 61 patients, aged 43 to 86 years, with predominantly Canadian Cardiovascular Society class III-IV angina. Dilation was attempted in 77 lesions. Lesion length averaged 5.7 +/- 3.1 mm (mean +/- 1 SD), minimal diameter 0.51 +/- 0.25 mm and internal vessel diameter 2.27 +/- 0.43 mm. Sixty lesions (78%) were successfully dilated to less than 50% residual stenosis with this catheter alone; nine lesions were further dilated with a larger balloon catheter. The new catheter was unable to cross 13 lesions (17%); only 2 of these lesions were subsequently crossed with a conventional over the wire system. On the other hand, the catheter was used after failure of conventional dilating catheters in 21 lesions and was successful in 16. The new catheter was particularly valuable for distal lesions and those demonstrating 90 to 99% diameter reduction. For all lesions crossed, stenosis decreased from 76 +/- 11 to 29 +/- 12% after 2.9 +/- 2.7 inflations and peak inflation pressure of 8.0 +/- 2.9 bar. Complications were rare; coronary occlusion occurred in two lesions (3%) and dissection in three lesions (4%).(ABSTRACT TRUNCATED AT 250 WORDS)     

A new catheter system for coronary angioplasty

A new catheter system has been designed for percutaneous transluminal coronary angioplasty. An independently movable, flexible-tipped guide wire within the balloon dilation catheter facilitates selection of the involved vessel. This guide wire can be passed slowly and carefully beyond the coronary stenosis, permitting safe advancement of the balloon catheter. After testing in animal and cadaver hearts, this system was used in 53 patients (56 stenoses) with single vessel coronary artery disease, with an overall primary success rate of 64 percent. In the last 41 of these 56 cases, use of a balloon catheter with a smaller deflated diameter increased the success rate to 73 percent. In patients with lesions of the left anterior descending coronary artery, the success rate was 89 percent. Three (6 percent) of the 53 patients had complications during coronary arterial dilation that necessitated emergency coronary arterial bypass graft surgery. There were no procedure-related or late cardiac deaths. During the mean follow-up period of 8 months (range 1 to 21), there were one late death (of noncardiac causes) and no late myocardial infarctions. Clinical status was persistently improved in 31 of the 36 patients who had successful dilation. The remaining five patients experienced restenosis at the angioplasty site and return of angina pectoris within 3 months of dilation. Two of these patients had repeat coronary angioplasty with restoration of asymptomatic status, and three had elective coronary bypass graft surgery.     

Percutaneous peripheral laser angioplasty: initial clinical results

Laser angioplasty has developed as a new method for the treatment of peripheral arterial occlusive disease. In 19 patients with high grade stenoses or obstructions of the superficial femoral, popliteal or posterior tibial arteries (Fontaine stage IIa-IV) percutaneous transluminal laser angioplasty was performed using a novel laser catheter system. The laser catheter itself is made of polyethylene. Its distal tip is formed ovally and marked X-ray densely. A silica fiber (core diameter 0.6 mm) for delivering the laser energy is inserted into the laser catheter. Through a sheath with hemostatic valve, laser catheter and silica fiber are introduced into the artery and then advanced to the stenosis over a guide wire. During laser angioplasty, laser catheter and silica fiber are rotated around the guide wire. We use a cw-Nd: YAG laser with a wavelength of 1064 nm. The mean degree of stenosis decreased from 92 +/- 12% before to 31 +/- 19% after laser angioplasty. By conventional balloon angioplasty a further reduction of the degree of stenosis down to 15 +/- 20% was achieved. The mean systolic Doppler ankle-arm pressure ratio improved from 0.56 +/- 0.25 before laser angioplasty to 0.89 +/- 0.24 after combined laser and balloon angioplasty. In seven patients, clinically non-significant distal embolization occurred. In no patient there was a perforation of the arterial wall. Up to now, digital subtraction angiography 3 months after laser angioplasty has been performed in five patients and showed patency of all lesions. The mean systolic Doppler ankle-arm pressure ratio was 0.84 +/- 0.20.     

The use of an exchange guide wire in coronary angioplasty

Of 84 consecutive patients referred for coronary angioplasty, an exchange length (260 cm) guide wire was used in 17 (20%) to allow serial passage of different sized dilatation catheters. Exchanges were performed for the following reasons: 1) inability to cross the stenotic segment with a full-sized dilatation catheter, with exchange for a smaller catheter to permit initial dilatation followed by a second exchange to reintroduce the full-sized balloon catheter; 2) premeditated initial use of a low-profile balloon catheter in severe stenosis, with subsequent exchange to a full-sized balloon catheter; 3) inability to achieve a satisfactory reduction of the transstenotic gradient or angiographic stenosis with the initial dilation catheter, requiring subsequent passage of a larger balloon catheter into the partially dilated segment. Eighteen of 19 attempted exchanges and 18 of 19 angioplasty procedures were completed successfully. The use of exchange guide wires permits multiple recrossings of a dilated segment, allows safe serial passage of different sized balloon catheters, and obviates the need for renegotiating difficult proximal coronary anatomy. The exchange guide wire techique can be applied safely and effectively to coronary angioplasty and provides an additional option in the successful completion of movable guide wire angioplasty procedures.     

Early experience with low speed rotational angioplasty.

OBJECTIVE--Preliminary assessment of the efficacy and safety of the low speed rotational angioplasty catheter system (ROTACS). DESIGN--Open prospective trial. SETTING--Department of cardiology in a teaching hospital. PATIENTS--Eleven patients (10 with chronic stable angina and one with acute coronary occlusion after conventional angioplasty) in whom a coronary angiogram showed occlusion or critical stenosis of the coronary artery (right in seven patients, circumflex in two, and left anterior descending in two). The nature or severity of the lesion ruled out conventional coronary angioplasty. INTERVENTIONS--An attempt was made to cross the lesion with a rotating guide wire with a blunt swelling at its tip. Where necessary progress was assessed by simultaneous injection of contrast into both main coronary arteries. MAIN OUTCOME MEASURES--Progress of the ROTACS through the lesion that allowed a guide wire to pass into the distal vessel was regarded as a device specific success. When a guide wire crossed the lesion aided only by the support of the ROTACS without the use of rotation this was counted as a success that was not device specific. Failure to cross the lesion and any associated complications were noted. RESULTS--The ROTACS crossed only two of the 10 chronic lesions (20% device specific success rate); however, the support it provided enabled a guide wire to cross a further two lesions and allowed subsequent successful angioplasty in four of the 10 patients. One of these four patients presented after five months with recurrent angina requiring bypass grafting. The other three were symptom free at follow up seven months after the procedure. In the one patient with acute coronary occlusion the ROTACS was advanced over the guide wire to allow passage of an angioplasty balloon where this had previously proved impossible. An excellent final result was obtained and this patient remains symptom free. Three of the six patients in whom the ROTACS was unsuccessful had coronary artery dissection without sequelae. Three patients required subsequent elective coronary bypass grafting for control of symptoms while the other three remain well on medical treatment. CONCLUSIONS--The ROTACS may extend the range of patients with coronary artery occlusion or critical stenosis who can be treated non-surgically. The low device specific success rate (20%) achieved in this study indicates that it should be compared with other simpler mechanical devices that may be just as effective.     

One hundred and thirteen attempts at directional coronary atherectomy: the early and combined experience of two European centres using quantitative angiography to assess their results.

Directional coronary atherectomy has been introduced as an alternative to conventional balloon angioplasty when treating coronary artery stenoses with complex lesion morphology. To determine the immediate efficacy of coronary atherectomy in patients with such lesions, the first 113 attempts at directional atherectomy in two centres using quantitative angiography were reviewed in 105 patients. The lesions were classified as complex stenosis since 95% had a symmetry index less than 1.0, a length of 6.83 +/- 2.55 mm on average and an area of plaque of 9.77 +/- 6.69 mm2. Procedural success defined as a residual stenosis less than or equal to 50% after tissue retrieval was obtained in 90 (85.7%) of 105 patients. The primary angioplastic success rate, combining atherectomy and balloon angioplasty in case of failed attempt of atherectomy was 95.2%. Coronary atherectomy was unsuccessful in five patients; three were referred for emergency coronary artery bypass grafting. Major complications (death, emergency surgery and transmural infarction) were encountered in 5.7% of the patients. Assessed by quantitative coronary analysis, a residual minimal luminal diameter of 2.42 +/- 0.52 mm and a diameter stenosis of 26 +/- 12% were obtained immediately after directional coronary atherectomy. We conclude that directional coronary atherectomy is particularly suitable for the treatment of stenosis with complex lesion morphology and is associated with acceptable complication rates. Randomized trials comparing atherectomy with balloon angioplasty are warranted to clarify the role of atherectomy in the treatment of lesions in the proximal part of the three major epicardial coronary arteries.     

Percutaneous transluminal coronary angioplasty in a patient with Kawasaki disease. A case report of an unsuccessful angioplasty.

A 13-year-old boy with severe coronary stenosis due to Kawasaki disease underwent percutaneous transluminal coronary angioplasty (PTCA). The guide wire and the balloon catheter easily passed through the stenosis in the left anterior descending artery. However, effective dilatation could not be achieved even when the balloon size was increased to 2.5 mm in diameter. We discontinued further inflation of the balloon because serious resistance was encountered on withdrawal of the balloon catheter. In patients with Kawasaki disease, the value of PTCA as a treatment for coronary stenosis is questionable.     

Effectiveness of rotational atherectomy of right coronary artery ostial stenosis

Balloon angioplasty and stenting of right coronary ostial stenosis may frequently be impeded by lesion calcification, whereas rotational atherectomy, which ablates calcified plaque, should treat these lesions effectively. Accordingly, we evaluated procedural success and longterm clinical outcome of rotational atherectomy of right coronary ostial stenosis. Procedural data were obtained from a comprehensive interventional registry and follow-up information was obtained by chart review and patient enquiry. All patients who developed recurrent angina underwent angiographic restudy. During a 5-year interval, 119 patients underwent rotational atherectomy of right coronary ostial stenosis. Multilesion interventions were performed in 55% of patients. Ostial lesions were 3.73+/-3.69 mm in length (mean +/- SD), and 57.1% were significantly calcified. Reference vessel diameter was 3.42+/-0.56 mm. Maximum burr:artery ratio was 0.64+/-0.1 with adjunct balloon angioplasty in 89.1% and adjunct stenting in 9.2%. Procedural success (<50% residual stenosis without major complication) was 97.5%, with 1.7% uncomplicated failure and 0.8% Q-wave infarction. Maximum residual stenosis was 15+/-17%. During 6-month follow-up, available in 94% of patients, 82.7% remained angina-free, 10.9% developed recurrent angina due to right coronary ostial restenosis, and 6.4% developed recurrent angina due to another lesion. Two years after intervention, target lesion revascularization rate was 16%. Predictors of symptomatic angiographic restenosis were dissection >10 mm, final minimal luminal diameter <2.5 mm, lesion length >10 mm, restenotic lesion, and diabetes. We conclude that rotational atherectomy of right coronary ostial stenosis results in excellent acute procedural success and in low incidence of clinical recurrence, with a high proportion of patients remaining angina-free 2 years after intervention.     

Mechanical thrombectomy: a comparison of two rotational devices and balloon angioplasty in subacute canine femoral thrombosis

In this study, two prototype rotational devices were compared to balloon angioplasty in a canine model of subacute arterial thrombosis. Radiographic 2- to 8-day-old total thrombotic occlusions were produced in 30 canine femoral arteries. A high-speed rotating device with a cutting tip was used in 18 arteries. Successful opening occurred in every case, with a residual percent diameter stenosis at 45 +/- 25%. Vessel perforation was seen in 6 of the 18 arteries. A noncutting rotational thrombectomy catheter was used in six arteries. Radiographic patency was established in two of six (residual stenosis 86 +/- 28%), with one perforation with the use of the noncutting thrombectomy catheter. Balloon angioplasty reestablished radiographic patency in three of six arteries (residual stenosis 77 +/- 2%). No perforations were seen with balloon dilation, but radiographic distal emboli were always observed. No radiographic emboli were observed with either of the rotational devices. We conclude that subacute arterial thromboses are easily opened with an abrasive-tipped rotating angioplasty device. Although perforations are relatively common with this prototype equipment, design changes may produce a clinically useful angioplasty device.     

Recanalization of chronic total coronary arterial occlusions by percutaneous excimer-laser and laser-assisted angioplasty

A low primary success and high restenosis rate after recanalization of chronic total occlusions by conventional coronary angioplasty have encouraged the application of new interventional techniques like excimer-laser angioplasty. In 39 patients with a coronary occlusion for 1 to 12 months, recanalization was attempted by laser angioplasty through a multifiber-catheter coupled to a pulsed XeCl excimer laser. After successful passage of the occlusion by a standard guidewire in 27 patients (69%), the laser catheter was advanced over the central guidewire and crossed the occlusion in 25 patients (64%). In 2 patients with unsuccessful passage of the laser catheter, the subsequent attempt with a low profile balloon catheter also failed. In 19 of the 25 patients with successful laser recanalization, the residual stenosis exceeded 50% and was therefore followed by additional balloon angioplasty. The average residual stenosis after laser was 61 +/- 17% of the vessel diameter, and after balloon angioplasty 28 +/- 9% (n = 19), whereas after laser angioplasty alone it was 38 +/- 5% (n = 6). No complications associated with the laser application were observed. Angiographic control after 24 hours showed a reocclusion of 2 (8%) recanalized vessels. In this pilot study, laser angioplasty proved to be a safe and feasible method for the treatment of chronic total coronary occlusions. Because it was necessary to guide the catheter by a central wire, the primary success was limited by a successful passage of the wire of the occlusion. The rate of stand-alone laser angioplasty has to be increased by future improvements of the technique to enable a comparative evaluation of this method with conventional angioplasty.     

Laser balloon angioplasty: clinical, angiographic and histologic results

Laser balloon angioplasty combines conventional coronary angioplasty with laser energy to transiently heat vascular tissue. Laser balloon angioplasty, was performed in 21 patients (aged 56 +/- 13 years), including 10 patients treated urgently after acute failure of conventional angioplasty and 11 patients treated with elective laser balloon angioplasty. Immediately after conventional angioplasty, laser doses (1 to 10 doses of 205 to 380 J each) were delivered during inflation of the laser balloon to a pressure of 4 atm. Seven (70%) of 10 patients with acute failure of conventional angioplasty were successfully treated with laser balloon angioplasty, but 3 (30%) were unsuccessfully treated with the laser procedure and required emergency coronary artery bypass surgery. In all three failures, the 3 mm laser balloon angioplasty catheter was not the optimal size for the vessel. In the 11 patients treated with elective laser balloon angioplasty (reference diameter 2.94 +/- 0.22 mm), the minimal luminal diameter increased from 0.45 +/- 0.25 to 1.85 +/- 0.46 mm after conventional angioplasty and to 2.44 +/- 0.29 mm after laser balloon angioplasty (p less than 0.001). This corresponded to a decrease in diameter stenosis from 84 +/- 9% before to 35 +/- 16% after conventional angioplasty and to 15 +/- 10% after laser balloon angioplasty (p less than 0.001). There were no instances of myocardial infarction, emergency coronary artery bypass surgery or death and no acute complications related to delivery of laser energy in this group. Follow-up coronary angiography was performed 5.5 +/- 1.1 months after laser balloon angioplasty in 18 patients discharged from the hospital after a successful procedure. Ten patients (56%) had angiographic restenosis, defined as recurrent diameter stenosis greater than 50%. Six patients were subsequently treated by directional coronary atherectomy, which revealed intimal proliferation indistinguishable from that in patients with restenosis after conventional angioplasty. In conclusion, laser balloon angioplasty may be effective in sealing severe coronary dissections and reversing abrupt closure associated with failed conventional angioplasty. After uncomplicated conventional angioplasty, laser balloon angioplasty improves immediate luminal dimensions, but restenosis appears to be mediated by intimal hyperplasia, similar to that seen after conventional angioplasty.     

Multicenter study of percutaneous transluminal angioplasty for right coronary artery ostial stenosis

Over a 5 year period at three centers, 53 patients underwent percutaneous transluminal angioplasty of a right coronary artery ostial stenosis. The procedure was successful in 42 patients (79%) and unsuccessful in 11, of whom 5 (9.4%) required emergency coronary artery bypass grafting because of abrupt closure. The right coronary ostial lesion had distinctive technical requirements to achieve success, including high pressure balloon inflation (10 +/- 4 atm) and the need for unconventional right coronary guide catheters. Technical factors that account for increased difficulty in these patients include: problems with guide catheter impaction and ostial trauma; inability to inflate the balloon with adequate guide catheter support; and need for increased intracoronary manipulation. The stenoses were quite discrete (4 +/- 5 mm) and calcified in the majority (40) of the 53 patients. Long-term follow-up (mean 12.5 months, range 4 to 60) of these patients demonstrated clinical recurrence of angina in 20 patients (48%) and angiographically proved restenosis in 16 (38%). Repeat coronary angioplasty was successful in three of six patients for relief of symptoms for over 6 months. In conclusion, angioplasty of the right coronary ostial lesion compared with nonostial dilation leads to a suboptimal early success rate; an apparent high risk of emergency bypass surgery; and a high restenosis rate. Careful assessment of the patient with this lesion and improved technology appear to be warranted.     

Percutaneous excimer laser coronary angioplasty

To determine the efficacy of percutaneous excimer laser coronary angioplasty as an adjunct or alternative to conventional balloon angioplasty, 55 patients were studied in a multicenter trial. These patients underwent the procedure using a modification of conventional balloon angioplasty technique. A first-generation, 1.6-mm diameter catheter constructed of 12 individual silica fibers concentrically arranged around a guidewire lumen was used. Catheter tip energy density varied from 35 to 50 mJ/mm2. The mean number of pulses delivered at 20 Hz was 1,272 +/- 1,345. Acute success was defined as a greater than or equal to 20% increase in stenotic diameter and a lumen of greater than or equal to 1 mm in diameter after laser treatment. Acute success was achieved in 46 of 55 (84%) patients. Adjunctive balloon angioplasty was performed on 41 patients (75%). The percent diameter stenosis as determined by quantitative angiography decreased from a baseline of 83 +/- 14 to 49 +/- 11% after laser treatment and to 38 +/- 12% in patients undergoing adjunctive balloon angioplasty. The mean minimal stenotic diameter increased from a baseline of 0.5 +/- 0.4 to 1.6 +/- 0.5 mm after laser treatment and to 2.1 +/- 0.5 mm after balloon angioplasty. There were no deaths and no vascular perforations. One patient (1.8%) required emergency coronary bypass surgery. These data suggest that excimer laser energy delivered percutaneously by specially constructed catheters can safely ablate atheroma and reduce coronary stenoses.     

Percutaneous coronary mid-infra-red laser angioplasty.

A pilot study was performed to determine the safety and efficacy of coronary pulsed mid-infra-red laser angioplasty. The laser was coupled with a novel 2.0 mm multifiber catheter consisting of 37 optical fibers of 150 microns each arranged concentrically around a 0.018-inch central lumen and a soft leading tapered distal tip to maintain coaxial alignment and position plaque in front of fibers. The laser was operated at 500 millijoules/pulse, 3.5 Hz, and 250 microseconds/pulse. Twenty-three patients with stenosis or occlusion of the left anterior descending or right coronary artery were selected for laser treatment. In three patients the catheter could not be positioned against the obstruction. In the 20 remaining patients laser angioplasty increased the diameter of the lumen from 0.3 +/- 0.3 mm to 1.4 +/- 0.3 mm and reduced the stenosis from 91 +/- 8% to 57 +/- 10%. In three patients "stand-alone" laser treatment was sufficient. In 17 patients balloon dilatation further reduced the stenosis to 20 +/- 18%. In two patients who had previously undergone unsuccessful balloon angioplasty with high inflation pressure, laser angioplasty allowed subsequent successful dilatation with low inflation pressure. There were no deaths, perforations, dissections, or arrhythmias. One patient had abrupt reclosure 24 hours after the procedure. Spasm occurred in four patients, and six patients had chest sensations during laser emission. Thus mid-infra-red pulsed coronary laser angioplasty is safe and effective for recanalization of stenosed and totally occluded arteries. The efficacy may be sufficient for "stand-alone" laser treatment. The technique may improve the efficacy of balloon angioplasty in cases of unsuccessful primary dilatation.     

Increased primary success rate in coronary angioplasty using a guide wire with attached balloon (microprobe)

In 15 cases of 350 consecutive coronary angioplasties conventional low profile balloon catheters did not traverse the stenosis or occlusion over the guide-wire. A balloon on a wire device ("Microprobe", 2 mm) passed the stenosis or occlusion easily with a good primary result in 14 cases. The angioplasty procedure could then be completed with a larger standard balloon catheter. Use of the balloon on a wire device expands the technical facilities of angioplasty and increases the primary success rate in technically difficult cases.     

Pressure wire guide provisional coronary stent implantation

OBJECTIVES: Whether coronary artery lesion successfully dilated by balloon angioplasty should be stented or not is unclear. The purpose of this study is to evaluate the provisional stent implantation method assessing residual ischemia by pressure wire. METHODS: Thirty-one patients with de-novo lesions suitable for stenting were enrolled in a pressure wire guided provisional stent study. The pressure wire was used to assess the fractional flow reserve(FFR) before and after balloon angioplasty. When the FFR after angioplasty was less than 0.75, stent implantation was planned. Patients with lesions consisting of an intermediate stenosis proximal to the target lesion, chronic total occlusion, bypass graft and left main lesion were excluded from the study. Stent implantation was permitted even if the FFR was more than 0.75 when the operator thought stenting was necessary. Medical treatment was given with aspirin 162 mg/day, cilostazol 200 mg/day for 6 months and additional ticlopidine 200 mg/day for a month after stenting the lesion. RESULTS: Target vessel was the left anterior descending coronary artery in 19 lesions, the right coronary artery in 3, and the circumflex coronary artery in 9. Stent implantation was performed in seven (23%) of 31 lesions and the other 24(77%) lesions were treated with only balloon angioplasty. The FFR before intervention was 0.58 +/- 0.16, and improved to 0.87 +/- 0.07 (p < 0.0001). Percentage diameter stenosis before intervention was 70.7 +/- 12.6% and improved to 20.1 +/- 13.3% (p < 0.0001) after intervention. There was no major cardiac event (death, coronary artery bypass grafting, myocardial infarction, stent thrombosis). Six months follow-up angiography was performed in 27 patients (87%). Angiographic restenosis (percentage diameter stenosis > or = 50%) was found in four patients (15%). A new lesion was found in two patients. Target vessel revascularization was performed in six patients (21%). CONCLUSIONS: Lesions successfully dilated by balloon angioplasty with FFR > or = 0.75 do not require stenting.     

Inadvertant balloon extrusion through a side hole in a guiding catheter

A patient presented with an acute inferior myocardial infarction. Coronary angiography in the acute stage revealed total occlusion of the right coronary artery. Reperfusion was obtained after intracoronary infusion of 250,000 units of streptokinase. Angioplasty was subsequently performed because of a high grade residual stenosis. An 8-French right Judkins guiding catheter with a single side hole (USCI), a 3.0 mm balloon dilatation catheter (ACS), and a 0.018 high torque floppy guide wire (ACS) were used. After successful angioplasty angiography was repeated with the guide wire in the RCA, but the balloon was withdrawn into the guiding catheter. After injection of contrast, it was impossible to withdrawn the balloon catheter out of the guiding catheter. Fluoroscopy revealed extrusion of the balloon through the side hole in the guiding catheter.     

Influence of balloon size and stenosis morphology on immediate and delayed elastic recoil after percutaneous transluminal coronary angioplasty.

After successful coronary angioplasty, the minimal luminal diameter of the dilated coronary artery segment is generally smaller than the diameter of the largest balloon catheter at the maximal inflation pressure. The determinants of this phenomenon were studied in 28 patients. Biplane angiograms were obtained after intracoronary administration of isosorbide dinitrate (1 mg) before, immediately and 24 h after coronary angioplasty. Balloon and coronary luminal diameters were measured by automated contour detection. Immediately after the procedure, the difference between inflated balloon diameter and minimal luminal diameter averaged 0.93 +/- 0.43 mm for the entire group and was greater both in eccentric stenoses (1.13 +/- 0.39 vs. 0.70 +/- 0.36 mm; p less than 0.01) and after angioplasty with an oversized balloon (1.20 +/- 0.37 vs. 0.71 +/- 0.33 mm; p less than 0.005). At 24 h, the balloon - minimal luminal diameter difference was unchanged at the group level (0.86 +/- 0.38 mm, but the minimal luminal diameter increased significantly in the subgroup of coronary segments dilated with an oversized balloon (1.97 +/- 0.37 vs. 1.81 +/- 0.28 mm; p less than 0.05). Thus, the difference between the minimal diameter of a dilated coronary segment immediately after a successful coronary balloon angioplasty procedure and the maximal diameter of the inflated balloon catheter is dependent both on eccentricity of the stenosis and on the balloon/artery diameter ratio. Moreover, the increase in minimal luminal diameter 24 h after angioplasty performed with an oversized balloon suggest that in addition to elastic recoil partly reversible factors related to vessel barotrauma are involved.     

Coronary angioplasty with 7F guiding catheters

The performance of 7F guiding catheters for percutaneous transluminal coronary angioplasty (PTCA) was investigated in 300 patients. A total of 233 patients had single-vessel PTCA and 67 had multivessel PTCA. Angioplasty was attempted for 371 lesions (141 [38%] in the left anterior descending, 124 [33%] in the right coronary artery, and 95 [26%] in the left circumflex coronary artery or their branches; 10 [3%] in a bypass graft, and one in the left main stem). The mean degree of stenosis was 86 +/- 11% (range 60% to 100%). The monorail technique was used in 83%, and balloon-on-a-wire devices were used in 6% of cases. The balloon sizes varied between 2.0 and 4.25 mm. There was a 98% technical success rate for the 325 nontotal lesions. Five could not be crossed with the wire. Exchange to an 8F guiding catheter was done in four cases (1.2%) and yielded success in two of them. In 46 occlusions the success rate was 72%. Nine were failures due to an inability to cross the wire, another two were balloon failures, and in two cases the residual stenosis was greater than 50%. The mean residual stenosis of successful cases was 24 +/- 18%. Overall, the primary success rate was 95%. The complications were: in-hospital death in five patients (1.7%); infarction in 12 (4%); emergency bypass surgery in one; and significant inguinal hematoma in five (1.7%). Coronary angioplasty through 7F guiding catheters yields a high success rate with less coronary wedging and a smaller puncture hole.