Probe, a balloon wire: initial experience

Coronary angioplasty is unsuccessful in less than 3-5% of cases because the balloon catheter fails to follow a guidewire that has traversed a lesion. Between June 1986 and August 1987, 31 lesions were unable to be crossed with at least two standard angioplasty catheters. Finally, a 2.0-mm-diameter Hartzler LPS (ACS) was utilized and successfully crossed and dilated 16 out of 31 lesions (52%). In the remaining 15 lesions, the Probe (USCI) 2.0 mm diameter x 1.5 cm long balloon wire was able to cross the lesions in 13 (82%) and successfully dilated 12. In one case, lesion rigidity prevented the balloon from expanding at 14 atm. A right coronary artery lesion was attempted in 11 cases, and a left anterior descending and circumflex artery lesion in two patients each. No complications were encountered. In seven out of 12 successful Probe cases, a larger balloon catheter was used to further dilate the artery. This new balloon wire has increased our success rate in severe stenoses and in tortuous vessels with severe distal lesions, in which presently available angioplasty equipment has failed.     

Preliminary experience with 5 and 6 French diagnostic catheters as guiding catheters for coronary angioplasty

With the reduction in profile of balloon dilation catheters, until recently, it has been the internal dimensions and performance of the guiding catheter that has mandated the use of 7, 8 or 9 French (F) systems for the performance of percutaneous transluminal coronary angioplasty (PTCA). A new 5F catheter design (Sherwood Medical Co., St. Louis, MO) provided a large inner lumen (0.4") permitting use of 0.20-0.22" fixed-wire PTCA balloon catheters with good coronary visualization. Potential advantages include reduced coronary artery ostial trauma and catheter induced damping and enhanced patient comfort. We report our initial experience in 14 patients undergoing PTCA with a 5 and 6F guide/fixed-wire system. Mean age was 63 +/- 10 (43-78 years). PTCA indications: Cardiogenic shock (1), post-myocardial infarction angina pectoris (2), grade III angina (5) and unstable angina pectoris (6). Vessel attempted: Left anterior descending (3), circumflex (4), obtuse marginal (2), diagonal (1), right coronary artery (3), and internal thoracic artery (1). Twelve patients had femoral approach; two brachial approach. The USCI Probe (USCI Division, Billerica, MA) was used in 8 lesions and SCIMED ACE (SCIMED Life Systems, Maplegrove, MN) catheter in 7 lesions. Successful 5 or 6F guide/fixed-wire dilations reduced the stenosis (77 +/- 14 to 37 +/- 30%) and were successfully performed in 79% (11/14). One 5F patient required 8F guiding catheter and was dilated with 2.0 fixed-wire balloon. A second failed 5F PTCA could not be dilated with any larger conventional system. A third total occlusion could not be crossed with a guidewire or fixed wire balloon. No patient had a complication.(ABSTRACT TRUNCATED AT 250 WORDS)     

Probe™, a balloon wire: Initial experience

Coronary angioplasty is unsuccessful in <3–5% of cases because the balloon catheter fails to follow a guidewire that has traversed a lesion. Between June 1986 and August 1987, 31 lesions were unable to be crossed with at least two standard angioplasty catheters. Finally, a 2.0-mm-diameter Hartzler LPS (ACS) was utilized and successfully crossed and dilated 16 out of 31 lesions (52%). In the remaining 15 lesions, the Probe^TM (USCI) 2.0 mm diameter × 1.5 cm long balloon wire was able to cross the lesions in 13 (82%) and successfully dilated 12. In one case, lesion rigidity prevented the balloon from expanding at 14 atm. A right coronary artery lesion was attempted in 11 cases, and a left anterior descending and circumflex artery lesion in two patients each. No complications were encountered. In seven out of 12 successful Probe^TM cases, a larger balloon catheter was used to further dilate the artery. This new balloon wire has increased our success rate in severe stenoses and in tortuous vessels with severe distal lesions, in which presently available angioplasty equipment has failed.     

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.     

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.     

The Falconª Eccentric Coronary Balloon Angioplasty Catheter: A Randomized Safety and Efficacy Study

Percutaneous coronary angioplasty (PTCA) is usually performed using concentric shaped balloon catheters with the guidewire passing through the center of the shaft. The Falcona balloon catheter features a guide wire lumen on the outside of the balloon so that an eccentric balloon catheter profile is obtained concentrating the dilating force on the wire supported side, allowing lower inflation pressures and potentially causing less vessel injury. The aim of this study was to evaluate the safety and efficacy of this new balloon catheter in patients with stable and unstable angina. In 95 prospectively randomized patients, 57 lesions were dilated with a concentric balloon and 51 with the eccentric balloon. Technical success in the two groups was similar (73.3% vs. 74.5% control vs. Falcon respectively). Procedural success was 96.5% vs. 96.1% in the control and Falcon groups respectively. The mean increase in minimum luminal diameter (MLD) was 1.01 +/- 0.41 mm in the control vs 0.85 +/- 0.45 mm in Falcon (p = 0.053). There was an increase in type A dissections in the Falcon group 18 (36.75%) vs. 10 (19.23%) in the control group (p = 0.07) with no difference in stent implantation, myocardial infarction, CABG or death between the two groups. All patients with a technically successful PTCA were followed up. Seventeen (43.6%) in the control and 11 (32.4%) in the Falcon had repeat coronary angiography (p = 0.38), 12 (30.8%) vs. 7 (20.6%) had repeat PTCA (p = 0.37) and time to PTCA was 116 +/- 70 days vs. 154 +/- 103 days respectively (p = 0.36). The Falcon performed technically as well as the concentric balloons. Despite a smaller MLD and increase in Type A dissections there was no associated increase in complications or reintervention for restenosis. Further investigation is required to evaluate the role of this mechanism of dilatation in restenosis.     

Angioplasty of total coronary occlusions using combination of intracoronary Probing Catheter and balloon on wire Probe.

We describe our experience with a technique for PTCA of total coronary occlusions using the ultra low profile balloon on wire Probe. An intracoronary Probing Catheter was used to facilitate crossing the stenosis with a guide wire. This was followed by exchanging the guide wire for the Probe into the obstruction for balloon dilatation. This technique was used in 22 consecutive patients undergoing PTCA for chronic total occlusion. The total obstruction could be crossed by guide wire (0.014 flex or 0.016 standard) passed through Probing Catheter in 19 patients (86%). The obstruction could be successfully dilated by the Probe, delivered through the probing catheter, in 17 of these patients. Of the remaining 2 patients, one could be dilated by sequential dilatation using over the wire low profile balloon system and the other one by dilatation with the Probe, respectively. The Probing Catheter technique offers a new method to apply balloon on wire technology to the dilatation of chronic total coronary occlusions with very promising results.     

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.     

Percutaneous coronary rotational angioplasty in humans: preliminary report

Percutaneous coronary rotational angioplasty was attempted in 12 patients. The procedure was performed with a flexible rotating shaft with an abrasive tip, varying in diameter from 1.25 to 3.5 mm, tracking along a central guide wire. Among the 12 patients (mean age 58 years), 4 had a stenosis in the left anterior descending coronary artery and 8 a stenosis in the right coronary artery. After the guide wire crossed the stenosis, the abrasive tip was slowly advanced and several passes across the stenosis were made. The residual stenosis was measured with computerized automatic quantitative coronary angiography. Success was defined as a reduction of percent stenosis by greater than 20%. If residual stenosis remained significant (greater than 50%), the procedure was completed by balloon dilation. The device could not be inserted in 2 of the 12 patients. Five of the 10 patients underwent rotational angioplasty alone, and 5 had the procedure completed by balloon dilation. The stenosis was significantly enlarged from 0.56 +/- 0.31 mm to 1.26 +/- 0.28 mm. The outline of the vessel appeared smooth and regular. There were no complications related to the procedure and all patients were free of symptoms when discharged 2 to 3 days after the procedure. Thus, coronary rotational angioplasty is a simple and safe procedure allowing marked dilation of the narrowed segment. However, long-term follow-up is required for further evaluation.     

Coronary angioplasty with second generation Monorail catheters

The Monorail system (Schneider) consists of a balloon catheter in which the guidewire passes through the balloon itself, exits the catheter proximal to the balloon, and runs alongside its small shaft (3 French) through the length of the guiding catheter. It offers distinct advantages over conventional systems of coronary angioplasty. It facilitates contrast injections and permits rapid balloon exchanges. This system was used for coronary angioplasty in 273 unselected consecutive patients (age 59 +/- 10, mean 35 to 73 years). There were 216 patients (84%) undergoing single-vessel and 57 patients (16%) with multi-vessel coronary angioplasty. A total of 335 coronary stenoses were dilated, which included 35 total occlusions. The size of balloon used ranged from 2.0 to 4.25 mm (3.0 +/- 0.5 mm) and the severity of stenosis was 85 +/- 11%. Technical success was defined as a residual stenosis of less than 50% as determined angiographically. Clinical success was defined as technical success, and absence of a major inhospital complication defined as absence of myocardial infarction, lack of need for coronary arterial bypass surgery, and survival. The Monorail system was technically successful in 294/300 stenotic lesions (98%). It was clinically successful for 281 lesions (94%). Of the 35 total occlusions, technical success was obtained in 25 (71%). The residual stenosis of successful cases was 26 +/- 21%. The Monorail system was also successful in 5 patients with stenosis of more than 90% in whom conventional systems failed. The complications included acute occlusion causing acute myocardial infarction in 13 cases (5%), emergency coronary arterial bypass surgery in 1 patient (0.4%), and death in 4 patients (1.5%).(ABSTRACT TRUNCATED AT 250 WORDS)     

Clinical and angiographic procedural and mid-term outcome with new versus reused balloon catheters in percutaneous coronary interventions

BACKGROUND: To reduce procedural cost, cardiac centers increasingly use resterilized balloon catheters for percutaneous coronary interventions. Data addressing the procedural and mid-term outcome in a prospective randomized trial comparing new and resterilized balloons are not available. METHODS AND RESULTS: Percutaneous coronary interventions were performed at random in 238 consecutive patients with either new or 1-3 times reused balloon catheters. Crossing of the stenosis decreased from 96% with new balloon catheters to 93.2% (p=0.46), with 1 time reused balloon catheters to 81.8% (p=0.0056) with 2 times reused balloon catheters and to 80.8% (p=0.01) with 3 times reused balloon catheters. In all primary failures using resterilized balloon catheters, new ones of the same nominal diameter were successful. The 4.1 +/- 1.9 month angiographic follow-up rates were 96/124 (77.4%) for new balloon catheter, 35/44 (79.5%) for 1 time reused balloon catheters, 33/44 (75.0%) for 2 times reused balloon catheters, and 21/26 (80.8%) for 3 times reused balloon catheters (p for all >0.05). The late losses for new versus reused balloon catheters were 0.48 +/- 0.75 mm versus 0.73 +/- 0.79 mm (p=0.03). The percent stenosis was higher in reused versus new balloon catheters (51.9 +/- 23.2% v. 42.3 +/- 22.3%; p=0.0042) as was the restenosis rate [39/89 (43.8%] v. 31/96 (32.3%), p=0.13]. There was one death in reused balloon catheter category but no event of myocardial infarction. Rates of target lesion revascularizations were similar in stent recipients and more frequent after stand-alone balloon angioplasty with reused versus new balloon catheters [15/55 (27.3%) versus [5/59 (8.5%), p=0.01]. CONCLUSIONS: The use of two or three times resterilized balloon catheters of the type tested does not seem to be justified in stand-alone balloon angioplasty of de novo coronary stenoses and should be limited to stent procedures until data is available for other indications.     

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.     

Subselective Intracoronary Access Guide Catheters for use with the ProbeTM Balloon on a Wire Coronary Dilatation Device

Subselective coronary access guide catheters are described for use with the Probe^TM balloon on a wire coronary dilatation device. These access catheters provide the following advantages over the "naked" Probe^TM: (1) Guide catheter stabilization, (2) Lesion access, (3) Lesion visualization, (4) Lesion crossing, and (5) Lesion protection. The Probe/access catheter system was used in 51 patients on 132 lesions (average 2.6 lesions/patient; range 1–8 lesions/patient) of which 116 (88%) were dilated successfully. Failures tended to be in total occlusions or in eccentric subtotal occlusions that could not be crossed with the Probe^TM tip wire. No patient required emergency coronary bypass. One patient sustained a small myocardial infarction within 24 hours of the procedure. One patient developed hemopericardium after rupture of a small branch coronary artery. One patient died from intracerebral bleeding due to thrombolytic and anticoagulant therapy. The Probe^TM access catheter system has several advantages over the Probe^TM device alone, and future developments can be expected to extend these benefits. (J Inter-ven Cardiol 1989:2:1)     

Validation of 4 French catheters for quantitative coronary analysis: in vivo variability assessment using 6 French guiding catheters as reference scaling devices

Although numerous studies have established the utility of 4 F catheters for routine coronary angiography, its adequacy for automatic quantitative coronary analysis has not been previously assessed. METHODS: In 32 consecutive patients, coronary angiography was performed sequentially with 4 F diagnostic catheters and 6 F guiding catheters after intracoronary nitroglycerin. A total of 43 lesions were evaluated for quantitative analysis using both types of catheter as scaling devices. Possible differences in the reference diameter, minimal luminal diameter and percent diameter stenosis were evaluated. All measurements were performed offline by the same operator and intraobserver variability estimation was performed by repeating the evaluation in 12 lesions randomly selected after 1 month. RESULTS: The mean reference diameter was 2.98+/-0.48 mm, mean minimal luminal diameter was 1.00+/-0.52 mm and percent diameter stenosis was 67.1+/-15.3%. Accuracy (mean difference of values) was 0.009 mm for reference diameter, 0.005 mm for minimal luminal diameter and 0.25% for percent diameter stenosis. Precision (mean standard deviation of the differences) was 0.17 mm for reference diameter, 0.19 mm for minimal luminal diameter and 5.93% for percent stenosis. Linear correlation for these three variables was 0.94, 0.93 and 0.93, respectively. Intraobserver variability analysis showed similar values for accuracy, precision and linear correlation. CONCLUSIONS: Angiography with 4 F catheters allows adequate quantification of luminal diameters as compared to most accepted clinical standards. These results may have implications for the selection of diagnostic catheters for routine follow-up assessment of percutaneous coronary interventions.     

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.     

Valvuloplasty of congenital aortic stenosis

While percutaneous transluminal valvuloplasty has largely replaced open commissurotomy for congenital pulmonary valve stenosis, the experience with valvuloplasty for congenital aortic stenosis is limited. Between August, 1984 and June, 1987, a total of 27 valvuloplasties were carried out in 25 patients with congenital aortic stenosis; nine infants and 16 patients ranging in age from four to 25 years (mean age 13 +/- 6 years). The indication for valvuloplasty was established on the basis of congestive heart failure or severe stenosis in infants and in the presence of a pressure gradient in excess of 60 mm Hg in those older than one year of age. In eight infants, valvuloplasty reduced the transvalvular pressure gradient from 73 +/- 5 to 36 +/- 9 mm Hg (p less than 0.01; Figure 1). In the 16 patients older than one year of age, the pressure gradient was reduced from 93 +/- 25 to 49 +/- 15 mm Hg (p less than 0.01; Figure 2). The size of the balloon chosen was based on two-dimensional echocardiographic measurements of the aortic ring diameter from inner edge to inner edge. In infants, coronary artery dilating catheters and balloon catheters with an inflated diameter of 4.2 to 8 mm were employed; in children, the balloon diameter selected was 1 to 3 mm less than that of the valve ring diameter, in 15 cases a single-balloon catheter and in one a trefoil catheter. After puncture of the femoral artery and retrograde advancement of a guide-wire into the left ventricle, the balloon catheter was positioned via the guide-wire across the aortic valve.(ABSTRACT TRUNCATED AT 250 WORDS)     

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.     

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.     

New technic for guidable balloon dilatation of coronary vessel stenoses

A new technique for steerable balloon dilatation is described. In contrast to the usual procedure the stenosis is first crossed by a long wire only. To minimize injuries to the vessel wall the wire is equipped with a thickened ball-shaped tip. After the stenosis has been crossed and the wire tip sufficiently advanced the balloon catheter is inserted over the long wire. If necessary the balloon catheter can be removed and another inserted without repeat crossing. If an occlusion is caused by the process of dilatation a perfusion catheter can be advanced distal to the occlusion. Perfusion can be performed with the aid of a simple syringe-tap system because the cross sectional area of this catheter is much larger than a single lumen of the double-lumen balloon catheter. This procedure even allows the dilatation of branching stenoses through the same guiding catheter whereas for the usually performed "kissing balloon" technique two guiding catheters are required. Preliminary experience with 80 patients has shown that crossing of stenoses is facilitated by the new technique because steering of the guide wire and display by contrast medium injections are unhindered. If required the balloon catheter can be changed for another one without difficulty. In the case of an occlusion the lesion can be crossed again without any risk and repeat dilatation or coronary perfusion can be performed.     

Coronary balloon angioplasty through diagnostic 6 French catheters

We investigated the use of ultralow profile balloon catheters (Scimed ACE, USCI Probe, Cordis, Orion) for coronary angioplasty through 6 French diagnostic catheters (Schneider, Cordis). Contrast injection was assisted with a Hercules pump (Cordis) in all cases. During 21 procedures, angioplasty of 27 lesions in 20 selected patients was attempted (1.3 lesion/procedure). Twelve lesions were in the right, 10 in the left anterior descending, and 5 in the left circumflex coronary artery. Balloon size varied between 2.5 and 3.5 mm. Twenty lesions could be successfully dilated (74%) through the 6 French catheter and 7 lesions required an exchange to a 7 French angioplasty guiding catheter. For 5 cases, another balloon was also necessary to complete the procedure. The final overall success rate was 100% per patient and per lesion and there were no major complications. Despite the small internal catheter lumen (1.22 mm) coronary visualization was adequate, and mechanical support was good. Failures of 6 French catheters were attributed to insufficient torque control and excessive friction when the balloon crossed the tapered end of the diagnostic catheter. Coronary angioplasty through a diagnostic 6 French catheter is feasible and may represent a reasonable alternative for simple cases that are done during the same session as the diagnostic angiography. Once available, 6 French high flow angioplasty guiding catheters without a tapered tip should improve success while retaining the advantage of a small femoral puncture site.