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)     

Excimer laser angioplasty in coronary artery disease.

The results of coronary excimer laser angioplasty were evaluated in 70 patients. Forty-five patients had laser angioplasty of coronary stenoses. Twenty-five patients in a total of 35 attempts had wire-guided laser recanalization of chronic coronary occlusions, resulting in a success rate of 71%. Immediate results in both groups demonstrated the efficacy of this technique without serious side-effects. Stenoses were reduced from 90 +/- 5% to 48 +/- 18% diameter reduction (mean +/- standard deviation) by excimer laser angioplasty. Residual stenosis in recanalized vessels after laser angioplasty was 52 +/- 19%. In slightly more than half of the patients with a residual stenosis greater than 50% after excimer laser angioplasty, subsequent balloon angioplasty was performed for further stenosis reduction. While satisfactory immediate results were achieved by excimer laser angioplasty intermediate follow-up revealed a restenosis rate in the same range as with balloon angioplasty.     

Magnum wire for balloon recanalization of chronic total coronary occlusions

A new guidewire (Magnum wire, Schneider) was developed for balloon recanalization of chronic total coronary occlusions. This 0.021-inch solid-steel wire with a floppy tip equipped with a 1-mm diameter "olive" is used like an ordinary guidewire, fits conventional balloon catheters and provides excellent steerability. Magnum wires were used in 50 consecutive chronic total coronary occlusions (mean +/- standard deviation duration 8 +/- 21 months, range 1 day to 10 years; mean length 1.1 +/- 0.8 cm, range 0.2 to 4.0). All occlusions were reached (in 23 right, 18 left anterior descending, 8 left circumflex coronary arteries and 1 diagonal branch) and 30 (60%) were recanalized (1 reoccluded during the procedure, and in 3 patients the Magnum wire did not completely cross the occlusion but enabled the previously impossible passage of a conventional wire). The mean age of the occlusion was 3 +/- 4 months in successful and 17 +/- 33 months in unsuccessful procedures (p = 0.04) and the mean length was 1.1 +/- 0.9 and 1.3 +/- 0.6 cm, respectively (p = 0.4). In 17 patients, conventional techniques had been exhausted before the Magnum wire attempt, which was successful in 8 (47%). In 33 patients the Magnum wire was tried first, with success in 22 (67%). Conventional techniques were subsequently tried in 9 of the 11 failures (none was successful). Of the 38 procedures carried out with a second, improved version of the Magnum wire, 26 (68%) were successful.(ABSTRACT TRUNCATED AT 250 WORDS)     

Reopening of Chronic Coronary Artery Occlusions by Low Speed Rotational Angioplasty

Following successful application in chronic peripheral artery occlusions, rotational angioplasty was refined and miniaturized for application in patients with chronic coronary artery occlusions. The new catheter system comprises a motor-driven rotating inner steel catheter made up of several steel coils providing maximum elasticity and complete torque control with an olive-like rounded tip (1.0–1.7 mm). The catheter has a lumen for contrast injection and a shielding plastic tube. It is introduced through a conventional 8 Fr guiding catheter. The slowly rotating (200 RPM) catheter passes nontraumatically through the occlusions, thus creating a new channel with smooth contours in a "remodeling" fashion. Once the channel (diameter 1–1.5 mm) is confirmed angiographically, balloon angioplasty is performed over an exchange wire in conventional technique. The new technique was applied to patients with chronic coronary occlusions. Reopening was first attempted with conventional guidewire technique. If the occlusion could be probed with the guidewire, patients were excluded from the study. Twenty patients in whom the occlusion could not be probed with a wire were studied: 1 ACVB, 2 LAD, and 17 RCA. Average duration of occlusion was 7.4 months; it exceeded 3 months in 15/20 and 6 months in 12/20 patients. Successful reopening was achieved in 9/20 (3 from the first 10, 6 from the second 10 patients). No vessel wall perforation or any other severe complication was encountered. Residual stenosis diameter ranged from 30%–70%. Duration of occlusion was similar among patients from the successful and unsuccessful group. It is concluded that with low speed rotational angioplasty reopening of chronic coronary artery occlusions can be achieved in a considerable part of patients in whom conventional technique is unsuccessful. (J Interven Cardiol 1989:2:3)     

New option for balloon recanalization of total coronary occlusions.

In 9 out of 12 patients with a total coronary occlusion but definite signs of viable myocardium a new approach for the recanalization procedure was successfully employed: Following recanalization using an on-the-wire 2.0 or 2.5 mm angioplasty catheter, a standard coronary guidewire was placed along the angioplasty catheter. After withdrawal of the catheter, over-the-wire angioplasty with an appropriately sized balloon was performed for final dilatation. Pending further studies in a larger patient population, this new method may offer an alternative approach for revascularization of total coronary occlusions.     

New option for balloon recanalization of total coronary occlusions

In 9 out of 12 patients with a total coronary occlusion but definite signs of viable myocardium a new approach for the recanalization procedure was successfully employed: Following recanalization using an on-the-wire 2.0 or 2.5 mm angioplasty catheter, a standard coronary guidewire was placed along the angioplasty catheter. After withdrawal of the catheter, over-the-wire angioplasty with an appropriately sized balloon was performed for final dilatation. Pending further studies in a larger patient population, this new method may offer an alternative approach for revascularization of total coronary occlusions.     

"Wireless" laser recanalization of chronic total coronary occlusions

Chronic total occlusions in particular, completely obstructed aorto-ostial lesions are among the most challenging targets in interventional cardiology. Excimer laser is a debulking technology for revascularization of complex lesions. Treatment of total occlusions with laser angioplasty can be applied providing that a guidewire traverses the entire length of the occlusion prior to device activation. In many patients with total occlusions, a guidewire is unable to penetrate the target stenosis. This communication presents a new technique termed "wireless" laser recanalization. This approach entails recanalization of a total occlusion with a laser catheter without a leading guidewire.     

Recanalization of chronic coronary occlusions using a laser wire

Between August, 1993–December, 1994, recanalization of a chronically occluded coronary artery was attempted in 412 patients, with an overall success rate of 77%. The main reason for failure was subintimal tracking of the guide wire. However, in 13 patients, advancing the guide wire was not possible either subintimally or in the former true lumen. In 8 of these 13 patients with failed conventional recanalization, a second attempt was made using a 0.018′ laser wire. The suspected occlusion duration was 6 wk–6 yr, and the occlusion length 6–21 mm. Successful crossing of the occlusion was achieved in 7 of 8 patients. One patient experienced pericardial hematoma without severe clinical consequences. Adjunctive conventional laser angioplasty and/or balloon dilatation led to a residual stenosis of <50% in 7 patients. The laser wire technique may become an important new method for recanalizing chronic total coronary occlusions in selected patients. © 1996 Wiley-Liss, Inc.     

Percutaneous coronary laser angioplasty in a patient with chronic total obstruction of the right coronary artery

Percutaneous coronary laser angioplasty was performed in one patient with total occlusion of right coronary artery without further balloon angioplasty in the ablated site. First of all, we used intracoronary urokinase in a total amount of 60,000 units that resulted in opening the total occluded right coronary artery to provide a passage of guidewire of laser catheter. Then a laser catheter was inserted through the guide catheter and its metal cap was in contact with the atherosclerotic lesion. The Nd:YAG laser was activated to vaporize the lesion (total energies of 54 J). Finally, the degree of residual stenosis was reduced from 95% to 20%. Percutaneous coronary laser angioplasty is a new method in treating coronary artery disease, yet it is still in its infant stage and further work is needed to develop this technological procedure.     

Stent or angioplasty after recanalization of chronic coronary occlusions? (The SARECCO Trial).

This study tests whether stent implantation without anticoagulation after catheter recanalization of coronary occlusions can improve outcome compared with balloon angioplasty alone. One hundred ten patients were randomly assigned to angioplasty alone (no stent group) or stent implantation (stent group) after successful recanalization and balloon angioplasty. The type of stent and angioplasty technique utilized were decided by the operator. The acute procedural success in both groups was 100%. The acute minimal lumen diameter (MLD) was 1.85 +/- 0.44 mm in the no stent group versus 2.54 +/- 0.53 mm in the stent group (p <0.01). The diameter stenosis was 21 +/- 13% versus 3 +/- 14% (p <0.01). This was achieved not only by the stent implantation itself but primarily by a larger maximum balloon diameter in the stent group after stent implantation (3.32 +/- 0.55 mm vs 2.86 +/- 0.4 mm, p <0.05). After 4 months, the MLD was 1.15 +/- 0.73 mm in the no stent group versus 1.81 +/- 0.9 mm in the stent group (p <0.01). The diameter stenosis was 56 +/- 29% versus 34 +/- 28% (p <0.01). After 2 years, event-free survival was 26% in the no stent group and 52% in the stent group (p <0.05). Thus, acute and long-term procedural and angiographic success of stent implantation without anticoagulation after recanalization of total coronary occlusions is superior to that of balloon angioplasty alone. This beneficial effect is mainly the result of the larger balloon diameters, which may be used after stent implantation.     

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.     

Laser angioplasty of restenosed coronary stents: results of a multicenter surveillance trial. The Laser Angioplasty of Restenosed Stents (LARS) Investigators.

OBJECTIVES: This study evaluated safety and efficacy of excimer laser angioplasty for treatment of restenosed or occluded coronary stents. BACKGROUND: Balloon angioplasty of in-stent restenosis is limited by a high recurrence rate. Debulking by laser angioplasty is a novel concept to treat in-stent restenosis. METHODS: A total of 440 patients with restenoses or occlusions in 527 stents were enrolled for treatment with concentric or eccentric laser catheters and adjunctive balloon angioplasty. RESULTS: Laser angioplasty success (< or =50% diameter stenosis after laser treatment or successful passage with a 2.0-mm or 1.7-mm eccentric laser catheter) was achieved in 92% of patients. Adjunctive balloon angioplasty was performed in 99%. Procedural success (laser angioplasty success followed by < or =30% stenosis with or without balloon angioplasty) was 91%. There was neither a significant difference in success with respect to lesion length, nor were there differences between small and large vessels or native vessels and vein grafts. Success was higher and residual stenosis lower using large or eccentric catheters. Serious adverse events included death (1.6%, not directly laser catheter related), Q-wave myocardial infarction (0.5%), non-Q-wave infarction (2.7%), cardiac tamponade (0.5%) and stent damage (0.5%). Perforations after laser treatment occurred in 0.9% of patients and after balloon angioplasty in 0.2%. Dissections were visible in 4.8% of patients after laser treatment and in 9.3% after balloon angioplasty. Reinterventions during hospitalization were necessary in 0.9% of patients; bypass surgery was performed in 0.2%. CONCLUSIONS: Excimer laser angioplasty with adjunctive balloon angioplasty is a safe and efficient technology to treat in-stent restenoses. These data justify a randomized comparison with balloon angioplasty.     

A novel approach to facilitating balloon crossing chronic total occlusions: the "wire-cutting" technique

Background: Following successful guidewire passage, inability to cross the occluded lesion with a balloon is the most common cause of procedural failure for percutaneous recanalization of chronic total occlusions (CTOs). We sought to evaluate the efficacy of “wire‐cutting” technique for facilitating the balloon passage through the lesion during CTO‐percutaneous coronary intervention. Methods: Sixteen consecutive patients with CTOs were treated by “wire‐cutting” technique when a lubricious balloon could not be passed through the lesion after successful guidewire crossing. The main process of the “wire‐cutting” technique involved: inserting 2 percutaneous transluminal coronary angioplasty (PTCA) guidewires (A and B) into the distal true lumen; advancing a balloon over guidewire A to the site of the occlusion abutting the proximal cap, the balloon was then inflated and guidewire B was pressed between the balloon and the proximal cap; rapidly withdrawing guidewire B produced a cutting power that crushed the proximal cap thus facilitating balloon crossing. Technique success was defined as balloon having crossed CTO lesions successfully after performing wire‐cutting procedure. Results: Both technical success and procedural success were obtained in 10 (62.5%) cases. Technique failure occurred in 6 (37.5%) cases, of which 2 were due to the inability to place a second guidewire into the distal true lumen and the other 4 were due to severe coronary calcification. Of these 4 failures, 2 have final procedure success with the use of Rotablator and the remaining 2 patients were referred for bypass surgery. Major complication included severe coronary dissection that occurred in 1 (6.3%) patient, which was successfully treated by stenting. No other complications were observed. Conclusion: The wire‐cutting technique may be considered as a simple and effective approach for facilitating balloon crossing resistant CTO lesions. (J Interven Cardiol 2012;25:297–303)     

In vivo ultrasound arterial recanalization of atherosclerotic total occlusions

The purpose of this study was to assess the potential of intraarterial ultrasound for in vivo recanalization of atherosclerotic total occlusions. Ultrasound energy at a frequency of 20 kHz was applied with a prototype solid wire probe to 12 surgically implanted occluded human atherosclerotic arterial xenografts, 9 of which were calcified, as well as to the intimal surface of 12 normal canine arteries. In both the normal canine arteries and the atherosclerotic occluded xenografts, there was no angiographic evidence of vasospasm, thrombosis or arterial dissection. Eleven of the 12 atherosclerotic complete arterial occlusions were resistant to passage of a conventional guide wire or probe without ultrasound energy. However, the occlusions were recanalized after administration of 15 s to 4 min (mean 1.5 +/- 1.3 min) of intermittent ultrasound energy. After ultrasound, 8 of the 12 vessels underwent balloon angioplasty. Angiographic residual stenosis after ultrasound alone was 62 +/- 24% and after combined ultrasound and balloon angioplasty, 29 +/- 13%. Although routine angiography did not reveal arterial emboli, high resolution cut films did demonstrate a few distal nonocclusive thrombi of a size similar to that reported with other recanalization methods. Histologic studies demonstrated changes similar to those after balloon angioplasty, with focal cracking of the fibrotic and calcified plaque. The findings demonstrate that ultrasound energy applied through a catheter delivery system can be used in vivo to open completely obstructed atherosclerotic vessels. These studies suggest that it might be clinically feasible to use the ultrasound probe to create a lumen, allowing subsequent balloon dilation.     

Percutaneous peripheral ultrasonic angioplasty

We previously reported the initial use of percutaneous catheter delivered ultrasound energy for arterial recanalization in eight patients with peripheral vascular disease. All patients had severe claudication. There were four cases with total occlusion and four with high grade stenoses in a superficial femoral or popliteal artery. A prototype ultrasound probe, with a frequency of 20 kHz and a power output of 20 to 25 watts/cm2 was ensheathed in a 7F catheter and advanced to the occlusions with angiographic guidance. Three of four complete occlusions were recanalized in less than 120 s resulting in a 54 +/- 5% residual diameter stenosis. Ultrasound energy applied to isolated stenoses reduced them by 40%, from 77 +/- 14% to 37 +/- 21%. Further treatment with balloon angioplasty resulted in a mean residual stenosis of 20 +/- 9%. There was no angiographic or clinical evidence of arterial emboli, dissection, spasm, or perforation. Clinical follow-up and Doppler ankle-brachial indices were performed at one, three and six months after combined ultrasound and balloon angioplasty. Two occlusions recurred, both within the first three months, detected by return of claudication and an abnormal ankle/brachial index, and documented by angiography. Repeat balloon angioplasty of standard methods was performed in one, but the vessel again reoccluded. The other five patients with primary technical success have continued patency both clinically and by ankle/brachial index measurement. Percutaneous catheter delivered ultrasound energy appears promising in peripheral vessels to reduce arterial stenoses and recanalize complete arterial obstructions. The long-term findings from this pilot study were insufficient to assess if ultrasound has any effect on restenosis.     

Excimer Laser in Percutaneous Coronary Intervention of Device Uncrossable Chronic Total and Functional Occlusions

Device uncrossable lesions are a challenge in interventional cardiology and despite improvements in balloon and microcatheter profile, rotational atherectomy is necessary in some circumstances in order to ablate and traverse the lesion. Nevertheless, the application of rotational atherectomy requires utilization of a specific wire, Rotawire, which is not always so easily navigable. Debulking of device uncrossable lesions can be performed by coronary laser over any kind of angioplasty guidewire. We present a series of six patients with chronic total (100%) and functional occlusions (99% stenosis) in whom after successful wire crossing, microcatheter failed to traverse the lesion. After coronary laser performance, 5 out of 6 lesions were successfully dilated, achieving a successful final angiographic result of 83.3%.     

Anchoring technique to improve guiding catheter support in coronary angioplasty of chronic total occlusions.

The primary reason for unsuccessful angioplasty of chronic total occlusions (CTOs) is an inability to pass the guidewire through the occlusion. Optimal guiding catheter support is a prerequisite for successful angioplasty of CTO. We performed guidewire manipulation by anchoring a balloon in a side-branch vessel in order to achieve adequate guiding catheter support. With this novel anchoring technique, we successfully achieved guidewire passage through the CTO.     

Immediate and long-term outcome of recanalization of chronic total coronary occlusions

Eighty-three consecutive patients with 85 coronary total occlusions undergoing coronary angioplasty were retrospectively studied. Patients were divided into two groups according to the occlusion age that was < 30 days (subacute total occlusion [STO]: 25 patients; range 1-30 days) or > 30 days (chronic total occlusion [CTO]: 58 patients; range 3-144 months). All procedures were carried out using a hydrophilic guidewire. Clinical success, consisting of crossing the lesion, balloon dilatation, stent deployment without complications, was 96% in STO and 81% in CTO. Multiple stepwise logistic regression analysis identified a family history of coronary artery disease (CAD), left anterior descending and right coronary artery occlusions as independent predictors of a successful procedure. No major events occurred during or immediately after the angioplasty. After a mean follow-up of 24 +/- 2 months, no difference was found in survival or freedom from myocardial infarction or target vessel revascularization among the STO and CTO patients. Successful recanalization by using a hydrophilic guidewire was achieved in a high percentage of chronic total occlusions with a low incidence of complications and a satisfactory late clinical outcome. Family history of CAD and occlusion of left anterior descending or right coronary arteries are independent predictors of procedural success.     

Fluorescence-guided laser-assisted balloon angioplasty in patients with femoropopliteal occlusions

In 12 patients (aged 64 +/- 10 years) with femoropopliteal occlusions (1-27 cm; average, 8.4 cm length) that could not be recanalized by standard guidewire-balloon angioplasty techniques, percutaneous laser-assisted balloon angioplasty was performed by use of a new fluorescence-guided dual-laser system. Plaque detection by 325-nm laser-excited fluorescence spectroscopy provided real-time feedback control to a 480-nm pulsed dye laser (2-microseconds pulses) for atheroma ablation. By means of a common 200-microns optical fiber, after diagnostic fluorescence sensing, computer algorithms directed a fire or no-fire signal (5 Hz) to the treatment laser for selective plaque removal. Laser recanalization (15-50 mJ/pulse) was successful in 10 of 12 patients; this procedure was followed by definitive balloon angioplasty in seven of 12 patients with increased ankle/arm indexes (from 0.60 +/- 0.12 at baseline to 0.84 +/- 0.11 after treatment, p = 0.0043). In laser and balloon angioplasty failures, all femoropopliteal occlusions were heavily calcified, and there were two mechanical guidewire perforations without clinical sequelae. Ablation of calcified lesions required higher pulse energies and greater total energy per centimeter of recanalized tissue (1,837 +/- 1,251 mJ/cm vs. 90 +/- 39 mJ/cm, p = 0.0036). Fluorescence spectroscopy (n = 219 sites) was helpful in flush occlusions and correctly identified plaque, underlying media, and thrombus by changes in fluorescence intensity, shape, and peak position. Thus, when fluorescence-guided laser angioplasty was used in a subgroup of patients refractory to standard angioplasty techniques, primary recanalization and subsequent balloon angioplasty of femoropopliteal occlusions was successful in 83% and 58% of the patients, respectively. Importantly, treatment of heavily calcified lesions accounted for all of the failures and will require modified delivery systems to create larger primary channels and to increase catheter-tip control, which should improve clinical results in the future.     

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.