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Although directional coronary atherectomy permits the treatment of complex coronary lesions, its use is limited in patients with peripheral vascular disease by the need to use a large guiding catheter. We describe a patient in whom the right brachial approach was successfully used to perform atherectomy of a semi-protected left main coronary stenosis.
Side branch protection of bifurcation lesions with guide wires treated with directional coronary atherectomy has been performed safely in a small number of patients using a nickel/titanium (Nitinol) alloy guide wire. There is no information about the safety of using other guide wires in this scenario. The purpose of this study was to microscopically examine a variety of guide wires exposed to the directional coronary atherectomy (DCA) device in vitro. Eight common guide wires used in percutaneous coronary angioplasty were positioned in a side branch of a simulated coronary bifurcation and exposed to the operating DCA device. The guide wires were examined grossly and under scanning electron microscopy. The Nitinol guidewire suffered no discernible damage in comparison to varying degrees of damage seen on the other guide wires, and this guidewire appears to be best suited for side branch protection. Examination of the protecting guide wire and cutting cylinder used in the initial patients also showed no damage. Further clinical trials are necessary to assess the efficacy of DCA under such conditions.
Conventional techniques of coronary angioplasty for lesions at coronary bifurcations are well documented, are sometimes cumbersome, and have inherent limitations. We describe a technique for sequential atherectomy at coronary bifurcations. Further evaluation is needed to determine the overall safety, efficacy, applicability and durability of sequential directional atherectomy at coronary bifurcations.
Directional coronary atherectomy provides a predictable outcome in selected cases; however, DCA may still result in significant complications in a small number of patients. Although many of the complications are similar to those associated with PTCA, some of the complications are unique or more frequently observed with DCA. These complications are often preventable with adequate case selection and appropriate technique. Because of significant differences in the atherectomy procedure compared to PTCA, the operator should recognize and understand the technical differences to prevent potentially serious complications.
The size and rigid length of the directional coronary atherectomy catheter creates a new set of demands and constraints for guiding catheter manufacturers. Large lumen guides with gradual, rather than abrupt, curves are necessary, and a number of unique shapes have been developed to address native coronary and saphenous vein graft anatomy. The guiding catheter has a tendency to straighten and disengage from the coronary or graft ostium as the DCA device is advanced, and coaxial alignment of the body of the guiding catheter is essential to engage the atherectomy device. Power-positioning and deep seating of these large lumen, thin walled, and rather rigid guides should be avoided, to minimize ostial complications. These guiding catheters require modifications of usual techniques for introduction, manipulation and maintenance or coaxial alignment with the target vessel, as well as for withdrawal through the aortic bifurcation. Strategies for successful guiding catheter selection and utilization are outlined.
Percutaneous atherectomy using Atherotrack was performed in 5 patients with symptomatic femoro-popliteal artery stenosis. All patients were men and ages ranged from 37 to 70. Four lesions were atherosclerotic and 1 lesion was post-operative anastomotic stenosis following traumatic popliteal artery injury. There was no technical failure and all lesions were successfully dilated with no or minimal residual stenosis. API returned within normal limit and patients were symptom-free immediately after the procedure. We experienced no major complication related to this procedure. Excised specimen included thickened fibrous intima, atherosclerotic materials, calcification, internal elastic lamina and fibrous media. Follow-up DSA 5 months after procedure showed good patency in 4 cases, and they remained free from symptoms in this follow-up period. In those patients, lesions were generally short and eccentric, run-off was good, and only thickened intimal tissue was obtained. Those factors seem to promise long-term patency and to be good indications of atherectomy. Restenosis as well as recurrence of claudication, however, developed in one patient with DM, who had long, tight, complex stenosis and poor run-off. Considerable amount of medial tissue was found in this specimen. We suspect that those factors were associated with reduced long-term patency rates.
The most important factor to reduce late restenosis following directional coronary atherectomy is the technical provision of the largest luminal diameter as possible. However, the safety of deep arterial resection and the resulting arterial perforation or late aneurysm formation is questionable. This study examined the frequency of coronary artery aneurysm formation in patients treated by directional coronary atherectomy. Ninety-eight patients with 123 lesions were analyzed by quantitative angiographic and histologic data. Coronary aneurysms (ratio of dilated vessel segment to the adjacent reference segment > 1.2:1) occurred in seven patients (seven lesions: 5.7%). Specimens were categorized by the deepest layer retrieved. Forty lesions (32.5%) were treated by resection of the intima alone, 65 (52.8%) by resection of the medial tissues and 18 (14.6%) received resections of the adventitial tissues including fatty tissues in three lesions. Late coronary aneurysms occurred often in lesions with resection of adventitial tissue (38.9%) and occurred in all three lesions with resections of fatty tissues. Six coronary aneurysms occurred in the left anterior descending artery (six in segs. 6, 7), and one aneurysm in the left circumflex artery. Among the target lesions in which coronary artery aneurysms were formed, six lesions were primary lesions and one lesion was a restenotic lesion after percutaneous transluminal coronary angioplasty. Statistically, patients with coronary artery aneurysms frequently have associated hypertension (p = 0.02) but rarely diabetes mellitus (p = 0.05). Lesions with late aneurysms had significantly high specimen weight (p = 0.01) and a trend to lower postprocedure % diameter (p = 0.20). There was no significant preprocedural angiographic predictor of aneurysms such as minimal lumen diameter or reference vessel diameter.
Treatment of chronic total occlusions remains a limitation of percutaneous revascularization and is associated with lower immediates success and higher long-term restenosis rates compared to less severe stenoses. While part of the problem in dealing with total occlusions relates to successfully passing a wire across the occluded segment, most chronic occlusions contain large plaque burdens. Balloon dilatation sometimes falls to restore antegrade flow and often yields suboptimal angiographic results in these situations. Rotational atherectomy has proven useful in treating calcified and diffusely-diseased vessels and appears attractive for debulking lesions with large atheromatous plaques. We report our experience using rotational atherectomy in treating chronic total occlusions.
BACKGROUND: Percutaneous transluminal coronary angioplasty (POBA) of complex lesions is hindered by a lower success rate and a higher risk of complications. New devices are now available for treatment of this type of lesions (type B-C of the modified AHA/ACC classification). We present our experience in the treatment of calcified, ostial, angled and long coronary lesions by means of percutaneous transluminal coronary rotational ablation (PTCRA, Rotablator Heart Technology, Bellevue, Washington). MATERIAL AND METHODS: From June 1991 to November 1995 we performed 71 procedures of rotational atherectomy on 72 lesions in 62 patients. Twenty-three patients presented stable angina, 30 patients unstable angina and 9 silent myocardial ischemia. Thirty-five patients had single, 16 double and 11 triple vessel coronary artery disease. Left ventricular mean ejection fraction was 58 +/- 8%. The lesions attempted were classified as type A in 2 cases, B1 in 23 cases, B2 in 31 cases and C in 16 cases according to the AHA/ACC modified classification. Calcifications detected at coronary angiography were present in 66 lesions; 53 lesions were longer than 10 mm; 12 were more than 45 degrees angulated; 9 were at a bifurcation site and 3 were ostial in location. The vessels treated were in 1 case a protected Left Main Trunk, in 40 the Left Anterior Descending, in 9 the Circumflex and in 22 the Right Coronary Artery. We did not treat lesions containing visible thrombus or located on old saphenous vein grafts because of the high risk of peripheral embolization. An average of 2 +/- 1 burrs was used; the mean burr/vessel diameter ratio was 0.59 +/- .07. "Complementary" low pressure PTCA was performed in all but 4 cases ("stand alone procedure"). RESULTS: Primary success was obtained in 62/71 procedures (92%) and in 67/72 lesions (94%). There were two major cardiac events during the hospital stay: one death and one acute myocardial infarction which occurred respectively at four days and 48 hours after the procedure due to late occlusion of the vessel treated with primary success. In three cases the procedure was unsuccessful but uncomplicated: In one the stenosis could not be crossed, in a second case a residual stenosis > 50% was present, in a third case the procedure resulted in dissection and occlusion of a vessel served by good intercoronary collaterals. No emergency or elective coronary artery bypass surgery was necessary. Coronary spasm occurred in 6 cases (9%). In two of them spasm was refractory to intracoronary nitrates and Verapamil, and stent implantation was required. Urapidil, a selective alpha 1 blocker, completely abolished the occurrence of coronary vasospasm in the last 16 cases. A no reflow phenomenon was observed in two cases associated with mild CK-MB elevation. In conclusions: our experience suggests that rotational atherectomy performed on lesions with complex morphology, most of them calcified, is a safe and effective procedure which therefore can be undertaken even in hospitals without on site cardiac surgery. Our data on late restenosis are inconclusive because of the lack of angiographic follow up.
Directional coronary atherectomy was performed on a 69-year-old female with angina pectoris. She suffered from coronary perforation as a result of cardiac tamponade and shock. Pericardial drainage and hemostasis were performed immediately using a perfusion catheter. The patient was transferred to the operating room for perforation repair and coronary artery bypass grafting to the distal portion of the left anterior descending artery. The procedure was performed successfully. Although acute coronary perforation associated with directional coronary atherectomy is rare, it can be managed temporarily by a perfusion catheter and we successfully performed coronary artery bypass grafting.
The authors describe a rare case of circumflex coronary artery perforation during rotational coronary atherectomy complicated with cardiac tamponade and good outcome. The possible causes of perforation are discussed and the burr oversize (burr/artery ratio was 0.58) was refused. Shortening and artery plicature (accordeon effect) might have been the cause of this event. Quantitative measurement was made in order to strengthen this hypothesis. It is emphasized the importance of selecting lesions that should be submitted to rotational coronary atherectomy.
Arterial bypass grafting for occlusive disease is still considered the gold standard in the treatment of arterial occlusive disease. However, less invasive methods are available for select patients. Percutaneous balloon angioplasty has been shown to be effective in focal iliac artery stenosis, with patency rates of 50% to 90% at 5 years. Patency rates for femoropopliteal lesions are generally less than 50% at 2 years. Complications seen with balloon angioplasty often can be treated with arterial stents. Stents can be categorized into balloon-expandable, which provide a rigid scaffold to support the artery, self-expanding, which exert radial force to resist external compression, and thermal expanding stents, which allow for the use of a smaller introducer sheath. Another treatment option is atherectomy, in which the offending lesion is removed instead of fracturing and dilating the lumen. Although overall initial results of atherectomy have not been favorable, short lesions with eccentric atheroma or intimal hyperplasia, such as those seen in dialysis access fistulas or vein graft stenoses, may respond well.
In this case report of a patient undergoing angioplasty for cardiogenic shock during acute myocardial infarction, recurrent occlusion resulted in recurrence of shock. Atherectomy reestablished lasting patency and reversed the patient's hemodynamic collapse. Atherectomy deserves further investigation as a means to salvage vessel patency during unsuccessful coronary angioplasty.
We describe a case in which coronary balloon angioplasty failed to improve sequential lesions and resulted in a long area of dissection between the stenoses. Directional coronary atherectomy of the occlusive dissection produced excellent angiographic improvement to achieve a successful result and avoid the need for urgent coronary bypass surgery. Directional coronary atherectomy represents a potentially useful treatment for PTCA-induced coronary dissection.
The brachial approach adds a new dimension to rotational atherectomy. The two cases presented included a large ectopic right coronary artery and a right internal mammary graft where both outcomes were successful. These cases demonstrate that the brachial approach can facilitate rotational atherectomy when greater guide support is necessary.
During the initial perioperative period (1 mo to 1 yr) after saphenous vein coronary grafting, early stenosis and occlusion occurs in 5-8% of grafts due to intimal hyperplasia. We report a patient who developed ostial stenosis within 4 mo of bypass surgery at the aortotomy site of two vein grafts. Balloon angioplasty of the elastic stenoses did not provide significant luminal enlargement, but successful treatment of the lesions was obtained using directional atherectomy. Histological examination demonstrated intimal hyperplasia. Directional atherectomy may be an excellent technique for treatment of elastic ostial vein graft stenoses in lieu of conventional balloon dilatation.
In this case report of a patient presenting with an acute inferior wall myocardial infarction, the infarct conduit was a saphenous vein graft. Extraction atherectomy using the TEC successfully reestablished patency and reversed the patient's clinical symptoms. Extraction atherectomy is a feasible procedure during acute coronary events and deserves further investigation.
Background: The transient and generally nonfatal nature of unstable angina has impaired the accumulation of pathologic data and the definition of the pathoanatomy of this syndrome. Methods: Atherectomy specimens from patients enrolled in CAVEAT were examined for the presence of thrombus, foam cells, cholesterol clefts, media, and adventitia. Comparison of the pathologic findings was made according to clinical presentation in the following categories: stable angina, unstable angina, and recent myocardial infarction. Results: Patients with unstable angina had. a slightly higher incidence of thrombus when compared with patients presenting with stable angina (36% vs. 26%, p =.14). Within the unstable angina population some subgroups demonstrated a greater incidence of thrombus, including those whose pain was associated with ECG changes (43%, p =.07). The incidence of thrombus was highest among patients who had a myocardial infarction within 30 days (53%, p =.004) or within 14 days (58%, p =.003). No difference between the patient groups was detected with respect to the other histologic findings. Conclusions: Atherectomy specimens from patients with unstable angina demonstrated a trend toward increasing incidence of thrombus, but this trend did not achieve statistical significance. Specimens from patients with a recent myocardial infarction did not demonstrate a significant increase in the presence of thrombus. While thrombus is a component of the pathophysiology of unstable angina in a significant number of patients, continued study is required to determine the other factors that are responsible.