Acute outcome of directional coronary atherectomy vs standard balloon angioplasty in de novo left anterior descending stenoses

Influence of stenotic lesion morphology on immediate and long-term (6 months) angiographic outcome: comparative analysis of directional coronary atherectomy versus standard balloon angioplasty

OBJECTIVES

This study sought to determine whether preprocedural lesion morphology differentially affects the outcome of directional coronary atherectomy versus standard balloon angioplasty.

BACKGROUND

Despite previous studies (Canadian Coronary Atherectomy Trial [CCAT]/Coronary Angioplasty Verus Excisional Atherectomy Trial [CAVEAT]), directional coronary atherectomy continues to be recommended on the basis of lesion-specific features, although the validity of this approach has never been proved.

METHODS

A retrospective, subgroup analysis of the CCAT data base (group average +/- SD) was performed.

RESULTS

In the long term (6 months), both procedures were equally successful in the proximal left anterior descending coronary artery (directional atherectomy 0.62 +/- 0.70 mm vs. coronary angioplasty 0.70 +/- 0.72 mm, p = NS), with atherectomy tending to perform best in relatively "simple" lesions (American College of Cardiology/American Heart Association [ACC/AHA] type A: atherectomy 0.57 +/- 0.70 mm vs. angioplasty 0.50 +/- 0.77 mm; ACC/AHA type B1: atherectomy 0.65 +/- 0.68 mm vs. angioplasty 0.60 +/- 0.68 mm) and those with moderate dystrophic calcification (atherectomy 0.79 +/- 0.56 mm vs. angioplasty 0.45 +/- 0.73 mm). Although greatest minimal lumen diameter gains were seen in larger (> 3 mm) coronary arteries (atherectomy 0.76 +/- 0.62 mm vs angioplasty 0.80 +/- 0.72 mm, p = NS) and those with severe obstruction (preprocedural minimal lumen diameter < 1.0 mm: atherectomy 0.80 +/- 0.62 mm vs. angioplasty 0.84 +/- 0.63 mm, p = NS), neither technique was superior, and eccentric stenoses (symmetry index < 0.5) had similar outcomes (atherectomy 0.59 +/- 0.49 mm vs. angioplasty 0.62 +/- 0.65 mm, p = NS).

CONCLUSIONS

These data refute many preconceptions regarding the choice of directional coronary atherectomy on the basis of anatomic criteria.

Directional coronary atherectomy for lesions of the proximal left anterior descending artery: initial clinical results, complications and histopathological findings

BACKGROUND

Directional coronary atherectomy is a percutaneous technique which extends the role of balloon angioplasty to bulky eccentric coronary lesions.

AIMS

To report the early experience, clinical results, complications and histopathological findings of directional coronary atherectomy (DCA) in proximal left anterior descending artery (LAD) stenosis.

METHODS

Study of 25 lesions in 24 patients on whom directional atherectomy was performed on the proximal LAD artery with the Simpson coronary atherectomy device.

RESULTS

Twenty-five procedures were performed on 24 patients with stenosis in the proximal LAD artery. There were 21 males and three females with a mean age of 56.5 years. Sixteen patients presented with stable angina and eight with unstable angina. Eight patients had previous myocardial infarction (MI). Angiographic success was obtained in 24 of 25 lesions (96%). The mean lesion length was 13.1 +/- 3.7 mm and the mean LAD artery diameter was 3.6 +/- 0.5 mm. Minimal luminal diameter improved from 0.9 +/- 0.4 mm to 3.0 +/- 0.5 mm and the percentage diameter stenosis reduced from 75 +/- 12% to 16 +/- 9%. Complications included acute occlusion in one patient, non-Q MI in three patients, local vascular complications in one patient and side-branch loss in one patient. Histology demonstrated fibrous cap of atherosclerotic plaque in 100%, media and internal elastic lamina in 28% and intimal hyperplasia in 100% of restenotic lesions and 27% of native lesions. Restenosis rates in angiographically restudied patients was 27%. The mean minimal luminal diameter at follow-up was 2.3 +/- 0.9 mm and the mean percentage diameter stenosis was 35 +/- 21%.

CONCLUSION

From this initial study, we conclude that DCA is an effective and safe procedure for the treatment of large proximal LAD lesions. DCA provides a large luminal diameter and "smoother' angiographic appearance compared to coronary angioplasty. Acute complication rates are low and restenosis rates were comparable with percutaneous transluminal coronary balloon angioplasty.

Primary directional coronary atherectomy for acute myocardial infarction

The effectiveness of primary coronary angioplasty for acute myocardial infarction (AMI) is now widely recognized. However, the reocclusion rate is as high as 10%. Directional coronary atherectomy (DCA), now used widely in the treatment of stable and unstable angina pectoris, has not been recommended as the primary reperfusion therapy for AMI. This report describes the first preliminary study of primary DCA for AMI without any antecedent thrombolytic therapy or balloon coronary angioplasty. Five patients received primary DCA. The initial results were very good, but further study is necessary to determine the efficacy, particularly the long-term results, of primary DCA in the treatment of AMI.

Early experience of directional coronary atherectomy: clinical results, complications and histopathological findings

OBJECTIVE

To report the early experience, clinical results and histopathologic findings of Directional Coronary Atherectomy from a UK centre experienced in coronary angioplasty.

DESIGN

Prospective study of the first 45 Directional Coronary Atherectomy (DCA) procedures using the Simpson coronary atherectomy device.

RESULTS

Forty-five procedures were performed in 33 male and 5 female patients (mean age, 55.1 years). Directional Coronary Atherectomy was performed to 50 lesions (39 de novo, 11 restenosis; 44 left anterior descending, 3 right, 2 circumflex coronary arteries and 1 saphenous vein graft). Clinical and primary angiographic success was achieved in 43 of 45 cases (95.5%) and in 47 of 50 lesions (94%) after DCA alone. Before DCA the mean diameter stenosis was 88.7% (range, 50-100%) but following DCA (and percutaneous coronary angioplasty (PTCA) if necessary) the mean diameter stenosis was 3.5% (range, 0-15%; P < 0.001). Complications included occlusive dissection requiring coronary artery bypass surgery in two patients; abrupt closure of right coronary artery in one patient successfully reopened by PTCA and thrombolysis, complicated by excessive blood loss; reversible coronary artery spasm due to minor nose-cone trauma in four patients and temporary side branch loss in one patient. There were no coronary artery perforations, guide catheter complications, peripheral vascular trauma or deaths. On average 5.6 specimens (range, 1-18) were removed per case. Histology showed fibrous intimal plaque in 98%, media in 39% and adventitia in 7%. Neo-intimal hyperplasia was found in all restenosis lesions but also in 30% of de novo lesions.

CONCLUSIONS

This small initial series indicates that directional coronary atherectomy is an effective and safe procedure for the treatment of obstructive coronary artery disease in carefully selected patients. With care, a high success rate can be achieved even during a learning phase. The technique is particularly effective for morphologically complex lesions that are unfavourable for PTCA. The procedure is unlike PTCA and requires additional training if pitfalls are to be avoided, high success rates achieved and complication rates kept low.

A comparison of directional atherectomy with balloon angioplasty for lesions of the left anterior descending coronary artery

BACKGROUND

Restenosis is a major limitation of coronary angioplasty. Directional coronary atherectomy was developed with the expectation that it would provide better results than angioplasty, including a lower rate of restenosis. We undertook a randomized, multicenter trial to compare the rates of restenosis for atherectomy and angioplasty when used to treat lesions of the proximal left anterior descending coronary artery.

METHODS

Of 274 patients referred for first-time, non-surgical revascularization of lesions of the proximal left anterior descending coronary artery, 138 were randomly assigned to undergo atherectomy and 136 to undergo angioplasty; 257 of 265 eligible patients (97 percent) underwent follow-up angiography at a median of 5.9 months. Computer-assisted quantitative measurements of luminal dimensions were determined from the angiograms obtained before and immediately after the procedure and at follow-up. The primary end point of restenosis was defined as stenosis of more than 50 percent of the vessel's diameter at follow-up.

RESULTS

Quantitative analysis showed that the procedural success rate was higher in patients who underwent atherectomy than in those who had angioplasty (94 percent vs. 88 percent, P = 0.061); there was no significant difference in the frequency of major in-hospital complications (5 percent vs. 6 percent). At follow-up, the rate of restenosis was 46 percent after atherectomy and 43 percent after angioplasty (P = 0.71). Despite a larger initial gain in the minimal luminal diameter with atherectomy (mean [+/- SD], 1.45 +/- 0.47 vs. 1.16 +/- 0.44 mm; P < 0.001), there was a larger late loss (0.79 +/- 0.61 vs. 0.47 +/- 0.64 mm; P < 0.001), resulting in a similar minimal luminal diameter in the two groups at follow-up (1.55 +/- 0.60 vs. 1.61 +/- 0.68, P = 0.44). The clinical outcomes at six months were not significantly different between the two groups.

CONCLUSIONS

The role of atherectomy in percutaneous coronary revascularization remains to be fully defined. However, as compared with angioplasty, atherectomy did not result in better late angiographic or clinical outcomes in patients with lesions of the proximal left anterior descending coronary artery.