Indications and Outcomes
Each atherectomy device has a specific set of indications. Rotational atherectomy is the most common atherectomy procedure and is used to treat complex lesions and in-stent restenosis. Directional atherectomy is used rather infrequently but is useful for treating non-calcific ostial lesions. Orbital atherectomy has not been used extensively since it is a new procedure and TEC has fallen out of favor among cardiologists.
The indications for the use of rotational atherectomy vary between centers and physicians. Atherectomy can prove useful for particularly difficult lesions and in cases where stenting and angioplasty are not appropriate. According to a multi-center study published in 2004, 24% of rotational atherectomy procedures were for in-stent restenosis. The remaining 74% of rotational atherectomies were for complex lesions.
In-stent restenosis refers to the redevelopment of plaque after the implantation of a stent. This condition is difficult to treat since the stent cannot be removed. Rotational atherectomy is sometimes used to treat this condition. Rotational atherectomy is useful for in-stent restenosis when:
The other application of rotational atherectomy is for complex lesions that cannot be suitably treated with angioplasty or stents. The lesions include:
Atherectomy can also prove very useful when used before stent placement or angioplasty. Removing atherosclerotic plaque before these procedures relieves stress applied to the artery walls when the plaque in compacted.
The 2004 multi-center study found a 94% rate of procedural success for the use of rotational atherectomy. This means that an appropriate luminal diameter was obtained and there were no related complications. In the unsuccessful cases, death occurred in 1.4% of procedures. Major adverse cardiac events (MACE) represented 4.5% of cases. Device failure occurred in 2 cases (<1%).
At 9-month follow-up, about half the patients suffered no complications and passed a stress-test. Among other patients complications ranged from MACE (17.3%) to recurrent angina (25.2%) and death in three cases (1.1%).
The results show that rotational atherectomy can prove very useful in difficult cases and in cases of in-stent restonosis. Unfortunately, the 9-month success rates are not as high as hoped. In addition, other studies have found that the use of rotational to balloon angioplasty in cases of in-stent restenosis.
The indications for directional atherectomy are more limited and the use of directional atherectomy has mostly fallen out of favor. Some of the possible indications of directional atherectomy include:
Since directional atherectomy is used so infrequently, no recent studies of its efficacy have been performed. Directional atherectomy will remain a useful tool in the cardiologist’s arsenal, especially for non-calcified ostial lesions.
Atherectomy procedures are not recommended for:
Other devices in use each have their own indications and personal preferences among physicians. Rotational atherectomy currently remains the atherectomy procedure of choice among most interventional cardiologists. Indications for new atherectomy devices such as orbital atherectomy must still be developed since trials are currently underway. The results from these trials are promising. Some of these new procedures appear to provide improved performance over the currently preferred rotational procedure.
The TEC (transluminal extraction catheter) is used to remove plaque buildup in vascular grafts used in coronary artery bypass graft surgery. Saphenous vein grafts often develop atherosclerotic lesions similar to those found in native coronary arteries. Atherectomy can be a helpful tool in removing this plaque to avoid re-operation. Unfortunately, the TEC device is not used frequently since it tends to damage the vessel wall.
Atherectomy can be used to treat peripheral atherosclerotic lesions. Especially successful is the use of rotational atherectomy to treat these lesions in the legs. The use of atherectomy to treat stenosed carotid arteries has been considered but the risk of brain damage or stroke is considered too high.