Iatrogenic left main coronary artery stenosis following PTCA or valve replacement

Late proximal coronary artery stenosis complicating percutaneous endovascular catheterisation procedures

BACKGROUND

Late-onset proximal coronary artery stenosis caused by preceding percutaneous catheterisation procedures remains under-surveyed.

METHODS

From 1993, all patients undergoing percutaneous coronary procedures and a second session within 3 years were included except those ever treated by coronary bypass surgery or chest radiotherapy during this 3-year period. Emergence of a new lesion or worsening of an initially insignificant lesion to >50% of diameter stenosis at the never-treated ostial/proximal coronary segment on the follow-up angiogram was defined as late coronary stenosis caused by the previous catheterisation procedure and was analysed.

RESULTS

From January 1993 to December 2005, 3240 patients who underwent 5025 procedures met the inclusion criteria. Of them, 23 patients experienced an event of late coronary artery stenosis (overall incidence 0.46%), and interventional procedures, specifically shaped catheters (Voda, XB, Amplatz Left) and atherosclerosis vulnerability correlated with risks of adverse events. Most of these events could be managed by contemporary medical, interventional, or surgical strategies, yet hazards of mortality and long-term restenosis still existed from this catheter-induced complication.

CONCLUSIONS

Percutaneous catheterisation procedures could be complicated by late proximal coronary artery stenosis. Thus, when conducting these procedures, operators should select and manipulate catheters with caution, especially in patients with susceptible clinical characteristics.

An unusual case of left internal mammary artery ostial disease: clarifying role of intravascular ultrasound

Stenosis at the origin of the left internal mammary artery graft is rare. We present a case with a suspected stenosis involving the origin of the left internal mammary artery that conventional angiography failed to demonstrate convincingly. Intravascular ultrasound illustrated a severe stenosis and the patient underwent successful stenting of the left internal mammary artery origin. The intravascular ultrasound finding of a dissection flap, just distal to the left internal mammary artery origin, suggests that local trauma to the vessel from prior catheterization procedures may have been responsible for the progressive narrowing at the left internal mammary artery ostium.

Iatrogenic coronary artery stenosis following coronary stenting

We present 6-month follow-up of 435 patients undergoing stent deployment. Forty-four patients were referred because of myocardial ischemia related to the stented artery. In six of these patients (14%), the stented vessel revealed a new proximal lesion separated from the stented portion, which warranted further intervention. It is felt that these new lesions are related to the stenting technique as a result of local trauma induced from the guiding catheter.

Arterial remodeling at the reference site after angioplasty in the atherosclerotic rabbit model

Recent studies suggest that arterial remodeling plays an important role in restenosis and that remodeling at the reference site may also occur. To assess the chronic effect of the reference site remodeling on angioplasty results, we evaluated reference site remodeling in an experimental atherosclerotic restenosis model. Histological sections of iliac stenoses and their associated proximal reference segments from 50 atherosclerotic rabbits killed 4 weeks after angioplasty were analyzed. Lumen area (LA), external elastic lamina area (EEL), and intimal plus medial areas (I+M) were measured at the lesion (L) and reference (R) sites. Angiography was performed preangioplasty, immediately postangioplasty, and 4 weeks postangioplasty. Restenosis was defined as an angiographic loss/gain ratio of greater than 50% at follow-up angiography. Twenty-three lesions were restenotic (R+) and 32 were not (R-). There was no difference in reference site diameters (RD) between these two groups at the time of angioplasty. However, RDs were significantly smaller in the R+ group than in the R- group (1.24+/-0.18 versus 1.52+/-0.28 mm, n=55, P<.01) at 4-week follow-up. Morphometric analysis also showed a smaller LA(R) in the R+ group (0.85+/-0.27 versus 1.06+/-0.37 mm2, n=55, P<.02), whereas there was no difference in I+M(R) between the two groups. EEL(R) significantly correlated with EEL(L), LA(R), and I+M(R) in both groups combined (r=.53, n=55, P<.0001; r=.62, n = 55, P < .0001; and r = .86, n = 55, P < .0001, respectively). Remodeling can favorably and unfavorably affect both the lesion and the reference sites and appears to occur in parallel and proportionately at both sites. These data suggest that angiographic measurement of late percent stenosis using reference site diameters may lead to an underestimation of the percent luminal narrowing in restenotic lesions because unfavorable remodeling occurs in both the lesion and reference sites in restenotic vessels.

Giant left main coronary artery aneurysm in association with severe atherosclerotic coronary disease

Aneurysms of the coronary arteries occur in 1.5-4.9% of coronary angiograms. Only a few cases of a giant aneurysm of the left main coronary artery in conjunction with severe atherosclerotic coronary disease have been reported. This report details the exceptional case of a 72-year-old patient with a giant "true saccular" aneurysm branched on the left main coronary artery. The development of an aneurysmal dilatation in conjunction with progression of coronary arteriosclerosis, observed from two different angiographic studies at an interval of 25 years, is very illustrative for evolutive atherosclerotic heart disease. This finding may support the hypothesis that atherosclerosis may be the common etiology for coronary aneurysmal dilatation.

Subacute narrowing of the left main coronary artery following directional atherectomy for proximal obstructive coronary artery disease

Directional atherectomy is an alternative device for treatment of highly eccentric or proximal coronary lesions considered less suitable for balloon angioplasty. We report a patient with exuberant neointimal proliferation, extending into the left main coronary artery, following directional atherectomy of the proximal target site in the left circumflex artery. This observation indicates that patients with mild left main disease have an increased risk to develop this complication following directional atherectomy.

Subacute bilateral coronary ostial stenoses following cardiac catheterization and PTCA

Accelerated coronary ostial stenosis is an infrequent late complication of coronary artery catheter instrumentation during aortic valve surgery, PTCA, or coronary angiography. We report the first case of bilateral coronary artery ostial stenoses developing after cardiac catheterization and right coronary artery PTCA. In patients with worsening angina following cardiac catheterization or PTCA, accelerated ostial stenoses should not be over-looked in the differential diagnosis.

Coronary artery aneurysm formation following percutaneous transluminal coronary angioplasty: treatment of associated restenosis with repeat percutaneous transluminal coronary angioplasty

Restenosis following coronary angioplasty can usually be treated effectively and safely by repeated angioplasty. However, the presence of a complex lesion morphology may bias the clinician away from angioplasty toward either recommending bypass surgery or continuing medical therapy alone in spite of recurrence of the symptoms which were sufficient indication for the initial angioplasty. One type of complex morphology at the site of the restenosis is due to the presence of a focal, eccentric aneurysmal dilatation similar in appearance to a saccular aneurysm. In two previously reported cases in the literature both were referred to bypass surgery. We report eight additional cases including the use of repeat successful angioplasty in six of the cases in spite of the potential problems posed by the complexity of the restenosed lesion. In addition, this case review suggests that this type of complex lesion morphology with restenosis may be more common when the initial angioplasty was associated with deep arterial injury, as in patients whose initial angioplasty was done in an infarct-related vessel or was associated with evidence of a large dissection.

Progression of left main coronary artery stenosis following left anterior descending coronary artery angioplasty

Although recent clinical experience indicates a high success rate, percutaneous transluminal coronary angioplasty (PTCA) is still associated with serious complications which usually occur during or shortly after the procedure and are principally related to the lesion or segment of vessel being dilated. We report 2 cases of subacute progression within months of left main stenosis following successful, uncomplicated left anterior descending (LAD) coronary PTCA. Identification of left main trunk involvement may mandate earlier follow-up or intervention.

Unpredictable cause of early recurrence of angina pectoris after successful double coronary angioplasty

Early recurrence of symptoms after successful coronary angioplasty is usually due to restenosis of the angioplasty site. Multilesion progression of atherosclerosis in the presence of patent prior dilated segments has not, to our knowledge, been reported as a cause of early recurrent angina after successful double coronary angioplasty. As both new lesions were also successfully dilated, this case demonstrates that multivessel coronary angioplasty is a repeatedly effective and patient-friendly procedure to treat symptomatic coronary atherosclerosis with rapid and unpredictable rate of progression.

Left main coronary artery dissection during percutaneous transluminal coronary angioplasty

Acute dissection of the left main coronary artery during diagnostic cardiac catheterization with selective coronary arteriography is an uncommon but recognized complication of the procedure. That similar dissection may occur during percutaneous transluminal coronary angioplasty is less well recognized. This report describes two cases of left main coronary dissection resulting in acute occlusion that occurred during percutaneous transluminal coronary angioplasty and demonstrates that survival with essentially complete functional recovery may result if immediate surgical intervention is undertaken. Recognition and treatment of this potentially catastrophic complication of angioplasty is described.