Sample topics in interventional cardiology from The Manual of Interventional Cardiology, followed by self-assessment questions from Interventional Cardiology: Self-Assessment and Review. The featured topic will be posted as a PDF file, which will automatically open via Adobe Acrobat. If you do not have Acrobat 4.0 or higher on your computer, click here to download it for free from the Adobe website. If you already have Acrobat on your computer, just click on the link to open the document. Once opened in Acrobat, the file can be saved, printed, or enlarged for better viewing. To return to our website, click on the "previous" arrow or button on your browser; do not close Acrobat by clicking on the "X" button in the upper right corner of the program.  Prior clinical modules are archived at the bottom of this page. MORE...

1. Which of the following statements about balloon angioplasty of long lesions are true:

a. Angioplasty success decreases as lesion length increases
b. Intravascular ultrasound has shown that residual stenosis is underestimated by contrast angiography, since the "normal" reference segment is often diseased
c. The relationship between lesion length and ischemic complications is controversial
d. All are true

Make your selection before scrolling beyond this point

Answer: Although angioplasty success declines as lesion length increases, procedural success can still be achieved in 74_97% of lesions > 20 mm in length. However, observational data may overestimate success rates since long lesions with other complex features (e.g, calcium, angulation) are often treated with laser, atherectomy devices, or stents. In the randomized Amsterdam Rotterdam (AMRO) trial of ELCA vs. PTCA for long lesions, PTCA success was only 79%. Furthermore, intravascular ultrasound has shown that the residual stenosis is frequently underestimated by contrast angioplasty since the "normal" reference segment used to measure stenosis severity is often diseased itself. The impact of lesion length on major complications is controversial. Several reports indicate that PTCA of long lesions is associated with an increased risk of dissection and abrupt closure. In these studies, the incidence of abrupt closure was 1-6% for lesions <10 mm and 9-14% for lesions > 10 mm. In contrast, other studies reported no relationship between lesion length and acute closure or major complications. These divergent results may be due to differences in patient characteristics, the presence of multivessel disease, associated lesion morphologies, and the use of long (30 - 40 mm) balloons and new devices. The influence of lesion length on restenosis risk is controversial. The Multi_Hospital Eastern Atlantic Restenosis Trial (M-HEART) demonstrated a direct relationship between lesion length and restenosis (lesion lengths of 0.3-2.9 mm, 3.0-4.6 mm, 4.7-7.0 mm, and 7.1-28.0 mm showed restenosis rates of 32%, 33%, 42%, and 49%, respectively). Other reports failed to demonstrate an association. Although long lesions may result in a greater loss in lumen diameter at 6-months, these observations do not necessarily correlate with clinical restenosis. Considerable clinical experience suggests that long (30-40 mm) balloons might improve acute results by distributing inflation pressure more evenly across the diseased vessel segment and atheroma/vessel junction, which is frequently the site of dissection. (Answer: d)

2. Which of the following statements about Rotablator atherectomy of long lesions are true:

a. Success and complication rates are independent of lesion length
b. Rotablator is the preferred method of revascularizing long lesions
c. When Rotablator is performed on long lesions, it is important to use slow passes and a small burr to minimize slow-flow and ischemic complications
d. All are true

Make your selection before scrolling beyond this point

Answer: Although early Rotablator success was possible in only 70% of long lesions, more recent studies have reported success in more than 90% of lesions 16-25 mm in length. However, increasing lesion length has been associated with an increased risk of MI, coronary artery perforation,and restenosis. Despite these complications, many interventionalists believe that Rotablator atherectomy (with adjunctive PTCA as needed) is the preferred method of revascularizing long lesions, especially those with superficial calcium. In such lesions, it is important to use slow passes with a small burr to minimize microcavitation and the generation of large particulate debris, which can result in slow-flow and ischemic complications. However, the preferred method for revascularizing long lesions has not been confirmed by any randomized trial. (Answer: c)

3. Compared to DCA of focal lesions, DCA of long lesions is associated with lower success, more ischemic complications, and higher restenosis rates:

a. True
b. False

Make your selection before scrolling beyond this point

Answer: In an early report by Robertson et al, DCA of long lesions resulted in lower success, more emergency CABG, and higher restenosis rates compared to DCA of focal stenoses. In another early report, lesion length independently predicted abrupt closure, which occurred in 3%, 4%, and 7% of lesions < 10 mm, 10-20 mm, and > 20 mm in length, respectively. In the CAVEAT trial, lesion length and calcification predicted DCA failure. More recently, Mooney et al. demonstrated procedural success in 97% of long lesions by making a series of longitudinal cuts through the entire length of the lesion; this allowed better DCA positioning (and less ischemia) during remaining circumferential cuts. Lesions were highly selected for favorable morphology; highly calcified or angulated lesions, and vessels < 3 mm in diameter were excluded. (Answer: a)

4. Which of the following statements about excimer laser coronary angioplasty (ELCA) of long lesions are false:

a. Procedural success is independent of lesion length
b. Dissections are more common in long lesions
c. In the Amsterdam-Rotterdam (AMRO) trial, ELCA resulted in higher procedural success and less restenosis than PTCA
d. In the Excimer Laser Rotablator Balloon Angioplasty for C-Lesions (ERBAC) trial, there was no difference in restenosis between ELCA, Rotablator, and PTCA at 6-months

Make your selection before scrolling beyond this point

Answer: In the first 3000 patients enrolled into the ELCA Registry, procedural success was 90% for short and long lesions. Importantly, procedural success was independent of lesion length and was achieved in 89% and 87% of lesions > 20 mm and > 30 mm in length, respectively. Although dissections were more common in long lesions, major ischemic complications occurred with equal frequency among short and long lesions. Randomized trials comparing ELCA vs. PTCA (AMRO trial), and ELCA vs. PTCA vs. Rotablator (ERBAC trial) for long lesions are now complete. In the AMsterdam ROtterdam (AMRO) trial, 308 patients with 325 lesions $ 10 mm were randomized to ELCA (without saline infusion) or balloon angioplasty. No differences in procedural success, late clinical events, or functional status were observed. However, ELCA was associated with more acute closure (8% vs. 0.8%, p = 0.005), a trend towards more restenosis (52% vs 41%, p = 0.13), and incremental costs of $4476 per treated segment. In the Excimer-Laser Rotablator Balloon Angioplasty for C-Lesions (ERBAC) trial, both ELCA and Rotablator resulted in better immediate lumen enlargement than PTCA, but no difference in restenosis at 6 months. The efficacy of ELCA for long lesions with heavy calcification, marked angulation, or thrombus awaits further study. (Answer: c)

5. Lesion length > 20 mm is a relative contraindication to stenting due to the increased risk of subacute thrombosis:

a. True
b. False

Make your selection before scrolling beyond this point

Answer: Lesions > 10-20 mm were excluded from the early stent experience since the use of multiple stents increased the risk of subacute stent thrombosis. Restenosis may be more common after stenting long lesions than short lesions, but the risk of subacute stent thrombosis is low. (Answer: b)

6. In the RAVEL and SIRIUS trials, the sirolimus-eluting stent resulted in lower restenosis rates compared to standard stents for focal and tubular lesions but not for long lesions:

a. True
b. False

Make your selection before scrolling beyond this point

Answer: In RAVEL, restenosis rates were lower with sirolimus stents for vessel diameters 2 mm (0% vs. 37%), 2.5 mm (0% vs. 21%), and 3.2 mm (0% vs. 20%). Likewise, preliminary results from SIRIUS indicate lower restenosis rates with sirolimus stents for vessel diameters 2.3 mm (8.8% vs. 23%), 2.8 mm (3.0% vs. 13.4%), and 3.25 mm (1.8% vs. 14.5%). (Answer: b)