Serial intravascular ultrasound analysis of bifurcation lesions treated using the novel self-expanding sideguard side branch stent.

We used intravascular ultrasound (IVUS) to assess the efficacy of the Cappella Sideguard stent system for treating coronary bifurcation lesions. Treatment of bifurcation lesions is associated with restenosis at the side branch (SB) ostium, presumably due to inadequate coverage or stent-vessel wall malapposition. To address these limitations, the Sideguard stent was developed. It includes a balloon-deployed, self-expanding, thin-strut, low-stress, nitinol bare metal stent with anatomic funnel-shaped flaring at the SB ostium. Of 25 patients enrolled in the Sideguard I First-In-Man study, complete serial (after intervention and 6-month follow-up) IVUS images were available in 11 patients. All patients were treated with (1) predilation of the SB, (2) Sideguard stenting in the SB, (3) Cypher stenting in the main vessel, and (4) kissing balloon inflations. The Sideguard stent area at the SB carina increased from 3.9 +/- 1.2 to 4.6 +/- 1.1 mm(2) (p = 0.04), resulting in no change in lumen area (3.9 +/- 1.3 vs 4.0 +/- 1.3 mm(2), p = 0.77) despite an intimal hyperplasia (IH) area of 0.6 +/- 0.7 mm(2). Six patients had minimal IH; the increase in stent area translated into an increase in lumen area of 0.4 +/- 0.6 mm(2); 5 patients had relatively more IH (1.3 +/- 0.4 mm(2)), but the increase in stent area of 1.3 +/- 0.3 mm(2) compensated for the IH, resulting in no lumen decrease. In contrast, the main vessel stent area at the carina did not change (5.9 +/- 1.1 vs 6.0 +/- 1.2 mm(2), p = 0.35). In conclusion, serial IVUS analyses of the self-expanding bare metal Sideguard stent indicate preserved SB ostial lumen dimensions at follow-up due to additional increases in stent area that more than compensated for IH.

Impact of gender and age on in vivo virtual histology-intravascular ultrasound imaging plaque characterization (from the global Virtual Histology Intravascular Ultrasound [VH-IVUS] registry).

Virtual histology intravascular ultrasound (VH-IVUS) analyses were performed in the first 990 patients enrolled in the 3,000+ patient global VH-IVUS Registry to assess the impact of gender and age on in vivo VH-IVUS plaque characterization. The 990 patients were divided into 3 age group terciles (<58, 58 to 68, and >68 years) and again divided according to gender. In conclusion, (1) both women and men had an increase in plaque with increasing age; (2) at any age, men had more plaque than women; (3) percentages of dense calcium and necrotic core increased with increasing patient age in both men and women; and (4) gender differences were lowest in the oldest tercile (>68 years).

Comparison of angiographic and intravascular ultrasonic detection of myocardial bridging of the left anterior descending coronary artery.

The purpose of this study was to determine the incidence, location, and clinical features of myocardial bridging (MB) detected by intravascular ultrasound (IVUS) and to compare IVUS-detectable versus angiographically detectable MBs. IVUS images were analyzed in 331 consecutive patients with de novo coronary lesions located in the left anterior descending coronary artery (LAD). MB was defined as a segment of coronary artery having systolic compression and echocardiographically lucent muscle surrounding the artery (IVUS) or systolic milking (angiography). Although angiography detected MB in only 3% of patients (11 of 331), 75 MB segments (23%, 75 of 331, p <0.001) were identified by IVUS. Maximum plaque burden within the MB segment measured only 25 +/- 7%, and abnormal intimal thickness (defined as >or=0.5 mm) was not observed within the bridged segment of any patient with MB, although the study population had advanced atherosclerosis. Vessel and lumen areas in the MB segment were significantly smaller than those in adjacent proximal and even distal reference segments. Angiographically detectable MB was significantly longer, located more proximally in the LAD, and had more severe systolic compression by IVUS. Angiographically silent MB more often occurred in the presence of an adjacent proximal stenosis and lower left ventricular ejection fraction. In conclusion, IVUS may provide useful anatomic information for the accurate diagnosis of MBs that are largely angiographically silent. IVUS-detectable MBs were observed in approximately 1/4 of patients undergoing LAD imaging at our center.