Standardized volumetric plaque quantification and characterization from coronary CT angiography: a head-to-head comparison with invasive intravascular ultrasound.

OBJECTIVES: We sought to evaluate the accuracy of standardized total plaque volume (TPV) measurement and low-density non-calcified plaque (LDNCP) assessment from coronary CT angiography (CTA) in comparison with intravascular ultrasound (IVUS). METHODS: We analyzed 118 plaques without extensive calcifications from 77 consecutive patients who underwent CTA prior to IVUS. CTA TPV was measured with semi-automated software comparing both scan-specific (automatically derived from scan) and fixed attenuation thresholds. From CTA, %LDNCP was calculated voxels below multiple LDNCP thresholds (30, 45, 60, 75, and 90 Hounsfield units [HU]) within the plaque. On IVUS, the lipid-rich component was identified by echo attenuation, and its size was measured using attenuation score (summed score ∕ analysis length) based on attenuation arc (1 = < 90°; 2 = 90-180°; 3 = 180-270°; 4 = 270-360°) every 1 mm. RESULTS: TPV was highly correlated between CTA using scan-specific thresholds and IVUS (r = 0.943, p < 0.001), with no significant difference (2.6 mm3, p = 0.270). These relationships persisted for calcification patterns (maximal IVUS calcium arc of 0°, < 90°, or ≥ 90°). The fixed thresholds underestimated TPV (- 22.0 mm3, p < 0.001) and had an inferior correlation with IVUS (p < 0.001) compared with scan-specific thresholds. A 45-HU cutoff yielded the best diagnostic performance for identification of lipid-rich component, with an area under the curve of 0.878 vs. 0.840 for < 30 HU (p = 0.023), and corresponding %LDNCP resulted in the strongest correlation with the lipid-rich component size (r = 0.691, p < 0.001). CONCLUSIONS: Standardized noninvasive plaque quantification from CTA using scan-specific thresholds correlates highly with IVUS. Use of a < 45-HU threshold for LDNCP quantification improves lipid-rich plaque assessment from CTA. KEY POINTS: • Standardized scan-specific threshold-based plaque quantification from coronary CT angiography provides an accurate total plaque volume measurement compared with intravascular ultrasound. • Attenuation histogram-based low-density non-calcified plaque quantification can improve lipid-rich plaque assessment from coronary CT angiography.

First reported revascularization of complex occlusion of the right coronary artery using the IVUS-guided reverse CART technique via a gastroepiploic artery graft.

When patients who have previously undergone coronary artery bypass graft surgery develop ischemia symptoms that cannot be controlled by optimal medical therapy, repeat revascularization is indicated. The revascularization strategy should be based on individual clinical and anatomical characteristics. We report here a challenging patient who presented with recurrent stable angina due to worsening of a proximal right coronary artery (RCA) stenosis to chronic total occlusion (CTO) after anastomosis of the right gastroepiploic artery (GEA) to the posterior descending artery. A soft guidewire was advanced through the right GEA collateral channel to the distal end of the CTO, but the dedicated CTO guidewires could not be advanced across the severely calcified CTO using the retrograde wire crossing or kissing wire techniques. The RCA was eventually revascularized by implantation of drug-eluting stents using the intravascular ultrasound-guided reverse controlled antegrade and retrograde subintimal tracking technique.

Percutaneous intervention in a patient with a rare single coronary artery from the left coronary sinus of valsava.

A single coronary artery (SCA) arising from the sinus of Valsalva and supplying the entire heart is a rare congenital anomaly. According to modified Lipton's classification, L-1 subtype is a most rare type of SCA. We presented a case classified as L-I subtype, in which initially left main divided into the left anterior descending and circumflex arteries normally; then, the second septal artery proceeded as the proximal right coronary artery, the distal circumflex artery proceeded as the middle and distal right coronary artery. The patient finally underwent percutaneous intervention in the left anterior descending artery owing to a stable angina.

Long-Term (>10 Years) clinical outcomes of first-in-human biodegradable poly-l-lactic acid coronary stents: Igaki-Tamai stents.

BACKGROUND: The purpose of this study was to evaluate the long-term safety of the Igaki-Tamai stent, the first-in-human fully biodegradable coronary stent made of poly-l-lactic acid. METHODS AND RESULTS: Between September 1998 and April 2000, 50 patients with 63 lesions were treated electively with 84 Igaki-Tamai stents. Overall clinical follow-up (>10 years) of major adverse cardiac events and rates of scaffold thrombosis was analyzed together with the results of angiography and intravascular ultrasound. Major adverse cardiac events included all-cause death, nonfatal myocardial infarction, and target lesion revascularization/target vessel revascularization. During the overall clinical follow-up period (121 ± 17 months), 2 patients were lost to follow-up. There were 1 cardiac death, 6 noncardiac deaths, and 4 myocardial infarctions. Survival rates free of all-cause death, cardiac death, and major adverse cardiac events at 10 years were 87%, 98%, and 50%, respectively. The cumulative rates of target lesion revascularization (target vessel revascularization) were 16% (16%) at 1 year, 18% (22%) at 5 years, and 28% (38%) at 10 years. Two definite scaffold thromboses (1 subacute, 1 very late) were recorded. The latter case was related to a sirolimus-eluting stent, which was implanted for a lesion proximal to an Igaki-Tamai stent. From the analysis of intravascular ultrasound data, the stent struts mostly disappeared within 3 years. The external elastic membrane area and stent area did not change. CONCLUSION: Acceptable major adverse cardiac events and scaffold thrombosis rates without stent recoil and vessel remodeling suggested the long-term safety of the Igaki-Tamai stent.

Successful bypass restenting across the struts of an occluded subintimal stent in chronic total occlusion using a retrograde approach.

Recently, subintimal angioplasty has been introduced as a bailout strategy to improve the success rate of PCI for vessels with CTO. However, the long-term outcome of subintimal angioplasty has not been determined, and a limitation of subintimal angioplasty is the uncertainty in making the re-entry point. We report two cases, where occlusive in-stent restenosis occurred in a stent implanted in the subintimal space of the RCA that had CTO. These two cases were successfully treated with bypass restenting across the struts of an occluded subintimal stent using a retrograde approach. A retrograde wire crossed the occluded segment through the lumen along the outside of the stent and reentered the inside of the stent across the stent struts. The reverse CART technique followed by multiple restenting across the stent struts restored antegrade flow. Follow-up angiography demonstrated the patency of the RCA.

Approach for chronic total occlusion with intravascular ultrasound-guided reverse controlled antegrade and retrograde tracking technique: single center experience.

BACKGROUND: Controlled antegrade and retrograde subintimal tracking (CART) or reverse CART techniques is the final step for percutaneous revascularization of coronary chronic total occlusion (CTO), but it still represents technical challenges and risk in interventional procedures. OBJECTIVES: Our purpose was to utilize intravascular ultrasound (IVUS)-guided reverse CART approach for percutaneous revascularization of CTO in our heart center, focusing on its safety, efficacy, and latest technical developments. METHODS: From November 2006 to November 2012, 49 patients with CTO failed to antegrade and/or retrograde percutaneous revascularization of CTO from true lumen to true lumen were enrolled in and underwent IVUS guided reverse CART approach. RESULTS: The mean J-CTO score of cases was 2.5. IVUS guidance was successfully implemented in 95.9%; IVUS identified that 61.7% of retrograde wires were located at intimal space, and 59.5% of antegrade wires were located at subintimal space. A Corsair channel dilator was used in 77.6% of cases. The success rates of technique and procedure were 95.9% and 93.9%, respectively; the technical minor complications were observed in 10.2% of cases, without significant clinic outcomes; 2.0% of cases occurred with a major adverse cardiac event of non-ST-elevation myocardial infarction; and no case occurred with target vessel revascularization or death. The mean length of stent implanted in a single CTO vessel was 51.3 mm. No patient appeared with radiation dermatitis and contrast-induced rise of creatinine. CONCLUSIONS: IVUS guided reverse CART approach is effective and safe for percutaneous revascularization of complex CTO, with a high success and a low complication rate. It is feasible to develop this approach for percutaneous revascularization of complex CTO. However, suitable case selection and lately device handling by experienced operators are the crucial points of success.

Comparison of haemodialysis patients and non-haemodialysis patients with respect to clinical characteristics and 3-year clinical outcomes after sirolimus-eluting stent implantation: insights from the Japan multi-centre post-marketing surveillance registry.

AIMS: Long-term outcomes after sirolimus-eluting stent (SES) implantation in haemodialysis (HD) patients have remained controversial. We investigated the impact of HD on outcomes after SES implantation. METHODS AND RESULTS: We analysed the data on 2050 patients who underwent SES implantation in a multi-centre prospective registry in Japan. Three-year clinical outcomes were compared between the HD group (n = 106) and the non-haemodialysis (NH) group (n = 1944). At the 3-year clinical follow-up, the rates of unadjusted cardiac mortality (HD: 16.3 vs. NH: 2.3%) and target-lesion revascularization (TLR) (HD: 19.4 vs. NH: 6.6%) were significantly higher in the HD group than the NH group (P < 0.001). Although HD group had a numerically higher stent thrombosis rate, the difference in stent thrombosis between the two groups (HD: 2.0 vs. NH: 0.7%) did not reach statistical significance. Using Cox's proportional-hazard models with propensity score adjustment for baseline differences, the HD group had higher risks of TLR [HD: 16.3 vs. NH: 6.1%; hazard ratio, 2.83; 95% confidence interval (CI): 1.62-4.93, P = 0.0003] and cardiac death (HD: 12.3 vs. NH: 2.3%; hazard ratio, 5.51; 95% CI: 2.58-11.78, P < 0.0001). The consistent results of analyses, whether unadjusted or adjusted for other baseline clinical and procedural differences, identify HD as an independent risk factor for cardiac death and TLR. CONCLUSIONS: Percutaneous coronary intervention with SES in HD patients has a higher incidence of repeat revascularization and mortality compared with those in NH patients. Haemodialysis appears to be strongly associated with mortality and repeat revascularization even after SES implantation.

Clinical and angiographic outcomes with sirolimus-eluting stent for coronary bifurcation lesions. The J-PMS study.

BACKGROUND: Long-term outcomes of patients with bifurcated lesions and the restenotic response of the side branches after sirolimus-eluting stent (SES) implantation, comparing 1-stent with 2-stent treatment, are still under discussion. METHODS AND RESULTS: Japan Post-Marketing Surveillance Registry (J-PMS) is a prospective registry designed to evaluate the safety and efficacy of the SES in routine clinical practice. Angiograms of 1,063 patients with 1,250 lesions were analyzed at the independent core lab. Of these, 324 patients with bifurcation lesions were enrolled. Clinical endpoints were assessed at 3 years. Both main and side branches were evaluated by quantitative coronary angiography at post-procedure (n=349) and 8-month follow up (n=293). Two-stent treatment was performed in 12% of the cases. In-segment restenosis rates at 8 months were 25.6% in the side branch, but newly developed restenosis was seen in only 6.8%. Late loss at the carina of the side branch was -0.11mm in the 1-stent group. Major adverse cardiovascular events rate was 18.3% at 3 years. Target-lesion revascularization rate up to 3 years was 21.6% in the 2-stent group and 8.7% in the 1-stent group (P=0.037). Stent thrombosis occurred in 6 cases (2.0%) until 3 years. Of these, 4 cases were treated with 2-stent (10.81% vs. 0.76% in 1-stent, P=0.003, respectively). CONCLUSIONS: In a real-world setting, treatment of coronary bifurcation lesions using SES demonstrated favorable long-term outcomes as long as the side branch was not stented.

Effect of Transluminal Injection of Foam Sclerotherapy Combined with Endovenous Thermal Ablation of Varicose Veins.

OBJECTIVE: The combination of endovenous therapies with stab avulsion or ultrasound guided foam sclerotherapy is widely performed. However, these conventional techniques tend to result in incomplete avulsions or persistent varicosities. METHODS: One hundred and thirteen legs in 97 consecutive patients who underwent 1470 nm laser ablation for great saphenous varicose veins were enrolled. The foam sclerosing agent was injected via the sheath after endovenous laser ablation (EVLA). Patients were divided into two groups: EVLA only group (Control; n = 50) and EVLA and transluminal injection of foam sclerotherapy (TLFS) group (SCL; n = 63). RESULTS: At three month follow up, reflux was abolished throughout all treated great saphenous veins (GSVs) when assessed with Duplex ultrasound. Thrombophlebitis was observed in two patients in the SCL group (p = .13). Additional second stage sclerotherapy was needed in the Control group (n = 33, 66%) vs. SCL group (n = 2, 3%; p < .0001). The venous clinical severity score (VCSS) was significantly improved in the SCL group (changes of VCSS, Control -3.3 ± 1.7 and SCL -4.4 ± 1.0; p < .0001). Univariable and multivariable analyses revealed that, among age, sex, Clinical-Etiology-Anatomy-Pathophysiology classification, linear endovenous energy density, and TLFS, TLFS was the only significant factor of improved VCSS (hazard ratio = -0.96; 95% confidence interval = -1.4 to -0.58; p < .0001). CONCLUSIONS: TLFS combined with EVLA may be an easy, safe, and effective procedure with acceptable complications vs. EVLA alone and reduces additional second stage interventions.

A case of recurrent varicose veins due to the multiple fistulas from superficial femoral artery.

Recurrent varicose veins are considered to be caused by the recurrence of reflux but rarely may be secondary to other pathologies. A 39-year-old man complained of right lower leg skin pigmentation, pain and fatigue for several years. Duplex ultrasound revealed that the great saphenous vein diameter at the saphenofemoral junction level was 7.7 cm, and at the knee medial level was 14.4 cm. The reflux time at the proximal great saphenousvein level was 1.85 s. Endovenous laser ablation for dilated and refluxed great saphenous vein was performed. However, 1 year later, the symptoms recurred. Duplex ultrasound suspected abnormal arterial flow from the right superficial femoral artery to the recanalized segment of previously ablated great saphenous vein and anterior accessory saphenous vein. One month later, despite the successful re-endovenous laser ablation, the symptoms recurred. Computed tomography angiography showed three fistulous vessels from superficial femoral artery to anterior accessory saphenous vein. Combined treatments with endovenous laser ablation and coil embolization was performed. Ultimately, the fistulas were obliterated and the patient remained free of symptoms. Varicose veins due to the fistulas from superficial femoral artery are rare and difficult to diagnose but can be entirely treated with the percutaneous approach.

Traditional antegrade approach versus combined antegrade and retrograde approach in the percutaneous treatment of coronary chronic total occlusions.

OBJECTIVES: The goal of this study was to compare the antegrade-approach and bilateral-approach strategies for chronic total occlusion (CTO). BACKGROUND: The retrograde approach has been reported for difficult CTO lesions. METHODS: This study assessed 96 consecutive patients with 119 CTO lesions. The lesions were treated with either an antegrade approach (A group) or a combined bilateral antegrade and retrograde approach (B group). The specific intervention techniques, in-hospital success rate, and major adverse cardiac and cerebrovascular events (MACCE) were compared. RESULTS: Lesions with well-developed septal collaterals with nontortuous microchannels were preferentially chosen for the B group versus A group (P < 0.001 and 0.008, respectively). Compared with the A group, there were more CTO lesions located in the right coronary artery in the B group (P < 0.001). In the B group, the CTO lesions had a longer length and needed stiffer wires for crossing than in the A group (P = 0.001 and 0.046, respectively). The technical success rate was 94% and 86% for the A group and the B group, respectively (P = 0.127). In-hospital complications were not different between the two groups. The B group needed a higher radiation exposure dose and a greater exposure time than the A group (P < 0.001). In the B group, use of the retrograde method significantly increased the final success rate. CONCLUSIONS: These results suggest that all CTO lesions should first be managed with an antegrade approach. When there is difficulty crossing the lesion, switching to a bilateral approach is an option for lesions with well-developed collaterals.

Improved Evaluation of Lipid-Rich Plaque at Coronary CT Angiography: Head-to-Head Comparison with Intravascular US.

PURPOSE: To improve the evaluation of low-attenuation plaque (LAP) by using semiautomated software and to assess whether the use of a proposed automated function (LAP editor) that excludes voxels adjacent to the outer vessel wall improves the relationship between LAP and the presence and size of the lipid-rich component (LRC) verified at intravascular US. At coronary CT angiography, quantification of LAP can improve risk stratification. Plaque, defined as the area between the vessel and the lumen wall, is prone to partial volume effects from the surrounding pericoronary adipose tissue. MATERIALS AND METHODS: The percentage of LAP (%LAP), defined as the percentage of noncalcified plaque with an attenuation value lower than 30 HU (LAP/total plaque volume) at greater than or equal to 0 mm (%LAP0), greater than or equal to 0.1 mm (%LAP0.1), greater than or equal to 0.3 mm (%LAP0.3), greater than or equal to 0.5 mm (%LAP0.5), and greater than or equal to 0.7 mm (%LAP0.7) inward from the vessel wall boundaries, were quantified in 155 plaques in 90 patients who underwent coronary CT angiography before intravascular US. At intravascular US, the LRC was identified by using echo attenuation, and its size was measured by using the attenuation score (summed score/analysis length) based on the attenuation arc (1 = < 90°, 2 = 90° to < 180°, 3 = 180° to < 270°, 4 = 270°-360°) for every 1 mm. RESULTS: Use of LAP editing improved the ability for discriminating LRC (areas under receiver operating characteristic curve: 0.667 with %LAP0, 0.713 with %LAP0.1 [P < .001 for comparison with %LAP0]), 0.778 with %LAP0.3 [P < .001], 0.825 with %LAP0.5 [P < .001], 0.802 with %LAP0.7 [P = .002]). %LAP0.5 had the strongest correlation (r = 0.612, P < .001) with LRC size, whereas %LAP0 resulted in the weakest correlation (r = 0.307; P < .001). CONCLUSION: Evaluation of LAP at coronary CT angiography can be significantly improved by excluding voxels that are adjacent to the vessel wall boundaries by 0.5 mm.Supplemental material is available for this article.© RSNA, 2019.

Effect of tube potential and luminal contrast attenuation on atherosclerotic plaque attenuation by coronary CT angiography: In vivo comparison with intravascular ultrasound.

BACKGROUND: It has been shown that CT attenuation of noncalcified plaques depends on luminal contrast attenuation (LCA). Although tube potential (kilovolt [kV]) has been shown to exert influence on plaque attenuation through LCA as well as its direct effects, in-vivo studies have not investigated plaque attenuation at lower tube potentials less than 120 kV. We sought to evaluate the effect of kV and LCA on thresholds for lipid-rich and fibrous plaques as defined by intravascular ultrasound (IVUS). METHODS: CT attenuation of IVUS-defined plaque components (lipid-rich, fibrous, and calcified plaques) were quantified in 52 consecutive patients with unstable angina, who had coronary CT angiography performed at 100 kV (n = 25) or 120 kV (n = 27) using kV-adjusted contrast protocol prior to IVUS. CT attenuation of plaque components was compared between the two groups. RESULTS: LCA was similar in the 100-kV and 120-kV groups (417.6 ±â€¯83.7 Hounsfield Units [HU] vs 421.3 ±â€¯54.9 HU, p = 0.77). LCA correlated with CT attenuation of lipid-rich (r = 0.49, p = 0.001) and fibrous plaques (r = 0.32, p < 0.05), but not with that of calcified plaques (r = 0.04, p = 0.81). When plaque attenuation was normalized to LCA, lipid-rich (0.087 ±â€¯0.036, range -0.012-0.147) and fibrous plaque attenuation (0.234 ±â€¯0.056, range 0.153-0.394) were distinct (p < 0.001) with no overlap for both kV groups. CT attenuation was not significantly different between 100-kV and 120-kV groups for lipid-rich (34.0 ±â€¯21.5 vs 39.3 ±â€¯12.9, p = 0.33) or fibrous plaques (95.4 ±â€¯19.1 vs 97.6 ±â€¯22.0, p = 0.75). CONCLUSION: Plaque attenuation thresholds for non-calcified plaque components should be adjusted based on LCA. Further adjustment may not be required for different tube potentials.

CVIT expert consensus document on primary percutaneous coronary intervention (PCI) for acute myocardial infarction (AMI) in 2018.

While primary percutaneous coronary intervention (PCI) has significantly contributed to improve the mortality in patients with ST segment elevation myocardial infarction even in cardiogenic shock, primary PCI is a standard of care in most of Japanese institutions. Whereas there are high numbers of available facilities providing primary PCI in Japan, there are no clear guidelines focusing on procedural aspect of the standardized care. Whilst updated guidelines for the management of acute myocardial infarction were recently published by European Society of Cardiology, the following major changes are indicated; (1) radial access and drug-eluting stent over bare metal stent were recommended as Class I indication, and (2) complete revascularization before hospital discharge (either immediate or staged) is now considered as Class IIa recommendation. Although the primary PCI is consistently recommended in recent and previous guidelines, the device lag from Europe, the frequent usage of coronary imaging modalities in Japan, and the difference in available medical therapy or mechanical support may prevent direct application of European guidelines to Japanese population. The Task Force on Primary Percutaneous Coronary Intervention of the Japanese Association of Cardiovascular Intervention and Therapeutics (CVIT) has now proposed the expert consensus document for the management of acute myocardial infarction focusing on procedural aspect of primary PCI.

Incidence and impact on midterm outcome of intimal versus subintimal tracking with both antegrade and retrograde approaches in patients with successful recanalisation of chronic total occlusions: J-PROCTOR 2 study.

AIMS: The aim of this study was to assess the incidence and impact on midterm outcomes of intimal versus subintimal tracking with both antegrade and retrograde approaches in patients undergoing successful percutaneous coronary intervention for chronic total occlusion (CTO). METHODS AND RESULTS: In 2012, a total of 1,573 CTO cases from 30 hospitals were enrolled in the Japanese CTO registry. Successful guidewire crossing was performed in 1,411 cases (89.7%). Among them, the guidewire penetration position was clearly identified using intravascular ultrasound (IVUS) imaging in 352 cases, and clinical follow-up at 12 months was performed in 323 cases. These 323 cases were enrolled in this retrospective study: 242 cases were treated with the antegrade approach (antegrade group) and 81 cases were treated with the retrograde approach (retrograde group). The endpoint of this study was target vessel revascularisation (TVR) and major adverse cardiac events (MACE) at 12-month follow-up. Subintimal tracking occurred more frequently in the retrograde group (11.6% vs. 30.9%, p<0.01). TVR was more frequent in the subintimal tracking group in the retrograde group (7.1% vs. 16.0%, p=0.03) but not in the antegrade group (2.8% vs. 3.6%, p=0.99). Although the occlusion length was similar, the subintimal tracking group required a longer stent length compared to the intimal tracking group in the retrograde approach (59.7±24.4 mm vs. 74.0±24.4 mm, p<0.01). CONCLUSIONS: Subintimal tracking was more frequent in the retrograde approach. Intimal tracking should be recommended in the retrograde approach to reduce stent length and to improve follow-up outcomes.

Serial angioscopic findings after successful intracoronary brachytherapy for in-stent restenosis.

The intracoronary changes that occur after brachytherapy for in-stent restenosis (ISR) have yet to be fully established. The purpose of this study in patients who had ISR was to examine the serial angioscopic changes in intracoronary lesions that occurred after brachytherapy. Forty-four patients who had ISR (49 lesions) underwent balloon angioplasty (n = 34) or directional atherectomy (n = 15), followed by intracoronary brachytherapy using a beta-emitting phosphorus-32 source wire. Angioscopic investigations were performed 3 and 9 months after brachytherapy. Uncovered stents were detected in 63.3% of lesions at 3 months. A significant decrease (p = 0.028) in this prevalence occurred over the next 6 months, with 36% of lesions having uncovered stents at 9 months. At 3 months, 33% of the lesions had visible erosion or ulceration and superficial thrombus. The prevalence of these characteristics was decreased at 9 months, although 17% of the lesions were still ulcerated or eroded at that time. Protruding thrombus was not observed in any lesion at 3 and 9 months. In conclusion, uncovered stents and intimal erosions or ulcerations were still present 9 months after brachytherapy in 36% and 17% of lesions, respectively. These results suggest that the healing process was not completed 9 months after brachytherapy in approximately 33% of lesions.

Current Retrograde Approach Is Unfavorable to Long-Term Clinical Outcomes after Percutaneous Coronary Intervention for Chronic Total Occlusion.

Surgeons currently use two different wire-based approaches to recanalize coronary chronic total occlusion (CTO): antegrade and retrograde. It has been demonstrated that the retrograde approach has improved the procedural success rate, but it remains unclear whether the retrograde approach is better than the antegrade approach for the long term. In this study, we enrolled a total of 187 patients with a diagnosis of CTOs. We evaluated the baseline characteristics of these patients and performed percutaneous coronary intervention to treat their problems by using either antegrade or retrograde approaches and different techniques in both groups. In the antegrade approach, we used three techniques: single wire, parallel wire, and side branch. The techniques in retrograde included kissing wire, controlled antegrade and retrograde subintimal tracking (CART), and reverse CART. We found that the antegrade and retrograde groups had similar baseline characteristics, with a few minor differences. Most importantly, we found that within 1 yr of the recanalizing procedure, the restenosis rate and major adverse cardiac event rate of the retrograde group were significantly higher compared to the antegrade group. We conclude that the retrograde approach may not be as beneficial as the antegrade approach for long-term clinical outcomes.

Frequency and time course of reocclusion and restenosis in coronary artery occlusions after balloon angioplasty versus Wiktor stent implantation: results from the Mayo-Japan Investigation for Chronic Total Occlusion (MAJIC) trial.

BACKGROUND: Compared with balloon angioplasty, stent implantation has been shown to reduce restenosis and reocclusion after treatment of chronic total coronary artery occlusions (CTOs). However, little is known about the time course of restenosis and reocclusion after the 2 procedures. The purpose of this study was to examine the frequency and time course of restenosis and reocclusion after treatment of CTOs with balloon angioplasty and Wiktor stent implantation. METHODS AND RESULTS: A total of 221 patients with successfully recanalized CTOs were randomly assigned to either treatment with a coil stent implantation (Wiktor stent, n = 110) or standard balloon angioplasty (n = 111). Repeat angiography was performed the day after treatment and at 6 months. Patients undergoing balloon angioplasty showed 29.8% restenosis and 1.1% reocclusion the following day versus 2% restenosis and no reocclusion in stent patients the following day. The cumulative reocclusion rate was significantly lower in the stent group than in the balloon group at 6 months (2.1% versus 9.3%, P <.05). As a result of the more frequent need of target vessel revascularization (49.5% in the balloon group and 30.6% in the stent group, P <.005) and earlier final follow-up angiography in the balloon group, the frequency of angiographic restenosis at 6 months was similar in both groups (57.3% in the stent group and 54.5% in the balloon group). CONCLUSIONS: The frequency and time course of reocclusion and restenosis after balloon angioplasty and stent placement differ within 24 hours of the procedure and remain different on angiography at 6 months.

Intravascular ultrasound-guided directional coronary atherectomy for unprotected left main coronary stenoses with distal bifurcation involvement.

Stent implantation in unprotected left main coronary artery (LMCA) bifurcation lesions may improve procedural and late clinical outcomes. However, concerns regarding stent-related complications, such as stent jail, subacute thrombosis, and in-stent restenosis remain. Optimal debulking by directional coronary atherectomy (DCA) with intravascular ultrasound (IVUS) guidance may be effective in this complex lesion subset, but this strategy has not yet been established. Our objective was to evaluate the safety and efficacy of IVUS-guided DCA for unprotected LMCA stenoses with distal bifurcation involvement. A total of 67 consecutive patients were included in this study and procedural success was achieved in all cases. Two cardiac deaths (2.9%) were noted and 3 patients (4.5%) underwent repeat angioplasty during hospitalization. There was no Q-wave myocardial infarction or emergency bypass surgery. Non-Q-wave myocardial infarction (creatine kinase-MB >3 times normal) occurred in 13.4% of patients. Stent implantation was necessary in 17 cases (25.4%) to achieve an optimal result. IVUS showed an improved lumen cross-sectional area and a low plaque burden in the LMCA after intervention. All-cause mortality, angiographic restenosis, and the target lesion revascularization rates at 6 months were 7.4%, 23.8%, and 20.0%, respectively. With IVUS guidance, aggressive DCA can be performed safely in unprotected LMCA bifurcation lesions, and optimal angiographic and IVUS results can be achieved with low residual plaque burden, which leads to a low restenosis rate. Optimal lesion debulking by DCA does not necessarily need adjunctive stenting in this specific anatomic subset.