Kenya Nasu

Procedural and in-hospital outcomes after percutaneous coronary intervention for chronic total occlusions of coronary arteries 2002 to 2008: impact of novel guidewire techniques.

The aim of this study was to examine the procedural success and in-hospital outcomes after percutaneous coronary intervention (PCI) for chronic total occlusions in the current era during contemporary practice. The technique of PCI has improved over time with the introduction of novel equipment and guidewire crossing techniques. However, there is limited data available from contemporary practice in the recent years. We evaluated the procedural and in-hospital outcomes in a consecutive series of 904 procedures performed at Toyohashi Heart Center for PCI of chronic total occlusions of >3 months in duration. Technical and procedural success was achieved in 87.5% and 86.2%, respectively. In-hospital major adverse cardiac events occurred in only 1.9% of the patients. Single antegrade wire was the predominant strategy for guidewire crossing; however, retrograde guidewire crossing was used in 7.2% of the cases and controlled antegrade and retrograde subintimal tracking in 9.9% of the cases as the final strategy. Logistic regression analysis identified severe tortuosity and moderate-to-severe calcification as significant predictors of procedural failure. This is the first reported large series of patients undergoing PCI for chronic total occlusion with improved wire crossing techniques. We have reported high success rates in recent years and very low complication rates despite the use of more aggressive devices and techniques.

Retrograde Percutaneous Recanalization of Chronic Total Occlusion of the Coronary Arteries Procedural Outcomes and Predictors of Success in Contemporary Practice

Background— Retrograde approach through collaterals has been introduced for percutaneous recanalization of chronic total occlusion (CTO) of the coronary arteries. We investigated the safety and efficacy of retrograde approaches used for percutaneous recanalization of CTO in a consecutive series of patients. Methods and Results— We studied 157 consecutive patients who underwent retrograde CTO recanalization between 2003 and 2008 at a single center. A total of 118 (75.2%) of these patients have had previously failed antegrade attempts. Septal, epicardial, and saphenous vein graft collaterals were used in 67.5%, 24.8%, and 7.6% of cases, respectively. Collateral channel was crossed by guide wire successfully in 115 (73.2%) cases, and the procedure was successful by retrograde approach in 103 (65.6%) cases. Collateral channels (CCs) were graded as follows: CC0, no continuous connection; CC1, continuous thread-like connection; and CC2, continuous, small sidebranch-like connection. CC1, collateral tortuosity 90° ( P =0.0007), and nonvisibility of connection with recipient vessel were found to be significant predictors of procedural failure. The CC dissection was observed in 6 patients, with 1 needing coil embolization and others who were managed conservatively. The major adverse cardiac events were low, with 1 coronary artery bypass graft, 1 Q-wave myocardial infarction, 5 non–Q-wave myocardial infarctions, and no deaths in this group of patients. Conclusions— The retrograde approach in CTO percutaneous coronary intervention is effective in recanalizing CTO. The success rate by retrograde approach was 65.6%, and final success was 85% in this group with acceptable overall adverse events. We have identified predictors of failure related to collateral morphology. Received November 28, 2008; accepted February 13, 2009. # CLINICAL PERSPECTIVE {#article-title-2}Background—Retrograde approach through collaterals has been introduced for percutaneous recanalization of chronic total occlusion (CTO) of the coronary arteries. We investigated the safety and efficacy of retrograde approaches used for percutaneous recanalization of CTO in a consecutive series of patients. Methods and Results—We studied 157 consecutive patients who underwent retrograde CTO recanalization between 2003 and 2008 at a single center. A total of 118 (75.2%) of these patients have had previously failed antegrade attempts. Septal, epicardial, and saphenous vein graft collaterals were used in 67.5%, 24.8%, and 7.6% of cases, respectively. Collateral channel was crossed by guide wire successfully in 115 (73.2%) cases, and the procedure was successful by retrograde approach in 103 (65.6%) cases. Collateral channels (CCs) were graded as follows: CC0, no continuous connection; CC1, continuous thread-like connection; and CC2, continuous, small sidebranch-like connection. CC1, collateral tortuosity <90°, and angle with recipient vessel <90° (P<0.0001) were significant predictors of success. Epicardial channel use (P=0.01), CC0, corkscrew channel (P<0.0001), angle with recipient vessel >90° (P=0.0007), and nonvisibility of connection with recipient vessel were found to be significant predictors of procedural failure. The CC dissection was observed in 6 patients, with 1 needing coil embolization and others who were managed conservatively. The major adverse cardiac events were low, with 1 coronary artery bypass graft, 1 Q-wave myocardial infarction, 5 non–Q-wave myocardial infarctions, and no deaths in this group of patients. Conclusions—The retrograde approach in CTO percutaneous coronary intervention is effective in recanalizing CTO. The success rate by retrograde approach was 65.6%, and final success was 85% in this group with acceptable overall adverse events. We have identified predictors of failure related to collateral morphology.

Coronary septal collaterals as an access for the retrograde approach in the percutaneous treatment of coronary chronic total occlusions.

Objectives: To investigate the feasibility and safety of the percutaneous dilatation of coronary septal collaterals and to allow its use as an access for retrograde approach to percutaneous coronary intervention (PCI) of coronary chronic total occlusions (CTOs). Background: Despite improvements in percutaneous techniques and materials, CTO recanalization success rate is still suboptimal. The retrograde approach allows to significantly increase this success rate. However, its application via a bypass graft or epicardial collateral can potentially result in severe complications. A safer retrograde access is desired and would allow broadening the application of the retrograde approach in the percutaneous treatment of CTOs. Methods: After a failed antegrade CTO recanalization attempt, a retrograde approach via septal collaterals was tried in 21 patients (19 males, 2 females). The septal collateral was accessed via the contralateral patent coronary artery and was crossed with a hydrophilic floppy wire. After successful wire crossing of the septal collateral, sequential low pressure dilatation was performed with a 1.25 or 1.5 mm balloon to allow the delivery of a balloon catheter up to the distal CTO site. Results: Successful wire crossing and balloon dilatation of septal collaterals was achieved in 19 cases and in 17 cases, respectively. Postdilatation septal collateral diameter increased significantly reaching a mean diameter of 1.46 ± 0.38 mm. Retrograde CTO recanalization was successfully performed in 71% of the cases. No major complications occurred. Conclusions: Coronary septal collaterals can be used as an access for the retrograde approach in the percutaneous treatment of CTOs.

The efficacy of a bilateral approach for treating lesions with chronic total occlusions the CART (controlled antegrade and retrograde subintimal tracking) registry.

OBJECTIVES The aim of this study was to evaluate the safety and feasibility of a new concept for chronic total occlusion (CTO) recanalization-using a bilateral approach that utilizes a Controlled Antegrade and Retrograde subintimal Tracking (CART) technique. BACKGROUND Successful percutaneous recanalization of coronary CTOs results in improved long-term outcomes. The recanalization of CTOs in native coronary arteries no doubt represents one of the most technically challenging of interventional procedures. METHODS A total of 224 consecutive patients (mean age 61 +/- 9 years; 86.2% men) were enrolled in this prospective multicenter registry. This technique combines the simultaneous use of antegrade and retrograde approaches. A subintimal dissection is created in both antegrade and retrograde fashion, thereby limiting the extension of the subintimal dissection within the CTO portion. RESULTS Of 224 CTO lesions (>3 months in duration) undergoing attempted recanalization using the CART technique, 145 cases (64.7%) had undergone previous CTO recanalization attempts. The success rates of crossing in a retrograde fashion with a wire and a balloon were 87.9% and 79.9%, respectively. The overall technical and procedural success rates achieved in this registry were 92.4% and 90.6%, respectively. CONCLUSIONS A bilateral approach for CTO lesions using the CART technique is feasible, safe, and has a higher success rate than previous approaches. These results indicate that a bilateral technique can solve a major dilemma that commonly affects CTO procedures.

The First Clinical Experience With a Novel Catheter for Collateral Channel Tracking in Retrograde Approach for Chronic Coronary Total Occlusions

OBJECTIVES The aim of this study was to report the initial experience with a novel catheter in the retrograde approach for chronic total occlusion (CTO). BACKGROUND Although the use of the retrograde approach in percutaneous coronary intervention for CTO has been established, some procedural difficulties remain. METHODS A novel over-the-wire catheter (channel dilator) specifically designed for the retrograde approach has been developed for the treatment of CTO. The channel dilator was used in 93 CTO lesions after successful wiring of collateral channels using the retrograde approach. RESULTS Successful channel crossing of the catheter was achieved in 90 of the lesions (96.8%), and the channel dilator successfully advanced into the occlusion reversely during retrograde wiring in 85 lesions (94.4%). Of the 75 lesions with successful advancement of the retrograde wire into the proximal true lumen, the entire occlusion was crossed retrograde with the channel dilator in 63 lesions (84.0%). To evaluate the feasibility of the catheter, 93 CTO lesions in the preceding period were compared. Procedure and fluoroscopy time tended to be lower in the study group than in the control group. The success of the retrograde procedure was significantly higher in the study group than in the control group (98.9% vs. 92.5%, p = 0.030). CONCLUSIONS The channel dilator may facilitate the conventional retrograde approach with a high level of success.

Effect of fluvastatin on progression of coronary atherosclerotic plaque evaluated by virtual histology intravascular ultrasound.

OBJECTIVES The aim of this study was to evaluate the effect of treatment with statins on the progression of coronary atherosclerotic plaques of a nonculprit vessel by serial volumetric virtual histology (VH) intravascular ultrasound (IVUS). BACKGROUND Recent clinical trials have demonstrated a reduction of atherosclerotic plaque, yet whether statin therapy affects the change in components of plaque remains unknown. METHODS This study was a nonrandomized and nonblinded design. Eighty patients with stable angina pectoris were divided into either the fluvastatin group (n = 40) or the control group (n = 40) according to their total or low-density lipoprotein (LDL) cholesterol level. The volume of each plaque component (dense calcium, fibrous tissue, fibro-fatty, or necrotic core) was evaluated at baseline and at 12-month follow-up. RESULTS The LDL cholesterol and high-sensitivity C-reactive protein (hsCRP) levels in the fluvastatin group were significantly decreased at time of follow-up. In VH IVUS findings, fibro-fatty volume was significantly decreased (baseline 80.1 +/- 57.9 mm(3) vs. follow-up 32.5 +/- 27.7 mm(3), p < 0.0001) and fibrous tissue volume was increased (baseline 146.5 +/- 85.6 mm(3) vs. follow-up 163.3 +/- 94.5 mm(3), p < 0.0001) in the fluvastatin group. In the control group, the volumes of all plaque components without fibrous tissue were significantly increased. Change in fibro-fatty volume has a significant correlation with a change in LDL cholesterol level (R = 0.703, p < 0.0001) and change in hsCRP level (R = 0.357, p = 0.006). CONCLUSIONS One-year lipid-lowering therapy by fluvastatin showed significant regression of plaque volume and alterations in atherosclerotic plaque composition with a significant reduction of fibro-fatty volume.

Plaque characterisation by Virtual Histology intravascular ultrasound analysis in patients with type 2 diabetes

Objectives: To evaluate the in-vivo plaque composition and characteristics in patients with type 2 diabetes mellitus (DM) using Virtual Histology intravascular ultrasound (VH IVUS). Methods: In 90 patients with stable angina pectoris, de novo target vessels were studied and plaque components were analysed. Patients were divided into two groups: a diabetic group (36 vessels) and a non-diabetic group (54 vessels). Results: The percentage area of necrotic core and dense calcium were significantly larger in the DM group than the non-DM group (necrotic core: 11.0% (interquartile range (IQR): 7.2–15.2%) vs 7.6% (IQR 5.6–13.2%), p = 0.03; dense calcium: 5.6% (IQR: 2.3–7.3%) vs 2.9% (IQR: 1.7–4.9%), p = 0.01). The DM group presented with a significantly higher presence of at least one VH IVUS-derived thin-cap fibroatheroma (VHD-TCFA) (75% vs 41%, p = 0.001) and VH IVUS-derived fibrocalcific atheroma (VHD-FCA) (75% vs 40%, p = 0.001). In the DM group, 53% of the vessels had both VHD-TCFA and VHD-FCA, which was significantly higher than non-DM group (17%, p = 0.0004). Conclusions: Coronary plaque characteristics in DM patients showed an increased amount of dense calcium and necrotic core, as well as a higher frequency of VHD-TCFA and VHD-FCA. Atherosclerosis of the target vessel was more advanced in diabetic patients.

Predictors of angiographic restenosis after drug eluting stents in the coronary arteries: contemporary practice in real world patients

AIMS Drug eluting stents (DES) have been used routinely in a wide variety of clinical situations. The impact of DES on reducing restenosis has not been uniform across complex subsets and limited data is available examining predictors of restenosis in unselected population. METHODS AND RESULTS We investigated predictors of angiographic restenosis in an unselected population. The study population consisted of 4,143 lesions and angiographic follow-up was available for 3,020 (73%) lesions in 1,885 patients. The intravascular ultrasound (IVUS) was used in 95% of the patients during the procedure. Angiographic restenosis was seen in 339 (11.2%) lesions and target lesion revascularisation was performed in 290 (9.6%) lesions. The patient population included large numbers of renal failure patients on haemodialysis, ISR, and Type C lesions with routine use of intravascular ultrasound. We identified diabetes mellitus, renal failure, Type C lesions, calcified lesion, tortuous lesion, ISR, long lesion, small baseline diameter and final vessel diameter as predictors of restenosis. On multivariate analysis diabetes (OR 1.45, 95% CI 1.07-1.97, p= 0.01), renal failure on haemodialysis (OR 2.02, 95% CI 1.37-3.27, p=0.001), ISR (OR 3.56, 95% CI 2.16-5.89, P<0.001), lesion length (OR 1.02, CI 1.01-1.03.P<0.001), reference vessel diameter (OR 0.50, 95% CI 0.31-0.80, p=0.005) and post-intervention IVUS lumen area (p<0.001) were independent predictors of angiographic restenosis. Female gender (OR 0.61, 95% CI 0.410.91, p=0.015) was found to have a negative correlation for ISR. We did not find any significant difference in restenosis between the usage of sirolimus and paclitaxel eluting stents. CONCLUSIONS DES usage was associated with overall low in-stent restenosis and we have identified several clinical, angiographic, and IVUS predictors of angiographic restenosis in unselected patients with complex anatomy.

Impact of Frequency-Domain Optical Coherence Tomography Guidance for Optimal Coronary Stent Implantation in Comparison With Intravascular Ultrasound Guidance

Background— Frequency-domain optical coherence tomography (FD-OCT) is a novel, high resolution intravascular imaging modality. Intravascular ultrasound (IVUS) is a widely used conventional imaging modality for achieving optimal stent deployment. The aim of this study was to evaluate the impact of FD-OCT guidance for coronary stent implantation compared with IVUS guidance. Methods and Results— A total of 70 patients with de novo coronary artery lesions and either unstable or stable angina pectoris were enrolled in this randomized study (optical coherence tomography [OCT] group: n=35, IVUS group: n=35). In the OCT group, stent implantation was performed under FD-OCT guidance alone and final stent expansion was evaluated by IVUS. In the IVUS group, conventional IVUS guidance was used and final stent apposition was evaluated by FD-OCT. There were no significant differences regarding the procedural, fluoroscopy time, and contrast volume. Although device and clinical success rates also were similar, the visibility of vessel border was significantly lower in the OCT group (P<0.05). Minimum and mean stent area and focal and diffuse stent expansion were smaller (6.1±2.2 mm versus 7.1±2.1 mm, 7.5±2.5 versus 8.7±2.4 mm, 64.7±13.7% versus 80.3±13.4%, 84.2±15.8% versus 98.8±16.5%, P<0.05, respectively), and the frequency of significant residual reference segment stenosis at the proximal edge was higher in the OCT group (P<0.05). Incomplete apposed struts in both groups were similar (P=0.34). Conclusions— FD-OCT guidance for stent implantation was associated with smaller stent expansion and more frequent significant residual reference segment stenosis compared with conventional IVUS guidance.

Rotational atherectomy for fibro‐calcific coronary artery disease in drug eluting stent era: Procedural outcomes and angiographic follow‐up results

Objectives: The aim of this study was to examine the binary re‐stenosis rates, procedural success, and in hospital outcomes following treatment of fibro‐calcified coronary lesion with rotational atherectomy in drug eluting stent era. Background: Binary restenosis rates have remained high with the use of bare metal stents following rotational atherectomy in calcified lesions. There is limited data available following rotational atherectomy in drug eluting stent era. Methods: We evaluated the procedural and angiographic outcomes following a consecutive series of 516 procedures treated with rotational atherectomy followed by stenting. We compared the results between Rota + Drug eluting stent (DES) and Rota + bare metal stent (BMS) groups. Results: Procedural success was achieved in 97.1% of the lesions with overall low in hospital adverse events (death in 1.1%, Q MI in 1.3%, Non Q MI in 5.3%, and urgent repeat PCI in 0.4%). There was significant reduction in the binary restenosis rates following Rota + DES use as compared to Rota + BMS use (11% vs. 28.1%, P < 0.001; OR = 3.17, 95% CI: 1.76–5.93) and similar reduction was seen in the target lesion revascularization (10.6% vs. 25%, P = 0.001; OR = 2.81, 95% CI: 1.53–5.14). We have identified ostial lesions, chronic total occlusion lesions, and use of bare metal stents as independent predictors of restenosis in this group of patients. Conclusions: Rotational atherectomy can be performed with high success rates and low complications, and rotational atherectomy followed by drug eluting stent implantation significantly reduces binary restenosis rates in fibrocalcific lesions as compared to rotational atherectomy and bare metal stents.