Angioscopic Evaluation of Vascular Response After Fluoropolymer-Based Drug-Eluting Stent Implantation for Femoropopliteal Artery Lesions.

BACKGROUND: Although favorable clinical outcomes have been demonstrated for fluoropolymer-based paclitaxel-eluting stents (FP-DES) in the treatment of femoropopliteal lesions, the vascular response after implantation has not been systematically studied through intravascular imaging.Methods and Results: We angioscopically compared FP-DES: 24 in the early phase (mean [±SD] 3±1 months), 26 in the middle phase (12±3 months), and 20 in the late phase (≥18 months) after implantation. The dominant neointimal coverage grade, heterogeneity of neointimal coverage grade, and thrombus adhesion in the stent segment were evaluated. Neointimal coverage was graded as follows: Grade 0, stent struts exposed; Grade 1, struts bulging into the lumen, although covered; Grade 2, struts embedded in the neointima, but visible; Grade 3, struts fully embedded and invisible. Dominant neointimal coverage and heterogeneity grades were significantly higher in the middle and late phases than in the early phase (all P<0.05), but did not differ significantly between the middle and late phases. The incidence of thrombus adhesion was recorded for all stents in each of the 3 different phases. CONCLUSIONS: The middle and late phases after FP-DES implantation were associated with significantly higher dominant neointimal coverage and heterogeneity grades than the early phase. However, thrombus adhesion was observed in all phases after FP-DES implantation. Arterial healing may not be completed even in the late phase after FP-DES implantation.

Influence of catheter ablation for atrial fibrillation on atrial and ventricular functional mitral regurgitation.

AIMS: The purpose of this study was to compare the impact of catheter ablation on cardiac structural reverse remodelling and atrial (AFMR) and ventricular (VFMR) functional mitral regurgitation (MR), and the long-term prognosis of patients with AFMR and VFMR. METHODS AND RESULTS: The retrospective study included persistent AF patients who had AFMR (n = 136, left atrial (LA) volume index >30 mL/m2 and left ventricular (LV) ejection fraction ≥40%) or VFMR (n = 31, LV ejection fraction <40% or LV regional asynergy) and had undergone the initial AF ablation from April 2015 to December 2019. Baseline and 6 month follow-up echocardiography were performed to assess MR, LA, and LV sizes. MR improvement after ablation was comparable in the AFMR (64%) and VFMR groups (52%, P = 0.20). Patients with AFMR improvement showed a greater decrease in left atrial volume after ablation than those without (amount of change: -11.4 ± 15.1 vs. -2.3 ± 21.1 mL/m2 , P = 0.01). Patients with VFMR improvement showed a greater increase in LV ejection fraction than those without (amount of change: 28.5 ± 13.6% vs. 9.0 ± 14.8%, P = 0.001). The composite endpoint of all-cause death and heart failure hospitalization during the 2 year follow-up period was more frequently observed in the VFMR than in the AFMR group (22.6% vs. 3.7%, P < 0.0001). Patients with MR improvement after catheter ablation less frequently demonstrated the composite endpoint than those without (1.9% vs. 15.6%, P < 0.0001). CONCLUSIONS: Atrial functional mitral regurgitation and VFMR improvement after ablation were associated with atrial and ventricular reverse remodelling, respectively. It is possible that long-term prognosis is better in patients with AFMR than with VFMR, and in those with MR improvement than in those without.

Safety, efficacy, and cost-performance of a simplified cryoballoon ablation procedure for paroxysmal atrial fibrillation.

BACKGROUND: The search for a less invasive and lower cost cryoballoon-based strategy for atrial fibrillation (AF) ablation has resulted in a simplified procedure that may be suitable for cryoballoon ablation (CBA). Here, we compared procedural characteristics and outcomes between conventional CBA and simple CBA. METHODS: We enrolled 628 consecutive patients who underwent initial CBA for AF (age, 69 ± 12 years; female, 263 (42%); paroxysmal AF, 576 (92%); CHA2DS2-VASc score, 2.7 ± 1.6 points). Simple CBA was characterized by the minimal procedure required to isolate pulmonary veins, including the following: (1) CBA was performed without guidance from a 3-D mapping system; (2) a coronary sinus electrode and esophageal temperature probe were not used; (3) a waiting period after pulmonary vein isolation was not set; and AF induction by isoproterenol and atrial burst stimuli were not performed. RESULTS: Simple CBA was performed in 240 (38%) patients. Procedural time (49 ± 18 versus 85 ± 27 min, p < 0.01) was shorter, and total procedural costs (20,699 ± 8,091 versus 30,350 ± 11,647 US dollars, p < 0.01) were lower with simple CBA than conventional CBA. Freedom from AF recurrence during the 12-month study period (79.8% versus 78.4%, p = 0.52) and complication rate (8.8% versus 13.1%, p = 0.09) were similar between the two groups. CONCLUSION: Compared with conventional CBA, simple CBA reduced procedural time and procedural costs while providing comparable outcomes.

Saphenous vein size as a surrogate marker for mortality of patients with chronic limb-threatening ischemia undergoing endovascular therapy.

BACKGROUND: The size of the autologous vein graft is an important determinant of prognosis in patients with chronic limb-threatening ischemia (CLTI) undergoing bypass surgery. However, it is unclear whether reconstruction using a small vein graft would directly affect prognosis, or a subgroup having small veins would be subject to a poor prognosis. If the latter is true, having small veins would work as a marker for a poor prognosis even in patients with CLTI undergoing endovascular therapy (EVT). Therefore, we investigated the association between the size of saphenous veins and prognosis in patients with CLTI undergoing EVT. METHODS: This study included 209 consecutive patients with CLTI who primarily underwent EVT between January 2017 and December 2018. The diameter of the saphenous vein was measured at three locations (saphenous-femoral junction, knee, and ankle joint) per limb before EVT by ultrasonography. A small saphenous vein was defined as the mean diameter <3.0 mm. RESULTS: All-cause mortality rate was significantly higher in patients with a small saphenous vein than in those with non-small one (46.3% versus 10.7% at 2 years, p<0.001). The multivariate Cox regression analysis revealed that a small saphenous vein was independently associated with an increased risk of all-cause mortality. CONCLUSIONS: Having a small saphenous vein was an independent marker for all-cause mortality in patients with CLTI undergoing EVT.

Improved crossability with novel cutting balloon versus scoring balloon in the treatment of calcified lesion.

Cutting balloons and scoring balloons are commonly used for the preparation of calcified lesion. However, problems with crossability occasionally limit the use of cutting balloons. We prospectively selected 173 calcified lesions treated using a novel cutting balloon (Wolverine™, C group). As control, we retrospectively analyzed 146 calcified lesions treated using a scoring balloon (Lacrosse NSE ALPHA™, S group). Either intravascular ultrasound (IVUS) or optical coherence tomography (OCT) was used by the operator's discretion. The primary outcome was delivery success, which was defined as successful passage to the target lesion immediately after IVUS or OCT evaluation. The secondary outcome was acute cross-sectional area (CSA) gain, which was defined as post-interventional minimum stent area minus pre-procedural minimum lumen area. A multivariate analysis evaluated the independent predictors for delivery success. The delivery success rate was significantly higher in the C group versus the S group (90.8% versus 79.5%, P = 0.006). However, the acute CSA gain was similar between the two groups (IVUS: 3.2 ± 1.8 mm2 versus 3.4 ± 1.9 mm2, P = 0.53; OCT: 3.6 ± 1.4 mm2 versus 4.1 ± 1.9 mm2, P = 0.11). Usage of cutting balloon was an independent predictor for delivery success even after the adjustment for the patient and lesion characteristics [odds ratio (OR): 2.72 (95% confidence interval 1.38-5.33), P = 0.004] as well as the procedural characteristics [OR: 2.34 (1.15-4.86), P = 0.018]. Novel cutting balloons demonstrated better crossability and similar acute CSA gain compared with scoring balloons in calcified lesion.

Angioscopic assessments and clinical outcomes one year after polymer-free biolimus A9-coated coronary stent implantation.

BACKGROUND: Polymer-free biolimus A9-coated coronary stent (DCS) has novel features which lead to the expectation of better arterial healing. However, comparisons of intravascular status between DCS and drug-eluting stents (DES), and robust real-word clinical assessments of DCS have been lacking to date. METHODS: From September 2017 to September 2018, we evaluated the intra-vascular status of 74 DCS implanted in 55 lesions from 43 patients using coronary angioscopy (CAS) approximately one year after implantation from a cohort of 219 lesions in 158 patients. We set 239 second-generation durable-polymer DES (DP-DES) implanted in 211 lesions from 180 patients from a cohort of 2652 lesions in 1914 patients as the control. Angioscopic images were analyzed to determine (1) the dominant degree of neointimal coverage (NIC) over the stent; (2) the heterogeneity of NIC; (3) yellow color grade of the stented segment; and (4) the presence of intra-stent thrombus. The primary outcome was the incidence of thrombus and secondary outcomes were the other CAS findings, and the 1-year clinical outcomes which included target lesion revascularization (TLR) and major adverse cardiac events (MACE). To minimize inter-group differences in baseline characteristics, propensity score matching was performed for clinical outcomes. RESULTS: Incidence of thrombus adhesion was similar in DCS and DP-DES groups (28.4% versus 22.6%, p=0.31). However, the dominant NIC grade was significantly higher in DCS (p<0.001), while NIC was more heterogeneous in DCS than in DP-DES (p=0.001). Maximum yellow color grade was similar (p=0.22). After propensity score matching, 202 lesion pairs from 146 patient pairs were retained for analysis. The cumulative incidence of TLR (4.6% versus 3.8%, p=0.38) and MACE (11.6% versus 11.7%, p=0.84) was similar for DCS and DP-DES. CONCLUSIONS: DCS showed thrombus adhesion and clinical outcomes at 1 year similar to DP-DES. DCS can thus be used with similar safety and efficacy as DP-DES.

Angioscopic Assessments at 3 Months After Fluoropolymer-Based Paclitaxel-Eluting Stent Implantation for Femoropopliteal Endovascular Intervention.

BACKGROUND: The detailed mechanism of early-phase arterial healing after novel fluoropolymer-based paclitaxel-eluting stent (PES) implantation in the femoropopliteal (FP) lesions has not been elucidated.Methods and Results:We evaluated the intravascular status of 20 PES implanted in 11 FP lesions of 9 patients using angioscopy at approximately 3 months after implantation. Angioscopic images were analyzed to determine (1) the dominant degree of neointimal coverage (NIC) over the stent; (2) the extent of uncovered struts; and (3) the presence of intrastent thrombus. NIC was classified into 4 grades: grade 0, stent struts fully visible; grade 1, stent struts bulging into the lumen although covered; grade 2, stent struts embedded in neointima, but translucently visible; grade 3, stent struts fully embedded and invisible. The extent of uncovered struts was scored as follows: score 0, no uncovered struts of the entire stent; score 1, uncovered struts area approximately <30% of the stent; and score 2, uncovered struts area approximately ≥30% of the stent. In total, 90% of stents demonstrated grade 1 dominant NIC and 10% showed grade 2 dominant NIC; 85% of stents showed an uncovered stent score of 0, and the remainder had a score of 1. Thrombus was observed in all stents. CONCLUSIONS: Widely uncovered stent struts were not observed by angioscopy at 3 months after PES implantation in these FP lesions, even with the detection of thrombus adhesion.

Additional Low-Voltage-Area Ablation in Patients With Paroxysmal Atrial Fibrillation: Results of the Randomized Controlled VOLCANO Trial.

Background The efficacy of low-voltage-area (LVA) ablation has not been well determined. This study aimed to investigate the efficacy of LVA ablation in addition to pulmonary vein isolation on rhythm outcomes in patients with paroxysmal atrial fibrillation (AF). Methods and Results VOLCANO (Catheter Ablation Targeting Low-Voltage Areas After Pulmonary Vein Isolation in Paroxysmal Atrial Fibrillation Patients) trial included paroxysmal AF patients undergoing initial AF ablation. Of 398 patients in whom a left atrial voltage map was obtained after pulmonary vein isolation, 336 (85%) had no LVA (group A). The remaining 62 (15%) patients with LVAs were randomly allocated to undergo LVA ablation (group B, n=30) or not (group C, n=32) in a 1:1 fashion. Primary end point was 1-year AF-recurrence-free survival rate. No adverse events related to LVA ablation occurred. Procedural (124±40 versus 95±33 minutes, P=0.003) and fluoroscopic times (29±11 versus 24±8 minutes, P=0.034) were longer in group B than group C. Patients with LVAs demonstrated lower AF-recurrence-free survival rates (88%) than those without LVA (B, 57%, P<0.0001; C, 53%, P<0.0001). However, LVA ablation in addition to pulmonary vein isolation did not impact AF-recurrence-free survival rate (group B versus C, P=0.67). Conclusions The presence of LVA was a strong predictor of AF recurrence after pulmonary vein isolation in patients with paroxysmal AF. However, LVA ablation had no beneficial impact on 1-year rhythm outcomes. Registration URL: https://www.umin.ac.jp/ctr; Unique identifier: UMIN000023403.

A Global Vascular Guidelines-Based Bypass-Preferred Population and Their Surgical Risk Among CLTI Patients Treated With Endovascular Therapy in a Real-World Practice.

PURPOSE: To determine in a chronic limb-threatening ischemia (CLTI) population who underwent endovascular therapy (EVT) how many patients would have been categorized as preferred for bypass surgery according to the Global Vascular Guidelines (GVG) and ascertain their surgical risk. MATERIALS AND METHODS: The current study analyzed 1043 CLTI patients who presented WIfI (wound, ischemia, and foot infection) stage ≥2 and underwent EVT between April 2010 and December 2017. Of these, 176 were excluded for lack of angiographic or other data, leaving 867 CLTI patients (mean age 74±10 years; 523 men) for stratification according to the GVG into bypass-preferred, indeterminate, or EVT-preferred groups. The GVG recommend bypass as the first-line treatment when the wound is severe (WIfI stage ≥3) and lesions are complex (GLASS stage III). Surgical risk was estimated using the modified PREVENT III risk score. To further stratify the bypass-preferred population according to mortality risk, a survival decision tree was constructed using recursive partitioning. RESULTS: The bypass-preferred group accounted for 55% [95% confidence interval (CI) 51% to 58%] of the overall population. The decision tree analysis extracted a low-mortality risk subgroup with a survival rate of 99% (95% CI 98% to 100%) at 1 month and 80% (95% CI 73% to 87%) at 2 years. According to the PREVENT III score, 34% (95% CI 27% to 42%) of the low mortality risk subgroup were classified as high surgical risk. CONCLUSION: A high proportion of patients undergoing EVT were considered bypass preferred based on the GVG, and the survival of these patients was not significantly different whether they were high or low surgical risk.

A saline contrast-enhanced echocardiography-guided approach to cryoballoon ablation.

BACKGROUND: Pulmonary vein isolation (PVI) with a cryoballoon usually uses iodinated contrast medium for confirmation of venous occlusion. We hypothesized that an alternative to angiography with iodinated contrast, saline bolus-enhanced echocardiography with the microbubbles formed in situ, could be used to assess venous occlusion. We sought to assess the efficacy and safety of the contrast-enhanced intracardiac echocardiographic (ICE) approach. METHODS: Thirty-four consecutive patients without iodine sensitivity or renal insufficiency were studied to assess the accuracy of ICE-guided PV occlusion underwent both angiographic guidance and ICE guidance (validation group). Twenty consecutive patients with paroxysmal atrial fibrillation (AF) and contraindications to iodinated contrast medium (ICE-guided group) underwent PV occlusion and ablation with ICE guidance alone. Procedural results and clinical outcomes were compared with those of 245 control patients undergoing PVI by the conventional angiographic method (control group). RESULTS: In the validation group, ICE-guided PV occlusion was as effective as angiography-guided PV occlusion. In the ICE-guided group, two patients required touch-up ablation using a radiofrequency ablation catheter with fluoroscopic guidance. Procedure time, radiation exposure, and requirements for touch-up ablation were similar between the ICE-guided group and the control group. In patients requiring only PVI, the ICE-guided approach involved significantly less radiation exposure than the conventional approach. There was no significant difference in atrial fibrillation (AF)-free survival rate between the two groups during a follow-up period of 14 ± 6 months. CONCLUSIONS: An echo-guided approach using saline infusion was effective in terms of avoidance of iodinated contrast use and radiation exposure.

Efficacy and safety of the cryoballoon-based atrial fibrillation ablation in patients aged ≥80 years.

INTRODUCTION: The prevalence of atrial fibrillation (AF) increases with age. Although the efficacy of cryoballoon ablation (CB-A) in patients with AF has been demonstrated, data on the efficacy of this CB-A in elderly patients are limited. The aim of this study was to evaluate the 1-year efficacy and safety of CB-A in patients aged ≥80 years compared with those less than 80 years. METHODS: A total of 49 consecutive patients ≥80 years with paroxysmal AF (PAF) who underwent CB-A were compared with 241 patients aged <80 years. AF-free survival rate at 1 year and procedural data were compared between the groups. RESULTS: Median (25th, 75th quartile) age was 83 (82, 85) years in the older group and 68 (61, 73) years in the younger group. At 1-year follow-up, the success rate did not significantly differ between the groups. In Cox regression analysis, age ≥80 years was not significantly related to AF recurrence. Low-voltage areas were more frequently observed in the elderly group than the control group (39% vs 17%; P = .01). Fluoroscopy time and procedure time did not differ significantly. There was no significant difference in the occurrence rate of transient phrenic nerve palsy. No severe complications occurred in either group, including procedure-related deaths, atrioesophageal fistula, cardiac tamponade, and cerebrovascular embolic events. CONCLUSION: The results of our study showed that CB-A for PAF is a feasible and safe procedure even in elderly patients, with similar success and complication rates when compared with a younger population.

Comparison of ablation outcomes of the second ablation procedure for recurrent atrial fibrillation using an ultra-high-resolution mapping system and conventional mappings system.

BACKGROUND: The utility of an ultra-high-resolution electroanatomical mapping system (UHR-EAM, Rhythmia) for repeat atrial fibrillation (AF) ablation has not been evaluated. HYPOTHESIS: A second AF ablation procedure performed using UHR-EAM may demonstrate different outcomes compared with that using a conventional electroanatomical mapping system (C-EAM, CARTO3). METHOD: This observational study enrolled consecutive patients who underwent a second AF ablation procedure using UHR-EAM (n = 103) and C-EAM (n = 153). The second ablation procedure included re-isolation of reconnected pulmonary veins (PVs) and elimination of clinical or induced non-PV AF triggers and atrial tachycardia (AT). Other empirical ablations were additionally conducted at the discretion of the operators. RESULTS: Re-isolation of PVs was achieved in 196 patients who had ≥1 left atrial-PV reconnection. The elimination rate of AT was higher in the UHR-EAM group than the C-EAM group (87% vs 65%, P = .040), while that of non-PV AF triggers was similar (63% vs 63%, P = 1.00). The UHR-EAM demonstrated shorter radiofrequency application time (21.8 ± 16.8 vs 28.0 ± 21.3 minutes, P = .017), but longer fluoroscopic time (26.2 ± 12.6 vs 21.4 ± 9.3 minutes, P = .0001). No severe complication developed. The total 1-year AF/AT-free survival rates were similar between the two groups (off AADs, 59.2% vs 56.2%, P = .62; on AADs, 65.0% vs 69.3%, P = .49). CONCLUSION: The efficacy and safety outcomes of repeat AF ablation using UHR-EAM was comparable to those using C-EAM.

Impact of Renal Dysfunction on Left Atrial Low-Voltage Areas in Patients With Atrial Fibrillation.

BACKGROUND: The presence of residual left atrial low-voltage areas (LVA) has been shown to be strongly associated with atrial fibrillation (AF) recurrence after pulmonary vein isolation. A preliminary study showed that concomitant chronic kidney disease (CKD) increased the rate of AF recurrence. The association between CKD and LVA, however, has not been elucidated. In the present study, we investigated the association between CKD severity and LVA prevalence. Methods and Results: In total, 183 consecutive AF patients who underwent initial ablation for AF were enrolled in this retrospective observational study. Serum cystatin C before ablation was measured, and the estimated glomerular filtration rate (eGFR) was calculated. LVA were defined as sites of left atrial electrogram amplitude <0.5 mV. Of 183 patients, 76 (42%) had LVA. Patients with LVA had lower eGFR calculated using cystatin C (74±22 vs. 86±24 mL/min/1.73 m2, P=0.001). The optimal cut-off of the calculated eGFR was 71.5 mL/min/1.73 m2, corresponding to a 79.4% sensitivity, 50% specificity, and 67.2% predictive accuracy. LVA occurred more frequently in patients with more severe categories of CKD. On multivariate analysis, eGFR <71.5 mL/min/1.73 m2was an independent predictor of LVA (odds ratio, 3.3; 95% CI: 1.4-7.8; P=0.006). CONCLUSIONS: CKD severity was correlated with left atrial LVA prevalence in patients with AF undergoing catheter ablation.

Early- and middle-phase arterial repair following bioresorbable- and durable-polymer drug-eluting stent implantation: An angioscopic study.

BACKGROUND: Bioresorbable-polymer drug-eluting stent (BP-DES) demonstrates comparable clinical outcomes compared to durable-polymer drug-eluting stent (DP-DES). However, early- and middle-phase arterial repair following deployment of BP-DES and DP-DES has not been elucidated to date. METHODS: We extracted coronary angioscopy (CAS) findings covering early phase (4 ±â€¯1 months) or middle phase (10 ±â€¯2 months) between January 2010 and February 2018 from the database of Kansai Rosai Hospital. Neointimal coverage (NIC), yellow color intensity of the stented segment and incidence of thrombus adhesion were compared between BP-DES (Synergy or Ultimaster) and DP-DES (Promus or Resolute or Xience) in early (39 BP-DES of 33 lesions from 24 patients and 83 DP-DES of 74 lesions from 56 patients) and middle (198 BP-DES of 175 lesions from 135 patients and 204 DP-DES of 184 lesions from 149 patients) phases. RESULTS: In early phase, while NIC was similar in both groups (P = 0.84), the incidence of thrombus adhesion was significantly higher in BP-DES than in DP-DES (67% versus 34%, P = 0.001) even though maximum yellow color was less intense in BP-DES (P = 0.004). In middle phase, while NIC was better in BP-DES (P < 0.001), thrombus adhesion (23% versus 22%, P = 0.81) and maximum yellow color (P = 0.72) were similar in both groups. CONCLUSIONS: Although NIC was similar in the early phase, the incidence of thrombus adhesion was significantly higher in BP-DES than in DP-DES. The incidence of thrombus adhesion reached similar values and NIC improved in BP-DES over that in DP-DES in the middle phase.

Comparison of Clinical Outcomes between Endovascular Therapy with Self-Expandable Nitinol Stent and Femoral-Popliteal Bypass for Trans-Atlantic Inter-Society Consensus II C and D Femoropopliteal Lesions.

BACKGROUND: Femoral-popliteal (F-P) bypass is the standard treatment for lower extremity peripheral artery disease with severe femoropopliteal (FP) artery lesions. However, in clinical settings, these patients are treated with endovascular therapy (EVT) because of frailty and difficulties with general anesthesia. We compared the clinical outcomes of F-P bypass and EVT for severe FP artery lesions and investigated the types of patients for whom EVT would be as appropriate as F-P bypass. METHODS: This multicenter, retrospective study included 452 Trans-Atlantic Inter-Society Consensus (TASC) II C and D FP artery lesions in 352 patients. A total of 350 lesions in 260 patients (74 ± 9 years, 66% male, 60% claudication) were treated with EVT with nitinol self-expandable stents, and 102 lesions in 92 patients (71 ± 9 years, 75% male, 40% claudication) were treated with F-P bypass. The primary outcome measure was primary patency, and the influence of baseline characteristics on its association with the treatment strategy (EVT versus F-P bypass) was assessed using a Cox proportional hazards regression model. RESULTS: Kaplan-Meier analysis indicated that the 3-year primary patency rate was significantly lower for EVT than F-P bypass (60% vs. 74%, P < 0.01). The body mass index (BMI) and C-reactive protein (CRP) levels significantly interacted with the treatment strategy for restenosis (P < 0.05). The adjusted hazard ratios of EVT versus F-P bypass for restenosis were 0.77 (P = 0.46) in cases with a low BMI (≤18 kg/m2) or an elevated CRP level (≥1 mg/dL) and 3.35 (P < 0.01) in other cases. The 3-year primary patency rate was not significantly different between the EVT and F-P bypass groups in patients with BMI ≤ 18 kg/m2 or CRP ≥ 1 mg/dL (57% vs. 45%, P = 0.84). CONCLUSIONS: In TASC II C and D lesions, EVT appears to yield patency comparable to that of F-P bypass in patients with a low BMI or an elevated CRP level, but lower patency in other patients.

Pressure monitoring predicts pulmonary vein occlusion in cryoballoon ablation.

PURPOSE: Pulmonary venography is routinely used to confirm pulmonary vein (PV) occlusion during cryoballoon ablation. However, this technique is significantly limited by the risks associated with contrast media, such as renal injury and contrast allergy. We hypothesized that PV occlusion can be predicted by elevation of the balloon catheter tip pressure, avoiding the need for contrast media. METHODS: Forty-eight consecutive patients with paroxysmal atrial fibrillation who underwent PV isolation with the cryoballoon technique were enrolled. The balloon catheter tip pressure was measured in each PV before and after balloon inflation. RESULTS: We analyzed 200 applications of cryoballoon ablation in 185 PVs (excluding 3 common PVs and 1 extremely small right inferior PV) of 48 patients (age, 70 ± 11 years; male, n = 28; mean left atrial diameter, 38 ± 6 mm). Compared with patients with unsuccessful occlusion, patients with successful occlusion demonstrated a larger change in pressure after balloon inflation (6 ± 8 vs. 2 ± 4 mmHg, P < 0.001), a lower minimum temperature (- 49 ± 6 vs. - 40 ± 8 °C, P < 0.001), and a higher PV isolation rate (97 vs. 64%, P < 0.001). The best cutoff value of a change in pressure for predicting PV occlusion was 4.5 mmHg, with a sensitivity of 67%, specificity of 83%, and predictive accuracy of 72%. CONCLUSION: Pressure monitoring is helpful to confirm PV occlusion during cryoballoon ablation.

Regression of luminal stenosis at the site of silent plaque disruption in the era of optimal medical therapy. Low high-density lipoprotein cholesterol level isa potential risk of stenosis progression.

BACKGROUND: Plaque disruption and its healing is thought to be the major mechanism of atherosclerosis, but the contribution of silent plaque disruption to luminal stenosis progression has not been fully clarified. The aim of this study was therefore to examine the change in luminal stenosis at the site of silent plaque disruption. METHODS AND RESULTS: Consecutive patients (n=36) who received coronary angiography and angioscopy that identified silent plaque disruption (baseline) and had repeated coronary angiography later (follow-up) were included for analysis. Silent plaque disruption was defined as plaque with thrombus detected in non-culprit segments. Diameter stenosis of the site was angiographically measured at baseline and at follow-up, and their difference was defined as stenosis change. Statin was used in 89% of study patients, and serum low-density lipoprotein cholesterol level was 91 ± 21 mg/dl. The diameter stenosis decreased significantly from baseline to follow-up at 12 ± 4 months (32 ± 14% vs. 27 ± 14%, P<0.001), and the stenosis change was -5.6 ± 7.9%. High-density lipoprotein cholesterol (HDL-C) was significantly associated with stenosis change (r=-0.51, P=0.001) and was the only factor significantly associated with stenosis change. CONCLUSIONS: In the era of optimal medical therapy with statin, the site of silent plaque disruption showed significant regression of luminal stenosis. Nevertheless, serum HDL-C was inversely associated with stenosis change, and its low level remained as a potential risk of luminal stenosis progression at the site of silent plaque disruption.

Ruptured plaque and large plaque burden are risks of distal embolisation during percutaneous coronary intervention: evaluation by angioscopy and virtual histology intravascular ultrasound imaging.

AIMS: Slow flow and no flow phenomena have been associated with distal embolisation, especially of plaque debris, and with unfavourable clinical outcomes. However, patients at high risk of distal embolisation for whom distal protection might be beneficial have not been adequately identified. We examined the frequency of distal embolisation and its predicting factors, including both ACS and non-ACS patients. METHODS AND RESULTS: Consecutive patients (n=98) with or without ACS who had received PCI with a filter-type distal protection device and successful angioscopic and VH-IVUS examination were prospectively enrolled. The presence of yellow plaque and plaque rupture was evaluated by angioscopy. Tissue classification and plaque burden was evaluated by VH-IVUS. Distal embolisation was evaluated by pathological examination of material collected in the filter. Distal embolisation of plaque debris was more frequently detected in patients with ACS (48% vs. 25%, p=0.02), in those with ruptured plaque (86% vs. 13%, p<0.001), in those with large (>75%) plaque burden (50% vs. 23%, p=0.006), and in those with grade 2/3 yellow plaque (52% vs. 7%, p<0.001), as compared to those without it. CONCLUSIONS: The presence of ruptured yellow plaque and of large plaque burden, rather than the setting of ACS, was highly predictive of distal embolisation of plaque debris.

The level of blood thrombogenicity was not elevated in stable patients with disrupted coronary plaque.

BACKGROUND: Although extremely high blood thrombogenicity has been reported in patients with acute myocardial infarction, it has not been clarified if the increased blood thrombogenicity is a cause of acute myocardial infarction or a mere result induced by thrombus formation at the disrupted plaque. Therefore, we examined if blood thrombogenicity is extremely increased as in acute myocardial infarction patients when disrupted plaque is present in patients with stable coronary artery disease. METHODS AND RESULTS: Consecutive patients (n=38) with stable coronary artery disease who received angioscopic examination were included. Patients were divided into two groups according to presence or absence of disrupted plaque that accompanied thrombus. Blood thrombogenicity was evaluated by blood vulnerability index and compared between the patients with and without disrupted plaque. Among 38 study patients, 16 had disrupted plaque and 22 did not. Blood vulnerability index was not different between the patients with and without disrupted plaque (2395 ± 612 vs. 3013 ± 1476, p=0.12). Multivariate analysis revealed no significant association between blood vulnerability index and the presence of disrupted plaque. CONCLUSION: The presence of disrupted plaque, in comparison with its absence, was not associated with higher blood thrombogenicity evaluated by blood vulnerability index.