Success rate and influencing factors of a balloon-push technique: A new technique to remove side branch-jailed struts under three-dimensional optical coherence tomography guidance.

BACKGROUND: Kissing balloon inflation with distal guide wire recross can cause severe stent deformation depending on the stent link location with respect to the carina. The balloon-push technique, by which an inflated balloon is forced into the SB from the proximal main vessel (MV), is a feasible way to remove jailed struts without causing severe stent deformation. AIMS: We investigated the procedural success rate, patterns of jailed strut removal at side branch (SB) orifices, factors related to failure of jailed strut removal, and follow-up angiogram results of the balloon-push technique. METHODS: Between September 2015 and December 2020, 51 bifurcation stenting cases in which the balloon-push technique was used were enrolled. Based on three-dimensional optical coherence tomography images, strut removal with 1 stent crown length was defined as successful. Strut removal patterns were classified into two types: parallel-slide type (stent struts shifted distally into the MV lumen without inversion) and under-carina type (stent struts shifted distally under the carina with strut inversion or strut slide). RESULTS: Procedural success was attained in 39 cases (success rate: 76.5%). Parallel-slide type and under-carina type occurred in 43% and 33% of cases, respectively. Factors related to failure were trifurcation lesions and a smaller pushed balloon-SB artery ratio compared with those in success cases (0.95 ± 0.18 vs. 1.10 ± 0.22, p = 0.032). Follow-up angiography was performed in 37 cases, and 2 cases had binary in-stent restenosis. CONCLUSIONS: Removal of jailed struts with the balloon-push technique was feasible, without severe stent deformation, in bifurcation stentings.

Peri-Balloon Leak Flow Velocity Assessed by Intra-Cardiac Echography Predicts Pulmonary Vein Electrical Gap　- Intra-Cardiac Echography-Guided Contrast-Free Cryoballoon Ablation.

BACKGROUND: The use of iodine contrast agents is one possible limitation in cryoballoon ablation (CBA) for atrial fibrillation (AF). This study investigated intracardiac echography (ICE)-guided contrast-free CBA.Methods and Results:The study was divided into 2 phases. First, 25 paroxysmal AF patients (Group 1) underwent CBA, and peri-balloon leak flow velocity (PLFV) was assessed using ICE and electrical pulmonary vein (PV) lesion gaps were assessed by high-density electroanatomical mapping. Then, 24 patients (Group 2) underwent ICE-guided CBA and were compared with 25 patients who underwent conventional CBA (historical controls). In Group 1, there was a significant correlation between PLFV and electrical PV gap diameter (r=-0.715, P<0.001). PLFV was higher without than with an electrical gap (mean [±SD] 127.0±28.6 vs. 66.6±21.0 cm/s; P<0.001) and the cut-off value of PLFV to predict electrical isolation was 105.7 cm/s (sensitivity 0.700, specificity 0.929). In Group 2, ICE-guided CBA was successfully performed with acute electrical isolation of all PVs and without the need for "rescue" contrast injection. Atrial tachyarrhythmia recurrence at 6 months did not differ between ICE-guided and conventional CBA (3/24 [12.5%] vs. 5/25 [20.0%], respectively; P=0.973, log-rank test). CONCLUSIONS: PLFV predicted the presence of an electrical PV gap after CBA. ICE-guided CBA was feasible and safe, and could potentially be performed completely contrast-free without a decrease in ablation efficacy.

Predictor analysis of 1-year restenosis after percutaneous transluminal angioplasty for femoropopliteal stenotic lesions using intravascular ultrasound.

This retrospective, single-center study evaluated the patency rate and predictors of restenosis after percutaneous transluminal angioplasty (PTA) for femoropopliteal stenotic lesions using intravascular ultrasound. We assessed 78 de novo femoropopliteal stenotic lesions (64 patients; mean age, 73.6 ± 9.4 years; average lesion length, 59.8 mm) that underwent PTA under intravascular ultrasound guidance. The primary endpoint was 1-year primary patency. The 1-year primary patency rate was 63%. The frequency of insulin use was significantly greater (44% vs. 12%, p = 0.005), and lesions were significantly longer (77.8 mm vs. 49.2 mm, p = 0.047) in the restenosis group than in the non-restenosis group. The pre-intervention reference lumen area and minimum lumen area (MLA) were significantly smaller in the restenosis group (reference lumen area: 19.7 ± 6.7 mm2 vs. 23.7 ± 7.4 mm2, p = 0.017; MLA 3.9 ± 2.8 mm2 vs. 5.7 ± 3.9 mm2, p = 0.026; respectively). The MLA was significantly smaller and the maximum angle of dissection was significantly larger in the restenosis group (MLA 9.3 mm2 vs. 12.3 mm2, p = 0.013; maximum angle of dissection: 104.1° vs. 69.6°, p = 0.003; respectively) among post-intervention parameters. Multivariate analysis revealed that the independent predictors of 1-year restenosis were the large post-intervention maximum angle of dissection and insulin use. Per receiver operating curve analysis, the best cut-off value of the post-intervention maximum angle of dissection that predicted 1-year restenosis was 70.2° (sensitivity 72.4%, specificity 63.3%, area under the curve 0.70, p = 0.004). In conclusion, the 1-year primary patency rate after PTA for relatively short stenotic femoropopliteal lesions was 63%. The large post-intervention maximum angle of dissection, measured using intravascular ultrasound, and insulin use were independent predictors of restenosis after PTA.

Outcomes of Dissection Angles as Predictor of Restenosis after Drug-Coated Balloon Treatment.

AIM: The predictors of restenosis after endovascular therapy (EVT) with paclitaxel drug-coated balloons (DCBs) have not been clearly established. The present study aimed to investigate the association of post-procedural dissection, as evaluated using intravascular ultrasound (IVUS), with the risk of restenosis following femoropopliteal EVT with paclitaxel DCBs. METHODS: In the present single-center retrospective study, 60 de novo femoropopliteal lesions (44 patients) that underwent EVT with DCBs, without bail-out stenting, were enrolled. The primary outcome was 1-year primary patency. Risk factors for restenosis were evaluated using a Cox proportional hazards regression model and random survival forest analysis. RESULTS: The 1-year primary patency rate was 57.2% [95% confidence interval, 45%-72%]. IVUS-evaluated post-procedural dissection was significantly associated with the risk of restenosis (P=0.002), with the best cutoff point of 64º [range, 39º-83º]. The random survival forest analysis showed that the variable importance measure of IVUS-evaluated dissection was significantly lower than that of the reference vessel diameter (P＜0.001), not different from that of the lesion length (P=0.41), and significantly higher than that of any other clinical feature (all P＜0.05). CONCLUSION: IVUS-evaluated post-procedural dissection was associated with 1-year restenosis following femoropopliteal EVT with DCB.

Techniques for reducing air bubble intrusion into the left atrium during radiofrequency catheter and cryoballoon ablation procedures: An ex vivo study with a high-resolution camera.

BACKGROUND: Air embolisms are serious complications during catheter ablation procedures. OBJECTIVES: The aims of the present study were to determine when air bubbles enter the left atrium (LA) during catheter ablation procedures and to identify techniques that reduce air bubble intrusion. METHODS: An ex vivo study was performed to monitor air bubbles using a silicone heart model and a high-resolution camera. In total, 280 radiofrequency catheter and cryoballoon ablation processes were tested. RESULTS: Small and large air bubbles were often observed during catheter ablation processes. Many small air bubbles arose during sheath flushing at fast speeds (15 mL/2 s) (median bubble number [quartiles]: 35 [20-53] for SL0, 35 [23-44] for Agilis, and 98 [91-100] for FlexCath) and during initial cryoballoon inflation/freezing/deflation (34 [22-47]). Large (≥1.5 mm) air bubbles were observed during Lasso catheter insertion (1 [0-1]), cryoballoon insertion (2 [1-2]), and initial inflation/freezing/deflation (1 [1-3]). Massive air bubbles were observed during Optima catheter insertion into the sheath using an inserter (10 [2-15]). Sheath flushing at slow speeds (15 mL/5 s) significantly reduced the number of air bubbles. Before cryoballoon insertion, temporary balloon inflation and air bubble removal from the inflated surface were most effective in reducing air bubble intrusions. Optima catheter insertion without an inserter significantly reduced large air bubble intrusion. CONCLUSION: Air bubbles entered the LA at specific times. Techniques such as sheath flushing at slow speeds, temporary cryoballoon inflation before insertion, inserting the Optima catheter without an inserter, and avoidance of negative pressure in the LA could reduce air bubble intrusion.

Feasibility and usefulness of three-dimensional optical coherence tomography guidance for optimal side branch treatment in coronary bifurcation stenting.

BACKGROUND: For the treatment of coronary bifurcation lesions, optimal guidewire (GW) recrossing after main vessel stenting is important for good stent apposition at the side branch (SB) orifice in kissing balloon inflation (KBI). METHODS: We analyzed 150 bifurcation lesions treated with single stenting following KBI in the three-dimensional optical coherence tomography (3D-OCT) bifurcation registry study (2015-16) and a single center experience (2012-16). OCT examination was performed after GW recrossing to the SB and after KBI. Patients were divided into two-dimensional (2D, n=78) and 3D groups (n=72) according to 2D- or 3D-OCT guidance. GW recrossing position, jailing configuration of the stent over the SB (divided into Link-connecting type: stent link connecting to the carina and Link-free type: no stent link at the carina) and stent apposition were compared between the groups. RESULTS: Distal GW recrossing was achieved in 75.6% and 91.7% in the 2D and 3D groups, respectively (P=0.004). Compared with the 2D group, the incidence of incomplete stent apposition (ISA) toward the SB in the 3D group tended to be lower in the whole cohort (14.5±13.6% vs 10.0±9.0%, P=0.077), and was significantly lower in left main trunk bifurcations (18.7±12.8% vs 10.3±8.9%, P=0.014). Independent contributors to ISA were the Link-connecting type (ß 0.089, P<0.001), distal GW recrossing (ß -0.078, P=0.001), and age (ß -0.0020, P=0.012). CONCLUSION: Optimal GW recrossing under 3D-OCT guidance is feasible and improves stent apposition, which may lead to a better clinical outcome in the treatment of bifurcation lesions.

Potent effect of prasugrel on acute phase resolution of intra-stent athero-thrombotic burden after percutaneous intervention to acute coronary syndrome.

BACKGROUND: Recent studies suggested protruding thrombus and atheroma after stent placement could be a substrate for subsequent adverse ischemic events. Although protruded atherothrombotic burden can be assessed as intra-stent tissue (IST) by optical coherence tomography (OCT), the effects of potent antiplatelet therapy on the acute phase resolution of IST in patients with acute coronary syndrome (ACS) was unknown. METHODS: Ninety-six consecutive ACS patients with multi-vessel disease were enrolled in this prospective registry. In combination with aspirin, either clopidogrel or prasugrel was selected according to the date of enrolment. OCT examination was done immediately after percutaneous coronary intervention (post-PCI) and 10 days after index PCI (follow-up acute phase) to calculate averaged IST score as semi-quantitative measures of IST. High residual platelet reactivity (HRPR) was defined as platelet reactivity units (PRU)≥240 by VerifyNow P2Y12 assay (Accumetrics Inc., San Diego, CA, USA). RESULTS: Thirty two patients (38 stents) were enrolled in the prasugrel group and sixty four patients (72 stents) in the clopidogrel group. Averaged IST scores post-PCI were similar between the two groups (0.68±0.41 vs. 0.68±0.40, p=0.99), which decreased in all of the prasugrel group and in 87.5% of the clopidogrel group (p=0.02). Consequently, changes in averaged IST score (delta averaged IST score) were significantly greater in the prasugrel group compared to those in the clopidogrel group (-0.411±0.288 vs. -0.299±0.270, p=0.045). The frequency of HRPR was significantly lower in the prasugrel group (10.0% vs 32.4%, p=0.028). CONCLUSIONS: Prasugrel plus aspirin achieved greater acute phase reduction of IST than clopidogrel plus aspirin, which might underlie the clinical benefit of potent antiplatelet therapy in ACS. (UMIN000018751).

Data on two- and three-dimensional optical coherence tomography guidance for the treatment for the bifurcation lesion.

This article comprised the data related to the research article entitled "Feasibility and usefulness of three-dimensional optical coherence tomography guidance for optimal side branch treatment in coronary bifurcation stenting" (Nagoshi et al., In press) [1]. In this article we reports details about two patterns of guide wire (GW) recrossing position after crossover stenting in bifurcation lesion classified with three-dimensional optical coherence tomography (3D-OCT) (Okamura et al., 2014) [2] and follow-up data about the treatment with percutaneous coronary intervention(PCI) for bifurcation lesion in terms of the two- (2D) or 3D-OCT guidance. Subgroup analysis about differences in the parameters between the proximal and the distal GW recrossing patterns are analyzed here.

The importance of catheter stability evaluated by Visitag(TM) during pulmonary vein isolation.

BACKGROUND: The recurrence rates of atrial fibrillation (Af) after ablation are still high, and repeat procedures are required in these patients. The main reason for Af recurrence is the recovery of the conduction between the pulmonary veins and left atrium. The importance of catheter stability during the pulmonary vein isolation (PVI) is not well studied. PURPOSE: The purpose of this study was to evaluate the contact force (CF), stable ablation time, and power during conduction blocking lesion formation for PVI. METHODS: Thirty-two consecutive drug-refractory Af patients who underwent an initial PVI using CARTO 3 and Visitag were included. The CF, ablation time, force time integral (FTI), and ablation power were recorded by Visitag. Residual conduction gap points requiring touch-up ablation after an encircling linear ablation (R point), spontaneous reconnection points (S point), and dormant conduction points (D point) were considered as non-conduction blocking lesion points. Each ablation parameter for the non-conduction blocking lesion points was compared with the other lesion points. RESULTS: Twenty-one points in 16 patients were considered non-conduction blocking lesions. Ten were R, eight were S, and three were D points. The CF, ablation time, FTI, and power at the non-conduction blocking lesion points and other points were 12.0 g (7.0-21.5) and 12.0 g (9.0-16.0) (P = 0.9), 7.7 s (5.6-10.1) and 12.5 s (9.4-16.8) (P < 0.05), 103.0 g*s (62.0-174.5) and 149.0 g*s (104.0-213.0) (P < 0.05), and 30.0 W (22.5-30.0) and 30.0 W (30.0-30.0) (P = 0.06), respectively. CONCLUSIONS: Shorter ablation time recorded in Visitag lead to non-conduction blocking lesion.

Optical coherence tomography study of chronic-phase vessel healing after implantation of bare metal and paclitaxel-eluting self-expanding nitinol stents in the superficial femoral artery.

BACKGROUND: This study aimed to assess chronic-phase suppression of neointimal proliferation and arterial healing following paclitaxel-coated (PTX) and bare metal stent (BMS) implantation in the superficial femoral artery using optical coherence tomography (OCT). METHODS: Twenty-five patients with 68 stents underwent an 8-month OCT follow-up. Besides standard OCT variables, neointimal characterization and frequencies of peri-strut low-intensity area (PLIA), macrophage accumulation, and in-stent thrombi were evaluated. RESULTS: The mean neointimal thickness was significantly less with PTX stents (544.9±202.2 µm vs. 865.0±230.6 µm, p<0.0001). The covered and uncovered strut frequencies were significantly smaller and larger, respectively, in the PTX stent group vs. the BMS group (93.7% vs. 99.4%; p<0.0001, 4.0% vs. 0.4%; p<0.0001, respectively). Heterogeneous neointima was only observed in the PTX stent group (12.5% vs. 0%, p=0.017). The frequencies of PLIA and macrophage accumulation were significantly greater in the PTX stent group (87.2% vs. 67.6%, p=0.001 and 46% vs. 9.1%, p=0.003, respectively). CONCLUSION: After 8 months, reduced neointimal proliferation was observed with PTX stent implantation. On the other hand, delayed arterial healing was observed compared with BMS.

Torsades de Pointes with QT prolongation related to donepezil use.

An 83-year-old female, who had a history of anterior myocardial infarction, was treated for Alzheimer's disease with donepezil. She suffered from repeated diarrhea and vomiting, and experienced syncope. She was admitted to our hospital and was diagnosed with acute colitis and syncope. On admission, her heart rate was 54 beats/min with regular rhythm. Laboratory data showed a low plasma potassium level. Electrocardiogram (ECG) showed poor R progression, ST elevation, negative T in precordial leads, and marked QT prolongation. Transthoracic echocardiogram showed the enlargement of the left atrium and aneurysmal area at the apex. Torsades de Pointes (TdP) with syncope and convulsion were confirmed on ECG monitoring twice after admission. We treated her with potassium chloride and started magnesium sulfate and lidocaine, and then added isoprenaline injection. After these treatments, her heart rate increased and we did not detect TdP again. With the aging population in Japan, prescriptions for donepezil are increasing. We have to be vigilant for syncope in patients taking donepezil, which is possibly related to QT prolongation and TdP.

Usefulness of transesophageal echocardiographic observation during chemotherapy for cardiac metastasis of non-Hodgkin lymphoma complicated with left ventricular diastolic collapse.

A 53-year-old man, who had been treated for penile origin diffuse large B cell type non-Hodgkin lymphoma (NHL), suffered from right femoral pain and dyspnea. Positron emission tomography (PET) revealed abnormal accumulation in his right femur and cardiac segments. Transthoracic echocardiography revealed massive localized pericardial effusion with the collapse of both ventricles and the mass-like echo in the left atrium. We performed emergent pericardiocentesis and diagnosed this case as a recurrence of NHL with cardiac metastasis. With the use of transesophageal echocardiography (TEE), we confirmed the mass-like echo around the inter-atrial septum, which directly invaded to the aortic ring and the right atrial wall. In order to evaluate the effect of chemotherapy, we performed TEE and observed the precise changes of intra-cardiac tumor size. With the use of TEE monitoring, we could select the appropriate chemotherapeutic regimen, and the tumor became smaller and finally diminished. The femoral accumulation detected by PET also disappeared. We experienced a case of cardiac metastasis of NHL complicated with left ventricular diastolic collapse due to the massive localized pericardial effusion. TEE is a useful tool to evaluate precisely the efficacy of chemotherapy for intra-cardiac tumors.

Mitral regurgitation resulting from the consecutive multiple perforations by infective endocarditis mimicking the isolated anterior mitral cleft.

A 60-year-old man, suffering from sustained cough and dyspnea on effort, was diagnosed as congestive heart failure. He did not yield the history of having fever or other inflammatory events. His physical examination disclosed a pan-systolic murmur at the apex. Transthoracic color Doppler echocardiography showed moderate to severe mitral regurgitation originated from the linear tear of the anterior mitral leaflet. The tear reached to the mid-portion of the leaflet just within the postero-medial commissure and the regurgitant flow convergence was not hemispheric, but box-like shaped, suggesting that the linear tear was the isolated mitral cleft. Transesophageal echocardiography showed the almost same findings and we found no other anomalies. Surgical treatment was selected to repair the mitral regurgitation. Under operation, we found three consecutive perforations located linearly in the anterior mitral leaflet. The mitral valve replaced with the prosthetic one. The pathological examination of the resected valve showed mucinous degeneration of the chordae tendineae and fibrinoid change without inflammatory cellular infiltration. These findings were compatible with the healed infective endocarditis. Here we experienced a curious case of mitral regurgitation, caused by consecutive three mitral perforations mimicking the isolated anterior mitral cleft.

Inhibition of endogenous nitric oxide synthase augments contractile response to adenylyl cyclase stimulation without altering mechanical efficiency in patients with idiopathic dilated cardiomyopathy.

BACKGROUND: Increased nitric oxide (NO) in the failing heart attenuates the myocardial contractile response to beta-adrenergic receptor stimulation. However, the physiological effects of NO on the beta-adrenergic post-receptor signaling system are unknown. The objective of the present study was to examine the effects of cardiac NO synthase (NOS) inhibition on left ventricular (LV) hemodynamics and mechanoenergetics in response to adenylyl cyclase stimulation in human heart failure. METHODS AND RESULTS: The study group comprised 13 patients with heart failure because of idiopathic cardiomyopathy (IDC). Emax was examined as an index of LV contractility, LV external work (EW), pressure-volume area (PVA), myocardial oxygen consumption (MVO2), and mechanical efficiency (EW/MVO2) with the use of conductance and coronary sinus thermodilution catheters before and during colforsin daropate infusion, and during concurrent infusion of colforsin daropate with the NOS inhibitor, NG-monomethyl-L-arginine (L-NMMA; 200 micromol). Colforsin daropate increased Emax by 53% and EW by 18%, and reduced PVA by 14%, without altering MVO2 or mechanical efficiency. The combination of colforsin daropate with L-NMMA further increased Emax by 26% and reduced PVA by 9%, without altering MVO2 or mechanical efficiency. CONCLUSIONS: These findings suggest endogenous NO may modulate beta-adrenergic post-receptor pathways and preserve myocardial efficiency in patients with IDC.