Nobuyuki Morioka

The performance of renal duplex ultrasonography for the detection of hemodynamically significant renal artery stenosis

Objectives: The value of renal duplex ultrasonography for the detection of angiographical renal artery stenosis (RAS) has been demonstrated in many clinical studies. None of the published studies, however, have adequately scrutinized the performance of this modality for the detection of hemodynamically significant RAS. The purpose of this study is to investigate the correlation and accuracy between renal duplex parameters and translesional pressure gradient (TLPG). Methods: A total of 60 patients, with 75 stenotic lesions in the renal arteries determined by angiography, underwent duplex ultrasonography before angiography and the measurement of TLPG using a 0.014″ pressure wire in the single setting of angiography were prospectively included. Peak systolic velocity (PSV) in the renal artery and a ratio of PSV in the renal artery to the aorta (RAR) were examined as duplex ultrasonography parameters. Angiographical stenosis was evaluated by percent diameter stenosis (%DS) derived from quantitative angiographic analysis. Results: The correlation with TLPG proved to be stronger in the following order, PSV (r = 0.743, P < 0.001), %DS (r = 0.701, P < 0.001), and RAR (r = 0.572, P < 0.001). The best performing parameter for TLPG of 20 mm Hg was revealed to be PSV, as the areas under the receiver operator characteristics curves using %DS, PSV, and RAR were 0.888, 0.939, and 0.834, respectively. A PSV cutoff value of 219 cm/sec provided the best predictive value with a sensitivity of 89%, a specificity of 89%, and an accuracy of 89%. The positive predictive value was 83% and the negative predictive value was 93%. Conclusions: The measurement of PSV is not only noninvasive but also highly accurate in detecting patients who have hemodynamically significant RAS. The authors emphasize that an enthusiastic application of renal duplex ultrasonography, particularly the measurement of PSV, is warranted.

Sirolimus-Eluting Stent Versus Balloon Angioplasty for Sirolimus-Eluting Stent Restenosis: Insights From the j-Cypher Registry

Background— Optimal treatment strategies for restenosis of sirolimus-eluting stents (SES) have not been adequately addressed yet. Methods and Results— During the 3-year follow-up of 12 824 patients enrolled in the j-Cypher registry, 1456 lesions in 1298 patients underwent target-lesion revascularization (TLR). Excluding 362 lesions undergoing TLR for stent thrombosis or TLR using treatment modalities other than SES or balloon angioplasty (BA), 1094 lesions with SES-associated restenosis in 990 patients treated with either SES (537 lesions) or BA (557 lesions) constituted the study population for the analysis of recurrent TLR and stent thrombosis after the first TLR. Excluding 24 patients with both SES- and BA-treated lesions, 966 patients constituted the analysis set for the mortality outcome. Cumulative incidence of recurrent TLR in the SES-treated restenosis lesions was significantly lower than that in the BA-treated restenosis lesions (23.8% versus 37.7% at 2 years after the first TLR; P<0.0001). Among 33 baseline variables evaluated, only hemodialysis was identified to be the independent risk factor for recurrent TLR by a multivariable logistic regression analysis. After adjusting for confounders, repeated SES implantation was associated with a strong treatment effect in preventing recurrent TLR over BA (odds ratio, 0.44; 95% confidence interval, 0.32 to 0.61; P<0.0001). The 2-year mortality and stent thrombosis rates between the SES- and the BA-treated groups were 10.4% versus 10.8% (P=0.4) and 0.6% versus 0.6%, respectively. Conclusions— Repeated implantation of SES for SES-associated restenosis is more effective in preventing recurrent TLR than treatment with BA, without evidence of safety concerns.

Long-term results of primary stenting for subclavian artery disease

To evaluate initial and long‐term results of endovascular therapy (EVT) for symptomatic subclavian artery (SCA) disease. Background: EVT for SCA disease has a similar success rate as open surgery, but the long‐term patency of EVT alone is uncertain.

Transradial intervention for native fistula failure

The native radiocephalic (Brescia‐Cimino) fistula is usually constructed with an anastomosis of the cephalic vein and radial artery. Catheter interventions for native fistula failure have until now been performed via the transcephalic or transbrachial approach. Transradial intervention for native fistula failure was prospectively evaluated for a selected consecutive 11 patients. Six patients had a single lesion and 5 patients had double lesions. Twelve lesions were stenotic and 4 were occlusive with thrombus. Balloon angioplasty alone was successful in 10 lesions. In thrombosed fistulas, 2 lesions underwent manual catheter‐directed thrombo‐aspiration and 2 further lesions underwent a combination of catheter‐directed thrombo‐aspiration and mechanical thrombectomy. Cutting Balloon angioplasty was performed for 3 resistant venous stenoses and for 1 radial artery stenosis. Technical and clinical success were achieved in all patients. No vessel rupture or perforation was observed in this study, nor was distal embolization in the radial artery or symptomatic pulmonary embolism. No radial artery occlusion or fistula infection was seen during the follow‐up. The primary patency rates were 82% at 3 months and 64% at 6 months. Transradial intervention for native fistula failure is considered safe and feasible in a selected population; yet requires further validation.

Chronic total occlusions in the superficial femoral artery: a novel strategy using a 1.5 mm J-tip hydrophilic guidewire with an over-the-wire balloon catheter under ultrasound guidance.

Chronic total occlusions in the superficial femoral artery (SFA) are the longest and straightest lesions in the whole body. This presents additional technical challenges and the inability to cross the occluded lesion is a common cause of procedural failure in these percutaneous interventions. The objective of this study was to investigate the usefulness of a strategy using a hydrophilic 1.5 mm J‐tip 0.035″ guidewire with an over‐the‐wire balloon catheter under ultrasound guidance for chronic total occlusions in the SFA. This strategy was performed in 32 consecutive patients (36 limbs). Average occlusion length was 17 ± 10 cm (3–40 cm). The crossover approach was performed in 26 cases (72%); in the remaining 10 cases, the antegrade ipsilateral approach was selected. The technical success rate was 92% (32/36). A secondary popliteal artery approach was performed in the three failed limbs and was successful in two limbs, increasing the final technical success rate to 97%. This novel procedure may be considered the preferred strategy for intervening in chronic total occlusions in the SFA.

Impact of changing PSVR thresholds on the patency rates of SFA recanalisation with self-expanding nitinol stents.

AIMS The primary patency of superficial femoral artery (SFA) stents is evaluated by measuring PSVR. However, each trial uses a different definition of PSVR. We investigated the impact of changing PSVR thresholds on the patency rates of SFA recanalisation with self-expanding nitinol stents. METHODS AND RESULTS A single-centre retrospective study was conducted. Between 2003 and 2006, 76 consecutive patients (83 limbs) were treated using nitinol self-expanding stents for SFA disease. Primary patency was defined as categories 1 (PSVR <2.0), 2 (PSVR <2.4) and 3 (PSVR <2.85). The mean follow-up time was 51±27 months. For one, five, and seven years, Kaplan-Meier estimates for primary patency rates were 62.6%, 36.8%, and 27.6%, respectively, in category 1; 75.2%, 46.5%, and 37.1%, respectively, in 2; and 75.2%, 46.1%, and 46.1%, respectively, in 3. The primary patency between categories 1 and 3 (p=0.038) was significantly different. No difference was observed between categories 2 and 3 (p=0.786), and a trend for differences was observed between categories 1 and 2 (p=0.069). CONCLUSIONS PSVR definition may influence the reported long-term patency rate of a SFA stent. We should consider the definition of restenosis in each trial.

A case of an incision-related single-loop intra-atrial reentrant tachycardia showing an eccentric atrial activation sequence and widely separate potentials resembling a double-loop reentry; its mechanism and analysis

Introduction A supraventricular reentrant tachycardia (SVT) appearing after cardiac surgery is known to have a complicated reentrant circuit, such as a figure-8 pattern based on a double-loop reentry using both an incisional line and the cavotricuspid isthmus (CTI). In order to determine the reentrant circuit of the SVT, detailed mapping using a 3-dimensional (3-D) electroanatomical mapping system during the tachycardia is essential. We present an incision-related single-loop reentrant SVT, resembling a double-loop reentry, which was correctly diagnosed by analyzing the special positional relationship between the multipolar electrode catheter and the incision.

A case of typical atrioventricular nodal (AVN) reentrant tachycardia confined to the compact AV node, showing a variety of rare electrophysiological findings, including eccentric AVN echoes

Herein, we report the case of a 49‐year‐old woman with typical atrioventricular nodal (AVN) reentrant tachycardia, confined to the compact atrioventricular node, showing numerous rare electrophysiological findings such as unique AVN reentrant echoes, double ventricular responses, latent retrograde dual AVN pathways, antegrade triple AVN pathways, and longitudinal dissociation within the lower final common pathway.

A Case of Epicardial RV-VT Eliminated by Endocardial Ablation

A 66-year-old female had ECG similar to type 1-Brugada and VT showing LBBB+LAD. EPS and radiofrequency (RF) ablation were performed with NavX system. A 3D-electroanatomic voltage map on an endocardial RV geometry indicated that low amplitude potentials (less than 0.5 mV) existed in infero-basal and apical walls. Activation mapping during a VT induced by programmed RV stimulation was achieved using an irrigated 4-mm-tip ablation catheter, so that the VT was confirmed a focal pattern originating from within the infero-basal low voltage area. This earliest activation site during the VT had a QS pattern on a unipolar intracardiac electrogram of the catheter and preceded about 10 ms from onset of QRS wave. Initial irrigated catheter ablation was performed here on the condition of a 20-watt power or 40C temperature limit and a flow rate of 13 ml/min, only resulting in transient termination of the VT. However, the shift of the earliest site to mid-inferior area, showing a normal amplitude (more than 1.5 mV), was clarified by further activation mapping. Additionally, perfect pace-mapping was obtained from the site. Although the potential on a unipolar electrogram of this site depicted no QS pattern during the VT, ablation could terminate the VT and render its inducibility impossible. These findings may suggest that endocardial RF ablation could eliminate focal VT originating from epicardial RV.

LONG-TERM MORTALITY AFTER ENDOVASCULAR TREATMENT FOR CRITICAL LIMB ISCHEMIA WITH TISSUE LOSS

Results: The mean age was 70±10 (range, 37-94) years. Eighty patients (66%) had diabetic mellitus and 54 (44%) had end-stage renal disease (ESRD) (53: hemodialysis, 1: peritoneal dialysis). During the mean follow-up time of 20±19 (range, 1-104) months, 5 (5%) were sent to bypass surgery and 13 (11%) resulted in major amputation. Also, 32 patients (26%) died, 7 from cardiac and 25 from non-cardiac reasons. Limb salvage was 93% at 2 years and 90% at 5 years, respectively. Cox proportional hazards multivariate analysis identified ESRD (P=0.002) and age (P=0.045) as independent predictors of long-term mortality. Long-term survival rate was 69% at 2 years and 56% at 5 years, respectively, and was significantly (P=0.0045) lower in ESRD patients than in non-ESRD patients (Figure).