Comparison of Subsequent Inframalleolar Bypass Surgery and Repeat Endovascular Therapy for Infrapopliteal Restenosis in Patients With Chronic Limb-Threatening Ischemia Undergoing Primary Endovascular Therapy.

PURPOSE: Although endovascular therapy (EVT) is considered a vital strategy for treating infrapopliteal lesions in chronic limb-threatening ischemia (CLTI), the recurrence rate after EVT exceeds that after bypass surgery (BSX). The optimal approach for managing infrapopliteal lesion recurrence in patients with CLTI and unhealed ulcers remains uncertain. This study aimed to evaluate the clinical outcomes of repeat EVT and subsequent inframalleolar BSX for CLTI with infrapopliteal lesion recurrence. MATERIALS AND METHODS: We conducted a retrospective analysis of 140 patients with CLTI (mean age, 70±10 years; male, 71.4%; diabetes mellitus, 73.6%; dialysis, 74.3%; Rutherford 5, 79.3%; and Rutherford 6, 20.7%) who had an unhealed wound due to the recurrence of infrapopliteal lesions between January 2015 and May 2020. We compared the clinical outcomes of 40 patients who underwent the subsequent inframalleolar BSX with those of 100 patients who underwent repeat EVT. The outcome measures were amputation-free survival (AFS) and wound healing rate. Propensity score matching analysis was conducted to minimize differences in baseline characteristics. RESULTS: Propensity score matching extracted 38 pairs (38 patients in the subsequent BSX group and 83 patients in the repeat EVT group). AFS was not significantly different between the repeat EVT and subsequent BSX groups (81.9% vs 82.6% at 1 year, p=0.97). Neither was cumulative wound healing (42.8% vs 43.3% at 1 year, p=0.55). No baseline characteristics had any significant interaction effect on the association between repeat EVT, subsequent BSX, and failure of AFS. CONCLUSION: This study using propensity score matching revealed that the clinical outcomes following repeat EVT were comparable with those following subsequent inframalleolar BSX, indicating that repeat EVT may be a viable treatment option for CLTI with infrapopliteal lesion recurrence. CLINICAL IMPACT: Although endovascular therapy (EVT) has expanded the treatment options for chronic limb-threatening ischemia (CLTI), the recurrence rate after EVT is higher than that after bypass surgery (BSX). This retrospective study compared the clinical outcomes of repeat EVT with those of subsequent BSX for CLTI with infrapopliteal lesion recurrence. After propensity score matching, amputation-free survival (AFS) was not significantly different between the repeat EVT and subsequent BSX groups (81.9% vs 82.6% at 1 year, p=0.97). Neither was cumulative wound healing (42.8% vs 43.3% at 1 year, p=0.55). There was no difference between the 2 revascularization strategies when treating infrapopliteal restenosis lesions.

Outcomes of revascularization of stenotic inframalleolar lesions in chronic limb-threatening ischemia.

BACKGROUND: For chronic limb-threatening ischemia, revascularization has been reported for occlusions but not for stenosis in the inframalleolar (IM) lesions. We investigated the clinical outcomes of balloon dilation for stenotic IM lesions distal to the treatment target in the infrapopliteal (IP) legion. METHODS: We conducted a retrospective analysis of patients who had chronic limb-threatening ischemia and underwent revascularization of stenotic IM lesions distal to the target IP lesions between January 2015 and August 2022. The outcome measures were amputation-free survival, wound healing rate, and freedom from target IM reintervention. RESULTS: The 87 patients had a mean age of 72.7 ± 10.7 years and comprised 67.8% men, 74.7% with diabetes mellitus, 55.2% on dialysis, 33.3% who had Rutherford six classification. The amputation-free survival (AFS), wound healing, and freedom from target IM reintervention rates at 1 year were 82.9%, 53.3%, and 58.4%, respectively. On Cox proportional multivariate analysis, the predictors were Wound, Ischemia, and foot Infection (WIfI) ≥3 and diffuse stenosis in the target IM vessels for delayed wound healing and Global Limb Anatomic Staging System stage Ⅲ and ≥3 diseased IM vessels before endovascular therapy for target IM reintervention. At the time of reintervention, the lesion morphology had progressed from stenosis to occlusion in 50% of cases. CONCLUSIONS: In patients with chronic limb-threatening ischemia, revascularization of stenosis in IM lesions showed a high reintervention rate and progression of lesion morphology, although AFS and wound-healing rates were acceptable.

Bipolar radiofrequency ablation for re-entrant ventricular tachycardia of right bundle branch block and left bundle branch block morphologies with the common slow conduction zone at the left ventricular summit: a case report.

Background: The left ventricular (LV) summit has anatomical limitations, so the detailed mapping is difficult. Therefore, the mechanism of ventricular tachycardia (VT) originating from the LV summit is not well understood. Case summary: A 70-year-old man had VTs with right bundle branch block (VT1 and VT3) and left bundle branch block (VT2) morphologies originating from the left ventricular summit (LV summit). During the VT2 and VT3, fragmented potentials, which occurred earlier than the QRS onset, were recorded from bipolar electrodes of a catheter at the anterior intraventricular vein (AIV). By pacing from right ventricular apex, constant and progressive fusion were observed. During the entrainment pacing, the fragmented potentials in the AIV catheter were activated orthodromically and those in the His bundle were activated antidromically. In addition, there were two components of the ventricular electrogram at the LV summit area with the interval of more than 100 ms during the VTs. We performed bipolar radiofrequency ablation between the LV endocardium and AIV, and the VTs became non-inducible. Discussion: Non-sustained VT/premature ventricular contraction originating from LV summit is generally considered to occur due to abnormal automaticity or triggered activity. In contrast, using entrainment technique, we demonstrated that the VTs with multiple morphologies were sustained with a re-entrant mechanism. Fragmentated potentials recorded in the AIV catheter were activated orthodromically with the entrainment pacing, indicating the slowly conducting isthmus. The intramural VT substrate was also suggested with a prolonged conduction time between the two ventricular components during the VTs.

Improved outcomes of cardiac resynchronization therapy with a defibrillator in systolic heart failure: Analysis of the Japan cardiac device treatment registry database.

Background: Temporal change in outcomes of heart failure patients receiving cardiac resynchronization therapy with a defibrillator (CRT-D) is unknown. Methods: We assess outcomes and underlying heart diseases of patients receiving CRT-D with analyzing database of the Japan cardiac device treatment registry (JCDTR) at the implantation year 2011-2015 and New JCDTR at the implantation year 2018-2021. Results: Proportion of nonischemic heart diseases was about 70% in both the groups (JCDTR: 69%; New JCDTR: 72%). Cardiac sarcoidosis increased with the rate of 5% in the JCDTR to 9% in the New JCDTR group. During an average follow-up of 21 months, death from any cause occurred in 167 of 906 patients in the JCDTR group (18%) and 79 of 611 patients in the New JCDTR group (13%) (adjusted hazard ratio [aHR] in the New JCDTR group, 0.72; 95% confidence interval [CI]: 0.55-0.94; p = .017). The superiority was mainly driven by reduction in the risk of noncardiac death. With regard to appropriate and inappropriate implantable cardioverter-defibrillator (ICD) therapy, there was a significant reduction in the New JCDTR group versus the JCDTR group (aHR in the New JCDTR group, 0.76; 95% CI: 0.59-0.98; p = .032 for appropriate ICD therapy; aHR in the New JCDTR group, 0.24; 95% CI: 0.12-0.50; p < .0001 for inappropriate ICD therapy). Conclusions: All-cause mortality was reduced in CRT-D patients implanted during 2018-2021 compared to those during 2011-2015, with a significant reduction in noncardiac death.

Cardiac resynchronization therapy with a defibrillator in non-ischemic and ischemic patients for primary and secondary prevention of sudden cardiac death: Analysis of the Japan cardiac device treatment registry database.

Background: Panoramic studies in patients with cardiac resynchronization therapy with a defibrillator (CRT-D) focusing on the etiology and indication are scarce. Besides, a controversy exists regarding requirement of a defibrillator in non-ischemic patients for primary prevention with CRT. Methods: Annual trends of de novo CRT-D implantations from 2011 to 2020 and outcomes of those between January 2011 and August 2015 were analyzed from the Japan cardiac device treatment registry (JCDTR) and New JCDTR database. Results: From 2011 to 2020, 8062 CRT-D recipients were registered, whose dominant indication was primary prevention of sudden cardiac death with a steady rate of about 70%. There was no significant temporal change of the proportion of non-ischemic patients being about 70% and 65% for primary and secondary prevention, respectively. Non-ischemic patients for primary prevention were associated with increased odds of appropriate ICD therapy [adjusted hazard ratio (aHR): 1.66; 95% confidence interval (CI): 1.01-2.75; p = .047] and reduced odds of any death (aHR: 0.66; 95% CI: 0.44-0.99; p = .046) as compared to ischemic patients. Conclusions: Proportion of non-ischemic etiology was much higher than that of ischemic one in the CRT-D cohort. Based on the higher odds of appropriate ICD therapy, non-ischemic patients for primary prevention appear to be prudently selected in Japan.

Intravascular ultrasound findings of the protrusion of the EXOSEAL plug that caused acute limb ischemia.

Vascular closure devices have become popular for rapid hemostasis and early ambulation. However, there are a few reports of complications. We presented a case with acute limb ischemia caused by the protrusion of the EXOSEAL plug into the vessel. Intravascular ultrasound imaging helped determine the plug that caused the occlusion.

Successful Application of Stereotactic Body Radiation Therapy for Ventricular Tachycardia Substrate in a Patient With Nonischemic Cardiomyopathy.

Cardiac stereotactic body radiotherapy (SBRT) has been gaining attention as a potential treatment for patients with ventricular tachycardia (VT). Here, we describe a nonischemic patient with severe heart failure and VTs originating from the deep anteroseptal substrate that was refractory to standard and bipolar catheter ablations, and was successfully managed with SBRT. In conclusion, anteroseptal VTs resistant to catheter ablation in severe nonischemic heart failure might be an indication for cardiac SBRT as palliative therapy.

Predictors of cardiovascular mortality after an electrical storm in patients with structural heart disease.

BACKGROUND: Electrical storms (ESs) in patients with structural heart disease (SHD) have been reported to be associated with a poor prognosis. However, the detailed cause of death and influence of implantable cardioverter defibrillator (ICD) therapy in ES patients have not been fully investigated. Therefore, we sought to explore the detailed clinical course after an ES and the impact of the ICD therapy in patients with SHDs. METHODS: We retrospectively analyzed 31 consecutive patients with ESs who had undergone an ICD implantation. ESs were defined as three or more ventricular arrhythmias within 24 h. RESULTS: During a mean follow up of 4.5 years, 13 patients died. Among them, cardiovascular death (CVD) was observed in 11/13 (85%), and the leading cause of the CVD was end-stage heart failure. A New York Heart Association class ≥III at the time of the ES occurrence (HR 6.51 95% CI 1.94-25.1, p = 0.003) and any shock therapy (HR 5.94 95% CI 1.06-112.2, p = 0.04) were associated with CVD. CONCLUSION: In the current single center study, the major cause of death in ES patients with SHDs was end-stage heart failure. Any shock therapy was associated with CVD. Arrhythmia management to avoid ICD shocks might reduce the mortality in ES patients.

Dual countertraction for extraction of abandoned leads with severe lead-to-lead adhesion.

Note that firm adhesion between the atrial lead near the proximal electrode and the ventricular lead is present. Simultaneous application of countertraction from the femoral and jugular workstation, i.e. dual countertraction, liberated the two leads from the adhesion.

Electrical Storm as an Independent Mortality Risk in Patients with Preserved or Moderately Reduced Left Ventricular Function.

Electrical storm (ES), defined by 3 or more occurrences of ventricular arrhythmias within 24 hours, has been shown to be associated with an increased risk of mortality; however, detailed information remains lacking. We aimed to examine the incidence and determinants of ES and its impact on mortality in patients enrolled in the nationwide implantable cardioverter-defibrillator (ICD) registry.We studied 1,256 patients (age 65 ± 12 years) who had structural heart disease with an ICD. The patients were classified into reduced ejection fraction (EF < 35%; 657 (52%) patients) and preserved or moderately reduced EF (EF ≥ 35%; 599 (48%) patients).ES occurred in 49 (7%) and 36 (6%) patients in the EF < 35% and EF ≥ 35% groups (log-rank P = 0.297) during the median follow-up of 2.3 years. ICD with resynchronization therapy was associated with a lower incidence of ES in patients with EF < 35%. Non-ischemic heart disease and diuretics were associated with ES in patients with EF ≥ 35%. During the follow-up, 10/49 (20%) patients with ES and 80/608 patients (13%) without ES died in patients with EF < 35%, while 7/36 (19%) patients with ES and 38/563 patients (7%) without ES died in those with EF ≥ 35%. We have created 4 Cox multivariate models. All models showed approximately 2-fold higher hazard ratios in patients with EF ≥ 35% compared to EF < 35%.Our study showed that the determinants of ES differed between EF < 35% and EF ≥ 35%. The impact of ES for mortality was numerically higher in EF ≥ 35% than in EF < 35%, although a significant interaction was not detected.

A single premature stimulation from the para-Hisian region unmasked negative involvement of the left anterior fascicle in the verapamil-sensitive ventricular tachycardia with a right bundle branch block and right-axis deviation.

A 33-year-old man had verapamil-sensitive ventricular tachycardia (VT) with a right bundle branch block (RBBB) and right axis deviation. Programmed stimulation from the para-Hisian region induced ventricular tachycardias (VT1 or VT2). VT1 was entrained during pacing from the para-Hisian region. A single para-Hisian stimulation antidromically captured the proximal portion of the left anterior fascicle (LAF), but the cycle length of VT2 remained unchanged. This observation indicated that the upper limb of the LAF was a bystander of the reentry circuit. We have clarified this mechanism with applying a single premature stimulation from the para-Hisian region.

Current status and role of programmed ventricular stimulation in patients without sustained ventricular arrhythmias and reduced ejection fraction: Analysis of the Japan cardiac device treatment registry database.

BACKGROUND: The aim of this study was to clarify the current status and role of programmed ventricular stimulation in patients without sustained ventricular arrhythmias and reduced left ventricular ejection fraction (LVEF). METHODS: The follow-up data of the Japan cardiac device treatment registry (JCDTR) was analyzed in 746 patients with LVEF ≦35% and no prior history of sustained ventricular arrhythmias who underwent de novo implantable cardioverter-defibrillator (ICD) or cardiac resynchronization therapy with a defibrillator (CRT-D) implantation between January 2011 and August 2015. RESULTS: Electrophysiological study (EPS) with programmed ventricular stimulation had been performed before the device implant in 118 patients (15.8%, EPS group). During the mean follow-up of 21 ± 12 months, the rate of freedom from any death and appropriate defibrillator therapy was not significantly different between EPS group (n = 118) and No EPS group (n = 628). NYHA class II-IV, and QRS duration were negatively associated with performing EPS. Among patients in the EPS group, the rate of ventricular tachycardia (VT)/ventricular fibrillation (VF) induction was 48%. The inducibility was not a predictor of appropriate defibrillator therapy, whereas BNP ≧535 pg/mL and no use of amiodarone were significantly associated with a risk of the appropriate therapy. CONCLUSION: EPS for induction of VT/VF had been performed in about 16% of patients with reduced LVEF before primary prevention ICD/CRT-D implantation. Elevated BNP levels and no use of amiodarone, but not inducibility of VT/VF, appeared to be associated with appropriate defibrillator therapy in these populations.

SK channel blockade prevents hypoxia-induced ventricular arrhythmias through inhibition of Ca2+/voltage uncoupling in hypertrophied hearts.

Ventricular arrhythmia (VA) is the major cause of death in patients with left ventricular (LV) hypertrophy and/or acute ischemia. We hypothesized that apamin, a blocker of small-conductance Ca2+-activated K+ (SK) channels, alters Ca2+ handling and exhibits anti-arrhythmic effects in ventricular myocardium. Spontaneous hypertensive rats were used as a model of LV hypertrophy. A dual optical mapping of membrane potential (Vm) and intracellular calcium (Cai) was performed during global hypoxia (GH) on the Langendorff perfusion system. The majority of pacing-induced VAs during GH were initiated by triggered activities. Pretreatment of apamin (100 nmol/L) significantly inhibited the VA inducibility. Compared with SK channel blockers (apamin and NS8593), non-SK channel blockers (glibenclamide and 4-AP) did not exhibit anti-arrhythmic effects. Apamin prevented not only action potential duration (APD80) shortening (-18.7 [95% confidence interval, -35.2 to -6.05] ms vs. -2.75 [95% CI, -10.45 to 12.65] ms, P = 0.04) but also calcium transient duration (CaTD80) prolongation (14.52 [95% CI, 8.8-20.35] ms vs. 3.85 [95% CI, -3.3 to 12.1] ms, P < 0.01), thereby reducing CaTD80 - APD80, which denotes "Cai/Vm uncoupling" (33.22 [95% CI, 22-48.4] ms vs. 6.6 [95% CI, 0-14.85] ms, P < 0.01). The reduction of Cai/Vm uncoupling was attributable to less prolonged Ca2+ decay constant and suppression of diastolic Cai increase by apamin. The inhibition of VA inducibility and changes in APs/CaTs parameters caused by apamin was negated by the addition of ouabain, an inhibitor of Na+/K+ pump. Apamin attenuates APD shortening, Ca2+ handling abnormalities, and Cai/Vm uncoupling, leading to inhibition of VA occurrence in hypoxic hypertrophied hearts.NEW & NOTEWORTHY We demonstrated that hypoxia-induced ventricular arrhythmias were mainly initiated by Ca2+-loaded triggered activities in hypertrophied hearts. The blockades of small-conductance Ca2+-activated K+ channels, especially "apamin," showed anti-arrhythmic effects by alleviation of not only action potential duration shortening but also Ca2+ handling abnormalities, most notably the "Ca2+/voltage uncoupling."

Fast pathway ablation unmasks nodoventricular fibers in a 15-year-old patient with supraventricular tachycardia.

We described a 15-year-old boy who underwent the catheter ablation for the nodoventricular (NV) tachycardia that had difficulty in differentiation from atrioventricular nodal reentrant tachycardia with upper common pathway. The modification of the fast pathway revealed an anterograde conduction of the NV fiber. We successfully performed the catheter ablation targeting for the right ventricular insertion site of the NV fiber.

A hybrid therapy for arrhythmogenic congestive cavity in a single ventricle.

We describe a 15-year-old girl who underwent intraoperative catheter ablation for the ventricular tachycardia associated with Ebstein's anomaly with functional pulmonary atresia and a small right ventricle (RV) after Fontan surgery. The computed tomography showed the dilated right atrium and RV due to the failure of RV plication. The activation mapping revealed that the ventricular tachycardia showed a focal pattern originating from the atrialized RV (aRV). With careful preparations, the procedure of catheter ablation combined with the adjustment of Starnes fenestration and plication of RV/atrialized RV was very effective for this patient.

Higher Pulmonary Arterial Pressure Was Related to Non-Pulmonary Vein Atrial Tachyarrhythmia.

Recurrence of atrial tachyarrhythmias (ATA) following catheter ablation for atrial fibrillation (AF) is often associated with the recovery of conduction into previously isolated pulmonary veins (PVs). Little evidence concerning repeat PV isolation (PVI) and non-PV ATA ablation has been reported. This study aimed to explore the clinical outcome of recurrent ATA ablation after PVI and the difference between patients with and without non-PV ATA.A total of 49 patients without structural heart diseases who received catheter ablation for recurrent AF between January 2014 and December 2018 were recruited (prior ablation with PVI only 71.4% and PVI with cavotricuspid isthmus line ablation 28.6%). Patients were divided into two groups according to the presence or absence of non-PV ATA.Most patients (53.1%) experienced very late recurrence with a median duration of 15 months. A total of 15 patients had non-PV ATA and received non-PV ATA ablation whereas 34 patients received only repeat PVI for reconnected PVs. A higher pulmonary arterial systolic pressure (PASP) was associated with non-PV ATA (odds ratio: 1.161; 95% confidence interval: 1.021-1.321; P = 0.023). During 4.7 ± 1 months, 4/15 (26.7%) and 1/34 (2.9%) patients with and without non-PV ATA, respectively, had ATA recurrence (P = 0.011). The cumulative incidence of ATA recurrence after repeat ablation was significantly lower in patients without non-PV ATA (P = 0.013).In our study, a high PASP was associated with non-PV ATA in patients with recurrent AF. Repeat PVI had a high rate of maintenance of sinus rhythm in patients without non-PV ATA.

Retrograde sharp potential resembling the his-bundle electrogram: is this a case of atrioventricular re-entrant tachycardia involving twin atrioventricular nodes with the anterior node exhibiting only retrograde conduction?

A 2-year-old male with right isomerism was referred for supraventricular tachycardias. Atrial pacing study revealed that anterograde conduction was only through the posterior atrioventricular node. During the mapping of ventriculoatrial conduction, we identified a sharp potential resembling a His-bundle electrogram with a decremental property at the anterior wall of the common atrium. Catheter ablation for the potential eliminated the anterior ventriculoatrial conduction, thereby indicating retrograde activation of the possible anterior atrioventricular node.