The optimal slow pathway ablation site in atrioventricular nodal reentrant tachycardia cases with an inferiorly located His bundle.

INTRODUCTION: The optimal slow pathway (SP) ablation site in cases with an inferiorly located His bundle (HIS) remains unclear. METHODS AND RESULTS: In 45 patients with atrioventricular nodal reentrant tachycardia, the relationship between the HIS location and successful SP ablation site was assessed in electroanatomical maps. We assessed the location of the SP ablation site relative to the bottom of the coronary sinus ostium in the superior-to-inferior (SPSI), anterior-to-posterior (SPAP), and right-to-left (SPRL) directions. The HIS location was assessed in the same manner. The HIS location in the superior-to-inferior direction (HISSI), SPSI, SPAP, and SPRL were 17.7 ± 6.4, 1.7 ± 6.4, 13.6 ± 12.3, and -1.0 ± 13.0 mm, respectively. The HISSI was positively correlated with SPSI (R2 = 0.62; P < .01) and SPAP (R2 = 0.22; P < .01), whereas it was not correlated with SPRL (R2 = 0.01; P = .65). The distance between the HIS and SP ablation site was 17.7 ± 6.4 mm and was not affected by the location of HIS. The ratio of the amplitudes of atrial and ventricular potential recorded at the SP ablation site did not differ between the high HIS group (HISSI ≥ 13 mm) and low HIS group (HISSI < 13 mm) (0.10 ± 0.06 vs. 0.10 ± 0.06; P = .38). CONCLUSION: In cases with an inferiorly located HIS, SP ablation should be performed at a lower and more posterior site than in typical cases.

Incidence, distribution, and electrogram characteristics of endocardial-epicardial connections identified by ultra-high-resolution mapping during a left atrial posterior wall isolation of atrial fibrillation.

PURPOSE: The left atrial posterior wall (LAPW) can be a target for atrial fibrillation (AF) catheter ablation but is sometimes difficult to completely isolate due to the presence of endocardial-epicardial connections. We aimed to investigate the incidence and distribution of epicardial residual connections (epi-RCs) and the electrogram characteristics at epi-RC sites during an initial LAPW isolation. METHODS: We retrospectively studied 102 AF patients who underwent LAPW mapping before and after a first-pass linear ablation along the superior and inferior LAPW (pre-ablation and post-ablation maps) using an ultra-high-resolution mapping system (Rhythmia, Boston Scientific). RESULTS: Epi-RCs were observed in 41 patients (40.2%) and were widely distributed in the middle LAPW area and surrounding it. The sites with epi-RCs had a higher bipolar voltage amplitude and greater number of fractionated components than those without (median, 1.09 mV vs. 0.83 mV and 3.9 vs. 3.4 on the pre-ablation map and 0.38 mV vs. 0.27 mV and 8.5 vs. 4.2 on the post-ablation map, respectively; P < 0.001). Receiver operating characteristic analyses demonstrated that the number of fractionated components on the post-ablation map had a larger area under the curve of 0.847 than the others, and the sensitivity and specificity for predicting epi-RCs were 95.4% and 62.1%, respectively, at an optimal cutoff of 5.0. CONCLUSIONS: Among the patients with epi-RCs after a first-pass LAPW linear ablation, areas with a greater number of fractionated components (> 5.0 on the post-ablation LAPW map) may have endocardial-epicardial connections and may be potential targets for touch-up ablation to eliminate the epi-RCs.

Bilateral Cardiac Sympathetic Denervation for Treatment-Resistant Ventricular Arrhythmias in Heart Failure Patients with a Reduced Ejection Fraction.

The sympathetic nervous system plays an important role in life-threatening ventricular arrhythmias (VAs). Bilateral cardiac sympathetic denervation (BCSD) is performed for refractory VAs. We sought to assess our institutional experience with BCSD in managing treatment-resistant monomorphic ventricular tachycardia (MMVT) in heart failure patients with a reduced ejection fraction (HFrEF).Four patients with HFrEF (EF 30.0 ± 8.2%, New York Heart Association [NYHA] class IV 1) underwent BCSD for MMVT (VT storm 3, repetitive VT requiring implantable cardioverter defibrillator [ICD] therapy 1) refractory to antiarrhythmic drugs, catheter ablation and ICD therapy. BCSD was effective for suppressing VT in 3 patients for whom deep sedation was effective for suppressing VT. One patient remained alive after 14 months of follow-up without episodes of VT. One patient died of acute myocardial infarction before discharge and 1 patient died from unknown cause at 3 days post-discharge. In contrast, BCSD was completely ineffective for suppressing VT in a patient with NYHA class IV for whom deep sedation and stellate ganglion block were ineffective. This patient died on the 10th post-CSD day, despite left ventricular assist device implantation. In all cases, BCSD was successfully performed without procedure-related complications.Despite the limited number of cases, our results showed that BCSD in patients with HFrEF suppressed refractory MMVT in acute-phase except for a patient with NYHA class IV; however, the prognoses were not good. BCSD may be a treatment option at an earlier stage of NYHA and a bridge to orthotopic heart transplantation, even if BCSD is effective for suppressing VAs.

Antiphospholipid Syndrome Diagnosed as a Result of the Occurrence of an Ischemic Stroke After a Successful Catheter Ablation of Atrial Fibrillation and Continuous Direct Oral Anticoagulants.

We report a case of an ischemic stroke after a successful catheter ablation of atrial fibrillation (AF) and continuous oral anticoagulation therapy with direct oral anticoagulants (DOACs), which was the trigger for diagnosing antiphospholipid syndrome (APS). A 68-year-old woman underwent catheter ablation of persistent AF and continued oral anticoagulation with edoxaban at a dose of 30 mg once daily after the ablation procedure. An asymptomatic intracerebral hemorrhage was detected by brain computed tomography and magnetic resonance imaging one month post-ablation. Oral anticoagulation with dabigatran at 110 mg twice daily was continued thereafter due to a high stroke risk profile of a CHA2D2-VASc score of 3. Eight months after the procedure, the patient had multiple acute cerebral infarctions despite no apparent recurrence of atrial tachyarrhythmias and continuation of the DOAC. A blood examination revealed the presence of anti-cardiolipin-beta2-glycoproteion complex antibodies and lupus anticoagulants, and the patient was diagnosed with primary APS. The DOAC was changed to warfarin. The patient has remained free from any ischemic or hemorrhagic cerebral events for 11 months after the oral anticoagulants were changed. The ischemic stroke in the present case appeared to be associated with APS rather than AF. A diagnosis of APS may be extremely crucial in AF patients who have new-onset ischemic strokes under continuous administration of DOACs, because vitamin K antagonists are more effective for the prevention of APS-related ischemic strokes than DOACs.

Intra-carina reentrant atrial tachycardia after pulmonary vein isolation of atrial fibrillation.

A 77-year-old man underwent catheter ablation of an atrial tachycardia (AT) after a pulmonary vein (PV) isolation of atrial fibrillation. The AT appeared to be a figure-of-eight reentrant AT by high-resolution mapping: one reentrant circuit rotated clockwise within the right PV (RPV) carina and the other rotated counterclockwise via two conduction gaps along the previous RPV isolation line. However, entrainment pacing from the carina and conduction gaps suggested that the AT was an intra-carina localized reentrant AT with a passive loop around the anterior RPV isolation line via those gaps. A radiofrequency application at the RPV carina terminated the AT.

Prognostic impact of malnutrition in elderly patients with acute myocardial infarction.

We aimed to investigate the prevalence and the prognostic impact of malnutrition using the geriatric nutritional risk index (GNRI) in elderly patients with acute myocardial infarction (AMI). We investigated 130 consecutive patients aged ≥ 75 years who were discharged following successful primary coronary intervention between March 2009 and December 2016. The mean age of the patients was 81.5 ± 5.0 years, and 55.4% of them were male. At discharge, the patients' nutritional statuses were evaluated using the GNRI, which were calculated as follows: 14.89 × serum albumin (g/dL) + 41.7 × body mass index/22. The patients were divided into two groups, a low GNRI group (GNRI < 92) with nutrition-related risk and a high GNRI group (GNRI ≥ 92) without nutrition-related risk. The mean GNRI score of all patients was 95.2 ± 11.0, and 46 patients (35.4%) had a low GNRI score. During the mean follow-up of 1030 ± 850 days, the all-cause mortality was significantly higher in the low GNRI group than in the high GNRI group (32.6% vs. 13.1%, p < 0.001), while the event rates of AMI recurrence and hospitalization due to heart failure did not differ significantly between the two groups. Multivariate Cox proportional analysis revealed that low GNRI was a modest but independent predictor of mortality (hazard ratio, 0.94; 95% confidence interval 0.90-0.98; p = 0.01). Among elderly patients with AMI, malnutrition assessed using the GNRI was often encountered and was an independent predictor of long-term mortality.

Symptomatic and asymptomatic intracerebral hemorrhages detected by magnetic resonance imaging after catheter ablation of atrial fibrillation.

PURPOSE: Symptomatic intracerebral hemorrhages (ICHs) are a rare complication after atrial fibrillation (AF) catheter ablation, while the incidence of asymptomatic ICHs detected by magnetic resonance (MR) imaging remains unclear. This study aimed to investigate the incidence, characteristics, and predictors of new-onset ICHs on MR imaging after AF ablation. METHODS: We retrospectively studied 1257 consecutive AF ablation procedures in 1201 patients who underwent MR imaging on the day after the procedure. Repeat MR imaging within 3 months post-ablation was available in 352 procedures. RESULTS: Old ICHs on the initial MR imaging were observed in 28 procedures (2.2%). Post-ablation new ICHs were observed in 14 procedures (4.0%), including one symptomatic (0.3%) and 13 (3.7%) asymptomatic ICHs. One patient had a new ICH on the initial MR imaging, while the remaining 13 had such on the repeat MR imaging. A univariate analysis revealed that a previous ischemic stroke or transient ischemic attack (TIA) and the CHA2DS2-VASc score were positive predictors of new ICHs (odds ratios, 5.502 and 1.435; P = 0.004 and 0.044). The lesion diameter did not significantly differ between the old and new ICHs (median, 6.1 mm vs. 8.0 mm, P = 0.281), while the predominant location differed (lobar areas, 22.6% vs. 53.3%; cerebellum, 22.6% vs. 20.0%; others, 54.8% vs. 26.7%; P = 0.026). CONCLUSIONS: A few asymptomatic ICHs may occur after AF ablation. Most of the post-ablation new ICHs occurred a few days or later after the procedure. A previous ischemic stroke/TIA and the CHA2DS2-VASc score may be risk factors for post-ablation ICHs.

Impact of the size of non-ablated left atrial posterior wall area on outcomes after extensive encircling pulmonary vein isolation.

The aim of this study was to evaluate the impact of the size of the isolated surface area and non-ablated left atrial posterior area after extensive encircling pulmonary vein isolation (EEPVI) for non-paroxysmal atrial fibrillation (AF) on arrhythmia recurrence. This study included 132 consecutive persistent AF patients who underwent EEPVI guided by Ablation Index (AI). The isolated antral surface area (IASA) excluding the pulmonary veins, the non-ablated left atrial (LA) posterior wall surface area (PWSA), the ratio of IASA to LA surface area (IASA/LA ratio), and the ratio of PWSA to LA surface area (PWSA/LA ratio) were assessed using CARTO3 and the association with AF and atrial tachycardia (AT) recurrence was examined. At a mean follow-up of 13.2 ± 7.3 months, sinus rhythm was maintained in 115 (87%) patients. In the univariate Cox regression analysis, the factors that significantly predicted AT/AF recurrence were a history of heart failure, a higher CHA2DS2-VASc score, a larger LA diameter, and a larger PWSA/LA ratio. Multivariate Cox regression analysis revealed that the independent predictors of AT/AF recurrence were LA diameter [hazard ratio (HR) 1.120 per 1 mm increase; 95% confidence interval (CI) 1.006-1.247; P = 0.039] and PWSA/LA ratio (HR 1.218 per 1% increase; 95% CI 1.041-1.425; P = 0.014). Receiver operating characteristics curve analysis yielded an optimal cut-off value of 8% for the PWSA/LA ratio. The Kaplan-Meier survival curve showed that patients with a larger PWSA/LA ratio had poorer clinical outcomes (Log-rank P = 0.001). A larger PWSA/LA ratio was associated with a high AT/AF recurrence rate in patients with non-paroxysmal atrial fibrillation.

Determinants of Insufficient Optimal Medical Therapy after Acute Myocardial Infarction.

Objective Although the importance of evidence-based optimal medical therapy (OMT) after acute myocardial infarction (AMI) has been recognized, the prescription rate of OMT is not sufficiently high in real-word clinical settings. The purpose of this study was to identify the clinical characteristics of AMI patients who did not receive OMT. Methods The present study was a retrospective study. OMT was defined as the combination of antiplatelet therapy, angiotensin-converting enzyme (ACE) inhibitors/angiotensin II receptor blockers (ARBs), beta-blockers, and statins at the time of hospital discharge. Non-OMT was defined as the lack of either antiplatelet therapy, ACE inhibitors/ARBs, beta-blockers, or statins. Results A total of 457 AMI patients were included as the final study population, and 98 patients (22.4%) lacked at least 1 OMT medication. The prescription rates of antiplatelet therapy, ACE inhibitors/ARBs, beta-blockers, and statins were 98.7%, 87.5%, 90.4%, and 96.7%, respectively. In the multivariate logistic regression analysis, age [per 1-year increase: odds ratio (OR) 1.033, 95% confidence interval (CI) 1.007-1.059, p=0.014], hemodialysis (vs. no hemodialysis: OR 2.707, 95% CI 1.082-6.774, p=0.033), estimated glomerular filtration rate <30 mL/min/1.73 m2 without hemodialysis (OR 4.585, 95% CI 1.975-10.644, p<0.001), AMI caused by vasospastic angina (VSA) (vs. no VSA: OR 13.198, 95% CI 1.809-96.260, p=0.011), and asthma (vs. no asthma: OR 7.241, 95% CI 1.716-30.559, p=0.007) were significantly associated with non-OMT, whereas heart rate on admission (per 1-bpm increase: 0.987, 95% CI 0.975-0.999, p=0.033), any PCI (vs. no PCI: OR 0.156, 95% CI 0.066-0.373, p<0.001), and ST-elevation myocardial infarction (STEMI) (vs. NSTEMI: OR 0.384, 95% CI 0.218-0.675, p=0.001) were inversely associated with non-OMT. Conclusion An advanced age, VSA, bradycardia, asthma, impaired renal function, non-PCI revascularization, and non-ST-elevation myocardial infarction were significantly associated with non-OMT.

Prognostic impact of malnutrition assessed using geriatric nutritional risk index in patients aged ⩾80 years with heart failure.

AIMS: Malnutrition in elderly patients is one of the important issues in an aging society. We aimed to investigate the prevalence and prognostic impact of malnutrition assessed using the geriatric nutritional risk index in very elderly patients hospitalized owing to heart failure. METHODS: We enrolled 213 consecutive patients aged ⩾80 years who were hospitalized with heart failure. The mean age was 87.2 ± 4.9 years, and 43.7% of them were male. The nutritional status on admission was evaluated using the geriatric nutritional risk index, which was calculated as follows: 14.89 × serum albumin (g/dL) + 41.7 × body mass index/22. The patients were divided into two groups, a low geriatric nutritional risk index group (<92) with malnutrition risk and a high geriatric nutritional risk index group (⩾92) without malnutrition risk. RESULTS: The mean geriatric nutritional risk index of all patients was 90.7 ± 10.6, and 108 patients (50.7%) had low geriatric nutritional risk index. During the 540-day follow-up, the all-cause mortality was significantly higher in the low geriatric nutritional risk index group than in the high geriatric nutritional risk index group (35.7% vs. 12.9%, p < 0.001). The Cox proportional-hazards regression analysis revealed that low geriatric nutritional risk index was an independent predictor of mortality (hazard ratio, 2.28; 95% confidence interval, 1.15-4.49; p = 0.02). CONCLUSIONS: Low geriatric nutritional risk index on admission was common and was associated with poor prognosis in patients aged ⩾80 years who were hospitalized owing to heart failure.

Endomyocardial fibrosis and calcification in an elderly patient.

Endomyocardial fibrosis (EMF) is a rare restrictive cardiomyopathy in developed countries. The prognosis of EMF depends on severity of heart failure, and it is generally poor as there is no proven specific effective therapy. We have experienced a rare case of EMF in an elderly Japanese man.

Spontaneous Recanalization of the Obstructed Right Coronary Artery Caused by Blunt Chest Trauma.

Blunt chest trauma can cause a wide variety of injuries including acute myocardial infarction (AMI). Although AMI due to coronary artery dissection caused by blunt chest trauma is very rare, it is associated with high morbidity and mortality. In the vast majority of patients with AMI, primary percutaneous coronary interventions (PCI) are performed to recanalize obstructed arteries, but PCI carries a substantial risk of hemorrhagic complications in the acute phase of trauma. We report a case of AMI due to right coronary artery (RCA) dissection caused by blunt chest trauma. The totally obstructed RCA was spontaneously recanalized with medical therapy. We could avoid primary PCI in the acute phase of blunt chest trauma because electrocardiogram showed early reperfusion signs. We performed an elective PCI in the subacute phase when the risk of bleeding subsided. Since the risk of severe hemorrhagic complications is greater in the acute phase of blunt chest trauma as compared with the late phase, deferring emergency PCI is reasonable if signs of recanalization are observed.

Safety of Radial Access for Primary Percutaneous Intervention in Patients With ST-Elevation Acute Myocardial Infarction: Results From a Low-Volume Center.

Radial access for primary percutaneous coronary intervention (pPCI) in patients with ST-elevation acute myocardial infarction (STEMI) is recommended in high-volume experienced centers. This study investigated whether radial access for pPCI is safe even in a low-volume center. We performed radial access for pPCI in 171 patients. Major adverse cardiac events (total death, myocardial infarction, stroke) rate was 1.2%. The overall incidence of bleeding complications was 2.4%; there was no vascular complication at the access site. In patients with STEMI undergoing pPCI, the results of radial access in a low-volume center were acceptable. These findings support the safety of radial access in patients with STEMI.

Structural characterization reveals the keratinolytic activity of an arthrobacter nicotinovorans protease.

Elevated cadmium (Cd) concentrations in fishery byproducts are an environmental concern, that might be reduced by enzymatic removal and adsorption of the contaminants during recycling the byproducts as animal food. We cloned the gene for Arthrobacter nicotinovorans serine protease (ANISEP), which was isolated from the hepatopancreas of the Japanese scallop (Patiopecten yessoensis) and has been found to be an effective enzyme for Cd(II) removal. The gene is 993 bp in length and encodes 330 amino acids, including the pre (1-30) and pro (31-111) sequences. The catalytic triad consists of His, Asp, and Ser. Sequence similarities indicate that ANISEP is a extracellular serine protease. X-ray crystallography revealed structural similarities between ANISEP and the trypsin-like serine protease NAALP from Nesterenkonia sp. Site-directed mutagenesis identified Ser171 as catalytic residue. The keratinolytic activity of ANISEP was 10-fold greater than that of trypsin. ANISEP digested Cd(II)-bound recombinant metallothionein MT-10a from Laternula elliptica, but did not release Cd. These results further suggest ANISEP is a trypsin-like serine protease that can release Cd from the Japanese scallop hepatopancreas because of its strong keratinolytic activity.