Preoperative Prediction of Shock Impedance for Subcutaneous Implantable Cardioverter Defibrillator Using Chest Computed Tomography

BACKGROUND

High shock impedance is associated with conversion failure among patients with subcutaneous implantable cardioverter defibrillators (S-ICD). Currently, there is no preoperative assessment method for predicting high shock impedance. This study examined the efficacy of chest computed tomography (CT) as a preoperative evaluation tool to assess the shock impedance of S-ICDs.Methods and Results: The amount of adipose tissue adjacent to the device and anteroposterior diameter at the basal heart region were measured preoperatively using chest CT. We examined the correlation between these measurements and shock impedance at the conversion test. We enrolled 43 patients with S-ICDs (mean [±SD] age 54±15 years; body mass index 23±4 kg/m2; PRAETORIAN score 30-270 points; amount of adipose tissue 1,250±716 cm3), who underwent intraoperative conversion tests by inducing ventricular fibrillation, which was terminated with a 65-J shock. A sufficient concordance correlation coefficient was observed between the shock impedance and the amount of adipose tissue (r=0.616, P<0.01) and anteroposterior diameter (r=0.645, P<0.01). In multiple regression analysis, the amount of adipose tissue (β=0.439, P=0.009) and anteroposterior diameter (β=0.344, P=0.038) were identified as independent predictive factors of shock impedance.

CONCLUSIONS

The preoperative CT-measured amount of adipose tissue and basal heart anteroposterior diameter are independent predictors of shock impedance. These parameters may be more accurate in identifying higher shock impedance in patients with S-ICDs.

Triggers of Ventricular Fibrillation in Patients With Inferolateral J-Wave Syndrome

BACKGROUND

There are few data on ventricular fibrillation (VF) initiation in patients with inferolateral J waves.

OBJECTIVES

This multicenter study investigated the characteristics of triggers initiating spontaneous VF in inferolateral J-wave syndrome.

METHODS

A total of 31 patients (age 37 ± 14 years, 24 male) with spontaneous VF episodes associated with inferolateral J waves were evaluated to determine the origin and characteristics of triggers. The J-wave pattern was recorded in inferior leads in 11 patients, lateral leads in 3, and inferolateral leads in 17.

RESULTS

The VF triggers (n = 37) exhibited varying QRS durations (176 ± 21 milliseconds, range 119-219 milliseconds) and coupling intervals (339 ± 46 milliseconds, range 250-508 milliseconds) with a right (70%) or left (30%) bundle branch block (BBB) pattern. Trigger patterns were associated with J-wave location: left BBB triggers with inferior J waves and right BBB triggers with lateral J waves. Electrophysiologic study was performed for 22 VF triggers in 19 patients. They originated from the left or right Purkinje system in 6 and from the ventricular myocardium in 10 and were undetermined in 6. Purkinje vs myocardial triggers showed distinct electrocardiographic characteristics in coupling interval and QRS-complex duration and morphology. Abnormal epicardial substrate associated with fragmented electrograms was identified in 9 patients, with triggers originating from the same region in 7 patients. Catheter ablation resulted in VF suppression in 15 patients (79%).

CONCLUSIONS

VF initiation in inferolateral J-wave syndrome is associated with significant individual heterogeneity in trigger characteristics. Myocardial triggers have electrocardiographic features distinct from Purkinje triggers, and their origin often colocalizes with an abnormal epicardial substrate.

Revisiting predictors of worse atrioventricular valve and left ventricular systolic function following pacemaker therapy

BACKGROUND

Predictors of worsening atrioventricular valve regurgitation and left ventricular (LV) systolic function after implantation of a leadless pacemaker (LPM) remain unclear compared with those of a transvenous pacemaker (TPM).

METHODS

We retrospectively analyzed 205 patients who were newly implanted with a permanent pacemaker (119 LPMs and 86 TPMs) and underwent transthoracic echocardiography before and 8 ± 5 months after implantation. We evaluated the worsening of tricuspid and mitral regurgitation (TR and MR), defined as at least one-grade aggravation in severity, and changes in LV ejection fraction (LVEF).

RESULTS

Worsening TR occurred more frequently in the LPM group compared to the TPM group (33% vs. 20%, p = .04); however, there was no significant difference between the two groups regarding worsening MR (26% vs. 18%, p = .18) and LVEF change (-2 ± 10% vs. -3 ± 8%, p = .40). In multivariable analysis, independent predictors for worsening TR, MR, and LVEF after implantation were found to be (1) the change from sinus rhythm at baseline to atrioventricular asynchronous right ventricular (RV) pacing (odds ratio [OR]: 5.68, 95% confidence interval [CI]: 1.94-16.70, p < .01); (2) the change from non-pacing ventricular contraction at baseline to RV pacing (OR: 2.42, 95% CI: 1.12-5.24, p = .02); and (3) a higher RV pacing burden (β: -0.05, 95% CI: -0.08--0.02, p < .01), respectively.

CONCLUSION

Worsening TR, MR, and LVEF after pacemaker implantation were not associated with the type of pacing device but loss of atrioventricular synchrony or dependency on RV pacing.

Successful Epicardial Radiofrequency Ablation of Ventricular Tachycardia That Shared a Pathway with Bi-Directional Conduction in a Patient with Human Immunodeficiency Virus-Associated Cardiomyopathy

A 59-year-old man who had been diagnosed with human immunodeficiency virus-associated cardiomyopathy was referred for catheter ablation of ventricular tachycardia (VT). An electrocardiogram (ECG) waveform revealed that the clinical VT originated from the epicardium. A deceleration zone (DZ) was identified on an isochronal late activation map. Moreover, 2 forms of monomorphic VT were induced by different cycle length burst pacings from near the DZ. The morphologies of the 2 VTs with an identical cycle length were very likely to use a shared common pathway with bi-directional conduction around the slow conduction area in the left ventricle posterolateral small epicardial surface area. After ablation of the DZ, the VT was uninducible.

Two-year Outcomes of Ventricular-demand Leadless Pacemaker Therapy for Heart Block After Transcatheter Aortic Valve Replacement

Ventricular-demand leadless pacemakers (VVI-LPMs) have often been used as an alternative to atrioventricular (AV) synchronous transvenous pacemakers (DDD-TPMs) in patients with high-grade AV block following transcatheter aortic valve replacement (TAVR). However, the clinical outcomes of this unusual usage are not elucidated. Patients who received permanent pacemakers (PPMs) owing to new-onset high-grade AV block after TAVR from September 2017 to August 2020 at a high-volume center in Japan were included in the analysis, and the clinical courses of VVI-LPM and DDD-TPM implants through 2 years of follow-up were compared retrospectively. Out of 413 consecutive patients who underwent TAVR, 51 (12%) patients received a PPM. After excluding 8 patients with chronic atrial fibrillation (AF), 3 with sick sinus syndrome, and 1 with incomplete data, 17 VVI-LPMs and 22 DDD-TPMs were included in our final cohort. The VVI-LPM group had lower serum albumin levels (3.2 ± 0.5 vs. 3.9 ± 0.4 g/dL, P < .01) than the DDD-TPM group. Follow-up revealed no significant differences between the 2 groups in terms of the incidence of late device-related adverse events (0% vs. 5%, log-rank P = .38) and new-onset AF (6% vs. 9%, log-rank P = .75); however, there were increases in the rates of all-cause death (41% vs. 5%, log-rank P < .01) and heart failure rehospitalization (24% vs. 0%, log-rank P = .01) in the VVI-LPM group. This small retrospective study reveals favorable post-procedural complication rates but higher all-cause mortality with VVI-LPM compared to DDD-TPM therapy for high-grade AV block after TAVR at 2 years of follow-up.

Registry for Evaluating Healthy Life Expectancy and Long-Term Outcomes after Catheter Ablation of Atrial Fibrillation in the Very Elderly (REHEALTH AF) study: rationale and design of a prospective, multicentre, observational, comparative study

INTRODUCTION

Data are lacking on the extent to which patients with non-valvular atrial fibrillation (AF) who are aged ≥80 years benefit from ablation treatment. The question pertains especially to patients' postablation quality of life (QoL) and long-term clinical outcomes.

METHODS AND ANALYSIS

We are initiating a prospective, registry-based, multicentre observational study that will include patients aged ≥80 years with non-valvular AF who choose to undergo treatment by catheter ablation and, for comparison, such patients who do not choose to undergo ablation (either according to their physician's advice or their own preference). Study subjects are to be enrolled from 52 participant hospitals and three clinics located throughout Japan from 1 June 2022 to 31 December 2023, and each will be followed up for 1 year. The planned sample size is 660, comprising 220 ablation group patients and 440 non-ablation group patients. The primary endpoint will be the composite incidence of stroke/transient ischaemic attack (TIA) or systemic embolism (SE), another cardiovascular event, major bleeding and/or death from any cause. Other clinical events such as postablation AF recurrence, a fall or bone fracture will be recorded. We will collect standard clinical background information plus each patient's Clinical Frailty Scale score, AF-related symptoms, QoL (Five-Level Version of EQ-5D) scores, Mini-Mental State Examination (optional) score and laboratory test results, including measures of nutritional status, on entry into the study and 1 year later, and serial changes in symptoms and QoL will also be secondary endpoints. Propensity score matching will be performed to account for covariates that could affect study results.

ETHICS AND DISSEMINATION

The study conforms to the Declaration of Helsinki and the Ethical Guidelines for Clinical Studies issued by the Ministry of Health, Labour and Welfare, Japan. Results of the study will be published in one or more peer-reviewed journals.

TRIAL REGISTRATION NUMBER

UMIN000047023.

Intramural Needle Ablation for Refractory Premature Ventricular Contractions

BACKGROUND

Frequent premature ventricular contractions (PVCs) are often amenable to catheter ablation. However, a deep intramural focus may lead to failure due to inability of standard ablation techniques to penetrate the focus. We sought to assess the efficacy and safety of infusion needle ablation (INA) for PVCs that are refractory to standard radiofrequency ablation.

METHODS

Under 2 Food and Drug Administration approved protocols, INA was evaluated in patients with frequent PVCs that were refractory to standard ablation. Initial targets for ablation were selected by standard mapping techniques. INA was performed with a deflectable catheter equipped with an extendable/retractable needle at the tip that can be extended up to 12 mm into the myocardium and is capable of pacing and recording. After contrast injection for location assessment, radiofrequency ablation was performed with the needle tip using a temperature-controlled mode (maximum temperature 60 °C) with saline infusion from the needle. The primary end point was a decrease in PVC burden to <5000/24 hours at 6 months. The primary safety end point was incidence of procedure- or device-related serious adverse events.

RESULTS

At 4 centers, 35 patients (age 55.3±16.9 years, 74.2% male) underwent INA. The baseline median PVC burden was 25.4% (interquartile range, 18.4%-33.9%) and mean left ventricular ejection fraction was 37.7±12.3%. Delivering 10.3±8.0 INA lesions/patient (91% had adjunctive standard radiofrequency ablation also) resulted in acute PVC elimination in 71.4%. After a mean follow-up of 156±109 days, the primary efficacy end point was met in 73.3%. The median PVC burden decreased to 0.8% (interquartile range, 0.1%-6.0%; P<0.001). The primary safety end point occurred in 14.3% consisting of 1 (2.9%) heart block, 1 (2.9%) femoral artery dissection, and 3 (8.6%) pericardial effusions (all treated percutaneously).

CONCLUSIONS

INA is effective for the elimination of frequent PVCs that are refractory to conventional ablation and is associated with an acceptable safety profile.

REGISTRATION

URL: https://www.

CLINICALTRIALS

gov; Unique identifier: NCT01791543 and NCT03204981.

Polymorphic Ventricular Tachycardia with QT Interval Prolongation Due to a Brain Tumor

We herein report the case of a 20-year-old man with a history of epilepsy who presented with frequent transient loss of consciousness (T-LOC) and polymorphic ventricular tachycardia (VT) with QT interval prolongation. Blood investigations revealed panhypopituitarism. Following a biopsy, he was diagnosed with brain germinoma. During the biopsy, he had an episode of polymorphous VT with QT prolongation. There was no recurrence of T-LOC following chemotherapy and hormone replacement therapy. This case indicates the importance of checking the QT interval in patients with T-LOC, including those with seizures and brain tumors, to ensure appropriate treatment.

Revisit to the Prognostic Value of Premature Atrial Contraction Burden in 24-h Holter Electrocardiography for Predicting Undiagnosed Atrial Fibrillation - A Propensity Score-Matched Study

BACKGROUND

The optimum cut-off value of premature atrial contraction (PAC) burden (CV-PACb) in 24-h Holter electrocardiography (24-h ECG) for predicting atrial fibrillation (AF) is debatable, with few validation data.Methods and Results:We retrospectively analyzed 61 patients already diagnosed with AF (AD-AF) and 147 patients never diagnosed with AF (ND-AF), aged ≥50 years, free of heart disease, and who had undergone 24-h ECG and transthoracic echocardiography (TTE). Receiver operating characteristic analysis demonstrated that 0.4% was the optimal CV-PACb differentiating AD-AF from ND-AF, with 69% sensitivity and 72% specificity (area under the curve [AUC] 0.72; 95% confidence interval [CI] 0.65-0.79); however, the left atrial volume index was not significant (AUC 0.60; 95% CI 0.51-0.68). To verify the CV-PACb, new propensity-matched cohorts (i.e., subjects with a PAC burden ≥0.4% and <0.4%; n=69 in each group) were compared based on new detection of AF at a median follow-up of 50 months (interquartile range 12-60 months) Multivariable Cox regression analysis revealed that among 24-h ECG and TTE findings, only PAC burden ≥0.4% was independently associated with incident AF (hazard ratio 5.28; 95% CI 1.28-26.11; P=0.023).

CONCLUSIONS

A high PAC burden (≥0.4%) in 24-h ECG was a reliable indicator to identify undiagnosed AF, whereas TTE parameters did not show any predictive value.

Different Determinants of the Recurrence of Atrial Fibrillation and Adverse Clinical Events in the Mid-Term Period After Atrial Fibrillation Ablation

BACKGROUND

It is unclear whether there are differences in the clinical factors between atrial fibrillation (AF) recurrence and adverse clinical events (AEs), including stroke/transient ischemic attack (TIA), major bleeding, and death, after AF ablation.Methods and Results:We examined the data from a retrospective multicenter Japanese registry conducted at 24 cardiovascular centers between 2011 and 2017. Of the 3,451 patients (74.1% men; 63.3±10.3 years) who underwent AF ablation, 1,046 (30.3%) had AF recurrence and 224 (6.5%) suffered AEs (51 strokes/TIAs, 71 major bleeding events, and 36 deaths) over a median follow-up of 20.7 months. After multivariate adjustment, female sex, persistent and long-lasting persistent AF (vs. paroxysmal AF), and stepwise increased left atrial diameter (LAd) quartiles were significantly associated with post-ablation recurrences. A multivariate analysis revealed that an age ≥75 years (vs. <65 years), body weight <50 kg, diabetes, vascular disease, left ventricular (LV) ejection fraction <40% (vs. ≥50%), Lad ≥44 mm (vs. <36 mm), and creatinine clearance <50 mL/min were independently associated with AE incidences, but not with recurrences.

CONCLUSIONS

This study disclosed different determinants of post-ablation recurrence and AEs. Female sex, persistent AF, and enlarged LAd were determinants of post-ablation recurrence, whereas an old age, comorbidities, and LV and renal dysfunction rather than post-ablation recurrence were AEs determinants. These findings will help determine ablation indications and post-ablation management.

Irrigated Needle Ablation Compared With Other Advanced Ablation Techniques for Failed Endocardial Ventricular Arrhythmia Ablation

[Figure: see text].

The precordial R-prime wave: a novel discriminator between cardiac sarcoidosis and arrhythmogenic right ventricular cardiomyopathy in patients presenting with ventricular tachycardia

Funding Acknowledgements

Type of funding sources: Other. Main funding source(s): The department of cardiology from Leiden University Medical Center receives unrestricted grants from Edwards Lifesciences, Biotronik, Medtronik, Boston Scientific and BioSense Webster. MS was supported by the Research Fellowship of the European Society of Cardiology 2017/2018.

Background Cardiac sarcoidosis (CS) with right ventricular (RV) involvement may mimic ARVC. Histopathological differences may result in disease specific RV activation patterns, detectable on the 12-lead electrocardiogram (ECG). Scar in ARVC progresses from epicardium to endocardium and may lead to delayed activation of areas with reduced voltages, translating into terminal activation delay and occasionally an (epsilon) wave with small amplitude on the ECG. On the contrary, patchy transmural RV scar in CS may lead to conduction block, and therefore late activated areas with preserved voltages, reflected as preserved R’-waves in the right precordial leads.

Purpose To determine whether the terminal activation patterns in precordial leads V1-V3 distinguish CS with RV involvement from ARVC.

Methods This is a multicenter retrospective study including patients with either 1) CS with RV involvement or 2) gene-positive ARVC referred for VT ablation. A non-ventricular paced 12-lead surface ECG prior to ablation was obtained (25mm/s and 10mm/mV). For detailed analysis, Leiden ECG Analysis and Decomposition Software (LEADS) was used. After detection of QRST complexes in the spatial velocity signal, LEADS generates a representative and low-noise averaged beat. Then, measurements per lead were performed using the measurement tool in Adobe Pro DC. Based on the hypothesis that conduction block in CS will lead to late activated areas with preserved voltages, we measured the surface area (SA) of the R’-wave in V1-V3. An R’-wave was defined as any positive deflection from baseline after an S-wave.

Results 13 CS patients with RV involvement (54 ± 8years, 62% male) and 23 ARVC patients (37 ± 15years, 78% male) were included. A R’-wave in V1-V3 was present in all CS patients, compared to 11 (48%) of ARVC patients (p = 0.002). The maximum R’-wave SA in lead V1-V3 was 3.55 (IQR:2.18-5.81) mm2 in CS vs. 0.00 (IQR:0.00-0.43) mm2 in ARVC (p &lt; 0.001; Figure A). By ROC-analysis, the maximum R’-wave SA in lead V1-V3 was an excellent discriminator (area under the curve 0.980 [95%CI: 0.945-1.000]). A cutoff of ≥1.65mm2 had a sensitivity of 85% and specificity of 96% for diagnosing CS. An algorithm was created including the presence of an R’-wave in V1-V3 and the SA of this R’-wave (Figure B). This was validated in a second cohort (18 CS and 40 ARVC) with 72% sensitivity and 88% specificity.

Conclusion Transmural RV scars in CS may cause localized conduction block, leading to late activated areas with preserved voltages, reflected as large R’-wave on the 12-lead surface ECG. An easily applicable algorithm including the surface area of the largest R’-wave in lead V1-V3 ≥1.65mm2 distinguishes CS from ARVC with good sensitivity and specificity. The QRS terminal activation in precordial leads V1-V2 may reflect disease specific scar patterns (for examples: Figure C). Abstract Figure

The precordial R' wave: A novel discriminator between cardiac sarcoidosis and arrhythmogenic right ventricular cardiomyopathy in patients presenting with ventricular tachycardia

BACKGROUND

Cardiac sarcoidosis (CS) with right ventricular (RV) involvement can mimic arrhythmogenic right ventricular cardiomyopathy (ARVC). Histopathological differences may result in disease-specific RV activation patterns detectable on the 12-lead electrocardiogram. Dominant subepicardial scar in ARVC leads to delayed activation of areas with reduced voltages, translating into terminal activation delay and occasionally (epsilon) waves with a small amplitude. Conversely, patchy transmural RV scar in CS may lead to conduction block and therefore late activated areas with preserved voltages reflected as preserved R' waves.

OBJECTIVE

The purpose of this study was to evaluate the distinct terminal activation patterns in precordial leads V₁ through V₃ as a discriminator between CS and ARVC.

METHODS

Thirteen patients with CS affecting the RV and 23 patients with gene-positive ARVC referred for ventricular tachycardia ablation were retrospectively included in a multicenter approach. A non-ventricular-paced 12-lead surface electrocardiogram was analyzed for the presence and the surface area of the R' wave (any positive deflection from baseline after an S wave) in leads V₁ through V₃.

RESULTS

An R' wave in leads V₁ through V₃ was present in all patients with CS compared to 11 (48%) patients with ARVC (P = .002). An algorithm including a PR interval of ≥220 ms, the presence of an R' wave, and the surface area of the maximum R' wave in leads V₁ through V₃ of ≥1.65 mm² had 85% sensitivity and 96% specificity for diagnosing CS, validated in a second cohort (18 CS and 40 ARVC) with 83% sensitivity and 88% specificity.

CONCLUSION

An easily applicable algorithm including PR prolongation and the surface area of the maximum R' wave in leads V₁ through V₃ of ≥1.65 mm² distinguishes CS from ARVC. This QRS terminal activation in precordial leads V₁ through V₃ may reflect disease-specific scar patterns.

Risk Factors for Repeat Infection and Mortality After Extraction of Infected Cardiovascular Implantable Electronic Devices

OBJECTIVES

This study sought to investigate the factors associated with repeat infection following lead extraction procedures.

BACKGROUND

Although lead extraction is an essential therapy for patients with cardiovascular implantable electronic device (CIED) infection, repeat infection still occurs in some patients.

METHODS

The authors reviewed data for consecutive patients who underwent extraction of infected CIEDs from August 2003 to May 2019. Repeat infection was defined as infective endocarditis, sepsis with no alternative focus, or pocket infection after extraction of infected CIEDs.

RESULTS

Extraction of infected CIEDs was performed in 496 patients. The most commonly implicated pathogen was Staphylococcus aureus (188 patients). In 449 patients (90.5%), all leads were completely extracted using only transvenous techniques. Thirty-three patients (6.7%) underwent surgical lead extraction, and 14 (2.8%) had retained leads or lead components. After a median follow-up of 352 [40 to 1,255] days after CIED extraction, 144 patients (29.0%) died. Repeat infection occurred in 47 patients (9.5%) with the median time from the extraction to repeat infection of 103 [45 to 214] days. In multivariable analysis, presence of a left ventricular assist device, younger age at extraction, and S. aureus infection were independent predictors of repeat infection. Additionally, chronic kidney disease, congestive heart failure, presence of septic emboli, S. aureus infection, and occurrence of major complications were independent predictors of increased mortality.

CONCLUSIONS

Patients with S. aureus infection have a high risk of repeat infection and poor prognosis after CIED extraction. Repeat infection is also predicted by younger age and the presence of a left ventricular assist device, whereas mortality was predicted by congestive heart failure, chronic kidney disease, and septic emboli.

Periaortic Ventricular Tachycardias in Nonischemic Cardiomyopathy: Substrate and Electrocardiographic Correlations

BACKGROUND

Periaortic fibrotic ventricular tachycardia (VT) substrate is common in nonischemic cardiomyopathy (NICM), often intramural, and difficult to ablate. We sought to better characterize normal and abnormal periaortic voltage map parameters and NICM periaortic VTs.

METHODS

In 15 patients without heart disease, the 5th percentile of endocardial voltage for increasing distance from the aortic valve ring was determined. In 53 consecutive patients with NICM (64±11 years; left ventricular ejection fraction 31±10%) undergoing ablation of recurrent VT, periaortic electrogram voltage and VT characteristics were analyzed.

RESULTS

In healthy patients, the fifth percentile of the bipolar voltage increased proportional to the distance from the aortic valve ring, from 1.0 mV at 1 cm to 1.5 mV at 1.5 cm; the corresponding unipolar voltage cutoffs were 5.0 and 7.5 mV. A total of 160 VTs were induced in 53 patients with NICM, of which 28 VTs in 20 patients had periaortic origins. Periaortic VTs were associated with similar periaortic bipolar voltage, but lower UVs consistent with intramural fibrosis as an important substrate. Periaortic VTs could be divided into left and right bundle branch block forms with mapping showing right septal and lateral exits. Left bundle branch block VTs were more often acutely abolished with ablation (100% versus 69%; P=0.034), but with a 23% incidence of heart block. Greater extent of low voltage was associated with more induced VTs and worse acute outcome.

CONCLUSIONS

Adjusting voltage parameters based on distance from the aortic valve may improve definition of left ventricular outflow tract arrhythmia substrate. Periaortic VTs are common in NICM, often associated with intramural substrate and can be divided into left bundle branch block and right bundle branch block types associated with different ablation outcomes and risks.

Staphylococcus bacteremia without evidence of cardiac implantable electronic device infection

BACKGROUND

Staphylococcus bacteremia (SB) in the presence of a cardiac implantable electronic device (CIED) is frequently associated with CIED infection. In patients without clear CIED infection but SB, the role of empirical CIED removal is unclear.

OBJECTIVE

The purpose of this study was to describe the natural history of SB in the setting of a CIED and the effect of CIED removal on mortality in patients with concurrent SB without evidence of CIED infection.

METHODS

Three hundred sixty consecutive patients (mean age 61 ± 17 years; 255 (71%) men; 329 (92%) Staphylococcus aureus) with a CIED and concurrent SB were reviewed.

RESULTS

At the initial presentation with SB, 178 patients had no evidence of CIED infection. Of these, 132 (74%) had another identified source of infection. Among the 178 patients without CIED infection, 18 (10%) had empirical CIED removal during the initial bacteremia. Among those who did not undergo CIED removal, SB subsequently relapsed in 19% and relapse rates were not different for those with or without another identifiable source at the initial presentation. Relapse was strongly associated with the duration of SB >1 day (odds ratio 9.99; 95% confidence interval 3.24-30.86). Despite the absence of CIED infection, 1-year mortality was 35% and empirical device removal during the initial presentation was associated with survival benefit (hazard ratio 0.28; 95% confidence interval 0.08-0.95).

CONCLUSION

For patients with SB without evidence of CIED infection, relapse is predicted by the duration of bacteremia. Empirical CIED removal appears to be associated with a survival benefit, although there are likely clinical situations in which this could be deferred.

Clinical outcomes of ablation versus non-ablation therapy for atrial fibrillation in Japan: analysis of pooled data from the AF Frontier Ablation Registry and SAKURA AF Registry

Whether ablation for atrial fibrillation (AF) is, in terms of clinical outcomes, beneficial for Japanese patients has not been clarified. Drawing data from 2 Japanese AF registries (AF Frontier Ablation Registry and SAKURA AF Registry), we compared the incidence of clinically relevant events (CREs), including stroke/transient ischemic attack (TIA), major bleeding, cardiovascular events, and death, between patients who underwent ablation (n = 3451) and those who did not (n = 2930). We also compared propensity-score matched patients (n = 1414 in each group). In propensity-scored patients who underwent ablation and those who did not, mean follow-up times were 27.2 and 35.8 months, respectively. Annualized rates for stroke/TIA (1.04 vs. 1.06%), major bleeding (1.44 vs. 1.20%), cardiovascular events (2.15 vs. 2.49%) were similar (P = 0.96, 0.39, and 0.35, respectively), but annualized death rates were lower in the ablation group than in the non-ablation group (0.75 vs.1.28%, P = 0.028). After multivariate adjustment, the risk of CREs was statistically equivalent between the ablation and non-ablation groups (hazard ratio [HR] 0.89, 95% confidence interval [CI] 0.71-1.11), but it was significantly low among patients who underwent ablation for paroxysmal AF (HR 0.68 [vs. persistent AF], 95% CI 0.49-0.94) and had a CHA₂DS₂-VASc score  < 3 (HR 0.66 [vs. CHA₂DS₂-VASc score ≥ 3], 95% CI 0.43-0.98]). The 2-year risk reduction achieved by ablation may be small among Japanese patients, but AF ablation may benefit those with paroxysmal AF and a CHA₂DS₂-VASc score < 3.

Novel Device-Based Algorithm Provides Optimal Hemodynamics During Exercise in Patients With Cardiac Resynchronization Therapy

BACKGROUND

An adaptive cardiac resynchronization therapy (aCRT) algorithm has been described for synchronized left ventricular (LV) pacing and continuous optimization of cardiac resynchronization therapy (CRT). However, there are few algorithmic data on the effect of changes during exercise.Methods and Results:We enrolled 27 patients with availability of the aCRT algorithm. Eligible patients were manually programmed to optimal atrioventricular (AV) and interventricular (VV) delays by using echocardiograms at rest or during 2 stages of supine bicycle exercise. We compared the maximum cardiac output between manual echo-optimization and aCRT-on during each phase. After initiating exercise, the optimal AV delay progressively shortened (P<0.05) with incremental exercise levels. The manual-optimized settings and aCRT resulted in similar cardiac performance, as demonstrated by a high concordance correlation coefficient between the LV outflow tract velocity time integral (LVOT-VTI) during each exercise stage (Ex.1: r=0.94 P<0.0008, Ex.2: r=0.88 P<0.001, respectively). Synchronized LV-only pacing in patients with normal AV conduction could provide a higher LVOT-VTI as compared with manual-optimized conventional biventricular pacing at peak exercise (P<0.05).

CONCLUSIONS

The aCRT algorithm was physiologically sound during exercise by patients.

Comparing pig breeds with genetically low and high backfat thickness: differences in expression of adiponectin, its receptor, and blood metabolites

Here we characterized gene expressions in subcutaneous adipose tissue and blood metabolites of pigs with genetically low backfat (Landrace) and high backfat (Meishan). As pigs aged from 1 wk-to 3-mo old, mRNA levels of adipose-specific genes increased, although their gene expressions coding for major enzymes involved in lipid metabolism (lipoprotein lipase, fatty acid synthase, and hormone-sensitive lipase) did not differ between lean and fat pigs. Instead, there were significant effects for adiponectin and its receptor AdipoR1 mRNA levels between the two breeds of which respective expressions were lower and higher in Meishan by 3 mo of age. Contrary to changes in gene expressions, the concentrations of blood glucose, triglyceride (TG), and NEFA in both breeds decreased during growth, and 3-mo-old Meishan evidenced lower glucose with higher TG than the Landrace. The homeostasis model assessment insulin resistance (HOMA-IR) index was also calculated from the measurements of fasting glucose and insulin concentration, and Meishan showed a higher value than the Landrace. We next examined these differences in Landrace and Meishan crossbreds, which were phenotypically distinguishable by the backfat thickness as the former lean type and the latter fat type. As with the purebreds, high backfat Meishan crosses showed the characteristics of lower glucose and higher TG in circulating levels and also lower adiponectin transcripts in subcutaneous adipose tissue. Collectively, our results demonstrate that levels of adiponectin and its receptor gene expressions, blood glucose, blood lipids, and HOMA-IR in pigs vary between lean and fat. These observations strongly suggest the possibility that overall metabolic differences rather than adipocyte ability itself contribute to the fatness of genetically high backfat pigs.

Detection of high-frequency artifact as a function of pulse generator algorithms and outer-insulation material

BACKGROUND

A high rate of malfunction, predominantly intermittent high-frequency artifacts (HFAs), has been recently reported in Abbott Medical Tendril pacing leads.

OBJECTIVE

To investigate the factors associated with the occurrence of HFAs on Tendril leads using a commonly used comparator lead for a control.

METHODS

We reviewed institutional data for Medtronic CapSureFix 5076 and Abbott Medical Tendril pace-sense leads retrospectively. Recordings deemed to be due to electromagnetic interference and far-field oversensing were not included in the classification of HFAs.

RESULTS

A total of 7673 leads were analyzed: 1628 Optim-insulated Tendril leads, 825 non-Optim Tendril leads, and 5220 CapSureFix 5076. HFAs were seen in 212 leads and were more frequently observed in Tendril compared to CapSureFix leads during a mean follow-up of 4.1 ± 3.6 years. Lower age at implant, defibrillator systems, atrial position, and connection to an Abbott Medical generator were associated with increased HFA. In multivariable analysis, only connection to Abbott Medical generators (odds ratio 7.686, P < .001) and age (odds ratio 0.988 per year, P = .016) were independently associated with HFAs on pace-sense leads. In an Abbott-generator-only analysis, Optim-insulated Tendril leads were more likely to display HFAs than non-Optim Tendril leads but not Medtronic CapSureFix 5076 leads.

CONCLUSION

Abbott Medical pulse generators independently predict HFA in Tendril and CapSureFix 5076 leads, likely the result of displaying short or low-amplitude noise episodes that other devices do not record. When restricted to Abbott generators only, Optim-insulated Tendril leads show an increased incidence of HFAs when compared to non-Optim Tendril leads but not CapSureFix 5076 leads.

Development of Heart Failure From Transient Atrial Fibrillation Attacks in Responders to Cardiac Resynchronization Therapy

OBJECTIVES

This study aimed to clarify the clinical impact of transient atrial fibrillation (AF) attacks themselves and the efficacy of cardiac resynchronization therapy (CRT) in patients with intermittent AF.

BACKGROUND

The benefit of CRT in patients with intermittent AF, especially the effect of the AF attacks themselves, remains unclear.

METHODS

Among our cohort of 269 consecutive CRT patients, we compared the percent of biventricular pacing (BIVP%) and other clinical characteristics between patients with intermittent AF and those with sinus rhythm (SR).

RESULTS

During a median follow-up of 942 days (interquartile range: 379 to 1,464 days) a total of 22 patients, including 59% of CRT responders, developed heart failure (HF) due to a transient AF attack itself, and that accounted for 21% of all HF events. The BIVP% during the AF attacks was significantly lower than that during SR (p < 0.05). When compared to the SR groups, patients with intermittent AF had a significantly higher risk of developing HF or death (hazard ratio: 2.2; 95% confidence interval: 1.3 to 3.8). However, the patients who received a BIVP% of ≥90% during AF attacks were comparable to those with SR (hazard ratio: 1.2; 95% confidence interval: 0.4 to 3.0).

CONCLUSIONS

A substantial number of patients developed HF due to transient AF attacks themselves even in the CRT responders, and the reason was mainly due to the loss of the BIVP%.

Causes of Ineligibility for Recipients in Living Kidney Transplantation

BACKGROUND

Even if a living donor candidate exists, there are some cases that do not result in kidney transplantation (KTx) due to problems on the recipient side. The aim of this study was to clarify causes of ineligibility for KTx in these cases, so as to make RTx more applicable for patients.

METHODS

We targeted 470 patients with end-stage renal disease who applied for the primary kidney KTx from 2010 to 2012. Then we selected those who were not applicable for KTx and investigated recipient causes of ineligibility for KTx or not receiving KTx.

RESULTS

The average age of recipients was 47.6 ± 12.9 (7-82) years. A majority of the 470 patients were male (n = 305, 64.9%). Two hundred ninety-seven patients intended to receive a living donor KTx and the others hoped for a deceased donor KTx. Of the 297 patients, 207 (70.0%) underwent KTx and 9 (1.9%) were being prepared for KTx at the time of the survey. Eighty-three patients (27.9%) did not receive a living KTx, with 59 of these due to recipient-related problems and 30 due to donor-related problems. We further classified the reasons for these 59 recipients not undergoing KTx as follows: (1) unclear reasons (35.6%); (2) insufficient intention to receive transplant (13.6%); (3) heart disease (10.2%); (4) malignancy (8.5%); (5) immunologic risks (5.1%); (6) death during the waiting period (5.1%); (7) cerebrovascular events (5.1%); (8) cardiovascular problems (5.1%); (9) psychiatric disorders (3.4%); and (10) infections (3.4%).

CONCLUSION

Nearly 50% of the reasons for ineligibility as a recipient were related to their intention to receive KTx, with 94.9% of the nontransplanted cases due to nonimmunologic reasons. Thanks to the recent advances in immunosuppressive therapy, there were only 3 patients who could not undergo KTx due to immunologic risks. Based on these results, transplant surgeons should not only emphasize physical evaluation but should also pay careful attention to the recipient's intention to receive KTx.

Change in QRS morphology as a marker of spontaneous elimination in verapamil-sensitive idiopathic left ventricular tachycardia

BACKGROUND

Verapamil-sensitive idiopathic left ventricular tachycardia (verapamil-ILVT) is thought to be due to a reentry within the LV fascicular system. Radiofrequency catheter ablation (RFCA) is effective for elimination of the VT; however, a long-term prognosis of patients with verapamil-ILVT is still unclear.

METHODS AND RESULTS

Eighty consecutive verapamil-ILVT patients (62 men, 31 ± 12 years of age, LVEF: 65 ± 4%) were enrolled. Seventy-six (95%) cases of VT involved right bundle branch block and left axis deviation. We retrospectively analyzed changes in the QRS duration (ΔQRS-d) and QRS axis (ΔQRS-axis) during follow-up and compared them with recurrence of VT. During a mean follow-up period of 10 years (2-32 years), no sudden death or heart failure occurred. Fifty-one (64%) patients underwent RFCA, and 46 (90%) of them had no VT without any medication after RFCA. The ΔQRS-d (16 ± 2 vs. 8 ± 1 ms, P = 0.24) and ΔQRS-axis (20 ± 4 vs. 4 ± 3 degrees, P = 0.23) were not different in patients with no VT (VT[-]) and those with recurrence of VT (VT[+]). However, in the remaining 29 patients without RFCA, VT was spontaneously eliminated in 16 patients. The ΔQRS-d (30 ± 6 vs. 6 ± 1 ms, P = 0.002) and ΔQRS-axis (23 ± 4 vs. 5 ± 2 degrees, P = 0.001) were significantly larger in VT(-) patients compared to VT(+) patients during follow-up.

CONCLUSIONS

Some verapamil-ILVT patients who show QRS morphology changes over the follow-up period may become free from VT without any invasive or pharmacological treatments, suggesting that further altered LV fascicular conduction might eliminate the reentry of verapamil-ILVT.

Chronic obstructive pulmonary disease and β-blocker treatment in Asian patients with heart failure

Aims

Chronic obstructive pulmonary disease (COPD) and heart failure (HF) are increasingly frequent in Asia and commonly coexist in patients. However, the prevalence of COPD among Asian patients with HF and its impact on HF treatment are unclear.

Methods and results

We compared clinical characteristics and treatment approaches between patients with or without a history of COPD, before and after 1:2 propensity matching (for age, sex, geographical region, income level, and ethnic group) in 5232 prospectively recruited patients with HF and reduced ejection fraction (HFrEF, <40%) from 11 Asian regions (Northeast Asia: South Korea, Japan, Taiwan, Hong Kong, and China; South Asia: India; Southeast Asia: Thailand, Malaysia, Philippines, Indonesia, and Singapore). Among the 5232 patients with HFrEF, a history of COPD was present in 8.3% (n = 434), with significant variation in geography (11.0% in Northeast Asia vs. 4.7% in South Asia), regional income level (9.7% in high income vs. 5.8% in low income), and ethnicity (17.0% in Filipinos vs. 5.2% in Indians) (all P < 0.05). Use of mineralocorticoid receptor antagonists and diuretics was similar between groups, while usage of all β‐blockers was lower in the COPD group than in the non‐COPD group in the overall (66.3% vs. 79.9%) and propensity‐matched cohorts (66.3% vs. 81.7%) (all P < 0.05). A striking exception was the Japanese cohort in which β‐blocker use was high in COPD and non‐COPD patients (95.2% vs. 91.2%).

Conclusions

The prevalence of COPD in HFrEF varied across Asia and was related to underuse of β‐blockers, except in Japan.

Prognostic impact of chronic total coronary occlusion on long-term outcomes in implantable cardioverter-defibrillator recipients with ischaemic heart disease

Aims

The prognostic impact of chronic total coronary occlusion (CTO) on implantable cardioverter-defibrillator (ICD) recipients remains unclear.

Methods and results

Eighty-four consecutive patients with ischaemic heart disease who received ICD therapy for primary or secondary prevention were analysed. We investigated all-cause mortality and major adverse cardiac events (MACEs) including cardiac death, appropriate device therapy, hospitalization for heart failure, and ventricular assist device implantation. Of the study patients (mean age 70 ± 8 years; 86% men), 34 (40%) had CTO. There were no significant differences in age, left ventricular ejection fraction (LVEF), New York Heart Association functional class III or IV status, and proportion who underwent secondary prevention between patients with CTO (CTO group) and without CTO (non-CTO group). During a median follow-up of 3.8 years (interquartile range 2.7-5.4 years), the CTO group tended to have a higher MACE rate (log-rank P = 0.054) than the non-CTO group. Within the CTO group, there was no difference in the MACE rate between patients with and without viable myocardium. In patients with ICD for secondary prevention (n = 47), 16 patients (34%) with CTO had a higher MACE rate than patients without CTO (log-rank P < 0.01). Cox proportional hazards regression analysis showed that the presence of CTO, but not LVEF, was associated with a higher MACE rate. Multivariate analysis showed that the presence of CTO was a predictor of MACE (P < 0.05).

Conclusion

In patients with ischaemic heart disease receiving ICD implantation, the presence of CTO has an adverse impact on long-term prognosis, especially as secondary prevention.

Long-Term Outcomes in Kidney Transplantation From Expanded-Criteria Donors After Circulatory Death

The number of recipients waiting for a transplant is increasing. In Japan, there is more frequent use of organs from expanded-criteria donors (ECDs) after circulatory death. We retrospectively analyzed long-term outcomes of kidney transplantation (KT) from expanded-criteria donation after circulatory death (DCD). From 1995 to 2013, 97 cases of KT from DCD donors were performed in our department. Death-censored graft survival rates of ECD kidneys (n = 50) versus standard-criteria deceased-donor (SCD) kidneys (n = 47) for 1, 5, and 10 years after transplantation were 84.0% vs 97.9%, 74.8% vs 95.6%, and 70.2% vs 81.8%, respectively. No significant difference was found between the 2 groups (P = .102). Kidneys from donors with a history of hypertension (HTN) and cerebrovascular events (CVE) and contribution from older donors had significantly lower 10-year graft survival rates (P values of .010, .036, and .050, respectively). Cox proportional hazard regression analyses showed donor age to be significantly associated with long-term graft survival independently from other factors. These results suggest that ECD kidneys remain an acceptable alternative to dialysis under certain conditions. Increased donor age was a significant risk factor determining long-term graft function. Moreover, comorbidities of HTN and CVE could become significant risk factors, especially in older donors.

Endocardial and epicardial focal activation pattern due to microreentry ventricular tachycardia in a patient with cardiac sarcoidosis

Majority of ventricular tachycardias (VTs) are caused by scar‐related macroreentry in patients with cardiac sarcoidosis. These VTs usually exhibit the reentry circuit on electroanatomic maps. We here describe a rare case of VT that exhibits a focal activation pattern on the electroanatomic map despite reentrant VT.

Risk factors associated with bleeding after multi antithrombotic therapy during implantation of cardiac implantable electronic devices

Previous studies showed that continuous anticoagulation or single antiplatelet therapy during implantations of cardiac implantable electronic devices (CIED) was relatively safe. However, the safety of continuous multi antithrombotic therapy (AT) in patients undergoing CIED interventions has not been clearly defined. We sought to evaluate the safety of this therapy during CIED implantations. A total of 300 consecutive patients (mean 69 years old, 171 males) with CIED implantations were enrolled in this study. The patients were divided into 6 groups [No-AT, oral anticoagulant therapy (OAT), single antiplatelet therapy (SAPT), OAT and SAPT, dual antiplatelet therapy (DAPT), triple AT (TAT)], and the perioperative complications were evaluated. Clinically significant pocket hematomas (PH) were defined as PH needing surgical intervention, prolonged hospitalizations, interruption of AT, or blood product transfusions. There were 129, 89, 49, 20, 10, and 3 patients in No-AT, OAT, SAPT, OAT + SAPT, DAPT, and TAT groups, respectively. The occurrence of clinically significant PH and thromboembolism did not differ among 6 groups (p = 0.145 and p = 0.795, respectively). However, high HAS-BLED score and valvular heart disease (VHD) were associated with clinically significant PH (p = 0.014 and p = 0.015, respectively). Continuous multi AT may be tolerated, but patients with high HAS-BLED score or VHD would require a careful attention during CIED implantations.

Age-related changes in cortical and trabecular bone mineral status: A quantitative CT study in lumbar vertebrae

Purpose: To investigate the age and sex dependence of the bone mineral status of human lumbar vertebrae with special regard to differences between cortical and trabecular bone.

Material and Methods: The study group comprised 125 normal Japanese healthy volunteers (54 males and 71 females), and was subdivided into adult male and female groups (subjects younger than 40 years), intermediate male and female groups (ages ranging between 41 and 64 years) and old male and female groups (subjects older than 65 years). The cortical bone mineral status was estimated using a single-energy quantitative CT (SE-QCT) technique, whereas trabecular bone mineral density (BMD) was estimated using a dual-energy (DE-QCT) technique.

Results: A considerable gender difference in the age-related cortical bone status was found. There was a significant reduction of the mean values of the cortical volume and BMD in the old female group compared with those obtained in the old male group.

Conclusion: The results suggest that in men, cortical and trabecular bone volume decrease very little with age. In women, cortical volume and BMD and trabecular BMD decrease with age while trabecular bone volume does not. The study showed that all variables had higher values in men than in women and that the difference increased with age.

Catecholaminergic Polymorphic Ventricular Tachycardia (CPVT) Associated With Ryanodine Receptor (RyR2) Gene Mutations - Long-Term Prognosis After Initiation of Medical Treatment

BACKGROUND

The long-term prognosis of cardiac ryanodine receptor (RyR2) positive catecholaminergic polymorphic ventricular tachycardia (CPVT) patients after initiation of medical therapy has not been well investigated. This study aimed to assess the recurrence of fatal cardiac event after initiation of medical therapy inRyR2-positive CPVT patients.

METHODS AND RESULTS

Thirty-fourRyR2-positive CPVT patients with a history of cardiac events were enrolled. All patients had medical treatment initiated after the first symptom or diagnosis. Exercise stress tests (ESTs) were performed to evaluate the efficacy of the medical therapy. Even after the initiation of medical therapy, high-risk ventricular arrhythmias (VAs), including premature ventricular contraction couplets, bigeminy, and ventricular tachycardia, were still induced in the majority of patients (80.6%). During 7.4 years of follow-up after the diagnosis, 7 of the 34 (20.6%) patients developed fatal cardiac events. Among those 7 patients, 6 (85.7%) were not compliant with either exercise restriction or medication therapy at the time of the events.

CONCLUSIONS

Even after initiation of medical treatment, high-risk VAs were induced during EST in mostRyR2-positive CPVT patients. Most fatal recurrent cardiac events occurred in patients who were noncompliant with exercise restriction and/or medical therapy. Medical management including strict exercise restriction should be emphasized to prevent recurrent cardiac event in mostRyR2-positive CPVT patients. (Circ J 2016; 80: 1907-1915).

Clinical impact of increasing left ventricular pacing output in cardiac resynchronization therapy - the new optimization strategy

We report a patient who did not improve after standard optimization of atrioventricular and intraventricular pacing timing, but showed response to cardiac resynchronization therapy (CRT) after increasing left ventricular (LV) pacing output. Increasing LV pacing output is one of the useful optimization methods for CRT nonresponder.

A clinical and ultrasonographic study of risk factors for elbow injury in young baseball players

PURPOSE

To determine the risk factors for elbow injury and its association with glenohumeral internal rotation deficit among young baseball players.

METHODS

229 baseball players aged 9 to 14 (mean, 11) years completed a self-administered questionnaire with items related to years of playing baseball, hours of training per weekday, days of training per week, and past and present experience of elbow pain. Two orthopaedic surgeons measured the range of motion of both shoulders and elbows. Another 2 orthopaedic surgeons performed ultrasonography to detect any elbow abnormality such as fragmentation of the medial epicondylar apophysis and osteochondritis dissecans of the capitellum. Using univariate and multivariable analyses, participants with or without elbow abnormality were compared to determine the risk factors for elbow abnormality.

RESULTS

Elbow abnormality was detected in 100 of the participants and comprised osteochondritis dissecans of the capitellum (n=18) and fragmentation of the medial epicondylar apophysis (n=82). Elbow abnormality was associated with being a pitcher, past and present experience of elbow pain, loss of elbow extension, and the side-to-side internal rotation difference. The 100 participants with elbow abnormality were stratified into symptomatic (n=57) or asymptomatic (n=43) of elbow pain. Those with elbow abnormality and elbow pain was associated with being a pitcher.

CONCLUSION

Being a pitcher was a risk factor for both elbow abnormality and elbow pain. Nonetheless, 43% of baseball players with elbow abnormality were asymptomatic. The use of ultrasonography was effective in detecting elbow abnormality and enabling early treatment.

Drop episodes improved after tracheotomy: a case of Coffin-Lowry syndrome associated with obstructive sleep apnea syndrome

Some cases of Coffin-Lowry syndrome recognized episodic drops and it tended to be intractable for medical treatment. We reported here a patient with the Coffin-Lowry syndrome associated with obstructive sleep apnea syndrome (OSAS). The patient had epileptic seizures and drop attacks only during night-time and it was not recognized during the daytime. His sleep-induced electroencephalogram was normal. At 12-years old of his age, his OSAS was worse, so we performed a tracheotomy. Notably after the operation, his epileptic episodes were disappeared.