Effect of adaptive cardiac resynchronization therapy in heart failure patients with pacemaker dependency.

BACKGROUND: An adaptive cardiac resynchronization therapy (aCRT) algorithm allows continuous adjustments of pacing timings of atrioventricular delays by periodic automatic evaluation of electrical conduction. This applies to patients with an atrioventricular block and is effective in cardiac resynchronization therapy (CRT) devices; however, whether this algorithm benefits patients with pacemaker dependency is uncertain. METHODS: This study examined the clinical impact of an aCRT algorithm in patients diagnosed with heart failure with reduced ejection fraction and pacemaker dependency. A total of 359 patients underwent CRT between January 2016 and December 2022. Patients undergoing pacemaker-dependent CRT with the aCRT algorithm function were selected. Sixty-four patients with pacemaker dependency (31 with aCRT algorithm and 33 without) were included. Pacemaker dependency was defined as the absence of spontaneous ventricular activity during the sensing test at VVI 30 bpm or prolonged atrioventricular delay (> 300 ms). The primary endpoint was the composite clinical outcome of all-cause death or hospitalization for heart failure. RESULTS: No significant differences were observed in baseline characteristics between groups. During a median follow-up of 1,067 days (interquartile range 553-1,776 days), aCRT reduced the risk of composite clinical outcomes in patients with pacemaker dependency (log-rank P = 0.028). In addition, using the aCRT algorithm was an independent predictor of the composite clinical outcomes in the multivariate analysis (hazard ratio 0.34, 95% confidence interval: 0.12-0.94, P = 0.038). CONCLUSION: The aCRT algorithm significantly reduced the risk of adverse clinical outcomes in patients with pacemaker dependency. This algorithm may be an important tool for managing such patients.

Evaluation of synchronized left ventricular pacing rate over biventricular pacing in cardiac resynchronization therapy.

BACKGROUND: The adaptive cardiac resynchronization therapy (aCRT) algorithm enables synchronized left ventricular pacing (sLVP) to achieve fusion with intrinsic right ventricular activation. Although sLVP presents benefits over biventricular pacing, the adequate sLVP rate for better clinical outcomes remains unclear. We aimed to assess the association between sLVP rates and clinical outcomes. METHODS: Our study cohort included 271 consecutive patients, who underwent CRT implantation between April 2016 and August 2021. RESULTS: We evaluated 63 patients on whom we applied the aCRT algorithm [48 men, mean age: 64 ±â€¯14 years; median follow-up period: 316 days (interquartile range: 212-809 days)]. At the 6-month follow-up after CRT implantation, the frequency of CRT responders was 71 % (n = 45). The sLVP rate was significantly higher in responders than in non-responders (75 ±â€¯30 % vs. 47 ±â€¯40 %, p = 0.003). Receiver operating characteristics curve analysis revealed that the optimal cut-off value during the sLVP rate was 59.4 % for the prediction of CRT responders (area under the curve, 0.70; sensitivity, 80 %; specificity, 61 %; positive predictive value, 84 %; and negative predictive value, 55 %). Kaplan-Meier analysis demonstrated that the higher-sLVP group (sLVP ≧59.4 %, n = 43) had a better prognosis (cardiac death and heart failure hospitalization) than the lower-sLVP group (sLVP <59.4 %, n = 20) (log-rank p < 0.001). Multivariate Cox hazard analysis revealed that a higher sLVP rate was associated with a good prognosis (p < 0.001). CONCLUSIONS: sLVP was associated with CRT response, and a higher sLVP rate (≧59.4 %) was important for good prognosis in patients with aCRT.

Systematic observation-based diagnosis of atrioventricular nodal reentrant tachycardia with a bystander concealed nodoventricular pathway.

Background: This study aimed to establish a systematic method for diagnosing atrioventricular nodal reentrant tachycardia (AVNRT) with a bystander concealed nodoventricular pathway (cNVP). Methods: We analyzed 13 cases of AVNRT with a bystander cNVP, 11 connected to the slow pathway (cNVP-SP) and two to the fast pathway (cNVP-FP), along with two cases of cNVP-related orthodromic reciprocating tachycardia (ORT). Results: The diagnostic process was summarized in three steps. Step 1 was identification of the presence of an accessory pathway by resetting the tachycardia with delay (n = 9) and termination without atrial capture (n = 4) immediately after delivery of a His-refractory premature ventricular contraction (PVC). Step 2 was exclusion of ORT by atrio-His block during the tachycardia (n = 4), disappearance of the reset phenomenon after the early PVC (n = 7), or dissociation of His from the tachycardia during ventricular overdrive pacing (n = 1). Moreover, tachycardia reset/termination without the atrial capture (n = 2/2) 1 cycle after the His-refractory PVC was specifically diagnostic. Exceptionally, the disappearance of the reset phenomenon was also observed in the two cNVP-ORTs. Step 3 was verification of the AVN as the cNVP insertion site, evidenced by an atrial reset/block preceding the His reset/block in fast-slow AVNRT with a cNVP-SP and slow-fast AVNRT with a cNVP-FP or His reset preceding the atrial reset in slow-fast AVNRT with a cNVP-SP. Conclusion: AVNRT with a bystander cNVP can be diagnosed in the three steps with few exceptions. Notably, tachycardia reset/termination without atrial capture one cycle after delivery of a His-refractory PVC is specifically diagnostic.

Local dispersion of repolarization in the occurrence of ventricular fibrillation in Brugada syndrome: Possibility of phase 2 reentry?

To date, there have been no reports of recording epicardial electrograms at the onset of spontaneous ventricular fibrillation (VF) in patients with Brugada syndrome (BrS). In the case of BrS, unipolar and bipolar electrogram recording on the right ventricular epicardium revealed that dispersion of repolarization with delayed potential was associated with spontaneous occurrence of VF. Phase 2 reentry associated with shortening and dispersion of action potential could have been recorded for the first time in BrS. Epicardial unipolar mapping can guide accurate and appropriate ablation for the elimination of arrhythmia substrate in J wave syndrome.

Implications of ventricular arrhythmia after cardiac resynchronization therapy.

BACKGROUND: Conflicting data are available on whether ventricular arrhythmia (VA) or shock therapy increases mortality. Although cardiac resynchronization therapy (CRT) reduces the risk of VA, little is known about the prognostic value of VA among patients with CRT devices. OBJECTIVES: The purpose of this study was to evaluate the implications of VA as a prognostic marker for CRT. METHODS: We investigated 330 CRT patients within 1 year after CRT device implantation. The primary endpoint was the composite endpoint of all-cause death or hospitalization for heart failure. RESULTS: Forty-three patients had VA events. These patients had a significantly higher risk of the primary endpoint, even among CRT responders (P = .009). Fast VA compared to slow VA was associated with an increased risk of the primary endpoint (hazard ratio [HR] 2.14; 95% confidence interval [CI] 1.06-4.34; P = .035). Shock therapy was not associated with a primary endpoint (shock therapy vs antitachycardia pacing: HR 1.49; 95% CI 0.73-3.03; P = .269). The patients with VA had a lower prevalence of response to CRT (23 [53%] vs 202 [70%]; P = .031) and longer left ventricular paced conduction time (174 ± 23 ms vs 143 ± 36 ms; P = .003) than the patients without VA. CONCLUSION: VA occurrence within 1 year was related to paced electrical delay and poor response to CRT. VA could be associated with poor prognosis among CRT patients.

Clinical Significance of Atrial Tachyarrhythmia Duration for Ventricular Arrhythmia in Patients With Cardiac Resynchronization Therapy.

BACKGROUND: Atrial tachyarrhythmias (ATAs) are reportedly associated with ventricular arrhythmias (VAs). However, little is known about the association between ATA duration and the risk of VA. We investigated the relationship between ATA duration and subsequent VA in patients with a cardiac resynchronization therapy defibrillator (CRT-D).Methods and Results: We investigated associations between the longest ATA duration during the first year after cardiac resynchronization therapy (CRT) implantation and VA and VA relevant to ATA (VAATA) in 160 CRT-D patients. ATAs occurred in 63 patients in the first year. During a median follow-up of 925 days from 1 year after CRT implantation, 40 patients experienced 483 VAs. Kaplan-Meier analysis showed a significantly higher risk of VA in patients with than without ATA in the first year (log rank P=0.0057). Hazard ratios (HR) of VA (HR 2.36, 2.10, and 3.04 for ATA >30s, >6 min and >24 h, respectively) and only VAATA (HR 4.50, 5.59, and 11.79 for ATA >30s, >6 min and >24 h, respectively) increased according to the duration of ATA. In multivariate analysis, ATA >24 h was an independent predictor of subsequent VA (HR 2.42; P=0.02). CONCLUSIONS: Patients with ATA >24 h in the first year after CRT had a higher risk of subsequent VA and VAATA. The risk of VA, including VAATA, increased with the longest ATA duration.

Fatal Arrhythmic Risks in Cardiac Sarcoidosis With Mildly Impaired Cardiac Function.

Background: The prognosis and later fatal arrhythmia in cardiac sarcoidosis (CS) with relatively preserved cardiac function were unclear. Objectives: This study aimed to evaluate the prognosis and arrhythmic events in patients with CS and mildly impaired cardiac function. Methods: Data were collected from a nationwide Japanese cohort survey conducted in 57 hospitals (n = 420); 322 patients with CS with left ventricular ejection fraction (LVEF) >35% were investigated. Results: Ventricular tachycardia (VT) manifestation was present in 50 patients (16%) and absent in 272 (84%), of whom 36 (72%) and 46 (17%), respectively, had an implantable cardioverter-defibrillator (ICD). Over a median of 5 years, 23 all-cause deaths and 31 appropriate ICD discharges were observed. In Kaplan-Meier analysis, all-cause death did not differ between patients with and without VT manifestation (P = 0.660), although appropriate ICD therapy was significantly less used in patients without VT manifestation than in those with VT manifestation (P < 0.001). Of the 272 patients without VT manifestation, 18 had ventricular arrhythmic events (VAEs), including 3 sudden cardiac deaths and 15 appropriate ICD discharges. In multivariate analysis, concomitant nonsustained ventricular tachycardia (NSVT) with atrioventricular block (AVB), lower LVEF, abnormal gallium-67 scintigraphy or 18F-fluorodeoxyglucose positron emission tomography of the heart (Ga/PET), and concomitant NSVT with abnormal Ga/PET at CS diagnosis were independent predictors of VAEs (P = 0.008, P = 0.021, P = 0.049, and P = 0.024, respectively). Conclusions: If concomitant NSVT with AVB, concomitant NSVT with abnormal Ga/PET, or abnormal Ga/PET is observed in patients with CS and mildly impaired cardiac function (LVEF >35%), ICD should be considered as primary prevention.

N-terminal pro atrial natriuretic peptide as a prognostic marker of cardiac resynchronization therapy recipients.

Background: Although the dynamic changes of atrial natriuretic peptide (ANP) expressions in a failing heart are well-documented, the clinical implications of detailed measurements of each ANP molecular form processed from proANP remain unclear. Methods: Patients screening was conducted on patients who were eligible for cardiac resynchronization therapy (CRT) between 2014 and 2019 in our institution. Blood samples and echocardiographic parameters were collected on the day before and six months after implantation. Total ANP, proANP, and N-terminal fragment of proANP (NT-proANP) were examined as predictive biomarkers for cardiac death, left ventricular assist device implantation, and heart failure hospitalization following CRT implantation. Results: A total of 86 subjects (mean age 70 years, 64 males) who underwent successful CRT implantation were enrolled. Plasma levels of total ANP, proANP, and NT-proANP were not normally distributed [25.8 pM (interquartile range: 11.1-53.1), 2.2 pM (1.0-5.4), and 4.1 nM (2.4-7.1), respectively]. Over a median follow-up of 2.7 years, 31 patients (2 deaths and 29 heart failure hospitalizations) reached the endpoints. Among the different ANP forms, only NT-proANP emerged as an independent predictor of the composite outcome (adjusted odds ratio of 2.542 in those with levels above vs. below the median, 95 % confidence interval 1.151-5.615, p = 0.021). NT-proANP levels were associated with left atrial volume and left diastolic functional parameters and decreased in response to echocardiographic improvements at six months post-implantation (16 ± 44 % decrease in responders vs 18 ± 60 % increase in non-responders, p = 0.005). Conclusion: Pre-implantation NT-proANP levels could serve as a predictive factor for clinical outcomes in recipients of CRT.

Interference of cardiac implantable electronic devices and computed tomography imaging in the current era with a phantom model.

Introduction: Cardiac implantable electronic devices are used in patients with cardiac rhythm disorders. Computed tomography irradiation is not prohibited for patients with cardiac implantable electronic devices, despite adverse events being reported. Hence, appropriate preparation and knowledge are required before computed tomography irradiation can be carried out in these patients. Since there is limited knowledge or literature about the influence of computed tomography irradiation in cases with recent cardiac implantable electronic devices, we aimed to evaluate the adverse events and elucidate the necessary and sufficient safety measures associated with this therapy. Methods and Results: We placed cardiac implantable electronic devices on an anthropomorphic phantom model and observed their electrical activity in electrograms, while various protocols of computed tomography irradiation were implemented and adverse events evaluated. Oversensing with pauses of up to 3.2 s was observed in standard computed tomography protocols, but ventricular tachyarrhythmia or other clinically significant events could not be confirmed. Oversensing with pauses of up to 8.0 s was observed and ventricular tachyarrhythmia was detected in the maximum-dose protocols. However, treatments such as antitachycardia pacing or shock therapy for ventricular tachyarrhythmia were not observed because of their absence. Conclusion: Computed tomography irradiation for patients using cardiac implantable electronic devices is highly unlikely to cause clinically significant adverse events with the device settings and computed tomography protocols currently being used. Changing or monitoring the device settings routinely before computed tomography irradiation is not necessarily required for most patients.

Dynamics of unipolar J-ST elevation coupled to bipolar delayed potentials on the epicardium in Brugada syndrome: a case report.

Background: The area of abnormal bipolar potentials in the right ventricular epicardium is recognized as an arrhythmogenic substrate in patients with Brugada syndrome (BrS); however, the correlation between local potentials and Brugada-type surface electrocardiograms (ECGs) remains unclear. Case summary: A 49-year-old man with BrS who was hospitalized for refractory ventricular fibrillation underwent an electrocardiographic study with unipolar electrodes with the same bandwidth as surface ECGs. The right ventricular outflow tract epicardium showed abnormal bipolar potentials composed of split sharp and delayed dull components with coved-type J-ST elevation in the unipolar electrodes. The additional stimuli from the atrium gradually decreased the number of unipolar electrodes showing coved-type J-ST elevation along with a shortening of the local bipolar activation time. The pilsicainide provocation test induced a change in unipolar morphology from coved type to convex type and an intermittent local block of the divided and sharp components in bipolar electrodes. Of note, the unipolar J-ST elevation was not changed along with the localized conduction block in bipolar leads. Discussion: The unipolar electrode waveforms during sinus rhythm change together with bipolar electrodes, consisting of sharp and blunt components in BrS. However, the convex-type J-ST elevation in unipolar leads persisted irrespective of the local conduction block in bipolar leads after pilsicainide provocation. These findings suggest the complexity of BrS mechanisms.

Transvenous lead extraction versus surgical lead extraction or conservative treatment for cardiac implantable electronic device infections: Propensity score-weighted analyses of a nationwide claim-based database.

INTRODUCTION: Infection is one of the most important complications associated with cardiac implantable electronic device (CIED) therapy. The number of reports comparing the outcomes of transvenous lead extraction (TLE), surgical lead extraction, and conservative treatment for CIED infections using a real-world database is limited. This study investigated the association between the treatment strategies for CIED infections and their outcomes. METHODS: We performed a retrospective analysis of 3605 patients with CIED infections admitted to 681 hospitals using a nationwide claim-based database collected between April 2012 and March 2018. RESULTS: We divided the 3605 patients into TLE (n = 938 [26%]), surgical lead extraction (n = 182 [5.0%]), and conservative treatment (n = 2485 [69%]) groups. TLE was performed more frequently in younger patients and at larger hospitals (p for trend < .001 for both). The rate of TLE increased during the study period, whereas that of surgical lead extraction decreased (p for trend < .001 for both). TLE was associated with lower in-hospital mortality (vs. surgical lead extraction: odds ratio [OR], 0.20; 95% CI, 0.06-0.70; vs. conservative treatment: OR, 0.45; 95% CI: 0.22-0.94) and lower 30-day readmission rates (vs. surgical lead extraction: OR, 0.18; 95% CI: 0.06-0.56; vs. conservative treatment: OR, 0.06; 95% CI, 0.03-0.13) in propensity score-weighted analyses. CONCLUSIONS: Only 26% of patients hospitalized for CIED infections received TLE. TLE was associated with significantly lower in-hospital mortality and 30-day recurrence rates than surgical lead extraction and conservative treatment, suggesting that TLE should be more widely recommended as a first-line treatment for CIED infections.

Significance of effective cardiac resynchronization therapy pacing for clinical responses: An analysis based on the effective cardiac resynchronization therapy algorithm.

BACKGROUND: High percent ventricular pacing maximizes cardiac resynchronization therapy (CRT) response. An effective CRT algorithm classifies each left ventricular (LV) pace as effective or ineffective on the basis of the detection of QS or QS-r morphology on the electrogram; however, the relationship between percent effective CRT pacing (%e-CRT) and responses is unclear. OBJECTIVE: We aimed to clarify the association between %e-CRT and clinical outcomes. METHODS: Of the 136 consecutive CRT patients, 49 using the adaptive and effective CRT algorithm with percent ventricular pacing > 90% were evaluated. The primary and secondary outcomes were heart failure (HF) hospitalization and prevalence of CRT responders, defined as patients with an improvement in LV ejection fraction of ≥10% or a reduction in LV end-systolic volume of ≥15% after CRT device implantation, respectively. RESULTS: We divided the patients into the effective group (n = 25) and the less effective group (n = 24) by the median value of %e-CRT (97.4% [93.7%-98.3%]). During the median follow-up period of 507 days (interquartile range 335-730 days), the effective group had a significantly lower risk of HF hospitalization than the less effective group as revealed by Kaplan-Meier analysis (log-rank, P = .016). Univariate analysis revealed %e-CRT ≥ 97.4% (hazard ratio 0.12; 95% confidence interval 0.01-0.95; P = .045) as a predictor of HF hospitalization. The effective group had a higher prevalence of CRT responders than the less effective group (23 [92%] vs 9 [38%]; P < .001). Univariate analysis revealed that %e-CRT ≥ 97.4% (odds ratio 19.20; 95% confidence interval 3.63-101.00; P < .001) was a predictor of CRT response. CONCLUSION: High %e-CRT is associated with high CRT responder prevalence and low HF hospitalization risk.

OPTIMAL PLASMA CONCENTRATION OF THROMBOMODULIN ALFA TO TREAT SEPSIS-INDUCED DISSEMINATED INTRAVASCULAR COAGULATION.

ABSTRACT: Thrombomodulin alfa (TM alfa) has been shown effective for treatment of disseminated intravascular coagulation (DIC) associated with sepsis, although the optimal therapeutic plasma concentration has not been clarified. In the present study, the plasma trough concentration of TM alfa in septic patients with DIC was determined, then the cutoff value for that concentration showing influence on treatment outcome was calculated using a receiver operating characteristic curve. With a cutoff value of 1,010, the area under the curve of the receiver operating characteristic was 0.669 (95% confidence interval, 0.530-0.808), with sensitivity of 0.458 and specificity of 0.882. To evaluate its accuracy, patients were divided into those above or below the cutoff value, and 90-day survival rates were compared. The above-cutoff group showed a significantly higher 90-day survival rate (91.7%) as compared with the below-cutoff group (63.4%) ( P = 0.017), with a hazard ratio of 0.199 (95% confidence interval, 0.045-0.871). Interestingly, the incidence of hemorrhagic adverse effects was not significantly different between the groups. Based on these results, the recommended plasma trough concentration of TM alfa for treatment of septic DIC is 1,010 ng/mL, which should minimize the risk of severe bleeding while maximizing the therapeutic effect.

Clinical Predictors of Pacing Device Implantation in Implantable Cardiac Monitor Recipients for Unexplained Syncope.

Background: Implantable cardiac monitors (ICMs) help investigate the cause of unexplained syncope, but the probability and predictors of needing a pacing device thereafter remain unclear. Methods: We retrospectively analyzed the data of patients who received ICM insertion for unexplained syncope with suspected arrhythmic etiology. The data were obtained from a nationwide database obtained between April 1, 2012 and March 31, 2020. Multivariable mixed-effects survival analysis was performed to identify predictors of pacing device implantation (PDI), and a risk score model was developed accordingly. Results: In total, 2905 patients (age: 72 years [range: 60-78]) implanted with ICMs to investigate the cause of syncope were analyzed. During the median follow-up period of 128 days (range: 68-209) days, 473 patients (16%) underwent PDI. Older age, history of atrial fibrillation, bundle branch block (BBB), and diabetes were independent predictors of PDI in multivariable analysis. A risk score model was developed with scores ranging from 0 to 32 points. When patients with the lowest quartile score (0-13 points) were used as a reference, those with higher quartiles had a higher risk of PDI (second quartile: 14-15 points, hazard ratio [HR]: 3.86, 95% confidence interval [CI]: 2.62-5.68; third quartile: 16-18 points, HR: 4.67, 95% CI: 3.14-6.94; fourth quartile: 19-32 points, HR: 6.59, 95% CI: 4.47-9.71). Conclusions: The 4 identified predictors are easily assessed during the initial evaluation of patients with syncope. They may help identify patients with a higher risk of requiring permanent PDI.

Contexte: Les moniteurs cardiaques implantables (MCI) aident à déterminer la cause d'une syncope inexpliquée, mais la probabilité et les facteurs prédictifs du besoin d'un dispositif de stimulation cardiaque par la suite demeurent incertains. Méthodologie: Nous avons analysé de façon rétrospective les données de patients s'étant fait implanter un MCI après une syncope inexpliquée et chez lesquels une étiologie d'arythmie était soupçonnée. Les données proviennent d'une base de données nationale et s'étendent du 1er avril 2012 au 31 mars 2020. Une analyse de survie multivariable à effets mixtes a été effectuée pour cibler les facteurs prédictifs de l'implantation d'un dispositif de stimulation cardiaque (IDSC), et un modèle de score de risque a été conçu en conséquence. Résultats: Au total, les cas de 2905 patients (âge : 72 ans [écart interquartile (ÉI) : 60-78]) ayant reçu un MCI pour déterminer la cause de la syncope ont été analysés. Durant la période de suivi médiane de 128 jours (ÉI : 68-209), 473 patients (16 %) ont subi une IDSC. L'âge avancé, les antécédents de fibrillation auriculaire, le bloc de branche et le diabète étaient des facteurs prédictifs indépendants de l'IDSC dans l'analyse multivariable. Un modèle de score de risque a été conçu, les scores allant de 0 à 32 points. Lorsque les patients ayant un score dans le quartile inférieur (0 à 13 points) étaient utilisés à titre de référence, ceux ayant un score dans les quartiles supérieurs avaient un risque plus élevé d'IDSC (deuxième quartile : 14-15 points, rapport des risques instantanés [RRI] : 3,86, intervalle de confiance [IC] à 95 % de 2,62 à 5,68; troisième quartile : 16-18 points, RRI : 4,67, IC à 95 % de 3,14 à 6,94; quatrième quartile : 19-32 points, RRI : 6,59, IC à 95 % de 4,47 à 9,71). Conclusions: Les quatre facteurs prédictifs ciblés sont faciles à évaluer durant l'évaluation initiale des patients ayant subi une syncope. Ils peuvent aider à repérer les patients présentant un risque plus élevé d'avoir besoin d'un dispositif de stimulation cardiaque permanent.

Adding interactive face-to-face lectures to passive lectures effectively reduces radiation exposure during atrial fibrillation ablation.

BACKGROUND: Radiation exposure remains a major concern for electrophysiologists and patients. This study aimed to investigate the effect of altering awareness of radiation exposure during atrial fibrillation ablation using interactive face-to-face (FTF) lectures compared to passive lectures. METHODS: Patients who underwent their first catheter ablation with radiofrequency energy for atrial fibrillation between January 2014 and December 2020 were included in this study. All operators attended an e-learning lecture on radiation exposure before catheter ablation. The addition of FTF lectures to this lecture was introduced in 2018. The effect on radiation exposure was compared between the pre-FTF and FTF periods by comparing fluoroscopy time and radiation dose. RESULTS: A total of 896 patients [mean age, 66 ±â€¯11 years; 603 men (67 %)] were included in this study. For pre-FTF (n = 345), only pulmonary vein isolation (PVI) was performed in 112 patients and PVI with additional ablation in 233 patients. For FTF lectures (n = 551), PVI-only was performed in 302 patients and PVI with additional ablation in 249 patients. Fluoroscopy time, cumulative air kerma, and cumulative air kerma per time significantly reduced after FTF introduction in both PVI-only group [pre-FTF and FTF; 37 ±â€¯15 min and 16 ±â€¯10 min (p < 0.0001), 477 ±â€¯582 mGy and 108 ±â€¯156 mGy (p < 0.0001), 11 ±â€¯12 mGy/min, and 5 ±â€¯6 mGy/min (p < 0.0001), respectively] and PVI with additional ablation group [pre-FTF and FTF; 48 ±â€¯17 min and 15 ±â€¯13 min (p < 0.0001), 613 ±â€¯483 mGy and 68 ±â€¯96 mGy (p < 0.0001), 12 ±â€¯10 mGy/min, and 4 ±â€¯4 mGy/min (p < 0.0001), respectively]. There were no significant differences in intraoperative complications between the two periods. CONCLUSIONS: FTF lectures can reduce radiation exposure.

Differences in patient characteristics, clinical practice and outcomes of cardiac implantable electric device therapy between Japan and the USA: a cross-sectional study using data from nationally representative administrative databases.

OBJECTIVES: To identify differences in patient characteristics, clinical practice and outcomes of cardiac implantable electronic device (CIED) therapy between Japan and the USA. DESIGN: A cross-sectional study. SETTING: Nationally representative administrative databases from Japan and the USA containing hospitalisations with first-time implantations of pacemakers, implantable cardioverter-defibrillators (ICD) and cardiac-resynchronisation therapy with or without defibrillators (CRTP/CRTD). PARTICIPANTS: Patients hospitalised with first-time implantations of CIEDs. OUTCOME MEASURES: In-hospital mortality, in-hospital complication and 30-day readmission rates. RESULTS: Overall, 107 339 (median age 78 (71-84), 48 415 women) and 295 584 (age 76 (67-83), 127 349 women) records with CIED implantations were included from Japan and the USA, respectively. Proportion of women in defibrillator recipients was lower in Japan than in the USA (ICD, 21% vs 28%, p<0.001; CRTD, 24% vs 29%, p<0.001). Length of stay after CIED implantation was longer in Japan than in the USA for all device types (conventional pacemaker, 8(7-11) vs 1 (1-3) days, p<0.001; leadless pacemaker, 5 (3-9) vs 2 (1-5) days, p<0.001; ICD, 8 (7-11) vs 1 (1-3) days, p<0.001, CRTP, 9 (7-13) vs 2 (1-4) days, p<0.001; CRTD, 9 (8-14) vs 2 (1-4) days, p<0.001). In-hospital mortality after CIED implantation was similar between Japan and the USA ((OR) (95% CI), conventional pacemaker 0.58 (0.83 to 1.004); ICD 0.77 (0.57 to 1.03); CRTP 0.85 (0.51 to 1.44); CRTD 1.11 (0.81 to 1.51)), except that after leadless pacemaker implantation in Japan was lower than that in the USA (0.32 (0.23 to 0.43)). 30-day readmission rates were lower in Japan than in the USA for all device types (conventional pacemaker 0.55 (0.53 to 0.57); leadless pacemaker 0.50 (0.43 to 0.58); ICD 0.54 (0.49 to 0.58); CRTP 0.51 (0.42 to 0.62); CRTD 0.57 (0.51 to 0.64)). CONCLUSIONS: International variations in patient characteristics, practice and outcomes were observed. In-hospital mortality after CIED implantation was similar between Japan and the USA, except in cases of leadless pacemaker recipients.