Late life-threatening arrhythmia in patients with Brugada syndrome: Results from long-term follow-up in a large Japanese cohort.

INTRODUCTION: Most patients with Brugada syndrome (BrS) are first diagnosed in their 40s, with sudden cardiac death (SCD) often occurring in their 50s. Ventricular fibrillation (VF) may occur in some patients with BrS despite having been asymptomatic for a long period. This study aimed to assess the incidence and risk factors for late life-threatening arrhythmias in patients with BrS. METHODS: Patients with BrS (n = 523; mean age, 51 ± 13 years; male, n = 497) were enrolled. The risk of late life-threatening arrhythmia was investigated in 225 patients who had experienced no cardiac events (CEs: SCD or ventricular tachyarrhythmia) for at least 10 years after study enrollment. The incidence of CEs during the follow-up period was examined. RESULTS: During the follow-up of the 523 patients, 59 (11%) experienced CEs. The annual incidences of CEs were 2.87%, 0.77%, and 0.09% from study enrollment to 3, 3-10, and after 10 years, respectively. Among 225 patients who had experienced no CEs for at least 10 years after enrollment, four patients (1.8%) subsequently experienced CEs. Kaplan-Meier analysis revealed significant differences in the incidence of late CEs between patients with and without a history of symptoms (p = .032). The positive and negative predictive values of late CEs for the programmed electrical stimulation (PES) test were 2.9% and 100%, respectively. CONCLUSION: Our results suggest that patients with BrS who are asymptomatic and have no ventricular tachycardia/VF inducibility by PES are at extremely low risk of experiencing late life-threatening arrhythmias.

Electrogram characteristics at successful cryoablation sites in slow-fast atrioventricular nodal reentrant tachycardia.

PURPOSE: Cryoablation is a safe alternative to radiofrequency (RF) ablation for slow-fast atrioventricular reentrant tachycardia (AVNRT); however, optimal electrogram parameters for site selection remain unknown. We retrospectively investigated local electrograms for slow pathway (SP) modification in cryoablation. METHODS: Forty-five consecutive patients with slow-fast AVNRT who underwent cryoablation using a 6-mm-tip catheter were enrolled. Electrogram parameters for sites of successful SP modification (success-sites) were investigated; these included the interval between atrial activation at His and the last deflection of SP potential, defined as the His(A)-SPP interval. In 8 patients, 3-dimensional mapping by multi-electrode catheter was performed pre-ablation for more detailed SP assessment. RESULTS: Twenty-seven of 45 patients had successful SP modification by 1 cycle of freeze-thaw-freeze cryoablation at a single site with a low amplitude and fragmented SP potential. Among a total of 76 cryoablation sites in all patients, the His(A)-SPP interval at success-sites (45 sites) was significantly longer than that at unsuccess-sites (31 sites) (86 ± 9 vs.78 ± 10 msec, p < 0.0001). The AV amplitude ratio was not significantly different between success-and unsuccess-sites (0.21 ± 0.22 vs.0.25 ± 0.23, p = 0.429). The cutoff value of the His(A)-SPP interval for successful cryoablation was 82 msec with a sensitivity of 0.67 and specificity of 0.71 (AUC: 0.739; 95%CI: 0.626-0.852; p < 0.0001). Three-dimensional mapping in all 8 patients showed that sites with the most delayed atrial activation and the last deflection of the fragmented SP potential within the Koch's triangle coincided with success-sites. CONCLUSION: A longer His(A)-SPP interval and fractionated SP potential were characteristics of successful cryoablation for SP modification in slow-fast AVNRT.

Leiomyosarcoma arising from the ovarian vein as a gynecologic malignancy: Two case reports and a review of the literature.

Leiomyosarcoma arising from the ovarian vein has rarely been reported. Herein, we report two cases from a single institute. Given their direct connections to ovarian vessels, both leiomyosarcomas were initially suspected to be gynecological malignancies. In one case, leiomyosarcoma was discovered incidentally without any clinical symptoms; it had a close connection with the ovarian vein, was removed surgically, and the patient has survived for over 12 years. In another case, bowel obstruction caused by the tumor helped to identify metastatic leiomyosarcoma. Blood flow was supplied by the ovarian artery and grew into the lumen of the ovarian vein without invading adjacent organs. After surgical resection, the patient underwent 18 months of chemotherapy prior to palliative care. We propose that leiomyosarcoma arising from the ovarian vein should be treated as a gynecologic malignancy, especially if it develops in the lower abdomen.

Risk stratification in asymptomatic patients with Brugada syndrome: Utility of multiple risk factor combination rather than programmed electrical stimulation.

BACKGROUND: The prognostic value of programmed electrical stimulation (PES) in Brugada syndrome (BrS) remains controversial. Asymptomatic BrS patients generally have a better prognosis than those with symptoms. The purpose of this study was to evaluate the value of nonaggressive PES with up to two extra stimuli and predict clinical factors for risk stratification in asymptomatic BrS patients. METHODS: The study enrolled 193 consecutive asymptomatic BrS patients with type 1 ECG (mean age: 50 ± 13 years, 180 males) who underwent PES using a nonaggressive uniform protocol. Cardiac events (CEs: sudden cardiac death or ventricular tachyarrhythmia) during the follow-up period were examined. RESULTS: During a mean follow-up of 101 ± 48 months, seven asymptomatic patients (3.6%) had a CE. The incidence of CEs was not different between patients with and without inducible ventricular tachyarrhythmia by PES (p = .51). The clinical significance of risk factor combinations, including spontaneous type 1 ECG, family history of sudden cardiac death, QRS duration in lead V2 , and presence of J wave, was evaluated. Using the Kaplan-Meier method according to the number of risk factors, the prevalence of CE in patients with three or four risk factors was determined to be significantly higher than in those with one risk factor (p = .02 and p = .004, respectively). CONCLUSIONS: The present study suggests that inducibility of ventricular tachyarrhythmia does not predict future CEs in asymptomatic BrS patients. Combination analysis of the other four clinical risk parameters may be effective for risk assessment.

Long-term prognosis in patients with non-type 1 Brugada electrocardiogram: Results from a large Japanese cohort of idiopathic ventricular fibrillation.

BACKGROUND: Brugada syndrome (BrS) is diagnosed in patients with ST-segment elevation with spontaneous, drug-induced, or fever-induced type 1 morphology. Prognosis in type 2 or 3 Brugada electrocardiogram (Br-ECG) patients remains unknown. The purpose of this study is to evaluate long-term prognosis in non-type 1 Br-ECG patients in a large Japanese cohort of idiopathic ventricular fibrillation (The Japan Idiopathic Ventricular Fibrillation Study [J-IVFS]). METHODS: From 567 patients with Br-ECG in J-IVFS, a total of 28 consecutive non-type 1 patients who underwent programmed electrical stimulation (PES) (median age: 58 years, all male, previous sustained ventricular tachyarrhythmias [VTs] 1, syncope 11, asymptomatic 16) were enrolled. Cardiac events (CEs: sudden cardiac death or sustained VT/ventricular fibrillation) during the follow-up period were examined. RESULTS: During a median follow-up of 136 months, four patients (14%) had CEs. None of patients with PES- have experienced CEs. There was no statistically significant clinical risk factor for the development of CEs. Using the Kaplan-Meier method, the event-free rate significantly decreased in a group with all 3 risk factors (symptom, wide QRS complex in lead V2 , and positive PES) (p = .01). CONCLUSIONS: Our study revealed long-term prognosis in patients with non-type 1 Br-ECG. The combination analysis of these risk factors may be useful for the risk stratification of CEs in non-type 1 Br-ECG patients. The present study suggests that the patients with all these parameters showed high risk for CEs and need to be carefully followed.

Pulmonary Vein Isolation and Pacemaker Implantation in a Patient with Dextrocardia Situs Inversus.

A 70-year-old female with dextrocardia with situs inversus (DSI) totalis and inferior vena cava occlusion underwent radiofrequency catheter ablation because she had symptomatic paroxysmal atrial fibrillation (AF). Careful preoperative examination made successful pulmonary vein isolation through the left jugular vein approach. One-year later, however, AF recurred, and symptomatic sinus bradycardia or junctional bradycardia often occurred. Then, the pacemaker was implanted. We here reported a rare case of congenital abnormality, DSI with inferior vena cava occlusion who had undergone successful pulmonary vein isolation and pacemaker implantation without any complications.

Catheter Ablation of Refractory Ventricular Fibrillation Storm After Myocardial Infarction.

BACKGROUND: Ventricular fibrillation (VF) storm after myocardial infarction (MI) is a life-threatening condition that necessitates multiple defibrillations. Catheter ablation is a potentially effective treatment strategy for VF storm refractory to optimal medical treatment. However, its impact on patient survival has not been verified in a large population. METHODS: We conducted a multicenter, retrospective observational study involving consecutive patients who underwent catheter ablation of post-MI refractory VF storm without preceding monomorphic ventricular tachycardia. The target of ablation was the Purkinje-related ventricular extrasystoles triggering VF. The primary outcome was in-hospital and long-term mortalities. Univariate logistic regression and Cox proportional-hazards analysis were used to evaluate clinical characteristics associated with in-hospital and long-term mortalities, respectively. RESULTS: One hundred ten patients were enrolled (age, 65±11years; 92 men; left ventricular ejection fraction, 31±10%). VF storm occurred at the acute phase of MI (4.5±2.5 days after the onset of MI during the index hospitalization for MI) in 43 patients (39%), the subacute phase (>1 week) in 48 (44%), and the remote phase (>6 months) in 19 (17%). The focal triggers were found to originate from the scar border zone in 88 patients (80%). During in-hospital stay after ablation, VF storm subsided in 92 patients (84%). Overall, 30 (27%) in-hospital deaths occurred. The duration from the VF occurrence to the ablation procedure was associated with in-hospital mortality (odds ratio for each 1-day increase, 1.11 [95% CI, 1.03-1.20]; P=0.008). During follow-up after discharge from hospital, only 1 patient developed recurrent VF storm. However, 29 patients (36%) died, with a median survival time of 2.2 years (interquartile range, 1.2-5.5 years). Long-term mortality was associated with left ventricular ejection fraction <30% (hazard ratio, 2.54 [95% CI, 1.21-5.32]; P=0.014), New York Heart Association class ≥III (hazard ratio, 2.68 [95% CI, 1.16-6.19]; P=0.021), a history of atrial fibrillation (hazard ratio, 3.89 [95% CI, 1.42-10.67]; P=0.008), and chronic kidney disease (hazard ratio, 2.74 [95% CI, 1.15-6.49]; P=0.023). CONCLUSIONS: In patients with MI presenting with focally triggered VF storm, catheter ablation of culprit triggers is lifesaving and appears to be associated with short- and long-term freedom from recurrent VF storm. Mortality over the long-term follow-up is associated with the severity of underlying cardiovascular disease and comorbidities in this specific patient population.

Mobile mural thrombus and spontaneous echo contrast in ascending aorta after postoperative adjuvant cisplatin-based chemotherapy.

A 70-year-old asymptomatic male who had undergone a right nephrectomy for renal pelvic cancer was referred to us with a thrombus in the ascending aorta detected by contrast-enhanced computed tomography after chemotherapy with gemcitabine/cisplatin. Transesophageal echocardiography revealed a 4-cm mobile mural thrombus in the ascending aorta. An emergency thoracotomy for planned aortic root replacement was performed, but the intraoperative epi-aortic ultrasound indicated that the thrombus had disappeared, and it showed prominent spontaneous-echo contrast (SEC) in the ascending aorta. We speculate that vascular endothelium damage due to the cisplatin-based chemotherapy induced the thrombus and SEC in the ascending aorta.

A case of successful radiofrequency catheter ablation of ventricular tachycardia from the noncoronary cusp.

Idiopathic ventricular tachycardias (VTs) originating from the non-coronary cusp (NCC) are very rare. The previous reports suggested NCC-VTs were characterized by a narrower QRS duration and smaller III/II ratio than VTs originating from other coronary-cusps. We present a rare case of an NCC-VT with a local fragmented potential recorded at the NCC inconsistent with the known ECG characteristics of NCC-VTs.

Temporally stable frequency mapping using continuous wavelet transform analysis in patients with persistent atrial fibrillation.

INTRODUCTION: Dominant frequency (DF) derived from fast Fourier transform (FFT) analysis has failed to guide atrial fibrillation (AF) ablation since it cannot guarantee temporal stability. Continuous wavelet transform (CWT) analysis is another frequency analysis that can show the temporal stability of a frequency. METHODS AND RESULTS: Forty-four consecutive patients with persistent AF (PeAF) underwent pulmonary vein (PV) isolation (PVI) as the first-time catheter ablation. The PVs and left atrium were mapped and electrograms (EGMs) were recorded for 30 seconds at each site. Pseudo-frequency (PF) and coefficient of variation (CV) were calculated by CWT analysis. A PF with CV ≤ 10 was defined as a temporally stable PF (sPF). DF was also calculated by traditional FFT analysis from the first 5 seconds of the recorded EGMs. The highest sPF was shown inside the PVs in 20 patients (PV group), and at the non-PV sites in 24 patients (non-PV group). During the follow-up period of 15.3 ± 4.4 months, the ablation success rate in the PV group was significantly higher than that in the non-PV group (90% vs. 62%, P = 0.023). The location of the highest DF did not have a significant effect on ablation success rate between inside the PVs and at the non-PV sites. CONCLUSION: PVI results for PeAF were significantly worse for patients with highest sPF at the non-PV sites compared to patients with highest sPF sites inside the PVs. CWT analysis during AF could be used to verify whether PVI alone is sufficient for the first-time catheter ablation in patients with PeAF.

The prognostic impact of single extra-stimulus on programmed ventricular stimulation in Brugada patients without previous cardiac arrest: multi-centre study in Japan.

Aims: The prognostic value of programmed electrical stimulation (PES) in Brugada syndrome (BrS) remains controversial. One of the reasons for discrepant results may be due to the selection of stimulation protocol. We evaluated the prognostic value of a positive PES result (PES+) according to the inducible pacing sites and the number of extra-stimuli in BrS patients without previous cardiac arrest (CA). Methods and results: We enrolled 224 consecutive BrS patients without previous CA (mean age 51 ± 14 years, 209 males), who underwent PES with the identical protocol. Clinical outcomes of development of CA were explored in the patients with and without PES+ according to sites and number of extra-stimuli. During a mean follow-up period of 76 months, 12 cardiac events (CE: sudden cardiac death or documented VF) occurred (8 with and 4 without PES+). The incidence of CE was not different in patients with and without PES+, those with PES+ from RVA (n = 72) or RVOT (n = 60), and those with and without PES+ by up to 2 extra-stimuli (n = 58). However, in patients that were PES+ by a single extra-stimulus (n = 8) the incidence of CE was significantly higher than in those without PES+ (8.8 vs. 0.6%/year, P < 0.0001). On univariate analysis, syncope, spontaneous type 1 ECG, and PES+ by a single extra-stimulus were associated with CE. Conclusion: Details of the stimulation protocol may be important for risk assessment in BrS patients without previous CA. A single extra-stimulus may be useful in stratifying risk in patients with spontaneous type 1 ECG and syncope.

A larger vectorcardiographic QRS area is associated with left bundle branch block and good prognosis in patients with cardiac resynchronization therapy.

BACKGROUND: The association between the vectorcardiographic QRS area, bundle branch pattern and clinical long-term prognosis in patients who have undergone cardiac resynchronization therapy (CRT) has been unclear. METHODS: We enrolled 50 consecutive patients who underwent CRT. Vectorcardiograms were constructed from preprocedural digital 12-lead electrocardiograms using the inverse Dower method. The vectorcardiographic QRS area was defined as the root of the sum of the square in the integral between the ventricular deflection curve and the baseline from QRS beginning to end in leads X, Y, and Z. The primary endpoints were total mortality and admission due to heart failure. RESULTS: The vectorcardiographic QRS area in left bundle branch block (N = 13), right bundle branch block (N = 13), interventricular conduction delay (N = 11) and pacemaker rhythm (N = 13) were 218 ±â€¯99, 97 ±â€¯44, 90 ±â€¯40, and 131 ±â€¯58 µVs, respectively (ANOVA p < 0.001). During the mean follow-up period of 28 (2-86) months, 13 primary endpoints occurred. We divided patients into two groups: a large QRS area group (QRS area ≥114 µVs, N = 25) and a small QRS area group (QRS area <114 µVs, N = 25) by the median. The large QRS area group had a significantly lower rate of the primary endpoint compared with that of the small QRS area group (log rank 4.35, p = 0.037). The Cox regression analysis revealed that a QRS area <114 µVs was a significant predictor of the primary endpoint (HR 3.98, 95% CI 1.01-15.63, p = 0.048). CONCLUSIONS: A larger preprocedural vectorcardiographic QRS area was associated with left bundle branch block and good prognosis in patients who underwent CRT.

Left ventricular obstruction caused by a large hiatal hernia.

A 76-year-old man was admitted to our emergency department owing to chest pain, which started immediately after lunch. Although electrocardiogram revealed ST-segment elevation with hyperacute T-wave changes in the anterior lead tracings, emergency coronary angiography revealed normal coronary arteries. Echocardiography revealed left ventricular (LV) compression with left ventricular obstruction (LVO) caused by an echogenic mass. Computed tomography clearly revealed compression of both left atrial (LA) and LV by a large hiatal hernia. A large hiatal hernia can induce cardiac symptoms resulting from cardiac compression. This case highlights a possible association between chest pain and LVO caused by a hiatal hernia.

High Atrial Defibrillation Threshold With Internal Cardioversion Indicates Arrhythmogenicity of Superior Vena Cava in Non-Long-Standing Persistent Atrial Fibrillation.

BACKGROUND: The purpose of this study was to clarify the relation between atrial defibrillation threshold (ADFT) for internal cardioversion (IC) and arrhythmogenicity of the superior vena cava (SVC). METHODS AND RESULTS: A total of 159 consecutive patients (139 male, age 59.9±10.3 years) who underwent radiofrequency catheter ablation of atrial fibrillation (AF) were assessed. IC was performed in 50 patients with non-long-standing persistent AF (non-LSAF) with a purpose-built cardioversion catheter in which direct current is delivered between the right atrium and the coronary sinus. SVC arrhythmogenicity was defined as SVC firing initiating AF, SVC associated with maintenance of AF, or frequent ectopy in the SVC. In all 50 non-LSAF patients, AF termination was obtained on IC during the procedure except in 1 patient with SVC AF. In the patients with ADFT >10 J (n=10), SVC arrhythmogenicity was observed more often than in those with ADFT ≤10 J (n=40; 60% vs. 13%; P=0.004). There were no significant differences between the 2 groups in left atrial diameter (40.8±7.6 vs. 40.6±6.3 mm; P=0.92), persistent AF (33% vs. 50%; P=0.46), or other clinical parameters. The patients who underwent SVC isolation, however, had higher ADFT before SVC isolation than those who did not (15.5±8.8 vs. 9.2±4.4 J; P=0.01). CONCLUSIONS: High IC ADFT is associated with SVC arrhythmogenicity in non-LSAF patients.

Association of intramural fat deposition in the interatrial septum with focal atrial tachyarrhythmias originating near the atrioventricular node.

We describe a case with three focal atrial tachycardias (ATs) and focal atrial fibrillation (AF) originating from the interatrial septum (IAS) near the atrioventricular node (AVN). Contrast-enhanced computed tomography demonstrated the association of fat deposition within the anterior IAS near the AVN with successful ablation sites of these ATs and AF. This is the first report that the intramural fat deposition in the IAS could be associated with the formation of AT and AF re-entry circuits originating near the AVN.

Effects of ingesting highly branched cyclic dextrin during endurance exercise on rating of perceived exertion and blood components associated with energy metabolism.

We compared the effect of relatively low doses (15 g) of highly branched cyclic dextrin (HBCD) with that of maltodextrin during endurance exercise on the rating of perceived exertion (RPE) in a crossover, double-blind study of healthy volunteers. The RPE increased during exercise and its increase was significantly less at 30 and 60 min after ingesting HBCD than maltodextrin.

Validation of novel risk prediction models in patients with Brugada syndrome: A multicenter study in Japan.

BACKGROUND: Risk stratification in patients with Brugada syndrome (BrS) is challenging, especially in those at intermediate risk. The Predicting Arrhythmic evenT (PAT) score has recently been demonstrated to be excellent for predicting future arrhythmic events in patients without prior ventricular fibrillation (VF). However, validation studies are lacking. OBJECTIVE: This study aimed to assess the performance of a novel risk stratification model in predicting future VF events in patients with BrS in a Japanese multicenter cohort. METHODS: The PAT score was calculated for 413 patients with BrS (mean age, 50.9 ± 13.6 years; 395 men) from 59 hospitals in Japan, including 314 patients without prior VF. The incidence of developing VF during the follow-up period was investigated. RESULTS: During the 106.8-month follow-up period, 54 patients (13.1%) experienced VF events. Of the 314 patients without prior VF at enrollment, 14 (4.5%) experienced VF events. The incidence of VF events during the follow-up period was significantly higher in patients with PAT scores ≥ 10 than in those with scores < 10 (41/173 [23.7%] vs 13/240 [5.4%]; P < .0001) in the total cohort. No difference was observed in the incidence of VF events between patients with PAT scores ≥ 10 and < 10 among the 314 patients without prior VF (6/86 [7.0%] vs 8/228 [3.5%]; P = .22). PAT scores ≥ 10 predicted future VF events with a sensitivity and specificity of 42.9% and 73.3%, respectively. CONCLUSION: This Japanese multicenter registry demonstrated that the novel risk stratification model could not accurately predict future VF events in patients with BrS but without prior VF.

New clinical and electrocardiographic classification in patients with idiopathic ventricular fibrillation.

INTRODUCTION: The presence of early repolarization (ER) recently has been considered as a prognostic marker for sudden cardiac death in patients with idiopathic ventricular fibrillation (IVF), but there are certain numbers of IVF patients lacking ER. We aimed to clarify the clinical and electrocardiographic characteristics of the patients with IVF in the presence and absence of ER. METHODS AND RESULTS: We studied 64 consecutive IVF patients from the Japan Idiopathic Ventricular Fibrillation Study (J-IVFS) registry, which subjected with at least one episode of documented VF in the absence of structural heart diseases and excluding Brugada syndrome. We assessed clinical and electrophysiological characteristics in the IVF patients with and without ER. ER was defined as J-point elevation of >0.1 mV in either inferior or lateral leads. Twelve-lead electrocardiogram (ECG) demonstrated 24 (38%) of 64 patients with ER (ER[+] group) and the remaining 40 (62%) patients without ER (ER[-] group ). ER[+] group had a male predominance (92% for males) and ER[-] group revealed nearly equal distribution in both sexes. While no patients in ER[+] group showed intraventricular conduction disturbance (CD) with abnormal axis deviation and/or bundle branch block in ECG, 9 in ER[-] group had signs of CD (ER[-]/CD[+] subgroup). ER[-]/CD[+] subgroup had prolonged P-R interval and QRS duration compared to other patient groups. CONCLUSION: We found 3 distinct ECG patterns in IVF patients. In addition to the presence and absence of ER, there is a subgroup without ER demonstrating intraventricular CD, which represents a distinct clinical entity of IVF.