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.

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.

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.

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.

Persistent tachycardia within isolated pulmonary veins during atrial fibrillation ablation.

During circumferential pulmonary vein (PV) isolation for ongoing atrial fibrillation (AF), distinguishing passive conduction to the pulmonary vein (PV) from rapid PV arrhythmia in the isolated PV is difficult. Hence, the purpose of this study is to investigate both the feasibility of distinguishing the PV tachycardia after circumferential PV isolation and the electrophysiological characteristics of these tachycardia. Among 178 consecutive patients who underwent circumferential PV isolation during ongoing AF, fibrillatory PV converted to a regular cycle length PV tachycardia independent of the atrial rhythm (=independent PV tachycardia) in 13 PVs among 12 (7%) patients. We classified independent PV tachycardia according to 3 different atrial rhythms: sinus rhythm (type 1, n = 2), atrial tachycardia (type 2, n = 4), and AF (type 3, n = 6). independent PV tachycardia was observed in 3 right PV and 10 left PV (P = 0.0864). There were 10 mappable independent PV tachycardia, in which 8 were focal and 2 were macroreentrant tachycardia. i-PVT can be diagnosed in a small number of patients who underwent circumferential PV isolation during AF. The main mechanism or independent PV tachycardia was focal tachycardia mainly in the left PV.

Long-term prognosis in patients with Brugada syndrome based on Class II indication for implantable cardioverter-defibrillator in the HRS/EHRA/APHRS Expert Consensus Statement: multicenter study in Japan.

BACKGROUND: The HRS/EHRA/APHRS Expert Consensus Statement for implantable cardioverter-defibrillator (ICD) in Brugada syndrome (BrS) has recently been published. However, the validity of the Class II indication for ICD in BrS patients is still unknown. OBJECTIVE: The purpose of this study was to evaluate the validity of the Class II indication for ICD implantation in the Consensus Statement with a large Japanese cohort of BrS. METHODS: Among 410 patients with BrS, a total of 213 consecutive BrS patients with the Class II indication for ICD implantation (mean age 53 ± 14 years, 199 men) were enrolled. Clinical outcomes were compared between patients with Class IIa (n = 66) and those with Class IIb (n = 147) indication according to the Consensus Statement. RESULTS: The incidence of cardiac events (documented ventricular tachyarrhythmias or sudden cardiac death) during follow-up of 62 ± 34 months was significantly higher in patients with Class IIa (n = 8, 2.2% per year) than those with Class IIb indication (n = 4, 0.5% per year; P = .01). CONCLUSION: We confirmed that Class IIa indication identified a group of patients with increased risk compared to Class IIb indication for ICD in the Consensus Statement of 2013. In patients with Class II indication, the combination of a history of syncope and spontaneous type 1 ECG may be an important factor in distinguishing intermediate- from low-risk patients with BrS in Japan.

Significance of non-type 1 anterior early repolarization in patients with inferolateral early repolarization syndrome.

OBJECTIVES: The aim of this study was to investigate the significance of non-type 1 anterior early repolarization (NT1-AER) combined with inferolateral early repolarization syndrome (ERS). BACKGROUND: Inferolateral ERS might be a heterogeneous entity, although it excludes type 1 Brugada syndrome (BS). METHODS: Of 84 patients with spontaneous ventricular fibrillation, 31 ERS patients were divided into 2 groups. The ERS(A)-group consisted of inferolateral ER and NT1-AER--that is, notching or slurring with J-wave ≥ 1 mm at the end of QRS to early ST segment in any of V1 to V3 leads, in which the ST-T segment did not change to a coved pattern in the standard and high costal (second and third) electrocardiographic recordings even after drug provocation tests (n = 12). The other, ERS(B)-group, showed only inferolateral ER (n = 19). Clinical characteristics and outcomes were compared between the ERS groups, 40 patients with type-1 BS (BS-group), and 13 patients with idiopathic ventricular fibrillation lacking J-wave (IVF-group). RESULTS: Ventricular fibrillation occurred during sleep or near sleep in 10 of 12 patients in ERS(A)-group and in 22 of 40 patients in BS-group but in 2 of 19 patients in ERS(B)-group and in 1 of 13 patients in IVF-group (ERS[A] vs. ERS[B], p < 0.0001). Ventricular fibrillation recurrence was significantly higher in ERS(A)-group (58%), particularly in patients with J waves in the high lateral lead, and BS-group (55%), compared with ERS(B)-group (11%) and IVF-group (15%) (ERS[A] vs. ERS[B], p = 0.012). CONCLUSIONS: Inferolateral ERS comprises heterogeneous ER subtypes with and without NT1-AER. Coexistence of NT1-AER was a key predictor of poor outcome in patients with ERS.

Prognosis and risk stratification of young adults with Brugada syndrome.

Prognosis and risk factors for patients age 35years or younger with Brugada syndrome (BrS) were prospectively explored in a sub-analysis of the Japan Idiopathic Ventricular Fibrillation Study (J-IVFS) registry. During the period from February 2002 to January 2011, 69 cases (mean age 30±6years, male=66) of the young (at or less than 35years old) BrS were enrolled in J-IVFS and the clinical course was followed for more than 1year. They were divided into 3 groups: documented ventricular fibrillation (VF) or aborted sudden cardiac death (SCD) (VF group, 12 cases), syncope without documentation of VF (Syncope group, 17 cases) and asymptomatic group (Asympt. group, 40 cases). During a mean follow-up period of 43±27months, cardiac events (VF and/or SCD) developed in 8 cases, with 5 of 12 cases in the VF (41.7%), 2 of 17 cases in the Syncope (11.8%) and 1 of 40 cases in the Asympt. group (2.5%). The VF group had a worse prognosis for cardiac events than the Syncope and Asympt. group. Multivariate analysis revealed symptoms as a risk factor for predicting cardiac events.

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.

Efficacy of additional radiofrequency applications for spontaneous dissociated pulmonary vein activity after pulmonary vein isolation in patients with paroxysmal atrial fibrillation.

BACKGROUND: The aim is to evaluate the efficacy of additional radiofrequency ablation (RFCA) for spontaneous dissociated pulmonary vein activity (DPV-spike) after PV isolation (PVI) in patients with paroxysmal atrial fibrillation (AF). METHODS: One hundred fifty-two consecutive patients with paroxysmal AF referred for RFCA were enrolled. When DPV-spike was documented after PVI, we randomly assigned these patients to receive additional RFCA for DPV-spike or only PVI. We divided them into 4 groups: 87 patients without DPV-spike after PVI (No-spike group), 31 without DPV-spike after additional RFCA (Successful group), 8 with remaining DPV-spike after additional RFCA (Unsuccessful group), and 26 with DPV-spike after only PVI (Spike group). AF recurrence was evaluated among the 4 groups. RESULTS: After PVI, DPV-spike was documented in 87 PVs (14%) from 65 patients. During 16 ± 9 months of follow-up, the incidence of the freedom from AF was significantly higher in the No-spike group than that in the Spike group and Unsuccessful group (P < 0.05), and tended to be higher in the Successful group than that in the Spike group and Unsuccessful group (P = 0.08 and 0.11, respectively). In a multivariate analysis, the remaining PV-spike after ablation was an independent predictor of AF recurrence (HR 2.44; CI 1.10-5.43, P < 0.05). No major complications including PV stenosis were observed during the follow-up. CONCLUSIONS: DPV-spike after PVI may be associated with higher electrical activity within the PVs and may be one of the risk factors for AF recurrence. Additional RFCA for DPV-spike was effective to reduce the AF recurrence after PVI.

Usefulness of scintigraphy to predict electrical storms in severe idiopathic dilated cardiomyopathy.

BACKGROUND: Although several predictors of an electrical storm (ES) are indicated in patients with idiopathic dilated cardiomyopathy (IDCM), whether the severity of the myocardial tissue damage (SMTD) evaluated by myocardial perfusion SPECT (MPS) has an association with an ES remains unclear. The purpose of this study was to elucidate the clinical significance of SMTD for the prediction of ES in IDCM patients with an ICD. METHODS: Thirty-seven (27 men, mean age 58 ± 15 years) IDCM patients receiving ICD implantations for secondary prevention with preoperative MPS were enrolled in this study. The medical history, physical and laboratory findings, electrocardiograms, echocardiograms and MPS findings were evaluated. The SMTD was assessed by the summed scores of 17 segments using a 4-point system (0, normal ~3, severe defect). RESULTS: During a mean follow-up of 43.9 ± 30.7 months, an ES developed in 12/37 (32.4 %) patients. The SMTD score predicted an ES with a 92 % sensitivity and 56 % specificity, at a cut-off score of 10. In addition, a multivariate analysis showed that the SMTD score remained an independent predictor of an ES (HR 1.09/score 1 increase, 95 % CI 1.01-1.19, p = 0.02). The SMTD score was significantly associated with three indices of late potentials on the signal-averaged electrocardiograms, and was significantly higher in patients with positive late potentials (p = 0.0006). CONCLUSION: SMTD score assessed by MPS has a strong correlation to the late potentials and higher SMTD score may increase the risk of ES among patients with IDCM and an ICD.

The prognostic value of early repolarization (J wave) and ST-segment morphology after J wave in Brugada syndrome: multicenter study in Japan.

BACKGROUND: The prognostic value of a J wave and ST-segment morphology after J wave in inferolateral leads in Brugada syndrome (BS) is still unknown. OBJECTIVE: To evaluate the prognostic value of a J wave and ST-segment morphology after J wave in a large Japanese cohort of BS. METHODS: A total of 460 consecutive patients with BS (mean age 52±14 years, 432 men) were enrolled. The presence and location of leads showing a J wave, ST-segment morphology after J wave, and clinical outcomes were evaluated in patients with documented ventricular fibrillation (VF) (N = 84), those with syncope without documented VF (N = 109), and subjects without symptoms (N = 267). RESULTS: The prevalence of a J wave in the inferior and/or lateral leads was 12% (53 cases). The prevalence of a J wave among the 3 groups was not different. The incidence of cardiac events (sudden cardiac death or VF) during a mean follow-up period of 50±32 months was not different in patients with (11%) or without (8%) a J wave. Patients with a J wave in both inferior and lateral leads or with horizontal ST-segment morphology after J wave showed a higher incidence of cardiac events than those without (P = .04 and .02, respectively). Multivariate analysis revealed symptoms, QRS duration in lead V2>90 ms, and inferolateral J wave and/or horizontal ST-segment morphology after J wave were important for predicting cardiac events. CONCLUSION: The presence of a J wave in multiple leads and horizontal ST-segment morphology after J wave may indicate a highly arrhythmogenic substrate in patients with BS.

Clinical impact of the number of extrastimuli in programmed electrical stimulation in patients with Brugada type 1 electrocardiogram.

BACKGROUND: Use of programmed electrical stimulation (PES) for risk stratification of Brugada syndrome (BrS) is controversial. OBJECTIVE: To elucidate the role of the number of extrastimuli during PES in patients with BrS. METHODS: Consecutive 108 patients with type 1 electrocardiogram (104 men, mean age 46 ± 12 years; 26 with ventricular fibrillation [VF], 40 with syncope, and 42 asymptomatic) underwent PES with a maximum of 3 extrastimuli from the right ventricular apex and the right ventricular outflow tract. Ventricular arrhythmia (VA) was defined as VF or nonsustained polymorphic ventricular tachycardia >15 beats. Patients with VA induced by a single extrastimulus or double extrastimuli were assigned to group SD (Single/Double), by triple extrastimuli to group T (Triple), and the remaining patients to group N. RESULTS: VA was induced in 81 patients (VF in 71 and polymorphic ventricular tachycardia in 10), in 4 by a single extrastimulus, in 41 by double extrastimuli, and in 36 by triple extrastimuli. During 79 ± 48 months of follow-up, 24 patients had VF events. Although the overall inducibility of VA was not associated with an increased risk of VF (log-rank P = .78), group SD had worse prognosis than did group T (P = .004). Kaplan-Meier analysis in patients without prior VF also showed that group SD had poorer outcome than did group T and group N (P = .001). Positive and negative predictive values of VA induction with up to 2 extrastimuli were, respectively, 36% and 87%, better than those with up to 3 (23% and 81%, respectively). CONCLUSIONS: The number of extrastimuli that induced VA served as a prognostic indicator for patients with Brugada type 1 electrocardiogram. Single extrastimulus or double extrastimuli were adequate for PES of patients with BrS.

Effect of sodium-channel blockade on early repolarization in inferior/lateral leads in patients with idiopathic ventricular fibrillation and Brugada syndrome.

BACKGROUND: A high incidence of early repolarization (ER) pattern in the inferolateral leads has been reported in patients with idiopathic ventricular fibrillation (IVF). Brugada syndrome (BS) is characterized by J-point or ST-segment elevation in the right precordial leads and ventricular fibrillation, and some patients with BS also have ER in the inferolateral leads. OBJECTIVE: To compare the clinical characteristics and effects of sodium-channel blockade on ER between IVF patients with ER (early repolarization syndrome [ERS]) and BS patients with or without ER. METHODS: Fourteen patients with ERS and 21 patients with BS were included in this study. ER was defined as an elevation of at least 0.1 mV from baseline in the QRS-T junction in the inferorolateral leads. Provocative tests with sodium-channel blockers were conducted in all patients with ERS to distinguish ERS from BS. RESULTS: In the ERS group, all patients were male and most patients experienced ventricular fibrillation during sleep or low activity (79%). ER was attenuated by sodium-channel blockers in most patients with ERS (13/14, 93%) and BS (5/5, 100%), whereas ST-segment elevation was augmented in the right precordial leads in the BS group. The rates of positive late potentials were significantly higher in the BS group (60%) than in the ERS group (7%) (P <.01). CONCLUSIONS: Some similarities were observed between ERS and BS, including gender, arrhythmia triggers, and response of ER to sodium-channel blockers. Unlike the ST segment in the right precordial leads in BS, ER was attenuated in patients with both ERS and BS, suggesting a differential mechanism between ER in the inferolateral leads and ST elevation in the right precordial leads.

Incessant monomorphic ventricular tachycardia induced by the proarrhythmic effect of amiodarone.

This case report describes incessant monomorphic ventricular tachycardia (VT), not torsade de pointes, induced by intravenous amiodarone in a 48-year-old woman with dilated cardiomyopathy. VT was reproducibly triggered by short coupled premature ventricular complex (PVC) with different morphology from VT. After amiodarone infusion, the coupling interval of initiating PVC was prolonged, and moreover, the morphology of initiating PVC became the same as that of VT. Though amiodarone has become the first line drug to treat ventricular tachyarrhythmias in patients with cardiac dysfunction, it is important to be aware of its proarrhythmic effect, which may lead to an electrical storm of monomorphic VT.

Effects of exercise training in patients with chronic heart failure and advanced left ventricular systolic dysfunction receiving ß-blockers.

BACKGROUND: It remains unclear whether patients with chronic heart failure (CHF) and advanced left ventricular (LV) dysfunction on ß-blocker therapy benefit from exercise training (ET). METHODS AND RESULTS: We studied 45 CHF patients with advanced LV dysfunction [ejection fraction (LVEF) < 25%] and impaired exercise tolerance [normalized peak oxygen uptake (PVO2) < 70%] receiving a ß-blocker: 33 patients participated in a cardiac rehabilitation program with ET (ET group) and 12 did not (inactive control group). Exercise capacity, LV dimension and plasma B-type natriuretic peptide (BNP) were assessed before and after a 3-month study period. At baseline, both groups had markedly reduced LVEF (ET group 18 ± 4% vs. Control group 18 ± 5%, NS) and impaired exercise capacity (normalized PVO2 51 ± 10% vs. 55 ± 9%, NS). Although one patient in the ET group withdrew from the program due to worsening CHF, no serious cardiac events occurred during the ET sessions. After 3 months, the ET group (n = 24) had significantly improved PVO2 by 16 ± 15% (1,005 ± 295 to 1,167 ± 397ml/min, P < 0.001), while the PVO2 of the control group was unchanged. LV end-diastolic dimension decreased in both groups to a similar extent, but plasma BNP was significantly decreased only in the ET group (432 to 214 pg/ml, P < 0.05). CONCLUSIONS: The data indicate that in CHF patients with advanced LV dysfunction on ß-blocker therapy, ET successfully improves exercise capacity and BNP without adversely affecting LV remodeling or causing serious cardiac complications.

Efficacy of out-patient cardiac rehabilitation in low prognostic risk patients after acute myocardial infarction in primary intervention era.

BACKGROUND: The efficacy of out-patient cardiac rehabilitation (OPCR) in patients with a low prognostic risk after acute myocardial infarction (AMI) is unclear in the recent primary intervention era. METHODS AND RESULTS: A total of 637 AMI patients who participated in in-hospital cardiac rehabilitation were divided into 2 groups; low prognostic risk group (n=219; age <65 years, successful reperfusion, Killip class I, peak serum creatine kinase <6,000U/L, and left ventricular ejection fraction ≥40%) and non-low prognostic risk group (n=418). The prevalence of coronary risk factors (CRF) was compared between the 2 groups. Then, in the low-risk group, the efficacy of OPCR was compared between active OPCR participants (n=52; ≥20 sessions/3 months) and non-active participants (n=60; <6 sessions/3 months). Compared with the non-low prognostic risk group, the low prognostic risk group had a significantly higher prevalence of current smokers (72% vs. 49%, P<0.05) and patients with multiple CRF (3 or more; 49% vs. 39%, P<0.05). Among the low- risk group, active OPCR participants showed a significantly greater improvement in exercise capacity (peak VO(2), P<0.05) and maintained a better CRF profile (total cholesterol, triglyceride and blood pressure, all P<0.05) than inactive participants at 3 months. CONCLUSIONS: Low prognostic risk AMI patients have a higher prevalence of multiple CRF than non-low risk patients. Even in this low risk group, active participation in OPCR is associated with improved exercise capacity and better CRF profile.

Augmented ST-segment elevation during recovery from exercise predicts cardiac events in patients with Brugada syndrome.

OBJECTIVES: The goal of this study was to evaluate the prevalence and the clinical significance of ST-segment elevation during recovery from exercise testing. BACKGROUND: During recovery from exercise testing, ST-segment elevation is reported in some patients with Brugada syndrome (BrS). METHODS: Treadmill exercise testing was conducted for 93 patients (91 men), 46 ± 14 years of age, with BrS (22 documented ventricular fibrillation, 35 syncope alone, and 36 asymptomatic); and for 102 healthy control subjects (97 men), 46 ± 17 years of age. Patients were routinely followed up. The clinical end point was defined as the occurrence of sudden cardiac death, ventricular fibrillation, or sustained ventricular tachyarrhythmia. RESULTS: Augmentation of ST-segment elevation ≥0.05 mV in V(1) to V(3) leads compared with baseline was observed at early recovery (1 to 4 min at recovery) in 34 BrS patients (37% [group 1]), but was not observed in the remaining 59 BrS patients (63% [group 2]) or in the 102 control subjects. During 76 ± 38 months of follow-up, ventricular fibrillation occurred more frequently in group 1 (15 of 34, 44%) than in group 2 (10 of 59, 17%; p = 0.004). Multivariate Cox regression analysis showed that in addition to previous episodes of ventricular fibrillation (p = 0.005), augmentation of ST-segment elevation at early recovery was a significant and independent predictor for cardiac events (p = 0.007), especially among patients with history of syncope alone (6 of 12 [50%] in group 1 vs. 3 of 23 [13%] in group 2) and among asymptomatic patients (3 of 15 [20%] in group 1 vs. 0 of 21 [0%] in group 2). CONCLUSIONS: Augmentation of ST-segment elevation during recovery from exercise testing was specific in patients with BrS, and can be a predictor of poor prognosis, especially for patients with syncope alone and for asymptomatic patients.

Clinical effect of implantable cardioverter defibrillator replacements: when should you resume driving after an implantable cardioverter defibrillator replacement?

BACKGROUND: The intervals of the driving restrictions after an implantable cardioverter defibrillator (ICD) replacement vary across the different countries around the world. However, little is known regarding the appropriate duration for driving restrictions after an ICD replacement. The aim of this study was to investigate the clinical effect of ICD replacements and to elucidate when to resume driving an automobile after an ICD replacement. METHODS AND RESULTS: The study reviewed 139 consecutive patients with an ICD replacement in order to evaluate the incidence of ICD therapies before and after ICD replacements, and to assess the time-dependence of the ICD therapies after the ICD replacement. There was no significant difference in the incidence of ICD therapies delivered during durations of 3 months and 6 months before and after the ICD replacement (P=0.28, and 1.0, respectively). ICD therapies after the replacements were observed in 8.6% of the patients who were legally eligible to drive according to the Japanese guidelines at 1 year, and that was associated with a relatively low annual risk of death or injury to others. CONCLUSIONS: Implantable cardioverter defibrillator replacements did not affect the future ICD therapies under similar algorithms. The appropriate interval for driving restrictions after an ICD replacement is recommended to be a week or so, with a system integrity check performed before resumption of driving.