The R Wave Amplitude in Lead aVL Could Predict Successful Catheter Ablation of Ventricular Arrhythmias Originating below the His Bundle Region of the Right Ventricle.

Radiofrequency catheter ablation (RFCA) to treat ventricular arrhythmias (VAs) originating below the His bundle (HB) region of the right ventricular (RV) septum could impair the atrioventricular node conduction. This study aimed to clarify the parameters of the 12-lead electrocardiography that predict successful RFCA of VAs originating from this region. This study included 20 consecutive patients (13 men; mean age, 68 ± 7 years) with monomorphic VAs in whom the earliest ventricular activation during the VA was below the HB region of the RV septum. According to the ablation results, the patients were divided into two groups: successful ablation (S-group; n = 10) and failed ablation groups (F-group; n = 10). The electrocardiographic parameters during the VAs and RFCA results were assessed. The R wave amplitudes in leads aVL (P = 0.001) and I (P = 0.010) in the S-group were both smaller than those in the F-group. In addition, the S-group had smaller negative deflection amplitudes in leads III (P = 0.002) and aVF (P = 0.003) than the F-group. According to the receiver operating characteristic curve analysis, the most useful electrocardiographic parameter for predicting successful ablation was the R wave amplitude in lead aVL (area under the curve, 0.895; P < 0.001); a cutoff value of < 1.3 mV predicted a successful RFCA with the highest accuracy (sensitivity, 90%; specificity, 80%; positive predictive value, 82%; negative predictive value, 89%). The R wave amplitude in lead aVL was the most useful parameter for predicting a successful RFCA to treat VAs originating below the HB region of the RV septum.

Catheter ablation of ventricular tachycardia in dilated-phase hypertrophic cardiomyopathy: Substrate characterization and ablation outcome.

INTRODUCTION: Catheter ablation is a therapeutic option to suppress ventricular tachycardia (VT) in the setting of dilated-phase hypertrophic cardiomyopathy (DHCM). However, the characteristics of the arrhythmogenic substrate and the ablation outcome are not fully illustrated. METHOD: A total of 23 ablation procedures for drug-refractory sustained monomorphic VTs in 13 DHCM patients (60 ± 11 years, one female, the left ventricular [LV] ejection fraction 39% ± 9%, the LV mass index 156 ± 39 g/m2 ) were performed. The distribution of VT substrate as endocardial or epicardial/intramural was based on detailed mapping and ablation response during VT. RESULT: Two patients underwent ablation of sustained monomorphic VT that was not scar-mediated tachycardia. Of the remaining 11 patients, eight (73%) patients had VT substrate in the basal regions, most frequently at the epicardial and/or intramural basal antero-septum. None of the patients had VT substrate located at the LV inferolateral region. Ablation at the right ventricular septum and the aortic cusps was done in four and five patients, respectively. Other approaches including bipolar and chemical ablations, were done in three and two patients, respectively. Six (55%) out of 11 patients (two patients lost follow-up) had VT recurrence. All the six patients had basal substrate. However, anti-tachycardia pacing was sufficient for VT termination except in one patient. CONCLUSION: Catheter ablation of VT in patients with DHCM is challenging because of the predominant basal anteroseptal epicardial/intramural location of arrhythmogenic substrate. An ablation approach from multiple sites and/or adjunctive interventional techniques are often required.

Preprocedural restoration of sinus rhythm and left atrial strain predict outcomes of catheter ablation for long-standing persistent atrial fibrillation.

INTRODUCTION: Catheter ablation (CA) for long-standing persistent atrial fibrillation (LS-AF) remains challenging. We aimed to explore whether sinus rhythm (SR) restoration and left atrium (LA) function after pretreatment with antiarrhythmic drugs (AAD's) and electrical cardioversion (ECV) predict procedural outcomes. METHODS AND RESULTS: We included 100 consecutive patients with LS-AF who were treated with AAD/ECV for at least 3 months before CA. The echocardiographic LA strain during reservoir phase (LASr) was assessed after pretreatment as a marker of LA fibrosis. The recurrence was recorded for ≥1 year after the last procedure. During a 34 ± 16-month follow-up period, the single and multiple procedures and pharmaceutically assisted success rates were 40% and 71%, respectively. Patients with preprocedural SR restoration and higher LASr showed a significantly higher recurrence-free probability after the last CA (logrank P = .001 and P < .001, respectively). Failure of preprocedural SR restoration and LASr ≤8.6% were independently associated with recurrence after the last CA (hazard ratio [HR]: 3.13, 95% confidence interval [CI]: 1.42-6.91, P = .005; HR: 3.89, 95% CI: 1.65-9.17, P = .002, respectively). These parameters added incrementally to the predictive value of AF duration and LA dilatation (P = .03 and P = .002, respectively) and improved the recurrence-risk stratification (net reclassification improvement = 0.39; 95% CI = 0.13-0.65; P = .003). CONCLUSION: In patients with LS-AF, the inability to restore SR and lower LASr after AAD/ECV treatment independently and incrementally predicts the recurrence after CA. These findings might be useful for determining LS-AF ablation candidates.

Prevention of periprocedural ischemic stroke and management of hemorrhagic complications in atrial fibrillation ablation under continuous warfarin administration.

INTRODUCTION: This study aimed to determine the effects of continuing warfarin administration during the periprocedural period of catheter ablation for atrial fibrillation (AF) on the prevention of stroke complications and to evaluate the management of hemorrhagic complications occurring with this approach. METHODS AND RESULTS: A total of 3,280 patients undergoing AF catheter ablation at our institution were divided into 2 groups: the first 1,953 patients who discontinued warfarin 3-4 days before AF ablation and were bridged with heparin (warfarin-discontinued group), and the last 1,327 patients who continued warfarin throughout the periprocedural period (warfarin-continued group). Symptomatic stroke or transient ischemic attack occurred in 13/1,953 patients (0.67%) in the warfarin-discontinued group and in 2/1,327 patients (0.15%) in the warfarin-continued group (P = 0.021). None of the patients with therapeutic international normalized ratio at the time of the procedure had periprocedural thromboembolism in the warfarin-continued group. Major hemorrhagic complications occurred in 26/1,953 patients in the warfarin-discontinued group (1.3%; 25 with cardiac tamponade and 1 with retroperitoneal bleeding), and in 15/1,327 patients in the warfarin-continued group (1.1%; 14 with cardiac tamponade and 1 with abdominal wall bleeding) (P = 0.80). Of the 14 warfarin-continued patients with cardiac tamponade, 13 were administered prothrombin complex concentrate (PCC) and vitamin K; the bleeding was stopped safely without surgical repair. CONCLUSION: The continuation of warfarin during the periprocedural period of AF ablation could reduce the incidence of stroke without increasing hemorrhagic complications. When cardiac tamponade occurred with this approach, it was safely treated with PCC and vitamin K.

Coronary venous lead implantation after an evaluation by virtual histology intravascular ultrasound and stenting of a stenosis.

We describe a patient who developed coronary vein (CV) stenosis shortly (<3 months) after an initial left ventricular (LV) lead implantation with significant fibrous tissue. The virtual histological intravascular ultrasound analysis was useful for characterizing the plaque component of the stenotic lesion and formulating the strategy. A summarized review of the CV angioplasty for LV lead implantations disclosed that CV stenosis was often found in patients who had a previous history of cardiac surgery or an LV lead implantation and that a stent implantation was required to deploy the LV lead in the targeted CV in some (9.3%) patients.

Initial multicenter clinical experience with the first-generation endoscopic guided laser balloon in Japan.

BACKGROUND: Isolation of the pulmonary veins (PVs) is the golden standard for atrial fibrillation (AF) ablation. To achieve a permanent PV isolation, the endoscopic guided HeartLight laser balloon system was invented. We analyzed the safety and efficacy of this laser balloon system. METHODS AND RESULTS: Three hundred four patients from 21 investigational sites inside Japan were enrolled in this study. One thousand sixty-two out of 1175 PVs (90.4%) were isolated using the HeartLight laser balloon. The isolation rate of the left superior, left inferior, right superior, and right inferior PVs was 87.8%, 91.3%, 91.6%, and 92.1%, respectively. The procedure time, defined as the time from the venous access to taking out the balloon, was 155 ± 39 min. The fluoroscopic time was 44 ± 25 min. The mean follow-up period was 309 ± 125 days. The freedom from AF recurrence at 3 months was 89.0% and at 12 months 82.1%. Adverse events occurred in 22 patients (7.2%) including phrenic nerve injury lasting more than 3 months in 1.6% and strokes in 1.0% of the patients. CONCLUSIONS: This initial experience demonstrated that the laser balloon ablation was feasible for PV isolation in Japanese AF patients.

Clinical characteristics of massive air embolism complicating left atrial ablation of atrial fibrillation: lessons from five cases.

AIMS: This study aimed to elucidate the clinical characteristics of massive air embolism occurring during atrial fibrillation (AF) ablation. METHODS AND RESULTS: Of 2976 patients undergoing AF ablation, 5 patients complicated by serious air embolism were examined. Atrial fibrillation ablation was performed with the use of three long sheaths for circular mapping and ablation catheters under conscious sedation. Two patients had air spontaneously introduced through a haemostasis valve of the long sheaths, at the end of long apnoea caused by the sedation, even though the catheters were placed within the long sheaths. The remaining three patients, all of whom also exhibited long apnoea, had air entry at the circular mapping catheter exchanges. Air accumulated in the right and left ventricles, left atrial appendage, right coronary artery, and ascending aorta. Haemodynamic collapse and hypoxaemia occurred in all and two patients, respectively, and supportive treatment and the accumulated air were aspirated. ST elevation, haemodynamic collapse, and hypoxaemia persisted for 10-35 min; however, all patients recovered completely. After we changed the sedative to one with less respiratory depressive effects and the timing of the saline flush at the circular mapping catheter exchanges, we never experienced such serious complications any further. CONCLUSION: Serious air embolism can occur in patients with long apnoea under sedation during AF ablation with the use of long sheaths. Supportive therapy and air aspiration were effective in resolving the complication. A sedative that causes less respiratory depression and the timing of the saline flush were important for preventing air embolism.

Tachycardia associated with twin atrioventricular nodes in an infant with heterotaxy and interruption of inferior vena cava.

We report a 12-month-old boy with heterotaxy and interruption of inferior vena cava who showed sustained tachycardia associated with twin atrioventricular nodes (AVNs). Atrioventricular reciprocating tachycardia with antegrade conduction through the posterior AVN and retrograde conduction through the anterior AVN were successfully ablated using an upper approach from the left internal jugular vein.

Surgical removal of infected pacemaker leads without cardiopulmonary bypass after failed extraction using the Excimer Laser Sheath Extraction System.

With the growing number of cardiac pacemakers and internal cardioverter defibrillator implantations, problems with endocardial lead infection have been increasing. The newly developed Excimer Laser Sheath Lead Extraction System has been recognized as being highly useful for removing chronic infected leads. However, serious bleeding complications are a concern when this system is used. Here we report our experience with a 67-year-old man who was diagnosed with pacemaker endocarditis. Initially, lead removal was attempted using the Excimer Laser Sheath Extraction System, though this was abandoned because of severe adhesion of the leads and the junction of the supra vena cava (SVC) with the right atrium. Surgical removal of the leads was performed without using cardiopulmonary bypass and the leads were removed without any complications. During surgery, we found there was a silent perforation of the innominate vein brought about by the Excimer Laser Sheath System. Also, the junction of the SVC with the right atrium was thought to be an area potentially at high risk of perforation, because of a lack of surrounding tissue. It is our opinion that those who carry out procedures with the Excimer Laser Sheath System should understand the potential risk of perforation based on cardiac anatomy and should be prepared for lethal bleeding complications. Also, for emergent situations, we believe that close backup by a cardiovascular surgical team should be considered essential for performing the Excimer Laser Sheath Lead Extraction safely.

Impact of adaptive cardiac resynchronization therapy in patients with systolic heart failure: Beyond QRS duration and morphology.

BACKGROUND: Mechanical and electrical restoration by cardiac resynchronization therapy (CRT) with adaptive pacing algorithm (aCRT) in heart failure patients with a moderately wide (120-149 ms) QRS has not been fully evaluated. The purpose of this study was to investigate the therapeutic effect of aCRT compared with conventional biventricular CRT (BiV-CRT) regardless of QRS morphology. METHODS: Seventeen consecutive patients with a QRS ≥120 ms, regardless of morphology, underwent CRT device implantation with an aCRT pacing algorithm. Propensity score matched analysis was performed to evaluate the impact of aCRT on the improvement in mechanical and electrical parameters after CRT device implantation using historical controls (HC) from the clinical registry of BiV-CRT (START trial). RESULTS: Left ventricular (LV) volume significantly decreased after CRT in all patients in both the aCRT and HC groups. The difference in relative reduction of LV end-systolic volume (LVESV) was not significantly different between the 2 arms. QRS shortening after CRT was significantly greater in the aCRT group than in the BiV-CRT group, and the difference was prominent in patients with a moderately wide QRS (120-149 ms). In patients with a moderately wide QRS, the relative reduction in LVESV [39 (29-47)% vs. 2 (-6-20)%, p = 0.04] and proportion of LV volume responders (90% vs. 38%, p = 0.04) were significantly greater in the aCRT group than in the HC group. The proportion of volume responders was not significantly different in patients with a wide QRS (≥150 ms). CONCLUSIONS: The aCRT algorithm improved electrical and mechanical parameters in patients with a moderately wide QRS, regardless of QRS morphology.

Primary results from the Japanese Heart Failure and Sudden Cardiac Death Prevention Trial (HINODE).

AIMS: The HINODE study aimed to analyse rates of mortality, appropriately treated ventricular arrhythmias (VA), and heart failure in Japanese patients and compared with those in Western patients. METHODS AND RESULTS: After treatment decisions following contemporary practice in Japan, patients were prospectively enrolled into four cohorts: (i) internal cardioverter-defibrillator (ICD), (ii) cardiac resynchronization therapy (CRT) defibrillator (CRT-D), (iii) standard medical therapy ('non-device': ND), or (iv) pacing (indicated for CRT; received pacemaker or CRT pacing). Cohorts 1-3 required a left ventricular ejection fraction ≤35%, a history of heart failure, and a need for primary prevention of sudden cardiac death based on two to five previously identified risk factors. Endpoint outcomes were adjudicated by the independent committees. ICD and CRT-D cohorts, considered as high-voltage (HV) cohorts, were pooled for Kaplan-Meier analysis and propensity-matched to Multicenter Automatic Defibrillator Implantation Trial-Reduce Inappropriate Therapy (MADIT-RIT) arm B and C patients. The study enrolled 354 patients followed for 19.6 ± 6.5 months, with a minimum of 12 months. Propensity-matched HV cohorts showed comparable VA (P = 0.61) and mortality rates (P = 0.29) for HINODE and MADIT-RIT. The ND cohort presented a high crossover rate to ICD therapy (6.1%, n = 7/115), and the CRT-D cohort showed elevated mortality rates. The pacing cohort revealed that patients implanted with pacemakers had higher mortality (26.0%) than those with CRT-Pacing (8.4%, P = 0.05). CONCLUSIONS: The mortality and VA event rates of landmark trials are applicable to patients with primary prevention in Japan. Patients who did not receive guideline-indicated CRT devices had poor outcomes.

Comparison of daily anti-hypertensive effects of amlodipine and nifedipine coat-core using ambulatory blood pressure monitoring - utility of "hypobaric curve" and "hypobaric area".

When selecting anti-hypertensives, most physicians do not consider daily blood pressure (BP) variation. To evaluate the effectiveness of anti-hypertensives on the temporal profile of BP, we proposed three new parameters obtained by ambulatory BP monitoring and evaluated these parameters by comparing 5 mg of amlodipine and 40 mg of nifedipine coat-core. Hypobaric values were determined by subtracting BP data collected before administration of the drug from those collected after drug treatment at the corresponding time of day. The hypobaric curve was drawn by plotting the hypobaric values in chronological order, with the time at which the drug was taken set as the starting point. The hypobaric area was the area encircled between the 0 mmHg level line and the hypobaric curve. For amlodipine, the hypobaric areas of systolic blood pressure (SBP) and diastolic blood pressure (DBP) were -19,110 mmHg/min and -10,695 mmHg/min, respectively. Systolic BP decreased -13.3 mmHg, and DBP BP -7.4 mmHg as daily averages. For nifedipine coat-core, the hypobaric areas of SBP and DBP were -32,235 mmHg/min and -18,150 mmHg/min, respectively. Systolic BP decreased -22.3 mmHg and DBP -12.6 mmHg as daily averages. From the hypobaric curves, the trough-to-peak ratios of amlodipine and nifedipine coat-core were measured as 0.67 and 0.60, respectively. The total anti-hypertensive power of nifedipine coat-core, measured by the hypobaric area, was 1.69 times more potent than that of amlodipine. These parameters seem to be useful for evaluating the daily temporal profile of the BP-lowering effects of anti-hypertensive drugs.

Lesion durability after antral pulmonary vein isolation using a radiofrequency hot balloon catheter.

PURPOSE: Antral pulmonary vein isolation (PVI) using a radiofrequency hot balloon catheter (RHB) is a feasible therapeutic option for treating atrial fibrillation (AF). Lesion durability after antral RHB-PVI remains unknown. This study aimed to evaluate lesion durability and the associations between procedural characteristics after antral RHB-PVI. METHODS: A total of 200 patients received antral RHB-PVI using the single-shot technique between April 2016 and March 2018. Antral RHB-PVI was performed following a pre-specified protocol and RHB energy application was performed for a maximum of two times for each PV. Consecutive patients who underwent repeated procedures for recurrence of any type of atrial tachyarrhythmia were enrolled. RESULTS: Twenty-six (13%) patients underwent repeated ablation and 20 patient documented AF recurrence (AF group) and 6 patients documented non-AF recurrence (non-AF group). Repeated ablation was performed at a median (25th, 75th percentiles) of 378 days (217, 487) after the initial procedure and durable PVI was observed in 86 (83.5%) PVs. Durability reached 89.7% when PVI was achieved only using an RHB. In the AF group (79 PVs), durable PVI was observed in 62 (78.5%) PVs, whereas all 24 PVs were still isolated in the non-AF group. The majority of reconnection sites were around the superior PVs. CONCLUSIONS: Antral RHB-PVI shows high lesion durability, especially with both inferior PVs.

Hybrid therapy of radiofrequency catheter ablation and percutaneous transvenous mitral commissurotomy in patients with atrial fibrillation and mitral stenosis.

BACKGROUND: The rhythm control of atrial fibrillation (AF) associated with mitral stenosis (MS) is often difficult using antiarrhythmic drugs (AADs), even after a percutaneous transvenous mitral commissurotomy (PTMC). Few studies have examined the efficacy and safety of simultaneously performing radiofrequency catheter ablation (RFCA) and a PTMC in patients with MS and AF. METHODS: Twenty consecutive patients with drug-resistant AF and rheumatic MS underwent RFCA combined with a PTMC (n = 10; persistent AF-8, long-lasting [>1 year] persistent AF-2; RFCA group) or transthoracic direct cardioversion (DC) following a PTMC (n = 10; persistent AF-7, long-lasting persistent AF-3; DC group). In all patients, the mitral valve morphology was amenable to a PTMC, and more than 2 AADs had been ineffective in maintaining sinus rhythm (SR). In the RFCA group, a segmental pulmonary vein isolation (PVI) was performed in the initial 5 patients, and an extensive PVI was performed in the remaining 5. RESULTS: During a mean follow-up period of 4.0 +/- 2.7 years, 8 patients (80%) in the RFCA group were maintained in SR, as compared to 1 (10%) in the DC group (hazard ratio, 0.16; 95% confidence interval, 0.03 to 0.75; P = 0.008 by the log-rank test). The prevalence of the concomitant use of class I and/or class III AADs was comparable between the 2 groups (P = 0.70). No complications occurred during the procedure or follow-up period in either group. CONCLUSIONS: The hybrid therapy using RFCA and a PTMC was safe and feasible, and significantly improved the AF free survival rate compared to DC following a PTMC.

Isolation of pulmonary vein and superior vena cava for paroxysmal atrial fibrillation in a young adult with left ventricular non-compaction.

We report a 19-year-old male patient with left ventricular non-compaction who presented with atrial fibrillation (AF) and ventricular tachycardia. Ventricular tachycardia was induced by AF with rapid ventricular response, but was prevented by electrical isolation of the pulmonary veins and superior vena cava.

Short-duration triple antithrombotic therapy for atrial fibrillation patients who require coronary stenting: results of the SAFE-A study.

AIMS: We aimed to determine whether shortening the duration of P2Y12 inhibitor therapy can reduce the risk of bleeding without increasing the risk of major adverse cardiovascular events following coronary stenting in patients with atrial fibrillation (AF). METHODS AND RESULTS: The SAFE-A is a randomised controlled trial that compared one-month and six-month P2Y12 inhibitor therapy, in combination with aspirin and apixaban for patients with AF who require coronary stenting. The primary endpoint was the incidence of any bleeding events, defined as Thrombolysis In Myocardial Infarction major/minor bleeding, bleeding with various Bleeding Academic Research Consortium grades, or bleeding requiring blood transfusion within 12 months after stenting. The study aimed to enrol 600 patients but enrolment was slow. Enrolment was terminated prematurely after enrolling 210 patients (72.7±8.2 years; 81% male). The incidence of the primary endpoint did not differ between the one-month and six-month groups (11.8% vs 16.0%; hazard ratio [HR] 0.70, 95% confidence interval [CI]: 0.33-1.47; p=0.35). CONCLUSIONS: The study evaluated the safety of withdrawing the P2Y12 inhibitor from triple antithrombotic prescription one month after coronary stenting. However, enrolment was prematurely terminated because it was slow. Therefore, statistical power was not sufficient to assess the differences in the primary endpoint.

Effect of cardiac resynchronization therapy in isolated ventricular noncompaction in adults: follow-up of four cases.

BACKGROUND: An isolated ventricular noncompaction (IVNC) is an unclassified cardiomyopathy and, despite the increasing awareness of and interest in this disorder, the role of cardiac resynchronization therapy (CRT) remains obscure. OBJECTIVE: The purpose of this study was to clarify the long-term effect of CRT on IVNC in adult patients. METHODS: Four cases of IVNC were included in this study. Before the CRT device was implanted, all four patients (54 +/- 16-year-old, 4 males) presented with symptomatic congestive heart failure. Echocardiography revealed their systolic dysfunction and their left ventricular ejection fraction (LVEF) was 21 +/- 8%. There was also mechanical dyssynchrony observed between the LV septum and free wall area. The QRS duration was "narrow" (112 and 120 ms) in two patients. One patient had been resuscitated from ventricular fibrillation (VF) and two had nonsustained ventricular tachycardia (VT). A CRT defibrillator (CRT-D) was implanted in three patients with VT/VF and a CRT pacemaker (CRT-P) in a patient without VT/VF. The LV lead was positioned in a lateral branch of the coronary sinus where a thickened noncompacted wall existed. RESULTS: During the follow-up period (28 +/- 23 months), their congestive heart failure had improved in terms of the cardiothoracic ratio on the chest X-ray, B-type natriuretic peptide level, LV systolic dimension, and LVEF. No episodes of defibrillation shocks were observed. CONCLUSION: CRT may improve the prognosis and quality-of-life in patients with an IVNC with mechanical dyssynchrony.