Pilot study of bisoprolol 8mg transdermal patch at bedtime before coronary computed tomography angiography.

BACKGROUND: Coronary computed tomography angiography (CCTA) is recommended for first-line evaluation of stable coronary artery disease, and there is a standard protocol to control heart rate (HR) in guidelines. However, time is required to decrease HR to the recommended ≤60 beats per minute (bpm). We investigated whether the bisoprolol 8mg transdermal patch at bedtime on the day before CCTA can achieve a target HR and simplify the CCTA process. METHODS: We randomly assigned 63 patients with an HR of ≥70 bpm and systolic blood pressure ≥120mmHg to a standard protocol group (n=33) or a group (n=30) that applied a bisoprolol 8mg transdermal patch (Bis) at bedtime on the day before CCTA evaluation. The primary endpoint was a change in HR between enrollment in the study and the time of CCTA evaluation. The secondary endpoints were elapsed time from arrival at the CCTA suite to starting CCTA image acquisition, and the rates of oral metoprolol and intravenous landiolol administration (UMIN00035246). RESULTS: Baseline characteristics did not significantly differ between two groups. HR was significantly lower upon arrival at the CCTA suite in Bis, than standard protocol group (67.5±7.8 bpm vs. 75.0±10.6 bpm; p=0.00002), and the amount of elapsed time from arrival to the start of CCTA evaluation was also significantly decreased in Bis group (76.9±34.9min vs. 94.8±29.2min; p=0.0356). Rates of oral metoprolol and intravenous landiolol administration did not significantly differ between two groups (63.3% vs. 83.3%, p=0.143 and 36.7% vs. 60.0%, p=0.12, respectively). CONCLUSIONS: The bisoprolol 8mg transdermal patch lowered HR and decreased the amount of time needed for CCTA, thus streamlining the evaluation process.

Demonstration of a hidden interaction between the aortomitral continuity and the conduction system in a case of idiopathic left ventricular outflow tract ventricular tachycardia.

We describe a case of idiopathic left ventricular outflow ventricular tachycardia. Monomorphic ventricular arrhythmia (VA) with a right bundle branch block morphology and an inferior axis was induced through exercise or isoproterenol infusion. During VA bigeminy, a spiked presystolic potential (PP) preceding the VA with a qrS pattern in the unipolar electrogram was recorded at the aortomitral continuity (AMC). Radiofrequency catheter ablation eliminated the VA despite the persistence of sinus-PP bigeminy. Furthermore, these PP rates were dependent on the preceding sinus rhythm rates. The present case suggests a hidden interaction between the AMC and the conduction system.

Differing relationship between hypercholesterolemia and a bicuspid aortic valve according to the presence of aortic valve stenosis or aortic valve regurgitation.

OBJECTIVES: To assess the difference in hyperlipidemia between patients with bicuspid aortic valve (BAV) and those with a normal aortic valve (NAV), and to compare aortic valve stenosis (AS), with aortic valve regurgitation (AR). METHODS: Among 32 patients with BAV and 142 patients with NAV who underwent aortic valve replacement, 81 patients had AR and 91 patients had AS. The preoperative clinical characteristics were compared between the BAV and NAV patients. Patients with replacement of the ascending aorta were included, and those who underwent combined valvular surgery, coronary artery bypass grafting, or statin treatment were excluded. RESULTS: The proportions of females patients (p = 0.42), patients with diabetes (p = 0.26) and patients on dialysis (p = 0.69) were similar in the two groups. Mean age was significantly lower, the mean diameter of the ascending aorta was significantly larger, and the rate of surgical intervention for the ascending aorta was significantly higher in the BAV group than in the NAV group (all p < 0.0001). The mean levels of low-density lipoprotein cholesterol (LDL) (p < 0.0001) and total cholesterol (TC) (p = 0.0003) were significantly higher in the BAV group than in the NAV group, in the analysis of only patients with AS, whereas these levels did not differ significantly between the groups, when only patients with AR were considered. CONCLUSION: BAV with AS is associated with hypercholesterolemia. However, BAV with AR was not associated with hypercholesterolemia.

An unmappable ventricular tachycardia in the arrhythmogenic right ventricular cardiomyopathy: elucidation of critical isolated delayed components with high-resolution electroanatomical mapping.

Unmappable ventricular tachycardia (VT) is a challenge in the management of arrhythmogenic right ventricular cardiomyopathy (ARVC). We report a feasible strategy for a curative ablation. In the present case with ARVC, the clinical VT showed a single morphology of left bundle branch block with inferior axis. Neither activation mapping nor entrainment mapping could be done because of instability of the haemodynamics. Furthermore, pace mapping could not be obtained due to electrically unexcitable scars covering with the RV. We found isolated delayed components (IDCs) in the diastolic phase recorded within the scar areas. Electroanatomical mapping (CARTO) with tiered decreasing voltage definition revealed that IDCs were delineated on the narrow conducting channels along or between the complete scars (amplitude < or =0.1 mV). Isolated delayed components on the narrow channels were targeted under the guidance with CARTO. After 11 radiofrequency applications, the clinical VT was eliminated. Moreover, epsilon waves recorded on the 12-lead electrocardiogram disappeared. No ventricular tachyarrhythmia was recognized at 6-month follow-up. Isolated delayed component ablation with high-resolution CARTO map was feasible and provided a curative approach in the treatment of an unmappable VT in ARVC.

Ventricular late potential in patients with apparently normal electrocardiogram; predictor of Brugada syndrome.

BACKGROUND: Brugada syndrome can be overlooked due to its dynamic change in its electrocardiogram (ECG) manifestation. We hypothesized that positive ventricular late potential (VLP) in patients with nonspecific ECG would predict the inducible coved ST elevation (type-1 Brugada ECG) and the patients at high risk. METHODS: Thirty-four patients of nonspecific ECG without structural heart disease were eligible for this study. All patients were referred for evaluation of syncopal episodes and/or cardiac arrest and/or frequent episodes of ventricular premature contractions. We assessed the correlation between baseline VLP and the alteration to a drug-induced type-1 Brugada ECG, and also evaluated the diagnostic accuracy of positive VLP in normal ECG subjects for the appearance of a drug-induced type-1 Brugada ECG. RESULTS: Twenty-one patients presented positive VLP and 13 patients showed negative VLP. Parameters of VLP (fQRSd, RMS(40), LAS(40)) presented significant correlation with the alteration to a type-1 ECG by pilsicainide. VLP demonstrated high sensitivity and negative predictive value for the prediction of type-1 Brugada ECG. Furthermore, in their follow-up, at least two cases of ventricular fibrillation were recognized in 21 of positive VLP patients with apparently normal ECGs. CONCLUSIONS: VLP in apparently normal ECG can predict the alteration to a drug-induced type-1 Brugada ECG and unmask the patients at risk.

The results of a new distal protection method in intervention for chronic total occlusion of the superficial femoral artery.

Aims. To determine the efficacy of a new distal protection method in SFA CTO interventions. Methods and Results. From June 2003 to February 2009, ninety-two consecutive, chronic total occlusions of superficial femoral arteries were treated with catheter-based intervention using a bidirectional approach. Nine of these cases were managed with our original, distal protection method, based on symptoms, angiographic images, wire resistance, and intravascular ultrasound images. The average age was 73 years; eight patients were male. The mean occlusion length was 17.1 cm. A distal protection balloon was inserted from the retrograde sheath in the popliteal artery and placed distal to the occluded lesion after successful wire crossing. Lesion dilatation with a balloon was performed antegradely and debris was removed by 6Fr. guiding catheter. Debris was retrieved from all lesions, consisting mainly of thrombus. Where we decided not to use the distal protection method, there was no distal thromboembolism. Conclusion. In SFA-CTO intervention, the risk of distal embolization is 10%, which can be anticipated and eliminated by the distal protection method.

Catheter ablation of fatal ventricular tachyarrhythmias storm in acute coronary syndrome--role of Purkinje fiber network.

Ventricular fibrillation (VF) or ventricular tachycardia (VT) storm is a life-threatening arrhythmia. Antiarrhythmic drugs (AADs) are not necessarily effective to rescue life from such conditions. Catheter ablation (CA) targeting triggering premature ventricular contractions (PVCs) of VF or VT that originates from Purkinje fiber network (PFN) is reported to be effective, especially in idiopathic patients. However, in condition of acute coronary syndrome (ACS), the efficacy of CA is not well understood. To clarify the usefulness of CA as an alternative way to AADs, we performed CA in four patients with VF or VT storm. The Purkinje potential was seen just before the myocardial ventricular wave during sinus rhythm that became more prominent and double components during the initiating PVC at the targeted area. Following CA, spontaneous episodes of VF or VT were no longer observed. CA is an efficacious way to bail out PFN-related VF or VT storm even in ACS.

Nifekalant and disopyramide in a patient with short QT syndrome: evaluation of pharmacological effects and electrophysiological properties.

We assessed several pharmacological effects on electrocardiogram parameters and effective refractory period (ERP) in a patient with a short QT syndrome (SQTS). Pharmacological challenge tests revealed that disopyramide and selective I(kr) blocker, nifekalant normalized QT interval, and ERP of the atrial and ventricular myocardium. This study suggested that disopyramide and nifekalant should be feasible for the drug treatment of the SQTS. Moreover, QT interval was paradoxically prolonged at higher heart rates induced with isoproterenol infusion or an exercise test, although the mechanism of this QT prolongation remains to be investigated.

Acute-on-chronic massive pulmonary embolism treated with 3-loop snare.

A 70-year-old man presented with acute massive pulmonary embolism (PE). His clinical condition deteriorated despite regular heparin and thrombolytic agent treatment, and he eventually developed cardiogenic shock. A thrombus originating from the inferior vena cava was detected and acute-on-chronic embolization resulted, with an unusual clinical course. Aggressive catheter thrombectomy with pigtail rotation failed to fragment the organized thrombus, but it was successfully removed by a 3-loop snare device combined with guiding catheter under percutaneous cardiopulmonary support.

[Initial and long term outcomes of stent implantation for iliac compression syndrome].

OBJECTIVES: The initial and long term outcome of stenting in the iliac vein were investigated in patients with iliac compression syndrome. METHODS: Iliac compression syndrome was diagnosed with venography and intravascular ultrasonography that demonstrated severe stenosis at the iliac venous compression site. Fourteen patients with symptomatic iliac compression syndrome were treated with stent implantation. The patency of the stents was examined at short and long term follow-up examinations. RESULTS: Thirteen patients presented with left iliac venous compression and only one patient presented with right iliac venous compression. Twelve of the 14 patients had acute deep venous thrombosis, so temporary vena cava filter implantation was performed during the procedure in these 12 patients. Procedural success was defined as less than 50% stenosis after stent implantation with good flow and without major complication (death, surgical repair for vein, or symptomatic pulmonary embolization). Procedural success was achieved in 13 of 14 patients, and these 13 patients showed improvement of symptoms. In the unsuccessful case, the compression site was resolved by stenting, but good flow was not obtained due to remaining femoral vein occlusion. The self-expandable stent was used for 6 patients, and the balloon-expandable stent was used for 8 patients. Angiographic or ultrasonographic follow up was performed in 10 patients at mean follow up of 8 months, but no restenosis was documented. CONCLUSIONS: Stent implantation for symptomatic iliac compression syndrome is a safe and effective procedure to resolve venous disease symptoms. Despite the small number of patients, long term outcome has been excellent in this study.

Case report: Focal ablation for atrial fibrillation originating from the inferior vena cava and the posterior left atrium.

We identified a case of paroxysmal atrial fibrillation (AF) originating from inferior vena cava (IVC) and the low-posterior left atrium (LA). Both foci, the IVC and the low-posterior LA, simultaneously served not only as trigger but also as driver for maintenance of AF. During AF, the IVC and the low-posterior LA continuously demonstrated the rapid and fractionated potentials that exit into both atria with conduction block. Focal ablation for ectopic beats within the IVC and the low-posterior LA completely eliminated the storm of AF.

Two atrial reentrant tachycardias originating from the superior vena cava: electrophysiological characteristics and radiofrequency ablation.

A case with two different types of atrial reentrant tachycardia of superior vena cava (SVC) origin is presented. Recent clinical studies have shown that the origin of focal atrial tachycardia typically lies in the venous structures connecting to both atria--the coronary sinus, the superior and inferior vena cava, and the pulmonary vein. These foci have atrial muscle fiber extensions which have electrophysiological characteristics essential to generation of focal ectopic firing. However, little is known about reentrant mechanism of these venous structures. In this report, we present a case of two atrial tachycardias (SVT1 and SVT2) independently originating from the SVC. SVT1 had 430 ms of tachycardia cycle length, and SVT2 had 390 ms of tachycardia cycle length. Both of them showed the character of reentry, and their earliest activations were recorded in the SVC. They were successfully eliminated by focal radiofrequency ablation in the SVC.

Catheter ablation for an incessant form of antiarrhythmic drug-resistant ventricular fibrillation after acute coronary syndrome.

A 77-year-old man was admitted with an acute coronary syndrome (ACS), severe heart failure (HF), and repeated ventricular fibrillation (VF) episodes. A single premature ventricular complex (PVC) induced ventricular tachycardia (VT), which degenerated to VF reproducibly. This PVC was eliminated by catheter ablation at the left ventricular posteroseptal region where double Purkinje potentials preceding the ventricular wave had been recorded. The electrical storm disappeared, and programmable stimulation failed to induce any tachyarrhythmias after the ablation. A Purkinje fiber network-related PVC served as a trigger and as a substrate for VT and VF in a case of ACS with HF.

Bundle brunch reentrant ventricular tachycardia with two distinct conduction patterns in a patient with complete right bundle branch block.

We report a rare case of bundle branch reentrant ventricular tachycardia [BBRVT]. A 67-year-old female was admitted for management of wide QRS tachycardia (right bundle branch block [RBBB] and a southwest axis). The mapping procedure revealed the tachycardia circuit consisted of the left anterior fascicle (LAF) as an antegrade, and the right bundle as a retrograde pathway. She presented RBBB during sinus rhythm. LAF ablation changed the tachycardia configuration to a northwest axis and prolonged the cycle length. Left posterior fascicle ablation terminated the tachycardia, and complete atrioventricular block occurred, which showed the unidirectional conduction over the right bundle.

Relationship between ST-segment morphology and conduction disturbances detected by signal-averaged electrocardiography in Brugada syndrome.

BACKGROUND: Although arrhythmogenesis of Brugada syndrome is still unknown, it has been reported to be associated with conduction disturbances. Two ST-segment morphologies (coved and saddle-back patterns) have been described in this syndrome. No study has sought to determine which morphology has stronger conduction disturbances, thereby associating with life-threatening events. METHODS: Forty-six patients who presented the Brugada-type ECG with either of a characteristic coved (n = 25) or saddle-back (n = 21) pattern of ST-segment morphology underwent signal-averaged ECG (SAECG). SAECG parameters, and the history of life-threatening events defined as syncope or aborted sudden death, were compared between groups. RESULTS: Although filtered QRS duration did not differ between groups, the incidence of late potentials in the coved group was higher than in the saddle-back group (22 patients (88%) versus 4 patients (19%); P < 0.01), showing lower RMS40 and longer LAS40. Life-threatening events occurred in 17 patients (68%) in the coved group and 7 patients (33%) in the saddle-back group (P = 0.02). CONCLUSION: The coved pattern of ST segment was more closely related to conduction disturbances than the saddle-back pattern in patients with Brugada-type ECG. Life-threatening events were more common in patients with the coved ST-segment elevation. Conduction disturbances in the coved pattern of ST segment may reflect a substrate of arrhythmogenesis in Brugada syndrome.

Evaluation of bi-atrial pacing and single site right atrial pacing for the prevention of atrial fibrillation.

Atrial resynchronization resulting from simultaneous pacing of the atria may adjust inter- or intra-atrial asynchrony and prevent atrial fibrillation (AF). The purpose of this study was to assess the efficacy of bi-atrial pacing (BAP) in preventing AF, and the safety of this system. The effect of BAP was compared with single site right atrial pacing (RAP) in 6 patients with sick sinus syndrome and paroxysmal AF in a prospective switchover trial. P wave duration was significantly reduced during BAP (p<0.01). Pacing threshold, atrial wave amplitude and the lead impedance presented no significant differences at implant, 1 week and 3 months after implantation, respectively (NS). The number of AF episodes significantly decreased during both RAP and BAP compared with the control (p<0.01). Although the number of premature atrial contractions was significantly less during BAP than RAP (p<0.05), there were no significant differences of AF episodes between the two. The percentage of pacing was achieved in only 70% during both pacing modes. BAP was safe and reliable in this follow-up period and can prevent AF. These findings provide encouragement for further study and observation of BAP to prevent AF.