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1.
JACC Clin Electrophysiol ; 7(10): 1297-1308, 2021 10.
Article in English | MEDLINE | ID: mdl-34217659

ABSTRACT

OBJECTIVES: This study investigates the effect of stellate ganglion (SG) phototherapy in healthy participants and assesses its efficacy in suppressing electrical storm (ES) refractory to antiarrhythmic drugs and catheter ablation. BACKGROUND: Modulation of the autonomic nervous system has been shown to be an effective adjunctive therapy for ES. METHODS: Ten-minute SG phototherapy was performed twice weekly for 4 weeks in 20 healthy volunteers. To evaluate the acute and chronic effects of SG phototherapy, heart rate variability and serum concentrations of adrenaline, noradrenaline, and dopamine were obtained before phototherapy, immediately after the first phototherapy session, after 8 sessions of phototherapy, and 3 months after the first phototherapy session. In addition, the efficacy of SG phototherapy was evaluated in 11 patients with ES refractory to medication, sedation, and catheter ablation. RESULTS: In healthy participants, serum adrenaline concentration significantly decreased after phototherapy, whereas low-frequency power/high-frequency power significantly decreased during phototherapy. Moreover, the effect on heart rate variability did not last beyond 3 months. In the clinical pilot study, 7 patients had a suppression of ES after SG phototherapy; however, without maintenance therapy, 2 patients had a recurrence of ventricular arrhythmias. Furthermore, it did not control ES in 4 patients. CONCLUSIONS: SG phototherapy reduced sympathetic activity and may be a safe and effective adjunctive therapy to control ES in some patients, but its long-term efficacy remains unknown. Chronic phototherapy might help reduce ES recurrence.


Subject(s)
Stellate Ganglion , Tachycardia, Ventricular , Arrhythmias, Cardiac , Humans , Lasers , Phototherapy , Pilot Projects
2.
J Cardiovasc Electrophysiol ; 31(2): 440-449, 2020 02.
Article in English | MEDLINE | ID: mdl-31916643

ABSTRACT

INTRODUCTION: The voltage map during sinus rhythm (SR) is a cornerstone of substrate mapping (SM) in scar-related ventricular tachycardia (VT) and frequently used with pace mapping (PM). Where to conduct PM is unclear in cases of an extensive or unidentified substrate. Conduction properties are another aspect incorporated by SM, and conduction slowing has gained interest as being related to successful ablation, although its mechanism has not been elucidated. We aimed to investigate the relationship between SR conduction properties and VT isthmuses. METHODS: Nineteen patients (mean age, 62 years) who underwent VT ablation with voltage mapping and PM were reviewed. Isochronal late activation maps (ILAMs) with eight zones were reconstructed and sequentially named from one to eight according to the SR propagation. Good PM sites were superimposed on ILAMs, and the isthmus was defined using different pacing latencies. ILAM properties harboring isthmuses were investigated. RESULTS: Twenty-eight ILAMs (13 epicardium, 1 right ventricular [RV], and 14 left ventricular [LV] endocardium) were reviewed. Eighteen isthmuses of 24 target VTs were identified, in which the proximal ends were in a later zone than the distal ends (zone 6 vs 4; P < .001), suggesting a reverse isthmus vector to the SR. The conduction velocity of the zone involving the distal isthmus was significantly lower than that of the SR preceding zone (0.40 vs 1.30 m/s; P < .001). SR conduction velocity decelerated by 69.5% (range 59.7%-74.5%) before propagating into the isthmus area. CONCLUSION: Conduction slowing area during SR were related with the exit portion of the VT isthmuses.


Subject(s)
Heart Conduction System/physiopathology , Heart Rate , Tachycardia, Ventricular/physiopathology , Action Potentials , Adult , Aged , Aged, 80 and over , Catheter Ablation , Electrophysiologic Techniques, Cardiac , Female , Humans , Male , Middle Aged , Retrospective Studies , Tachycardia, Ventricular/diagnosis , Tachycardia, Ventricular/surgery , Time Factors , Tokyo
3.
Circ Arrhythm Electrophysiol ; 12(6): e007415, 2019 06.
Article in English | MEDLINE | ID: mdl-31113233

ABSTRACT

Background His-bundle pacing (HBP) is a physiological form of pacing. Although high capture thresholds are common, few predictors of low HBP threshold have been determined. We aimed to identify electrophysiological predictors. Methods Fifty-one patients (53% with atrioventricular block) underwent HBP for bradycardia with an intrinsic QRS duration of <120 ms. Attempts to anchor the HBP lead were guided by unipolar His-bundle electrograms (HB EGMs) recorded with an electrophysiology recording system. Patients were followed-up for >6 months. Results In total, 153 attempts at anchoring the HBP lead were made, of which, 45 achieved acceptable HBP thresholds (≤2.5 V at 1 ms). The amplitude of negative deflection in HB EGM and the selective HBP form at fixation were independently associated with achieving an acceptable threshold. A negative amplitude of ≥0.060 mV in HB EGM was determined as the optimal value for identifying the acceptable threshold. This deep negative HB EGM was recorded with an HBP threshold of 1.4±1.3 V (in 34 attempts), significantly lower than that of positive HB EGM without deep negative deflection (2.8±1.3 V, in 31 trials; or >5 V, in 38 trials). The permanent HBP lead remained with deep negative (≥0.060 mV) or positive HB EGMs in 28 and 14 patients, respectively, and with positive or negative HB injury current in 19 and 23 patients, respectively. During follow-up, increased HBP threshold of >1 V was significantly more prevalent in the positive HB EGM group. The HBP thresholds of deep negative HB EGM and HB injury current, but not of the selective HBP group, were significantly lower than the other subgroups during follow-up. Conclusions Deep negative HB EGM at fixation was associated with an excellent short-term HBP threshold, similar to HB injury current. Analysis of unipolar HB EGM postfixation may enable prediction of permanent HBP threshold.


Subject(s)
Action Potentials , Atrioventricular Block/diagnosis , Atrioventricular Block/therapy , Bradycardia/diagnosis , Bundle of His/physiopathology , Cardiac Pacing, Artificial , Electrophysiologic Techniques, Cardiac , Heart Rate , Aged , Aged, 80 and over , Atrioventricular Block/physiopathology , Bradycardia/physiopathology , Bradycardia/therapy , Cardiac Pacing, Artificial/adverse effects , Female , Humans , Male , Predictive Value of Tests , Prospective Studies , Registries , Risk Factors , Time Factors , Treatment Outcome
5.
Circ Arrhythm Electrophysiol ; 8(2): 381-9, 2015 Apr.
Article in English | MEDLINE | ID: mdl-25716991

ABSTRACT

BACKGROUND: In patients with mechanical aortic and mitral valves and left ventricular tachycardia, catheter ablation may be prevented by limited access to the left ventricle. METHODS AND RESULTS: In our series of 6 patients, 2 patients underwent direct surgical ablation and 4 underwent epicardial catheter ablation via a pericardial window. All patients had abnormal low voltage areas with fractionated or delayed isolated potentials on the apical epicardium. Most of the ventricular tachycardias were targeted by pace mapping. Sites with a good pace match or abnormal electrograms were ablated using an irrigated radiofrequency ablation catheter. A microscopic pathological evaluation of the resected tissue from 2 of the open-heart ablation patients revealed dense fibrosis on the epicardium compared with the endocardium, supporting the feasibility of an epicardial ablation for the ventricular tachycardia. CONCLUSIONS: Epicardial catheter ablation of ventricular tachycardia is a potentially useful therapy in patients who have mechanical aortic and mitral valves.


Subject(s)
Aortic Valve/surgery , Catheter Ablation/methods , Heart Valve Prosthesis Implantation/instrumentation , Heart Valve Prosthesis , Heart Ventricles/surgery , Mitral Valve/surgery , Pericardial Window Techniques , Pericardium/surgery , Tachycardia, Ventricular/surgery , Aged , Cardiac Catheters , Catheter Ablation/instrumentation , Electrocardiography , Electrophysiologic Techniques, Cardiac , Feasibility Studies , Heart Ventricles/physiopathology , Humans , Male , Middle Aged , Pericardium/physiopathology , Prosthesis Design , Retrospective Studies , Stroke Volume , Tachycardia, Ventricular/diagnosis , Tachycardia, Ventricular/etiology , Tachycardia, Ventricular/physiopathology , Therapeutic Irrigation/instrumentation , Treatment Outcome , Ventricular Function, Left
6.
BMC Res Notes ; 7: 677, 2014 Sep 27.
Article in English | MEDLINE | ID: mdl-25260975

ABSTRACT

BACKGROUND: Beauveria bassiana is an entomopathogenic fungus and is a rare cause of keratitis. We present a case of fungal keratitis caused by B. bassiana that was diagnosed by in vivo confocal microscopy and in vitro corneal cultures. In addition, we determined the temperature- and drug-sensitivities of the isolated strain of B. bassiana. CASE PRESENTATION: A 59-year-old Japanese man with a 2-month history of keratitis was examined by slit-lamp biomicroscopy, in vivo confocal microscopy, and histology and cultures of corneal scrapings. The corneal scrapings were used to determine the minimal inhibitory concentrations of different antifungal drugs and also to determine the temperature-sensitivity. In vivo confocal microscopy and histological examinations showed filamentous fungal keratitis. The characteristics of the fungal growth indicated that the keratitis was caused by B. bassiana. The keratitis responded poorly to systemic and topical voriconazole and to natamycin ointment. However, it was resolved after changing the natamycin to micafungin combined with surgical debridement. The isolated strain was sensitive to itraconazole, miconazole, micafungin, voriconazole, and resistant to flucytosine and fluconazole. It was moderately sensitive to amphotericin B, and natamycin. After 7 days in culture, the isolate grew small white colonies at 25 °C, very small colonies at 35 °C and 37 °C. CONCLUSION: The drug-sensitivity and temperature-sensitivity profiles of B. bassiana should be helpful in the treatment of B. bassiana keratitis. Therapeutic surgery may be helpful for mycotic keratitis poorly responsive to medical therapy alone.


Subject(s)
Antifungal Agents/therapeutic use , Beauveria/pathogenicity , Keratitis/drug therapy , Keratitis/microbiology , Temperature , Beauveria/isolation & purification , Humans , Infant, Newborn , Male , Microscopy, Confocal
7.
Europace ; 14(5): 734-40, 2012 May.
Article in English | MEDLINE | ID: mdl-22048994

ABSTRACT

AIMS: Little is known about sustained monomorphic ventricular tachycardia (SMVT) associated with dilated-phase hypertrophic cardiomyopathy (DHCM). The purpose of this study was to clarify the clinical characteristics and effectiveness of catheter ablation for SMVTs in DHCM patients. METHODS AND RESULTS: Five patients with DHCM (mean age; 67.0 years old, five males) who underwent catheter ablation for drug-refractory SMVTs were included the study. Four of five patients suffered from electrical storm. When the endocardial ablation failed, epicardial and/or intracoronary ethanol ablation, or surgical cryoablation was performed. We reviewed all ablation procedures and electrocardiogram (ECG) of targeted SMVTs. A total of 13 SMVTs were targeted for ablation. Mechanism of all ventricular tachycardias (VTs) was diagnosed as reentry. Endocardial ablation successfully eliminated all VTs in two patients. The remaining three patients needed epicardial ablation, intracoronary ethanol ablation, and surgical cryoablation. All but one VT arose from the basal septum, basal anterior to anterolateral left ventricle (LV). Although the ECGs demonstrated similar features of idiopathic outflow or mitral annulus VTs reflecting the origins, there were characteristic multiple QRS deflections. Following the ablation, four (80%) of the five patients are free from VT recurrence during 18 months of the follow-up period. CONCLUSIONS: In DHCM patients, VT circuits predominantly distributed in the basal septum and the basal anterior to anterolateral LV. In addition to the endocardial ablation, alternative approaches were required in some patients.


Subject(s)
Cardiomyopathy, Hypertrophic/complications , Cardiomyopathy, Hypertrophic/physiopathology , Catheter Ablation/methods , Tachycardia, Atrioventricular Nodal Reentry , Aged , Cryosurgery/methods , Electrophysiologic Techniques, Cardiac/methods , Ethanol/therapeutic use , Follow-Up Studies , Humans , Male , Middle Aged , Postoperative Complications/physiopathology , Tachycardia, Atrioventricular Nodal Reentry/complications , Tachycardia, Atrioventricular Nodal Reentry/physiopathology , Tachycardia, Atrioventricular Nodal Reentry/surgery
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