Clinical and electrophysiologic predictors of ventricular tachyarrhythmia recurrence in patients with implantable cardioverter defibrillators

INTRODUCTION: Not all patients experience recurrent sustained ventricular tachyarrhythmias after placement of an implantable cardioverter defibrillator (ICD). We evaluated the clinical and electrophysiologic predictors of ventricular tachycardia (VT) and ventricular fibrillation (VF) recurrence following ICD implantation. METHODS AND RESULTS: Consecutive patients (n = 133) underwent 4 +/- 3 serial electrophysiologic studies (EPS) over 50 +/- 26 months following ICD implantation. Sustained VT/VF could always be induced during follow-up EPS in 49 patients; sustained VT/VF was sometimes induced during follow-up EPS in 47 patients; and sustained VT/VF could never be induced during follow-up EPS in 37 patients. Spontaneous VT/VF requiring ICD therapy occurred in 107 patients during follow-up. Patients with sustained VT/VF that was always inducible or sometimes inducible during follow-up experienced more frequent episodes of VT/VF following ICD implant (20.5, 95% CI 12.7-33.0; and 17.8, 95% CI 11.3-28.1 episodes/patient respectively; vs 3.0, 95% CI 2.0-4.6 episodes/patient for patients with VT/VF never induced, P < 0.001). Inducibility of sustained VT/VF post-ICD implant (P < 0.001) and sustained VT as the presenting arrhythmia (P = 0.02) were independent predictors of spontaneous VT/VF recurrence. CONCLUSION: Reproducibly inducible VT/VF following ICD implantation predicts a high probability of VT/VF recurrence and identifies a cohort of patients who experience frequent episodes of VT/VF over time. Persistent noninducibility of sustained VT/VF identifies a group of patients who experience no or very few episodes of VT/VF recurrence.     

Incidence of nonsustained and sustained ventricular tachyarrhythmias in patients with an implantable cardioverter defibrillator

INTRODUCTION: Nonsustained ventricular tachycardia (NSVT) is a frequent phenomenon in some patients with heart disease, but its association with sustained ventricular tachycardias (ventricular tachycardia [VT]/ventricular fibrillation [VF]) is still not clear. The aim of this study was to determine whether NSVT incidence was associated with sustained VT/VF in patients with an implantable cardioverter defibrillator (ICD). METHODS AND RESULTS: Retrospective data analysis was conducted in 923 ICD patients with a mean follow-up of 4 months. NSVT and sustained VT/VF were defined as device-detected tachycardias. The incidence rates of NSVT and sustained VT/VF as well as ICD therapies were determined as episodes per patient. The NSVT index was defined as the product of NSVT episodes/day times the mean number of beats per episode, i.e., total beats/day. The NSVT index peak was defined as the highest value on or prior to the day with sustained VT/VF episodes. Patients (n = 393) with NSVT experienced a higher incidence of sustained VT/VF (17.2 +/- 63.0 episodes/patient) and ICD therapies (15.2 +/- 61.4 episodes/patient) than patients (n = 530) without NSVT (sustained VT/VF: 0.5 +/- 6.6 and therapies: 0.5 +/- 5.6; P < 0.0001). Approximately 74% of NSVT index peaks occurred on the same day or <3 days prior to sustained VT/VF episodes. The index was higher for peaks < or =3 days prior to the day with sustained VT/VF (94.3 +/- 140.1 total beats/day) than for peaks >3 days prior to the day with sustained VT/VF (32.7 +/- 55.9 total beats/day; P < 0.0001). CONCLUSION: ICD patients with NSVT represent a population more likely to experience sustained VT/VF episodes with a temporal association between an NSVT surge and sustained VT/VF occurrence.     

Electrophysiologic manifestations of ventricular tachyarrhythmias provoking appropriate defibrillator interventions in high-risk patients with hypertrophic cardiomyopathy

Introduction: Our objective was to determine features of ventricular tachyarrhythmias triggering appropriate implantable cardioverter-defibrillator (ICD) interventions in hypertrophic cardiomyopathy (HCM).
Methods and Results: The study cohort was 68 high-risk HCM patients who received ICDs for primary sudden cardiac death prevention from 1995 to 2003. All episodes of sustained ventricular tachyarrhythmias identified by stored intracardiac electrograms were analyzed. Nine patients had 51 episodes of sustained ventricular tachyarrhythmic events that required device therapy (mean follow-up, 3.4 ± 2.2 years; cumulative event rate, 3.2% per year): five had 47 episodes of monomorphic ventricular tachycardia (VT); four each had one episode of ventricular fibrillation (VF). Sinus tachycardia or atrial fibrillation was the initiating rhythm in five of nine patients and in 43 of 51 episodes of events. Of the 17 episodes of monomorphic VT detected in the VT zone, 16 (94%) were terminated by antitachycardia pacing. Thirty episodes of monomorphic VT were detected in the VF zone and were terminated by defibrillation.
Conclusion: Sustained monomorphic VT is common in a high-risk cohort with HCM. Sinus tachycardia is often the initiating rhythm, suggesting that high sympathetic drive may be proarrhythmic when a susceptible substrate is present. Antitachycardia pacing is highly effective in terminating VT in this patient population.     

Initial clinical experience with a new arrhythmia detection algorithm in dual chamber implantable cardioverter defibrillators.

AIM: Inappropriate therapy, due to poor discrimination of supraventricular tachycardia (SVT) from ventricular tachycardia (VT) remains a major problem in patients with an implantable cardioverter defibrillator (ICD). Theoretically, the addition of atrial sensing in discrimination algorithms should improve this differentiation. The aim of the study is to evaluate the performance of a new tachycardia discrimination algorithm, SMART Detection. METHODS AND RESULTS: Twenty-six patients received a non-thoracotomy ICD system (Phylax AV, Biotronik, Germany). All documented spontaneous arrhythmia episodes were analyzed. During a mean follow-up of 8 months, a total number of 139 events with stored electrograms were recorded in 12 patients. The final diagnosis was ventricular fibrillation (VF) or polymorphic VT (n=20), monomorphic VT (n=69), SVT (n=26), other ventricular arrhythmia (n=3) and T wave oversensing (n=21). In 6 episodes a dual tachycardia was present. Considering SVT episodes, inappropriate therapy occurred in 2 cases of atrial flutter due to stable ventricular rate (<30 ms), 1 case of atrial tachycardia and 2 cases of sinus tachycardia due to a sudden onset (> 10%). CONCLUSION: With the SMART Detection algorithm, discrimination of VT from SVT achieved a sensitivity of 100%, with an accuracy of 95.6% for all ventricular arrhythmias. In the case of SVT, the algorithm appropriately detected and inhibited therapy in 88% of atrial fibrillation.     

Prevalence, predictors, and mortality significance of the causative arrhythmia in patients with electrical storm

INTRODUCTION: Electrical storm (ES) is characterized by either refractory ventricular tachycardia (VT) or ventricular fibrillation (VF). However, little is known about the prevalence, predictors, and mortality implications of the causative arrhythmia in ES. We sought to assess the prevalence, predictors, and survival significance of VT and VF as the causative arrhythmia of ES in implantable cardioverter defibrillator (ICD) patients. METHODS AND RESULTS: Consecutive patients from January 2000 to December 2002 who presented to the ICD clinic with > or = 2 separate ventricular arrhythmic episodes requiring shock within 24 hours were included in the study. ICD interrogation confirmed the number of shocks and provided electrograms for interpretation of the causative arrhythmia. Patients were grouped as VF or VT according to the causative arrhythmia. Their prevalence, predictors, and mortality rates were compared. Of 2,028 patients assessed in the ICD clinic, 208 (10%) presented with ES. VF was the cause of ES in 99 of 208 patients, for an overall prevalence of 48%. Original ICD indication, coronary artery disease, and amiodarone therapy were predictive for the causative arrhythmia. There was no mortality difference between the VT and VF groups; however, both groups had significantly increased mortality compared to a control ICD population without ES. CONCLUSION: VF is the causative arrhythmia for a sizable proportion of patients with ES. The initial ICD indication, coronary artery disease, and amiodarone therapy are predictors of the causative arrhythmias in ES. There does not appear to be any mortality difference between ES patients with VT and VF, but mortality is increased in patients with ES versus control ICD patients without ES.     

Predictive value of ventricular arrhythmia inducibility for subsequent ventricular tachycardia or ventricular fibrillation in Multicenter Automatic Defibrillator Implantation Trial (MADIT) II patients.

In the Multicenter Automatic Defibrillator Implantation Trial (MADIT) II, implantable cardioverter-defibrillator (ICD)-randomized patients underwent electrophysiologic testing. Both inducible and noninducible patients received an ICD. We correlated inducibility with the occurrence of subsequent ventricular tachycardia (VT) or ventricular fibrillation (VF). Intracardiac ICD electrograms for subsequent events were analyzed to categorize the spontaneous arrhythmia as VT or VF. The two-year Kaplan-Meier event rate for VT in inducible patients was 29.0% versus 19.3% in noninducible patients. However, ICD therapy for spontaneous VF was less common at two years in inducible patients (3.2%) than in noninducible patients (8.6%). In the MADIT II study, inducibility predicted an increased likelihood of VT but decreased VF. OBJECTIVES: We correlated electrophysiologic inducibility with spontaneous ventricular tachycardia (VT) or ventricular fibrillation (VF) in the Multicenter Automatic Defibrillator Implantation Trial (MADIT) II. BACKGROUND: In the MADIT II study, 593 (82%) of 720 implantable cardioverter-defibrillator (ICD) randomized patients underwent electrophysiologic testing. Patients received an ICD whether they were inducible or not. METHODS: A "standard" inducibility definition included sustained monomorphic or polymorphic VT induced with three or fewer extrastimuli or VF induced with two or fewer extrastimuli. We compared a narrow inducibility definition (only monomorphic VT) and a broad definition (standard definition plus VF with three extrastimuli). We used ICD-stored electrograms to categorize spontaneous VT or VF. RESULTS: Inducible patients (standard definition) had a greater likelihood of experiencing ICD therapy for VT than noninducible patients (p = 0.023). Unexpectedly, ICD therapy for spontaneous VF was less common (p = 0.021) in inducible patients than in noninducible patients. The two-year Kaplan-Meier event rate for VT or VF was 29.4% for inducible patients and 25.5% for noninducible patients. Standard inducibility did not predict the combined end point of VT or VF (p = 0.280, by log-rank analysis). The narrow inducibility definition outperformed the standard definition, whereas the broad definition appeared inferior to the standard definition. CONCLUSIONS: In the MADIT II study patients, inducibility was associated with an increased likelihood of VT. Noninducible MADIT II study subjects using this electrophysiologic protocol had a considerable VT event rate and a higher VF event rate than inducible patients. Induction of polymorphic VT or VF, even with double extrastimuli, appears less relevant than induction of monomorphic VT.     

射频消融治疗室性早搏触发特发性室性心动过速／心室颤动的病例分析

目的探讨射频消融治疗在室性早搏（室早）触发特发性室性心动过速／心室颤动（室速／室颤）中的作用。方法总结3例由室早触发室速／室颤的治疗经验,1例对室早进行射频消融（RF—CA）并植入心律转复除颤器（ICD）,另1例经射频消融未完全消除室早而选择植入ICD,第3例经射频消融成功消除室早,未再发室颤。结果随访2年,3例患者均存活,ICD未再记录到室速／室颤。结论在室早触发室速／室颤病例中,应分析室早与室速／室颤的相关性,给予个体化治疗,射频消融室早可以消除／减少晕厥和室颤的发作。     

Brugada综合征患者心律失常及临床特点分析

目的通过动态心电图(Holter)检查、置入式心脏复律除颤器(ICD)分析并综合患者临床情况,研究Brugada综合征(Brs)患者心律失常事件发生特征及临床特点。方法对我院近5年诊断的12例Brs住院患者的临床情况进行随访观察;均行Holter检查分析心律失常事件发生特征;根据ICD的随访资料,分析室颤发作的时间特征。结果 Holter显示,其中8例患者室性期前收缩总数为0～80个/d,另外4例以夜间至清晨为主的频发室性期前收缩及短阵室性心动过速(其中1例伴有阵发性心房颤动;1例伴有频发房性期前收缩及房性心动过速,并且夜间心率缓慢29次/min伴交界性逸搏心律)。9例患者置入ICD后随访6～50个月,70次室颤发作中92.8%集中在22:00～07:00。12例患者均有晕厥病史,9例在住院期间发生室速/室颤,2例有猝死家族史,随访期间2例猝死。结论 Brs患者的室速/室颤发作多集中在夜间和凌晨;伴有房性心律失常和缓慢心律失常的Brs患者室速/室颤发生率更高。确诊的Brs患者发生心悸等不适时,应全面了解心律失常发生的情况,并酌情给予相应的治疗。     

Dual Chamber Implantable Cardioverter Defibrillator Benefits and Limitations

Dual chamber ICD capable of providing dual chamber pacing (DDD) and ventricular arrhythmia therapy is now available. We report our experience of clinical performance of dual chamber ICDs amongst Chinese population.Methods: 9 patients (6 men and 3 women) received dual chamber ICDs, mean age 50 ± 18.8 years. The indications were ventricular fibrillation (VF) [5], hemodynamic intolerant ventricular tachycardia (VT) [3] and unexplained syncope plus positive induction of VF [1]. The underlying cardiac pathology were congenital LQT syndrome(1), hypertrophic cardiomyopathy [2], coronary artery disease [2], rheumatic valvular disease [1], Brugada syndrome [1], arrhythmogenic right ventricular dysplasia [1] and idiopathic VF [1]. Four patients have documented paroxysmal atrial fibrillation (AF). All patients have defibrillation thresholds (DFT) determined with a binary search protocol starting at 12 joules (J) at implantation.Results: A total of 34 episodes of VF were induced at implantation with mean DFT 13.8 ± 7 J. The average shocking impedance was 40 ± 3.6 . The mean acute P wave measured 3.3 ± 1.3 mV and R wave measured 13.2 ± 3.2 mV. Atrial and ventricular thresholds, at pulse width 0.5 ms, averaged 0.8 ± 0.4 V and 0.4 ± 0.2 V. During follow-up period, 16 episodes of VF were documented and were successfully treated with the first programmed shock. In the patient with LQT syndrome, DDD was initiated to prevent pause-dependant VF. Three episodes of inappropriate therapy (15.8%) were delivered. One patient experienced 2 shocks after exercise. Stored electrograms showed sinus tachycardia with first degree heart block which was misdiagnosed as VT with retrograde 1:1 conduction. Another inappropriate therapy occurred with AF with fast ventricular response within the VF zone and VT therapy inhibitor was disabled.Conclusion: Dual chamber ICD allows combined benefits of DDD and VT/VF therapy. Storage of both atrial and ventricular electrograms provide more information in elucidation of nature of dysarrhythmias. Inappropriate shocks, though reduced, are still possible and the rigid algorithms of SVT discrimination from VT will need further published.     

Renal Sympathetic Denervation as an Adjunct to Catheter Ablation for the Treatment of Ventricular Electrical Storm in the Setting of Acute Myocardial Infarction

We present a case of ventricular storm (VS) in a patient with acute ST‐elevation myocardial infarction (STEMI). After initial successful thrombus extraction and percutaneous coronary intervention (PCI) of the proximal left anterior descending (LAD) coronary artery, a 63‐year‐old male patient showed recurrent monomorphic ventricular tachycardia (VT) and fibrillation (VF) episodes refractory to antiarrhythmic drug therapy. After initial successful VT ablation, fast VT and VF episodes remained an evident problem despite maximum antiarrhythmic drug therapy. Due to an increasing instability, renal sympathetic denervation (RDN) was performed. ICD interrogation and 24‐hour Holter monitoring excluded recurrent episodes of VT or VF at a 6‐month follow‐up (FU) after discharge. This case highlights that RDN was effective and safely performed in a hemodynamically unstable patient with VS after STEMI and adjunct catheter ablation. RDN may open a new avenue for an adjunctive interventional bailout treatment of such highly challenging patients.     

Analysis of implantable cardioverter defibrillator therapy in the Antiarrhythmics Versus Implantable Defibrillators (AVID) Trial

INTRODUCTION: The implantable cardioverter defibrillator (ICD) is commonly used to treat patients with documented sustained ventricular tachycardia (VT) or ventricular fibrillation (VF). Arrhythmia recurrence rates in these patients are high, but which patients will receive a therapy and the forms of arrhythmia recurrence (VT or VF) are poorly understood. METHODS AND RESULTS: The therapy delivered by the ICD was examined in 449 patients randomized to ICD therapy in the Antiarrhythmics Versus Implantable Defibrillators (AVID) Trial. Events triggering ICD shocks or antitachycardia pacing (ATP) were reviewed for arrhythmia diagnosis, clinical symptoms, activity at the onset of the arrhythmia, and appropriateness and results of therapy. Both shock and ATP therapies were frequent by 2 years, with 68% of patients receiving some therapy or having an arrhythmic death. An appropriate shock was delivered in 53% of patients, and ATP was delivered in 68% of patients who had ATP activated. The first arrhythmia treated in follow-up was diagnosed as VT (63%), VF (13%), supraventricular tachycardia (18%), unknown arrhythmia (3%), or due to ICD malfunction or inappropriate sensing (3%). Acceleration of an arrhythmia by the ICD occurred in 8% of patients who received any therapy. No physical activity consistently preceded arrhythmias, nor did any single clinical factor predict the symptoms of the arrhythmia. CONCLUSION: Delivery of ICD therapy in AVID patients was common, primarily due to VT. Inappropriate ICD therapy occurred frequently. Use of ICD therapy as a surrogate endpoint for death in clinical trials should be avoided.     

Gender differences in ventricular arrhythmia recurrence in patients with coronary artery disease and implantable cardioverter-defibrillators

OBJECTIVES: We sought to determine whether men and women with coronary artery disease (CAD) and implantable cardioverter-defibrillators (ICDs) differ in frequency of arrhythmia recurrence and whether gender differences are independent of clinical, electrocardiographic, and electrophysiologic characteristics. BACKGROUND: Epidemiologic studies show that women have a lower rate of sudden cardiac death (SCD) than men, even among patients with CAD. Whether this is due to differing susceptibilities to ischemia or to arrhythmia is unknown. METHODS: The clinical records and ICD data disks of 340 men and 59 women with CAD who received an ICD between June 1990 and June 2000 were reviewed. Ventricular tachycardia (VT) or ventricular fibrillation (VF) recurrences were compared between genders and relationship with other factors was analyzed. RESULTS: Sustained VT/VF occurred in 52% of men and 34% of women (p < 0.01). Men experienced more total VT/VF events (p < 0.01), more shock-treated VT/VF events (p < 0.03), more electrical storms (p < 0.001), and had VT/VF on more days in follow-up (p < 0.01). Gender differences were independent of measured clinical, electrocardiographic, and electrophysiologic factors. In stratified analyses, the gender differences in VT/VF recurrence were greatest in patients presenting with sustained monomorphic VT and those with inducible VT at electrophysiology study. CONCLUSIONS: Women were less likely to experience VT/VF, and had fewer VT/VF episodes, than men. These findings were strongest in patients with evidence of a stable anatomic VT circuit: those with clinical or electrophysiologically induced VT. This study suggests that differing susceptibility to arrhythmia triggering may underlie the known differences in SCD rates between men and women.     

埋藏式心脏复律除颤器在治疗恶性室性心律失常中的作用

评价埋藏式心脏复律除颤器 (ICD)在恶性室性心律失常治疗中所起的作用。 4例因反复发作室性心动过速 心室颤动 (VT VF)住院患者 ,采用ICD和药物治疗 ,并随访 2 1～ 36个月。结果 :4例患者均有室性心律失常再发 ,复发率 10 0 %。在复发心律失常时全部经ICD治疗成功转复窦性心律 ,有效率 10 0 %。对 4例ICD患者随访发现 ,共有 34次持续性VT VF发作 ,相对集中在 8个不同时间段 ,而每个时段都与患者全身状态改变有关。 2例非心律失常源性死亡。结论 :恶性室性心律失常患者有较高的复发率 ,且多数于再次发作时危及生命。服用抗心律失常药能减少VT VF发作 ,但不能完全控制其发作 ,尤其当患者处于各种应激状下时易反复发作。ICD治疗效果肯定 ,对这类高危患者能起到良好的保护作用 ,能有效减少心律失常源性死亡     

Measurement of ventricular electrogram amplitude during intraoperative induction of ventricular tachyarrhythmias.

Adequate sensing of ventricular tachycardia (VT) and ventricular fibrillation (VF) is necessary for proper functioning of an implantable cardioverter defibrillator (ICD). Several ICDs currently undergoing investigation have programmable fixed gain sensitivity for tachycardia detection. If intracardiac electrogram amplitude decreases below the programmed sensitivity during VT or VF, detection of a ventricular arrhythmia may be delayed or missed. The mean amplitude of intracardiac electrograms (ICEGM) recorded with bipolar epicardial or transvenous sensing leads was measured in 63 patients during induced VT and VF recorded in the operating room at the time of ICD implantation. The mean amplitude of the ICEGM during 41 episodes of VF in 15 patients decreased from 14.9 +/- 0.9 mV during sinus rhythm to 8.8 +/- 0.7 mV at 1 second, 9.7 +/- 0.7 mV at 5 seconds, and 9.4 +/- 0.7 mV at 10 seconds (p < 0.0001 vs sinus rhythm ICEGM) with endocardial leads. The mean amplitude of the ICEGM recorded during 173 episodes of VF in 43 patients with epicardial leads decreased from 10.4 +/- 0.3 mV in sinus rhythm to 7.8 +/- 0.3 mV at 1 second, 8.3 +/- 0.3 mV at 5 seconds and 8 mV at 10 seconds (p <0.0001 vs sinus rhythm ICEGM). The mean amplitude of epicardial and transvenous ICEGMs recorded during 34 episodes of monomorphic VT decreased from 18.5 +/- 1.8 mV (epicardial) and 14.4 +/- 2.0 mV (transvenous) during sinus rhythm (p = 0.15, epicardial vs transvenous) to 16.0 +/- 1.7 mV (epicardial) and 13.7 +/- 1.9 mV (transvenous) at 10 seconds (< 10% of baseline amplitude).(ABSTRACT TRUNCATED AT 250 WORDS)     

Syncope following cardioverter defibrillator implantation in patients with spontaneous syncopal monomorphic ventricular tachycardia.

AIMS: We sought to determine the incidence, mechanisms, and time to syncope recurrence in patients with spontaneous syncopal monomorphic ventricular tachycardia (SyMVT) treated with an implantable cardiac defibrillator (ICD). METHODS AND RESULTS: Incidence and causes of syncope following ICD implantation in consecutive patients (n=26) with spontaneous SyMVT were compared with those found in consecutive patients (n=50) with spontaneous non-syncopal monomorphic ventricular tachycardia (NSyMVT). Patients with SyMVT had a higher incidence of syncope (46% patients) than those with NSyMVT (2% patients) at 31+/-21 and 34+/-23 months follow-up, respectively (hazard ratio, 0.19; 95% confidence interval, 0.04-0.42; P=0.0001). Among the former, four patients (15%) had non-arrhythmic syncope and eight patients had arrhythmic syncope (31%), which was associated with either ICD proarrhythmia (seven episodes of VT acceleration or VF degeneration by ATP or low/high-energy shocks in three patients) or spontaneous VT and VF (five episodes in five patients). Median time to the first arrhythmic syncope was 376 days. Arrhythmic syncope presented after a first non-syncopal VT recurrence in six patients (75%). CONCLUSION: Syncope following ICD implantation is common in patients with SyMVT in contrast to patients with NSyMVT. Late syncope presentation supports reassessment of driving restrictions in this setting.     

Ablation of a catecholaminergic polymorphic VT and VF originating from Purkinje fibers--a case report

We describe a case of a 25-year-old woman suffering from recurrent adrenergic polymorphic ventricular tachycardia (PVT). As a 14-year-old the patient suffered from recurrent episodes of syncope during exercise or emotion. On Holter monitoring unsustained runs of PVT were observed. The patient survived SCD (VF) which occurred near the hospital. An ICD was implanted and during the first year over 150 adequate discharges were present. During 9 year follow-up the patient had to have 4 ICDs replaced. She suffered from post-traumatic stress disorder syndrome due to frequent ICD shocks. After age of 23 she was admitted to our hospital and an ablation using the CARTO system was performed. No low voltage areas were observed. During the study ventricular premature beats and VT/PVT runs were observed originating from the Purkinje fibres. RF applications were delivered at those sites, during which abrupt PVT runs were present. After the ablation no ventricular arrhythmia was registered in the ICD memory during 2-year follow-up.     

置入型心律转复除颤器52例术中除颤阈值的测定及术后随访

目的 探讨置入型心律转复除颤器(ICD)置入术中除颤阈值(DFT)的测定方法并观察术后随访结果.方法 52例置入ICD患者,其中单腔ICD 25例(48.08%),双腔ICD 23例(44.23%),三腔ICD 4例(7.69%).置入术中用测定除颤安全范围(DSM)方法进行DFT测定,并对患者进行定期随访.结果 52例ICD置入术中,测得DFT为(13.27±2.95)J,DSM为(17.40±2.89)J,手术中无严重并发症发生.52例中,38例出现恶性室性心律失常,其中469次为非持续性(可自行终止)室性心动过速(VT),持续性VT发作265次;经抗心动过速起搏治疗1阵转复成功245次(92.45%),2阵转复成功13次(4.91%),抗心动过速起搏治疗转复未成功经电转复7次(2.64%),均经低能量电转复成功.心室颤动(VF)发作141次均成功识别,其中14次在释放治疗前VF自行终止.127次VF经电除颤治疗,经电除颤治疗1次成功116次(91.34%),除颤能量为(12.84±3.18)J,2次成功11次(8.66%),除颤能量为(16.36±2.34)J.结论 应用DSM测定进行ICD置入术中DFT测定安全可行.     

右室流出道心律失常的发作方式与单导管消融治疗

报道 33例右室流出道心律失常的发作方式与单导管消融治疗。 3例仅室性早搏 (简称室早 )发作 ,30例室早与室性心动过速 (简称室速 )或心室颤动 (简称室颤 )并存。其中室早合并短阵单形室速 17例 ,合并持续单形室速 6例 ,合并多形室速 4例 ,合并快速室速或心室扑动 2例 ,合并室颤 1例。单点穿刺股静脉后 ,行右房或心室造影 ,将单根多枚电极导管按需放置于右室心尖部或流出道 ,行电生理检查、起搏与激动顺序标测和消融治疗。结果 :消融成功 30例 ,成功率 91%。靶点电图较体表QRS波始点早 38± 12 .4ms。 12例成功靶点位于右室流出道游离壁、9例位于间隔部、5例在游离壁和间隔部作多点片状消融、3例位于肺动脉瓣上、1例在右室流出道间隔部和左室间隔部消融成功。操作时间 5 2± 2 2 .2min ,X线透照时间 2 6± 18.0min ,放电时间 373± 111.7s。术中 1例未诱发心律失常 ,未行消融。 3例发生并发症 ,2例终止消融。 1例右室流出道穿孔 ,心包压塞。 1例多形室速 ,消融中室早多次触发室颤。 1例剧烈胸痛 ,冠状动脉造影示前降支近端 5 0 %局限狭窄。随访 14± 4 .5个月 ,无死亡病例 ,3例复发 ,1例消融 3次均复发 ,复发率 10 %。住院总花费人均 9133± 12 0 0元。结论 :右室流出道心律失常发病形式多种多样 ,单导?     

无痛治疗在植入型心律转复除颤器患者心脏性猝死一级和二级预防中的应用

目的 随访植入型心律转复除颤器(ICD)患者,了解抗心动过速起搏(antitachycardia pacing,ATP)作为室性心动过速(VT)无痛治疗手段在心脏性猝死一级和二级预防中的应用.方法 对2005年1月至2009年6月符合ICD一级和二级预防标准并在我院植入ICD的患者进行随访.将ICD的诊断程序设置为VT...     

双腔埋藏式心脏复律除颤器

双腔埋藏式心脏复律除颤器 (ICD)可提供起搏及抗室性和房性心律失常的治疗。报道 11例双腔ICD应用的临床体会。男 8例、女 3例 ,年龄 6 0 .5 5± 10 .0 7岁。缺血性心脏病 9例、Brugada综合征 1例、缺血性心脏病合并肥厚型梗阻性心脏病 1例。双腔ICD安置指征有 :室上性快速心律失常伴室性快速心律失常 6例 ,室性快速性心律失常伴房室阻滞 1例、伴左室功能不全 4例 ;临床上明确记录到室性心动过速 (简称室速 )、心室颤动 (简称室颤 )和室上性快速心律失常者分别为 8,2和 5例。 8例病人术前进行电生理检查 ,诱发出持续性室速 6例、室颤 2例 ;3例行电生理检查 ,其中 2例太虚弱、1例为反复发作持续性室速。 5例安置具有心室转复除颤伴心房、心室起搏的ICD ,5例安置具有心房、心室起搏转复及除颤的ICD ,1例安置具有双心室起搏及心室转复、除颤的ICD。所有病人在置入ICD时都进行除颤阈值的测定。总共有 2 3次室颤被诱发 ,除颤阈值为 12 .0 9± 5 .2 4J,除颤电极阻抗为 44 .0 0±11.0 5Ω ,P波和R波电压幅度分别为 3.5 3± 1.32mV ,13.42± 4.73mV ,心房、心室起搏阈值分别为 1.39± 0 .71和 0 .91± 0 .38V。随访 8.82± 5 .0 0 (2～ 19)个月 ,5例共有 12 0次持续性室速发生 ,其中 118次经抗心动过速起搏成功?