Selected patients listed for cardiac transplantation may benefit from defibrillator implantation regardless of an established indication.

BACKGROUND: End-stage heart failure (HF) patients are at high risk of sudden cardiac death. This study evaluates the role of implantable cardiac defibrillators (ICDs) in HF patients awaiting cardiac transplantation. METHODS: We identified 194 consecutive patients (age 51 +/- 12 years) with New York Heart Association Class 3 or 4 HF (ejection fraction 22 +/- 9%) listed for cardiac transplantation, 35 of whom underwent ICD implantation. Of the implanted patients, 16 (Group A) had an established indication for ICD implantation (cardiac arrest, n = 10; sustained ventricular tachycardia [VT], n = 3; and positive electrophysiology study, n = 3). Nineteen patients (Group B) underwent ICD implantation for non-established indications (syncope with non-ischemic cardiomyopathy, n = 4; non-sustained VT, n = 15). There were no procedural complications from ICD implantation. RESULTS: During follow-up of 9.2 +/- 10.1 months, there were 3 deaths in the ICD groups (A and B), and 40 in the control group (8.6% vs 25.2%, p = 0.032). Five patients in Group A and 6 in Group B (31%) received appropriate ICD therapy. The number of therapies per patient and the time to the first shock were similar between Groups A and B. Four of 6 Group B patients on outpatient inotropic therapy (67%) received appropriate ICD therapy. CONCLUSIONS: Selected end-stage heart failure patients awaiting heart transplantation, including those without established ICD indications, are at high risk for malignant arrhythmias and may benefit from ICD implantation. Patients with ICD seem to have improved survival compared to those without ICD. Randomized prospective studies are needed to confirm these findings.     

Anesthésie et défibrillateur automatique implantable

Since the introduction of first generation automatic implantable cardioverter defibrillators (AICD) in 1980, an increasing number of such devices have been inserted in patients at high risk for sudden death by ventricular tachycardia or fibrillation (VT/VF). With the improvement of technology and implanting techniques, devices may be inserted at present subcutaneously into the abdominal or the thoracic wall, rather than by thoracotomy. The anaesthesist is involved in the primary implantation of the AICD and the secondary testing of efficiency. Implantation generally requires general anaesthesia and the extension of monitoring is guided by the patient's underlying disease(s). The efficiency of the implanted system is tested one to two months later in inducing VT/VF under general anaesthesia and in determining the defibrillation threshold.The anaesthetist may also have to take care of patients with a AICD. For such cases the following recommendations can be made: a) gloves shoud be worn by doctors and nurses coming into contact with these patients, in order to limit the risk of electrification; b) a ring magnet must be available to inactivate the unit; c) in case of external defibrillation, the external paddles should be oriented perpendicularly to the line joining the two implanted electrodes; d) AICD should be disabled during electrocautery and prior to electroconvulsive therapy; e) the assistance of a electrophysiologist may be helpful for the management of these patients.     

Treatment of malignant ventricular arrhythmias with the automatic implantable cardioverter defibrillator.

Twenty-eight patients with malignant ventricular arrhythmias were treated with the automatic implantable cardioverter-defibrillator (AICD) in a 14-month period. Thirteen patients were resuscitated from a ventricular fibrillation (VF) episode. Fifteen patients presented with ventricular tachycardia (VT) refractory to medical therapy. The etiology was coronary artery disease in 23 of 28 patients (82%), dilated cardiomyopathy in 2 of 28 patients (7%), sarcoidosis in 2 of 28 patients, and 1 patient in 28 had lupus erythmatosis. The mean left ventricular ejection fraction was 29%. A total of 27 of 28 patients (96%) patients had inducible ventricular tachycardia using programmed stimulation. The patients considered for AICD implant failed a mean of 3.6 antiarrhythmic drugs. Rate counting and defibrillating leads were inserted through a lateral thoracotomy in 17 patients and a mediansternotomy incision in 11 patients in conjunction with another cardiac procedure in 10 patients. The generators were positioned in a subcutaneous pocket beneath the left costal margin. There were no operative deaths. The mean follow-up was 6.7 months (range 1 to 14) with no VT/VF deaths in patients with defibrillators. The study demonstrated that AICD is an effective device for prevention of sudden cardiac death.     

Strategies in the surgical treatment of malignant ventricular arrhythmias. An 8-year experience.

Introduction of the automatic implantable cardioverter defibrillator (AICD) has dramatically affected the surgical treatment of malignant ventricular tachyarrhythmias. The authors continue to perform electrophysiologically directed subendocardial resection (SER) of left ventricular (LV) scars in selected patients, and we revascularize (CABG) those patients undergoing AICD implantation who have significant myocardial ischemia. In an attempt to define the optimal role of each procedure, this report analyzes our 8-year experience with 348 consecutive patients treated surgically for these arrhythmias (SER since 1983 and AICD since 1986). All patients undergoing SER had organized ventricular tachycardia (VT) as a result of myocardial infarction, and most had LV aneurysms; of those undergoing AICD or AICD/CABG, 60% had VT, 15% had ventricular fibrillation, and 25% had both or were noninducible. The thirty-day mortality rate was 1.5% (3/197) for AICD, 5.4% (5/93) for AICD/CABG, and 8.6% (5/58) for SER; these mortality figures are not significant different. Late deaths in all groups were predominantly due to congestive heart failure, and actuarial survival as well as freedom from sudden death was similar between the groups at 4 years. Recurrent VT occurred in 167 of 282 (59%) of long-term survivors of AICD or AICD/CABG during follow-up and in nine of 53 (17%) of those with SER. Forty-eight per cent of survivors of AICD or AICD/CABG required antiarrhythmic medications, whereas only 11% of those with SER required antiarrhythmics. Long-term survival in each group is much higher than that reported for comparable patients with severe LV dysfunction treated medically. In those patients with organized VT and LV aneurysm who are judged able to survive the procedure, SER offers a high likelihood of cure rather than simple prevention of sudden death.     

The automatic implantable cardioverter defibrillator--clinical experience in patients with life-threatening ventricular tachyarrhythmias

Five patients (pts) with life-threatening ventricular tachyarrhythmias (idiopathic VF; 2 pts, Torsade de pointest; 1 pt, VT/VF after valve replacement; 2 pts) underwent surgical treatment of the automatic implantable cardioverter defibrillator (AICD). Implantation of an AICD was indicated for patients who survived circulatory arrest due to documented VT and/or VF. The patient should be medically refractory or medical treatment precluded by hemodynamic instability; other surgical treatment should not be possible. We selected myocardial electrode for sensing and small and large patch electrodes for defibrillating. VF/VT was induced 1 to 6 times for the measurement of defibrillation threshold (DFT). In all of our pts, the AICD appropriately discharged at postoperative EPS. In three of pts, the AICD discharged within the postoperative hospital phase, in two because of sinus tachycardia during treadmill test and restored sinus rhythm after non-sustained VT. As for complications, in one pt. with severe LV dysfunction, incessant form of VT/VF occurred after DFT testing and LV assist circulation and IABP were needed. In two pts, inappropriate discharge and in two, pericarditis were recognized postoperatively. It was considered that this system was effective for the treatment of life-threatening ventricular tachyarrhythmias but strict indication was necessary because of unsolved problems.     

Impending sudden cardiac death: treatment with myocardial revascularization and the automatic implantable cardioverter defibrillator

Myocardial revascularization and implantation of the automatic implantable cardioverter defibrillator (AICD) have individually been shown to improve survival in patients after sudden cardiac death. Their combined role has not been well defined. Twenty-three survivors of sudden death underwent revascularization and AICD implantation at an average age of 59 years. The initial arrest was caused by ventricular fibrillation in 15 and ventricular tachycardia in 8. Exercise stress tests, ambulatory ECGs, and electrophysiological monitoring with programmed electrical stimulation were done preoperatively and postoperatively. Follow-up averaged 24 months with a two-year survival of 91%. Eight patients (35%) required AICD resuscitation an average of 8 months postoperatively, and electrophysiological testing did not accurately predict arrhythmia recurrence. The addition of AICD implantation to revascularization substantially improves survival of patients with sudden cardiac death.     

A case of idiopathic ventricular tachycardia with ventricular fibrillation successfully treated with cryoablations and implantable cardioverter defibrillator]

A 16-year-old girl with medically refractory idiopathic ventricular tachycardia (VT) with ventricular fibrillation (VF) underwent cryoablations of the VT origin and received implantable cardioverter defibrillator (ICD). Intraoperative epicardial and endocardial mapping demonstrated the earliest activation site of VT in the infundibular septum of right ventricle. Cryoablations were applied through a pulmonary arteriotomy under mild hypothermic cardiopulmonary bypass with the heart beating. Because of the episodes of VF. ICD implantation was followed. Her postoperative course was uneventful and she remains free from VT and VF.     

Sudden death and tailored medical therapy in elective candidates for heart transplantation.

BACKGROUND: Due to the shortage of donor organs there is a long waiting time for heart transplantation. As a consequence, a high mortality rate on the waiting list diminishes the potential benefit of the procedure. Tailored medical therapy optimized according to the individual patients demands was introduced to select responding HTx candidates for continued management without transplantation. The development of modes of death over time (heart failure, sudden arrhythmic) in this population is unknown. METHODS: In 434 elective candidates for heart transplantation, submitted to our institution in the years 1984-1997 (50% coronary artery disease, mean age 51.6 +/- 12 years, 86% males) medical therapy was adjusted according to the results of repeated right heart catherizations. Adjuncts to conventional therapy with ACE inhibitors, digitalis and diuretics were amiodarone, beta-blockers, spironolactone, oral anticogulants, molsidomine or nitrates. Only patients not responding to these measures were processed to HTx. Clinical events (death, mode of death, HTx, resuscitation) were noted and analyzed by the Kaplan-Meier method and related to patients characteristics by multivariance analysis. RESULTS: During the mean follow-up of 2.36 +/- 2.4 years only 113 patients (25%) received a donor heart. One hundred-sixteen patients (26%) died without transplantation. Eighty-three (72%) of the deaths were sudden, 24 (20%) due to progression of heart failure and 9 (8%) due to other reasons. A shift from heart failure to sudden death was observed. Including 8 successful resuscitations due to documented VT/VF, there is a 20% risk of having a major arrhythmic event during the first two years of observation. Long-term (>1 year) medical responders had better hemodynamics at entry. Patients who died suddenly had similar clinical and hemodynamic data at entry than patients who needed an early transplant, but were in a comparable NYHA stage before death than long-term medical responders (2.15 +/- 0.8 vs 1.82 +/- 0.6, NS). Patients dying suddenly had significant more ventricular premature beats (1.6 +/- 2.9%/24 hours vs 1.06 +/- 2.8%/24 hours, p < .01) and complex ventricular arrhythmias (7.3 +/- 2.7/24 hours vs 1.98 +/- 5.6/24 hours, p < .01) than long-term responders. Seventy-five percent of all sudden death occurred during the first 2 observation years. CONCLUSIONS: The rate of heart failure death in elective candidates for heart transplantation under optimized medical therapy is low when patients are followed closely and transplant can be done rapidly after deterioration is recognized. Sudden death represents the highest risk for most patients. This event occurred predominantly in stable patients under tailored medical therapy without indication for HTx at that time. Our results strongly demand strategies for risk stratification and the investigation of prophylactic measures in this population.     

Surgical versus nonsurgical therapy of fatal tachyarrhythmias]

Interventional treatment is necessary for fatal drug-refractory tachyarrhythmias. Thirty-three, 33 and 16 patients (pts) with intractable ventricular tachycardia (VT) and/or fibrillation (VF) were managed with cryosurgery (CS), electrical catheter ablation (EA) and implantable pacer-cardioverter-defibrillator (PCD), respectively. Seventy-six and 43 pts with sudden death risk in the Wolff-Parkinson-White syndrome (WPW) also underwent CS and EA, respectively. CS success rates were 85% in VT/VF and 95% in WPW. Those of EA were 48% and 81%, respectively. EA success rates were 100% (6/6) in idiopathic verapamil-sensitive VT originated from LV, 0% (0/2) in VT following TOF repair and 0% (0/2) in idiopathic VT originated from right ventricular outflow tract. A new VT developed in 5 of 11 pts with arrhythmogenic right ventricular dysplasia (ARVD) following EA. PCD was effective for prevention from sudden death in idiopathic VF and pleomorphic VT. All of pharmacologic, EA and CS therapies were relatively effective in ischemic heart disease without low EF. In conclusion, the decision of VT-VF therapy may be affected by the underlying heart disease and EA may be established as an initial intervention for high risk WPW.     

Operative therapy of malignant ventricular rhythm disturbances

Pre- and postoperative electrophysiologic study (EPS), intraoperative cardiac mapping, and extended endocardial resection of scar (EER) has enabled us to identify subgroups among 94 patients who have had operation to control or prevent malignant ventricular arrhythmia. Operative mortality was 8.5% and cure or prevention of ventricular arrhythmia was accomplished in 92% of survivors. Group 1: 13 patients were resuscitated from "sudden death" due to ventricular fibrillation (VF). All had exercise-induced VF and/or ventricular tachycardia (VT). Preoperative EPS revealed no inducible VT/VF. All had coronary artery disease, without evidence of myocardial infarction (MI) or ventricular wall motion abnormality; all were cured with conventional myocardial revascularization. Group 2: 65 patients had MI with residual left ventricular wall motion abnormality, usually aneurysm. The malignant arrhythmia, either sustained VT (38 patients) or VF (27 patients), was inducible by EPS but not usually by exercise, and all were refractory to medical therapy. Treatment was operative mapping, aneurysmectomy, EER, and coronary revascularization. Operative mortality was 11.9%; 90% of survivors are arrhythmia free, off drugs; 10% are now drug responsive. Group 3: 3 patients without coronary disease had VT or VF caused by endocardial sarcoidosis or operative scar from a previous congenital heart operation. Treatment was EPS, operative mapping, and excision of abnormal endocardial scar with no operative mortality. Group 4: 13 patients underwent aneurysmectomy for indication other than arrhythmia, but had preoperative ventricular irritability which was not life-threatening. Operation was aneurysmectomy, prophylactic EER, and revascularization with no mortality and no postoperative arrhythmic events. After many years of unpredictable and unsatisfactory results from various empirical surgical approaches, the operative treatment of malignant ventricular arrhythmia is now based on sound electrophysiologic principles.     

Automatic implantable cardioverter-defibrillator: techniques of implantation and results

An initial experience with use of the automatic implantable cardioverter-defibrillator (AICD) is described. Twelve patients received the device. One death has occurred during a mean follow-up of 15 months, and it was due to causes other than arrhythmias. Appropriate device discharge terminating a malignant arrhythmia occurred in 9 patients (75%). The observed survival (92%) far exceeds that to be expected in survivors of sudden death treated by conventional means. There have been no operative deaths. Morbidity has been minimal, although three reoperations were required in 2 patients because of lead dislodgment. The AICD has been demonstrated to be effective in treating patients at risk for sudden arrhythmic death. It can be employed safely with minimum morbidity using a variety of implantation techniques.     

Time to first pulse after automatic implantable cardioverter defibrillator implantation.

Should automatic implantable cardioverter defibrillator (AICD) power sources be explanted and discontinued if they have not pulsed during the first generator life? We have followed 59 patients an average of 23 months (range, 3 days to 8.4 years) after AICD implantation. The indication for AICD implantation was based on clinical dysrhythmia, history of sudden death, and findings at electrophysiologic study. Thirty-eight of 59 patients (64%) had experienced sudden death and 52/58 (90%) were inducible at electrophysiologic study. Excluding 5 inappropriate pulsing episodes, 31 of 59 patients (53%) had 235 pulses (range, 1 to 36; median, 2 pulses). The time to first pulse after implantation ranged from 1 day to 3.5 years with a median time of 2 months. In 6 patients, the first pulsing occurred later than 1 year after AICD implantation. Fifteen generators demonstrating impending power source failure have been replaced in 11 patients. Power source depletion occurred at an average of 24.1 months (range, 8 to 40 months). In 3 patients, the first pulsing occurred after generator depletion and replacement. By univariate analysis, none of 13 variables (sex, age, cardiac disease process, functional class, previous myocardial infarction, sudden death history, ejection fraction, type of dysrhythmia, inducibility with electrophysiologic testing, number of extra stimuli required for induction, left ventricular aneurysm resection, endocardial resection, or concomitant operation) was found to be a predictor of pulsing (p greater than 0.05). We conclude that the majority of patients with pulses after AICD implantation will have them during the first 6 months.(ABSTRACT TRUNCATED AT 250 WORDS)     

Long-term surgical results in sudden death syndrome associated with cardiac dysfunction after myocardial infarction.

To evaluate the surgical results in patients with inducible ventricular tachyarrhythmias due to coronary disease and left ventricular dysfunction, the authors reviewed their experience in 170 patients who had survived one or more cardiac arrests after myocardial infarction and were unresponsive to drug therapy based on electrophysiologic studies (EPS). There were nine operative deaths (5%). Based on intraoperative EPS, surgical remodeling of left ventricular dysfunction (aneurysm resection, infarct debulking, and septal reinforcement) with map-guided cryoablation and coronary artery bypass graft was performed in 34 patients (group A), and left ventricular remodeling and coronary artery bypass graft without guided endocardial resection was performed in 25 patients (group B). Forty-three patients (group C) had coronary artery bypass graft with implantation of an automatic implantable cardioverter defibrillator (AICD). Group D (68 patients) received AICD only. After operation, based on EPS results, four patients in group A (12%) and three patients in Group B (15%) required AICD implantation. Overall survival at 6 years was 65%, 48%, 85%, and 58% in patient groups A, B, C, and D, respectively (p = not significant). During follow-up in group A patients, none died suddenly and none needed AICD. In group B, two patients required AICD 3 and 5 years later, and five patients died suddenly. The incidence of sudden death was 2.3%/patient/year and 3.5%/patient/year after AICD implantation (groups C and D). At 6 years, cardiac-event-free survival was 80% and 70% for groups A and B and 38% and 24% for groups C and D, respectively (p less than 0.001). Patients receiving map-guided ablative procedures had significantly improved cardiac-event-free survival rates.     

Surgical management of sustained ventricular arrhythmias presenting within eight weeks of acute myocardial infarction

When it occurs after a recent (less than eight weeks) myocardial infarction, sustained ventricular tachycardia (VT) or fibrillation (VF) has resulted in a high one-year mortality despite antiarrhythmic drug therapy. We have operated on 29 patients with this syndrome either on an emergency basis because they had medically refractory VT or VF (19 patients) or electively if they had persistent congestive heart failure or angina and VT or VF (10 patients). Ages ranged from 36 to 82 years (mean, 60 years), and the mean left ventricular ejection fraction was 31 +/- 13%. Each patient had failed a trial of one or more (average, four) antiarrhythmic drugs and because of VT, required electrical cardioversion on an average of five occasions. Intraoperative mapping was complicated by multiple VT morphologies (9 patients), the rapid degeneration of VT to VF (5 patients), and the inability to induce VT reliably (5 patients). Subendocardial excision was performed at the site of the earliest electrical activity, or if no single site could be identified, a wide subendocardial excision of all visible scar was performed. There were 4 perioperative deaths (14%). All operative survivors underwent postoperative electrophysiological studies. Twenty of them required no further antiarrhythmic therapy, but 5 patients required drug therapy because of either spontaneous (2 patients) or electrically induced (3 patients) VT. During follow-up (average, 16 months) of these 25 patients, there have been 3 late deaths, 2 of them sudden. Two of the 3 late deaths were those of patients taking antiarrhythmic drugs. Our results demonstrate the effectiveness of early operative intervention when sustained ventricular arrhythmias complicate recovery after myocardial infarction.(ABSTRACT TRUNCATED AT 250 WORDS)     

Outpatient dobutamine for refractory congestive heart failure: advantages, techniques, and results.

Patients with refractory, end-stage congestive heart failure awaiting heart transplantation may be treated efficaciously with intermittent infusions of dobutamine given on an outpatient basis. The treatment appears to be well tolerated. Nevertheless, careful attention to electrolyte balance and arrhythmia control is essential to minimize the risk of sudden death. Use of a tunneled subcutaneous catheter essentially eliminates the risk of infection associated with this type of delivery system. Patients who have worsening heart failure while receiving dobutamine as outpatients should be fitted for a mechanical assist device before complications develop that may contraindicate transplantation.     

B‐Type Natriuretic Peptide Levels Predict Ventricular Arrhythmia Post Left Ventricular Assist Device Implantation

B‐type natriuretic peptide (BNP) levels have been shown to predict ventricular arrhythmia (VA) and sudden death in patients with heart failure. We sought to determine whether BNP levels before left ventricular assist device (LVAD) implantation can predict VA post LVAD implantation in advanced heart failure patients. We conducted a retrospective study consisting of patients who underwent LVAD implantation in our institution during the period of May 2009–March 2013. The study was limited to patients receiving a HeartMate II or HeartWare LVAD. Acute myocardial infarction patients were excluded. We compared between the patients who developed VA within 15 days post LVAD implantation to the patients without VA. A total of 85 patients underwent LVAD implantation during the study period. Eleven patients were excluded (five acute MI, four without BNP measurements, and two discharged earlier than 13 days post LVAD implantation). The incidence of VA was 31%, with 91% ventricular tachycardia (VT) and 9% ventricular fibrillation. BNP remained the single most powerful predictor of VA even after adjustment for other borderline significant factors in a multivariate logistic regression model (P < 0.05). BNP levels are a strong predictor of VA post LVAD implantation, surpassing previously described risk factors such as age and VT in the past.     

Indications for different modes of surgical therapy in medically refractory ventricular arrhythmias

Fifty-one adult patients were referred for surgical treatment during the time period from July 1980 to November 1985. The average age was 59 +/- 6 years (19-70 years). All patients had symptomatic ventricular tachycardia that was refractory to standard or experimental drug therapy. On the basis of patient condition, site of arrhythmia, ventricular function, and extent of coronary disease, 21 patients were classed as good risk (GR) while 30 patients were thought to represent a poor surgical risk (PR). Thirty-two patients (15 GR, 17 PR) underwent electrophysiologic guided endocardial resection of arrhythmic foci. The hospital mortality was 12% (4/32), and two additional patients died late. All deaths were in poor risk patients. Recurrent arrhythmia was the primary cause of death in only one patient. Nineteen patients have required automatic internal cardioverter defibrillation (AICD) or chronic burst pacing (BP) with an implantable radiofrequency stimulator, with no operative mortality. AICD implantation was chosen for 13 drug refractory patients who were either poor surgical risk and/or had a tachycardia rate above 130 beats/minute with multiple scars or a multifocal tachycardia. Six additional patients who had tachycardia less than 130 beats/minute and whose arrhythmia could be safely terminated with BP had radiofrequency stimulator implantation. The one late death in this group was in a medically noncompliant patient. On the basis of this experience, we feel that map-guided endocardial resection should be offered to all good risk patients with a single scar and unifocal tachycardia who are refractory to medical treatment. This operation should be considered in all patients who have frequent, life-threatening attacks of tachycardia of any sort on maximum drug therapy. The remainder can be well managed with an AICD if their tachycardia rate is greater than 130 beats/minute or with BP using a radiofrequency stimulator.     

Continuing experience with the automatic implantable cardioverter defibrillator.

The automatic implantable cardioverter defibrillator (AICD) is now used commonly in the management of malignant ventricular arrhythmias. Its use may obviate the need for antiarrhythmic drugs or endocardial resection. We reviewed our continuing experience with the AICD to determine its safety and efficacy. Since June 1987, 102 patients (mean age: 63 years) who survived out-of-hospital ventricular fibrillation or hemodynamically unstable ventricular tachycardia not associated with acute myocardial infarction underwent implantation of an AICD. There were three operative deaths and nine complications. Eighty-nine patients are alive. No patient has experienced sudden cardiac death. Forty-two patients (43%) have had 1 or more AICD discharges associated with symptoms of cardiac arrest. During AICD implantation, it appears preferable to configure lead placement by individual patient characteristics rather than by a rigid protocol. The relative safety and efficacy of the AICD support its use as an alternative to toxic medications or more dangerous endocardial resection in suboptimal candidates.     

Treatment for perioperative arrhythmias with nifekalant hydrochloride

Ventricular tachycardia (VT), ventricular fibrillation (VF), and atrial flutter (AFL) are potentially fatal or serious complications arising after cardiac surgery. Generally, we treat these complications with class I antiarrhythmic agents and/or direct counter shock (DC). However, sometimes these complications do not respond to antiarrhythmic agents and require frequent DC. Moreover, these class I agents induce heart failure due to their negative inotropic effect. Nifekalant hydrochloride (NIF) is a class III antiarrhythmic agent that prolongs the refractory period of the atrial and ventricular myocardium without any negative inotropic action. From July 2003 to September 2004, we treated 11 patients with NIF for perioperative arrhythmias (VT 5, VF 2, and AFL 4). NIF was administered by continuous intravenous infusion (0.3 to 0.4 mg/ kg/h) to prevent the recurrence of VT/VF and AFL. NIF prevented the recurrence of VT in 3 of the 5 cases. No recurrence was observed in 2 cases with VF. Furthermore, NIF prevented the recurrence of AFL in all the 4 patients. None of the patients exhibited changes in heart rate, cardiac output, and QTc interval. Additionally, no occurrence of Torsades de pointes was observed in any of the cases. In conclusion, NIF is an effective and safe antiarrhythmic agent for the treatment of perioperative arrhythmias under continuous monitoring of the QTc interval.