Inappropriate Sinus Tachycardia Research Articles

Stellate ganglion block: A therapeutic alternative for patients with medically refractory inappropriate sinus tachycardia?

Inappropriate sinus tachycardia (IST) is a clinical syndrome characterized by presence of non-paroxysmal tachyarrhythmia manifesting with increased resting heart rate and exaggerated or persistent response to exercise or position. When IST is intolerable and medically refractory, invasive therapies such as sinus node modification or atrioventricular node ablation with placement of permanent pacemaker are tried to control symptoms. We present a 34 year old patient with symptomatic IST unresponsive to medical therapy who underwent anesthetic block of the right and left stellate ganglia. At four month follow up the patient demonstrated sustained improvement in heart rate and reported freedom from previous symptoms.

Use of Ivabradine in a Patient Having Pacemaker and Inappropriate Sinus Tachycardia

Use of Ivabradine in a Patient Having Pacemaker and Inappropriate Sinus Tachycardia

Transthoracic Epicardial Catheter Ablation

Transthoracic epicardial catheter ablation is a useful supplemental or even preferred strategy to eliminate cardiac arrhythmias in the electrophysiology laboratory. The indication for this technique has extended to a diverse range of cardiac arrhythmias, including scar-related ventricular tachycardia (VT), idiopathic VTs, accessory pathways, atrial tachycardias, inappropriate sinus tachycardia, and atrial fibrillation, as the epicardial substrates of these tachyarrhythmias have become increasingly recognized. When endocardial ablation and epicardial ablation through the cardiac veins are unsuccessful, transthoracic epicardial ablation should be the next option. Intrapericardial access is usually obtained through a subxiphoidal pericardial puncture. This approach might not be possible in patients with pericardial adhesions caused by prior cardiac surgery or pericarditis. In such cases, a hybrid procedure involving surgical access with a subxiphoid pericardial window and limited anterior or lateral thoracotomy might be a feasible and safe method of performing epicardial catheter ablation in the electrophysiology laboratory. Potential complications associated with this technique include bleeding and collateral damage to the coronary artery and phrenic nerve. Although the risk of these complications is low, electrophysiologists who attempt epicardial catheter ablation should know the complications associated with this technique, how to minimize their occurrence, and how to rapidly recognize and treat the complications that they encounter. This review discusses the indications, techniques, and complications of transthoracic epicardial catheter ablation.

Inappropriate Sinus Tachycardia

Inappropriate sinus tachycardia (IST) is a syndrome in which the sinus heart rate is inexplicably faster than expected and associated symptoms are present. The heart rate at rest, even in a supine position, can exceed 100 beats/min; minimal activity accelerates the rate rapidly and substantially. Patients with IST may require restriction from physical activity. Mechanisms responsible for IST are understood incompletely. It is important to distinguish IST from so-called appropriate sinus tachycardia and from postural orthostatic tachycardia syndrome, with which overlap may occur. Because the long-term outcome seems to be benign, treatment may be unnecessary or may be as simple as physical training. However, for patients with intolerable symptoms, therapeutic measures are warranted. Even at high doses, β-adrenergic blockers, the first-line therapy, often are ineffective; the same is true for most other medical therapies. In rare instances, catheter- or surgically- based right atrial or sinus node modification may be helpful, but even this is fraught with limited efficacy and potential complications. Overtreatment, in an attempt to reduce symptoms, can be difficult to avoid, but is discouraged.

Atrial tachycardia provoked in the presence of activating autoantibodies to β2-adrenergic receptor in the rabbit

A recent clinical study of patients with inappropriate sinus tachycardia reported that autoantibodies to β-adrenergic receptors (β2ARs) could act as agonists to induce atrial arrhythmias. To test the hypothesis that activating autoantibodies to the β2AR in the rabbit atrium are arrhythmogenic. Five New Zealand white rabbits were immunized with a β2AR second extracellular loop peptide to raise β2AR antibody titers. A catheter-based electrophysiologic study was performed on anesthetized rabbits before and after immunization. Arrhythmia occurrence was determined in response to burst pacing before and after the infusion of acetylcholine in incremental concentrations of 10 μM, 100 μM, and 1 mM at 1 mL/min. In the preimmune studies when β2AR antibody titers were undetectable, of a total of 20 events, only 3 episodes of nonsustained (<10 seconds) atrial arrhythmias were induced. In the postimmune studies when β2AR antibody titers ranged from 1:160,000 to 1:1.28 million, burst pacing induced 10 episodes of nonsustained or sustained (≥10 seconds) arrhythmias in 20 events (P = .04 vs preimmune; χ(2) and Fisher exact test). Taking into account only the sustained arrhythmias, there were 6 episodes in 20 events in the postimmune studies compared with 0 episodes in 20 events in the preimmune studies (P = .02). Immunized rabbits demonstrated immunoglobulin G deposition in the atria, and their sera induced significant activation of β2AR in transfected cells in vitro compared to the preimmune sera. Enhanced autoantibody activation of β2AR in the rabbit atrium leads to atrial arrhythmias mainly in the form of sustained atrial tachycardia.

Supraventricular Tachycardia

Supraventricular tachycardias (SVTs) comprise a group of arrhythmias for which the atria and/or atrioventricular (AV) node are integral to sustaining the rhythm. These arrhythmias typically have a benign natural history but account for a considerable proportion of patients presenting with symptoms including palpitations, shortness of breath, chest discomfort, dizziness, and, on occasion, syncope. They affect a broad range of patients, from young, otherwise healthy adults and children to elderly patients with multiple comorbidities. Although medical management with AV nodal blocking medications or antiarrhythmic medications is a reasonable first-line approach, catheter ablation is a definitive, most often curable option that has minimal risk and offers the chance of avoiding long-term medications. This chapter covers the epidemiology, diagnosis, and management of SVTs, which include atrioventricular nodal reentrant tachycardia (AVNRT), atrioventricular reentrant tachycardia (AVRT), atrial tachycardia (AT), and others (atrial flutter, inappropriate sinus tachycardia, and junctional tachycardia). Atrial fibrillation, which is more prevalent than all other SVTs combined, are discussed elsewhere. Figures describe the differential diagnosis of tachycardia with narrow and wide QRS complexes, the relationship between the response to intravenous adenosine and the cause of tachycardia, the mechanism of tachycardia induction in patients with dual AV node conduction pathways, and the management of atrial flutter. Electrocardiograms illustrate features of various forms of SVT. This review contains 11 highly rendered figures (included 6 twelve-lead ECGs), 1 table, and 69 references.

Ivabradine in the Treatment of Inappropriate Sinus Tachycardia in Patients after Successful Radiofrequency Catheter Ablation of Atrioventricular Node Slow Pathway

Inappropriate sinus tachycardia (IST) occurs relatively common after catheter ablation of slow pathway in patients with atrioventricular nodal reentrant tachycardia. The treatment of IST symptoms using β-blockers or calcium channel-blockers are often noneffective or not well tolerated. Ivabradine is a new heart rate (HR)-decreasing agent inhibiting sinus node If current. The purpose of the study was to evaluate the efficacy and safety of ivabradine in patients with persistent and β-blocker-resistant IST after successful radiofrequency (RF) ablation of atrioventricular node slow pathway. We enrolled 14 patients (42 ± 11 years; 10 women) affected by IST after RF ablation. Holter monitoring, treadmill stress test, and IST symptoms assessment were performed at baseline and after first, and second month of the study. We observed significant reduction of mean resting HR after 30 and 60 days of ivabradine treatment compared to baseline (P < 0.001). 24-hour Holter monitoring showed a significant reduction of mean HR and mean HR during daily activity (P < 0.001). The study revealed significant improvement in exercise capacity during treadmill exercise test on ivabradine therapy (P < 0.001). Significantly lower incidence of IST-related symptoms were registered after administration of If current inhibitor. After 2 months of treatment no patients reported severe complaints assessed by means of European Heart Rhythm Association score. We did not observe severe side effects during therapy. Ivabradine is an effective treatment option to reduce HR and symptoms in patients with IST after RF ablation of atrioventricular node slow pathway. The therapy with ivabradine is well tolerated even with maximum daily dose.

Clinical Efficacy of Ivabradine in Patients With Inappropriate Sinus Tachycardia: A Prospective, Randomized, Placebo-Controlled, Double-Blind, Crossover Evaluation

The purpose of this study was to investigate the role of ivabradine in the treatment of symptomatic inappropriate sinus tachycardia using a double-blind, placebo-controlled, crossover design. Due to its I(f) blocking properties, ivabradine can selectively attenuate the high discharge rate from sinus node cells, causing inappropriate sinus tachycardia. Twenty-one patients were randomized to receive placebo (n=10) or ivabradine 5 mg twice daily (n=11) for 6 weeks. After a washout period, patients crossed over for an additional 6 weeks. Each patient underwent symptom evaluation and heart rate assessment at the start and finish of each phase. After taking ivabradine, patients reported elimination of >70% of symptoms (relative risk: 0.25; 95% CI: 0.18 to 0.34; p<0.001), with 47% of them experiencing complete elimination. These effects were associated with a significant reduction of heart rate at rest (from 88±11 beats/min to 76±11 beats/min, p=0.011), on standing (from 108±12 beats/min to 92±11 beats/min, p<0.0001), during 24 h (from 88±5 beats/min to 77±9 beats/min, p=0.001), and during effort (from 176±17 beats/min to 158±16 beats/min, p=0.001). Ivabradine administration was also associated with a significant increase in exercise performance. No cardiovascular side effects were observed in any patients while taking ivabradine. In this cohort, ivabradine significantly improved symptoms associated with inappropriate sinus tachycardia and completely eliminated them in approximately half of the patients. These findings suggest that ivabradine may be an important agent for improving symptoms in patients with inappropriate sinus tachycardia.

Heart rate as marker of successful percutaneous renal denervation

228 Cardiovascular Medicine 2012;15(7–8):228–229 A 52-year-old man with long-standing resistant essential hypertension, inappropriate sinus tachycardia and known ischaemic heart disease was referred to our centre for percutaneous renal denervation. The arterial hypertension was treated for six years and multiple drug combinations (angiotensin-converting-enzyme inhibitors, angiotensin receptor blockers, calcium antagonist, β-blockers, diuretics and spironolactone) were tried in the past. His current therapy included metoprolol succinate 200 mg/day, perindopril 5 mg/day, doxazosin mesylate 4 mg/day and ivabradine 7.5 mg twice a day. Diuretic treatment had been used but recently stopped due to patient intolerance. His baseline 24-hour recordings are depicted in figure 1, panel A, and showed a mean blood pressure of 137/96 mm Hg and a mean heart rate was 96 bpm. The procedure was performed in accordance with the manufacturer protocol, under general anaesthesia.

Ivabradine for inappropriate sinus tachycardia: another piece of evidence

This editorial refers to ‘Metoprolol succinate vs. ivabradine in the treatment of inappropriate sinus tachycardia in patients unresponsive to previous pharmacological therapy’ by P. Ptaszynski et al. , on page 116 Prevalence of inappropriate sinus tachycardia (IST) defined by heart rate criteria is estimated to be 1.2% in the middle-aged population.1 Its clinical presentation with polymorphic symptoms of variable intensity, sometimes including debilitating palpitations and general incapacity, is fortunately much less common. Pathophysiological background of this infrequent entity remains poorly understood and several investigations led to rather controversial results.2 Enhanced intrinsic automaticity of the sinus node and/or impairment of cardiac autonomic regulation were suggested. Inappropriate sinus tachycardia has also been linked to the presence of beta-receptor stimulating autoantibodies.3 The clinical features of IST significantly overlap with postural orthostatic tachycardia syndrome, so that extracardiac autonomic system abnormalities may play an important role. For all these reasons, a multidisciplinary model in managing IST patients was proposed.4 Beta-blockers are the cornerstone of pharmacological therapy for IST that may be replaced by or combined with non-dihydropyridine calcium channel blockers. Since this therapy is ineffective or associated with intolerable side effects in approximately one-third of patients, radiofrequency catheter modification of sinus nodal region has been proposed. This approach should be reserved for highly symptomatic patients who are refractory to medical therapy because ablation has no clear acute endpoint and may be associated with significant complications. Also long-term outcomes were disappointing.4 Due to the ‘systemic’ nature of IST, invasive procedure may, however, identify a considerable proportion of associated non-IST arrhythmias that can be cured by radiofrequency ablation more successfully.5 …

Metoprolol succinate vs. ivabradine in the treatment of inappropriate sinus tachycardia in patients unresponsive to previous pharmacological therapy

Inappropriate sinus tachycardia (IST) is a clinical syndrome characterized by excessive resting heart rate (HR) or disproportional increasing HR during exercise. The treatment of IST symptoms using beta-blockers or calcium channel-blockers is often non-effective or not well tolerated. Ivabradine is a new agent inhibiting sinus node I(f) current, resulting in a decrease of HR without haemodynamic compromise. We enrolled 20 patients (36 ± 10 years; 14 women) affected by IST and resistant to previous administered therapy by using beta-blockers or verapamil. After 4 weeks of treatment with metoprolol succinate (up to 190 mg once a day) the therapy was switched to ivabradine up to 7.5 mg twice daily. Holter monitoring and treadmill stress test were performed after 1 and 2 months following start of the study. We observed a significant reduction of resting HR both for metoprolol and for ivabradine compared with baseline (92.8 vs. 90.2 vs. 114.3 b.p.m.; P< 0.001). During daily activity there was an even larger decrease of HR on ivabradine (mean daytime HR 94.6 vs. 87.1 vs. 107.3 b.p.m.; P< 0.001). Ivabradine was very well tolerated whereas in 10 patients on metoprolol we observed hypotension or bradycardia requiring dose reduction. Significantly lower incidence of IST-related symptoms were registered on ivabradine therapy than on metoprolol. Fourteen patients (70%) treated with I(f) blocker were free of IST-related complaints. Metoprolol and ivabradine exert a similar effect on resting HR in patients with IST. Ivabradine seems to be more effective to relieve symptoms during exercise or daily activity.

Frequent Additional Tachyarrhythmias in Patients with Inappropriate Sinus Tachycardia Undergoing Sinus Node Modification: An Important Cause of Symptom Recurrence

Symptom recurrence following sinus node modification (SNM) for inappropriate sinus tachycardia (IST) remains significant despite achieving acute procedural success. The impact of non-IST tachyarrhythmias on symptom recurrence remains poorly characterized. The objective was to determine the prevalence and nature of additional tachyarrhythmias preceding and following SNM for IST. Consecutive patients with IST undergoing SNM at the University of Pennsylvania were studied. SNM was initially performed using an anatomic approach targeting the superolateral crista terminalis under intracardiac echocardiographic guidance and later using an electrophysiologic approach, targeting the site of the earliest right atrial activation during maximum heart rate (HR) with isoproterenol infusion. An effort was made to shift the site more caudally until a decrease of >25% in resting HR was achieved, with a blunted response to isoproterenol and flattening of the P-wave axis in leads III and aVF. Patients were followed for arrhythmia recurrence. Tachyarrhythmias were documented with electrocardiographic monitoring and then characterized during EP study. Thirty-three patients underwent SNM and were followed for a mean of 2.0 ± 1.5 years. During follow-up, 27% developed a non-IST tachyarrhythmia and 18% developed recurrent IST. Additionally, 42% of patients had a non-IST tachyarrhythmia prior to SNM. Non-IST tachyarrhythmias are common in patients with IST before and after SNM. A major reason for symptom recurrence following SNM is development of a non-IST tachyarrhythmia. These tachyarrhythmias should be detected and treated to optimize patient outcomes.

Refractory inappropriate sinus tachycardia successfully treated with radiofrequency ablation at the arcuate ridge

Supraventricular tachycardias similar to sinus rhythm are difficult to evaluate and treat with catheter ablation. In addition to inappropriate sinus tachycardia (IST), curative ablation of atrial tachycardia arising from the crista terminalis is well described. We report the case of a 48-year-old woman with multiple failed ablation attempts for IST successfully ablated on the arcuate ridge. Ultrasound and fluoroscopy-guided mapping and ablation of this specific endocavitary anatomic site may be helpful in certain patients with the diagnosis of IST.

Anti-N-methyl-D-aspartate receptor encephalitis: an emerging cause of centrally mediated sinus node dysfunction

Anti-N-methyl-D-aspartate receptor encephalitis (NMDARE) is a recently recognized form of autoimmune encephalitis that typically affects young women, often as a paraneoplastic syndrome related to ovarian teratoma. Clinical features include psychiatric and neurological disturbances, central hypoventilation, autonomic instability, and cardiac dysrhythmias. The prevalence, nature, and outcomes of cardiac dysrhythmias in patients with NMDARE have not been well described. Records of 10 consecutive patients with NMDARE were reviewed to obtain clinical, laboratory, echocardiographic, electrocardiographic, and radiological data. Patients were all female with an average age of 23 ± 5.5 years. Echocardiograms revealed structurally normal hearts with the exception of mild left ventricular hypertrophy in two cases. Eight patients had inappropriate sinus tachycardia. Six patients developed significant sinus bradycardia, which included periods of sinus arrest in four cases. Five patients manifested both sinus bradycardia and tachycardia. Bradycardia was often triggered by identifiable vagal stimuli. Temporary pacing was instituted in three patients, but permanent pacing was not required in any of the patients. Magnetic resonance imaging (MRI) scans revealed mesial temporal abnormalities in nine patients. In all cases, the dysrhythmias resolved with treatment of the underlying immune disorder with immunotherapy and/or teratoma resection. There was no evidence of dysrhythmia recurrence in any patient at follow-up. Anti-N-methyl-D-aspartate receptor encephalitis is a recently recognized cause of autoimmune encephalitis with a predilection to cause severe sinus node abnormalities. Temporary pacing is occasionally required, but permanent pacing appears to be unnecessary. An analysis of the clinical syndrome coupled with MRI and experimental data may offer insight into central mechanisms of heart rate regulation.

Usefulness of Non-contact Mapping for Radiofrequency Catheter Ablation of Inappropriate Sinus Tachycardia: New Procedural Strategy and Long-term Clinical Outcome

The present study evaluated the clinical benefits of a new therapeutic method of radiofrequency catheter ablation (RFCA) using an EnSite system for inappropriate sinus tachycardia (IST). Six patients with debilitating IST underwent RFCA using EnSite. Using the beta-adrenergic blocker and agonist, the heart rate was controlled between 70 to 150 bpm before and after the RFCA. The areas of the breakout sites (BOSs) were clearly distinguished between those from the normal P-wave zones during rates of less than 100 bpm and those from more upper rate sites during rates of more than 100 bpm using the EnSite system, in accordance with the appearance of tall P-waves (tall P-wave zone) in the IST patients. This was selected as the target for ablation. After the RFCA, the BOSs observed during heart rates of more than 100 bpm moved completely from the tall P-wave zone to the normal P-wave zone in the IST patients. The total number of heart beats and average heart beat on the 24-h Holter monitoring decreased statistically from that before the RFCA to that after, and no adverse heart rate responses was observed after the RFCA. Before the RFCA, the brain natriuretic peptide was elevated, New York Heart Association functional class was worse, and there was an impaired exercise tolerance observed with exercise electrocardiogram testing. The RFCA for the IST significantly improved those parameters. This new therapeutic method for IST using EnSite is effective and produces clinical benefits.

Inappropriate Sinus Tachycardia

Inappropriate sinus tachycardia (IST) is an uncommon form of arrhythmia characterized by an increased heart rate that is out of proportion to a normal physiologic demand. The etiology of IST remains ill-defined and controversial. Clinical presentation of IST is highly variable, from isolated to sustained palpitations, and can cause deterioration in one's quality of life. IST is usually a diagnosis of exclusion and it is important to rule out other causes of sinus tachycardia before reaching a final diagnosis. Evaluation of cardiac autonomic reflex function is essential to support the diagnosis of IST. The treatment of IST aims to target the multiple mechanisms involved in this disease, and multidisciplinary management, including cardiac rehabilitation, pharmacotherapy, and occasionally radiofrequency modification of the sinus node, should be considered. The prognosis is usually benign, although regular follow-up is required to optimize therapy and prevent the onset of tachycardiomyopathy.

Cardiac involvement in diphtheria: Study from a tertiary referral infectious disease hospital

Background: Diphtheria is still a fatal disease even in the era of universal immunization. Diphtheria myocarditis, one of the serious complications of respiratory diphtheria may cause death if not recognized and treated properly. Aims and Objectives: To determine the outcomes of cardiac involvement in respiratory diphtheria. Materials and Methods: One hundred (n = 100) patients with respiratory tract diphtheria were evaluated in respect to cardiac involvement. All patients were closely monitored for a minimum period of 4-6 weeks from the onset of respiratory symptoms. Continuous ECG monitoring including blood biochemistry (SGOT, CPK-MB, and Troponin-T) were done in each case. Results : The most common symptoms were throat pain seen in 94 cases, palpitation in 56 cases, bull neck in 40 cases, shortness of breath in 12 cases, fever in 9 cases, and nasal regurgitation in 8 cases. Most common complication observed was myocarditis seen in 70 patients and majority of patients (60) were asymptomatic. The ECG changes were T wave inversion in 54 patients, inappropriate sinus tachycardia in 38 patients, ST segment depression in precordial leads in 8 patients, Mobitz type II block in 6 patients, Mobitz type I block in 4 patients, RBBB in 4 patients, multiple atrial ectopics in 4 patients, and sinus bradycardia in 2 patients. A total number of five patients died. Conclusions: Myocarditis was commonest and serious complication of respiratory diphtheria. Increase in vaccination coverage and improvement of socioeconomic status are all effective preventive measures to reduce the incidence of diphtheria.

低血糖発作との鑑別が重要であった体位性起立頻脈症候群の1例

A 49-year-old man was referred to our clinic for suspected hypoglycemic symptoms of palpitation, cold sweat, faintness and sinking feeling at movement since 43 years old. The 75 g oral glucose tolerance test showed a decrease in plasma glucose to 56 mg/dl at five hours, but this was not associated with clear hypoglycemic symptoms, and normal plasma glucose level recovered naturally after the test. At 48-hour fasting test, plasma glucose dropped to under 50 mg/dl, but the patient didn't feel hypoglycemia symptom and plasma glucose recovered naturally, but the patient developed cold sweat and hyperventilation after returning to his own room after the test. At that stage, the heart rate increased to 140 beats/min of sinus tachycardia, as confirmed by Holter monitoring. Postural orthostatic tachycardia syndrome (POTS) was suspected because tachycardia occurred only in daytime after an event such as consumption of diet and urination. A head-up tilt test was ordered since sinus tachycardia developed especially on standing. The results showed an increase in heart rate without reduction in blood pressure, confirming the diagnosis of POTS. A repeat head-up tilt test under the use of a beta-blocker showed no increase in heart rate. Though it is generally difficult to distinguish POTS from other forms of tachyarrhythmia, such as inappropriate sinus tachycardia and sinus node reentry tachycardia, and from neutrally mediated reflex syncope (NMS), POTS should be differentiated from hypoglycemia since each condition should be treated differently.

Collateral Nervous Damages After Cryoballoon Pulmonary Vein Isolation

Various types of complications have been reported after atrial fibrillation (AF) ablation using radiofrequency energy, but those have not been well defined when using cryoballoon ablation technique. The objective of this prospective study was to assess types, incidence, and outcome of complications after cryoballoon pulmonary vein isolation (PVI). This prospective monocentric study included 66 consecutive patients (39 males, age 57 ± 11 years) who underwent cryoballoon PVI for symptomatic paroxysmal AF. Phrenic nerve (PN) integrity was assessed by pacing from the superior vena cava during isolation of the right PVs. Before discharge, all patients were subjected to 24-hour Holter electrocardiograms, echocardiography, and esophagogastroduodenoscopy. Cardiac MRI was scheduled between 1 and 3 months postprocedure. At 3.7 ± 1.7 months after ablation, patients underwent clinical review and 24-hour Holter electrocardiograms. The mean number of cryoballoon applications was 10.0 ± 2.1 per patient and 2.5 ± 1.0 per vein. A 28 mm cryoballoon was used in 49 patients (74%) and a 23 mm cryoballoon in the remaining 17 patients (26%). Twelve complications (18%) attributing to collateral nervous damage were noticed in 9 patients: asymptomatic gastroparesis was observed in 6 patients (9%), transient PN palsy (PNP) in 5 (8%), and symptomatic inappropriate sinus tachycardia requiring beta-blocker treatment in 1 (1%). Neither cryoballoon-related esophageal ulceration nor PV stenosis was observed. Gastroparesis and PNP could be observed in a significant number of cases after cryoballoon ablation of AF. These complications are likely due to cryo-induced damages to nervous structures surrounding the heart.

Persistent Atrial Tachycardia Mimicking Inappropriate Sinus Tachycardia: A Case Report

We report on a 57‐year‐old man with atrial tachycardia mimicking inappropriate sinus tachycardia that was sustained for 4 months despite pharmacotherapy. Using a noncontact mapping system (EnSite Array), the atrial earliest activation (EA) site was identified during tachycardia. By infusing the β1 antagonist landiolol and the β1 agonist isoproterenol, we varied his heart rate from 110 to 155 beats per minute. As his heart rate increased, the EA site moved from the top of the right atrial septum near the crist a terminalis to the right atrial append age (RAA). Tachycardia was terminated by multiple applications of radiofrequency catheter ablation to the RAA. Because the EA site of the sinus rhythm was distant from the ablation points, the tachycardia was diagnosed as persistent atrial tachycardia with multiple foci in a broad area around the RAA. On 12‐lead electrocardiogram, the P‐wave morphology in leads V1 and V2 changed from negative to positive upon termination of tachycardia.