Persistent Atrial Standstill Research Articles

Clinical presentation, management, and survival in dogs with persistent atrial standstill in the United Kingdom

ObjectivesTo investigate the clinical and echocardiographic presentation of dogs with persistent atrial standstill (PAS), identify variables measured at first presentation that could predict their survival, and document the progression of the disease after pacing. Materials and methodsRetrospective study of medical records of dogs diagnosed with PAS at three referral hospitals of the United Kingdom over seven years. ResultsTwenty-six dogs were diagnosed with PAS during the study period. Median age of the population was three years (range: seven months–12.5 years). The most common clinical sign was syncope (14/26). Twenty-four dogs received artificial pacemakers (PM). Major complications after PM implantation were observed in four dogs (four/24). Serial echocardiographic examinations showed that cardiac dimensions of PAS dogs with left atrial or left ventricular dilation at first presentation did not return to reference range after pacing. Further dilation of the cardiac chambers, recurrence of congestive heart failure (CHF), or development of new episodes of CHF were documented in seven, four, and 10 PAS dogs, respectively, despite pacing. Median survival time for cardiac-related deaths after PM implantation was 1512 days (18–3207). Neither CHF nor echocardiographic variables at presentation predicted survival after PM implantation in PAS dogs. ConclusionsPersistent atrial standstill (PAS) is an uncommon bradyarrhythmia, occurring in young adult dogs. Affected dogs were often presented with syncope. Whilst syncope resolved, cardiac remodeling persisted after PM implantation. Long-term survival was favorable after PM implantation and was not predicted by congestive status or cardiac chamber size at first presentation.

Permanent transvenous pacemaker placement in a Terrier with sick sinus syndrome

Pacemaker therapy is generally considered necessary in patients with symptomatic bradycardia that does not respond to medical management. Common arrhythmias requiring implantation of a permanent pacemaker include third degree atrioventricular (AV) block, high grade second degree AV block, sick sinus syndrome and persistent atrial standstill. This patient care report discusses the diagnosis and treatment of a tTrrier with sick sinus syndrome.

Atrial standstill in the newborn: a case report

Introduction. Persistent atrial standstill is a rare syndrome characterized by absence of mechanical and electrical atrial activity. The article presents a unique case of atrial standstill in the newborn patient with tachyarrhythmia.Brief description. The first manifestation of atrial standstill in the patient was heart failure (HF) manifestations and wide-complex tachycardia according to electrocardiography, which was identified as ventricular tachycardia. At the local outpatient clinic, the child was prescribed with antiarrhythmic therapy (AAT), which decreased heart rate. Three months later, a transesophageal electrophysiological study was carried out in our center in order to determine the arrhythmia origin. A multiform idioventricular rhythm with a heart rate of 46-119 beats per min was diagnosed, atrial pacing spike (A waves) was not recorded. Given bradyarrhythmia, hemodynamic abnormalities on echocardiography (significant atrial enlargement, decreased contractility), the patient, in order to prevent the risk of sudden cardiac death, underwent implantation of single chamber pacemaker in VVIR mode and bipolar ventricular lead. Anticoagulant therapy was prescribed. After 6-month follow-up, relief of HF symptoms and an increase in left ventricular contractile function was noted.Discussion. Timely diagnosis and implantation of pacemakers allowed avoiding AAT and minimizing the HF symptoms. Continuous ventricular pacing and anticoagulant therapy are important in HF prevention.

Pathological Features of Persistent Atrial Standstill Syndrome in Three Dogs

The hearts of three dogs, clinically diagnosed as having persistent atrial standstill syndrome (PAS), were studied post mortem. The most significant gross findings in the hearts of all three dogs were dilatation and marked reduction in the thickness of both atrial walls. Histopathologically, all three had widespread progressive loss of the atrial myocardium with replacement by fatty or fibrofatty tissue, consistent with atrial myopathy. The lesion mainly affected the upper half of both atria and was more severe in the epimyocardium and midmyocardium than in the endomyocardium. On the basis of these observations, it is proposed that the atrial myopathy commences in the upper regions of both atria and progresses downwards, as has been demonstrated electrophysiologically in PAS in humans, and extends from the epicardium towards the endocardium.

Survival time with pacemaker implantation for dogs diagnosed with persistent atrial standstill

ObjectivesTo evaluate survival time in dogs with persistent atrial standstill after pacemaker implantation and to compare the survival times for cardiac-related vs. non-cardiac deaths. Secondary objectives were to evaluate the effects of breed and the presence of congestive heart failure (CHF) at the time of diagnosis on survival time. AnimalsTwenty dogs with persistent atrial standstill and pacemaker implantation. MethodsMedical records were searched to identify dogs diagnosed with persistent atrial standstill based on electrocardiogram that underwent pacemaker implantation. Survival after pacemaker implantation was analyzed using the Kaplan–Meier method. ResultsThe median survival time after pacemaker implantation for all-cause mortality was 866 days. There was no significant difference (p=0.573) in median survival time for cardiac (506 days) vs. non-cardiac deaths (400 days). The presence of CHF at the time of diagnosis did not affect the survival time (P=0.854). No difference in median survival time was noted between breeds (P=0.126). ConclusionsDogs with persistent atrial standstill have a median survival time of 866 days with pacemaker implantation, though a wide range of survival times was observed. There was no difference in the median survival time for dogs with cardiac-related deaths and those without. Patient breed and the presence of CHF before pacemaker implantation did not affect median survival time.

Persistent atrial standstill with coronary and cerebral embolism treated with left atrial appendage closure

Persistent atrial standstill with coronary and cerebral embolism treated with left atrial appendage closure

Persistent atrial standstill in acute myocarditis

Atrial standstill manifests as absence of any atrial electrical activity in the surface ECG leads. Persistent atrial standstill secondary to acute myocarditis is extremely rare. 10-year-old girl had atrial standstill and heart failure due to acute myocarditis. After recovery from myocarditis, heart failure resolved, but the atrial standstill persisted. Persistent atrial standstill was treated with permanent pacemaker and anticoagulation. Acute myocarditis may rarely cause atrial standstill that can last even after recovery from myocarditis.

Adult‐onset nemaline myopathy in a dog presenting with persistent atrial standstill and primary hypothyroidism

A nine-year-old neutered female mixed breed dog presented for evaluation following a five-day history of lethargy, inappetence, weakness, abdominal distension and generalised muscle atrophy. Persistent vatrial standstill with a junctional rhythm was identified on electrocardiogram. Echocardiogram identified moderate dilation of all cardiac chambers and mild thickening of the mitral and tricuspid valves. Serology was negative for Neospora caninum and Toxoplasma gondii. Permanent pacemaker implantation was performed in addition to endomyocardial and skeletal muscle biopsies. Cryosections from the biceps femoris muscle showed numerous nemaline rod bodies while endomyocardial biopsies were possibly consistent with end-stage myocarditis. Rod bodies have rarely been reported in the veterinary literature. To the authors' knowledge, this is the first report of adult-onset nemaline rod myopathy and hypothyroidism with concurrent cardiac disease in a dog.

Doppler Evidence of Persistent Left Atrial Mechanical Standstill with Normal P-Waves by Electrocardiogram after Biatrial CryoMaze Procedure for Atrial Fibrillation

A 64-year-old female with exertional shortness of breath and a history of mitral regurgitation with chronic atrial fibrillation (AF) underwent robotically assisted mitral valve repair (34 mm Cosgrove annuloplasty ring; Edwards Lifesciences, Irvine, CA, USA), left atrial appendage (LAA) ligation, and biatrial Maze procedure (CryoMaze; ATS Medical, Inc., Minneapolis, MN, USA). Postoperatively the patient’s electrocardiogram (ECG) was normal sinus rhythm (NSR). A Holter monitor 3 months later (7-day continuous recording) revealed NSR and no episodes of AF. Follow-up ECGs and transthoracic echocardiograms (TTE) were performed 3, 6, and 9 months postoperatively. Each ECG revealed NSR (Fig. 1). Each postoperative TTE was essentially the same. Mitral regurgitation was mild and overall left ventricular (LV) systolic function was normal. Mitral Doppler inflow (Fig. 2), however, failed to demonstrate late diastolic filling (A-wave) and mitral annulus (lateral, septal, anterior, and posterior) tissue Doppler showed no late diastolic velocity (a’; Fig. 3). In contrast, an A-wave was noted with tricuspid Doppler inflow (Fig. 4). Also, the lateral tricuspid annulus demonstrated an a’-wave (Fig. 5). These Doppler findings suggest preserved right atrial (RA) mechanical contraction, but lack of left atrial (LA) mechanical contraction (LA standstill). The mechanism for this finding may

Use of transcutaneous external pacing during transvenous pacemaker implantation in dogs

The aim of this retrospective study was to evaluate the utility of transcutaneous external pacing (TEP) during transvenous pacemaker implantation in dogs. Eighty-two pacemakers were implanted in 77 dogs because...

Mapping and Ablation of Multiple Atrial Arrhythmias in a Patient with Persistent Atrial Standstill after Remote Viral Myocarditis

This is a case of multiple atrial arrhythmias (atrioventricular node reentry and two different focal atrial tachycardias) originating from the remaining atrial myocardium after global scarring of both atria following a remote viral myocarditis. All the induced arrhythmias were successfully treated with catheter ablation.

Persistent Atrial Standstill in Noncompaction Cardiomyopathy

Atrial standstill is a rare form of bradyarrhythmia and consists of a transitory or permanent loss of the electrical and mechanical activity of the atria. It has been described in a few cases of long-standing valvular disease, amyloidosis, myocarditis, and muscular dystrophy. We report on a young female with noncompaction cardiomyopathy that progressed to congestive heart failure. Electrocardiogram showed persistence atrial standstill that was confirmed clinically and by electrocardiomyopathy, Doppler two-dimensional echocardiogram, and tissue Doppler imaging. We assume that worsening of asymptomatic noncompaction and progression to the congestive form of cardiomyopathy could be presaged by the presence of persistent atrial standstill. Thus, persistence of atrial standstill in asymptomatic cardiomyopathy is a sign of poor prognosis.

Enormous bi-atrial enlargement in a persistent idiopathic atrial standstill

A 62-year-old woman came to our clinical attention 21 years ago for non-cardiac problems. The clinical evaluation disclosed a persistent idiopathic atrial standstill (PIAS) with mitral incompetence. The family screening documented a familial form of PIAS with three affected living relatives. During the follow-up, she developed a cerebral thrombo-embolic episode and, 12 years after the diagnosis, she underwent permanent electrical stimulation (VVIR). She is currently …

Long‐Term (13‐Year) Follow‐up of Isolated Atrial Standstill

We describe a case of persistent atrial standstill (PAS) in the absence of other cardiac or extracardiac abnormalities. Long‐term (13‐year) follow‐up of this case suggests that the prognosis of isolated PAS, following institution of permanent pacing, may be benign. A.N.E. 1999;4(3):372–373

Left atrial appendage blood flow in a case of persistent atrial standstill

Persistent atrial standstill, characterized by absence of atrial activity on surface and intracavitary electrograms, absence of atrial mechanical activity, and inability to stimulate the atria electrically, is a rare disorder. Left atrial appendage blood flow has been reported to be related to P wave during sinus rhythm or local atrial electrogram during atrial fibrillation. However, distinct and periodical LAA blood flow was demonstrated in a patient with persistent atrial standstill by transesophageal echocardiography.

Persistent atrial standstill documented over a 22-year period

This international multidisciplinary document is intended to guide electrophysiologists, cardiologists, other clinicians, and health care professionals in caring for patients with arrhythmic complications of neuromuscular disorders (NMDs). The document presents an overview of arrhythmias in NMDs followed by detailed sections on specific disorders: Duchenne muscular dystrophy, Becker muscular dystrophy, and limb-girdle muscular dystrophy type 2; myotonic dystrophy type 1 and type 2; Emery-Dreifuss muscular dystrophy and limb-girdle muscular dystrophy type 1B; facioscapulohumeral muscular dystrophy; and mitochondrial myopathies, including Friedreich ataxia and Kearns-Sayre syndrome, with an emphasis on managing arrhythmic cardiac manifestations. End-of-life management of arrhythmias in patients with NMDs is also covered. The document sections were drafted by the writing committee members according to their area of expertise. The recommendations represent the consensus opinion of the expert writing group, graded by class of recommendation and level of evidence utilizing defined criteria. The recommendations were made available for public comment; the document underwent review by the Heart Rhythm Society Scientific and Clinical Documents Committee and external review and endorsement by the partner and collaborating societies. Changes were incorporated based on these reviews. By using a breadth of accumulated available evidence, the document is designed to provide practical and actionable clinical information and recommendations for the diagnosis and management of arrhythmias and thus improve the care of patients with NMDs.

928-80 Can Electrocardiogram Help to Differentiate Emery-Dreifuss Muscular Dystrophy from Other Muscular Dystrophies?

Emery-Dreifuss muscular dystrophy (EDMD) is a rare X-linked muscular disease with a potentially lethal cardiac arrhythmia. The purpose of this study was to determine if electrocardiogram (ECG) was useful to differentiate EDMD from other muscular dystrophies, mainly facioscapulohumeral dystrophy and limb-girdle muscular dystrophy that usually have a benign course and a good prognosis. Our own experience consists of 3 patients of the same family with EDMD, 2 of them having a persistent atrial standstill during 22 years follow-up. Therefore we have reviewed the ECG patterns of 125 cases of EDMD reported in the literature and found persistent atrial standstill (PAS) in 37 patients (30%) and complete (31 patients, 25%) or incomplete (22 patients, 18%) A-V block. On the contrary no case of atrial standstill was recorded in the patients with the diagnoses of facioscapulohumeral dystrophy or other types of muscular dystrophies based on rigorous clinical criteria. On an other hand, in a survey of the etiologies of 109 cases of PAS, we have found 36 patients with EDMD (33%). Moreover in 27 patients with EDMD who had a 12 lead surface ECG, PAS was associated with a left anterior fascicular block (LAFB) in 14 cases (52%). Conversely in 51 patients without EDMD, PAS was associated with a LAFB in 5 cases only (10%, P < 0.01). 1 The presence of persistent atrial standstill can probably help to differentiate Emery-Dreifuss muscular dystrophy from other muscular dystrophies more especially as a left anterior fascicular block is associated. 2 Pacemaker insertion is recommended in that case to avoid the risk of sudden death.

持続性心房停止をともなった特発性右房拡張症の犬の1例

持続性心房停止をともなった特発性右房拡張症の犬の1例

Permanent Transvenous Pacemaker Implantation in Forty Dogs

Permanent transvenous cardiac pacemakers were implanted in 40 dogs. Electrocardiographic diagnoses included persistent atrial standstill (3 dogs), sick sinus syndrome (8 dogs), and high-grade second-degree or third-degree atrioventricular (AV) block (29 dogs). Thirteen dogs were alive and well 4 to 42 months after pacemaker implantation (mean, 16.9 months). The mean and median survival times of the 26 dogs that died or were euthanatized during the study were 17.9 months and 13 months, respectively. Most of these dogs succumbed to problems unrelated to the arrhythmia and pacemaker implant. One dog was lost to follow-up. Complications associated with permanent transvenous pacemaker implantation included lead dislodgement, infection, hematoma formation, skeletal muscle stimulation, ventricular arrhythmia, migration of the pulse generator, and skin erosion. Lead dislodgement was the most common complication, occurring in 7 of 9 dogs paced using untined electrode leads and in 6 of 30 dogs paced using tined leads. Lead dislodgement did not occur in the only dog paced using an actively fixed endocardial lead. It was concluded that permanent transvenous cardiac pacing is a feasible, less traumatic alternative to epimyocardial pacing in dogs, but that successful use of this technique requires careful implantation technique and anticipation of the potential complications.

Disturbed secretion of atrial natriuretic peptide in patients with persistent atrial standstill: Endocrinologic silence

Persistent atrial standstill is a very rare pathophysiologic condition whose diagnosis is established when both electrical and mechanical silence of the atria are confirmed. To test the hypothesis that secretion of atrial natriuretic peptide is disturbed in patients with persistent atrial standstill, the response of atrial natriuretic peptide secretion and other neurohormonal factors during exercise was investigated in three patients with a rate-responsive ventricular demand (VVI) pacemaker implanted for confirmed persistent atrial standstill. The results were compared with those observed in eight normal subjects and patients with a rate-responsive VVI (Group A) or atrial demand (AAI) (Group B) pacemaker implanted for confirmed sick sinus syndrome.Patients in Group A displayed significant elevation of alpha-human atrial natriuretic peptide secretion both before and during exercise (122.5 ± 14.8 and 207.5 ± 8.3 pg/ml, respectively) compared with those in Group B (55 ± 14.1 and 116.4 ± 51.5 pg/ml, respectively) and the normal subjects (18.9 ± 9.8 and 30.8 ± 19.2 pg/ml, respectively). This indicated development of a nonphysiologic increase in atrial volume or pressure overload, or both, in rate-responsive VVI pacing because of lack of atrioventricular synchrony. However, patients with persistent atrial standstill had undetectable (<10 pg/ml) or almost undetectable secretion of atrial natriuretic peptide as well as lower levels of cyclic guanosine monophosphate in the circulation both before and during exercise. Changes in plasma catecholamines during exercise were similar in patients with persistent atrial standstill compared with the other groups.This study indicates that “endocrinologic silence” accompanies electrical and mechanical silence of the atria, which may constitute a third diagnostic clue to persistent atrial standstill.