Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Ventricular Flutter”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,621 records · Page 90Linked to original sources

[Cardiac involvement in polymyositis--dermatomyositis associated with Sjogren's syndrome].

A 41 years old woman with polymyositis-dermatomyositis with cardiac involvement is presented. The patient evolved with congestive heart failure, the electrocardiogram showed a left anterior hemiblock, lack of progression of R waves from V1 to V4 and unspecific ST and T alterations. Echocardiogram and cardiac catheterization showed global ventricular disfunction and pulmonary hypertension. An endomyocardial biopsy performed at the apex of the right ventricle showed mononuclear inflammatory infiltration, myocardial fiber degeneration and fibrosis. Initially, the patient responded well to diuretic, vasodilator and steroid therapy. Posteriorly she developed an atrial flutter that required electrical cardioversion and later died suddenly during the course of an acute pneumonia.

Adult↗

[Atrio-ventricular conduction in patients with permanent right-ventricular stimulation. I. Possibilities of evaluation by the method of trans-esophageal electrocardiogram].

UNLABELLED: We analyzed 214 patients with permanent, VVI mode stimulation divided in 5 groups. Group I 89 patients (pts) with sick sinus syndrome (sss) (mean age 60 +/- 14 yrs), group II 21 pts with sss and atrioventricular (a-v) conduction disturbances (mean age 54 +/- 19 yrs), group III 72 pts with a-v block, but without intraventricular conduction disturbances (mean age 68 +/- 11 yrs), group IV 20 pts with a-v block and registered bundle branch block (mean age 67 +/- 7) and group V 12 pts after His bundle ablation (mean age 51 +/- 20 yrs). In all pts we recorded leads I, II, III, V1, V6 and oesophageal (oe) on Mingophon 7 (Siemens-Elema) with paper speed 50 mm/s. All recordings were performed during basic and magnetic rate of the pulse generator. We could analyzed ventriculo-atrial (v-a) conduction in group I-IV respectively in 89.9%, 95.3%, 84.7%, 100%, 83.3% and in all population in 89.2% cases. In 23 pts (10.8%) we could not analyzed v-a conduction due to atrial flutter or fibrillation. V-a conduction was present in groups I-IV in 61.2%, 35%, 21.4%, 45% and 10% cases respectively. CONCLUSIONS: 1. In group patients with sick sinus syndrome and VVI stimulation ventriculo-atrial conduction was recorded in most cases. 2. Ventriculo-atrial conduction was recorded in part of the population with atrio-ventricular block. 3. Frequency of ventriculo-atrial conduction phenomenon is dependent on degree of a-v block. 4. Transesophageal recording of ventriculo-atrial conduction phenomenon in patients with implantable VVI pacemaker is simple, noninvasive and useful method for clinical practice.

Adolescent↗

Early clinical results with VDD pacing in patients with atrioventricular block.

In patients with intact sinus node function and atrioventricular block III(o) VDD pacing with a single pass lead may have advantages compared to conventional DDD systems. The purpose of this study was to evaluate the reliability of a new VDD pacemaker with regard to problems encountered with the implantation and the stability of the atrial sensing potential in the postoperative course. 24 patients (10 male, 14 female; age 61 +/- 17 years) underwent implantation of the Intermedics UNITY 292+07 VDD pacemaker. Patients were analyzed postoperatively with respect to stimulation parameters applied. The mean follow-up was 10+/- 3 months. While early on 23 of 24 patients were paced in a VDD mode, one patient was programmed to the vvi mode due to atrial flutter. One patient died early after aortic valve replacement, while another lost his atrial sensing one month postoperatively. Two patients were reprogrammed to the vvi mode because of atrial arrhythmias. The other 20 patients demonstrated stable atrial sensing potential aside from unchanged ventricular stimulation parameters. No infectious or unchanged ventricular stimulation parameters. No infectious or technical problems were observed. From these results it is concluded that VDD pacing may represent an excellent alternative in patients with intact sinus node function and AV block III(o). The atrial sensing was found to be reliable with the additional technical advantage that the single pass lead is less prone to dislocation than the atrial leads in DDD pacing.

Adolescent↗

ICD hardware failure associated with multiple internal shocks.

The delivery of 37 shocks by an ICD within 20 minutes, in response to T wave oversensing during atrial flutter, resulted in several manifestations of undesirable device behavior. The generator reverted to backup mode, and disabled automatic capacitor reformation, therapy delivery, and automatic gain control. Postexplant analysis of the device revealed damage to the high voltage output section of the circuitry consistent with excessive electrical stress. In rare circumstances, multiple internal discharges can result in serious clinical anomalies in ICD behavior, and possibly in an increase in susceptibility to circuitry damage.

Atrial Flutter↗

[The use of a rate-responsive pacemaker after heart transplantation].

PURPOSE: The indications and the results of pacemaker implant following orthotopic cardiac transplantation. METHODS: Four patients implanted a cardiac pacemaker (PM) in the early post-operative period (PO) of orthotopic cardiac transplantation (from 10th to 16th PO day). The patients were 33 to 55 year-old and the indications to PM were supraventricular arrhythmia (atrial fibrillation or flutter) associated with atrioventricular block in three, and complete atrioventricular block in one patient. Previous to PM implant, patients were submitted to endomyocardial biopsy, which was normal in two patients, evidenced mild rejection in one and moderate rejection in the remaining. A ventricular rate responsive pacemaker was implanted in all patients, with sensors responsive to muscular activity in one patient, and to minute ventilation in three. RESULTS: One patient died in the 20th PO due to acute allograft rejection not controlled by immunosuppressive drugs. Three other patients had satisfactory evolution and the pacemakers were programmed during exercise testing, previous to hospital discharge. Recent evaluation revealed that these patients are in good clinical condition at the 6th, 14th and 24th PO months. Adequate pacemaker function was insured by exercise testing and ambulatory electrocardiographic recording. CONCLUSION: A ventricular rate responsive pacemaker represented a satisfactory mode of pacing, in patients with severe bradycardia, following heart transplantation.

Adult↗

Aortic regurgitation due to non-traumatic rupture of the aortic valve commissures: report of two cases.

Two cases of severe aortic regurgitation due to non-traumatic rupture of the aortic valve commissures are reported. The cause of rupture was hypertension in one patient, but it could not be identified in the other, where microscopic examinations of the aortic wall and the aortic cusps showed no particular pathologic changes. M-mode echocardiography revealed enlargement of the left ventricle, diastolic flutter of the anterior mitral leaflet and diastolic separation of the closure line of the aortic cusps in both patients. Two-dimensional echocardiography showed a downward displacement of the prolapsing motion of the aortic valve cusp during diastole toward the left ventricular outflow tract in one patient, and eccentricity of the coaptation point of the aortic valve without thickening of the cusps in the other. In addition to clinical features of progressive heart failure and characteristic cardiac murmur, echocardiographic studies provided correct diagnosis of aortic valve prolapse resulting from rupture of the aortic valve commissures. Both patients underwent aortic valve replacement successfully.

Aortic Valve↗

[Diagnostic electrophysiological studies].

Clinical cardiac electrophysiology has evolved over the last decades as a technique to study arrhythmias. Programmed stimulation is a potent tool in assessing the detailed mechanisms of most brady- and tachyarrhythmias as well as a method to judge the efficacy of antiarrhythmic therapy and to stratify patients at risk for the development of life-threatening sustained ventricular arrhythmias. We give an overview of the physiologic mechanisms responsible for paroxysmal supraventricular tachycardias, pre-excited tachycardias as well as sustained ventricular tachycardia in coronary artery disease. Benefit and limitations in assessing the risk for life-threatening tachyarrhythmias in clinically important situations are briefly discussed.

Atrial Flutter↗

[Atrioventricular junction ablation: therapy of refractory atrial tachyarrhythmia].

OBJECTIVES: To assess the safety and efficacy of radiofrequency atrio-ventricular junctional ablation. DESIGN: Consecutive group of patients with refractory atrial tachyarrhythmias in whom catheter ablation of the atrio-ventricular junction was performed. SETTING: Cardiology Department at University Hospital. INTERVENTIONS: Atrio-ventricular junctional ablation was performed in 13 patients with a mean age of 53 +/- 13 years. Among six patients there was no evidence of organic heart disease, two had operated congenital heart disease, two had hypertensive heart disease, one had rheumatic heart disease with a prosthetic valve and the other had ischemic heart disease. The indication for ablation was drug-refractory atrial tachyarrhythmia in all patients: atrial fibrillation with uncontrolled rate in eight patients, atrial flutter in three, atrial tachycardia in one and inappropriate sinus tachycardia in one. An average of 3.7 +/- 0.9 anti-arrhythmia drugs was previously ineffective or associated with significant side-effects. Radiofrequency energy was applied between the distal pole of the ablation catheter and an indifferent cutaneous electrode with intensity of 40-65 volts for 30-60 secs. The ablation was initially performed utilizing the classical technique with the ablation catheter across the tricuspid valve. In the case of failure, an alternative method was used, with the ablation catheter positioned in the left ventricular septum. After the procedure a VVI-R permanent pacemaker was inserted in all patients. MEASUREMENTS AND RESULTS: Atrio-ventricular junctional ablation was successful in all patients after an average of 4.4 +/- 3.7 radiofrequency applications. The classical technique was successful in 11 patients (85%). The average amplitude of the His bundle electrogram recorded in the successful sites was not significantly different from the average maximum amplitude at unsuccessful sites (0.1 +/- 0.05 mV vs. 0.17 +/- 0.12 mV). There were no complications related to the procedures. During a mean follow-up of 7 +/- 4 months there was functional and symptomatic improvement in all patients. The only significant complication was an episode of sustained ventricular tachycardia that occurred three months after the ablation in a patient with Tetralogy of Fallot. CONCLUSIONS: In patients with refractory atrial tachyarrhythmias, atrio-ventricular junctional ablation is a safe and effective therapeutic option. The alternative technique should be reserved for cases of unsuccessful ablation with the classic method. Due to its potential significant side-effects, this therapy should be a last alternative option.

Adult↗

[Ion channels and arrhythmias].

Changes in ionic currents through ion channels of the myocardial cell membrane have to be regarded as main cause of cardiac arrhythmias. Three basic arrhythmogenic mechanisms are responsible for the initiation of tachyarrhythmias: 1. The disturbance of normal automaticity in cardiac pacemaker cells dependent on the currents If, ICa-L, ICa-T or IK-ACh,Ado and the occurrence of abnormal automaticity in atrial and ventricular working myocardium based on the currents ICa-L, INa, IK, IK1 or IK-ACh,Ado. 2. Triggered activity which may be recognized by the appearance of early (EAD) or late afterdepolarizations (LAD). EAD are mainly due to inhibition of the outward currents IKr and IKs and are favoured by an increase in the inward currents INa and ICa-L, respectively. Typical arrhythmias are torsade de pointes occurring during treatment with K(+)-channel inhibitors (e.g. sotalol) or in patients with QT-syndrome. LAD may be observed during Ca(2+)-overload of the myocardial cell (digitalis intoxication, catecholamines) and are based on the transient inward current Iti, which is build up by the participation of the currents INa/Ca, INS and ICa-L. 3. Reentry mechanisms are the most frequent cause of tachyarrhythmias. They originate in an anatomically defined excitation circle with unidirectional block. Na(+)- and Ca(2+)-channel dependent disturbances of conduction with long excitable gap may be distinguished from Na(+)-channel dependent disturbances of conduction and refractory period with short excitable gap. Interruption of reentry is possible in the first case by depression of conduction and excitability (Na(+)- or Ca(2+)-channel blockers), in the second case by increase in refractory period (K(+)- or Na(+)-channel blockers).

Action Potentials↗

[Ventricular fibrillation in a patient with the permanent form of junctional reciprocating tachycardia].

A case of a 20 year old young man having the permanent form of junctional reciprocating tachycardia complicated by ventricular fibrillation (VF) is reported. A number of antiarrhythmic drugs either as single or combined therapy fail to control tachycardia. Paroxisms of a faster palpitation which never lasted longer than a few minutes were felt over the last six months before the occurrence of VF. At admission, a narrow QRS tachycardia 250 beats/min was recorded and soon degenerated into VF. After electrical shock with 350J permanent form of junctional tachycardia resumed. Electrophysiologic evaluation identified an accessory pathway with long conducting times in postero-septal location, enhanced atrioventricular node conduction and inducible atrial flutter. The patient underwent successful radiofrequency ablation and is doing well after 18 months of follow-up, being off antiarrhythmic drug and tachycardia free.

Adult↗

Transoesophageal echocardiography-guided cardioversion of atrial fibrillation or flutter. Selection of a low-risk group for immediate cardioversion.

AIMS: Despite exclusion of left atrial thrombi by transoesophageal echocardiography, cardioversion-related thromboembolism has been reported in atrial fibrillation or flutter. To define a low-risk group for cardioversion without previous anticoagulation, patients were selected for immediate cardioversion if there were no thrombi, no echo spontaneous contrast and the outflow velocity of the left atrial appendage was greater than 0.25 m. s(-1)on transoesophageal echocardiography. METHODS AND RESULTS: Two hundred and forty-two consecutive patients referred for cardioversion of atrial fibrillation or flutter with a duration of more than 2 days and no anticoagulation therapy were examined with transoesophageal echocardiography. After the transoesophageal echocardiography examination, patients who were eligible for immediate cardioversion were anticoagulated with low molecular weight heparin (dalteparin) subcutaneously, together with warfarin prior to cardioversion. Dalteparin treatment was continued until the patient had reached therapeutic prothrombin values. Based on the transoesophageal echocardiographic findings the patients were divided into two groups: immediate cardioversion, group A, with a mean age of 62+/-13 years (n=162); or conventional warfarin treatment before cardioversion, group B, with a mean age of 67+/-10 years (P<0.05) (n=80). In group A, lone atrial fibrillation or flutter was more common (53%; 95% CI: 45-61) compared to group B (34%; 95% CI: 23-44, P<0.05), while heart disease was more common in group B (45%; 95% CI: 34-56) compared to group A (31%; 95% CI: 24-39, P<0.05). Echocardiography revealed thrombi in 5% (95% CI: 2.6-8) of the patients, left atrial size was larger, fractional shortening lower, and a higher proportion had impaired left ventricular function in group B. No thromboembolic event occurred at or after cardioversion in any of the patients; however, before planned cardioversion one transitory ischaemic attack, one lethal stroke and one cardiac death occurred in three of the patients with thrombi despite warfarin therapy. One-month follow-up maintenance of sinus rhythm was 75% in group A compared to 45% in group B (P<0.01). CONCLUSION: After using our transoesophageal echocardiographic exclusion criteria (no thrombi, no spontaneous echo contrast and left atrial appendage outflow velocity > or = 25 m. s(-1)) cardioversion can safely be performed in 2/3 of patients with atrial fibrillation or flutter without previous anticoagulation therapy. These patients maintained sinus rhythm significantly better after 1 month compared to patients with prolonged warfarin therapy before cardioversion.

Aged↗