1/27. Treatment of the bradycardia-tachycardia syndrome with permanent demand pacing.The bradycardia-tachycardia syndrome (paroxysmal supraventricular tachycardia alternating with sinus bradycardia and episodes of sinus node arrest) has previously presented a complicated therapeutic dilemma when excitatory and suppressive drugs have been utilized. A patient with this syndrome successfully treated with a permanent ventricular transvenous demand pacemaker is presented. Various aspects of this syndrome as well as facets of diagnosis and treatment have been reviewed and discussed. Significant underlying cardiac disease was ruled out in this patient by the usual diagnostic methods including left heart catheterization and coronary angiography. An interesting possibility of the relationship of vagal stimulation secondary to hiatus hernia as an etiologic factor in this syndrome has been discussed. The opinion is expressed that the currently preferred method of treatment is the insertion of a permanent transvenous pacemaker alone or in conjunction with antiarrhythmic drugs, preferably digitalis and propranolol.- - - - - - - - - - ranking = 1keywords = digitalis (Clic here for more details about this article) |
2/27. Bidirectional tachycardia a study of five cases.Five patients with bidirectional tachycardia due to digitalis toxicity associated with severe organic heart disease were studied. The origin of the abnormal rhythm was established with the aid of His bundle recordings in three cases and by indirect clues in the others two. In three cases the origin of bidirectional tachycardia was suprahisian while in two patients it was infrahisian. In one patient the transition from junctional to ventricular tachycardia could be observed. Bidirectional tachycardia appears to be a complex arrhythmia in which similar electrocardiographic configuration can be due to different mechanism. digitalis toxicity was often a causal factor.- - - - - - - - - - ranking = 1keywords = digitalis (Clic here for more details about this article) |
3/27. Effect of chronic beta-adrenergic receptor blockade in congestive cardiomyopathy.Adrenergic beta-blocking agents were given to 7 patients with advanced congestive cardiomyopathy who had tachycardia at rest (98 plus or minus 13 beats/min). The patients were on beta-adrenergic receptor blockade for 2 to 12 months (average 5-4 months). One patient was given alprenolol 50 mg twice daily and the other patients were given practolol 50 to 400 mg twice daily. Virus infection had occurred in 6 of the patients before the onset of symptoms of cardiac disease. All patients were in a steady state or were progressively deteriorating at the start of beta-adrenergic receptor blockade. Conventional treatment with digitalis and diuretics was unaltered or reduced during treatment with beta-blocking agents. An improvement was seen in their clinical condition shortly after administration of the drugs. Continued treatment resulted in an increase in physical working capacity and a reduction of heart size. Noninvasive investigations including phonocardiogram, carotid pulse curve, apex cardiogram, and echocardiogram showed improved ventricular function in all cases. The present study indicates that adrenergic beta-blocking agents can improve heart function in at lease some patients with congestive cardiomyopathy. Furthermore, it is suggested that increased catecholamine activity may be an important factor for the development of this disease, as has been shown in animal experiments.- - - - - - - - - - ranking = 1keywords = digitalis (Clic here for more details about this article) |
4/27. His bundle electrogram during bidirectional tachycardia.The case is reported of a 66-year-old woman with bidirectional tachycardia caused by digitalis intoxication. His bundle records demonstrated the presence of two foci, one junctional and the other a fascicular one.- - - - - - - - - - ranking = 1keywords = digitalis (Clic here for more details about this article) |
5/27. Bidirectional tachycardia: two cases and a review.IMPLICATIONS: Bidirectional tachycardia is an uncommon and unique arrhythmia. It typically occurs in patients with digitalis toxicity, but it can also be associated with other causes. There has been controversy regarding the origin and the mechanism of bidirectional tachycardia. Treatment of bidirectional tachycardia involves the correction of reversible factors and the use of some antiarrhythmic medication.- - - - - - - - - - ranking = 1keywords = digitalis (Clic here for more details about this article) |
6/27. Fetal tachycardia: is digitalis still the first-line therapy?Medical treatment of fetal tachycardias has substantially improved neonatal outcome over the past years. digitalis has been often used as first-line therapy in these cases, and more recently the use of several newer agents have been reported. We present four cases of fetal tachycardia with a favorable neonatal outcome after successful treatment with digitalis. Rapid transplacental digitalization appears to be an effective and reliable treatment option for fetal tachycardia, particularly in non-hydropic fetuses. In hydropic fetuses, however, digitalis alone appears to be less effective and administration of a second drug is usually needed.- - - - - - - - - - ranking = 6keywords = digitalis (Clic here for more details about this article) |
7/27. Evaluation of fetal heart rate artifacts, hemodynamics and digoxin treatment in fetal tachyarrhythmia by Doppler measurement of fetal blood flow--case report of a pre-excitation syndrome.A fetal cardiac arrhythmia may cause misleading fetal heart rate tracings with unreliable signs of fetal distress. Assessment of such artifacts and of the hemodynamic relevance of a fetal arrhythmia by alternative methods is necessary for management and therapy. A 28-year-old healthy woman was referred at 30 weeks of gestation because of fetal tachy-brady-arrhythmia, but cw-Doppler assessment of umbilical artery blood flow revealed periods of pseudobradycardia during bigeminal and trigeminal fetal pulse. FHR turned to regular tachycardia, and transplacental digitalization was started. Between 32 and 34 weeks the patient discontinued her digitalis intake, and a fetal pericardial effusion indicated subsequent cardiac failure. Serial pulsed Doppler measurements of fetal aortic blood flow were performed and imminent heart failure was recognized after the digitalis was discontinued and before a pericardial effusion occurred. Furthermore, improvement of fetal cardiac performance secondary to restarting digitalis and also prior to resolution of the pericardial effusion. After spontaneous delivery a wolff-parkinson-white syndrome was diagnosed, and continuation of digoxin treatment was indicated. Cw-Doppler assessment of umbilical artery blood flow was a suitable method to evaluate questionable FHR recordings, and pulsed Doppler allowed monitoring of the therapeutic effect of transplacental digitalization by serial measurements of fetal aortic blood flow.- - - - - - - - - - ranking = 3keywords = digitalis (Clic here for more details about this article) |
8/27. Bidirectional tachycardia. A sustained form, not related to digitalis intoxication, in an adult without apparent cardiac disease.In this paper we report the first adult case of an "idiopathic" ventricular bidirectional tachycardia (BT), in a 57 year old woman. The tachycardia, at the time of our observation, was incessant in type and had a slightly irregular frequency of about 140 bpm. BT initiated and terminated abruptly, without any temporal relationship to the preceding RR interval, or the QRS morphology. The interval between the two alternating QRS patterns often varied over a wide range of values. The BT could be interrupted only by overdrive atrial and ventricular stimulation, but promptly reappeared as pacing was discontinued. Therapy with quinidine associated with propranolol was effective on a long term trial. The vectorcardiographic analysis and the electrophysiologic investigation demonstrated a ventricular origin of the BT, localizing its site of origin to common myocardial tissue, probably near the two left hemifascicles. Our data could not elucidate the electrogenetic mechanism of this ventricular arrhythmia, because of its chaotic behavior.- - - - - - - - - - ranking = 4keywords = digitalis (Clic here for more details about this article) |
9/27. Long-standing bidirectional tachycardia in a patient with hypokalemic periodic paralysis.Bidirectional tachycardia is an uncommon arrhythmia that usually occurs in aged persons with severe myocardial disease or digitalis intoxication, and carries a poor prognosis. This is a report of a young woman with familial hypokalemic periodic paralysis, who has a 13-year history of asymptomatic bidirectional tachycardia in the absence of organic heart disease or digitalis intoxication. association of periodic paralysis and bidirectional tachycardia in this case and four previously reported cases suggests a strong relationship between this arrhythmia and potassium.- - - - - - - - - - ranking = 2keywords = digitalis (Clic here for more details about this article) |
10/27. Incessant ventricular tachycardia in infants: myocardial hamartomas and surgical cure.Infants with incessant ventricular tachycardia (occurring greater than 10% of the day) have generally been described in pathologic studies. This report describes 21 patients with incessant ventricular tachycardia present greater than 90% of the day and night; the age at diagnosis ranged from birth to 30 months (mean 10.5 months). The most common clinical presentation was cardiac arrest (11 patients, in 5 after digitalis for presumed supraventricular tachycardia); another 6 patients had congestive heart failure and 4 were asymptomatic. Three patients had coexisting wolff-parkinson-white syndrome. The rate of incessant ventricular tachycardia ranged from 167 to 440 (mean 260 beats/min) and the QRS duration from 0.06 to 0.11 second. The most common electrocardiographic (ECG) pattern (10 of 21) was right bundle branch block with left axis deviation, but other right and left bundle branch block patterns were observed. Conventional and investigational antiarrhythmic agents (nine patients received amiodarone) failed to eliminate incessant ventricular tachycardia in all. Electrophysiologic studies localized incessant ventricular tachycardia to the left ventricle in 17 (to the apex in 2, the free wall in 9 and the septum in 6) and to the right ventricular septum in 4. No structural abnormalities were found on the echocardiogram or angiocardiogram. All 21 patients had surgery at an age of 3.5 to 31 months (mean 16). In 15 a tumor was found: 13 myocardial hamartomas (9 discrete, 4 diffuse throughout both ventricles) and 2 rhabdomyomas (1 multiple). myocarditis was found in one patient (the oldest). In four, only myocardial fibrosis was found; results of one biopsy were normal.(ABSTRACT TRUNCATED AT 250 WORDS)- - - - - - - - - - ranking = 1keywords = digitalis (Clic here for more details about this article) |
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