Tachycardia-bradycardia syndrome

Treatment of Manic—Depressive Illness. Siace the 1960s, lithium carbonate [10377-37-4] and other lithium salts have represented the standard treatment of mild-to-moderate manic-depressive disorders (175). It is effective ia about 60—80% of all acute manic episodes within one to three weeks of adrninistration. Lithium ions can reduce the frequency of manic or depressive episodes ia bipolar patients providing a mood-stabilising effect. Patients ate maintained on low, stabilising doses of lithium salts indefinitely as a prophylaxis. However, the therapeutic iadex is low, thus requiring monitoring of semm concentration. Adverse effects iaclude tremor, diarrhea, problems with eyes (adaptation to darkness), hypothyroidism, and cardiac problems (bradycardia—tachycardia syndrome). 

Inappropriate sinus bradycardia, sinoatrial block, and bradycardia-tachycardia syndrome (bradycardia followed by supraventricular tachyarrhythmias such as atrial fibrillation) are included in this syndrome. Treatment of sick sinus syndrome is generally based upon the patients symptoms. In general, bradycardia... 

Contraindications to the use of 3 blockers are asthma and other bronchospastic conditions, severe bradycardia, atrioventricular blockade, bradycardia-tachycardia syndrome, and severe unstable left ventricular failure. Potential complications include fatigue, impaired exercise tolerance, insomnia, unpleasant dreams, worsening of claudication, and erectile dysfunction. 

Bradycardia-tachycardia syndrome with the need to long-term antiarrhythmic treatment with drugs other than digoxin... 

Fig. 19.12 Event histogram from a patient implanted with a Trilogy DR+. The indication for pacing was the bradycardia-tachycardia syndrome. Over the past 42 days, the majority of the complexes were in the base rate or sleep rate bins. Rate modulation had not yet been enabled and there were relatively few native atrial rates above 75 bpm. The system functioned in a nontracking mode approximately 3% of the time (AMS bin) with 1,776 mode switch episodes. Based on this event histogram demonstrating the presence of chronotropic incompetence, rate-modulation was enabled.

The bradycardia-tachycardia ("sick sinus") syndrome is a definite contraindication to the use of lithium because the ion further depresses the sinus node. T-wave flattening is often observed on the ECG but is of questionable significance. 

Slurred speech, decreased attention Triad ataxia/dysarthria, hyperacusis Wericke s syndrome Bradycardia Tachycardia Hypertension Hypotension Arrythmias Appetite (decreased) Appetite (increased) Diarrhea Nasal congestion Nausea/vomiting Weight loss Blurred vision Distorted color vision Conjunctival infusion ( red eyes )... 

Arrhythmias Originating in the Sinus Node Sinus bradycardia Sick sinus syndrome Sinus tachycardia Disorders of Impulseformation ... 

Wolff-Parkinson-White syndrome In several cases, the tachycardia was replaced by a severe bradycardia requiring a demand pacemaker after propranolol administration with as little as 5 mg. 

Contraindications are hypotension, cardiogenic shock, marked bradycardia, second or third degree AV-block, Wolff-Parkinson-White (WPW) syndrome, wide complex tachycardia, VT and uncompensated heart failure. 

Sinoatrial disease or the sick sinus syndrome is associated with systemic embolism, particularly if there is bradycardia alternating with tachycardia, or atrial fibrillation (Bathen et al. 1978). 

Nicotinic cholinergic syndrome. Stimulation of nicotinic receptors at autonomic ganglia activates both parasympathetic and sympathetic systems, with unpredictable results. Excessive stimulation frequently causes depolarization blockage. Thus, initial tachycardia may be followed by bradycardia, and muscle fasciculations may be followed by paralysis. (Examples nicotine in addition, the depolarizing neuromuscular blocker succinyl-choline, which acts on nicotinic receptors in skeletal muscle.)... 

Kaplan BM, Langendorf R, Lev M, Pick A. Tachycardia-bradycardia syndrome (so-called sick sinus syndrome ). Pathology, mechanisms and treatment. Am J Cardiol. 1973 31 497-508. 

Cardiovascular An overdose of flecainide may manifest as prolongation of the PR, QRS, and QTc intervals on ECG and the development of bradycardia, premature ventricular complex (PVC), ventricular tachycardia, and fibrillation. The ECG changes observed in flecainide toxicity may resemble Brugada syndrome [24]. 

Otherwise know as Brady-tachy syndrome features alternating periods of tachycardia and bradycardia on the same ECG (Fig. 7.16). Atrial fibrillation or flutter may also be seen on the ECG causing the tachycardia. The bradycardia is caused by sinus pauses or periods of sinus arrest. 

Bradycardia. Dizziness. Headache. Nausea. Sustained ventricular tachycardia. Use cautiously in patients with sick sinus syndrome because of the possibility of sinus bradycardia, sinus pause, or sinus arrest The patient should be hospitalized for initial dosing. Give before meals because food delays rate of absorption. 

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