Synopsis - heart rhythm disturbances

Reentry mechanism in the WPW syndrome.

• extrasystoles
- supraventricular
- ventricular
• supraventricular tachycardia
- With a narrow QRS complex (reentrant tachycardia) - with a wide QRS complex
• Atrial flutter
• Atrial Fibrillation
- With tachyarrhythmia
- With slow ventricular activity
• Ventricular tachycardia
• Ventricular fibrillation



Synopsis - heart rhythm disturbances

Heart rhythm disturbances, such as premature beats can occur in healthy and have no pathological significance. More often they are symptom or complication of heart disease with clinical significance and may be cause for a lethal disease (sudden death).

With the exception of emergencies is the treatment of cardiac arrhythmias an electrocardiographic documentation and the clarification of a possible underlying disease.
The electrocardiographic documentation of arrhythmias can occasionally occur even in the short-term ECG and succeed with immediate registration in the attack. The arrhythmia occurs only during exercise occurs, an ECG stress test in required. Because of the large spontaneous variability of quantitative and qualitative assessment of ventricular extrasystoles, a long-term ECG is required.
For unexplained paroxysmal tachycardia recurrence by an electrophysiologic study is useful when a spontaneous documentation fails. It is already mandatory for therapeutic reasons in ventricular tachycardia and ventricular fibrillation as a condition of a goal-oriented treatment. Only when the type of arrhythmia is clearly established, one can determine the individual adequate antiarrhythmic therapy. In syncope, suspected ventricular arrhythmias, acute myocardial infarction and ventricular arrhythmias with significant cardiac disease, a clinical treatment is inevitable.



Diagnosis
History and clinical
Tachycardia, perceived as palpitation, tachycardia, tachycardia, paroxysmal tachycardia and sudden unexpected einsetzend. Depending on Tachykardiefrequenz and cardiac output: shortness of breath, chest tightness, anxiety, dizziness, syncope, pulmonary edema, including heart and circulatory arrest with loss of consciousness (high-frequency ventricular tachycardia and merfiimmern Kam). Question of underlying disease, age, Arrhythmieverstärkung by antiarrhythmic drugs. Adoms-Stokes seizures with bradycardia or high-grade pipe blockages.
ECG recording
• Standard ECG, paroxysmal tachycardia Notice:
- Widened P-wave: paroxysmal atrial fibrillation / flutter
- Shortened PQ interval: LGL syndrome can
- Shortened PQ interval and delta wave: WPW syndrome
- Infarktresiduen: recurrent ventricular tachycardia, flutter Vorhofffimmern /
- AV-block
• Stress test:
Paroxysmal tachycardia by stress often provoked.

• 24-hour ECG:
Important for detection and quantification of ventricular premature beats, paroxysmal atrial fibrillation occasionally registered by reentry tachycardia and ventricular tachycardia in Präexzitationssyndrom rarely detected with 24-hour ECG.

Electrophysiological investigation

(Intracardiac stimulation and recording)
• for tachycardia with narrow QRS complex
Secured Indications: frequent symptomatic tachycardia without sufficient response to medication for the diagnosis, therapy and therapy control setting (specific drugs [combination], catheter ablation, antitachycardia pacemaker or cardioverter implantierbore, defibrillators, antiarrhythmic surgery, possibly HTX). Possible Indication: Patients prefer, the electro-therapeutic method of chronic drug treatment.
No indication: sufficient diagnostic information by means of standard ECG for the arrhythmia and Indentifika-tion to drug therapy decisions.

• Tachycardia with wide QRS complex
n: persistent tachycardia whose origin and mechanism is doubtful, or persistent ventricular tachycardia condition after resuscitation outside the acute phase of myocardial infarction, WPW syndrome with atrial fibrillation and a high ventricular rate or condition after resuscitation; condition after resuscitation without evidence of acute myocardial infarction. No indication: ventricular tachycardia / fibrillation in the acute phase of myocardial infarction, cardiovascular-Sfillstand due to acute ischemia, or other identifiable causes (eg, aortic stenosis, electrolyte disturbances, etc.)
Therapy
general principles:
• influencing the underlying disease
• Elimination of electrolyte disturbances
• exclusion of pro-arrhythmic effects of antiarrhythmic drugs
• Indications for antiarrhythmic therapy: symptomatic arrhythmia,
Patients who are at risk of sudden cardiac death
• Sinus tachycardia
Influence of the causes (anemia, fever, heart failure, hypoxia) symptomatic: digitalis, beta blockers
• Paroxysmal atrial tachycardia
Beta blockers, propafenone, flecainide, etc.; Katheterabiation, anti-arrhythmic cardiac surgery
• Atrial fibrillation / flutter
Calcium antagonists of the verapamil type or beta-blockers. Digitization (normalization of ventricular rate)
Regularization: flecainide, propafenone, quinidine, disopyramide (rare amiodarone, possibly Elektroschockkardioversion transthoracic or intraatrial (atrial flutter and atria-le high-frequency stimulation), rare His bundle ablation or AV node modulation anticoagulation: from planned Electrocardioversion in mitral valve disease. (warfarin), aspirin in other cardiac disease. no reliable thromboprophylaxis.
Präexzitationssyndrome
Transvenous ablation (especially Wolff-Parkinson-White syndrome, AV nodal reentry tachycardia). Drug therapy in symptomatic arrhythmias: beta-blockers, non-Propafe, flecainide, sotalol, Prajmalin (amiodarone in special cases). In Tberapieresistenz and in special cases very rare surgical transection of the accessory rail.
Ventricular Extasystolie
Lidocaine (acute myocardial infarction), mexiletine, ajmaline, quinidine, beta-blockers or sotalol, propafenone, flecainide, disopyramide, amiodarone.
Ventricular tachycardia
Drug therapy: ajmaline (Prajmalin), lidocaine, mexiletine, sotalol, amiodarone, Disopyra bromide, propafenone, flecainide, a combination of antiarrhythmic drugs. Alternative measures: automatic implantable cardioverter / defibrillator such as me-dikamentöser therapy resistance. Katheterabiation in very good localization of the tachycardia (especially with incessant tachycardia 'incessant tachycardia "). Endokardresektion in monomorphic tachycardia and adequate left ventricular function

Antiarrhythmic therapy control after initiation of action
• Standard ECG:
PQ, QRS, QT interval, rest frequency (?)
• Stress ECG:
arrhythmogenic effects under load (?)
• 24-hour ECG:
Evidence of effective suppression of arrhythmias (especially ventricular extra-systoles), recording of adverse effects, eg intermittent sinus bradycardia, AV block inter-mittierender (?); proarrhythmic effects such as significant increases in ventricular-cular extrasystoles, torsade de pointes tachycardia (?).
• programmed ventricular stimulation:
Evidence of effective drug therapy with reproducible triggerable ventricular tachyarrhythmia kulärer (ventricular tachycardia, ventricular fibrillation); proof pro-arrhythmic effects.
Abnormal conduction

Conditions:
- Längsdissoziation a common transport route
- Common start and end points of the pathways
- Different conduction properties (conduction velocity) and / or refractory periods (re-
excitability)
- Unidirectional block
Occurrence:
- AV nodal reentry tachycardia (AVNRT)
- Wolf-Parkinson-White syndrome (WPW syndrome)
- Micro-Reentry: ventricular flutter, ventricular fibrillation
Differential treatment of cardiac arrhythmias

Sinus tachycardia beta-blockers, sedation, cardiac glycosides
Sinus bradycardia
Atropine, elec. Pacemaker
supraventricular extrasystoles beta blockers, verapamil, propafenone, quinidine, disopyramide, Prajmalin!
supraventricular tachycardia
Sedation, Vagusreiz (Karotisdruck, forced breathing), verapamil, adenosine, beta-blocker or sotalol, digitalis, quinidine, disopyramide, ajmaline, Prajmalin, propafenone, electrical therapy (high-frequency stimulation), programmed stimulation, electric shock), catheter ablation!
Atrial fibrillation or flutter, flecainide, propafenone, beta blockers, digitalis, verapamil, quinidine, disopyramide, electrotherapy
SA-or AV-block, Bradyarrhythmia absoluta, carotid sinus syndrome, sick sinus syndrome electrical pacing
ventricular extrasystoles lidocaine (iv only), mexiletine, beta-blockers or sotalol,! propafenone, quinidine, amiodarone, ajmaline / Prajmalin, overdrive stimulation
Acute ventricular tachycardia: lidocaine, ajmaline, mexiletine, Mg-term therapy: sotalol, and Amiotherapie Katheterabiation, possibly surgeon. Measures resistance to therapy
Ventricular defibrillation (200-400 joules) or implantable cardioverter-defibrillator


Causes of cardiac arrhythmias

• Ischemia (coronary heart disease)
• infection (myocarditis)
• Intoxication (glycosides, alcohol, nicotine)
• Electrolyte disturbances (hyperpigmentation, hypokalemia)
• endocrine disorders (hyper-, hypothyroidism)
• mechanical factors (heart disease, trauma)
• Pacemaker malfunction



Sick sinus syndrome
Arrhythmias in sick sinus syndrome

• Sinus bradycardia
• sinoatrial blocks
• Sinus node arrest with escape rhythm
• supraventricular tachycardia
• Atrial Fibrillation
• Atrial flutter
Department of the sinus node syndrome

• Adams-Stokes attack
• Embolism
• heart failure
• Angina pectoris
• Dizziness
• Palpitations
Diagnosis of sinus node syndrome

• Resting ECG, Holter (tape)
• Stress ECG
• atropine test
• Karotisdruckversuch
• atrial stimulation
• rapid atrial pacing (sinus node recovery time)
• Single premature atrial pacing (sinoatrial conduction time)
Therapy for sinus node syndrome
• Drug action:

- Atropine
- Sympathomimetic
- Antiarrhythmics
- Digitalis (?)


• Pacing:

- Pacemaker Implantation
- Atrial stimulation
- Ventricular stimulation
- Bifocal stimulation

- High-frequency atrial stimulation
- Programmed single-or multiple stimulation