12. Rhythm and conduction disturbances syndromes

REASONS: IHD (in particular, myocardial infarction, angina pectoris against the background of GB or atherosclerosis); myocarditis of various origins (rheumatic, post-influenza, infectious-allergic, toxic, etc.); heart defects (especially mitral stenosis); changes from the central and autonomic nervous system, changes in homeostasis (electrolyte imbalance, hyperthyroidism, etc.); overdose of certain drugs.

Arrhythmias: primary (atypical arrangement of the conduction pathways of the heart, the presence of additional pathways, a feature of the sensitivity of cells - pacemakers to adrenergic

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effect); secondary (complication of the underlying disease); and on pathogenesis - organic and functional.

I. Arrhythmias due to a violation of the automatism of the sinus node:

1. sinus tachycardia;

2. sinus bradycardia;

3. sinus arrhythmia (respiratory).

Pic 3.7 Sinus rhythm

Pic 3.8 Sinus arrhythmia

Sinus tachycardia. Symptoms

1. Increased heart rate from 90 to 120 (130) in 1 minute;

2. Strengthening the sound of heart sounds;

3. On the ECG: shortening of the R-R interval, the QRS complex does not change

Sinus bradycardia. Symptoms

1. a rare pulse (up to 50-40 per minute);

2. a possible weakening of the sonority of heart sounds;

3. on the ECG: an increase in the R-R interval; sometimes a mild increase in the P-Q interval; atrial and ventricular complexes are not changed.

Sinus arrhythmia (respiratory). Symptoms

1. increased heart rate and pulse on inspiration and contraction on exhalation (this defect is eliminated when holding the breath);

2. on the ECG: the duration of the R-R intervals varies moderately with normal duration and shape of the teeth.

Sick sinus syndrome:

Syndrome weakness syndrome can manifest itself in the form of one of the following forms: a) latent form - there are no subjective sensations, it is clinically manifested only by bradycardia, on the ECG - a moderately pronounced sinus bradycardia;

b) manifest (hypodynamic) form - manifests itself as general weakness, dizziness, a feeling of fading in the region of the heart, passing out, speech impairment, paresis of the extremities, a rare pulse, on the ECG - sinus bradycardia, pronounced; in some patients, even attacks of Morgagni-Adams-Stokes are observed;

Short's syndrome (bradycardia-tachycardia syndrome) - is characterized by a repeated alternation of periods of severe bradycardia and tachycardia, due to the appearance of attacks of atrial fibrillation or flutter, supraventricular paroxysmal tachycardia; periodic appearance of sinoauricular blockade.

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Arrhythmia due to disturbance of excitability:

a. extrasystole:

• supraventricular (atrial and atrioventricular); ventricular (from the left or right ventricles),

• polytopic (from different parts of the heart),

• allorhythmia (bigeminia - every second extrasystole, trigeminia - every third, quadrigeminia - every fourth, etc.);

b. paroxysmal tachycardia (supraventricular or supraventricular and ventricular). a) Extrasystole. Symptoms

1. Complaints of palpitations, interruptions, sometimes, short-term ―cardiac arrest‖. Often patients do not feel extrasystoles.

2. 9) On palpation: the pulse is arrhythmic, corresponding to the time of appearance of the extrasystole.

3. 10) With auscultation, the premature appearance of an extrasystolic contraction of the heart, enhanced loud first tone of the extrasystole, the tones are arrhythmic.

4. 11) If extrasystole arises quickly after the usual contraction, then with an extrasystolic contraction, the aortic valve will not open, blood will not enter the aorta and then the pulse wave on the radial artery will not be detected (pulse loss).

5. 12) ECG is a common symptom: premature reduction in the distance R-R in front of the extrasystole is always less than that between normal contractions.

6. 13) ECG with supraventricular extrasystoles.

Atrial extrasystole: P wave - positive, PQ shortened, QRST unchanged. If the extrasystole comes from the upper part of the atrioventricular node, then the P wave is negative; the interval is shortened; the complex has the usual supraventricular form. If extrasystole comes from the middle part of the node, then the tooth P is absent; the QRST complex does not change. If the P wave is negative from the bottom of the node and is located after the QRS complex, the P-Q interval is absent; QRS complex of the usual form. In all cases, compensatory pauses are incomplete.

T.

Pic 3.9 supraventricular extrasystoles(atrial and atrioventricular.

ECG for ventricular extrasystoles: P wave is absent; QRST is deformed, broadened, high amplitude; the T wave is directed back relative to the QRS; the S-T interval directly passes the tooth Complete compensatory pause.

Pic 3.10 Ventricular extrasystole

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2. Paroxysmal tachycardia. Symptoms

1) sudden onset of a sharp heartbeat;

2) a feeling of tightness in the chest;

3) an unpleasant sensation (sometimes pain) in the region of the heart;

4) shortness of breath;

5) general weakness;

6) nausea and vomiting;

1) pallor of the skin;

2) cyanosis with a prolonged attack;

3) swelling and pulsation of the jugular veins with an increased rhythm of up to 180-200 beats per minute;

4) rhythmic pulse (usually more than 160 per minute), small filling;

5) blood pressure may decrease;

6) ECG: frequent rhythm (160 per minute and above); P wave can be registered or hidden in the QRS complex; the shape of the ventricular complex does not change (with the supraventricular form). But with the ventricular form, the QRS complex is deformed and broadened, there is no P wave.

Pic 3.11 Paroxysmal tachycardia supraventricular form and ventricular form

61. Flickering and fluttering: a) atrial fibrillation;

b) atrial flutter;

c) flutter and flickering (fibrillation) of the ventricles.

a) Atrial fibrillation (atrial fibrillation): tachyarrhythmic, bradyarrhythmic, normosystolic.

1. irregularity in the sequence of heart contractions, complete arrhythmia "delirium of the heart";

2. a constant change in the sonority of tones due to the different duration of diastole and different filling of the ventricles (polyphony of tones). With tachyarrhythmias at the apex, polyphony of the 1st tone is heard;

3. the pulse is irregular, of different filling.

4. heart failure

5. ECG:

6. Mandatory signs - the absence of the P wave; all R-R intervals are different;

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7) Optional features - f waves, different in amplitude R waves.

Pic 3.11 Normal ECG and Atrial fibrillation