external manifestations of cardiac activity. regulation of heart work
TRANSCRIPT
![Page 1: External manifestations of cardiac activity. Regulation of heart work](https://reader036.vdocument.in/reader036/viewer/2022082206/5a65f6097f8b9aaf638b67f5/html5/thumbnails/1.jpg)
External manifestations of cardiac activity. Regulation
of heart work
![Page 2: External manifestations of cardiac activity. Regulation of heart work](https://reader036.vdocument.in/reader036/viewer/2022082206/5a65f6097f8b9aaf638b67f5/html5/thumbnails/2.jpg)
ATRIAL SYSTOLE 0,1sec
![Page 3: External manifestations of cardiac activity. Regulation of heart work](https://reader036.vdocument.in/reader036/viewer/2022082206/5a65f6097f8b9aaf638b67f5/html5/thumbnails/3.jpg)
Ventricle systole 0,33sec
![Page 4: External manifestations of cardiac activity. Regulation of heart work](https://reader036.vdocument.in/reader036/viewer/2022082206/5a65f6097f8b9aaf638b67f5/html5/thumbnails/4.jpg)
VENTRICLE SYSTOLE 0,33sec
![Page 5: External manifestations of cardiac activity. Regulation of heart work](https://reader036.vdocument.in/reader036/viewer/2022082206/5a65f6097f8b9aaf638b67f5/html5/thumbnails/5.jpg)
Sponsored
Medical Lecture Notes – All Subjects
USMLE Exam (America) – Practice
![Page 6: External manifestations of cardiac activity. Regulation of heart work](https://reader036.vdocument.in/reader036/viewer/2022082206/5a65f6097f8b9aaf638b67f5/html5/thumbnails/6.jpg)
VENTRICLE SYSTOLE 0,33sec
![Page 7: External manifestations of cardiac activity. Regulation of heart work](https://reader036.vdocument.in/reader036/viewer/2022082206/5a65f6097f8b9aaf638b67f5/html5/thumbnails/7.jpg)
COMMON PAUSE 0,37sec
![Page 8: External manifestations of cardiac activity. Regulation of heart work](https://reader036.vdocument.in/reader036/viewer/2022082206/5a65f6097f8b9aaf638b67f5/html5/thumbnails/8.jpg)
COMMON PAUSE 0,37sec
![Page 9: External manifestations of cardiac activity. Regulation of heart work](https://reader036.vdocument.in/reader036/viewer/2022082206/5a65f6097f8b9aaf638b67f5/html5/thumbnails/9.jpg)
COMMON PAUSE 0,37sec
![Page 10: External manifestations of cardiac activity. Regulation of heart work](https://reader036.vdocument.in/reader036/viewer/2022082206/5a65f6097f8b9aaf638b67f5/html5/thumbnails/10.jpg)
External manifestations of cardiac activity
• Mechanical (apex beat, pulse)
• Sound (heart tones)
• Electrical (ECG)
![Page 11: External manifestations of cardiac activity. Regulation of heart work](https://reader036.vdocument.in/reader036/viewer/2022082206/5a65f6097f8b9aaf638b67f5/html5/thumbnails/11.jpg)
Sphygmogram
1.Anacrote2. Catacrote3. Incisure4. Dicrotic rise
![Page 12: External manifestations of cardiac activity. Regulation of heart work](https://reader036.vdocument.in/reader036/viewer/2022082206/5a65f6097f8b9aaf638b67f5/html5/thumbnails/12.jpg)
FREQUENCY
MAGNITUDE
VELOCITY
rarus
altus
frequens
tardus
сеler
parvus
PULSUS CHARACTERISTICS
![Page 13: External manifestations of cardiac activity. Regulation of heart work](https://reader036.vdocument.in/reader036/viewer/2022082206/5a65f6097f8b9aaf638b67f5/html5/thumbnails/13.jpg)
SYSTOLIC TONE
components:1. VALVULAR (A-V valves closure)
2. MUSCULAR asynchronous contraction
3. VASCULAR (aorta vibration )
4. TENDON (chordae tendineae tension)
![Page 14: External manifestations of cardiac activity. Regulation of heart work](https://reader036.vdocument.in/reader036/viewer/2022082206/5a65f6097f8b9aaf638b67f5/html5/thumbnails/14.jpg)
SYSTOLIC TONE. PLACES OF BEST HEARING
• heart apex projection (IV-V intercostal space on the left, 1,5-2 cm medial from the medioclavicular line)
•the place of junction of sternum body and xyfoid processus
![Page 15: External manifestations of cardiac activity. Regulation of heart work](https://reader036.vdocument.in/reader036/viewer/2022082206/5a65f6097f8b9aaf638b67f5/html5/thumbnails/15.jpg)
DIASTOLIC TONE
components:1. VALVULAR (semi-lunar
valves closure)
2. VASCULAR (blood rebound )
![Page 16: External manifestations of cardiac activity. Regulation of heart work](https://reader036.vdocument.in/reader036/viewer/2022082206/5a65f6097f8b9aaf638b67f5/html5/thumbnails/16.jpg)
DIASTOLIC TONE. PLACES OF BEST HEARING
• II right intercostal space along the parasternal line (over aorta).
• II left intercostal space along
the parasternal line (over pulmonary artery).
![Page 17: External manifestations of cardiac activity. Regulation of heart work](https://reader036.vdocument.in/reader036/viewer/2022082206/5a65f6097f8b9aaf638b67f5/html5/thumbnails/17.jpg)
Right atrium excitation- ascending part of P-wave
![Page 18: External manifestations of cardiac activity. Regulation of heart work](https://reader036.vdocument.in/reader036/viewer/2022082206/5a65f6097f8b9aaf638b67f5/html5/thumbnails/18.jpg)
Spreading of excitation from SA to AV node – interval PQ
![Page 19: External manifestations of cardiac activity. Regulation of heart work](https://reader036.vdocument.in/reader036/viewer/2022082206/5a65f6097f8b9aaf638b67f5/html5/thumbnails/19.jpg)
Excitation of left part of intraventricular septum – Q wave
![Page 20: External manifestations of cardiac activity. Regulation of heart work](https://reader036.vdocument.in/reader036/viewer/2022082206/5a65f6097f8b9aaf638b67f5/html5/thumbnails/20.jpg)
Excitation of ventricles’ apexes – R wave
![Page 21: External manifestations of cardiac activity. Regulation of heart work](https://reader036.vdocument.in/reader036/viewer/2022082206/5a65f6097f8b9aaf638b67f5/html5/thumbnails/21.jpg)
Spreading of excitation from endocardium to epicardium
- QRS complex
![Page 22: External manifestations of cardiac activity. Regulation of heart work](https://reader036.vdocument.in/reader036/viewer/2022082206/5a65f6097f8b9aaf638b67f5/html5/thumbnails/22.jpg)
Depoloarization in ventricles completed – ST segment
![Page 23: External manifestations of cardiac activity. Regulation of heart work](https://reader036.vdocument.in/reader036/viewer/2022082206/5a65f6097f8b9aaf638b67f5/html5/thumbnails/23.jpg)
Quick final repolarization of the ventricles – T wave
![Page 24: External manifestations of cardiac activity. Regulation of heart work](https://reader036.vdocument.in/reader036/viewer/2022082206/5a65f6097f8b9aaf638b67f5/html5/thumbnails/24.jpg)
MECHANISMS OF HEART REGULATION
•INTRACARDIAC REGULATION
•EXTRACARDIAC REGULATION
![Page 25: External manifestations of cardiac activity. Regulation of heart work](https://reader036.vdocument.in/reader036/viewer/2022082206/5a65f6097f8b9aaf638b67f5/html5/thumbnails/25.jpg)
INTRACARDIAC REGULATION
1.Myogenic
a)Geterometric (Franc-Starling law)
b)Gomeometric (Boudichi “staircase”)
2.Peripherial heart reflexes
![Page 26: External manifestations of cardiac activity. Regulation of heart work](https://reader036.vdocument.in/reader036/viewer/2022082206/5a65f6097f8b9aaf638b67f5/html5/thumbnails/26.jpg)
Franc-Starling law
• The more heart chambers are filled with blood during diastole, the greater force of contraction they develop during systole
• This prevents ventricles from dilation allowing them to eject all the blood
![Page 27: External manifestations of cardiac activity. Regulation of heart work](https://reader036.vdocument.in/reader036/viewer/2022082206/5a65f6097f8b9aaf638b67f5/html5/thumbnails/27.jpg)
Boudichi “staircase”
• At high frequency of stimulation force of contraction increases regardless of the cardiomyocytes length
![Page 28: External manifestations of cardiac activity. Regulation of heart work](https://reader036.vdocument.in/reader036/viewer/2022082206/5a65f6097f8b9aaf638b67f5/html5/thumbnails/28.jpg)
Peripheral heart reflexes
• Are performed by methasympathetic system in the heart
• They restrict Frank-Starling law so that to readjust cardiac output to the systemic BP
• The most prominent reflex is from right atrium to left ventricle
![Page 29: External manifestations of cardiac activity. Regulation of heart work](https://reader036.vdocument.in/reader036/viewer/2022082206/5a65f6097f8b9aaf638b67f5/html5/thumbnails/29.jpg)
Peripheral heart reflexes
• In case of high systemic BP high threshold receptors are activated in right atrium and via cholinergic fibers decrease heart rate & stroke volume in the left ventricle
• In case of low systemic BP low threshold receptors are activated in right atrium and via adrenergic fibers increase heart rate & stroke volume in the left ventricle
![Page 30: External manifestations of cardiac activity. Regulation of heart work](https://reader036.vdocument.in/reader036/viewer/2022082206/5a65f6097f8b9aaf638b67f5/html5/thumbnails/30.jpg)
EXTRACARDIAC REGULATION
•Nervous regulation (SNS, vagus)
•Humoral regulation (Ad, Thyroxin)
![Page 31: External manifestations of cardiac activity. Regulation of heart work](https://reader036.vdocument.in/reader036/viewer/2022082206/5a65f6097f8b9aaf638b67f5/html5/thumbnails/31.jpg)
HEART INNERVATION
![Page 32: External manifestations of cardiac activity. Regulation of heart work](https://reader036.vdocument.in/reader036/viewer/2022082206/5a65f6097f8b9aaf638b67f5/html5/thumbnails/32.jpg)
Mechanism of sympathetic stimulation
• Adrenalin opens Na+ channels• Na+ influx depolarises myocardiocyte’s
membrane• Threshold decreases (“+” batmotrophic effect)• Time of SDD decreases (“+” chronotrophic
effect)• Conductivity increases (“+” dromotrophic effect)• Contractility increases (“+” inotrophic effect)
![Page 33: External manifestations of cardiac activity. Regulation of heart work](https://reader036.vdocument.in/reader036/viewer/2022082206/5a65f6097f8b9aaf638b67f5/html5/thumbnails/33.jpg)
Influence of sympathetic nerve stimulation on AP of the pacemaker ( A – before, B – after stimulation)
ΔV1, Δ V2 – thresholds of depolarization, α1, α2 – angler, showing the steepness of depolarization, t1, t2 – time of slow diastolic
depolarization
![Page 34: External manifestations of cardiac activity. Regulation of heart work](https://reader036.vdocument.in/reader036/viewer/2022082206/5a65f6097f8b9aaf638b67f5/html5/thumbnails/34.jpg)
Influence of vagus stimulation on AP of the pacemaker ( A – before, B – after stimulation)ΔV1, Δ V2 – thresholds of depolarization, α1, α2 – angler, showing the steepness of depolarization, t1, t2 – time of slow diastolic depolarization
![Page 35: External manifestations of cardiac activity. Regulation of heart work](https://reader036.vdocument.in/reader036/viewer/2022082206/5a65f6097f8b9aaf638b67f5/html5/thumbnails/35.jpg)
Mechanism of parasympathetic stimulation
• Acetylcholine opens K+ channels• K+ efflux repolarises myocardiocyte’s membrane• Threshold increases (“-” batmotrophic effect)• Time of SDD increases (“-” chronotrophic effect)• Conductivity decreases (“-” dromotrophic effect)• Contractility decreases (“-” inotrophic effect)