Apex beat. Heart sounds (VI.) Systolic time intervals (XIII.) Department of Physiology Faculty of Medicine Masaryk University 2015 © Kateřina Fialová, Eva závodná, Tibor Stračina Apex beat • External manifestation of heart function • Maximum in 4th or 5th intercostal space on the left (1-2 cm from medioclavicular line) • Observation (inspection), palpation Heart sounds • 1st heart sound: Closing of mitral and tricuspid valves • 2nd heart sound: Closing of aortic and pulmonary valves • systolic pause: Time interval between 1st and 2nd heart sounds • diastolic pause: Time interval between 2nd and 1st heart sounds • 3rd heart sound: In first part of diastole, physiological in young people; in elderly people sign of decreased compliance of LV (hypertrophy) Heart sounds 1st heart sound - CHARACTERISATION • Vibration of mitral and tricuspid valves due to their rapid closure (because of increase of pressure in ventricles above the pressure in atria in the beginning of systole) • Low-frequency sound takes 100 ms • Circa 50 ms after beginning of QRS • Maximum in region of apex beat (laying on left side) • Clinically relevant: assessment of loudness of heart sound – intensification or attenuation, or splitting Heart sounds 2nd heart sound - CHARACTERISATION • Vibration of aortic and pulmonary valves due to their rapid closure (because of decrease of pressure in ventricles under the pressure in aorta at the end of systole) • High-frequency sound has two components – aortic and pulmonary; physiological splitting in inspiration (unsplit when the subject is holding his/her breath in expiration) • Maximum in region of apex beat (laying on left side) • Clinically relevant: assessment of loudness of heart sound – intensification or attenuation, or splitting Heart sounds • Auscultation – By ear – By stethoscope – By microphone - phonocardiography Heart sounds • Places of optimal audibility of particular valves Aortic valve Tricuspid valve Mitral valve Pulmonary valveA T M P T A P M Heart sounds • Timing of heart sounds: ECG + phonocardiography Heart cycle SYSTOLE DIASTOLE Isovolumetric contraction (IVC) Isovolumetric relaxation (IVR) Ejection phase (EP) Filling phase (FP) POLYGRAPHY – recording of several physiological quantities (signals) in the same time PHONOCARDIOGRAPHY - recording of heart sounds (by microphone) ELECTROCARDIOGRAPHY (ECG) SPHYGMOGRAPHY - recording of arterial pulse wave systole diastole IVC EP IVR FP systole diastole IVC EP IVR FP aorta a. carotis The record of pulse wave from carotid artery is shifted against the record from root of aorta! systole diastole IVC EP IVR FP How can we measure length of heart cycle? systole diastole IVC EP IVR FP RR interval STK - STK S1 - S1 DTK - DTK How can we measure length of heart cycle? systole diastole IVC EP IVR FP How can we measure length of systole and diastole? systole diastole IVC EP IVR FP S1 – S2 S2 – S1 How can we measure length of systole and diastole? systole diastole IVC EP IVR FP How can we measure length of isovolumetric contraction and ejection phase? systole diastole IVC EP IVR FP LVET LVET = left ventricle ejection time = EP IVC could be directly measured in sphygmorgaphy recorded from root of aorta. Due to shift of carotid artery record, we use calculation: IVC = systole – ejection phase = S1S2 - LVET How can we measure length of isovolumetric contraction and ejection phase? systole diastole IVC EP IVR FP How can we measure length of electromechanic systole a preejection period? systole diastole IVC EP IVR FP QS2 Electromechanical systole: QS2 Preejection poriod - calculation: PEP = QS2 - LVET Electromechanical latency (EML) EML = QS2 – S1S2 EML How can we measure length of electromechanic systole a preejection period?