Exam 3 - Cardiac Flashcards
LAD: (see changes in leads) divides into: - - supplies: - -
Circumflex:
supplies:
-
RCA:
-supplies the _____
-supplies the _____
-in ____, the RCA gives rise to the _____ which supplies the _____ and _____
if the PDA is supplied by the RCA = _____
if the PDA is supplied by the circumflex = ___
if the PDA is supplied by both the RCA and the circumflex = _____
LAD: V3-V5 divides into: -R bundle branch -L bundle branch supplies: -anterior and posterior papillary muscles -anterolateral L ventricle
Circumflex: I and AVL
suuplies:
-lateral L ventricle
RCA: II, III, AVF
- supplies the posterior heart and inferior (RV and RA) and part of the L ventricle
- supplies the AV and SA nodes before terminating on the inferior surface of the heart as the posterior descending artery
- 70-85% of people; PDA; superior-posterior interventricular septum; inferior wall
- R coronary dominant
- L coronary dominant
- co-dominant
AV valves = -\_\_\_\_\_ valve - -\_\_\_\_\_ valve - Semilunar valves = - \_\_\_\_\_ valve - - \_\_\_\_\_ valve - Sounds S1 = S2 = Atrial waveforms: _, _, _ waves -_ = -_ = -_ =
mitral and tricuspid valves
-mitral - S1; Left 5th interspace just medial to midclavicular line (PMI)
-tricuspid - lateral to lower left edge of the sternum
aortic and pulmonic valves
-aortic - S2; Right 2nd interspace close to sternum
-pulmonic - Left 2nd interspace close to sternum
S1 = closure of AV valves (mitral and tricuspid)
S2 = closure of semilunar valves (aortic and pulmonic)
Atrial waveforms: a, c, v waves (CVP waveform)
-a = contraction of the R atrium
-c = closure of the tricuspid valve (bulges back with closure)
-v = passive filling of the R atrium (in disease states will see huge v waves)
Coronary perfusion is unique in that it is _____ as the _____ (_____). Blood flow to the heart is ___ of CO (____ amount of CO). CBF = _____. Coronary blood flow normally _____. CPP = _____ (_____mmHg). ___ occurs during diastole. Autoregulation in the myocardium is regulated between _____. Coronary MVO2 (myocardial oxygen consumption): _____. _____ is usually the most important determinant of myocardial blood flow. The myocardium extracts ____ of the oxygen in _____ that is delivered to it. If the heart needs more oxygen (_____), it must be met by _____. The effect of VA’s on CBF: _____, _____, and _____. These agents are said to be _____ during anesthesia.
intermittent; coronary arteries are compressed during systole; not much flow to the heart; 5%; least; 225-250cc/min; parallels myocardial oxygen demand (during diastole); DP-LVEDP; 50/60-120mmHg; 75%; 50/60-120mmHg; 8-10ml/min/100grams; myocardial oxygen demand; 65%; arterial blood; increased metabolic demand; increasing coronary blood flow; direct vasodilation; reduces myocardial metabolic demands (MVO2); reduces blood pressure (decreases both preload and afterload); beneficial
Phases of the action potential: Phase 0: \_\_\_\_\_ - - Phase 1: \_\_\_\_\_ - - - Phase 2: \_\_\_\_\_ - - Phase 3: \_\_\_\_\_ - - The cells are refractory to subsequent depolarizing stimuli until \_\_\_\_\_. The refractory period is the \_\_\_\_\_. The absolute refractory period is when \_\_\_\_\_ (this protects cardiac cells from \_\_\_\_\_). During the relative refractory period \_\_\_\_\_ (you have to have a \_\_\_\_\_ to have another AP). Phase 4: \_\_\_\_\_ - - -
Phase 0: depolarization
-rapid Na+ influx
-Na+ channel gates open at -70 to -65mV (threshold potential)
Phase 1: initial repolarization
-overshoot from +2-+30mV
-Na+ gates close
-slow Ca++ influx begins
Phase 2: plateau
-slow Ca++ channels open with QRS complex d/t contractility
-delays repolarization and prolongs the absolute refractory period - allows for ventricular filling and lasts 0.2-0.3 seconds
Phase 3: final (rapid) repolarization
-K+ efflux (T wave)
-Ca++ channels close
phase 4; minimum interval between two depolarizing impulses that are propagated; absolutely no stimuli can cause another AP (this is the first part of the refractory period); premature beats; it is possible to cause another AP, but the intensity of the contraction will be relative to the time in this period; supermaximal impulse
Phase 4: completion of repolarization (RMP)
-Ready for the next AP
-Na+/K+ pump reestablished
-relaxation occurs as Ca++ is actively pumped back into the sarcoplasmic reticulum by Ca/Mg ATPase
Characteristics of atrial AP's - -RMP = \_\_\_\_\_mV - -occurs: \_\_\_\_\_, \_\_\_\_\_, \_\_\_\_\_
SA and AV node AP's - -RMP = \_\_\_\_\_mV (due to \_\_\_\_\_) -\_\_\_\_\_ cells -no \_\_\_\_\_, just phases \_\_\_\_\_ due to \_\_\_\_\_ - Inhalation agents \_\_\_\_\_.
atrial AP's -fast -80 to -90 -bigger upstroke, faster conduction -atria, ventricles, purkinje SA and AV node AP's -slow --55 to -60 due to slow leak of Ca++ -no plateau, just phases 4, 0, 3 since no rapid depolarization -slow phase 4 depolarization depress SA node automaticity directly slowing HR
The baroreceptor reflexes are _____ nerve endings in the walls of the _____ (thin walled dilatations at the origins of the _____) and the _____. These _____ sense alterations in _____ resulting from _____ and respond by modifying _____. The _____ baroreceptors are the dominant baroreceptors and are also more _____. The carotid sinus baroreceptors travel via the _____ a branch of _____. Aortic arch baroreceptors travel by the _____ a branch of _____. Both are _____. _____, _____ and _____ decrease _____ and thus _____.
afferent (sensory) ; carotid sinuses; internal carotid arteries; aortic arch; mechanoreceptors; wall stretch; pressure changes; the frequency at which they fire AP’s; carotid sinus; sensitive; nerve of Herring; CN 9; aortic nerve; CN 10; pressure receptors; aging; HTN; atherosclerosis; arterial wall compliance; baroreceptor reflex sensitivity
The Bainbridge reflex is a homeostatic reflex mechanism that causes _____ following the stimulation of local _____ when BP in the _____ and _____ is _____. It responds more to _____ or _____. Receptors are in the _____. An increase in _____ directly stretches the _____ and causes _____. With an increased filling of the heart the HR _____ if _____. If there is already a high HR then additional fluid and stretch _____. A true _____ rather than a response to _____.
acceleration of heartbeat; muscle spindles; venae cavae; R atrium; increased; volume; preload; atria; preload; SA node; increase in SA node automaticity/increased HR; increases; the HR is low; decrease HR; reflex; local stretch
Measurements: SV = CI = CO = CPP = MAP = SVR = EF =
SV = EDV-ESV 60-80ml/min CI = CO/BSA 2.5-4l/min/msquared CO = HR x SV 4-8L/min CPP = DBP-PAWP (LVEDP) 60-80mmHg MAP = SBP+(DBP x 2)/3 70-105mmHg SVR = (MAP-RAP)x80/CO 800-1200dynes/sec EF = SV/EDV x100% .6 of LV function
Dilated cardiomyopathy is characterized by _____ with impaired _____ (EF typically ___), _____ CO with _____ that can lead to _____, _____ ventricular filling pressures, extreme _____ and _____ and sudden death common. It is _____ hypertrophy. Patients may be _____ with the only evidence being _____. S/s won’t occur until the _____ and _____. Eventually s/s of ___ are evident: _____, _____ and _____. Treatment is similar to the treatment for _____: treat _____, meds, _____, and _____. Anesthetic management is the same as for _____. Avoid _____. Maintain _____. Prevent _____. _____ may be a consideration. _____ reduction and _____ may be needed.
ventricular dilation; myocardial contractility;
Restrictive cardiomyopathy is characterized by _____ ventricles that _____ during _____. _____ is normal. Resembles _____. This is a type of _____ hypertrophy. Clinical presentation includes _____, _____, and all signs of CHF except _____. There is no _____. Anesthetic management uses the same principles as for _____. Maintain _____, avoid _____ because there is very little _____ and need a _____ (_____) to deliver _____, and maintain _____. Careful with regional because of _____.
stiff; ventricular filling; diastole; LV wall thickness; chronic pericarditis; concentric; thromboembolus; Afib; cardiomegaly; effective treatment; cardiac tamponade; IV volume; bradycardia; volume; fast HR; volume; oxygen; NSR; anticoagulation
Hypertrophic obstructive cardiomyopathy is the \_\_\_\_\_ cardiomyopathy. It is characterized by \_\_\_\_\_ to \_\_\_\_\_ produced by \_\_\_\_\_ of the \_\_\_\_\_. The primary anatomic feature is a \_\_\_\_\_ at the \_\_\_\_\_ and one or both \_\_\_\_\_. This is due to an abnormal accumulation of \_\_\_\_\_ in the \_\_\_\_\_. The thickened walls can't \_\_\_\_\_, so they can't \_\_\_\_\_ (\_\_\_\_\_ dysfunction). The thick septum \_\_\_\_\_ the \_\_\_\_\_ so that blood is ejected with \_\_\_\_\_ during systole. The \_\_\_\_\_ is enlarged due to the LV filling resistance. The mitral valve \_\_\_\_\_ which causes more \_\_\_\_\_. So anything that increases aortic impedance and afterload (\_\_\_\_\_) will reduce the \_\_\_\_\_ by pushing back the \_\_\_\_\_. This creates a \_\_\_\_\_ during systole when the hypertrophied septum \_\_\_\_\_ into the \_\_\_\_\_ of the LV. A \_\_\_\_\_ effect is created by the flow of blood through the \_\_\_\_\_. LV function is \_\_\_\_\_ and EF may be \_\_\_\_\_. One cause may be \_\_\_\_\_. Goals of anesthesia may be \_\_\_\_\_ preload, \_\_\_\_\_ hypovolemia, \_\_\_\_\_ sinus rhythm, \_\_\_\_\_ afterload, and \_\_\_\_\_ contractility. Preop: heavy \_\_\_\_\_ Induction: No \_\_\_\_\_ treat hypotension with \_\_\_\_\_ first treatment with \_\_\_\_\_ is detrimental No \_\_\_\_\_
most common; obstruction; LV outflow; asymmetric hypertrophy; intraventricular septal muscle; hypertrophied ventricular muscle; base of the septum; ventricles thicken; cardiac glycogen; ventricular wall; relax; adequately fill; diastolic; narrows; LV outflow tract; increased velocity; left atrium; moves forward and touches the septum during systole; LV outflow obstruction; squatting; obstruction; mitral valve; subaortic pressure gradient; bulges; area under the aorta; “venturi”; narrowed outflow tract; “supernormal”; >80%; Pompe’s disease; increased/maintain; prevent; maintain; increase/maintain; decrease; premedication; ketamine; fluids; inotropes; SAB
Alcoholic cardiomyopathy is a type of _____ cardiomyopathy. It is characterized by a _____ LV, an increased LV _____, and LV _____. Changes in the LV are present in the _____, but it can be present. This is a type of _____ hypertrophy. There is impaired LV _____ and _____ dysfunction which cause _____ and _____. LV systolic function and EF are _____. Anesthetic considerations: _____.
dilated; dilated; mass; dysfunction; absence of CAD; eccentric; relaxation; diastolic; high filling pressures; CHF; normal; “Careful”
Peripartum cardiomyopathy occurs _____ or _____. There is no _____. It can occur in parturients with _____ (not necessarily). This is a form of _____ cardiomyopathy.
During
