ITE CA2 Cardiac Flashcards
dP/dt
dP/dt (the rate of rise in ventricular pressure) is a good measure of cardiac contractility. Pressures can be measured directly (in the cath lab) or estimated by echocardiography (using the simplified Bernoulli equation). Requires mitral regurg
Sphericity index
Sphericity index (long axis/short axis) is normally >1.5. It is reduced in dilated cardiomyopathy (the LV becomes more globular)
Factors that can result in variable ACT include
Factors that can result in variable ACT include: hemodilution, hypothermia, platelet counts below 30-50 k/mL, and concomitant administration of other medications which affect platelets (e.g. prostacyclin, aspirin, glycoprotein IIb/IIIa inhibitors).
What happens when ultrasound reaches an interface of two tissues with different acoustic impedance?
Acoustic impedance is the capacity of a tissue for transmitting sound. Water and soft tissues have intermediate acoustic impedances, while bone has a high acoustic impedance and air has a low acoustic impedance.
When ultrasound reaches an interface of two tissues with different acoustic impedance (soft tissue-air or soft tissue-bone), most of the ultrasound will be reflected.
Reflection is the basis for correct image formation. Reflection is maximal when the angle of incidence between the beam and the reflecting structure is 90 degrees (giving sharper images).
cranial nerve for carotid sinus baroreceptor reflex
IX Glossopharyngeal
What serum biomarker is first to reach peak after myocardial injury
myoglobin
acute STEMI best identified by wich leads
II, II, aVF
EKG changes with hypocalcemia
prolong QT
in 60% of population this artery supplies blood to SA node
R coronary
ST segment cahnges with sub-endocardial ischemia
ST segment depression
bainbridge reflex
causes increase in HR in response to increased RA fiber pressure and stretch
T wave corresponds to
ventricular repolarization
NYHA class II
excessive fatigue and dyspnea with ordinary activity
concentric hypertrophy of heart ass’d with what type of overload
pressure
sensitivity for combination of EKG leads II and V5 for detecting MI evnts
80%
phase of cardiac myocyte action potential correspond to influx of calcium
2
PEEP effect on venous return to heart
decrease
delta wave
wolff parkinson white
heart sound rapid ventricular filling
S3 - abnormal in all elderly patients
Beck’s triad
for pericardial tamponade
hypotension
muffled heart sounds
JVD
EKG lead best detect right sided arrhythmogenic treacings
II
which papillary muscle has a single-vessel blood supply
posterior
Refraction
Refraction is a source of artifact that occurs when the ultrasound direction is altered. Like reflection, it occurs when the ultrasound reaches an interface of two tissues of different acoustic impedance. Unlike reflection, refraction is most pronounced when the angle of incidence is acute. Thus, a 90 degree angle not only produces sharper images but also reduces artifacts.
How to close or open a PDA
Prostaglandin E1 helps maintain a PDA whereas indomethacin (nonselective COX inhibitor) is the standard medical treatment for closure of a PDA by inhibiting prostaglandin synthesis. Ligation of a PDA is the surgical treatment of choice if medical therapy has failed. Closure results in higher systemic pressures (especially higher diastolic pressures) and patients may require antihypertensive therapy postclosure.
How many people have pfo
25-30%
Multifocal atrial tachycardia
Multifocal atrial tachycardia (MAT) is defined by a heart rate greater than 100 and three or more distinct morphologies of the P wave on an electrocardiogram or rhythm strip. It is commonly seen in patients with pulmonary and cardiac pathologies, especially those resulting in atrial distention and pulmonary HTN. COPD exacerbation is the most common cause.
Indications for one lung ventilation
Absolute indications for one-lung ventilation include:
- Protective isolation of each lung to prevent contamination of the healthy lung: infection (e.g. abscess, infected cyst), massive hemorrhage.
- Control of distribution of ventilation to only one lung: bronchopleural fistula, bronchopleural cutaneous fistula, unilateral cyst or bullae, major bronchial disruption, or trauma.
- Unilateral lung lavage (e.g. pulmonary alveolar proteinosis).
- Video-assisted thoracoscopic surgery (VATS).
Relative indications for one-lung surgery:
- Surgical exposure (high priority): thoracic aortic aneurysm, pneumonectomy, lung volume reduction, minimally invasive cardiac surgery, upper lobectomy.
- Surgical exposure (low priority): esophageal surgery, middle and lower lobectomy, mediastinal mass resection, thymectomy, bilateral sympathectomy.
DAPT for BMS after ACS
1 year because ACS
Preop MI with no intervention. How long wait for surgery
60 days
Medications to avoid in wolff parkinson white
The usual rate-slowing drugs used in atrial fibrillation are not effective, and digoxin and the nondihydropyridine calcium channel blockers (eg, verapamil, diltiazem) are contraindicated because they may increase the ventricular rate and cause ventricular fibrillation
Right coronary artery EKG leads
II, III, aVF (inferior)
LAD EKG leads
septal (V1 and V2) and Anterior (V2-V4)
Circumflex artery EKG leads
Lateral (V5, V6, aVL)
best lead for detecting arrhythmias
II
best lead for dececting anterior and lateral wall ischemia
V5
Idiopathic Hypertrophic sub-aortic stenosis
- pathophys
- physical exam
- management
- factors that worsen it
(IHSS) Thickened interventricular septum/overgrowth of ventricular muscle -> usually antero-lateral; LVOT
Dynamic LVOT obstruction
anterior leaflet is pulled into LVOT during SYSTOLE
Bisferiense pulse: Early rapid peak followed by another peak (unobstructed flow followed by dynamic outflow obstruction)
-SOB, chest pain, syncope, orthopnea, CHF
-management: decrease myocardial contractility (B blocker), normal to slow HR (B blocker), INcrease preload (volume, phenylephrine), increase cardiac output, maintain or increase afterload (vasopressin), avoid arrhythmias
-worsened by increased HR, increased contractility, decreased preload, decreased afterload, arrhythmia
Chemotherapeutic agents: Doxorubicin - MoA - Side effects Bleomycin Cyclophosphamide Methotrexate Vincristine
Doxorubicin - Decrease efficiency of topoisomerase - Cardiotoxicity (LV dysfxn)
Bleomycin - Add glycopeptides and increase free radicals - pulm toxic (avoid high FiO2)
Cyclophosphamide - pro-drug, active drug incorporated into DNA - Cystitis
Methotrexate - inhibition of dihydrofolate reductase - myelosuppression
Vincristine - degradation of microtubulin - peripheral neuropathy (stocking glove), SIADH
Mitral valve postero-medial papillary muscle is supplied by what
Left circumfelx artery OR right coronary artery
Mitral valve antero-lateral papillary muscle blood supply
LAD and Diagonal OR marginal branch of left circumflex artery (dual blood supply)
normal cardiac output
3-8 LPM
Bathmotrophy
Bathmotropic often refers to modifying the degree of excitability specifically of the heart; in general, it refers to modification of the degree of excitability (threshold of excitation) of musculature in general, including the heart.
Mixed venous oxygen equation
SvO2 = SaO2 – [(VO2) / (Hb x 1.36 x Q)]
SvO2: mixed venous saturation SaO2: arterial oxygen saturation VO2: oxygen consumption Hg: hemoglobin
Q: cardiac output
Cardiac accelerator fibers originate from
Cardiac accelerator fibers originate from T1-T4
V4 placement and what cardiac site evaluated
5th intercostal space, mid-clavicular line; anterior
V5 placement and what cardiac site evaluated
5th intercostal space, anterior axillary line; lateral LV
V1 placement and what cardiac site evaluated
4th intercostal space, right sternal border; septal
V2 placement and what cardiac site evaluated
4th intercostal space, left sternal border; antero-septal
PEEP cardiovascular effects
- decrease venous return to heart (decrease RV preload)
- decrease cardiac output (increase intrathoracic pressure)
- increase pulm vasc resistance (increase RV volume -> increase RV afterload)
- Leftward displacement of the intraventricular septum (decrease LV compliance)
Mixed venous O2 sat
directly related to
indirectly related to
SVO2
directly related to O2 sat, cardiac output, hemoglobin
indirectly related to VO2 (O2 consumption)
Cardiac action potential Phase 0 Phase 1 Phase 2 Phase 3
Phase 0 - sodium influx
Phase 1- potassium efflux
Phase 2 - calcium influx
Phase 3 - potassium efflux
Sinoatrial node action potential and describe the numbering
Phase 0- calcium influx
Phase 3 - potassium efflux
Phase 4 - sodium influx
4 is the trough, 0 is steep up, 3 is steep down
Increase contractility
exercise, pharmacologic, adrenergic stim, fever
decrease contractility
acidosis, hypOthermia, pharmacologic (B blocker)
U wave on EKG
hypokalemia
Carotid sinus efferent branch
CN X
Hemodynamic goals for aortic regurg
Sinus rhythm, HR slightly fast (80s), Reduce afterload, maintain preload, maintain contractility
Protamine reaction types
1) brief hypotension (likely 2/2 histamine release)
2) anaphylactoid generalized reaction; and
3) Acute pulmonary hypertension, sudden rise PA pressure, RV failure, hypotension (2/2 LV underfilling consequent to RV dysfunction)
The severity of the reaction had no relation to the dose of protamine.
intra aortic balloon pump inflates at
onset of diastole
HOCM hemodynamic goals
Anesthetic goals should be to minimize sympathetic stimulation, expand intravascular volume, and minimize decreases in left ventricular afterload.
(decrease HR, increase pre-load, increase afterload)
most sensitive non-invasive modality for detecting a venous gas embolism
doppler ultrasound
electrolyte risk factors for torsades de pointes
hypokalemia, hypomagnesemia
Dissection stanford classification
A - involves the ascending aorta and/or aortic arch, and possibly the descending aorta
B - involves the descending aorta or the arch (distal to subclavian), without involvement of the ascending aorta
Which cardiovascular medication has a known antidote
digoxin
BP changes after placing aortic cross clamp during aortic aneurysm repair
hypertension above the clamp and hypotension below the clamp
where place a-line and pulse ox during mediastinoscopy
R rad a-line and L finger pulse ox
R a-line allows you to be aware of surgical compression on the inominnate artery. Pulse ox on right hand to monitor same thing
when measuring cardiac output by thermodilution, increased injection volume will over/under estimate output
underestimate
red vs blue doppler
For red vs blue Doppler, BART: Blue Away, Red Towards.
Obstructive shock
- findings
- causes
Obstructive shock presents with
decreased CI,
increased CVP, and
increased SVR,
but additional context information or additional tests such as echocardiography are usually required for diagnosis.
Obstructive shock is due to an obstruction to cardiac output, most likely due to pericardial tamponade, pulmonary embolism, or a tension pneumothorax.
normal values CVP: PCWP: CI: SVR:
CVP: 2-6 mm Hg
PCWP: 6-12 mm Hg
CI: 2.5-4 L/min/m2
SVR: 800-1200 dynes*sec/cm5
main blood supply for anterior wall
LAD
main blood supply for inferior wall
right coronary
main blood supply for lateral wall
circumflex
main blood supply for interventricular septum
R coronary and LAD
According to the POCA registry, the patients at highest to lowest risk of perioperative events is:
According to the POCA registry, the patients at highest to lowest risk of perioperative events is:
1) Unrepaired hypoplastic left heart syndrome (HLHS) due to elevated pulmonary artery pressures
2) Hypoplastic left heart syndrome (HLHS) who has undergone a total cavopulmonary anastomosis (Fontan)
3) Hypoplastic left heart syndrome (HLHS) who has undergone a superior cavopulmonary anastomosis (Glenn)
4) Unrepaired restrictive ventricular septal defect and left-to-right shunting
anterior mediastinal mass
The four features predictive of perioperative anesthetic complications include:
The four features predictive of perioperative anesthetic complications include:
Great vessel compression
Main-stem bronchial compression
Orthopnea
Upper body edema, suggestive of superior vena cava syndrome
papillary muscle with single blood supply
what is the blood supply
posteromedial
RCA
papillary muscle with dual blood supply
and what is the blood supply
anterolateral
LAD and LCCA
rupture of papillary muscle result in
mitral regurg
Most common primary tumor of the heart
Typical location
Metastatic disease more or less common?
Cardiac tumors have the potential to cause:
The most common primary tumor of the heart is a cardiac myxoma, which is typically located in the left atrium.
However, metastatic disease to the heart is not uncommon from adjacent lung or renal cancer. Metastatic lung cancer to the heart is more commonly occurring than primary cardiac malignancy and renal cell carcinoma is well described as having potential to spread to the inferior vena cava and right atrium.
Cardiac tumors have the potential to cause arrhythmias, ventricular obstruction, heart failure, pulmonary edema, pulmonary hypertension, arterial hypoxemia, dyspnea, positional hemodynamic compromise and embolism.
Acoustic impedance depends on what 2 things
Acoustic impedance is the product of the density of a medium and the propagation speed of sound through that medium. Ultrasound reflections that occur at the interface of different mediums are due to the changes in acoustic impedance. Since propagation speed changes slightly between biological mediums, acoustic impedance is primarily dependent upon density.
How ensure adequate cerebral cooling prior to stopping circulation?
Goal temp?
Full flow CPB is maintained 20-30 minutes after reaching goal temperature to ensure adequate cerebral cooling prior to stopping circulation. Operative time is aimed at 45-60 minutes or less and is the only factor shown to improve outcomes.
The goal temperature is between 15-22 degrees, although slightly higher temperatures may be acceptable for periods of arrest shorter than 30 minutes.
Valve better seen on TTE than TEE
Pulmonic
etCO2 in septic shock
Decreased
Pacemaker placement is indicated in
Second degree AV block
Third degree AV block
Any symptomatic bradyarrhythmia
Refractory supraventricular tachyarrhythmia
HFpEF
EF
left ventricular end-diastolic volume
left ventricular end-diastolic pressure
Patients with heart failure with preserved ejection fraction (HFpEF) have EF greater 50% with a normal left ventricular end-diastolic volume and an elevated left ventricular end-diastolic pressure.
considerations specific for minimally invasive coronary artery bypass
MIDCAB is performed through a small thoracotomy incision on a beating heart which may or may not require single lung ventilation in order to optimize surgical conditions during dissection of the internal mammary artery or anastomosis of the LIMA to the LAD.
Considerations specific for MIDCAB: external defibrillation pads, thoracotomy incision, limited surgical exposure, no CPB (avoids deleterious effects), no cardioplegia, requires anticoagulation, no antifibrinolytics, typically LIMA to LAD, possible need for one lung ventilation or pharmacologic bradycardia, and possible hypotension during ligation of a coronary artery.
Pulmonary embolism on TEE
Pulmonary embolism on TEE:
McConnell’s sign (RV mid-free wall akinesia, spared apex)
60/60 sign,
increased PVR and estimated PA pressures,
enlarged RA / RV / IVC / coronary sinus / hepatic veins,
septal flattening or bowing, and
tricuspid regurgitation.
moderate range for aortic stenosis
peak velocity 3-4
mean gradient 20-40
aortic valve area 1-1.5
Sympathetic activation effect on SA node
Sympathetic activation leads to a sharper, or increased, slope of phase 4 which causes the triggering threshold of the membrane potential to be reached quicker thus leading to depolarization.
Factors the increase the SA node firing rate include the following:
Factors the increase the SA node firing rate include the following: sympathetic stimulation, muscarinic receptor antagonism, beta receptor agonism, catecholamines, hypokalemia, hyperthyroidism.
The two methods of managing acid-base balance during CPB
The two methods of managing acid-base balance during CPB are noted as pH-stat and alpha-stat management. A pH-stat management technique corrects the alkaline drift by maintaining a neutral pH during hypothermia. Alpha-stat management allows the natural alkaline drift to occur without correction.
pH-stat management
During pH-stat management, CO2 is added to the oxygenator or the CPB “sweep” may be reduced (the sweep mechanism removes CO2 from the CPB circuit). The addition of CO2 to the circuit increases total body CO2 in order to maintain pH neutrality despite the continuous reduction in core temperature
Advantages of pH-stat management include increased speed of homogenous cerebral cooling through cerebral vasodilatation, reduced CMRO2, increased CBF, and improved oxygen delivery to tissue. Disadvantages include increased delivery of embolic load to the brain and loss of cerebral autoregulation.
Frank-Starling shifts
A shift in the Frank-Starling curve up or down depicts changes in contractility, with upward shifts showing positive inotropy and downward shifts suggesting negative inotropy.
the most common etiology of hypotension following initiation of CPB
The acute hemodilution of the patient’s blood with the large volume of crystalloid solution is the most common etiology of hypotension following initiation of CPB
The leads of a permanent transcutaneous pacemaker are implanted into the ______
The leads of a permanent transcutaneous pacemaker are implanted into the endocardium.
IABP inflation/deflation timing
Because the balloon inflates during diastole, it increases coronary perfusion pressure (increases supply) and because it deflates suddenly right at the time the ventricle is about to eject blood, it decreases afterload (decreased wall tension -> decreased oxygen demand).
