Cardiovascular Flashcards
(222 cards)
Acute chest pain that radiates to back?
Acute dissecting aortic aneurysm; usually initiated by an intimal tear
wide, fixed splitting of S2 that doesn’t vary with respiration
ASD
What may lead to eye problems following treatment for an inferior MI (ST elevation in inferior leads)?
Inferior lead MIs are associated with bradycardia; so, pts are often given atropine to treat the bradycardia. Side effect of atropine = eye problems!
What artery does coronary artery occlusion most commonly occur in?
LAD = Left Anterior Descending artery
=> anterior wall MI
*LAD comes off the LCA (left main coronary artery), supplies the apex and anterior interventricular septum
Which coronary artery supplies the SA and AV nodes?
Majority of time –> SA and AV nodes are supplied by the RCA
Which coronary artery supplies the right ventricle?
Acute marginal artery (comes off the RCA)
Which coronary artery supplies the posterior left ventricle?
CFX = Circumflex artery (comes off the LCA)
PD = Posterior Descending artery is supplied by? supplies?
“Right Dominant” heart –> majority of cases (about 80%), RCA supplies the PD, which supplies the inferior part of the Left ventricle
*20% of the time, the PD arises from the CFX (Circumflex artery, which arises from the LCA)
Most posterior part of the heart? What may it cause if it enlarges?
- most posterior part of the heart is the Left Atrium
- If enlargement of Left Atrium –> dysphagia (d/t esophageal compression) or Hoarseness (d/t recurrent laryngeal nerve compression)
CO (Cardiac Output) = ?
CO = SV X HR
(CO = Stroke Volume X Heart Rate)
***note: if HR is too high –> diastolic filling is incomplete –> get decreased CO (ie ventricular tachycardia)
Fick Principle:
CO = (rate of O2 consumption) / (arterial O2 content - Venous O2 content)
MAP (mean arterial pressure) = P =?
MAP = CO X TPR P = Q X R
*TPR = R = Total Peripheral Resistance
Pulse Pressure = ?
Pulse Pressure = Systolic Pressure - Diastolic Pressure
Pulse Pressure is proportional to?
Stroke Volume
Stroke Volume = ?
SV = CO/HR = EDV - ESV
EDV vs ESV
EDV = End-Diastolic Volume = full heart ESV = End-Systolic Volume = empty heart (after pumping out!)
What maintains the CO during early stages of exercise? late stages of exercise?
- Early stages of exercise –> CO maintained by SV
* Late stages of exercise –> CO is maintained by HR
Which 3 factors affect Stroke Volume?
Increased SV when these factors increase/decrease?:
SV CAP:
- Contractility
- Afterload
- Preload
Increased SV when:
- Increased contractility
- Decreased afterload
- Increased Preload
4 factors that increase contractility (and thus increase SV):
1) Catecholamines –> increase activity of Calcium pump in Sarcomplasmic Reticulum (act on Beta-1 receptors)
2) Increased intracellular Calcium
3) Decreased extracellular Sodium (b/c decreased activity of Na+/Ca2+ exchanger, so more Calcium stay inside cell)
4) Digitalis (b/c blocks Na+/K+ ATPase, so decreased extracellular Na+ –> decreased activity of Na+/Ca2+ exchanger –> more Calcium stays in cell, so –> increased intracellular Calcium)
5 factors that decreased contractility (and thus decrease SV):
1) Beta-1 blockade (decreased cAMP–>decreased Protein Kinase A –> decrease intracellular Ca)
2) Heart failure (systolic dysfxn)–> decreased SV in heart failure
3) Acidosis
4) Hypoxia/Hypercapnea (decreased PO2/increased PCO2)
5) Non-dihydropyridine Ca2+ channel blockers (ie Verapamil, Diltiazem)
3 states in which have increased SV:
- Pregnancy (b/c increased blood volume, so increased preload)
- Exercise (b/c increased pre-load + increased catecholamines)
- Anxiety (b/c increased catecholamines)
4 factors that increase myocardial O2 demand:
1) increased afterload
2) increased contractility
3) increased heart rate
4) increased heart size
What is the preload? What states may increase preload?
Preload = Ventricular EDV Increased preload with: -Exercise (slightly) -Pregnancy -Increased blood volume (ie over-transfusion) -Excitement (ie sympathetics)
***Preload Pumps up the heart!
Mean arterial pressure = ?
MAP = 2/3 diastolic pressure + 1/3 systolic pressure