Cardiac Flashcards
What is seen in EKG in ACS?
ST elevations above 1mm in 2 contiguous leads, new LBBB, ST depressions >0.5mm, TWI >1mm, Q waves
What is the timeline to fibrinolytics or PCI in STEMI patients?
Within 12 hrs of symptoms, or 12-24 hrs of clinical/EKG ischemia
30 min to fibrinolytics, 90 min to PCI
What are the guidelines if PCI is unavailable at the institution for STEMI patients?
If DIDO (door in, door out) is <30min and FMC to device is <120min, then transfer for PCI. If there is no lytic contraindication and DIDO >30 min or FMC to device is >120 min, then lytics first then transfer
When are bare metal stents preferred over DES in AMI?
patients with high bleeding risk, unable to comply with DAPT for 1+ years, anticipated surgery within 1 year
What is the danger of receiving streptokinase?
High risk of allergic reactions if you’ve had it before
Which adjuncts are added for fibrinolytic therapy in AMI patients?
Heparin, ASA, and clopidogrel (300mg load then 75mg)
When should beta blockers be used in AMI?
Orally once revascularized, IV only if hemodynamically unstable from AMI
Is there a mortality benefit to revascularizing UA/NSTEMI patients?
Yes, but timeline is 24-48hrs
What is the PCI strategy for patients that receive fibrinolysis for STEMI?
If it works: non-invasive ischemic testing or transfer high risk patients for elective PCI within 24hr
If it doesn’t work (persistent ST elevation, persistent symptoms, develop shock, evidence of artery re-occlusion): PCI
When risk stratifying NSTEMI/UA patients, which patients get a conservative strategy?
No high risk features with plan to get more information (echo, stress test, etc) before proceeding with angio. Otherwise, angio within 24-72hr
What are some EKG changes seen in pericarditis?
Diffuse ST elevation in 8+ leads, PR elevation in aVR with ST depression, PR depression everywhere else
What are some EKG changes seen in cardiac tamponade?
May see RBBB, low voltage
How do you differentiate VT with SVT with aberrancy?
Starts wide then narrows (“warms up” the His bundle)
What are you suspecting when you see a shortened PR interval with slurring of the QRS complex?
An accessory pathway capable of antegrade pre-excitation, such as in WPW. Avoid AV nodal blocking agents
What happens when you give atropine to patients with ischemia to AV node?
Speed up the sinus node but infranodal conduction is worse so becomes more overt heart block
Which meds cause prolonged QT?
SSRI/SNRIs, abx (macrolides, fluoroquinolones, azoles), antiarrhythmics, antipsychotics, triptans, methadone
What are the EKG changes seen in Brugada syndrome?
ST elevations in V1-3 with a RBBB appearance, J point elevation and a gradually sloping or biphasic T wave. Sodium channel blocking antiarrhythmics (ie procainamide) can reveal this in some patients. Tx with amiodarone, AICD and quinidine, potentially ablation.
Which subgroup of afib patients should receive adjunctive digoxin and not CCB therapy?
LV dysfunction/HF. No chronic digoxin monotherapy as it has increased mortality
What EKG changes are seen with digoxin toxicity?
Bidirectional VT, atrial/junctional/ventricular VT, severe sinus bradycardia or heart block
What is a VVI pacemaker vs VOO?
VVI (vent/vent/inhibitor) blocks aberrant beats, while VOO is driving the pacing regardless of what the native heart is doing
What are some differences between sinus node dysfunction vs vagal-mediated bradycardia?
Favors SN dysfunction: meds or prior cardiac Sx, age, not related to position, has a tachy-brady picture
Favors Vagal-mediated: positional, situational (cough//micturition, stretching, etc), sinus brady with AV block
What doses of dopamine have more beta activity versus alpha activity?
Beta- 5-10 mcg/kg/min
Alpha- above 10 mcg/kg/min
Why do 50% of patients with AMI have sinus bradycardia?
Disruption of blood flow to SA node artery and increased vagal tone in the first 6 hrs after an inferior wall MI
How are bradyarrhythmias treated in setting of AMI?
Symptomatic, sinus pauses >3 sec, HR <40 + hypotension
Specifically transvenous pacing if the following:
asystole, alternating right and left bundle branch blocks, 2AVB with new BBB, 2AVB with fascicular block and RBBB, or 3AVB