Cardio Flashcards
QT prolongation: Drugs that increase duration of ventricular action potential
Type 1A anti-arrhythmics: quinidine, TCA, procainamide, disopyramide, phenothiazines
Type III: amiodarone and sotalol
Other causes of prolonged QT
-IC bleed (SAH)
-Systemic hypothermia
-Hypocalcemia (ST portion)
Causes QT shortening
Hypercalcemia
Digital glycosides
Electrical alternans with sinus tachycardia
Cardiac tamponade
What tachyarrhythmia has an accelerated phase 4 depolarization ?
Idiopathic VT and AT
If absent / decelerated phase 4 repolarization: sinus node dysfunction
Infection that can cause AV block typically at the level of the AV node with narrow junctional escape rhythm >40beats/min
Lyme carditis (Borrekia burgdorferi)
- improves after 1 week of antibiotic therapy
Which AV conduction block is Permanent Pacing is required
Mobitz type 2 AV block, high grade AV block, or 3rd degree AV Block that is not reversible or physiologic
OR symptomatic AV block
Adjunctive pharmacologic treatment useful in AV block.
Atropine 0.5 to 2mg IV OR
isopretwrenol 1-4ug/min IV
Normal PR interval
120-200ms
QRS: <-= 100ms
Mechanisms of Pathologic tachycardia
- reentrant reentrant arrhythmias dependent on AV nodal conduction
- large reentry circuits within atrial tissue (atrial flutter)
- focal atrial tachycardia that can be due to automaticity
Postural orthostatic tachycardia syndrome (POTS)
Sinus rate increased by 30bpm or >120bpm within 10 min of standing without hypotension
Reversal agent of Dabigatran
Idarucizumab
Factor X- inhibitors (Rivaroxaban, Apixaban Endoxaban): Andexanet alfa
CHA2DS2VASc and what is the score to start anticoagulation
CHF 1
Hypertension 1
Age >75 2
DM 1
STROKE/TIA, embolus 2
Vascular disease 1
Age 65-75 1
Sex female
HAS-BLED
HTN: 1
abnormal renal and liver function; 1 each
Bleeding disthesis 1
labile INR ( in warfarin)1
Age >65 1
Drug/ alcohol 1 each
Cardia imaging that can additionally detect area of ventricular scar
cardiac MRI with Gd contrast
Class 1 anti arrhythmic drugs and the MOA
Na channel blocker, blocks Na
1C- flecainamide and propefenone
1A- qunidine, procainamide, disopyrimid and TCA
1B- lidocaine, mexilitine
Class 2 anti arrhythmic drugs and the MOA
Beta blockers
Blocks the phase 4 depolarization by suppressing AV/SA nodal activity
Class 3 anti arrhythmic drugs and the MOA
K channel blocker: prolonged phase 3 repolarization
Amiodarone
Ibutalide
Doferilide
Sotalol
Class 4 anti arrhythmic drugs and the MOA
CCB: decreases slope of phase 0,3,4
Prolonged repolarization via AV node.
Non dihydropyridine CCB: Diltiazem and Verapamil
PVC / NSVT with ACS for ICD indication
- > 40days after the AMI: LVEF <30% OR LVEF <35% symptomatic HF (FC II or III)
- > 5days after AMI: decrease LVEF + non sustained VT + inducible sustained VT or VF on EP test
PVCs and NSVT associated with depressed ventricular function and HF, indication for ICD
LVEF <35% NYHA II and III HF (decreased 5-year mortality from 36 to 29%)
Tachyarrhythmia that always indicates structural abnormality or focus of automaticity
Sustained monomorphic VT
Arrhythmias with repolarization abnormalities and genetic arrhythmias syndrome
Acquired long QT: Torsades de pointes
Congenital long QT syndrome: LQTS 1,2,3
short QT syndrome: QTc <0.36s
What is Brugada syndrome
ST segment elevation > 0.2mV + coved ST segment + negative T wave in more than one anterior precordial lead (V1-V3) + episode of syncope or cardiac arrest due to polymorphic VT in the absence of structural disease
Definition of electrical storm or VT storm
3 or more VT or VF episodes in 24 hours
Medical treatment of Brugada syndrome with frequent VTs
Quinidine and catheter ablation
High-output heart failure
B eri beri (vitamin B deficiency)
A nemia
T hyrotoxicosis
A rteriovenous shunt
M yeloproliferative disorder
O besity
C hronic lung disease
C irrosis
Early radiologic signs of acute HF
-upper zone venous distribution
-thickening of interlobular septa
Indication of Cardiac resynchronization therapy in Hf
-NYHA III and IV HFrEF on optimal medical management with mod to severe residual symptoms
-minimally symptomatic pt with QRS >149ms + LBBB
SCD in HF: appropriate candidates for ICD
- NYHA II or III with LVEF <35% regardless of etiology
- post MI on optimal medical management but with residual LVEF =/< 30% even if asymptomatic
-symptomatic HF not caused by CAD <60yo
Which arrhythmia/s have a mechanism of Reentry?
AVNRT, AVRT
atrial flutter
Scar related VT
Which arrhythmia/s have a mechanism of abnormal automaticity?
Enhanced (acceleration of phase 4 repolarization): Idiopathic VT, AT
Suppressed (absent or decelerated phase 4 repolarization): sinus node dysfunction
Which arrhythmia/s have a mechanism of early after depolarization (EADs phase 2/3)?
TdP in long Qt syndrome
PVCs
Which arrhythmia/s have a mechanism of delayed afterdepolarization (DADs phase 4)?
Reperfusiob PVCs/VT
AT and VT with digitalis toxicity
What are the class 1 indication in AV block permanent pacing ?
Class 1:
-Complete heart block (acquired); advanced AV block, mobitz type II evidence of infranodal block
-asymptomatic Mobitz type 1 block, with neuromuscular disease associated with progressive conduction tissue disorder
What are the class IIa indication in AV block permanent pacing ?
- symptomatic first degree AV block
- first degree AV block, asymptomatic with Lamin A/C cardiomyopathy
-symptomatic Mobitz type I block
Class I indication for catheter ablation in Symptomatic AF
-parox or persistent AF with failed drug therapy
-parox or persistent AF and heart failure with reduced EF
Most common genetic cardiovascular disorder and prominent caused if SCR. Before 35
HOCM
sudden death can be due to polymorphic VT/VF
Most common genetic cardiovascular disorder and prominent caused if SCR. Before 35
HOCM
sudden death can be due to polymorphic VT/VF
Hemodynamic hallmark of MS
Abnormally elevated left Atrioventricular pressure gradient
Hallmark of disease progression in MS
Inset of atrial fibrillation
A soft low pitched rumbling mid to late diastolic murmur seen severe AR
Austin flint murmur
“Austin Rint murmur”
AR-AR
A high pitched diastolic decrescending blowing murmur along the left sternal border results from dilation of the pulmonary valve ring and occurs in mitral valve disease and severe pulmonary hypertension
Graham steell murmur
Seen MVD and PR
Mitral commissurotomy indication
symptomatic NYHA II - IV, isolated severe MS orifice =< 1 cm2/m2 BSA or < 1.5 cm2 in normal sized adults
Hyperplastic disorder affecting medium size and small arteries, predominantly among females
Fibromuscular dysplasia
Arteries commonly affected in Fibromuscular dysplase
More common: Renal and carotid arteries
Less common: iliac, subclavian (most common limb artery affected = iliac arteries)
Angiographic finding of Fibromuscular dysplasia
String of beads
Tx: PTA, surgical reconstruction
Inflammatory occlusive vascular disorder of small and medium sized arteries and veins in the distal upper and lower extremities
Thromboangitis Obliterans (Buerger’s disease)
Pulseless disease that may involve descending thoracic and abdominal aorta and what is the treatment?
Takayasu’s arteritis
Tx: Acute stage: glucocorticoids and immunosuppressives
Critical stenotic artery: surgical bypass or endovascular intervention
Pathology of thromboangiitis obliterans on disease progression
Initial stage: PMN migration infiltrating walls of the small and medium-sized arteries and veins
Disease progression: PMNs replaced by mononuclear cells, fibroblasts and giant cells
Later stages: Perivascular fibrosis and recanalization
Triad of Thromboangiitis obliterans:
Claudication of affected extremity, Raynauds phenomenon, migratory superfical vein, thrombophlebitis
In Acute limb ischemia, what isbthe most frequent site of thrombosis in situ:
Atherosclerotic vessel at site of an atherosclerotic plaque/aneurysm, arterial bypass grafts
When to do Amputation in Acute limb ischemia?
Done if the limb is not viable, loss of sensation, paralysis and the absence of doppler detected blood flow in both arteries and veins
Screening test for Primary Aldosreronism
PA/PRA RATIO >30:1 + plasma aldosterone concentration > 555pmol/L (>20ng/dL): 90%
Some antihypertensive medications can affect ratio (must stop drugs 4-6 weeks before test)
