ECGs by diagnosis

Arrythmias

See Cards: Arrythmias (DDX)

MI

-T wave usu tracks w/ the QRS, thus if QRS primarily negative, twi is not necessarily abnl (nl twi in V1).

-ST elevation non-specific, also w/ LVH & strain, LBBB, CA spasm, pericarditis, "early repol", hyperK, dig/TCA's, CVA, Vent. aneurysm, hypothermia.

-Non-transmural: ST dep at least 1.0mm, twi.

-II, II, AVF for inf. MI

-V1-3 for anteroseptal inf.

-I, AVL, V4-6 for lat. wall inf.

-V1 or V2-6 anterolat.

-Large R and ST depression in V1-V2= POST. INFARCT! Post MI usu seen w/ inf MI b/c RCA supplies both in 90% of pts!

-Pts w/ inf. infarction +/or post wall mi often also have RV mi, need R sided leads!!

-STE >/= 1mm in V3R or V4R suggest RV MI!

-STE > 2wks= poss vent aneurysm!

-STE in avR and avL = LMA stenosis

-STE in avR and V1 = LAD or LMA stenosis

-if STE > 1.5 mm in avR pt has 75% mortality from AMI --> activate cath lab (unless pt is in SVT, then STE is allowed)

Infarct notes:

-inf wall: recip. In 1 and AVl. Downward sloping ST in AVl is often first sign.

-Any ST depression in V1 to V3 in a LBBB is pathological and suggestive of a post. Wall MI.

-Poor r waves progression-no r's by V4

-persistent t-wave elevation 6 wks post mi-vent. Anyeursm.anteroseptal with biphasic/inverted t wave.

Pericarditis

-Stage I: ST elevated in precordial leads, esp. V5-6 & I-II. Isoelectric or depressed ST in V1. PR depression in II, AVF, V4-6.

-Stage II: ST returning to baseline. T wave amplitude decreases.

-Stage III: ST isoelectric. TWI where prior STE.

-Stage IV: Resolution of T wave changes.

-Also ST:T ratio >0.25 in V6

(Depressed PR, Diffuse ST elevation, Scooping upwardly concave ST segments, Notching at the end of the QRS)

HyperK

-5.5-6.6 -> tall peaked T, deep S in I and V6, QRS nml

-7.0-8.0 -> QRS widens, slurred initial and term QRS, ST elevation, low wide P's, AV blocks, SA arrest, bradycardia.

->8.0 -> widened QRS, Vfib, asystole.

HypoK

-3.0-3.5 no change or flat T' sand U's in V2-3, QT interval and QRS nml.

-2.7-3.0 U taller, T smaller, esp. V2-3

-<2.6 ECG change includes tall U's, QT and QRS wnl.

HyperCa

-Increased QRS duration (slight)

-ST short or absent

-Short corrected QT.

-PR long

HypoCa

-slight decrease in QRS.

-ST and corrected QT long

-PR short.

-T's flat to inverted.

CNS

-SAH, IC bleed, stroke, can see diffuse wide deep, blunted inverted T's. and QT prolonged

Pacemakers

-Should be in the apex of R vent.

-ECG should mimic LBBB, w/ L axis.

PE

-S1Q3T3

(good specificity, poor sensitiviy)

Source

DONALDSON 17/09 (Adapted from Niemann/Lampe)