The Rhythm Of Life A DEDICATION TO PRESERVATION The First Sign Of Life

Understanding Normal

Understanding Axis & The Acute MI Find The Axis Find The Axis Normal Axis Left Axis Right Axis ERAD 1. Find the biphasic QRS. 2. Find the lead perpendicular to the biphasic lead. 3. Axis will be within a few degrees of the perpendicular lead.

Axis & S-T Changes ∑S-T changes will be the most obvious in the direction of the axis it travels ∑S-T changes will be diminished in the leads perpendicular to the mean axis ∑Reciprocal changes are the best evidence of EKG changes in low voltage leads ( Lateral) ∑The mean axis will deviate around area of infarction Obvious STEMI MI?

Subtle Inferior Wall MI 70 YR MALE W/ CP

BP 134 / 80 HR56 R 20 R SP02 98%

‹ Sinus Rhythm w/ R axis of 26 ‹ Poor septal R wave progression ‹ inversion in AVL with terminal S wave distortion ‹ Hyper acute T waves in lead 3 in proportion to QRS ‹ Abnormal disposition heart rate Right Coronary Artery

LAD Coronary Artery

Occlusion to RCA commonly results in an abnormal SA node and AV conduction 5 MINUTES LATER ∑ 49 YR MALE PT W/ CHEST PAIN 6/10 ∑ STARTED THIS MORNING ∑ ASA ADMINISTERED PTA ∑ 206 / 102 HR72 R18 R SP0297

‹ SINUS RHYTHM ‹ LEFT AXIS DEVIATION ‹ S-T DEPRESSION IN LEAD 3 ‹ INVERTED T WAVE IN LEAD 3 ‹ SUBTLE LATERAL S-T ELEVATION Subtle Inferior Wall MI Obvious Inferior Wall MI What do we see? Right Coronary Artery

LAD Coronary Artery

Occlusion to LAD commonly results in a & left axis deviation Red Flags of ECG Interpretation 52 YR MALE PT

∑ Chest pain which resolved after ASA & 2 Nitro ∑ Admitted to the floor for 36 hours Wellens Sign 1. Sudden LAD occlusion with associated symptoms. 2. LAD is reperfused ( due to spontaneous clot lysis or prehospital intervention). ST elevation resolves and T waves become biphasic. 3. If the LAD remains open the T waves will become deeply inverted. 4. Coronary perfusion remains unstable and can occlude at anytime. The first EKG sign of re- occlusion is normalization of the T waves (Pseudo Normalization). AB Meet Alice De Winters S-T T wave ∑Anterior STEMI equivalent that presents without obvious S-T elevation ∑Diagnostic key is S-T depression and peaked T waves in the precordial leads ∑Often seen with small S-T elevation in AVR ∑Often under-recognized by clinician's ∑Indicates possible occlusion of the LAD MI? SGARBOSSA CRITERIA 98% Specific 20% Sensitive Modified Sgarbossa Criteria

1. At least one lead with concordant STE

2. At least one lead of V1-V3 with concordant ST depression

3. Proportionally excessively discordant ST elevation in V1-V4, as defined by an ST/S ratio of equal to or more than 0.25 and at least 1 mm of STE. STE/S WAVE 100% Sensitive

88% Specific How do we retain all this? ∑Desire ∑Utilizing FOAMed ∑Exposure ∑Developing a culture of learning