EKG RoundsMark Bromley PGY3

Objectives Identify classic ECG findings of PE

Understand the pathophysiologic basis

Discuss clinical utility

What are the Classic Findings of PE on ECG?

Case 1A 54 year-old man

Presents with sudden dyspnea

Hx of recent orthopedic surgery

OE: moderate distress dyspnea HR115 RR 36 O2 sats: 92% BP 165/90 His exam was unremarkable except for a casted L leg

Case 1

FindingsTachycardia

Rightward axis

S1Q3T3

Simultanoeus T-wave inversion in inferior & anteroseptal leads

Incomplete RBBB

What are the Classic Findings of PE on ECG?

“Classic” ECG AbnormalitiesSinus Tachycardia

RV strain pattern T wave inversions in V1-V4

Rightward axis deviation

Incomplete RBBB

P pulmonalae

S1Q3 or S1Q3T3 pattern

Acute cor pulomnale: S1Q3T3 pattern, right axis deviation, and RBBB.

These changes, particularly in combination, are suggestive but not diagnostic of PE

Even pts with massive PE may have only mild, nonspecific ECG changes

In pulmonary embolus,…what is the most common ECG pattern?

Normal ECGCompletely normal

Sinus rhythm between 60-100 bpm

Normal conduction

Normal axis

Normal P wave, QRS complex, and ST segment/T wave morphologies

An entirely normal ECG is found in10% to 25%*

*(Panos, 1988; Hubloue, 1996)

What is the most common ECG abnormality?

Sinus Tachycardia

comment on the conduction

Right Sided StrainIncomplete RBBB

right-sided heart pressures leads to ventricular afterload

Results in right-sided myocardial wall tension

The RV is not able to withstand such pressures

…it rapidly dilates

chamber size and eventual contractile dysfunction

Case 229-year-old woman

Presents with shortness of breath

History: 8 weeks pregnant

On exam: Visibly distressed HR 110 RR 32 O2 Sat 91% on 5 L BP 80/40

Case 2

FindingsRate 120

Incomplete RBBB

T wave abnormality

29 F 19 weeks gestation. Presents SOB.

2 hours later

P pulmonalaeAssociated with RA enlargement

Incidence: 2% - 30%

Case 369-year-old man

Presents with shortness of breath

History of diabetes and hypertension

On exam: Comfortable and alert. HR 110 RR 32 O2 Sat 97% on 5 L BP 163/107 Exam was otherwise unremarkable

Case 3

Case 3 - findingsTachycardia

R axis deviation

Incomplete RBBB

S1Q3T3

Simultaneous inversion of T waves in Inferior and anteroseptal leads

p pulmonalae

Ischemia and InfarctionCO compromises both systemic and coronary

perfusion

wall tension

Systemic hypotension Ischemia and infarction

As right-sided ventricular dysfunction worsens, RV infarction and circulatory collapse may occur

Right Axis DeviationRV enlargement

Negative deflection of lead I

Positive deflection of V6

Left axis deviation – more common (related to underlying dz)

When control for underlying disease – equal incidence

(Nielsen, 1989)

McGinn-White Pattern S1Q3T3

First described in 1935 – 7 pts with massive PE

Since numerous authors have refuted the usefulness

Still classically linked to PE

Q: Give a differential diagnosis for S1Q3T3. PTx Embolism

AIR, FAT, PE Cor pulmonalea

Severe Pneumonia Neoplastic disease

Diagnostic value of ECGMany studies have been done in patients with confirmed PE

Diagnostic value of ECG can only be determined by applying it to patients with suspected PE

…then determine if the test is predictive of PE

Pts presenting to ED – R/O PE

ECGs were obtained on 189/212 patients

analyzed for 28 features thought to be associated with PE

Only tachycardia and incomplete RBBB were significantly more frequent in patients with PE than those without PE

S1Q3T3 not predictive

PrognosisWhat findings were more frequent in pts with fatal outcome?

Atrial arrhythmias Complete right bundle branch block Peripheral low voltage Pseudoinfarction pattern (Q waves) in leads III and aVF STΔ’s (or ) in left precordial leads

29% of pts who exhibited ≥ 1 of these abnormalities did not survive to hospital discharge

11% of the patients without a pathological ECG

(Giebel et al., 2005)

Take Home PointsECG is not a sensitive or specific test for PE

ECG changes are transient

Most common ECG finding – normal

Most common ECG abnormality – sinus tach

Value of ECG in PE Assessing other etiologies Prognostic value

References Panos R J, Barish RA, Whye DW, et al: The electrocardio-

graphic manifestations of pulmonary embolism. J Emerg Med 1988; 6:301-7

Hubloue I, Schoors D, Diltoer M, et al: Early electrocardio- graphic signs in acute massive pulmonary embolism. Eur J Emerg Med 1996; 3:199-204

Akula et al. Right-sided EKG in pulmonary embolism. Journal of the National Medical Association (2003).

Nielsen F, Lund O, Ronne K, et al: Changing electrocardio- graphic findings in pulmonary embolism in relation to vascular ob- struction. Cardiol 1989;76:274-284

Geibel et al. Prognostic value of the ECG on admission in patients with acute major pulmonary embolism. European Respiratory Journal (2005)

Right Sided Chest Leads Increase the sensitivity of ECG

Very small study looked prospectively at 100 pts

Results: PE present in 20pts Standard ECG - findings present in 80% Right-sided ECG – findings present in 100% qr or qs in V4R, V5R, V6R, increased sensitivity

(Akula, 2003)

Case 418 year female

Presents with syncope

History: OCP

OE: looks well HR 102 RR 17 BP 120/76 O2 sats 94% Otherwise unremarkable

Case 4