Emergency Department ECG:
* Patient has history of CABG. Right side ECG shows ST elevation in V4R indicating possible R ventricular involvement
Cardiac Cath Report:
LMCA: Patent, gives rise to the LAD and LCX.
LAD: 100% mid occlusion. Diagonal with long 80% stenosis. Distal AD fed by LIMA and is patent to the apex. No competitive flow noted to any graft.
LCX: Proximal 80% stenosis, large OM1 with 85% stenosis, ongoing LCX is small and occluded. No competitive flow noted to any graft.
RCA: Large, dominant, 95% mid stenosis with thrombus, TIMI 2.5 flow, distal RCA with 50% lesion beyond site of plaque rupture, patent right PDA.
PLAN: Successful stent placement in mid RCA
- Right side MI
- Complicates 40% of inferior MIs
- Right ventricle is preload dependent which may lead to hypotension if Nitroglycerin is administered. Treat with IV fluids and rapid transport.
- Right side ECG
- A complete set of right-sided leads is obtained by placing leads V1-6 in a mirror-image position on the right side of the chest (see diagram, below).
- It may be simpler to leave V1 and V2 in their usual positions and just transfer leads V3-6 to the right side of the chest (i.e. V3R to V6R).
- The most useful lead is V4R, which is obtained by placing the V4 electrode in the 5th right intercostal space in the midclavicular line. ST elevation in V4R has a sensitivity of 88%, specificity of 78% and diagnostic accuracy of 83% in the diagnosis of RV MI
- Inferior MI
- 40-50% of all myocardial infarctions.
- more favorable prognosis than anterior myocardial infarction
- Up to 40% of patients with an inferior STEMI will have a concomitant right ventricular infarction. These patients may develop severe hypotension in response to nitrates and generally have a worse prognosis.
- Confirmed with Right sided ECG, Elevation in V4R
- Up to 20% of patients with inferior STEMI will develop significant bradycardia due to second- or third-degree AV block. These patients have an increased in-hospital mortality (>20%).
- ECG findings
- ST elevation in leads II, III and aVF
- Reciprocal ST depression in aVL (± lead I)
- RCA (80%): Elevation in III > II, Reciprocal depression in I
- LCx (20%): Elevation in III = II, No reciprocal depression in I
Right Side ECG: