Chapter 3 ST-Elevation Myocardial Infarction
5 Echocardiography should be used to evaluate
mechanical complications unless these are assessed
by invasive measures. (Level of Evidence: C)
Class IIa
1 Pulmonary artery catheter monitoring can be
useful for the management of STEMI patients with
cardiogenic shock. (Level of Evidence: C)
2 Early revascularization, either PCI or CABG, is
reasonable for selected patients 75 years or older
with ST elevation or LBBB who develop shock
within 36 hours of MI and are suitable for revascu-
larization that can be performed within 18 hours of
shock. Patients with good prior functional status
who agree to invasive care may be selected for such
an invasive strategy. (Level of Evidence: B)
- Right ventricular infarction
Class I
1 Patients with inferior STEMI and hemodynamic
compromise should be assessed with a right precor-
dial V4R lead to detect ST-segment elevation and an
echocardiogram to screen for RV infarction. (See
the ACC/AHA/ASE 2003 Guideline Update for the
Clinical Application of Echocardiography.) (Level of
Evidence: B)
2 The following principles apply to therapy of
patients with STEMI and RV infarction and isch-
emic dysfunction:
a. Early reperfusion should be achieved if possi-
ble. (Level of Evidence: C)
b. AV synchrony should be achieved, and brady-
cardia should be corrected. (Level of Evidence: C)
c. RV preload should be optimized, which usually
requires initial volume challenge in patients with
hemodynamic instability provided the jugular venous
pressure is normal or low. (Level of Evidence: C)
d. RV afterload should be optimized, which
usually requires therapy for concomitant LV dys-
function. (Level of Evidence: C)
e. Inotropic support should be used for hemody-
namic instability not responsive to volume chal-
lenge. (Level of Evidence: C)
Class IIa
After infarction that leads to clinically signifi cant RV
dysfunction, it is reasonable to delay CABG surgery
for 4 weeks to allow recovery of contractile perfor-
mance. (Level of Evidence: C)
- Mechanical causes of heart failure/
low-output syndrome
a. Diagnosis
Mechanical defects, when they occur, usually present
within the fi rst week after STEMI. On physical
examination, the presence of a new cardiac murmur
indicates the possibility of either a VSR or MR. Left
ventricular free-wall rupture is typically heralded by
chest pain and ECG ST-T-wave changes, with rapid
progression to hemodynamic collapse and electro-
mechanical dissociation.
b. Mitral valve regurgitation
Class I
1 Patients with acute papillary muscle rupture should
be considered for urgent cardiac surgical repair, unless
further support is considered futile because of the
patient’s wishes or contraindications/unsuitability
for further invasive care. (Level of Evidence: B)
2 CABG surgery should be undertaken at the same
time as mitral valve surgery. (Level of Evidence: B)
c. Ventricular septal rupture after STEMI
Class I
1 Patients with STEMI complicated by the develop-
ment of a VSR should be considered for urgent
cardiac surgical repair, unless further support is
considered futile because of the patient’s wishes or
contraindications/unsuitability for further invasive
care. (Level of Evidence: B)
2 CABG should be undertaken at the same time as
repair of the VSR. (Level of Evidence: B)
d. Left ventricular free-wall rupture
Class I
1 Patients with free-wall rupture should be consid-
ered for urgent cardiac surgical repair, unless further
support is considered futile because of the patient’s
wishes or contraindications/unsuitability for further
invasive care. (Level of Evidence: B)
2 CABG should be undertaken at the same time as
repair of free-wall rupture. (Level of Evidence: C)
e. Left ventricular aneurysm
Class IIa
It is reasonable that patients with STEMI who
develop a ventricular aneurysm associated with
intractable ventricular tachyarrhythmias and/or
pump failure unresponsive to medical and catheter-
based therapy be considered for LV aneurysmec-
tomy and CABG surgery. (Level of Evidence: B)