Sections View Full Chapter Figures Tables Videos Annotate Full Chapter Figures Tables Videos Supplementary Content +++ KEY FEATURES +++ ESSENTIALS OF DIAGNOSIS ++ Symptoms consistent with acute myocardial infarction (MI) ECG changes of acute inferior or posterior ST-segment elevation MI with ≥ 1 mm ST-segment elevation in V3R or V4R Elevated cardiac biomarkers Echocardiographic evidence of right ventricular wall motion abnormalities Hypotension and jugular venous distention with clear lung fields commonly observed In acute inferoposterior MI, a mean right atrial to pulmonary wedge pressure ratio of ≥ 0.8 +++ GENERAL CONSIDERATIONS ++ Right ventricular (RV) involvement in acute inferior MI is common Hemodynamically significant RV dysfunction is uncommon Of patients with acute inferoposterior MI, 20% may have hemodynamically significant RV involvement RV becomes noncontractile Cardiac output may be maintained in the initial phases by passive flow through the RV Right-sided heart pressures are elevated Left heart pressures are normal or minimally increased +++ CLINICAL PRESENTATION +++ SYMPTOMS AND SIGNS ++ Chest pain and symptoms of MI +++ PHYSICAL EXAM FINDINGS ++ Elevated jugular venous distention Hypotension Cold and clammy extremities Cardiogenic shock Steep jugular venous y descent Kussmaul sign +++ DIFFERENTIAL DIAGNOSIS ++ Hypotension from other causes with inferoposterior MI Pericarditis Pulmonary embolus Aortic dissection +++ DIAGNOSTIC EVALUATION +++ LABORATORY TESTS ++ CBC Metabolic panel Arterial blood gases Chest x-ray: usually shows clear lung fields Cardiac troponins I or T Brain natriuretic peptide levels +++ ELECTROCARDIOGRAPHY ++ Evidence of acute inferior or posterior MI with ST elevation Shows ST elevation with right-sided chest leads V3R and V4R +++ IMAGING STUDIES ++ Echocardiogram: – Shows RV regional wall motion abnormalities – May show depressed RV systolic function +++ DIAGNOSTIC PROCEDURES ++ Right heart catheterization shows characteristic hemodynamic findings: steep y descent of right atrial pressure and ratio of mean right atrial to pulmonary capillary wedge pressure of > 0.8 Coronary angiogram usually shows occlusion of the right coronary artery or a dominant circumflex coronary artery +++ TREATMENT +++ CARDIOLOGY REFERRAL ++ Patients with acute MI should be managed in consultation with a cardiologist Once hypotension occurs, the care should be transferred to a cardiologist +++ HOSPITALIZATION CRITERIA ++ All acute MI patients have to be hospitalized Patients must be managed in a cardiac intensive care unit +++ MEDICATIONS ++ Immediate coronary reperfusion IV fluids if left or right atrial pressure is low IV positive inotropic agents such as dobutamine to maintain blood pressure Avoid diuretics and vasodilators Other treatment similar to that for acute ST-segment elevation MI +++ THERAPEUTIC PROCEDURES ++ Percutaneous coronary ... Your Access profile is currently affiliated with [InstitutionA] and is in the process of switching affiliations to [InstitutionB]. Please select how you would like to proceed. Keep the current affiliation with [InstitutionA] and continue with the Access profile sign in process Switch affiliation to [InstitutionB] and continue with the Access profile sign in process Get Free Access Through Your Institution Learn how to see if your library subscribes to McGraw Hill Medical products. Subscribe: Institutional or Individual Sign In Error: Incorrect UserName or Password Username Error: Please enter User Name Password Error: Please enter Password Sign in Forgot Password? Forgot Username? Download the Access App: iOS | Android Sign in via OpenAthens Sign in via Shibboleth You already have access! Please proceed to your institution's subscription. Create a free profile for additional features.