Impact of right ventricular involvement on mortality and morbidity in patients with inferior myocardial infarction.

OBJECTIVES We sought to evaluate the prognostic impact of right ventricular (RV) myocardial involvement in patients with inferior myocardial infarction (MI). BACKGROUND There is uncertainty regarding the risk of major complications in patients with inferior MI complicated by RV myocardial involvement. Whether these complications are related to RV myocardial involvement itself or simply to the extent of infarction involving the left ventricle (LV) is also unknown. METHODS We examined the incidence of death and mechanical and electrical complications in patients with (n = 491) and without (n = 638) RV myocardial involvement and in patients with anterior MI (n = 971) in an analysis from the Collaborative Organization for RheothRx Evaluation (CORE) trial. Left ventricular infarct size was assessed by technetium-99m-sestamibi single-photon emission computed tomography and peak creatine kinase, and LV function was assessed by radionuclide angiography. We also performed a meta-analysis in which we pooled the results of our study with previous smaller studies addressing the same question. RESULTS Six-month mortality was 7.8% in inferior MI compared with 13.2% in anterior MI. Among patients with inferior MI, serious arrhythmias were significantly more common in patients with RV myocardial involvement who also had a trend toward higher mortality, pump failure and mechanical complications. However, this was not associated with a difference in LV infarct size or function. A meta-analysis of six studies (n = 1,198) confirmed that RV myocardial involvement was associated with an increased risk of death (odds ratio [OR] 3.2, 95% confidence interval [CI] 2.4 to 4.1), shock (OR 3.2, 95% CI 2.4 to 3.5), ventricular tachycardia or fibrillation (OR 2.7, 95% CI 2.1 to 3.5) and atrioventricular block (OR 3.4, 95% CI 2.7 to 4.2). CONCLUSIONS Patients with inferior MI who also have RV myocardial involvement are at increased risk of death, shock and arrhythmias. This increased risk is related to the presence of RV myocardial involvement itself rather than the extent of LV myocardial damage.

[1]  W. O’Neill,et al.  Effect of reperfusion on biventricular function and survival after right ventricular infarction. , 1998, The New England journal of medicine.

[2]  Effects of RheothRx on mortality, morbidity, left ventricular function, and infarct size in patients with acute myocardial infarction. Collaborative Organization for RheothRx Evaluation (CORE). , 1997, Circulation.

[3]  P. Brugada,et al.  Value of electrocardiogram in diagnosing right ventricular involvement in patients with an acute inferior wall myocardial infarction. , 1983, British heart journal.

[4]  J. Alpert,et al.  Cardiogenic shock after acute myocardial infarction: Incidence and Mortality from a Community-Wide Perspective, 1975 to 1988 , 1991 .

[5]  M. Olschewski,et al.  Right ventricular infarction as an independent predictor of prognosis after acute inferior myocardial infarction. , 1993, The New England journal of medicine.

[6]  D. Berman,et al.  Scintigraphically detected predominant right ventricular dysfunction in acute myocardial infarction: clinical and hemodynamic correlates and implications for therapy and prognosis. , 1985, Journal of the American College of Cardiology.

[7]  R. Peto,et al.  Beta blockade during and after myocardial infarction: an overview of the randomized trials. , 1985, Progress in cardiovascular diseases.

[8]  D. Berman,et al.  Variable spectrum and prognostic implications of left and right ventricular ejection fractions in patients with and without clinical heart failure after acute myocardial infarction. , 1986, The American journal of cardiology.

[9]  J. López-Sendón,et al.  In-hospital outcome of elderly patients with acute inferior myocardial infarction and right ventricular involvement. , 1997, Circulation.

[10]  K. Wegscheider,et al.  Effects of thrombolytic therapy in acute inferior myocardial infarction with or without right ventricular involvement. HIT-4 Trial Group. Hirudin for Improvement of Thrombolysis. , 1998, Journal of the American College of Cardiology.

[11]  J. Corbett,et al.  Detection of acute right ventricular infarction by right precordial electrocardiography. , 1982, The American journal of cardiology.

[12]  A. Jacobs,et al.  Frequency and significance of right ventricular dysfunction during inferior wall left ventricular myocardial infarction treated with thrombolytic therapy (results from the Thrombolysis in Myocardial Infarction [TIMI] II trial) , 1993 .

[13]  J. Cinca,et al.  Right ventricular infarction: relationships between ST segment elevation in V4R and hemodynamic, scintigraphic, and echocardiographic findings in patients with acute inferior myocardial infarction. , 1981, American heart journal.

[14]  J. W. Kinch,et al.  Right ventricular infarction. , 1994, The New England journal of medicine.

[15]  J. López-Sendón,et al.  Combined effect of age and right ventricular involvement on acute inferior myocardial infarction prognosis. , 1998, Circulation.

[16]  W. Roberts,et al.  Right ventricular infarction complicating left ventricular infarction secondary to coronary heart disease. Frequency, location, associated findings and significance from analysis of 236 necropsy patients with acute or healed myocardial infarction. , 1978, The American journal of cardiology.

[17]  T. Ryan,et al.  Inferior myocardial infarction. High-risk subgroups. , 1990, Circulation.

[18]  P. Brugada,et al.  Right ventricular involvement with acute inferior wall myocardial infarction identifies high risk of developing atrioventricular nodal conduction disturbances. , 1984, American heart journal.