Prognostic Value of Left and Right Ventricle Myocardial Performance Indices and Introduction of a New Combined Myocardial Performance Index of Both Ventricles in Left Inferior ST Segment Elevated Myocardial Infarction

Research Article

Austin J Clin Cardiolog. 2014;1(3): 1022.

Prognostic Value of Left and Right Ventricle Myocardial Performance Indices and Introduction of a New Combined Myocardial Performance Index of Both Ventricles in Left Inferior ST Segment Elevated Myocardial Infarction

Hayrapetyan HG1*, Adamyan KG2 and Arakelyan IA1

1Department of Urgent Cardiology of Erebouni Medical Centre, Armenia

2Department of Myocardial Infarction of Institute of Cardiology, Armenia

*Corresponding author: Hayrapetyan HG, Department of Urgent Cardiology of Erebouni Medical Centre, 14 Titogradyan Street, Yerevan 0087, Republic of Armenia

Received: April 10, 2014; Accepted: May 26, 2014; Published: May 29, 2014


The study aimed to evaluate the prognostic role of combined myocardial performance index of both ventricles in comparison with the Left Index of Myocardial Performance (LIMP) and/or Right Index of Myocardial Performance (RIMP) for early and late cardiac events in Primary Left Ventricular (LV) inferior ST-Segment Elevated Myocardial Infarction (STEMI). The study sample was composed of 221 patients (age 58.4±5.5 years, 189 men) with primary LV inferior STEMI. All patients underwent Doppler echocardiography and ascertained one year follow-up. Cases of hospital cardiac deaths; Acute Cardiac Complications (ACCs) - Ventricular Extrasystoly ≥ Lown III° (VE), sino-atrial or atrio-ventricular Heart Block of II-IIIO (HB), Supraventricular Tachyarrhythmia (SVT), and Cardiogenic Shock (CS); 1 year post-hospital cardiac deaths; and 1 year cardiac re-hospitalization were analyzed. LIMP was a significant explanatory factor for CS, 1-year cardiac death and 1-year re-hospitalization while RIMP predicted hospital cardiac death and all ACCs. Furthermore, [LIMP+ RIMP] ≥1.00 established its powerful predictive value in all study outcomes - hospital cardiac death, all ACCs (p<0.01 for all cases), 1-year cardiac death and re-hospitalization (p<0.001 for both cases). Combined LIMP and RIMP is shown to be a stronger prognostic factor than LIMP or RIMP alone for all the selected study outcomes. We suggest using this newly established index of [LIMP+ RIMP] ≥1.00 in identifying primary LV inferior STEMI high-risk patients for both early and late clinical outcomes.

Keywords: Myocardial performance index; Inferior STEMI; Prognosis


ACCs - Acute Cardiac Complications; AMI - Acute Myocardial Infarction; CS - Cardiogenic Shock; DMI - Doppler Myocardial Imaging; FAC - Fractional Area Change; HB - sino-atrial or atrio-ventricular Heart Block of II-III°; LIMP - Left Index of Myocardial Performance; LV - Left Ventricle; MPI - Myocardial Performance Index; ORadj - Adjusted Odds Ratios; RIMP - Right Index of Myocardial Performance; RV - Right Ventricle; STEMI - ST-Segment Elevated Myocardial Infarction; SVT - Supraventricular Tachyarrhythmia; VE - Ventricular Extrasystoly ≥ Lown III°


The Doppler-derived myocardial performance index (MPI), also known as the Tei index, is a relatively new measure of combined systolic and diastolic functions [1]. It is based on the relationship between ejection and non-ejection work of the heart. MPI is simple, noninvasive, easy to estimate and reproducible.

Several studies have recently shown that Left Index of Myocardial Performance (LIMP) has a prognostic value for clinical outcomes in Acute Myocardial Infarction (AMI) and many authors underlined usefulness of this index for practical implementation, especially, for risk stratification purposes [2]. Particularly, LIMP has been shown to be a useful, sensitive, and reproducible indicator for myocardial dysfunction in many clinical settings in distinguishing patients with a poor in-hospital outcome, and its value as an independent predictor of cardiac events during hospitalization [3-5]. Also, it has been demonstrated that LIMP predicts LV remodeling [6] and improvement of LIMP closely reflects intrinsic improvement of cardiac function [7]. Further, in late phase of AMI the index has shown prognostic value regarding death, heart failure, and new cardiac events [8,9].

Recent studies showed that in patients with Left Ventricular (LV) inferior STEMI, involvement of Right Ventricle (RV) in AMI can significantly change the clinical course, which is associated with development of RV dysfunction and acute cardiac arrhythmias and blocks. Mehta showed in a meta-analysis that patients with RV involvement in inferior AMI were at increased risk of adverse events and demonstrated that RV involvement is not due to more extensive infarction of the LV [10]. In post-AMI patients with LV dysfunction, Zornoff and Anavekar confirmed that RV function is weakly correlated with LV function and demonstrated that RV function quantified with RV Fractional Area Change (FAC) was independently associated with an increased risk of mortality and heart failure [11].

Since LV inferior STEMI is a unique pathology with possible involvement of RV in AMI leading to RV dysfunction and worsen clinical outcomes, it would be reasonable to assess function of not only LV, but also RV in such patients.

The purpose of the current study was to test prognostic importance of a combination of LIMP (as a measurement of LV dysfunction) and RIMP (as a measurement of RV dysfunction) in comparison with LIMP or RIMP used individually in patients with primary LV inferior STEMI. As a specific objective, this study evaluates the ability of LIMP, RIMP and the sum of LIMP and RIMP to independently predict early (hospital) and late (1-year) cardiac morbidity and mortality in patients with LV inferior STEMI.

Materials and Methods

This study was approved by the local Ethics Committee of Yerevan State Medical University and all subjects were fully informed about the study and provided an informed consent to voluntary participate in the study.

Study Sample

236 patients with primary LV inferior STEMI who underwent Doppler Myocardial Imaging (DMI) at the Department of Urgent Cardiology of Erebouni Medical Centre, Yerevan in 1998-2011 were considered for study recruitment and 221 met eligibility criteria. The reasons for non-inclusion were the following diseases and conditions detected by history or typical symptoms that could bias the study findings - permanent or persistent atrial fibrillation; congenital heart diseases; significant rheumatic aortal and/or mitral stenos?s; permanent pacemaker; strokes; diseases with severe pulmonary hypertension; chronic kidney diseases; blood diseases and anemia and other metabolic and oncological diseases.

Of the 221 study patients, 189 (85.5%) were male and 32 (14.5%) were female. Age range was 38 to 72 years (mean 58.2±4.5 years). A careful medical history for each of 221 enrolled patients was thoroughly assessed and a complete physical and standard instrumental and lab examination was performed on all the study subjects.

With regard to the diagnosis of LV inferior STEMI and treatment strategy, patients were treated according to the institutional AMI STEMI management algorithm based on the current evidence-based treatment guidelines [12,13]. 34 (15.4%) study subjects underwent primary Percutaneous Coronary Intervention (PCI) and the remaining 187 (84.6 %) received conservative treatment including 15 who received thrombolytic treatment.

Based on LIMP, RIMP and [LIMP+ RIMP] values, all 221 patients were categorized into the following groups:

There were no statistically significant differences in the demographic characteristics and the preexisting morbidity among the study participants in the different study groups (assessed variables were age, Arterial Hypertension (AH), Diabetes Mellitus (DM), and Chronic Obstructive Pulmonary Disease (COPD)). Table 1 summarizes the baseline clinical characteristics of the study sample by defined groups.