Clinical methods and pathophysiology 69 Ambulatory blood pressure monitoring early after acute myocardial infarction: development of a new prognostic index Lanfranco Antonini, Vincenzo Pasceri, Salvatore Greco, Furio Colivicchi, Solferina Malfatti, Sergio Pede, Vincenzo Guido, Amir Kol and Massimo Santini Objectives The aim of our study was to assess the possible role of a prognostic index based on ambulatory blood pressure monitoring in a large cohort of patients with recent myocardial infarction. Methods The study population included 1335 consecutive patients admitted for ST elevation myocardial infarction and discharged alive from 48 Italian hospitals participating in the multicentric IMPRESSIVE (Infarto Miocardico, Pressione arteriosa e frequenza cardiaca. Studio Italiano di Valutazione Epidemiologica) study. Ambulatory blood pressure monitoring was performed 3 weeks after discharge, with a clinical follow-up of 12 months. End-points included cardiac death and new admission for heart failure. A prognostic index was obtained from the ambulatory blood pressure monitoring variables according to the formula: (220 – age) – mean 24 h heart rate (m24hHR) + mean 24 h diastolic blood pressure (m24hDBP). Results Among many potential predictors only left- ventricular ejection fraction, creatinine levels, Killip class and the prognostic index were independently associated with events during the follow-up. In particular, higher values of the prognostic index were associated with a lower incidence of events, with an odds ratio of 0.958 (95% confidence intervals 0.943–0.974) and a 4% reduction in risk for each point of the prognostic index. Overall incidence of cardiac events was 6-fold higher in patients within the lowest quartile of the prognostic index ( r 148) compared with the other three quartiles (12 vs. 2, 1.4 and 2% respectively in the other three quartiles; P < 0.0001). Conclusions A simple prognostic index based on ambulatory blood pressure monitoring and age may be a useful tool in predicting cardiac death and heart failure in patients with recent myocardial infarction. Blood Press Monit 12:69–74  c 2007 Lippincott Williams & Wilkins. Blood Pressure Monitoring 2007, 12:69–74 Keywords: ambulatory blood pressure monitoring, heart failure, myocardial infarction, prognostic index Cardiovascular Department, San Filippo Neri Hospital, Rome, Italy Correspondence to Dr Lanfranco Antonini, MD, Via Anneo Lucano 26, 00136 Rome, Italy Tel: + 39 0635343449 330652414; fax: + 39 0633062516; e-mail: Lanfranco.Antonini@libero.it Received 9 March 2006 Revised 21 September 2006 Accepted 22 September 2006 Introduction The predictive value of low systolic blood pressure (SBP) for cardiovascular death and heart failure in the acute phase of myocardial infarction (MI) is well known [1]. The possible prognostic role of monitoring of SBP and diastolic blood pressure (DBP) in the early weeks after an MI is, however, unknown. In an earlier preliminary study [2], we used ambulatory blood pressure monitoring (ABPM) to define the trend of blood-pressure values and heart rate early after an acute MI and correlated these values with subsequent cardio- vascular events. We found that mean heart rate during 24 h (m24hHR) and mean 24 h DBP (m24hDBP) were independent predictors for cardiac death and heart failure. Thus, we analyzed ABPM performed in a large multicentric prospective study in patients surviving after acute ST elevation MI. A prognostic index (PI) based on the independent variables was developed accord- ing to the formula (220 – age) – m24hHR + m24hDBP. This PI could provide a simple numeric value to identify high-risk populations. Methods The study population included 1335 patients (1057 men, 278 women, mean age 61.7 ± 11.5 years) consecutively admitted and discharged alive from the 48 cardiology wards of Italian hospitals participating in the IMPRESS- IVE study (Infarto Miocardico, Pressione arteriosa e frequenza cardiaca. Studio Italiano di Valutazione Epide- miologica) during a 12-month period (January–December 1998) after an acute ST-segment elevation MI (STEMI). Exclusion criteria in this study were permanent arrhyth- mias, constant-paced rhythm, inability of the patient to follow the study protocol and relevant comorbidities with a life expectancy of less than 12 months. The study was approved by local ethics committees, and all patients gave informed consent to participate in the study. 1359-5237  c 2007 Lippincott Williams & Wilkins