The prognostic role of electrocardiographic left ventricular mass assessment for identifying PCI-treated patients with acute ST-elevation myocardial infarction at high risk of unfavourable outcome.

BACKGROUND: In prognostic terms, evaluation of an ECG recording in acute myocardial infarction (AMI) appears to be inferior to echocardiographic (ECHO) assessment of left ventricular remodelling and the activities of cardiac enzymes and certain hormones. It was our hypothesis that, in the era of interventional treatment of AMI, some ECG parameters are still valid for the purpose of risk stratification. METHODS: A total of 66 consecutive patients with AMI (43 male and 23 female, with a mean age of 61 +/- 11 years) were treated with primary percutaneous coronary intervention (PCI). In each patient ECG and ECHO examinations were performed within 5-7 days of admission for the detection of left ventricular hypertrophy (LVH). In further analysis the following ECG- based LVH parameters were taken into consideration: Sokolov-Lyon voltage duration (SLVd), Cornell voltage duration CVd), 12-lead QRS voltage duration (12QRSVd), their product with QRS duration and an ECG index of left ventricular mass (LVMI(ECG)). Patients were followed for 6 months. The combined end-point included death, infarction, a need for prompt coronary intervention and hospitalization for heart failure. RESULTS: The combined end-point was observed in 16 patients (24.2%). Survival analysis revealed that the most important prognostic factors were associated with a prolongation of the QRS duration. Increased SLVd was found in 43% of the patients with events compared to 14% in those without them (p < 0.01), CVd in 43% vs. 12% (p < 0.05), 12QRSVd in 81% vs. 44% (p < 0.05) and LVMI(ECG) in 75% vs. 26%, p < 0.001). There was no evidence for a difference in Cornell voltage. Univariate logistic regression indicated a 4-fold to 8-fold increase in the risk of events associated with abnormal SLV, SLVd or LVMI(ECG). Multivariate Cox analysis showed that the LVH presence in the ECG, defined as an increased SLVd product or increased LVMI(ECG), was an independent predictor of cardiovascular events after AMI. CONCLUSIONS: In the era of interventional treatment of AMI, the ECG features of left ventricular hypertrophy carry independent significant prognostic information. (Cardiol J 2007; 14: 347-354).

Increased variability of the coupling interval of premature ventricular beats may help to identify high-risk patients with coronary artery disease.

OBJECTIVE: The purpose of this study was to determine the characteristics and predictive value of the variability of coupling interval of ventricular premature beats (VPBs) for cardiac mortality in patients with coronary artery disease (CAD). BACKGROUND: Frequent VPBs have been linked to an increased risk for cardiac death in patients with coronary artery disease. It is unknown whether analysis of coupling interval of VPBs from ambulatory ECG recordings can be used for risk statification in these patients. METHODS: In 78 consecutive symptomatic patients with documented CAD who presented with frequent VPBs (>720/24 h), the analysis of VPBs' coupling interval (SDNV) was performed. Left ventricular function, ventricular arrhythmias and simple measures of heart rate variability were assessed. Mean follow-up was 702+/-329 days. Cardiac mortality was the primary end-point of the study. RESULTS: During follow-up, 14 patients died-11 deaths were cardiac. Left ventricular ejection fraction (LVEF)<40%; no beta-blocker treatment and digoxin use were clinical variables showing a significant association with cardiac mortality. The presence of non-sustained ventricular tachycardia (nsVT), especially if more than five episodes were present; short mean sinus cycle (<750 ms) and SDNV were associated with cardiac deaths. Mean SDNV was 79+/-29 in victims and 63+/-29 in survivors (p<0.05). Univariate Cox regression analysis revealed that the presence of SDNV>80 ms carried a relative risk of 6.7 for cardiac mortality. The adjusted relative risk was 13.3 for nsVT and 4.4 for SDNV>80 ms. Among patients with nsVT, mortality rate was significantly higher with SDNV>80 ms (58%), compared to lower SDNV (14%, p<0.01). Sixty-four percent mortality rate was observed in patients with LVEF<40%, presence of nsVT and SDNV>80 ms, compared to 17% in similar patients with lower SDNV (p<0.05). CONCLUSION: The analysis of coupling interval of ventricular premature beats form the same 24-h ECG recordings may complement the standard Holter analysis for risk stratification. This seems especially promising in the subgroups of patients at highest risk-those with LV systolic dysfunction, non-sustained VT or both.

[Prevalence of risk factors for atherosclerosis in participants of the Southern Poland Epidemiological Survey (SPES) with normal blood pressure]. / Wystepowanie czynników ryzyka miazdzycy wsród uczestników akcji profilaktyki pierwotnej Southern Poland Epidemiological Survey (SPES) z prawidlowym cisnieniem tetniczym.

Results of many studies indicate that cardiovascular diseases develop more often in subjects with blood pressure higher than optimal, but lower than the level, at which the diagnosis of arterial hypertension and implementation of therapy is justifiable. The aims of this study were the assessment of prevalence of risk factors for atherosclerosis among people with normal blood pressure in a population of Southern Poland (Southern Poland Epidemiological Survey--SPES), the quantitative evaluation of global risk for coronary events in relation to normal blood pressure classes, as well as the estimation of the size of subpopulation of subjects eligible for lipid-lowering treatment. A subpopulation of 15,484 subjects without known hypertension and coronary heart disease with normal blood pressure measurements were chosen from a total of 50,111 participants of the SPES study. There were 5,304 men and 10,180 women, aged from 18 to 87 years. Optimal blood pressure (< 120/80) was observed in 24%, normal (120-129/80-84) in 40% and high normal (130-139/85-89) in 35% subjects. In both sexes, irrespective of blood pressure classes, the most prevalent risk factors were hypercholesterolemia, overweight/obesity and smoking. The prevalence of hypercholesterolemia (> 200 mg/dl) increased along with blood pressure classes, and the proportion of subjects with cholesterol level > or = 240 was 1.5 times greater in those with high normal (21%), compared to those with optimal blood pressure (13%). The proportion of overweight/obesity was 1.5 times greater in subjects with high normal (50.5%) when compared to those with the optimal blood pressure (32.5%). The global risk for coronary events > 10% was more frequent in subjects with high normal blood pressure. Increase of the proportion of subjects eligible for lipid-lowering therapy from near 0% in women with optimal to approximately 10% in men and 8% in women with high normal blood pressure. A rise of the normal blood pressure class is associated with a clear increase in the prevalence of atherosclerotic risk factors and the global coronary risk. An extended medical care should be considered to all subjects with high normal blood pressure and global risk greater than 10%, including lipid-lowering therapy in approximately 10% of this subpopulation.

Age-adjustment of HRV measures and its prognostic value for risk assessment in patients late after myocardial infarction.

THE AIMS OF OUR STUDY WERE: (1) to establish the normal limit of the heart rate variability (HRV) indices in a healthy population and in its four age-related subgroups, including a new HRV index, HRV fraction; and (2) to analyse the frequency and predictive value of abnormally low HRV in a population of post-infarction patients in respect to the cut-points chosen (raw or age-adjusted). METHODS: Normal population of 296 healthy subjects (81 f, 215 m, aged 47+/-10 years) and post-infarction population of 298 patients (>3 months after acute MI, 65 f, 233 m, aged 56+/-10) were examined. The normal population was divided into 4 subsets based on age at entry: <35, 35-44, 45-54 and >54 years. Based on a 24 h ECG the standard HRV analysis was performed to obtain the following indices: mean RR interval, SDNN and SDANN. A new index of HRV, HRV fraction (HRVF, %) was calculated based on a numerical processing of the RR intervals return map. All patients were followed for 24 months. The endpoints of the study were death (of any reason) and cardiac death. RESULTS: Means and normal limits for SDNN, SDANN and HRVF were: 147+/-36 ms [95% CI 89-220], 136+/-36 ms [79-212] and 53+/-9% [35-68]. The HRV values below the lower normal limit (LNL) were observed in 20-25% of post-MI patients. During a 2 year follow-up there were 36 deaths (total mortality 12.1%), while cardiac mortality was 9.1% (27 cases). The prognostic value of the analysed indices was similar (sens approximately 53-61%, spec approximately 79-84%, PPV 22-26%, NPV 93-94%) irrespective of the cut-points chosen (calculated either for the entire population or age-related). Multivariate Cox regression analysis showed that a decrease of any index below the LNL was associated with a approximately 2.5 and approximately 4-6 times greater risk for death and cardiac death, irrespective of the cut-points chosen. CONCLUSIONS: The age-dependence of the HRV indices does not seem to significantly influence their prognostic value. Thus, a single cut-point of a particular HRV index, based on the entire population, is sufficient to be treated as a risk predictor. In the late phase of myocardial infarction the value of any global HRV index lying below the lower normal limit indicates independently an increased risk of death, especially cardiac death. The new index (HRV fraction) seems to be a promising substitute for currently used standard indices.