Oxidative stress markers predict early left ventricular systolic dysfunction after acute myocardial infarction treated with primary percutaneous coronary intervention.

BACKGROUND: Despite successful primary percutaneous coronary intervention (PCI) after ST-segment elevation myocardial infarction (STEMI), some patients develop left ventricular systolic dysfunction (LVSD) and acute heart failure (HF). Identifying patients with an increased risk of developing LVSD by means of biomarkers may help select patients requiring more aggressive therapy. OBJECTIVES: The aim of this study was to evaluate the relationship between the levels of oxidative stress markers and development of LVSD and acute HF early after STEMI. MATERIAL AND METHODS: The study enrolled 148 patients with the first STEMI, who were treated by primary PCI < 12 h from the onset of symptoms. We assessed the impact of different biomarkers for developing LVSD and acute HF (Killip ≥ 2) including: markers of necrosis - peak creatine kinase (CK), markers of myocardial stretch - B-type natriuretic peptide (BNP), inflammatory markers - C-reactive protein (CRP), leucocyte and neutrophil count, as well as oxidative stress markers - total thiol groups, catalase, superoxide dismutase (SOD) and glutathione reductase (GR). RESULTS: In multivariate analysis, thiol groups, peak CK, anterior wall infarction, and age were predictors of LVEF ≤ 40%. Out of 16 variables significantly associated with the Killip ≥ 2 in univariate logistic regression analysis, 5 appeared to be independently associated with acute HF in multivariate analysis: catalase, BNP, leucocytes, neutrophil count, and size of left atrium. CONCLUSIONS: In this study, we have shown for the first time that thiol groups and catalase are independent predictors of STEMI complication - LVSD and acute HF, respectively. Beside routine used biomarkers of necrosis and myocardial stretch, thiol groups and catalase may provide additional information regarding the risk stratification.

The long-term risk of stroke in patients with acute myocardial infarction complicated with new-onset atrial fibrillation.

BACKGROUND: The long-term risk of stroke after acute myocardial infarction (AMI) complicated with new-onset atrial fibrillation (AF) remains unclear. The aim of this study was to determine the long-term risk of AF and stroke in patients with AMI complicated with new-onset AF. METHODS: Patients with AMI complicated with new-onset AF (n = 260) and those without new-onset AF (n = 292) were followed for a mean of 7 years. All patients had sinus rhythm at hospital discharge. RESULTS: During the follow-up, AMI patients with new-onset AF had more frequent AF than those without new-onset AF (10.4% vs 2.7%, respectively; P < 0.0001). New-onset AF during AMI was a significant predictor of subsequent AF occurrence (the time elapsing between 2 consecutive R waves [RR] = 3.15, P = 0.004); but AF recurrence in follow-up (RR = 5.08, P = 0.001) and non-anticoagulation at discharge (RR = 0.29, P = 0.008) were independent predictors of stroke (Cox regression analysis). A period of 3.5 hours of AF within the first 48 hours of AMI was the high sensitivity cut-off level for the prediction of low long-term risk of stroke obtained by receiver operating characteristic analysis. Among patients who did not receive anticoagulants at discharge, the patients with short AF did not experience stroke and AF recurrence during follow-up, while those in the other group developed it (10.8%, P = 0.038 and 13.5%, P = 0.019, respectively). CONCLUSION: New-onset AF during AMI identifies the patients at long-term risk for stroke who may potentially benefit from anticoagulant therapy. Atrial fibrillation recurrence in follow-up was independently related to the development of stroke. However, for low-risk patients with AF (those with short AF occurring early in AMI) long-term anticoagulants might not be required.

Randomized active-controlled study comparing effects of treatment with carvedilol versus metoprolol in patients with left ventricular dysfunction after acute myocardial infarction.

BACKGROUND: Carvedilol has previously been demonstrated to be beneficial in patients with acute myocardial infarction (AMI) and left ventricular (LV) dysfunction. However, metoprolol has not to date been randomly evaluated in the same patient population. The objective of this study was to compare the effects of treatment with carvedilol versus metoprolol in patients with LV dysfunction after AMI. METHODS: The study enrolled 313 high-risk patients with anterior AMI and LV ejection fraction of <45%, randomly assigned to treatment with carvedilol or metoprolol. Patients were followed-up for a mean period of 13.4 months. The primary end point was time to composite adverse events (t-CAE). The secondary end points were time to composite hard events (t-CHE) and health-related quality of life. RESULTS: No differences were found either in the primary end point of t-CAE or in the secondary end point of t-CHE. A significant benefit was observed in 4 of 8 health-related quality of life domains in the carvedilol group, with fewer carvedilol group patients being withdrawn from therapy in the hospital. CONCLUSIONS: Treatment with carvedilol, in comparison to that with metoprolol in patients with AMI and LV dysfunction, did not differ significantly in regard to the primary end point of t-CAE or to the secondary end point of t-CHE but resulted in better long-term quality of life and favorable early safety profile.

Outcome of patients in relation to duration of new-onset atrial fibrillation following acute myocardial infarction.

AIM: The duration of new-onset atrial fibrillation (AF) following the acute myocardial infarction (AMI) was evaluated as well as its relation to in-hospital and 7-year mortality. METHODS AND RESULTS: A total of 320 consecutive patients with AF following AMI were examined and patients with AF <7 h (n = 141) were compared to those with AF > or =7 h in duration (n = 179). Receiver Operating Characteristic analysis was performed to identify the most useful AF duration cut-off level for the prediction of poor outcome. Patients with longer AF duration were older and had more advanced heart failure than patients with short arrhythmia duration. Patients with longer AF duration had worse outcome, including higher in-hospital (22.3 vs. 12.8%) and 7-year (67.4 vs. 34.4%) mortality. After multivariate adjustment, longer AF duration remained an independent predictor of long-term mortality (relative risk = 2.04, 95% confidence interval = 1.39-2.99, p = 0.0002). CONCLUSION: New-onset AF > or =7 h in duration following the AMI independently predicts long-term mortality.

Adenosine cardioprotection study in clinical setting of paroxysmal supraventricular tachycardia.

PSVT attack of >20min and frequency >160 is well-recognized model of myocardial dysfunction. We measured 6-keto-PGF1alpha and TXB(2) before and after adenosine administration to assess its cardioprotective potential. A total of 64 patients were randomly assigned as having acute episode of PSVT to adenosine or verapamil group. A bolus of 6mg of adenosine up to the maximum dose of 12 or 5mg of verapamil up to the maximum dose of 10mg were given, until the sinus rhythm was restored. The levels of PGI(2), TXA(2) and TAS were measured in three different time intervals. In adenosine group all parameters were normalized after 20min of conversion to sinus rhythm. The ratio of PGI(2)/TXA(2) increased after 5min of conversion to SR (P<0.01). Also, the ratio of TXA(2)/TAS was decreased for ADO (P<0.01). This is the first study to demonstrate that adenosine exerts cardioprotective effect.

Significance of recurrences of new atrial fibrillation in acute myocardial infarction.

BACKGROUND: Although new-onset atrial fibrillation (AF) frequently recurs following the acute myocardial infarction, the significance of AF recurrences is unknown. OBJECTIVE: The objective of the present study was to evaluate the incidence, clinical predictors and prognostic significance of AF recurrences following the acute myocardial infarction. METHODS AND RESULTS: A total of 320 consecutive patients with AF following the acute myocardial infarction were evaluated and the patients with AF recurrences were compared to those with single episodes of AF in whom AF did not recur after restoration of sinus rhythm. The incidence of AF recurrences was 22.5%. AF recurrences were highly associated with congestive heart failure and worse Killip class was identified as the most important predictor of AF recurrences. Patients with AF recurrences had poorer outcome, including higher in-hospital (36.1% versus 12.9%) and 7-year (68.2% versus 48.6%) mortality. After multivariate adjustment, AF recurrence remained an independent predictor of in-hospital [odds ratio (OR) = 3.08, 95% confidence interval (CI), 1.45-6.53, p = 0.001], and 7-year [relative risk (RR) = 1.52, 95% CI, 1.00-2.31, p = 0.026] mortality. CONCLUSION: New-onset AF frequently recurs following the acute myocardial infarction and our analysis demonstrated that recurrences of AF independently predicted in-hospital and long-term mortality.

Prognostic significance of new atrial fibrillation and its relation to heart failure following acute myocardial infarction.

BACKGROUND: New-onset atrial fibrillation (AF) after acute myocardial infarction (AMI) frequently occurs in association with postinfarction complications, particularly with heart failure (HF). AIMS: To evaluate whether postinfarction HF is associated with the subsequent development of AF and whether AF independently predicts poorer prognosis. METHODS AND RESULTS: We examined 650 patients with AMI and compared patients with AF (n=320) to those without (n=330). AF patients were classified as either early AF (n=208)-patients who developed AF within 24 h of symptom onset or late AF (n=112)-patients who had AF thereafter. We compared outcomes between these groups, adjusting for differences in baseline characteristics and postinfarction HF. Heart failure was the most important predictor of AF. In most patients, AF occurred secondary to HF. AF patients had poorer outcomes, including higher in-hospital and 7-year mortality. After multivariate adjustment, overall, AF was not an independent predictor of in-hospital [odds ratio (OR)=0.70) and 7-year [relative risk (RR)=1.14] mortality, but late AF remained an independent predictor of 7-year (RR=2.48, 95% confidence interval, 1.26-4.87) mortality. CONCLUSIONS: Heart failure mostly preceded the occurrence of new-onset atrial fibrillation after acute myocardial infarction, but only late atrial fibrillation was independently related to long-term mortality.