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.

Myocardial contrast echocardiography is a valuable technique for demonstration and delineation of regions of myocardial underperfusion secondary to coronary occlusion and/or significant coronary stenosis. Various contrast materials have been used. The aim of this study was to determine whether myocardial contrast echocardiography by the original contrast agent AQ-DDT (albumin based), produced in the Institute for Cardiovascular Diseases, Clinical Center of Serbia in Belgrade can be used in the detection and quantification of regions of myocardial perfusion defects. In 14 adult open chest dogs the perfusion defect was produced by selective coronary ligations (30 seconds) and was observed with epicardial contrast two-dimensional echocardiography. For administration of contrast a modified pigtail catheter was positioned in the aorta just above the aortic valves. In this way the perfusion regions of the left main and right coronary artery were included. The left anterior descending and left circumflex artery could not be selectively injected with contrast agent and their individual perfusion areas were not clearly demonstrated. In all cases contrast echocardiography images of the left ventricle were obtained in a short-axis cross-sectional view at the mid-papillary muscle level. Forty-two injections of AQ-DDT for perfusion analysis were done, and were recorded on a VHS recorder. Quantification of the quality in demonstrating myocardial perfusion was scored as good, poor or without visual echocardiographic effect, by an investigator experienced in echocardiography, immediately and one month later. There was 100% agreement in the scoring. Our results indicated that agent AQ-DDT produces a good contrast effect (echocardiography visualization) in dogs and has the potential to demonstrate regional perfusion defects of the myocardium. Its potential role in human medicine, for diagnosis and evaluation of the results of interventional therapy, especially during aortocoronary bypass graft surgery, should be evaluated

No abstract