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This study was designed to determine the value of automatic corrected QT-interval measurement in Holter tapes in patients after myocardial infarction as a marker of life-threatening ventricular arrhythmias. We compared the corrected QT interval, automatically measured in 24-hour Holter recordings, in two groups of patients after myocardial infarction: group I was composed of 14 patients admitted consecutively to our hospital for documented sustained ventricular tachycardia or out-of-hospital cardiac arrest. Group II consisted of 28 patients with previous myocardial infarction with characteristics similar to those of group I, but without malignant ventricular arrhythmias in the follow-up. The global mean 24-hour corrected QT interval was longer in group I (425 +/- 20 msec) than in those patients after myocardial infarction without arrhythmias (group II) (405 +/- 17 msec; p0.01). Furthermore, a significant proportion of patients of group I (seven of 14) exhibited more peaks of corrected QT longer than 500 msec compared with patients of group II (two of 28; p0.005). A circadian rhythm of corrected QT peaks was observed in group I, having a significantly higher incidence from 11 PM to 11 AM (p0.05). We conclude that automatic corrected QT-interval measurement on Holter electrocardiogram is now available and feasible. Our results suggest that this is a marker for risk assessment of life-threatening ventricular arrhythmias. Large-scale trials are needed to confirm these results and to determine the predictive value of this technique for risk stratification.

Background Chest pain is a frequent symptom in the emergency department and often presents a diagnostic challenge. Because coronary thrombosis is a hallmark of acute ischemic syndromes, the substrates of the coagulation and fibrinolysis cascades may be markers of coronary ischemia. The objective of this study was to determine the diagnostic value of several hemostatic markers in patients presenting to the emergency department (ED) with chest pain syndromes. Methods Two hundred fifty-seven consecutive patients with acute chest pain were studied in this prospective study conducted in an urban ED. D- Dimer levels were measured at admission to the ED in all patients. We also measured thrombin-antithrombin complexes, prothrombin fragment 1+2, activated factor VII, and fibrinogen. We used regression analysis to estimate the likelihood of myocardial infarction and the diagnostic value of D -dimer. Results D -Dimer and fibrinogen levels were significantly higher in patients with acute ischemic events (myocardial infarction and unstable angina) than in nonischemic patients ( P P =.02, respectively). The other hemostatic markers were not significantly elevated in patients with ischemic events. D -Dimer level >500 μg/L had an independent diagnostic value for myocardial infarction and increased the diagnostic sensitivity of the electrocardiogram and history from 73% to 92%. Conclusion D -Dimer, an expression of ongoing thrombus formation and lysis, is a marker of substantial incremental value for the early diagnosis of acute coronary syndromes presenting with chest pain. It adds independent information to the traditional assessment for myocardial infarction. D -Dimer can be incorporated into clinical decision models in the ED. (Am Heart J 2000;140:379-84.)

Thrombosis of the superior vena cava and other central venous trunks is a complication that is associated with the implantation of pacemakers and central venous catheters that are used for chemotherapy or total parenteral nutrition. This complication occurs somewhat more frequently than expected because many of these thrombi are clinically unnoticed and are finally diagnosed at autopsy. Phlebographic studies have shown that thrombosis is related to central venous catheters in up to 52 “;# of patients who have not received anticoagulation therapy.l This complication may be treated satisfactorily with fibrinolytic agents such as streptokinase (SK), urokinase (UK), and tissue plasminogen activator. We report a patient with ischemic heart disease who had a catheter-related superior vena cava thrombosis with protrusion of the thrombus t,owards the right atrium, successfully treated with SK. Diagnosis and follow-up examinations were carried out by transthoracic and biplane transesophageal echocardiography. The patient was a 59-year-old man who had antecedents