Comparison of degrees of left ventricular dilation within three hours and up to six days after onset of first acute myocardial infarction.

Following an acute myocardial infarction (AMI) there is immediate deterioration of contractility in the infarcted left ventricular (LV) wall. This can be followed by regional dilation (expansion) as well as global remodeling. We examined 35 consecutive patients--with no history of myocardial ischemia--who were admitted to hospital within 3 hours after initial symptoms and with ST-segment changes on an electrocardiogram consistent with transmural ischemia. Echocardiography was performed at admission, and at 6 hours, 12 hours, 24 hours, 3 days, and 6 days after onset of the AMI. Within 3 hours after onset of symptoms an increase in both end-diastolic volume index (EDVI) and end-systolic volume index (ESVI) was found in both anterior and inferior infarcts when compared with healthy controls (mean +/- SD EDVI: 99 +/- 13 ml/m2 [anterior], 69 +/- 17 ml/m2 [inferior], 51 +/- 15 ml/m2 [controls], p < or = 0.00001; ESVI: 62 +/- 12 ml/m2 [anterior], 38 +/- 11 ml/m2 [inferior], 17 +/- 6 ml/m2 [controls], p < or = 0.00001). At all points in time, volumes were larger in anterior infarcts than in inferior infarcts (p < 0.05). The volumes did not change during the 6 days (p > 0.1). Thus, major LV dilation is present within 3 hours after onset of symptoms of first AMI. The dilation is more pronounced in anterior versus inferior infarcts. From 3 hours until day 6 no further changes in LV volumes occurred.

The prognostic value of exercise testing early after myocardial infarction in patients treated with thrombolytics.

Exercise testing early post AMI was evaluated as a predictor of reinfarction in patients treated with thrombolytics. AMI patients exercise-tested prior to discharge were included in the study (n = 178). The patients were followed for 2.9 +/- 0.9 years (mean +/- 1 SD) for the development of new cardiac events defined as cardiac death or reinfarction. Cox regression analysis of clinical and exercise test variables showed that there was significant predictive value of treating heart failure with drugs from two or more therapeutic groups (P < 0.001; hazard ratio 9.4 (3.1-28.2) (estimate and 95% confidence interval)), such as those with a previous history of myocardial infarction (P = 0.001; hazard ratio 4.0 (1.7-9.6)) and of significant ST depression (P = 0.029; hazard ratio 2.5 (1.1-5.7)). Significant ST depression could be substituted by the delta ST/delta HR index (P = 0.042; hazard ratio 2.8 (1.2-6.8)). The exercise test had independent but limited prognostic value in AMI patients treated with thrombolytics. The delta ST/delta HR index did not improve the predictive value of the exercise test.

[Is Vibrio cholerae serotype 0139 a potential cause of a new pandemic?]. / Vibrio cholerae serotype O139 årsag til ny pandemi?

Vibrio cholerae O139, a new V. cholerae serotype that does not react with the 138 so far known antisera, was first isolated in 1992 in Madras, India. Although a V. cholerae non-O1, it behaved quite differently from this particular group of organisms by its clinical appearance in causing epidemic cholera-like disease. The organism possessed the same register of virulence factors as V. cholerae O1. Biochemical and genetic analyses have shown that V. cholerae O139 was closely related to the El Tor biotype and it has been suggested that it might be a mutant of this biotype. Despite the fact that V. cholerae O139 isolates were very homologous in many respects, ribotyping of Thai isolates showed a certain degree of genetic diversity. From its rapid spread in populations, pattern of infection and ability to survive in aquatic environments, it may be suggested that we are dealing with a more infectious, more virulent and in an ecological sense more robust organism, whose pandemic potential appears significant. Commercial cholera vaccines offer no or only limited protection. Treatment comprises an adequate rehydration and use of effective antibiotics--at present tetracycline, ampicillin, erythromycin and ciprofloxacin. Tourism and perhaps the import of foods from Third World countries may excert a potential risk for the Danish population.