Commonly used reference values underestimate oxygen uptake in healthy, 50-year-old Swedish women.

Cardiopulmonary exercise testing (CPET) is the gold standard among clinical exercise tests. It combines a conventional stress test with measurement of oxygen uptake (VO2 ) and CO2 production. No validated Swedish reference values exist, and reference values in women are generally understudied. Moreover, the importance of achieved respiratory exchange ratio (RER) and the significance of breathing reserve (BR) at peak exercise in healthy individuals are poorly understood. We compared VO2 at maximal load (peakVO2 ) and anaerobic threshold (VO2@AT ) in healthy Swedish individuals with commonly used reference values, taking gender into account. Further, we analysed maximal workload and peakVO2 with regard to peak RER and BR. In all, 181 healthy, 50-year-old individuals (91 women) performed CPET. PeakVO2 was best predicted using Jones et al. (100·5%), while SHIP reference values underestimated peakVO2 most: 112·5%. Furthermore, underestimation of peakVO2 in women was found for all studied reference values (P<0·001) and was largest for SHIP: women had 128% of predicted peakVO2 , while men had 104%. PeakVO2 was similar in subjects with peak RER of 1-1·1 and RER > 1·1 (2 328·7 versus 2 176·7 ml min-1 , P = 0·11). Lower BR (≤30%) related to significantly higher peakVO2 (P<0·001). In conclusion, peakVO2 was best predicted by Jones. All studied reference values underestimated oxygen uptake in women. No evidence for demanding RER > 1·1 in healthy individuals was found. A lowered BR is probably a normal response to higher workloads in healthy individuals.

Cardiac function after hematopoietic cell transplantation: an echocardiographic cross-sectional study in young adults treated in childhood.

BACKGROUND: Hematopoietic cell transplantation (HCT) including preparative regimens with chemotherapy and total body irradiation (TBI) is an accepted treatment for many malignant disorders but may have side-effects for several organs, including the cardiovascular system. The aim of this study was to study very long-term consequences on cardiac function after childhood HCT. PROCEDURE: Cardiac function was evaluated using echocardiography and levels of NT-proBNP and growth hormone (GHmax) in 18 patients, at a median of 18 years after HCT including TBI, and in 18 matched controls. RESULTS: Patients after HCT had cardiac dimensions, volumes, and left ventricular ejection fractions within normal range after correction for body size. However, compared with the control group, patients after HCT had significantly lower E/A ratio, as a measure of left ventricular diastolic function, significantly lower fractional shortening and mitral annular plane systolic excursion, as measures of left ventricular systolic function, significantly lower tricuspid annular plane systolic excursion, as a measure of right ventricular function, and significantly higher NT-proBNP, as a measure of total cardiac function. Also, pulmonary flow acceleration time was shorter in the group after HCT, indicating possible pulmonary involvement. Heart rate was significantly higher and GHmax significantly lower in patients after HCT. CONCLUSIONS: Almost two decades after HCT, including preparative regimens with TBI, cardiac function in patients was found to be within normal range. However, when compared with a healthy control group, patients after HCT showed lower systolic and diastolic left ventricular function as well as lower right ventricular function.

ST depression in ECG at entry indicates severe coronary lesions and large benefits of an early invasive treatment strategy in unstable coronary artery disease; the FRISC II ECG substudy. The Fast Revascularisation during InStability in Coronary artery disease.

BACKGROUND: In unstable coronary artery disease, ST-segment depression indicates a poor prognosis. We evaluated whether the effect of early revascularization and the extent of coronary lesions were related to ST-segment and T wave changes on admission. METHODS AND RESULTS: 2457 patients with unstable coronary artery disease were randomized to an early invasive strategy with coronary angiography/revascularization within 7 days or to a non-invasive strategy with coronary procedures only when symptoms or severe ischaemia recurred. ST depression was present in 1114 (45.5%) patients. In the invasive group, 45% of the patients with ST depression had three-vessel disease or left main stenosis compared with 22% if no ST-segment depression was present, PP=0.004 while mortality was changed from 5.8 to 3.3%, P=0.050. In patients without ST-segment depression the corresponding rates concerning death/myocardial infarction were 10.4 and 8.9, and for mortality 2.0 and 1.2% (non-significant). CONCLUSIONS: In unstable coronary artery disease, ST-segment depression is associated with a 100% increase in the occurrence of three-vessel/left main disease and to an increased risk of subsequent cardiac events. In these patients an early invasive strategy substantially decreases death/myocardial infarction.

Origin and relationship between different cell types in malignant fibrous histiocytoma.

The derivation of histiocyte-like cells in malignant fibrous histiocytoma (MFH) has been a matter of debate. To shed light on this problem two cell lines from two subsequent recurrencies of MFH were established. The existence of two different cell populations, mainly fibroblast-like in the first cell line and mainly histiocyte-like in the second, was shown by light and electron microscopy, DNA measurements, and karyotype analysis. By detailed banding analysis and identification of several identical chromosomal marker types in the two cell lines, it was proven that they originally derived from the same single cell or single clone. Because the first cell line, with mainly fibroblast-like cells, was in the hypotriploid region and the second, with mainly histiocyte-like cells, was in the penta-hexaploid region, the data explained the appearance of histiocyte-like cells in MFH as a consequence of chromosomal progression.