Obstructive sleep apnea severity is associated with left ventricular mass independent of other cardiovascular risk factors in morbid obesity.

OBJECTIVE: To evaluate the relation between obstructive sleep apnea (OSA) and left ventricular mass (LVM) in morbid obesity and the influence of gender, menopausal status, anthropometry, body composition, hypertension, and other cardiovascular risk factors in this relationship. DESIGN: Cross-sectional descriptive study. METHODS: Polysomnographic and echocardiographic studies were performed in a cohort of 242 patients (86 men, 100 premenopausal (PreM) and 56 postmenopausal (PostM) women), with grade II obesity and above (BMI: 43.7 ± 0.4 kg/m(2)) to investigate OSA and LVM respectively. Anthropometry, body composition, glucose tolerance, and blood pressure were also recorded. RESULTS: OSA to different degrees was diagnosed in 76.2% of the patients (n: 166), its prevalence being 90.9% (n: 70) for men, and 76% (n: 38) and 63.8% (n: 58) for PostM and PreM women, respectively (p < 0.01). LVM excess was greatest for PostM women (90.2%), followed by men (81.9%) and PreM females (69.6%) (p < 0.01). LVM values increased in accordance to OSA severity (absence, 193.7 ± 6.9 g; mild, 192.6 ± 7.8 g; moderate, 240.5 ± 12.5 g; severe, 273.6 ± 14.6 g; p < 0.01). LVM magnitude correlated with the menopausal state, age, central adiposity, hypertension (HT), type 2 diabetes (DM), desaturation index (DI), and apnea-hypopnea index (AHI) (r = 0.41; p < 0.01). The relationship between LVM and AHI persisted in the multivariate analysis (ß = 0.25; p < 0.05) after adjusting for age, gender, menopausal state, BMI, waist circumference, neck circumference, DI, fasting plasma glucose, DM, and HT. But if tobacco habits are included, the statistical difference disappears (ß = 0.22; p = 0.06). CONCLUSIONS: Morbid obesity is frequently associated with abnormal LVM, particularly in patients with OSA; this association is independent of HT, BMI, body composition, and other clinical factors, supporting a direct role of OSA on LVM in morbid obesity. This suggests that OSA and LVM might be taken as predictors of the cardiovascular risk in these patients.

Early and late troponin T determination after elective cardiac surgery. Two different meanings.

AIM: Although Troponins are demonstrated to be better predictors than CK-MB in quantification of myocardial damage, the relation between cut-off values for the diagnosis of perioperative myocardial infarction (PMI) and sample time is still not clear. In the present study we sought to analyse the clinical consequence of an early and late cTnt determinations after elective cardiac surgery. MATERIAL OF STUDY: Data of 117 patients undergone elective open heart surgery between January 2006 and June 2007 were prospectively collected. PMI was detected on the basis of postoperative electrocardiography/echocardiography and hemodynamic state. RESULTS: The in-hospital mortality was 1.7%. Eight patients (6.8%) presented PMI. Receiver-operating characteristic (ROC) analyses showed a cTnt cut-off of 1.22 mg/L (CI 0.94 to 0.99, P = 0.0001, 100% sensitivity and 96% specificity) on arrival to ICU for the diagnosis of PMI. On the second post-operative day the cut-off value was 2.8 mg/L (CI 95% 0.84 to 0.98, P = 0.0001) (sensitivity 66% and specificity 100%). At this time the Pearson's test revealed the best correlation to ICU (P = 0.008) and in-hospital (P = 0.01) length of stay (LOS). DISCUSSION: A better sensibility of cTnt in diagnosis of PMI in the early postoperative period has been demonstrated to be associated to an increasing specificity in the late post-operative period. CONCLUSIONS: PMI must be suspected in patients with a cTnt > 1.22 mg/L. A second later assessment on the 2nd post-operative can exclude false positives and significantly predict the ICU and the in-hospital length of stay.