Clinical value of cardiopulmonary exercise testing derived oxygen uptake efficiency parameters in patients with end-stage chronic heart failure / 中华心血管病杂志

<p><b>OBJECTIVE</b>To assess the cardiopulmonary exercise testing (CPET) derived performance of oxygen uptake and ventilation efficiency parameters, including oxygen uptake efficiency plateau (OUEP) , oxygen uptake efficiency slope (OUES), V·E/V·CO2 slope and lowest V·E/V·CO2, in patients with end-stage chronic heart failure (CHF) and evaluate their clinical value on monitoring cardiac function and hemodynamic status.</p><p><b>METHODS</b>A total of 26 end-stage CHF patients considered for heart transplantation were enrolled in this study. CPET, echocardiography and invasive hemodynamic examinations with Swan-Ganz flowing balloon catheter were performed. Correlation analysis was made between oxygen uptake and ventilation efficiency parameters from CPET and echocardiographic and hemodynamic parameters.</p><p><b>RESULTS</b>OUEP and OUES showed good correlation with peak oxygen consumption (peak V·O2) (r = 0.535, P < 0.01;r = 0.840, P < 0.001). In end-stage CHF patients, the slope of OUEP with respect to peak V·O2 is about 32, but the slope of OUES with respect to peak V·O2 is only about 2. The difference was 16 times. The change of OUEP was more sensitive and significant than those of OUES and peak V·O2 (P < 0.05). OUEP, peak V·O2 (%pred), V·E/V·CO2 slope and lowest V·E/V·CO2 were all correlated well with non-invasive hemodynamic parameters peak cardiac output (r = 0.535, P < 0.01; r = 0.652, P < 0.001; r = -0.640, P < 0.001; r = -0.606, P = 0.001 respectively) and peak cardiac index (r = 0.556, P < 0.01;r = 0.772, P < 0.001; r = -0.641, P < 0.001; r = -0.620, P < 0.001 respectively) derived from CPET, but not correlated with invasive hemodynamic parameters cardiac output and cardiac index at rest (P > 0.05). Both peak V·O2 (%pred) and V·E/V·CO2 slope were significantly correlated with invasive hemodynamic parameters systolic pulmonary arterial pressure (r = -0.424, P < 0.05; r = 0.509, P < 0.01) and mean pulmonary arterial pressure (r = -0.479, P < 0.05; r = 0.405, P < 0.05). Peak V·O2 (%pred) was also significantly correlated with pulmonary capillary wedge pressure (r = -0.415, P < 0.05), and V·E/V·CO2 slope was significantly correlated with pulmonary vascular resistance (r = 0.429, P < 0.05).</p><p><b>CONCLUSIONS</b>The oxygen uptake and ventilation efficiency parameters derived from CPET, including peak V·O2, OUEP, lowest V·E/V·CO2 and V·E/V·CO2 slope etc, are objectively monitoring and evaluating cardiac function and hemodynamic status. And they are useful for optimizing clinical management of patients with end-stage CHF.</p>

Prevalence of hypertension and associated factors among older rural adults: results from liaoning province, China

The objective of the study was to estimate the prevalence of hypertension and associated factors among older rural adults in Liaoning Province, China. The study was conducted in 2004-2006, using a multistage, stratified clustering sampling scheme to select a representative sample. A total of 10,065 adults aged 60 years or older were examined. A survey of blood pressure and associated factors was carried out. All data analyses were conducted using SPSS 11.5 statistical software package. Overall, the prevalence rates of hypertension are 57, 64.4 and 64.9% for the age groups 60-69, 70-79 and >/= 80 years, respectively. The prevalence of hypertension was positively correlated with age, female gender, Mongolian ethnicity, overweight and obesity, smoking and drinking, whereas income level was a protective factor for hypertension. The rates of awareness, treatment and control among older rural adults were very low [overall 35.2, 28.7 and 1.0%, respectively] Hypertension was highly prevalent among older rural adults in Liaoning Province, and it was associated with many factors. The percentages of hypertensives who were aware, treated, and controlled were very low. These data underscore the urgent need to strengthen the public health education and blood pressure monitoring system to better manager hypertension among older adults in rural China