effect of amlodipine and sildenafil on the NT-ProBNP level of patients with COPD-induced pulmonary hypertension

Pulmonary hypertension [PH] is an important cause of heart failure in chronic obstructive pulmonary disease [COPD]. The pro brain natriuretic peptide N-terminal [NT-proBNP] has been suggested as a noninvasive marker to evaluate ventricular function. However, there is no evidence to support the use of NT-proBNP in monitoring the benefits of vasodilators in COPD induced PH. Thus, we used NT-proBNP as a biomarker to evaluate the effect of oral vasodilators on cardiac function in COPD-induced PH. Forty clinically-stable PH patients were enrolled with history of COPD, normal left ventricular ejection-fraction [LVEF], right ventricular systolic pressure [RVSP] > 45 mmHg and baseline blood NT-proBNP levels >100 pg/mL. Patients were randomized into two groups, one group received sildenafil and second group were given amlodipine for two weeks. NT- proBNP and systolic pulmonary arterial pressure [systolic PA-pressure] were measured at the beginning and the end of study. Mean NT-proBNP level in the first group was 1297 +/- 912 pg/mL before therapy and 554 +/- 5 pg/mL after two weeks drug therapy, respectively. Similarly, in second group NT- proBNP level was 1657 +/- 989 pg/mL and 646 +/- 5 pg/mL before and after treatment. Amlodipine or sildenafil significantly reduced NT-proBNP levels in COPD-induced PH patients [p < 0.05]. Our study shows that amlodipine and sildenafil have a similar effect on NT-proBNP levels. In both groups NT- proBNP levels were significantly reduced after treatment. Therefore, our findings support the potential benefits of treatment with vasodilators in COPD induced PH

Evaluation of maximum o[2] consumption: using ergo-spirometry in severe heart failure

Although sport-physiologists have repeatedly analyzed respiratory gases through exercise, it is relatively new in the cardiovascular field and is obviously more acceptable than standard exercise test, which gives only information about the existence or absence of cardiovascular diseases [CVDs]. Through the new method of exercise test, parameters including aerobic and anaerobic are checked and monitored. 22 severe cases of heart failure, who were candidates of heart transplantation, referring to Massih Daneshvari Hospital in Tehran from Nov. 2007 to Nov. 2008 enrolled this study. The study was designed as a cross-sectional performance and evaluated only patients with ejection fraction less than 30%. O[2] mean consumption was 6.27 +/- 4.9 ml/kg/min at rest and 9.48 +/- 3.38 at anaerobic threshold [AT] exceeding 13 ml/kg/min in maximum which was significantly more than the expected levels. Respiratory exchange ratio [RER] was over 1 for all patients. This study could not find any statistical correlations between VO2 max and participants' ergonomic factors such as age, height, weight, BMI, as well as EF. This study showed no significant correlation between VO[2 max] and maximum heart rate [HR [max]], although O[2] maximum consumption was rationally correlated with expiratory ventilation. This means that the patients achieved maximum ventilation through exercise in this study, but failed to have their maximum heart rate being led probably by HF-induced brady-arrhythmia or deconditioning of skeletal muscles

Ventilator-associated pneumonia: evaluation of etiology, microbiology and resistance patterns in a tertiary respiratory center

Ventilator-associated pneumonia [VAP] has been reported as the most common hospital-acquired infection among patients requiring mechanical ventilation. This study aimed to determine the incidence of ventilator-associated pneumonia in a cardiopulmonary tertiary center, and to evaluate its etiology, resistance patterns, and outcome of admitted patients. In a retrospective study, patients admitted to the Masih Daneshvari Hospital, a tertiary cardiopulmonary center, were evaluated in a 7-month period. A total of 530 patients were admitted to the ICU out of which, 40 acquired VAP. Overall, 99 patients were evaluated [male 57, female= 42] including 40 VAP and 59 non- VAP cases. The incidence of VAP was estimated to be 7.5% in this unit. The underlying conditions included respiratory diseases [COPD, asthma, etc], and cardiac problems [post "coronary artery bypass graft" CABG, etc]. Also, patients in the thoracic surgery ward and those with renal, gastrointestinal, neurologic and other medical problems were evaluated. The patients were divided into two groups of VAP and non-VAP cases. The micro-organisms were recovered from the patients' bronchoalveolar lavage fluid. The most common micro-organisms recovered were Pseudomonas aeruginosa [17 cases] and Staph. aureus species [15 cases]. In VAP patients in whom S. aureus was recovered, 80 percent of species were methicillin-resistant [MRSA] but all were sensitive to Vancomycin. Moreover, resistance to two, three or four antibiotics was seen in 12, 10, and 5 patients, respectively, in whom P. aeruginosa was recovered. The prevalence of S. aureus in patients with respiratory problems was more than other groups [including MRSA species], but the prevalence of recovered P. aeruginosa was the lowest in respiratory patients, compared to other groups. Also the mortality rate in drug resistant S. aureus and P. aeruginosa groups were 42 and 47 percent, respectively. Length of stay for MRSA group was 80% and death rate was 50%. In P. aeruginosa group, there was a positive relationship between resistance to multiple drugs and mortality and also ICU stay. VAP is a common infection in ICU setting and certain interventions may affect its incidence. In our study, P. aeruginosa and S. aureus were more common in ICU patients. Pseudomonas species were associated with the highest mortality rate and were resistant to four antibiotics in the antibiogram testing. S. aureus species were more common in patients with underlying respiratory problems, compared to those with other conditions

Predictive accuracy of revised Geneva score in the diagnosis of pulmonary embolism

Revised Geneva score is a clinical prediction rule used in determining the pre-test probability of pulmonary embolism [PE]. It has been recently introduced and is independent of the doctor's experience applying the rule. This study aimed to evaluate the predictive accuracy of revised Geneva score in the diagnostic protocol of pulmonary embolism and its role in decreasing the need for pulmonary imaging studies. In this study, we evaluated the medical records of 242 patients suspected for pulmonary embolism who underwent CT scan of the lung as part of their diagnostic protocol from October 2007 to February 2009. Six patients were excluded from the study due to their indeterminate CT scan results. The mean age of patients was 58 yrs and 62% of patients were males. The overall prevalence of pulmonary embolism was 24%. By increased scoring, the clinical probability of pulmonary embolism increased as well [P=0.011]. According to the classification of revised Geneva score, clinical probability of pulmonary embolism was evaluated to be low in 25% of patients, intermediate in 72% and high in 2%. Prevalence of pulmonary embolism based on the CT scan results was 7.7% ranged [0.5-14.9] in the low probability category, 22.5% ranged [15.6-29.4] in the intermediate, and 50% ranged [0.01-0.99] in the high-probability category which were comparable with the rates reported in the derivation set except for the prevalence rate for high probability patients [9%, 27.5% and 71.7%, respectively]. The area under the ROC curve was calculated based on continuous scoring to be 0.675. Revised Geneva score had an acceptable predictive accuracy in low and intermediate-probability groups. We could not reach a conclusion regarding high probability patients due to the small number of such cases in this study

Respiratory disturbance index and severity of airway obstruction in COPD patients

Chronic obstructive pulmonary disease [COPD] is a common disease and concomitant occurrence with obstructive sleep apnea [OSA] has been reported in some studies. This coincidence can result in exacerbation of common complications like exacerbated hypoxemia, hyperpnea and right-sided heart failure. Thus, we decided to evaluate and compare respiratory disturbance index [RDI] and sleep apnea in COPD patients. For this purpose, 50 COPD patients with OSA were studied between 2003 and 2004. OSA criteria included obstructive apnea and clinical symptoms of snoring, sleep disorder and RDI >/= 5. The patients were divided in to two groups: group 1 consisted of 11 patients [22%] with FEV1/FVC<70 with the mean age of 36.18 +/- 14 and group 2 was included 39 patients [78%] with FEV1/FVC >/= 70 with the mean of 84.75 +/- 6.6%. RDI was compared between the two groups using independent sample t-test. Multiple regression analysis was also used for comparing other variables like height, weight, age, etc. The understudy patients were included 19 females [38%] and 31 males [62%] with the mean age of 53.7 +/- 14.8 yrs. There were statistically significant differences in RDI and height between the two groups [p=0.028 and p=0.00, respectively]. However, no significant difference was detected between the two groups in terms of weight and body mass index [BMI]. The possibility of concomitant occurrence of COPD and OSA should be considered due to co-occurrence of significant respiratory symptoms [like dyspnea, sleepiness, etc.] and assessed by adding RDI to important indices like height and so on