Effects of CPAP on right ventricular myocardial performance index in obstructive sleep apnea patients without hypertension

OBJECTIVES: Obstructive sleep apnoea (OSA) might cause right ventricular dysfunction and pulmonary hypertension. We aimed to determine the effects of nasal continuous positive airway pressure (CPAP) therapy on right ventricular myocardial performance index (MPI) in OSA patients without hypertension. METHODS: 49 subjects without hypertension, diabetes mellitus, any cardiac and pulmonary disease had overnight polysomnography and echocardiography. In 18 moderate-severe OSA (apnea-hypopnea index ≥ 15) patients, right ventricular free wall diameter (RVFWD) was measured by M-mode, and right ventricular MPI was calculated as (isovolumic contraction time+ isovolumic relaxation time) / pulmonary ejection time using Doppler at baseline and after 6 months CPAP therapy. RESULTS: Mean age was 46.5 ± 4.9 year. Patients had high body mass index (BMI: 30.6 ± 4,0 kg/m(2)), but there was no change in either BMI or blood pressures after 6 months. Right ventricular end-diastolic and end-systolic diameters were in normal limits at baseline, and did not change after CPAP usage. Baseline RVFWD (7.1 ± 2.1 mm) significantly decreased after CPAP therapy (6.2 ± 1.7 mm, p < 0.001). 15 of patients (83%) had right ventricular diastolic dysfunction at baseline, and it was completely improved in 11 of them (73%) by CPAP usage. Right ventricular global dysfunction was shown in 11 patients (61%) with a high MPI (62.2 ± 9.3%) at baseline; and MPI was significantly decreased after CPAP therapy (47.3 ± 8.4%, p < 0.0001), and it was completely corrected in 4 of them (36%). CONCLUSION: CPAP therapy significantly decreases RVFWD and improves right ventricular diastolic and global functions (MPI) in OSA patients without hypertension

The effects of Juglone-Selenium combination on invasion and metastasis in pancreatic cancer cell lines

Background: Pancreatic cancer does not show any symptoms in the early period and metastatic process is already passed when the diagnosis is done. Therefore, in the battle with pancreatic cancer, novel treatment strategies, particularly antiinvasive and antimetastatic strategies, are needed. The cytotoxic and anticancer effects of juglone and sodium selenite (NaSe) have been showed in various cancer cells. Objectives: In this study, it is aimed to investigate the synergistic effects of juglone and selenium on PANC-1 and BxPC-3 pancreatic cancer cells. Methods: Antimetastatic effects of juglone-NaSe were carried out by adhesion and invasion assays and the genes and protein expressions. Expression analysis of the CDH1, ITGB3 and COL4A3 genes and their proteins E-cadherin, β3 integrin and tumstatin which play role in metastasis and angiogenesis processes, were done by qPCR and immunohistochemical analysis, respectively. Results: Study findings have provided evidences that the juglone-selenium has a cytotoxic and dose dependent suppressive effect on invasion and metastasis in PANC-1 and BxPC-3 cells. Conclusion: The juglone-NaSe has the potential to be a promising agent especially to inhibit invasion and metastasis in pancreatic cancer treatment. However, more in depth studies are needed to more clearly demonstrate the effects of juglone-selenium. Keywords: Pancreatic cancer cell lines; juglone-selenium; invasion; metastasis

Impact of obstructive sleep apnoea on left ventricular mass and global function

Obstructive sleep apnoea syndrome (OSAS) might be a cause of heart failure. The present study aimed to assess left ventricular mass and myocardial performance index (MPI) in OSAS patients. A total of 67 subjects without any cardiac or pulmonary disease, referred for evaluation of OSAS, had overnight polysomnography and echocardiography. According to apnoea-hypopnoea index (AHI), subjects were classified into three groups: mild OSAS (AHI: 5-14; n=16), moderate OSAS (AHI: 15-29; n=18), and severe OSAS (AHI: ≥30; n=33). Thickness of interventricular septum (IVS) and posterior wall (LVPW) were measured by M-mode, along with left ventricular mass (LVM) and LVM index (LVMI). Left ventricular MPI was calculated as (isovolumic contraction time+isovolumic relaxation time)/aortic ejection time by Döppler echocardiography. There were no differences in age or body mass index among the groups, but blood pressures were higher in severe OSAS compared with moderate and mild OSAS. In severe OSAS, thickness of IVS (11.2 ± 1.1 mm), LVPW (11.4 ± 0.9 mm), LVM (298.8 ± 83.1 g) and LVMI (144.7 ± 39.8 g·m-2) were higher than in moderate OSAS (10.9 ± 1.3 mm; 10.8 ± 0.9 mm; 287.3 ± 74.6 g; 126.5 ± 41.2 g·m-2, respectively) and mild OSAS (9.9 ± 0.9 mm; 9.8 ± 0.8 mm; 225.6 ± 84.3 g; 100.5 ± 42.3 g·m-2, respectively). In severe OSAS, MPI (0.64 ± 0.14) was significantly higher than in mild OSAS (0.50 ± 0.09), but not significantly higher than moderate OSAS (0.60 ± 0.10). In conclusion, severe and moderate obstructive sleep apnoea syndrome patients had higher left ventricular mass and left ventricular mass index, and also left ventricular global dysfunction. Copyright©ERS Journals Ltd 2005

Effect of Nasal Continuous Positive Airway Pressure in Men on Global Left Ventricular Myocardial Performance in Patients With Obstructive Sleep Apnea Syndrome

The influence of obstructive sleep apnea syndrome (OSAS) on left ventricular function remains controversial. We examined the influence of OSAS on global left ventricular function using the myocardial performance index (Tei index) and plasma brain natriuretic peptide (BNP) level and investigated the effect of nasal continuous positive airway pressure (nCPAP) on these parameters. We obtained echocardiographic indexes including the Tei index and BNP concentrations from 27 patients with OSAS whose mean apnea--hypopnea index was 42.2 ± 21.5 events/hour and who were undergoing nCPAP and from 22 control subjects. We defined global left ventricular dysfunction (GLVD) as a Tei index ?0.50 and high BNP as ?20 pg/ml. Compared with controls, the Tei index of patients with OSAS was significantly increased (p <0.01) and prevalence of GLVD was high (19%, p <0.05). The correlation between the Tei index and apnea--hypopnea index was significant (r = 0.447, p <0.05). Although BNP levels were higher in patients with OSAS than in controls, the difference did not reach significance. BNP level was high in 37% of patients with OSAS and in only 9% of controls (p <0.05). The Tei index of patients with OSAS was significantly decreased after 1 month and 3 months of nCPAP (p <0.01), and prevalence of GLVD significantly decreased from 19% to 4% (p <0.05). In contrast, BNP significantly decreased at 3 months after nCPAP (p <0.05). In conclusion, patients with moderate to severe OSAS frequently have impaired global left ventricular myocardial performance, which can be reversed at the early stage after starting nCPAP.Without Table

Nasal continuous positive airway pressure improves myocardial perfusion reserve and endothelial-dependent vasodilation in patients with obstructive sleep apnea

<p>Abstract</p> <p>Background</p> <p>Obstructive sleep apnea (OSA) has been associated with cardiovascular disease (CVD), but whether OSA is an independent risk factor for CVD is controversial. The purpose of this study is to determine if patients with OSA have subclinical cardiovascular disease that is detectable by multi-modality cardiovascular imaging and whether these abnormalities improve after nasal continuous positive airway pressure (nCPAP).</p> <p>Results</p> <p>Of the 35 consecutive subjects with newly diagnosed moderate to severe OSA recruited from the Stanford Sleep Disorders Clinic, 20 patients were randomized to active vs. sham nCPAP. Active nCPAP was titrated to pressures that would prevent sleep disordered breathing based on inpatient polysomnography. OSA patients had baseline vascular function abnormalities including decreased myocardial perfusion reserve (MPR), brachial flow mediated dilation (FMD) and nitroglycerin-induced coronary vasodilation. Patients randomized to active nCPAP had improvement of MPR (1.5 ± 0.5 vs. 3.0 ± 1.3, p = 0.02) and brachial FMD (2.5% ± 5.7% vs. 9.0% ± 6.5%, p = 0.03) after treatment, but those randomized to sham nCPAP showed no significant improvement. There were no significant changes seen in chamber sizes, systolic and diastolic function, valvular function and coronary vasodilation to nitroglycerin.</p> <p>Conclusions</p> <p>Patients with moderate to severe OSA had decreased MPR and brachial FMD that improved after 3 months of nCPAP. These findings suggest that relief of apnea in OSA may improve microvascular disease and endothelial dysfunction, which may prevent the development of overt cardiovascular disease. Further study in a larger patient population may be warranted.</p

Effect of CPAP on QT interval dispersion in obstructive sleep apnea patients without hypertension.

OBJECTIVES: Delayed cardiac repolarization leading to prolongation of the QT interval is a well-characterised precursor of arrhythmias. Obstructive sleep apnea (OSA) might cause arrhythmias, since QT corrected interval dispersion (QTcd) is increased in these patients. We aimed to determine the effect of nasal continuous positive airway pressure (CPAP) therapy on QTcd in OSA patients without hypertension. METHODS: An overnight polysomnography (PSG) and a standard 12-lead electrocardiogram (ECG) were performed on 49 subjects without hypertension, diabetes mellitus, cardiac or pulmonary disease or any hormonal, hepatic, renal or electrolyte disorders. In 29 moderate-severe OSA (apnea-hypopnea index: AHI15) patients, QTd (defined as the difference between the maximum and minimum QT interval) and QTcd were calculated using the Bazzet formula at baseline and after six months of CPAP therapy. RESULTS: Eighteen patients were compliant with nasal CPAP, and mean age was 46.5+/-4.9 years. Patients had high body mass index (BMI: 30.6+/-4.0 kg/m(2)), but there was no change in either BMI or blood pressure after six months. A strong positive correlation was shown between QTcd and AHI (p<0.001, r=0.913). The QTcd at baseline (54.5+/-8.7 ms) significantly decreased after CPAP therapy (35.5+/-4.2 ms, p<0.001), although it did not significantly change in 11 non-compliant patients. CONCLUSION: In OSA patients without hypertension, CPAP therapy improves the inhomogeneity of repolarization via a significant decrease in QTcd

failure

Non-invasive mechanical ventilation (NIMV) therapy in patients with acute heart failure (HF) improves left ventricular functions via decreasing left ventricular afterload and reduces intubation rate and short-term mortality. In patients with chronic HF, NIMV therapy eliminates central and obstructive apneas and Cheyne-Stokes respiration, and improves morbidity. There are essentially three modes of NIMV that are used in the treatment of HF: Continuous positive airway pressure (CPAP), bilevel positive airway pressure (BIPAP) and adaptive servo-ventilation (ASV). Hereby, NIMV therapy in patients with acute and chronic HF is reviewed as well as methods, indications, effectiveness and complications. (Anadolu Kardiyol Derg 2012; 12: 261-8