[Show abstract][Hide abstract] ABSTRACT: Abstract Untreated chronic obstructive pulmonary disease (COPD) co-existing with obstructive sleep apnea (OSA), also known as overlap syndrome, has higher cardiovascular mortality than COPD alone but its underlying mechanism remains unclear. We hypothesize that the presence of overlap syndrome is associated with more extensive right ventricular (RV) remodeling compared to patients with COPD alone. Adult COPD patients (GOLD stage 2 or higher) with at least 10 pack-years of smoking history were included. Overnight laboratory-based polysomnography was performed to test for OSA. Subjects with an apnea-hypopnea index (AHI) >10/h were classified as having overlap syndrome (n = 7), else classified as having COPD-only (n = 11). A cardiac MRI was performed to assess right and left cardiac chambers sizes, ventricular masses, and cine function. RV mass index (RVMI) was markedly higher in the overlap group than the COPD-only group (19 ± 6 versus 11 ± 6; p = 0.02). Overlap syndrome subjects had a reduced RV remodeling index (defined as the ratio between RVMI and RV end-diastolic volume index) compared to the COPD-only group (0.27 ± 0.06 versus 0.18 ± 0.08; p = 0.02). In the overlap syndrome subjects, the extent of RV remodeling was associated with severity of oxygen desaturation (R(2) = 0.65, p = 0.03). Our pilot results suggest that untreated overlap syndrome may cause more extensive RV remodeling than COPD alone.
[Show abstract][Hide abstract] ABSTRACT: OPINION STATEMENT: Sleep disordered breathing (SDB) is common in heart failure patients across the range of ejection fractions and is associated with adverse prognosis. Although effective pharmacologic and device-based treatment of heart failure may reduce the frequency or severity of SDB, heart failure treatment alone may not be adequate to restore normal breathing during sleep. Continuous positive airway pressure (CPAP) is the major treatment for SDB in heart failure, especially if obstructive rather than central sleep apnea (CSA) predominates. Adequate suppression of CSA by PAP is associated with a heart transplant-free survival benefit, although randomized trials are ongoing. Bilevel PAP (BPAP) may be as effective as CPAP in treating SDB and may be preferable over CPAP in patients who experience expiratory pressure discomfort. Adaptive (or auto) servo-ventilation (ASV), which adjusts the PAP depending on the patient's airflow or tidal volume, may be useful in congestive heart failure patients if CPAP is ineffective. Other therapies that have been proposed for SDB in congestive heart failure include nocturnal oxygen, CO(2) administration (by adding dead space), theophylline, and acetazolamide; most of which have not been systematically studied in outcome-based prospective randomized trials.
Current Treatment Options in Cardiovascular Medicine 09/2011; 13(6):506-16. DOI:10.1007/s11936-011-0145-6
[Show abstract][Hide abstract] ABSTRACT: This study sought to determine whether reduced pulmonary function in obstructive airway disease (OAD) is an independent risk factor for obstructive sleep apnea (OSA). This was a prospective observational study conducted at an outpatient pulmonary clinic. Adults with a known diagnosis of COPD/asthma were enrolled as OAD group. Family members without a history of COPD/asthma who accompanied these patients to the clinic were enrolled as a control group. The Berlin Questionnaire (BQ) was used to assess OSA risk in the OAD group and controls. Forced expiratory volume in 1 second (FEV(1) % predicted) was determined from spirometry. The subjects at high risk for OSA were referred for a full overnight polysomnogram (PSG). The prevalence of patients with a high risk of OSA was 55.2% in the OAD group, which was higher than in the controls (7.5%, p < 0.0001). OAD subjects had a higher body mass index (BMI) and larger neck circumference than controls (p < 0.01). There was no difference in FEV(1) % predicted between the OAD patients at high risk and low risk of OSA. On receiver operator curve (ROC) analysis, FEV(1) % predicted was not a significant predictor of high OSA risk. Using logistic regression, FEV(1) % predicted had no association with OSA risk. There was no correlation between FEV(1) % predicted and total apnea-hypopnea index (AHI), oxygen desaturation index, % time spent below oxygen saturation 90%, and mean oxygen saturation on multiple regression analysis. OSA appears to be common in patients with COPD or asthma in an urban outpatient pulmonary clinic. However, the high prevalence of OSA in OAD patients appears to be due to obesity, and reduced pulmonary function is not an independent risk factor for OSA.
Beiträge zur Klinik der Tuberkulose 02/2011; 189(1):37-41. DOI:10.1007/s00408-010-9270-3 · 2.27 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: We report an unusual clinical presentation of renal leiomyosarcoma. A woman, who received renal transplant from her mother, was diagnosed to have leiomyosarcoma in the donated kidney. The mother was found to have a right upper lobe lung mass 10 years later, which was diagnosed as leiomyosarcoma. It is possible that the mother had primary leiomyosarcoma of the donated kidney with micrometastases to the lung 10 years previously, which developed into a lesion in the donated kidney in her daughter. Ten years later, the slow-growing metastatic leiomyosarcoma developed into a lung mass.
[Show abstract][Hide abstract] ABSTRACT: Breathing disorders during sleep are common in congestive heart failure (CHF). Sleep-disordered breathing (SDB) in CHF can be broadly classified as 2 types: central sleep apnea with Cheyne-Stokes breathing, and obstructive sleep apnea. Prevalence of SDB ranges from 47% to 76% in systolic CHF. Treatment of SDB in CHF may include optimization of CHF treatment, positive airway pressure therapy, and other measures such as theophylline, acetazolamide, and cardiac resynchronization therapy. Periodic limb movements are also common in CHF.
The Medical clinics of North America 05/2010; 94(3):447-64. DOI:10.1016/j.mcna.2010.02.009 · 2.61 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: The primary symptom of circadian rhythm sleep disorders (CRSDs) is the inability to sleep during the desired sleep time. CRSDs are divided into two broad classes: (i) disorders not related to forced alterations of the sleep–wake schedule or light–dark cycle (including advanced sleep phase disorder [ASPD], delayed sleep phase disorder [DSPD], non-entrained type [NET], and irregular sleep–wake rhythm [ISWR]); and (ii) disorders related to forced alterations of the sleep–wake schedule or light–dark cycle (including shift work sleep disorder [SWSD], jet lag disorder [JLD], and CRSDs related to diseases and medications). DSPD and ASPD are the common primary circadian rhythm disorders. We discuss the recent developments in the pathogenesis, diagnosis, and management of CRSDs.