Right Ventricular Hemodynamics Using Cardiac MRI in Patients COPD and OSA
Right Ventricular Hemodynamics Using Cardiac MRI in Patients COPD and OSA
The coexistence of chronic obstructive pulmonary disease (COPD) and obstructive sleep apnea
 (OSA) in the same patient has been termed overlap syndrome, affecting 1% of the U.S.
 population.The investigators propose to conduct this study that aims: (1) to compare right
 and left ventricular hemodynamic parameters using cardiac magnetic resonance imaging (MRI) in
 overlap syndrome vs. COPD only and OSA only; (2) to compare the effects of bi-level positive
 airway pressure (BPAP) vs. nocturnal oxygen therapy (NOT) on right ventricular (RV)
 hemodynamics in overlap syndrome.

 This study will allow us to test the hypothesis: (1) Patients with overlap syndrome have more
 RV dysfunction than those with COPD only or OSA only; (2) treatment of both hypoxemia and
 hypercapnia during sleep will improve RV hemodynamics compared with treatment of hypoxemia
 alone in patients with overlap syndrome.
Despite the high prevalence of overlap syndrome, few data are available on its
 pathophysiology and clinical consequences of these patients. Overlap syndrome has recently
 been reported to have excess cardiovascular mortality compared with COPD alone. However, no
 study has evaluated the mechanisms of excess cardiovascular mortality in untreated overlap
 syndrome. In addition, no prospective, randomized, controlled data are currently available on
 treatment of overlap syndrome.

 This study is divided into two parts. The first part (Part 1) is a cross-sectional cohort
 study comparing subjects with overlap syndrome to those with COPD alone and those with OSA
 alone. Patients with COPD and OSA overlap syndrome will be evaluated by an overnight sleep
 study, cardiac MRI, serum inflammatory biomarker, urine catecholamine level, pulmonary
 function test, and questionnaires of sleep and health related quality of life. These
 measurement will be compared between overlap syndrome and control groups with either COPD or
 OSA alone.

 The second part (Part 2) of the study is a prospective, parallel-group, randomized,
 controlled pilot study examining the effect of BPAP (and nocturnal oxygen if needed) vs.
 nocturnal oxygen therapy alone in patients with overlap syndrome (20 subjects in each
 treatment arm). The same measurement done during Part 1 will be repeated to evaluate the
 treatment effects.
Inclusion Criteria:

 -  Both men and women with age more than 18 years.

 -  Known diagnosis of stable COPD (GOLD stage 2 or higher) or OSA.

 Exclusion Criteria:

 -  Already using continuous positive airway pressure (CPAP), BPAP device, or nocturnal
 oxygen.

 -  Known or suspected renal failure with estimated Glomerular filtration (GFR) <50
 ml/min/1.73 m2 or serum creatinine > 1.5 mg/dl.

 -  Chronic atrial fibrillation or frequent premature ventricular contraction (> 10 beats
 per hour)

 -  Women known to be pregnant or planning to be pregnant in next 6 months.

 -  Known contraindication to MRI: cardiac pacemaker, metallic heart valves, metallic
 implants, history of claustrophobia.

 -  If taking sildenafil or related drugs, unable to stop it within 48 hours of the study
 visit.

 -  Uncontrolled COPD or acute COPD exacerbation.

 -  Unstable cardiac diseases.

 -  Known chronic inflammatory diseases like lupus or active infection.