Assessment of Pulmonary Congestion During Cardiac Hemodynamic Stress Testing

Assessment of Pulmonary Congestion During Cardiac Hemodynamic Stress Testing

The aim of this study is to utilize lung ultrasound to detect the development of extravascular lung water in patients undergoing clinically indicated invasive hemodynamic exercise stress testing for symptomatic shortness of breath. The study will correlate the lung ultrasound findings with cardiac hemodynamics and measurements of extravascular lung water in an effort to better understand the pathophysiology of exertional dyspnea.

Exercise induced elevation of left ventricular (LV) filling pressures can be the source of chronic dyspnea. Ultimately, high LV filling pressure leads to the development of extravascular lung water (EVLW) which can cause symptoms of dyspnea. Lung ultrasound (LUS) is a highly feasible, non-invasive procedure that is extremely sensitive for detecting EVLW. The sonographic signature of EVLW is a reverberation artifact called a "B-Line". The study will evaluate the etiology of sonographic B-Lines using invasive hemodynamic catheterization while simultaneously measuring the amount of EVLW present during exercise stress testing using transpulmonary thermodilution. The study aim is to demonstrate that the severity of EVLW, assessed by number of B-Lines, will correlate with LV filling pressures. In addition, the study will test the hypothesis that patients demonstrating dynamic increases in sonographic B-Lines with exercise will also display more severe symptoms of dyspnea, altered ventilatory mechanics (higher ratio of minute ventilation to carbon dioxide production (VE/VCO2)), and reduced aerobic capacity (lower peak oxygen consumption (VO2)).

Inclusion Criteria:

• All adult patients (≥18 years) who are referred for invasive cardiac hemodynamic assessment
• Patients who have the capacity to understand and consent for the research study

Exclusion Criteria:

• Patients with known interstitial lung disease or pulmonary fibrosis