Doppler‐derived pulmonary pulse transit time measurements in chronic obstructive pulmonary disease: Reproducibility and cardiopulmonary function

• Published in: Echocardiography (Mount Kisco, N.Y.) Vol. 41; no. 5; pp. e15821 - n/a
• Main Authors: Löffler, Friederike, Westhoff‐Bleck, Mechthild, Welte, Tobias, Park, Da‐Hee, Olsson, Karen M, Behrendt, Lea, Klimeš, Filip, Bauersachs, Johann, Wacker, Frank, Pöhler, Gesa Helen
• Format: Journal Article
• Language: English
• Published: United States 01.05.2024
• Subjects: Aged; Blood Flow Velocity - physiology; COPD; diastolic right heart function; echocardiography; Echocardiography, Doppler - methods; Female; Humans; Male; Middle Aged; Prospective Studies; Pulmonary Disease, Chronic Obstructive - diagnostic imaging; Pulmonary Disease, Chronic Obstructive - physiopathology; Pulse Wave Analysis - methods; Reproducibility of Results; Respiratory Function Tests - methods; diastolic right heart function; echocardiography; COPD
• ISSN: 0742-2822; 1540-8175; 1540-8175
• DOI: 10.1111/echo.15821

Introduction Doppler‐derived pulmonary pulse transit time (pPTT) is an auspicious hemodynamic marker in chronic pulmonary diseases. The aim is to compare four distinct pPTT measurements and its relation to right cardiac and pulmonary function. Methods Prospectively, 25 chronic obstructive pulmonary disease (COPD) patients (four patients excluded) and 32 healthy subjects underwent repeated distinct pPTT measurements, standard echocardiography, and pulmonary function testing on the same day. pPTT was defined as the interval from the R or Q‐wave in the electrocardiogram to the corresponding pulse wave Doppler peak late systolic (S) 2 or diastolic (D) pulmonary vein flow velocity (pPTT R‐S, Q‐S, R‐D, Q‐D). Reproducibility was assessed using Bland–Altman analysis, coefficient of variation (COV), intraclass correlation coefficient (ICC), and power calculations. Associations with right ventricular RV tissue and pulse wave Doppler velocities (RV E', RV S', RV A', RV E, RV A, RV E/E', RV E/A), TAPSE, right ventricular fractional area change, left ventricular systolic and diastolic function (LV ejection fraction, E, A, E/A, E/E', septal E', lateral E'), LA diameters, as well as forced expiratory volume in 1 s, forced vital capacity (FVC) predicted (%), and in liters were analyzed. Results There was no significant difference and no bias between pPTT measures (p range: .1–.9). COV was in COPD 1.2%–2.3%, in healthy subjects 1.0%–3.1%. ICC ranged from .92 (COPD) to .96 (healthy subjects). In COPD significant correlations were found for pPTT R‐S, Q‐S and R‐D with RV E`, (all > ρ: .49, < p = .0364), pPTT R‐S, Q‐S with RV E/E` (both > ρ: .49, < p = .0291), pPTT Q‐S with RV S´ (ρ: .58, p = .0134), RV A (ρ: .59, p = .0339) and heart rate > ρ: −.39, < p = .0297). pPTT R‐S, R‐D showed significant correlations with FVC predicted (%) (ρ: .48 p = .0224) and FVC (l) (ρ:.47 p = .0347). Conclusions All pPTT measures exhibited high reproducibility. In COPD patients pPTT measures correlate with diastolic right ventricular function. Defining Q as starting point seems clinically advantageous considering electromechanical desynchrony in patients with conduction disorders. Four distinct Doppler‐derived pulmonary pulse transit times (pPTT) were measured in both chronic obstructive pulmonary disease (COPD) patients and healthy controls, demonstrating high reproducibility across all measures. Significant correlations were observed between pPTT and diastolic right ventricular function in COPD patients, as well as with pulmonary function test results.