Relationship between pulmonary arterial resistance and compliance among patients with pulmonary arterial hypertension and congenital heart disease

Jun Muneuchi; Yusaku Nagatomo; Mamie Watanabe; Kunihiko Joo; Tatsushi Onzuka; Yoshie Ochiai; Kunitaka Joo

doi:10.1016/j.jtcvs.2016.03.080

Relationship between pulmonary arterial resistance and compliance among patients with pulmonary arterial hypertension and congenital heart disease

J Thorac Cardiovasc Surg. 2016 Aug;152(2):507-13. doi: 10.1016/j.jtcvs.2016.03.080. Epub 2016 Apr 13.

Authors

Jun Muneuchi¹, Yusaku Nagatomo², Mamie Watanabe², Kunihiko Joo³, Tatsushi Onzuka³, Yoshie Ochiai³, Kunitaka Joo²

Affiliations

¹ Department of Pediatrics, Japan Community Healthcare Organization, Kyushu Hospital, Kitakyushu, Fukuoka, Japan. Electronic address: jmune@msn.com.
² Department of Pediatrics, Japan Community Healthcare Organization, Kyushu Hospital, Kitakyushu, Fukuoka, Japan.
³ Department of Cardiovascular Surgery, Japan Community Healthcare Organization, Kyushu Hospital, Kitakyushu, Fukuoka, Japan.

PMID: 27189891
DOI: 10.1016/j.jtcvs.2016.03.080

Abstract

Background: It is unknown whether changes in pulmonary arterial resistance (Rp), pulmonary arterial compliance (Cp), and the product of Rp and Cp (the RC time) in patients with pulmonary arterial hypertension (PAH) are related to an increase in pulmonary blood flow. The aim of this study is to clarify relationships between these parameters before and after corrective surgery among patients with PAH and congenital heart disease.

Methods: We performed cardiac catheter examinations and compared Rp, Cp, and the RC time before and after corrective surgery in 100 infants (53 boys) with PAH related to ventricular septal defect.

Results: Median age at surgery was 2.9 (0.6-28.5) months. Preoperative values of the ratio of pulmonary to systemic blood flow (Qp/Qs), systolic pulmonary arterial pressure (PAP), Rp, Cp, and the RC time were 3.5 (2.7-4.3), 65 (56-70) mm Hg, 2.18 (1.64-3.19) Wood unit/m(2), 2.67 (2.01-3.38) mL/mm Hg/m(2), and 0.36 (0.31-0.40) seconds, respectively. Postoperative systolic PAP, Cp, and the RC time were significantly decreased to 26 (23-29) mm Hg, 1.96 (1.77-2.26) mL/mm Hg/m(2), and 0.31 (0.26-0.36) seconds, respectively, although Rp remained unchanged at 2.53 (2.06-3.31) Wood unit/m(2). The relationship between Rp and Cp was inversely related before and after surgery, and the Rp-Cp coupling curve was shifted downward after surgery. In addition, lower preoperative Cp (partial regression coefficient = -3.35; P = .001) and preterm delivery (partial regression coefficient = 6.28; P = .02) were independently related to postoperative higher systolic PAP.

Conclusions: Rp-Cp coupling depends on both the amount of pulmonary blood flow and the condition of the pulmonary vasculature. Lower preoperative Cp is an independent predictive factor to predict higher postoperative pulmonary systolic pressure leading to an increase in right ventricular workload. It is necessary to assess Rp-Cp coupling before surgery among patients with PAH related to congenital heart disease.

Keywords: RC time constant; compliance; left-to-right shunt; pulmonary arterial hypertension; resistance.

MeSH terms

Arterial Pressure*
Cardiac Catheterization
Cardiac Surgical Procedures* / adverse effects
Compliance
Female
Heart Septal Defects, Ventricular / complications
Heart Septal Defects, Ventricular / diagnostic imaging
Heart Septal Defects, Ventricular / physiopathology
Heart Septal Defects, Ventricular / surgery*
Humans
Hypertension, Pulmonary / complications
Hypertension, Pulmonary / diagnosis
Hypertension, Pulmonary / physiopathology*
Infant
Infant, Newborn
Male
Pulmonary Artery / physiopathology*
Pulmonary Circulation
Recovery of Function
Time Factors
Treatment Outcome
Vascular Resistance*
Vascular Stiffness*