Abstract 12497: Hemodynamic Effect of Diuretic Therapy on Post-capillary Pulmonary Hypertension in Chronic Heart Failure
Background: Post-capillary pulmonary hypertension (pc-PH) in left-sided heart failure is classified as passive (transpulmonary pressure gradient: TPG ≤12mmHg) or reactive (TPG >12mmHg). We aimed to evaluate the hemodynamic effect of diuretic therapy in different forms of heart failure, non-PH, passive pc-PH, and reactive pc-PH.
Methods: Fifty-four patients (71 ± 11 years, NYHA class 3.0 ± 0.6, and left ventricular ejection fraction 41 ± 17 %) with chronic heart failure and excess fluid retention orally received either tolvaptan (7.5 mg/day, n =31), a selective vasopressin V2 receptor blocker, or furosemide (20mg/day, n =23) for 7 days. Hemodynamic measurements were performed using Swan-Ganz catheter before and after 7-day diuretic therapy.
Results: There were 12 patients with non-PH, 27 with passive pc-PH, and 15 with reactive pc-PH. Body weight decreased after 7-day diuretic therapy in all 3 groups. Although mean pulmonary artery wedge pressure (mPCWP), mean pulmonary atrial pressure (mPAP), and mean right atrial pressure (mRAP) significantly decreased in all 3 groups. Cardiac index remained unchanged in all 3 groups. Pulmonary vascular resistance index (PVRI) was significantly lowered by 7-day diuretic therapy only in patients with reactive pc-PH, irrespective of whether they received tolvaptan or furosemide. In addition, there was no relationship between changes in PVRI and changes in mPCWP in this patient group, suggesting reduction of pre-capillary pressure does not contribute solely to the reduction of pulmonary vascular tone in reactive pc-PH subtype.
Conclusions: The reduction in cardiac preload is likely to contribute to the decreased in pulmonary vascular tone in reactive pc-PH subtype. These findings may shed new light on the causal mechanism of reactive pc-PH in patients with heart failure.
- © 2013 by American Heart Association, Inc.