Heart Care Info - Heart Disease Prevention & Treatment

Phosphodiesterase 5 inhibition with sildenafil reverses exercise oscillatory breathing in chronic heart failure: a long-term cardiopulmonary exercise testing placebo- ...

M Guazzi, M Vicenzi, R Arena - ... Journal of Heart Failure, 2012 - Aims Exercise oscillatory breathing (EOB) is a ventilatory abnormality that occurs in∼ 20% of heart failure (HF) patients and carries a very unfavourable prognosis. Pulmonary vasoconstriction has been suggested to be involved in this disorder. We hypothesized that ...

Methods and results Among 122 HF cases, 32 presented with EOB during cardiopulmonary exercise testing (CPX) and were randomized to receive placebo (n = 16) or sildenafil (n = 16) at the dose of 50 mg three times a day, in addition to their current antifailure treatment. CPX-derived variables and pulmonary haemodynamics were assessed at 6 and 12 months. Sildenafil reversed EOB in 87% of patients at 6 months and 93% at 1 year, respectively (P < 0.01). This effect was accompanied by an improvement in functional performance (peak VO2; from 9.6 to 12.4 and 13.2 m L/min/kg; P < 0.01) and exercise ventilation efficiency (ventilation to CO2 production slope; from 41.1 to 32.7 and 31.5; P < 0.01). Chronic treatment with PDE5 inhibition significantly decreased pulmonary capillary wedge pressure (from 21 to 14 and 14 mm Hg), mean pulmonary artery pressure (PAP; from 34.8 to 23 and 24 mm Hg), and pulmonary vascular resistance (PVR; from 360 to 270 and 266 dyne/s/cm5) compared with placebo (P < 0.01 for each comparison). On exploratory analysis, there was a correlation between PAP and PVR and the decrease in EOB in the treatment group. Placebo did not alter any of the aforementioned variables.