TY - BOOK AU - Dooley, Daniel J AU - McNamara, Martin J AU - Sayanlar, Jason J AU - Srichai, Monvadi B AU - Taylor, Allen J TI - A randomized pilot study on the effect of niacin on pulmonary arterial pressure SN - 1745-6215 PY - 2015/// KW - *Antihypertensive Agents/tu [Therapeutic Use] KW - *Arterial Pressure/de [Drug Effects] KW - *Hypertension, Pulmonary/dt [Drug Therapy] KW - *Niacin/tu [Therapeutic Use] KW - *Pulmonary Artery/de [Drug Effects] KW - *Vasodilator Agents/tu [Therapeutic Use] KW - Aged KW - Aged, 80 and over KW - Antihypertensive Agents/ae [Adverse Effects] KW - District of Columbia KW - Double-Blind Method KW - Echocardiography, Doppler KW - Female KW - Humans KW - Hypertension, Pulmonary/pp [Physiopathology] KW - Hypertension, Pulmonary/us [Ultrasonography] KW - Male KW - Middle Aged KW - Niacin/ae [Adverse Effects] KW - Pilot Projects KW - Pulmonary Artery/pp [Physiopathology] KW - Pulmonary Artery/us [Ultrasonography] KW - Time Factors KW - Treatment Outcome KW - Vasodilator Agents/ae [Adverse Effects] KW - Ventricular Function, Right/de [Drug Effects] KW - Ventricular Pressure/de [Drug Effects] KW - MedStar Heart & Vascular Institute KW - Journal Article KW - Randomized Controlled Trial KW - Research Support, Non-U.S. Gov't N1 - Available online through MWHC library: 2006 - present N2 - BACKGROUND: Niacin induces the release of vasodilating prostaglandins, for which receptors are present within the pulmonary arterial circulation. We hypothesized that immediate-release niacin would reduce right ventricular systolic pressure in patients with pulmonary hypertension in a randomized, double-blinded, single-dose provocation study; CONCLUSIONS: A single dose of immediate-release niacin (100 mg or 500 mg) had no significant effect on RVSP 1 hour post administration. A nonsignificant dose-dependent trend for a modest reduction in RVSP, most notable in the 500 mg group, was noted. (ISRCTN number 12353191, registered April 23, 2015); METHODS: We recruited inpatient subjects with a Doppler echocardiogram showing a peak tricuspid regurgitation (TR) jet velocity of 2.7 m/s or greater, and who were free of known pulmonary vascular disease. Subjects were randomized in a 1:2:2 ratio to receive a single dose of either placebo, niacin 100 mg or niacin 500 mg, respectively. TR jet velocities were measured immediately before, and 1 hour post dose, corresponding to peak niacin absorption and prostaglandin release. The primary endpoint was the change in mean TR jet velocity measured over ten successive cardiac cycles; RESULTS: The baseline mean estimated right ventricular systolic pressure (RVSP) for all 49 subjects (25 male) was 51.9+/-12.1 mm Hg. The primary endpoint of mean change in TR jet velocity was 0.016+/-0.065 m/s in the placebo group, compared to -0.017+/-0.065 m/s with niacin 100 mg, and -0.063+/-0.038 m/s with niacin 500 mg (P=0.63). The change in maximum estimated RVSP across the three drug groups was 0.2+/-1.6 mm Hg, -1.3+/-1.8 mm Hg and -2.2+/-1.2 mm Hg (P=0.62). In exploratory pairwise analysis in the high-dose niacin group (500 mg), the reduction in mean RVSP was from 50.9+/-9.4 mm Hg to 48.7+/-10.0 mm Hg (P=0.09) UR - http://dx.doi.org/10.1186/s13063-015-1013-6 ER -