Elevated 1-h Post-load Plasma Glucose is Associated with Right Ventricular Morphofunctional Parameters in Hypertensive Patients

Purpose: Emerging data demonstrate that type 2 diabetes mellitus (T2DM) is associated with right ventricular (RV) dysfunction. A cutoff point of 155 mg/dL for the 1-hour (h) post-load plasma glucose, during oral glucose tolerance test (OGTT), identifies patients with normal glucose tolerance (NGT) at high risk to develop T2DM and cardiovascular (CV) disease. We investigated if 1-h post-load glucose may affect RV geometry and function in a group of never-treated hypertensive individuals.

Methods: We enrolled 446 Caucasian newly diagnosed hypertensive outpatients. All patients underwent an OGTT and a standard echocardiography. The tricuspid annular plane systolic excursion (TAPSE) and the RV fractional area change (RVFAC) were measured together with systolic pulmonary arterial pressure (s-PAP) and pulmonary vascular resistances (PVR). Insulin sensitivity was evaluated using the Matsuda index.

Results: Among all partecipants, 296 had NGT, 100 impaired glucose tolerance (IGT), and 50 T2DM. Considering the cutoff point of 155 mg/dl for 1-h glucose, NGT subjects were stratified into two groups: NGT < 155 (n = 207), NGT ≥ 155 (n = 89). Subjects NGT ≥ 155 presented a worse metabolic and inflammatory profile than NGT < 155. RV functional parameters (TAPSE, RVFAC, TAPSE/s-PAP, and TAPSE/PVR) were significantly reduced in NGT ≥ 155 subjects compared with NGT < 155 patients. On the contrary, s-PAP and PVR were significantly higher. At multiple regression analysis, 1-h glucose was the strongest predictor of TAPSE in NGT ≥ 155, IGT, and T2DM.

Conclusions: The presence of RV impairment in hypertensive NGT ≥ 155 subjects further complicates their CV burden and it may, at least in part, justify the worse clinical outcome in this setting of patients.