Abstract 2911: Effect of Pulmonary Hypertension on Ventricular Mechanics: A New Strain Measurement Method
Background: Right ventricular (RV) function is believed to greatly influence left ventricular (LV) function in many cardiac and cardiopulmonary diseases.
Methods: We studied 24 patients with pulmonary arterial hypertension (pHTN) and 10 patients with normal RV and LV function. Clinical classifications included functional subgroups of pHTN: class 1(5 patients), 2 (7patients), 3(6patients), and 4 (6patients). Images were obtained with a Siemens Sequoia at basal and apical LV short axis. RV pressures; ph, pO2 and pCO2 were obtained in all patients confirming the diagnosis and classification of pHTN. Vector Velocity Iimaging (Siemens) was used for offline analysis of LV circumferential strain (circ ε) and circumferential strain rate (circ SR).
Results: At baseline, LV circ ε was measured at 24.3% ± 8% and circ SR at 2.6%/sec ± 0.4/sec in all 10 healthy subjects, while in all patients with class 1 to class 4 pHTN a significant decrease in circ ε to 16.4% ± 6% and circ SR to 1.7%/sec ± 0.6%/sec could be found. Noticeably the circ ε was highest in the inferior (28.5% ± 5%) and anterior septal (25.6% ± 6%) area in the control group, while in all patients with pHTN the inferior septal circ ε (14.3% ± 4%) and anterior septal circ ε (12.6% ± 8%) was significantly decreased (p < 0.05). Further an inverse relationship between RV pressure and peak LV systolic circ εcould be found. Patients with low LVEF (25%–35%) and high RV pressures showed significant decrease in peak systolic LV circ ε to 10.8% ± 6% and circ SR to 1.0%/sec ± 0.6%/sec.
Conclusions: LV circ SR decreased with RV pressure load and septal flattening. VVI detected the global and regional septal abnormality.