Regional Right Ventricular Abnormalities Implicate Distinct Pathophysiological Conditions in Patients With Chronic Thromboembolic Pulmonary Hypertension

Regional Right Ventricular Function Assessed by Intraoperative Three-Dimensional Echocardiography Is Associated With Short-Term Outcomes of Patients Undergoing Cardiac Surgery

Background

The assessment of right ventricular (RV) function in patients undergoing elective cardiac surgery is paramount for providing optimal perioperative care. The role of regional RV function assessment employing sophisticated state-of-the-art cardiac imaging modalities has not been investigated in this cohort. Hence, this study investigated the association of 3D echocardiography-based regional RV volumetry with short-term outcomes.

Materials and Methods

In a retrospective single-center study, patients undergoing elective cardiac surgery were included if they underwent 3D transesophageal echocardiography prior to thoracotomy. A dedicated software quantified regional RV volumes of the inflow tract, apical body and RV outflow tract employing meshes derived from 3D speckle-tracking. Echocardiographic, clinical and laboratory data were entered into univariable and multivariable logistic regression analyses to determine association with the endpoint (in-hospital mortality or the need for extracorporeal circulatory support).

Results

Out of 357 included patients, 25 (7%) reached the endpoint. Inflow RV ejection fraction (RVEF, 32 ± 8% vs. 37 ± 11%, p = 0.01) and relative stroke volume (rel. SV) were significantly lower in patients who reached the endpoint (44 ± 8 vs. 48 ± 9%, p = 0.02), while the rel. SV of the apex was higher (38 ± 10% vs. 33 ± 8%, p = 0.01). Global left and right ventricular function including RVEF and left ventricular global longitudinal strain did not differ. In univariable logistic regression, tricuspid regurgitation grade ≥ 2 [odds ratio (OR) 4.24 (1.66–10.84), p < 0.01], inflow RVEF [OR 0.95 (0.92–0.99), p = 0.01], inflow rel. SV [OR 0.94 (0.90–0.99), p = 0.02], apex rel. SV [OR 1.07 (1.02–1.13), p < 0.01] and apex to inflow rel. SV ratio [OR 5.81 (1.90–17.77), p < 0.01] were significantly associated with the endpoint. In a multivariable model, only the presence of tricuspid regurgitation [OR 4.24 (1.66–10.84), p < 0.01] and apex to inflow rel. SV ratio [OR 6.55 (2.09–20.60), p < 0.001] were independently associated with the endpoint.

Conclusions

Regional RV function is associated with short-term outcomes in patients undergoing elective cardiac surgery and might be helpful for optimizing risk stratification.

Regional Right Ventricular Abnormalities Implicate Distinct Pathophysiological Conditions in Patients With Chronic Thromboembolic Pulmonary Hypertension

Background

Right ventricular (RV) dysfunction is a prognostic factor for cardiovascular disease. However, its mechanism and pathophysiology remain unknown. We investigated RV function using RV‐specific 3‐dimensional (3D)‐speckle‐tracking echocardiography (STE) in patients with chronic thromboembolic pulmonary hypertension. We also assessed regional wall motion abnormalities in the RV and chronological changes during balloon pulmonary angioplasty (BPA).

Methods and Results

Twenty‐nine patients with chronic thromboembolic pulmonary hypertension who underwent BPA were enrolled and underwent right heart catheterization and echocardiography before, immediately after, and 6 months after BPA. Echocardiographic assessment of RV function included both 2‐dimensional‐STE and RV‐specific 3D‐STE. Before BPA, global area change ratio measured by 3D‐STE was significantly associated with invasively measured mean pulmonary artery pressure and pulmonary vascular resistance (r=0.671 and r=0.700, respectively). Dividing the RV into the inlet, apex, and outlet, inlet area change ratio showed strong correlation with mean pulmonary artery pressure and pulmonary vascular resistance before BPA (r=0.573 and r=0.666, respectively). Only outlet area change ratio was significantly correlated with troponin T values at 6 months after BPA (r=0.470), and its improvement after BPA was delayed compared with the inlet and apex regions. Patients with poor outlet area change ratio were associated with a delay in RV reverse remodeling after treatment.

Conclusions

RV‐specific 3D‐STE analysis revealed that 3D RV parameters were novel useful indicators for assessing RV function and hemodynamics in pulmonary hypertension and that each regional RV portion presents a unique response to hemodynamic changes during treatment, implicating that evaluation of RV regional functions might lead to a new guide for treatment strategies.