Balloon Pulmonary Angioplasty in Chronic Thromboembolic Pulmonary Hypertension: New Horizons in the Interventional Management of Pulmonary Embolism

Imaging of chronic thromboembolic pulmonary hypertension before, during and after balloon pulmonary angioplasty

Balloon pulmonary angioplasty (BPA) has recently been elevated as a class I recommendation for the treatment of inoperable or residual chronic thromboembolic pulmonary hypertension (CTEPH). Proper patient selection, procedural safety, and post-procedural evaluation are crucial in the management of these patients, with imaging work-up playing a pivotal role. Understanding the diagnostic and therapeutic imaging algorithms of CTEPH, the imaging features of patients amenable to BPA, all imaging findings observed during and immediately after the procedure and the changes observed during the follow-up is crucial for all interventional radiologists involved in the care of patients with CTEPH. This article illustrates the imaging work-up of patients with CTEPH amenable to BPA, the imaging findings observed before, during and after BPA, and provides a detailed description of all imaging modalities available for CTEPH evaluation.

Application of DynaCT angiographic reconstruction in balloon pulmonary angioplasty

OBJECTIVES

To investigate the feasibility and accuracy of balloon pulmonary angioplasty (BPA) using DynaCT angiographic reconstruction guidance.

METHODS

Thirty-four BPAs (23 CTEPH patients) targeting 175 pulmonary arteries were included. Eleven BPAs (2D group) were guided by DSA two-dimensional angiography. Another twenty-three BPAs (3D group) were guided using DynaCT angiographic reconstruction. The volume rendering (VR) method was used to obtain a three-dimensional image of the blood vessels. This image was used as a reference to continue BPA treatment under the guidance of vascular three-dimensional reconstruction technology. Procedure durations and radiation exposure data were compared between the two groups using Mann-Whitney U test.

RESULTS

Using the DynaCT angiographic reconstruction technique, more target vessels were treated in a single BPA procedure (5.83 ± 2.33 vs 3.73 ± 1.10 vessels per BPA, p = 0.008) in a shorter operation time (3.58 ± 0.61 vs 4.49 ± 0.91 h, p = 0.002). Overall, the dose area product (DAP) was significantly higher for the 2D group than for the 3D group (13,901.82 ± 5549.69 vs 4682.82 ± 1950.64, p < 0.001). The use of the DynaCT angiographic reconstruction technique to guide BPA required a lower dose of contrast agent (225.22 ± 48.70 vs 292.73 ± 76.82 mL, p = 0.013) and less radiation exposure.

CONCLUSIONS

The use of DynaCT angiographic reconstruction guidance in patients undergoing BPA is feasible and accurate. Images of DynaCT angiographic reconstruction may be beneficial for optimizing the operative process in BPA with reduced radiation exposure.

KEY POINTS

• BPA guidance by DynaCT angiographic reconstruction is feasible and accurate. • DynaCT angiographic reconstruction may be beneficial for optimizing the operative process. • DynaCT angiographic reconstruction can reduce patient radiation dose due to multi-times of BPA sessions.

Speckle tracking for predicting outcomes of balloon pulmonary angioplasty in patients with chronic thromboembolic pulmonary hypertension

BACKGROUND

Right ventricular (RV) function is a prognostic marker of chronic thromboembolic pulmonary hypertension (CTEPH). We used two-dimensional (2D) speckle-tracking echocardiography (STE) to evaluate the therapeutic effects of balloon pulmonary angioplasty (BPA) in CTEPH patients.

METHODS

A total of 46 CTEPH patients who underwent 2D STE before and after BPA were enrolled in this retrospective study. The following RV functional parameters were measured: tricuspid annular plane systolic excursion (TAPSE), right ventricular fractional area change (RVFAC), RV index of myocardial performance (RIMP), and free wall longitudinal strain (RVFWLS). Satisfactory BPA was defined as mean pulmonary arterial pressure (mPAP) <25 mm Hg or improvement in mPAP > 10 mm Hg after BPA. Patients were divided into two groups according to mPAP values: group I had satisfactory BPA outcomes; group Ⅱ had unsatisfactory BPA outcomes. The area under the curve (AUC) of the receiver operating characteristic (ROC) curve was used to determine the optimal cutoff values and the ability of RVFWLS to predict successful BPA outcomes.

RESULTS

After BPA, SPAP measured by echocardiography (SPAP_echo ) and RIMP decreased, but TAPSE, RVFAC, and RVFWLS increased. Before BPA, group Ⅰ had significantly better RV function than group Ⅱ. Multifactor logistic regression analysis identified RVFWLS as an independent factor associated with satisfactory BPA outcomes. The optimal cutoff value for RVFWLS in predicting satisfactory BPA outcomes was -12.2%.

CONCLUSIONS

Balloon pulmonary angioplasty improves RV function in CTEPH patients. RVFWLS is a valuable noninvasive tool with which to assess the treatment effects of BPA. CTEPH patients with lower RVFWLS may have limited benefit from BPA.

Surgical and Percutaneous Interventions for Chronic Thromboembolic Pulmonary Hypertension

The treatment of chronic thromboembolic pulmonary hypertension has expanded considerably. The ability to endarterectomize chronic thromboembolic material, the availability of pulmonary hypertension medical therapy to treat inoperable chronic thromboembolic pulmonary hypertension and/or residual pulmonary hypertension, and the rebirth of pulmonary balloon angioplasty have changed the management landscape. Patient selection requires a multidisciplinary evaluation at an experienced center. What is inoperable chronic thromboembolic pulmonary hypertension to one group may be operable chronic thromboembolic pulmonary hypertension to another. The ultimate challenge then becomes which intervention provides the optimal long-term outcome for any individual patient.