Pulmonary artery angioplasty improves subjective symptoms and hemodynamics at a tolerable level in patients with chronic thromboembolic pulmonary hypertension, according to a small study published online November 6, 2012, ahead of print in Circulation: Cardiovascular Interventions. While the procedure does not produce any immediate hemodynamic improvement, a measurable therapeutic effect is seen after several months.

Toru Satoh, MD, of Kyorin University School of Medicine (Tokyo, Japan), and colleagues looked at 29 patients with chronic thromboembolic pulmonary hypertension who underwent angioplasty for pulmonary lesions from January 2009 to December 2011. One patient had a wiring perforation as a complication of the procedure and died 2 days later. The remaining 28 patients (average age 61.9 years; 78.6% women) were analyzed immediately after the procedure and 6 months later.

Procedural Effect Good, Not Immediate

A total of 51 procedures were performed. No hemodynamic improvements were seen immediately after the procedure (table 1).

Table 1. Acute Hemodynamic Effects

At 6 months, however, there were improvements from baseline in NYHA functional class (P < 0.01) and plasma BNP levels (306 ± 271 pg/mL vs. 98 ± 197 pg/mL; P < 0.01).

Hemodynamic parameters also improved by 6-month follow-up. Pulmonary arterial pressure decreased from 45.3 ± 9.8 mm Hg to 31.8 ± 10.0 mm Hg, and cardiac output rose from 3.6 ± 1.2 L/min to 4.6 ± 1.7 L/min (P < 0.01 for both). These results were consistent in patients who maintained their original medications. However, comparison of the hemodynamics between baseline and follow-up in 4 patients who received augmented targeted therapy demonstrated only an improvement in mean pulmonary arterial pressure (P < 0.05).

Overall, pulmonary edema was the chief complication, occurring after 27 procedures (53%). Other complications were a dissection in 1 of the targeted pulmonary arteries just after balloon dilatation and an extravascular leak following dilatation.

Many Advantages

“The study demonstrates that [pulmonary angioplasty] is clinically effective for the treatment of [chronic thromboembolic pulmonary hypertension],” Dr. Satoh and colleagues write.

Even so, the authors acknowledge that the procedure “does not produce an immediate therapeutic effect” and that a “certain amount of time is required after [angioplasty] before maximal therapeutic effect on functional ability and hemodynamics is measurable.”

The main advantages to pulmonary artery angioplasty, they note, are that it can treat distal narrow lesions not accessible by pulmonary endarterectomy and is less invasive and does not require anesthesia. Moreover, the procedure stands to become widespread in that only minimal training will be needed for operators at institutions with experience in treating pulmonary hypertension and performing catheter-based interventions.

Going forward, a larger and longer observational study will be needed to confirm the results, the authors write.

Study Details

At baseline, patients were taking the following medications:

• Bosentan (n = 14): 228 ± 47 mg
• Ambrisentan (n = 2): 7.5 ± 3.5 mg
• Sildenafil (n = 20): 55 ± 13 mg
• Tadalafil (n = 4): 30 ± 12 mg
• Oral beraprost (n = 5): 96 ± 33 µg
• Oral sustained release beraprost (n = 10): 312 ± 34 µg

Medications of 22 (78.6%) patients remained unchanged until the time of the last follow-up catheterization.