# Impact of disease location and laterality on hemodynamic response following pulmonary thromboendarterectomy for chronic thromboembolic pulmonary hypertension

## TL;DR

This study examines how the location and side of lung disease affects heart and lung function improvement after surgery for a type of high blood pressure.

## Contribution

The study is the first to investigate how disease location and lung laterality affect hemodynamic outcomes after pulmonary thromboendarterectomy.

## Key findings

- Disease in the right lower and middle lobes and left lower lobe correlates with hemodynamic improvement.
- Overall disease burden shows only modest correlation with pulmonary vascular resistance reduction.

## Abstract

In patients with chronic thromboembolic pulmonary hypertension (CTEPH) undergoing pulmonary thromboendarterectomy (PTE), obstructive disease burden predicts positive hemodynamic responsiveness. However, the effect of disease location (upper, middle, or lower lobes) and lung laterality (right or left) has not been studied.

Examine the effect of obstructive disease location and laterality on hemodynamic response following PTE.

This analysis is a retrospective cohort study of 56 consecutive patients diagnosed with CTEPH who underwent PTE at the University of Michigan Hospital between August 2019 and July 2022. Disease burden, location, and laterality were assessed on invasive pulmonary angiography (IPA), and lobar segments were assigned a score based on these features and correlated with an absolute change in pulmonary vascular resistance (PVR) following PTE. The relationship between disease burden and hemodynamic responsiveness was modeled using linear regressions with R2 reported as a measure of correlation.

Most patients were World Health Organization (WHO) class III or IV (n = 47; 83.9%) and had a history of acute pulmonary embolism (n = 51; 91.1%). A modest correlation between patients’ overall disease burden and absolute change in PVR was noted, with the strongest contributions from the right lower lobe (RLL), right middle lobe (RML), and left lower lobe (LLL) (R2 = 0.16, 0.10, and 0.03, respectively).

Disease location in the RLL, RML, and LLL may predict hemodynamic improvement in patients with CTEPH undergoing PTE.