Kamigaichi A; Department of Surgical Oncology, Hiroshima University, Hiroshima, Japan.
Tsutani Y; Tsuchiya A; Utsunomiya H;Miyata Y; DMimae T; DeTsubokawa N; Nakano Y;Okada M;

JTO clinical and research reports [JTO Clin Res Rep] 2025 Sep 12; Vol. 6 (11), pp. 100903.
Date of Electronic Publication: 2025 Sep 12 (Print Publication: 2025).

Introduction: The rationale underlying the benefits of the parenchyma-preserving nature of sublobar resection (SR) compared with lobectomy remains unclear. This study aimed to assess postoperative changes in cardiopulmonary function after lobectomy and SR using exercise stress testing.
Methods: This prospective, observational study enrolled patients scheduled for lobectomy or SR. Changes in cardiopulmonary function at 6 months postoperatively were evaluated using exercise stress echocardiography and cardiopulmonary exercise tests.
Results: Initially, 41 patients were enrolled, with 20 patients in the lobectomy group and 18 patients in the SR group (16 segmentectomies, two wedge resections) after excluding three ineligible patients. Preoperatively, all patients demonstrated well-preserved cardiopulmonary function. The systolic pulmonary artery pressure (SPAP) change at peak exercise was significantly higher for lobectomy (median 26.5%; interquartile range [IQR] 0.6-60.1) than for SR (median -8.2%; IQR -38.7-11.7; p = 0.001), despite nonsignificant differences at rest ( p = 0.599). Postoperative exercise-induced pulmonary hypertension (exPH) occurred in nine patients (45%) in the lobectomy group but none in the SR group (0%, p = 0.010). Postoperative peak oxygen consumption during exercise decreased significantly in the lobectomy group (median -14.3%; IQR -24.0 to -4.2) compared with that in the SR group (median -7.8%; IQR -13.5-8.7; p = 0.024). The postoperative increase in SPAP at peak exercise (r = 0.402, p = 0.012), prevalence of postoperative exPH (r = 0.978, p = 0.004), and postoperative decrease in peak oxygen consumption (r = -0.330; p = 0.041) were correlated with the number of resected segments.
Conclusions: Lobectomy induces increased SPAP during exercise, exPH, and effort intolerance, compared with SR. This highlights the importance of preserving lung parenchyma in lung surgery.
Clinical Trial Registration: This trial is registered in the UMIN Clinical Trials Registry under the code UMIN000053694.