Tsuchiya A; Department of Cardiovascular Medicine, Hiroshima
Utsunomiya H; Kamigaichi A; Tsutani Y; Hamada A; Takeuchi M;
Hyodo Y; Mogami A; Takahari K; Ueda Y; Miyata Y; Okada M; Nakano Y

Circulation Journal. 90(4):376-387, 2026 Mar 25.

BACKGROUND: Decreased exercise tolerance after pulmonary resection for
lung cancer is strongly associated with a poor prognosis, but its
determinants remain underexplored. We investigated the mechanisms of
postoperative effort intolerance in lung cancer using combined
exercise-stress echocardiography and cardiopulmonary exercise testing
(ESE-CPET).

METHODS AND RESULTS: We prospectively analyzed 38 patients with suspected
non-small cell lung cancer who underwent pulmonary resection. Preoperative
and 6-month postoperative evaluations included resting echocardiography,
ESE-CPET, and pulmonary function tests. Pulmonary vascular function was
assessed using the mean pulmonary artery pressure/cardiac output (MPAP/CO)
slope (n=38). Postoperative peak oxygen consumption (VO2) significantly
decreased (19.4 vs. 17.3 mL/min/kg, P<0.001). Multiple regression analysis
identified left atrial reservoir strain (B 0.797 [95% confidence interval:
0.138-1.456], P=0.019) and number of resected segments (-5.448 [-10.99 to
-0.047], P=0.048) as independent predictors of postoperative change in
peak VO2. Subgroup analysis showed greater changes in systolic pulmonary
artery pressure during exercise (SPAP) and steeper postoperative MPAP/CO
slopes in patients with >=3 resected segments vs. <3 (P<0.001 and P=0.052
for time-group interaction). A preoperative MPAP/CO slope >2.0 predicted
larger increases in peak SPAP following >=3-segment resection (P=0.006),
signifying increased pulmonary vascular stress.

CONCLUSIONS: ESE-CPET demonstrated that extensive pulmonary resection
adversely affects postoperative exercise tolerance and pulmonary vascular
function, leading to greater SPAP and steeper MPAP/CO slopes.