Echocardiographic and functional cardiopulmonary problems 6 months after first-time pulmonary embolism in previously healthy patients

Abstract

We hypothesized that first-time submassive pulmonary embolism (PE) can cause persistent, significant cardiopulmonary problems, including right ventricular damage and worsened quality of life in patients with no prior cardiopulmonary disease. We prospectively enrolled 205 patients without end-stage comorbidity diagnosed with submassive PE (systolic blood pressure always > 100 mmHg). Using explicit criteria, we identified a subgroup of 127 ‘previously healthy’ patients who were free of cardiopulmonary disease or other disabling process. All patients had transthoracic echocardiography (echo) at the time of diagnosis. Six months later, survivors returned for repeat echo, 6 min walk distance (6MWD), and a quality-of-life survey. We defined a significant cardiopulmonary problem as either: (i) abnormal RV on echo (RV dilation or RV hypokinesis); or (ii) NYHA score > II or a 6MWD < 330 m at 6 months. Of 127 study patients, five had inadequate echos, nine were lost to follow-up, and four died, leaving 109 with complete data. Of 109 patients, 45 (41%) had cardiopulmonary problems 6 months after PE: 18 of 109 (17%) had only an abnormal RV, 18 of 109 (17%) had only functional limitation, and nine of 109 (8%) had both. Twenty-two patients (20%) indicated at least one index of poor quality-of-life: health status worse, not currently shopping, or perceived need for oxygen at home. Patients with cardiopulmonary problems demonstrated a significant decrease in SaO₂% after 6MWD (97 ± 1.3 pre-6MWD vs. 96 ± 1.8% post-6MWD, P = 0.004 by paired t-test). Six months after first-time PE, 41% of previously healthy patients had either an abnormal RV on echo, an NYHA score > II or a 6MWD < 330 m. Treatment studies of PE should include these persistent cardiopulmonary problems as study endpoints.