Table 1.
Patient Characteristics and Data at the Time of CPET
| Value | |
|---|---|
| Demographics | |
| Age, yr, mean ± SD | 50 ± 15 |
| Sex, F, n (%) | 35 (70) |
| BMI, kg m−1, mean ± SD | 26 ± 5 |
| Comorbidities, n (%) | |
| Asthma | 12 (24) |
| CAD | 4 (8) |
| COPD | 2 (4) |
| Diabetes mellitus | 2 (4) |
| Hypertension | 14 (28) |
| ILD | 2 (4) |
| Smoking status, n (%) | |
| Former | 10 (2) |
| Never | 40 (80) |
| Medications, n (%) | |
| ACE inhibitor/ARB | 8 (16) |
| BB | 5 (10) |
| CCB | 1 (2) |
| COVID-19 clinical characteristics | |
| Time from diagnosis to CPET, mean ± SD, mo | 6 ± 4 |
| Hospital admission, n (%) | 5 (10) |
| ICU admission, n (%) | 3 (6) |
| Mechanical ventilation, n (%) | 3 (6) |
| Post–COVID-19 symptoms, n (%) | |
| Two or more of the following | 6 (12) |
| Dyspnea on exertion | 28 (56) |
| Decreased endurance | 13 (26) |
| Chest pain | 3 (6) |
| Testing results | |
| CT chest, n (%) | 41 (82) |
| Time from CT chest to CPET, mean ± SD, mo | 1 ± 2 |
| Normal findings, n (%) | 14 (34) |
| Minimal GGO, n (%) | 10 (24) |
| Bronchial wall thickening, n (%) | 13 (32) |
| Peripheral reticulation, n (%) | 1 (2) |
| Pulmonary function test, n (%) | 50 (100) |
| Time from PFT to CPET, mean ± SD, mo | 1 ± 2 |
| FVC, L; FVC % predicted, mean ± SD | 3.8 ± 1; 96 ± 14 |
| FEV1, L; FEV1% predicted, mean ± SD | 3.1 ± 0.9; 98 ± 13 |
| FEV1/FVC, %, mean ± SD | 95 ± 12 |
| TLC, L; TLC % predicted, mean ± SD | 5.9 ± 1.3; 103 ± 13* |
| RVol, L; RVol % predicted, mean ± SD | 2.2 ± 0.6; 108 ± 21* |
| DlCOcor mL min-1 mm Hg; DlCOcor % predicted, mean ± SD | 26 ± 8; 109 ± 22† |
| Echocardiography at rest, n (%) | 39 (78) |
| Time from echocardiogram to CPET, mean ± SD, mo | 2 ± 3 |
| Normal LV ejection fraction, n (%) | 39 (100) |
| Grade 1 RV diastolic dysfunction, n (%) | 2 (5) |
| RV systolic dysfunction, n (%) | 8 (21) |
| RVSP, mean ± SD, mm Hg | 38 ± 3 |
| MPS at rest, n (%) | 8 (16) |
| Time from CPET to MPS, mean ± SD, d | 10 ± 90 |
| Normal, n (%) | 8 (100) |
| C-MRI at rest, n (%) | 9 (18) |
| Time from CPET to C-MRI, mean ± SD, mo | 1 ± 3 |
| CPET | |
| Reason for discontinuation of CPET, n (%) | |
| Dyspnea | 20 (40) |
| Overall fatigue | 15 (30) |
| Leg fatigue | 11 (22) |
| Lightheadedness | 2 (4) |
| Chest pain | 2 (4) |
| Dyspnea, Borg score, mean ± SD | 8 ± 1 |
| Leg fatigue, Borg score, mean ± SD | 8 ± 2 |
| WR max, Watts; % predicted, mean ± SD | 144 ± 49; 95 ± 22 |
| o2 max, L min−1; % predicted, mean ± SD | 1.6 ± 0.4; 95 ± 28 |
| o2 max/BW, ml kg min−1; % predicted, mean ± SD | 22.2 ± 6.0; 94 ± 29 |
| co2 max, L min−1; % predicted, mean ± SD | 2.0 ± 0.5; 95 ± 26 |
| RER, mean ± SD | 1.2 ± 0.1 |
| e max, L min−1, mean ± SD | 77 ± 19 |
| Vd/Vt, mean ± SD | 0.2 ± 0.1 |
| HR max, beats min−1, mean ± SD | 155 ± 22 |
| HRR, beats min−1, mean ± SD | 16 ± 14 |
| SpO2, % mean ± SD | 94 ± 4 |
| Lactate at peak, mmol L−1, mean ± SD | 10 ± 3‡ |
| Anaerobic threshold, %, mean ± SD | 51 ± 16 |
| Oxygen pulse, ml beat; % predicted, mean ± SD | 11 ± 3.8; 99 ± 33 |
| SBP; DBP, mm Hg, mean ± SD | 169 ± 25; 81 ± 13 |
Definition of abbreviations: ACE = angiotensin-converting enzyme; ARB = angiotensin receptor blocker; BB = β-adrenergic receptor antagonist; BMI = body mass index; CAD = coronary artery disease; COVID-19 = coronavirus disease; CCB = calcium channel blocker; C-MRI = cardiac magnetic resonance imaging; COPD = chronic obstructive pulmonary disease; CPET = cardiopulmonary exercise testing; CT = computed tomography; DBP = diastolic blood pressure; DlCOcor = DlCO corrected for altitude; GGO = ground glass opacifications; HR max = maximum heart rate; HRR = heart rate reserve; ILD = interstitial lung disease; LV = left ventricle; MPS = myocardial perfusion scan; PFT = pulmonary function test; RER = respiratory exchange ratio; RVol = residual volume; RV = right ventricle; RVSP = right ventricular systolic pressure; SBP = systolic blood pressure; SpO2 = oxygen saturation as measured by pulse oximetry; Vco2 max = exhaled maximum co2; o2 max = maximum o2; o2 max/BW = maximum Vo2 per kilogram body weight; WR max = maximum work rate.
N = 50.
n = 38.
n = 41.
n = 39.