Baseline characteristics of study population
| . | All patients with DVT (n = 1268) (%) . | Anatomical variants (n = 36) (%) . |
|---|---|---|
| Male | 784 (62) | 12 (33) |
| Female | 484 (38) | 24 (67) |
| Median age (IQR), y | 63 (47-76) | 37 (25-48) |
| . | All patients with DVT (n = 1268) (%) . | Anatomical variants (n = 36) (%) . |
|---|---|---|
| Male | 784 (62) | 12 (33) |
| Female | 484 (38) | 24 (67) |
| Median age (IQR), y | 63 (47-76) | 37 (25-48) |
| . | Nonanatomical variants (n = 1232) (%) . | Anatomical variants (n = 36) (%) . |
|---|---|---|
| Presenting symptoms | ||
| DVT symptoms: leg swelling/pain | 811 (66) | 31 (86) |
| PE symptoms: dyspnea/tachycardia | 98 (8) | |
| Screening | 231 (19) | |
| Scan results | 28 (2) | 4 (11) |
| Other | 64 (5) | 1 (3) |
| Provoking factors | ||
| Unprovoked | 289 (23) | 29 (81) |
| Provoked | 943 (77) | 7 (19) |
| Trauma | 289 (23) | |
| Lower limb fractures | 216 (18) | |
| Surgery (major) | 303 (25) | 1 (3) |
| Cellulitis/leg wounds | 73 (6) | |
| Immobility | 568 (46) | 5 (14) |
| Line-related | 120 (10) | |
| Malignancy | 208 (17) | |
| Risk factors | ||
| Risk factors present (exclude family history and previous VTE) | 218 (18) | 36 (100) |
| Inflammatory | 18 (1) | 1 (3) |
| COCP | 20 (2) | 7 (19) |
| Heparin-induced thrombocytopenia | 6 (0) | |
| Anatomical variants | ||
| MTS | 0 | 25 (69) |
| IVC variants | 0 | 11 (31) |
| Thrombophilia | 71 (6) | 2 (6) |
| Factor V Leiden mutation | 38 (3) | |
| Prothrombin gene mutation | 2 (0) | |
| Protein S deficiency | 3 (0) | |
| Protein C deficiency | 3 (0) | 1 |
| Antithrombin deficiency | 3 (0) | |
| Antiphospholipid syndrome | 17 (1) | 1 |
| Myeloproliferative neoplasm | 5 (0) | |
| Smoking | 55 (4) | 6 (17) |
| Obesity | 51 (4) | 3 (8) |
| Family history | 58 (5) | 4 (11) |
| Previous VTE | 225 (20) | 12 (33) |
| Dominant side of clot | ||
| Left | 497 (40) | 26 (72) |
| Right | 524 (43) | 4 (11) |
| Bilateral | 211 (17) | 6 (17) |
| Extent of DVT | ||
| Proximal | 1050 (85) | 34 (94) |
| Distal bilateral | 117 (9) | 0 |
| IVC involvement | 65 (5) | 2 (6) |
| Diagnosis | ||
| Initial imaging | ||
| Vascular Doppler ultrasound | 1177 (96) | 34 (94) |
| Angiography | 6 (0) | |
| CT | 33 (3) | 2 (6) |
| Other | 16 (2) | |
| Further imaging | ||
| Vascular Doppler ultrasound | 887 (72) | 4 (11) |
| Angiography | 14 (1) | 14 (39) |
| CT | 78 (6) | 16 (44) |
| Other | 9 (1) |
| . | Nonanatomical variants (n = 1232) (%) . | Anatomical variants (n = 36) (%) . |
|---|---|---|
| Presenting symptoms | ||
| DVT symptoms: leg swelling/pain | 811 (66) | 31 (86) |
| PE symptoms: dyspnea/tachycardia | 98 (8) | |
| Screening | 231 (19) | |
| Scan results | 28 (2) | 4 (11) |
| Other | 64 (5) | 1 (3) |
| Provoking factors | ||
| Unprovoked | 289 (23) | 29 (81) |
| Provoked | 943 (77) | 7 (19) |
| Trauma | 289 (23) | |
| Lower limb fractures | 216 (18) | |
| Surgery (major) | 303 (25) | 1 (3) |
| Cellulitis/leg wounds | 73 (6) | |
| Immobility | 568 (46) | 5 (14) |
| Line-related | 120 (10) | |
| Malignancy | 208 (17) | |
| Risk factors | ||
| Risk factors present (exclude family history and previous VTE) | 218 (18) | 36 (100) |
| Inflammatory | 18 (1) | 1 (3) |
| COCP | 20 (2) | 7 (19) |
| Heparin-induced thrombocytopenia | 6 (0) | |
| Anatomical variants | ||
| MTS | 0 | 25 (69) |
| IVC variants | 0 | 11 (31) |
| Thrombophilia | 71 (6) | 2 (6) |
| Factor V Leiden mutation | 38 (3) | |
| Prothrombin gene mutation | 2 (0) | |
| Protein S deficiency | 3 (0) | |
| Protein C deficiency | 3 (0) | 1 |
| Antithrombin deficiency | 3 (0) | |
| Antiphospholipid syndrome | 17 (1) | 1 |
| Myeloproliferative neoplasm | 5 (0) | |
| Smoking | 55 (4) | 6 (17) |
| Obesity | 51 (4) | 3 (8) |
| Family history | 58 (5) | 4 (11) |
| Previous VTE | 225 (20) | 12 (33) |
| Dominant side of clot | ||
| Left | 497 (40) | 26 (72) |
| Right | 524 (43) | 4 (11) |
| Bilateral | 211 (17) | 6 (17) |
| Extent of DVT | ||
| Proximal | 1050 (85) | 34 (94) |
| Distal bilateral | 117 (9) | 0 |
| IVC involvement | 65 (5) | 2 (6) |
| Diagnosis | ||
| Initial imaging | ||
| Vascular Doppler ultrasound | 1177 (96) | 34 (94) |
| Angiography | 6 (0) | |
| CT | 33 (3) | 2 (6) |
| Other | 16 (2) | |
| Further imaging | ||
| Vascular Doppler ultrasound | 887 (72) | 4 (11) |
| Angiography | 14 (1) | 14 (39) |
| CT | 78 (6) | 16 (44) |
| Other | 9 (1) |
COCP, combined oral contraceptive pill; IQR, interquartile range; PE, pulmonary embolism.