Substantial recurrence risk after venous thromboembolism provoked by minor risk factors

Impact of Perioperative Thromboembolic Complications on Future Long-term Risk of Venous Thromboembolism among Medicare Beneficiaries Undergoing Complex Gastrointestinal Surgery

BACKGROUND

Venous thromboembolism (VTE), including deep venous thrombosis (DVT) and pulmonary embolism (PE), represents a common cause of morbidity and mortality following complex gastrointestinal surgery. Whether perioperative VTE also exposes patients to a higher long-term risk of VTE events remains poorly defined.

METHODS

The Medicare 100% Standard Analytic Files were used to identify patients undergoing esophageal, hepatic, pancreatic, and colorectal resection between 2013 and 2017. The impact of perioperative VTE, defined as a VTE episode occurring during the index hospitalization or within 30 days of discharge, on the risk of developing subsequent long-term VTE episodes (i.e., more than 30 days following discharge) was examined.

RESULTS

Among 253,212 patients who underwent complex gastrointestinal surgery, 1.9% (n=4763) developed a VTE episode perioperatively. With a median follow-up period of 553 days (IQR 194-1052), a total of 11,052 patients (4.4%) developed a long-term VTE episode. Of note, patients who developed a DVT perioperatively had a higher risk of experiencing a long-term VTE episode than patients who had no perioperative thromboembolic complications (HR 6.50, 95%CI 6.04-6.98). The increase in risk was more pronounced among patients who had a PE (HR 27.97, 95%CI 25.39-30.80) at the time of surgery. Risk factors for long-term thromboembolic events following complex GI surgery included Black patients (HR 1.20, 95%CI 1.11-1.30), receipt of surgery at a teaching hospital (HR 1.09, 95%CI 1.04-1.13), nonelective surgery (HR 1.19, 95%CI 1.14-1.24), as well as a diagnosis of cancer (HR 1.10, 95%CI 1.05-1.16). The development of a perioperative DVT was associated with an increased long-term risk of VTE in both cancer (HR 5.59, 95%CI 5.29-6.61) and non-cancer patients (HR 6.98, 95%CI 6.37-7.64). Similarly, experiencing a PE at the time of surgery led to a higher long-term risk of VTE in cancer (HR 24.30, 95%CI 21.08-28.02), as well as non-cancer (HR 30.81, 95%CI 27.01-35.15) patients.

CONCLUSIONS

Patients with a history of perioperative VTE had a higher risk of developing subsequent VTE events within 1-2 years following complex GI surgery. The risk was more pronounced among patients who had perioperative PE rather than DVT. These findings were consistent among both cancer and non-cancer patients.

An international survey of clinicians regarding their management of venous thromboembolism following the initial 3-6 months of anticoagulation

After an initial treatment period for venous thromboembolism (VTE), indefinite anticoagulation may be considered, depending upon individual risks. The aim of the study was to determine if there is consensus amongst clinicians that manage VTE regarding which patients require 3-6 months versus indefinite anticoagulation. The importance of VTE site and severity in decision making was also evaluated. An international survey of clinicians involved in VTE management was undertaken. Respondents were asked about long-term treatment of six patients that had completed 3-6 months initial anticoagulation. These included four cases of VTE not associated with a major reversible risk factor and two control cases; one unprovoked VTE and one VTE associated with a major reversible risk factor. For consensus, there was a pre-defined equivalence boundary whereby at least 70% of clinicians had to decide either to stop or consider indefinite anticoagulation for each case. 351 responses were collected. In the control cases, there was a ≥ 95% consensus on long-term management (stop versus indefinite anticoagulation). In three of the four test cases, there was no consensus about duration of anticoagulation. In case 3, 78% (99% confidence interval 73-84%) would stop anticoagulation after 3-6 months. When analysed by grade or specialty of doctor, a lack of consensus remained. Opinion on whether site or severity of VTE influenced decision making was variable. For patients with unprovoked VTE or VTE associated with a major transient risk factor there is treatment consensus. For the remainder, there is a lack consensus regarding the need for indefinite anticoagulation.

D-dimer levels and risk of recurrence following provoked venous thromboembolism: findings from the RIETE registry

BACKGROUND

Patients with venous thromboembolism (VTE) secondary to transient risk factors may develop VTE recurrences after discontinuing anticoagulation. Identifying at-risk patients could help to guide the duration of therapy.

METHODS

We used the RIETE database to assess the prognostic value of d-dimer testing after discontinuing anticoagulation to identify patients at increased risk for recurrences. Transient risk factors were classified as major (postoperative) or minor (pregnancy, oestrogen use, immobilization or recent travel).

RESULTS

In December 2018, 1655 VTE patients with transient risk factors (major 460, minor 1195) underwent d-dimer measurements after discontinuing anticoagulation. Amongst patients with major risk factors, the recurrence rate was 5.74 (95% CI: 3.19-9.57) events per 100 patient-years in those with raised d-dimer levels and 2.68 (95% CI: 1.45-4.56) in those with normal levels. Amongst patients with minor risk factors, the rates were 7.79 (95% CI: 5.71-10.4) and 3.34 (95% CI: 2.39-4.53), respectively. Patients with major risk factors and raised d-dimer levels (n = 171) had a nonsignificantly higher rate of recurrences (hazard ratio [HR]: 2.14; 95% CI: 0.96-4.79) than those with normal levels. Patients with minor risk factors and raised d-dimer levels (n = 382) had a higher rate of recurrences (HR: 2.34; 95% CI: 1.51-3.63) than those with normal levels. On multivariate analysis, raised d-dimers (HR: 1.74; 95% CI: 1.09-2.77) were associated with an increased risk for recurrences in patients with minor risk factors, not in those with major risk factors.

CONCLUSIONS

Patients with raised d-dimer levels after discontinuing anticoagulant therapy for VTE provoked by a minor transient risk factor were at an increased risk for recurrences.

[Modern treatment of deep vein thrombosis and pulmonary embolism]

Virchow's triad has been known for a 100 years. The development of therapeutic possibilities during this time was enormous. Today anticoagulant therapy is much more differentiated. Four new oral substances have replaced the traditional treatment with vitamin K antagonists in angiology. A standardized dosage is available. The monitoring of the coagulation parameters is no longer necessary, but it is important to monitor renal function. Direct oral anticoagulants are approved for the treatment of venous thrombosis and pulmonary embolism, but not during pregnancy or in children. Severe bleeding complications, especially intracerebral bleeding, are less common. The incidence of venous thromboembolism is still high. Obesity and cancer are of particular importance. The "therapeutic pact" with the patient requires that physicians master the art of "talking medicine".