Which conditions are considered high VTE risk?

The condition characterized by a mitral mechanical valve combined with a prior venous thromboembolism (VTE) event is recognized as a high risk for VTE. This situation is significant because mechanical heart valves can disrupt normal blood flow and promote thrombus formation, especially in the presence of other risk factors such as a history of VTE. The previous VTE event serves as a strong indicator of underlying susceptibility to thrombosis, suggesting that the patient may have an ongoing vulnerability to clot formation.

In contrast, atrial fibrillation, while it can be a risk factor for stroke due to thrombus formation in the heart, does not inherently suggest a past VTE event or lasting anatomical changes that lead to venous stasis, particularly in the absence of mechanical valves. Heart failure without structural defects and hypertension alone do not indicate a high risk for VTE, as they may complicate the clinical picture but do not directly contribute to the development of thrombi in the same way the combination of a mechanical valve and a history of VTE does.