MTHFR and Venous thrombosis: Targeted Boolean strategies were applied, combining terms such as “simultaneous arterial and venous thrombosis” OR “concurrent arterial and venous thrombosis”; “arterial thrombosis” AND “venous thrombosis” AND “massive pulmonary embolism”; and genetic keywords including “thrombophilia,” “thrombophilic polymorphisms,” “Factor V Leiden,” “MTHFR C677T,” “PAI-1 4G/5G,” and “ACE I/D.” Additional terms, such as “hyperhomocysteinemia,” “multiple genetic thrombophilia,” and “multiple genetic mutations and thrombosis,” were also explored.