CardioMassTTE-1151: A Multicenter Transthoracic Echocardiography Dataset for Intracardiac Mass Segmentation and Thrombus Classification

CardioMassTTE-1151 is a multicenter transthoracic echocardiography dataset for intracardiac mass segmentation and thrombus/non-thrombus classification. The dataset contains 1,151 de-identified TTE key-frame images and 1,151 paired lesion segmentation masks from patients with intracardiac masses. The dataset is divided into a training cohort (727 cases), internal testing cohort (172 cases), temporal validation cohort (185 cases), and external validation cohort (67 cases). Thrombus cases account for 448, 98, 96, and 22 cases in these cohorts, respectively; non-thrombotic masses account for 279, 74, 89, and 45 cases, respectively. The released package includes paired image and mask folders, case-level metadata, cohort split information, a data dictionary, README file, and SHA256 checksums for file integrity verification.