MKI67 and heart failure: During 9.6 ± 7.2-year (median 8[4–13]) follow-up, 7% developed a new PPGL, 5% a PPGL-metastasis (KI67 > 2% n = 2; KI67 ≤ 1% n = 3; tumor size ≥ 95 mm n = 4), and 13% died (metastatic pheochromocytoma n = 2, hypertensive crisis n = 1, heart failure n = 2, other malignancies n = 5, and unclear n = 4).