diff --git a/new_pipeline/stage_2_make_heartbeat_mask.py b/new_pipeline/stage_2_make_heartbeat_mask.py
index be19083..ee7a8f9 100644
--- a/new_pipeline/stage_2_make_heartbeat_mask.py
+++ b/new_pipeline/stage_2_make_heartbeat_mask.py
@@ -20,17 +20,24 @@ mylogger.info("loading config file")
 with open("config.json", "r") as file:
     config = json.loads(jsmin(file.read()))
 
-threshold: float = 0.05
+
 path: str = config["ref_image_path"]
 use_channel: str = "donor"
 spatial_width: float = 4.0
 temporal_width: float = 0.1
 
+threshold: float = 0.05
+
+heartbeat_mask_threshold_file: str = os.path.join(path, "heartbeat_mask_threshold.npy")
+if os.path.isfile(heartbeat_mask_threshold_file):
+    mylogger.info(f"loading previous threshold file: {heartbeat_mask_threshold_file}")
+    threshold = float(np.load(heartbeat_mask_threshold_file)[0])
+
+mylogger.info(f"initial threshold is {threshold}")
 
 image_ref_file: str = os.path.join(path, use_channel + ".npy")
 image_var_file: str = os.path.join(path, use_channel + "_var.npy")
 heartbeat_mask_file: str = os.path.join(path, "heartbeat_mask.npy")
-heartbeat_mask_threshold_file: str = os.path.join(path, "heartbeat_mask_threshold.npy")
 
 device = get_torch_device(mylogger, config["force_to_cpu"])
 
@@ -124,7 +131,7 @@ mylogger.info("Add controls")
 axfreq = fig.add_axes(rect=(0.4, 0.9, 0.3, 0.03))
 slice_slider = Slider(
     ax=axfreq,
-    label="Slice",
+    label="Threshold",
     valmin=0,
     valmax=value_sort_max,
     valinit=threshold,