An active fixation coronary sinus lead apparatus includes electrode support means which include an electrode support longitudinal axis. A plurality of electrode segments are supported by the electrode support means and are arrayed around the electrode support longitudinal axis. A plurality of insulation segments are supported by the electrode support means and are arrayed around the electrode support longitudinal axis at positions opposite to the electrode segments. In this respect, the insulation segments are interspersed between the electrode segments. Electrode segment orientation means are connected to the electrode support means for selectively orienting the electrode segments and the insulation segments around the electrode support longitudinal axis. Vessel anchoring means, which can include three flexible anchor wing portions, are connected to the electrode support means for anchoring the apparatus to an interior wall of a blood vessel. A pressure monitoring system can be connected to the vessel anchoring means for monitoring pressure inside the anchoring means.