Acute hypertensive response to +Gz acceleration in mildly hypertensive pilots

Two fighter pilots with mild hypertension and a mildly hypertensive response to exercise underwent ambulatory blood pressure monitoring during a routine flight that included a brief exposure to +4 Gz stress. They exhibited an acute elevation of both systolic and diastolic blood pressures during +4 Gz stress: from 140/90 and 135/90 mm Hg to 179/139 and 180/140 mm Hg, respectively. Heart rate reached 182 and 132 beats/min. These responses of hypertensives may reflect exaggerated baroreceptor and sympathetic responses which cause a pronounced over-shoot of blood pressure. The findings demonstrate the value of 24-h ambulatory blood pressure monitoring for documenting episodic elevations of blood pressure that do not influence the "normal" average blood pressure, but may nevertheless have important clinical implications.