Correlation of an invasive measure of right ventricular pressure and mean arterial pressure.

Recently, cardiac pacemakers have been introduced which increase heart rate during exercise. Current rate responsive pacemakers achieve this objective by monitoring minute ventilation via a transvenous impedance measurement and provides a proportional heart rate increase with increases in minute ventilation. These devices are independent of hemodynamic parameters. Therefore, the potential exists for a sufficiently high rate which results in decreased cardiac output by virtue of Starling's Principle. An invasive measure of right ventricular (RV) pressure is compatible with the power and complexity of contemporary implantable pacemakers. In addition, mean arterial pressure is accepted as a diagnostic indicator of left ventricular hemodynamic compromise. Therefore, a correlation of right ventricular pressure and mean arterial pressure was undertaken. Twenty-six patients were studied during normal sinus rhythm and ventricular tachycardia during routine electrophysiology examination. A beat to beat measure of peak to peak RV pressure resulted in a correlation coefficient of 0.68 with mean arterial pressure.