Measuring Transmitral Gradient With Single Radial Access Using a Dual-Lumen Catheter

To measure the transmitral gradient (TMG) with a dual-lumen pigtail catheter with single radial-arterial access to obtain simultaneous left atrial (LA)/left ventricular (LV) pressures.

Key steps include the following: 1) with radial arterial access, use a 5-F TIG 4.0 diagnostic catheter, and advance a 0.035-inch J-wire across the aortic valve in a retrograde fashion; 2) advance catheter into LV; 3) advance floppy 0.035-inch Tru-Torque wire beyond the mitral valve into the LA and pulmonary vein; 4) advance TIG catheter over the wire into the LA; 5) exchange TIG catheter for a Langston dual-lumen catheter; 6) place distal pigtail portion into the LA and proximal pressure port in the LV, obtain concurrent LA/LV pressures, and calculate TMG and MVA with Gorlin equation.

In patients with atrial fibrillation, advancing the catheter across the mitral valve presents risk of dislodging a preexisting thrombus from the left atrial appendage.

This method offers a simple and efficient approach to a direct TMG assessment.