ABSTRACT
A 40-year-old man was found to have hypertrophic cardiomyopathy (HCM) with severe mid ventricular obstruction. The obstruction produced two distinct left ventricular chambers with an estimated 60 mmHg continuous wave (CW) Doppler intraventricular gradient. Pulsed wave (PW) Doppler showed high velocity systodiastolic flow from apex to base and flow from base to apex confined mostly to the second half of diastole. Cardiac magnetic resonance (CMR) showed midventricular obstruction, due to septal, parietal, and to an hypertrophic, double posteromedial papillary muscle; an apical aneurysm was detected. Aneurysm is underdiagnosed by echocardiography in HCM and an accurate anatomic definition is needed if surgery is planned; thus, a CMR should always be obtained in these patients.
ABSTRACT
BACKGROUND: To measure renal blood flow (RBF) from the renal veins in men using the intravascular Doppler technique (IVD). METHODS: In nine hypertensive male patients (age 46-64 years) undergoing diagnostic renal artery angiography and renal vein catheterization to determine plasma renin activity (PRA), a 3F Doppler catheter was positioned in the renal veins using a 7F guide catheter with a "basket" shaped tip. The radiopaque sectors of the catheter, leaning against the vessel wall, serve to measure the internal diameter of renal veins, and therefore to calculate RBF, by multiplying renal vein cross-sectional area by mean blood flow velocity. The resulting RBF from the left and right renal veins were compared with those obtained by the local thermodilution method (TD). RESULTS: We found good agreement (Bland and Altman's method) between the RBF measurements made with IVD (ranging from 46 mL/min to 1,220 mL/min) and with the TD technique (45-1,030 mL/min) (mean bias, 13+/-20 mL/min, 95% CI -54.77 to 28.77 mL/min). In stenotic kidneys a significant correlation was found between the renal vein PRA and RBF calculated with both methods (IVD: r = 0.96, p = 0.002; TD: r = 0.90, p = 0.01). CONCLUSIONS: The IVD technique applied to the venous side of the renal circulation provides a simple and reliable method for separate measurement of RBF in kidneys with and without renal artery stenosis.
