SUMMARY We have simplified the Gorlin formula and have compared our measurements of the aortic or mitral valve area, using the original Gorlin formula and the simplified valve formula in 100 consecutive patients. The valve area was measured by the simplified formula as cardiac output (I/min) divided by the square root of pressure differences across the valve.In patients with aortic stenosis of varying severity there was excellent correlation between the original One of the constants is the discharge coefficient that is an empirical constant with an assumed arbitrary value of 1 for the aortic valve and 0.7 for the mitral valve. The second constant is 44.5, which is equal to the square root of twice the gravity acceleration factor (980 cm/sec/sec). The flow across the valve is equal to the cardiac output (ml/min) divided by the product of the heart rate (beats/min) and the systolic ejection period or diastolic filling period (sec/beat). In 1972, Cohen and Gorlin revised the original formula and suggested the use of 0.85 for the mitral valve (instead of 0.7) as the discharge coefficient.2Because the original formula is cumbersome and time-consuming, it is rarely used by cardiologists who are not involved with hemodynamic measurements. We have simplified this formula, and our results by both the original and the simplified formulas in 100 patients with either aortic stenosis or mitral stenosis are the subject of this report. of the ejection to the dicrotic notch. The diastolic filling period was measured between the crossover points of the pulmonary artery wedge and the left ventricular pressure tracings. The heart rate was calculated at the time of cardiac output measurement by counting the RR cycles over a 60-second interval. The peak aortic gradient was measured as a simple peak-topeak gradient. The peaks were not necessarily at the exact time during systole. The mean pressure difference across the aortic or mitral valve was measured by planimetry. We used the same cardiac output in both the original Gorlin and the simplified formulas.The aortic or mitral valve area (cm2) was measured by the simplified formula as the cardiac output (1/min) divided by the square root of the pressure differences across the valve. For the aortic valve, we used either the peak or the mean pressure difference across the valve in the simplified formula, but for the mitral valve, we used only the mean pressure difference.We performed the statistical correlation by means of Pearson product moment correlation and the t test.

Five consecutive patients with proved left ventricular pseudoaneurysm (PA) and 22 patients with true aneurysm (TA) were studied by two-dimensional echocardiography (2DE). In four of the five patients with PA, 2DE successfully displayed the PA. The unique 2DE characteristics of PA include: (1) a sharp discontinuity of the endocardial image at the site of the PA communication with the left ventricular cavity; (2) a saccular or globular contour of the PA chamber; and (3) the presence of a relatively narrow orifice in comparison with the diameter of the PA fundus. In addition, 2DE detected the presence of thrombotic material within the extraventricular chamber in three of four cases. By deriving the ratios of the end-systolic orifice to diameter measurements for the patients with PA (0.37 +/- 0.07) compared with TA (1.00 +/- 0.08), we found that 2DE reliably differentiated PA from TA (p < 0.001). We conclude that 2DE is a useful noninvasive method for revealing left ventricular PAs and for distinguishing PA from TA. Considering the high risk of spontaneous rupture associated with pseudoaneurysms, this noninvasive capability is of paramount clinical importance.

Early atherosclerosis in LDL-receptor deficient rabbits, undetectable by angiography yet observed by intravascular ultrasound imaging and histology, is associated with marked changes in ex vivo residual strain. Alterations in vascular biomechanical properties, associated with changes in cholesterol content, may have physiologic consequences and may be useful in detecting and quantitating early atherosclerosis.