No abstract

No abstract

Background. Atherosclerotic plaque fracture and dissection of the arterial wall are frequent concomitants of the balloon angioplasty process. The composition and morphology of plaque within the vessel may be critical in determining the extent of plaque fracture and dissection during balloon angioplasty. To

To evaluate the applicability of two-dimensional echocardiography to left ventricular volume determination, 30 consecutive patients undergoing biplane left ventricular cineangiography were studied with a wide-angle (84 degrees), phased-array, two-dimensional echocardiographic system. Two echographic projections were used to obtain paired, biplane, tomographic images of the left ventricle. We used the short-axis view (from the precordial window) as an anolog of the left anterior oblique angiogram, and the long-axis, two-chamber view (from the apex impulse window) as a right anterior oblique angiographic equivalent. A modified Simpson's rule formula was used to calculate systolic and diastolic left ventricular volumes from the biplane echogram and the biplane angiogram. These methods correlated well for ejection fraction (r = 0.87) and systolic volume (r = 0.90), but only modestly for diastolic volume (r = 0.80). These correlations are noteworthy because 65% of the patients had significant segmental wall motion abnormalities. The volumes determined from the minor-axis dimensions of M-mode echograms in 23 of the same patients correlated poorly with angiography.

Background-Enhanced external counterpulsation (EECP) is a noninvasive, pneumatic technique that provides beneficial effects for patients with chronic, symptomatic angina pectoris. However, the physiological effects of EECP have not been studied directly. We examined intracoronary and left ventricular hemodynamics in the cardiac catheterization laboratory during EECP. Methods and Results-Ten patients referred for diagnostic evaluation underwent left heart catheterization and coronary angiography from the radial artery. At baseline and then during EECP, central aortic pressure, intracoronary pressure, and intracoronary Doppler flow velocity were measured using a coronary catheter, a sensor-tipped high-fidelity pressure guidewire, and a Doppler flow guidewire, respectively. Similar to changes in aortic pressure, EECP resulted in a dramatic increase in diastolic (71Ϯ10 mm Hg at baseline to 137Ϯ21 mm Hg during EECP; ϩ93%; PϽ0.0001) and mean intracoronary pressures (88Ϯ9 to 102Ϯ16 mm Hg; ϩ16%; Pϭ0.006) with a decrease in systolic pressure (116Ϯ20 to 99Ϯ26 mm Hg; Ϫ15%; Pϭ0.002). The intracoronary Doppler measure of average peak velocity increased from 11Ϯ5 cm/s at baseline to 23Ϯ5 cm/s during EECP (ϩ109%; Pϭ0.001). The TIMI frame count, a quantitative angiographic measure of coronary flow, showed a 28% increase in coronary flow during EECP compared with baseline (Pϭ0.001). Conclusions-EECP unequivocally and significantly increases diastolic and mean pressures and reduces systolic pressure in the central aorta and the coronary artery. Coronary artery flow, determined by both Doppler and angiographic techniques, is increased during EECP. The combined effects of systolic unloading and increased coronary perfusion pressure provide evidence that EECP may serve as a potential mechanical assist device.

We conducted a randomized, controlled trial in 72 patients with heterozygous familial hypercholesterolemia to test whether reducing plasma low-density lipoprotein levels by diet and combined drug regimens can induce regression of coronary lesions. Four hundred fifty-seven lesions were measured before and after a 26-month interval by computer-based quantitative angiography. The primary outcome variable was within-patient mean change in percent area stenosis. Mean low-density lipoprotein cholesterol levels decreased from 7.32 +/- 1.5 to 4.45 +/- 1.6 mmol/L. The mean change in percent area stenosis among controls was +0.80, indicating progression, while the mean change for the treatment group was -1.53, indicating regression (P = .039 by two-tailed t test for the difference between groups). Regression among women, analyzed separately, was also significant. The change in percent area stenosis was correlated with low-density lipoprotein levels on trial. We conclude that reduction of low-density lipoprotein cholesterol levels can induce regression of atherosclerotic lesions of the coronary arteries in patients with familial hypercholesterolemia. The anticipation of benefit from treatment applies to women and men alike.

The retrograde and transseptal approaches are complementary; if one method fails, the other should be attempted, yielding an overall success rate close to 100%. Because patients undergo heparinization immediately after the arterial system is entered during a retrograde procedure, failure of that approach requires crossover to the transseptal method during a separate session or reversal of heparin; if the transseptal method is tried first, crossover to the retrograde approach can be accomplished easily during the same session. To avoid complications related to access, the transseptal method should be the first used in children, the elderly and those with arterial disease or hypertrophic ventricles.

Coronary ectasia is more prevalent in patients with FH than in other patients with coronary atherosclerosis and shows a strong inverse association with HDL cholesterol levels. This suggests that disordered lipoprotein metabolism in FH may predispose patients to aneurysmal coronary artery disease.